Embodiments are directed to using an anomalous hall effect (AHE) or a polarized spin hall effect (PSHE) to switch a magnetic moment of a free layer having perpendicular magnetic anisotropy (PMA). AHE/PSHE includes materials with spontaneous magnetic moment. Thus, the spin orientation generated by AHE/PSHE not only depends upon the geometrical orientation, but also on the magnetic moment orientation of the AHE/PSHE material. Therefore, out-of-plane polarized spins are injected into the magnetic free layer, and the corresponding spin current switches the magnetic moment of a magnetic free layer with PMA through the anti-damping mechanism. In some embodiments, an asymmetric bottom lead may be used, such that a tunneling current flows toward one side after it leaves the free layer.

The present disclosure relates generally to electronic memory technology, and more specifically to generating spin current for spin transfer torque magnetic random access memory (STT-MRAM) using an anomalous hall effect and/or polarized spin hall effect.
Electronic memory may be classified as either volatile or non-volatile. Volatile memory requires constant power to retain stored data, while non-volatile memory does not. A common memory found in computers is volatile random access memory (RAM), which provides fast read/write speeds and easy re-write capability. However, when system power is switched off, any information not copied from volatile RAM to a hard drive is lost. Although non-volatile memory does not require constant power to retain its stored data, it in general has lower read/write speeds and a relatively limited lifetime in comparison to volatile memory.
Magnetoresistive random access memory (MRAM) is a non-volatile memory that combines a magnetic device with standard silicon-based microelectronics to obtain the combined attributes of non-volatility, high-speed read/write operations, high read/write endurance and data retention. Data is stored in MRAM as magnetic states or characteristics (e.g., polarity or magnetic moment) instead of electric charges. In a typical configuration, each MRAM cell includes a transistor, a magnetic tunnel junction (MTJ) device for data storage, a bit line and a word line. In general, the MTJ's electrical resistance will be high or low based on the relative magnetic states of certain MTJ layers. Data is written to the MTJ by applying certain magnetic fields or charge currents to switch the magnetic states of the MTJ layers. Data is read by detecting the resistance of the MTJ. Using a magnetic state/characteristic for storage has two main benefits. First, unlike electric charge, magnetic state does not leak away with time, so the stored data remains even when system power is turned off. Second, switching magnetic states has no known wear-out mechanism.
The term "magnetoresistance" describes the effect whereby a change to certain magnetic states of the MTJ storage element results in a change to the MTJ resistance, hence the name "Magnetoresistive" RAM. A typical MTJ includes a fixed magnetic layer, a thin dielectric tunnel barrier and a free magnetic layer. The MTJ has a low resistance when the magnetic moment of its free layer is parallel to the magnetic moment of its fixed layer. Conversely, the MTJ has a high resistance when its free layer magnetic moment is oriented anti-parallel to its fixed layer magnetic moment. The MTJ can be read by activating its associated word line transistor, which switches current from a bit line through the MTJ. The MTJ resistance can be determined from the sensed current, which is itself based on the polarity of the free layer. Conventionally, if the fixed layer and free layer have the same polarity, the resistance is low and a "0" is read. If the fixed layer and free layer have opposite polarity, the resistance is higher and a "1" is read.
Spin Transfer Torque MRAM (STT-MRAM) uses electrons that have been spin-polarized to switch the magnetic state of the MTJ free layer. During the write operation, the spin-polarized electrons exert a torque on the free layer, which can switch the free layer magnetic state. Thus, the required amount of STT-MRAM writing current depends on how efficiently spin polarization is generated. Additionally, designs that keep write currents small (e.g., Ic<25 micro-ampere) are important to improving STT-MRAM scalability. This is because a larger switching current would require a larger transistor area, which would inhibit the ability to scale up STT-MRAM density.
A typical STT-MRAM configuration uses a thin film (e.g., spin filter) to spin polarize electrons as they pass through the film. The Spin Hall Effect (SHE) has been proposed as an alternative approach to generating spin polarized electrons and their resultant spin current. For example, a non-magnetic SHE material could, in theory, be used to generate spin current in the transverse direction while a charge current flows longitudinally. The generated spin current can be injected into an adjacent layer to switch the adjacent layer's magnetic state. For each electron that passes through the SHE material there can be more than one spin injected into the adjacent layer, which can result in a high rate of efficiency in transferring the spin angular momentum.
However, it can be difficult to combine SHE material with an MTJ. For example, as described above, the tunneling current through the MTJ and the current that provides the SHE flow in different paths and in different directions (e.g., orthogonal to one another). In conventional designs, three terminal devices are used wherein the tunneling current across the MTJ and the current that generates the SHE torque are applied across different pairs of terminals. These and other issues are addressed by a pending U.S. patent application, assigned to the assignee of the present disclosure and filed Mar. 15, 2013, entitled "SPIN HALL EFFECT ASSISTED SPIN TRANSFER TORQUE MAGNETIC RANDOM ACCESS MEMORY," by John K. DeBrosse, Luqiao Liu and Daniel Worledge, having U.S. application Ser. No. 13/835,355, and expressly incorporated by reference herein.
Other designs that attempt to use SHE material to switch a free layer magnetic state generally deal with MTJs having in-plane magnetic anisotropy, which means that the activation energy cannot be very high for small junctions (e.g., L. Liu et al., "Spin-Torque Switching with the Giant Spin Hall Effect of Tantalum," Science, Volume 336, No. 6081, 4 May 2012, pp. 555-558). Although designs have been proposed for using SHE material to switch a free layer magnetic state having perpendicular magnetic anisotropy (PMA), these designs suffer from significant inefficiencies (e.g., I. M. Miron, K. Garello, G. Gaudin, P.-J. Zermatten, M. V. Costache, S. Auffret, S. Bandiera, B. Rodmacq, A. Schuhl and P. Gambardella, Nature (London) 476, 189 (2011); and Luqiao Liu, O. J. Lee, T. J. Gudmundsen, D. C. Ralph and R. A. Buhrman, Phys. Rev. Lett. 109, 096602 (2012)).
Accordingly, there still is a need for non-volatile memory that efficiently lowers the switching current for STT-MRAM configurations having PMA.

Utilization of the anomalous hall effect or polarized spin hall effect for MRAM applications

International Business Machines Corporation


An input current (Iin) is transformed into an output integrated voltage (Vout_int) using a parallel connection of an operational transconductance amplifier and an integration capacitor. The output integrated voltage is reduced by repeatedly discharging the integration capacitor through a feedback loop via a digital-to-analog converter generating feedback pulses, a feedback clock period (Tclk_DAC) defining time intervals between successive rising edges of the feedback pulses. Sampling is performed during an extended feedback clock period (T*) after a lapse of a plurality of feedback clock periods (Tclk_DAC).

An integration circuit is a circuit block often employed in delta-sigma analog-to-digital converters. Delta-sigma modulation converts an analog voltage into a pulse frequency. A particular type of Delta-Sigma converter consists of two conversion stages, where after a coarse voltage conversion, the residual voltage is sampled and converted to a digital signal by the second converter stage.
A general schematic of a current integration configuration is depicted in FIG. 6a. FIG. 6b is a corresponding timing diagram, which shows the temporal variation of the relevant signals and quantities on a time line pointing towards the right. The signal indicated as "clk" is the clock signal providing the minimum time unit employed in the circuit. The signal indicated as "sample" is high only during the sampling time, which in this example equals the clock period. The signal indicated as "clkDAC" is derived from "clk" and is the clock signal provided for the feedback DAC to produce a synchronized feedback voltage "Vout_fb" based on the previous comparator decision. "Iin" is the input current, which is assumed to be constant in the example of FIG. 6b. "Vout_int" is the output integrated voltage, which is indicated in FIG. 6a.
The input current Iin is integrated on the integration capacitor Cint, thus leading to a growing output integrated voltage Vout_int:
      V          out            _            in            t        =            -              1                  C          int                      ·                  ∫        0        t                                    I          in                ·        dt
The output integrated voltage Vout_int will eventually saturate and is kept in the allowed range by means of a feedback loop. Pulsed feedback is effected by a digital-to-analog converter (DAC), which may be a switched capacitor digital-to-analog converter or a switched current source digital-to-analog converter. The DAC removes charge packages from the integration capacitor Cint during the feedback clock period Tclk_DAC when the previous comparator decision was logic zero to keep |Vout_int|<Imax·Tckl_DAC for a maximal input current Imax. Owing to the pulsed nature of the feedback clock signal clkDAC, settling is required within one feedback clock period Tclk_DAC. This impacts the output noise and increases the power consumption significantly.
The total output noise Vnoise_out,rms is calculated as follows. The input referred noise of the operational transconductance amplifier (OTA) is applied at the positive input in the voltage domain (Vin+ in FIG. 6a). Thus it is not integrated, but amplified by the inverse feedback factor β−1=1+(Cp/Cint):
      V          noise            _            out        =                    1        β            ·              V                  noise                    _                    in                      =                  (                  1          +                                    C              p                                      C              int                                      )            ·              V                  noise                    _                    in
In order to obtain the total output noise after sampling, Vnoise_out must be integrated over the whole spectrum:
      V                  noise                _                ou                t            ,      rms        =                    ∫        0        ∞                                                (                                          1                β                            ·                                                V                                      noise                                        _                                        in                                                                                (                  f                  )                                            ·                              1                                  1                  +                                      2                                                              π                      ·                      f                                                                                /                                                            BW                                                                        )                    2                ·        df
Assuming constant white noise Vin=kn/gm with transconductance gm and noise constant kn, this yields:
      V                  noise                _                ou                t            ,      rms        =                              1                      β            2                          ·                              k            n                                g            m                          ·                  π          2                ·                  BW                      2                        π                                =                            1                      β            2                          ·                              k            n                                g            m                          ·                  BW          4
Inserting
      BW    =                  GBW                  A          DC                    =                                    g            m                                C            eq                          ·        β              ,where GBW is the gain-bandwidth product and Ceq=Cs+(Cint∥Cp), yields
                              V                                    noise                            _                            ou                            t                        ,            rms                          =                                                                              k                  n                                                  g                  m                                            ·                                                g                  m                                                  4                  ·                                      C                    eq                                                              ·                              1                β                                              =                                                                      k                  n                                                  4                  ·                                      C                    eq                                                              ·                              1                β                                                                        (        1        )
Consequently, the output noise is independent of the transconductance gm and therefore independent of the power consumption. The reason is that a smaller transconductance gm increases noise, but at the same time reduces the gain-bandwidth product GBW, resulting in higher noise filtering. The calculation so far assumed that the GBW value is not relevant, i. e. the power consumption can be arbitrarily reduced at the cost of settling speed. However, typically there is a settling requirement related to feedback clock period Tclk_DAC:
                    settling_factor        =                                            T                              clk                                _                                DAC                                                    τ              ota                                =                                                    T                                  clk                                    _                                    DAC                                                            1                BW                                      =                                                            T                                      clk                                        _                                        DAC                                                                    C                  eq                                            ·                              g                m                            ·              β                                                          (        2        )
Solving equation (2) for Ceq and substituting the expression thus obtained in equation (1) yields
      V                  noise                _                ou                t            ,      rms        =                              k          n                          4          ·                      T                          clk                            _                            DAC                                ·                      g            m                    ·                      β            2                              ·      settling_factor
The settling time is tied to the DAC clock period due to the pulsed nature of the feedback DAC. Using a non-pulsed continuous feedback current would alleviate the settling constraint. However, this does not provide the inherent analog-to-digital conversion present in the DAC based feedback.
Alternatively, a smoothing filter could be used after the DAC, but this can cause instability in a higher order feedback path. Furthermore, the feedback current does not have a one to one correspondence to the DAC pulses, because it is not known how much of the current comes from the feedback pulses directly before and after output sampling.

Method and circuit for current integration


By using a LAN emulation in an ATM environment, end systems such as workstations etc. can connect to the ATM network while software applications interact as if they are attached to a traditional LAN. The invention is a simple technique for emulating a LAN on an ATM network. According to the invention, each end system is identified by hub and port identifiers which represent a hub and a port of the hub to which the end system is connected. By labelling each ATM cell, and proper label translation at hubs, a LAN can be emulated without using network servers which would introduce cumbersome extra procedures.

A LAN is a digital communications network interconnecting several local computer workstations through a shared medium. It is also possible to connect two or more LANs. The communication network interconnecting remote LANs is referred to generally as a WAN (wide area network). In one form, a WAN is a network containing some switching mechanism to which each LAN is connected by a bridge. In another form, a WAN is a simple point-to-point link for interconnection of only two remote LANs.
U.S. Pat. No. 4,901,312, issued Feb. 13, 1990 to Hui et al describes remote interconnection of LANs by a virtual or pseudo ring formed in a WAN by e.g., a packet switching network.
U.S. Pat. No. 5,329,527, issued Jul. 12, 1994 to Ujihashi et al describes a system in which two or more LANs are interconnected by way of an ATM network by respective bridges to effect communication between terminals. In the system of the patent, each bridge has an address table for local terminals and a second table containing logical connection identifiers to other bridges and addresses of remote terminals connected to other bridges.
An ATM service called "LAN emulation" that emulates services of existing LANs across an ATM network allows the use of the vast base of existing LAN application software. By using such a service, end systems (e.g. workstations, servers, bridges, etc.) can connect to the ATM network while the software applications interact as if they are attached to a traditional LAN.
There are several advantages that a LAN emulation based on ATM (or other switching technologies) has over a true shared medium LAN. A LAN emulation:
breaks geographical limitations on the separation of stations participating on the same LAN segment, in particular when a station is moved to a new location within the same enterprise it could remain in the same LAN segment; PA1 can accommodate many more stations on the same LAN segment; and PA1 can be partitioned into LAN segments based upon functional requirements, not geographical proximity.
The ATM Forum is defining a technology of emulating shared media LAN segments on ATM networks. It regards the LAN emulation as important for both accommodating existing LAN-based protocols on ATM stations and for providing connectivity between ATM stations and stations on "legacy" LANs. The architecture underpinning the ATM Forum's effort is based upon servers. For example, a server provides address resolution, i.e. obtaining the ATM address representing the station with a particular address, and a multicast server handles multicast traffic. A station can also open a point-to-point VCC (virtual channel connection) to another station once it has found its ATM address. Besides a direct data transfer through a VCC, the source can also make use of a data forwarder server. A server station sends packets to the data forwarder server when it does not know the destination's ATM address. The data forwarder server re-transmits the packets to the alternate destination.
Separate VCCs are needed to each of these servers, and each requires its own packet format. Thus, an attempt to send a short packet to a hitherto unused address can result in ten or more ATM level transactions. Also, when a station swaps between using the data forwarder service and a point-to-point connection, there is a risk that its packets will arrive out of order. Since mis-ordering does not occur in shared media LAN segments, the ATM Forum is proposing an extra protocol to flush one path before the other is used.
Servers are notoriously difficult to engineer; they have a high start-up cost for small systems and they don't scale well. The present invention simplifies greatly a LAN emulation over an ATM network without the use of servers and will help wide acceptance of ATM networks to integrate existing LANs.


A method for the production of titanium metal from titanium-bearing ore. The method comprises leaching said ore or a concentrate thereof with an aqueous solution of a hydrogen halide; separating solids from the leach solution, to provide a leachate solution. The leachate solution may be subjected to extraction with an immiscible organic phase. Titanium halide is separated from the organic phase by stripping. Preferably, the titanium halide is titanium tetrachloride.

The present invention relates to methods for the separation of titanium from ore, especially iron-bearing ore e.g. ilmenite ore. In embodiments of the invention, the method relates to the recovery of titanium tetrahalides, especially titanium tetrachloride from solutions. In further embodiments, the invention relates to recovery of titanium metal from such ore.
Many processes are known for the recovery of titanium dioxide from ores. Ilmenite, which contains mainly titanium oxide and iron oxide values, often is employed in such processes. The majority of processes for the recovery of titanium dioxide from ores involve digestion of the ore in a mineral acid, such as hydrochloric acid or sulphuric acid, to remove at least the titanium values from the ore. In such processes, however, the purity of the titanium dioxide produced is about 90-95%, and hence further purification procedures may be required to produce a pigment grade product, which adds considerably to the cost. Many of the further purification procedures involve techniques that are environmentally unacceptable without extensive procedures to treat various solutions and solids obtained. Such treatment processes tend to be costly.
Processes for the recovery of titanium dioxide from ilmenite in high purity and high yield are known. One such process is described in U.S. Pat. No. 3,903,239 of S. A. Berkovich, which discloses a process which comprises contacting ilmenite, or a concentrate thereof, in particulate form with concentrated hydrochloric acid at a temperature of about 15-30xc2x0 C. to solubilize and leach from the ore at least 80%, preferably at least 95%, of the iron and titanium values. The leaching operation may be carried out over an extended period of time, typically from 3-25 days, depending on the technique employed and the quantity of iron values to be recovered. Leaching techniques include counter-current flow or the use of closed cycle loops in which hydrochloric acid is continuously passed through a bed of the ore. The leaching operation is exothermic, and the reactants are maintained in a temperature range of 15-30xc2x0 C. by cooling, if necessary.
The ilmenite or similar ore used in the process may be treated as such or may be beneficiated to form a concentrate in any desired manner. Ilmenite generally contains TiO2.FeO with varying amounts of Fe2O3 and gangue materials, usually silicates, alumina, lime and magnesium. Beneficiation may be employed when the ore is of low TiO2 content.
The ore or concentrate may be pre-treated prior to contact with the concentrated hydrochloric acid to increase the rate of dissolution of the titanium and iron values during the leaching step. Such pre-treatment may include an initial oxidation at elevated temperature, such as from 600-1000xc2x0 C., in the presence of air and/or oxygen to split the TiO2.FeO followed by reduction of at least part of the iron oxide with carbon or carbon monoxide. This is a smelting step, with slag from the smelting step being fed to the leaching step and pig iron being marketed.
Subsequent to the leaching step, it is necessary to convert any ferric iron in the solution to ferrous iron, which is typically achieved by reduction of the ferric iron in the leach liquor with a gaseous reducing agent e.g. sulphur dioxide. The conversion of ferric iron to ferrous iron in this manner is essential in view of the affinity of titanium dioxide for ferric iron and the difficulty in separating ferric iron from titanium dioxide.
The solution of titanium chlorides and ferrous chloride which is thus obtained, and which may contain minor quantities of gangue metal chlorides, typically calcium and magnesium materials, is then mixed with water to cause hydrolysis of the titanium chlorides. A seeding amount, generally about 1-2%, by weight of the titanium oxyhydrate to be precipitated (TiO2.3H2O) is included in the mixture. Titanium oxyhydrate precipitates from the mixture. The hydrolysis is carried out using a quantity of water at least sufficient to precipitate substantially all of the titanium values from the solution but insufficient to cause precipitation of other metal oxides or hydroxides. The titanium oxyhydrate that is precipitated from the mother liquor is then washed substantially free of entrained mother liquor and dried. The washed precipitate is converted at elevated temperature, typically 700-1000xc2x0 C., in the presence of air and/or oxygen into the anatase or rutile form of titanium dioxide.
Alternative methods that require less treatment of solution and solids to ensure environmental acceptance and/or are less expensive in achieving environmental acceptance, as well as producing titanium and other products of high value e.g. high purity, are required.
A method for the separation of titanium, and for production of titanium metal, from titanium-bearing ore that involves a reduced number of steps has now been found.
Accordingly, one aspect of the present invention provides a method for the separation of iron values from titanium-bearing ore, comprising the steps of:
a) leaching said ore, or a concentrate thereof, with an aqueous solution of a hydrogen halide;
b) separating solids from the leach solution obtained in (a), to provide a leachate solution;
c) subjecting the leachate solution to extraction with an immiscible organic phase that selectively extracts iron values into said organic phase, titanium values in the leachate solution selectively remaining in the aqueous leachate solution.
Another aspect of the invention provides a method for the production of titanium metal from titanium-bearing ore, comprising the steps of:
a) leaching said ore or a concentrate thereof with an aqueous solution of a hydrogen halide;
b) separating solids from the leach solution obtained in (a), to provide a leachate solution;
c) subjecting the leachate solution to extraction with an immiscible organic phase having a boiling point that differs from the boiling point of the titanium halide in the leachate by an amount that permits separation thereof by fractional distillation, said organic phase being stable with respect to the titanium halide; and
d) stripping titanium halide from the organic phase obtained in step (c) by heating to volatilize the titanium halide and effect separation from the organic phase.
A further aspect of the invention provides a method of separating a titanium halide from a concentrated aqueous solution of the titanium halide, said titanium halide being in a concentration such that the titanium halide is substantially stable in said aqueous solution, comprising:
a) admixing said aqueous solution with an organic phase having a boiling point that differs from the boiling point of the titanium halide by an amount that permits separation thereof by fractional distillation;
b) separating the organic phase so obtained from the aqueous solution; and
c) heating the organic phase and stripping titanium halide therefrom.
Yet another aspect of the invention provides a method for the separation of titanium from a titanium-bearing ore, said ore containing iron, comprising the steps of:
a) leaching said ore, or a concentrate thereof, with an aqueous solution of a hydrogen halide in the presence of an oxidising agent; and
b) effecting a separation of titanium dioxide obtained in step (a) from said solution.
A further aspect of the invention provides a method of forming a titania-rich slag from a titanium-bearing ore that contains iron, comprising the steps of:
a) calcining the ore under oxidizing conditions to eliminate sulphur from said ore, said calcining being carried out at a temperature of at least 1200xc2x0 C.;
b) subjecting the hot calcined ore of step (a) to reducing conditions in the presence of CO;
c) transferring the hot reduced calcined ore obtained in step (b) to a smelting step;
controlling the reducing conditions and the smelting step to obtain pig iron and a titania-rich slag with a predetermined iron content.
Another aspect of the invention provides a method of forming a titania-rich slag from a titanium-bearing ore that contains iron, comprising the steps of:
a) calcining the ore under oxidizing conditions to eliminate sulphur from said ore, said calcining being carried out at a temperature of at least 1200xc2x0 C.;
b) subjecting the hot calcined ore of step (a) to reducing conditions in the presence of CO;
c) transferring the reduced calcined ore obtained in step (b) to a leaching step in an aqueous solution of weak sulphuric acid; controlling the reducing and leaching conditions to obtain a titania-rich material having less than 5% by weight of the iron content of the ore.
A further aspect of the invention provides a method for the separation of iron and titanium values from an iron/titanium ore, comprising the steps of:
a) leaching said ore, or a concentrate thereof, with an aqueous solution of a hydrogen halide in the presence of an oxidising agent; and effecting a separation of titanium dioxide obtained from said solution. b) subjecting the aqueous leach solution so obtained to extraction with an immiscible organic phase that selectively leaches iron values into said organic solvent.
Yet another aspect of invention provides a method for the separation of iron values from titanium-bearing ore, comprising the steps of:
a) leaching said ore, or a concentrate thereof, with an aqueous solution of a hydrogen halide;
b) separating solids from the leach solution obtained in (a), to provide a leachate solution;
c) subjecting the leachate solution to extraction with an immiscible organic phase that selectively extracts iron values into said organic phase, titanium values in the leachate solution selectively remaining in the aqueous leachate solution.
d) subjecting the aqueous raffinate so obtained to steps to separate TiO2 therefrom.
Processes for the recovery of titanium dioxide from ilmenite, with high purity in high yield, are known. Techniques for treating the ilmenite ore, optionally to form concentrate and/or for beneficiation of the ore are known. In some instances, it is possible to treat the ore or concentrate with concentrated hydrochloric acid solution to effect a leaching of titanium values from the ore or concentrate. In other instances, it is necessary or desirable to subject the ore or concentrate to a smelting step in the presence of carbon and/or fluxing agents, and to then separate a slag from the smelting process which is then subjected to the leaching step.
One aspect of the present invention is directed to the step of recovery of titanium values from the leaching solution. The leaching solution is a mixture of aqueous hydrochloric acid containing titanium values, and other soluble material and solid materials, particularly residues of the concentrate and/or slag from which the titanium values have been leached. A liquid/solid separation step is conducted, to separate a leachate solution from solids.
The leachate so obtained is treated, according to an aspect of the present invention, with an organic phase. The titanium values in the leachate are in the form of titanium halide, especially titanium tetrahalide which, if hydrochloric acid is used in the leaching step, will be titanium tetrachloride.
In one aspect of the invention, the organic phase is selected so that iron values are selectively separated into the organic phase. Thus, an organic/aqueous separation is effected, with the iron values being in the organic phase and titanium values remaining in the aqueous phase. Preferably, iron values are separated almost to the exclusion of other values in the leachate solution, or with values readily separated therefrom, so that iron products especially iron oxides, may be obtained in high purity. Vanadium and other metal values that may be present in the leachate are preferably retained in the aqueous phase.
Examples of the organic phase are phosphoric, phosphoric acid and phosphinic acids, esters oxides thereof. Specific examples are tri-n-butyl phosphate and di-2-ethylhexyl phosphoric acid. The organic phase preferably contains a diluent e.g. a hydrocarbon, an example of which is a kerosene.
The organic phase may be stripped from the iron values and recycled. The iron values may then be subjected to pyrohydrolysis, or other steps, to recover iron e.g. as iron oxides. Preferably HCl is obtained as a by-product which is recycled to the step of leaching of ore or concentrate described above.
In a second aspect, the organic phase is selected such that the titanium halide is soluble in the organic phase. Moreover, the organic phase is selected such that the organic phase and titanium halide may be separated by fractional distillation. The organic phase may be selected to have a higher or lower boiling point that the titanium halide. The preferred titanium halide is titanium tetrachloride. In embodiments of the invention, the boiling point of the organic phase differs by least 50xc2x0 C., and especially at least 75xc2x0 C., from the boiling point of the titanium halide. The organic phase must be immiscible with the aqueous solution, such that it forms a second layer so that separation may be effected.
The titanium halide is extracted from the aqueous solution into the organic phase, to effect removal of the titanium halide from the aqueous solution. Such extraction may be carried out in a continuous operation or in a batch operation.
The organic phase may be, for example, a crown ether, phosphine acid, ester or oxide, or tertiary or quarternary ammonium salt.
The organic phase containing the titanium halide is separated from the aqueous solution and from any solid matter, and is then subjected to a step to separate the titanium tetrachloride. In the separation step, the organic phase containing the titanium halide is heated to effect the separation of the titanium halide. This is preferably accomplished by volatilization of the titanium halide, especially if the halide is chloride although for any particular tetrahalide the organic phase may be selected to effect volatilization of either the titanium tetrahalide or the organic phase. In addition, the organic phase should be selected so that it has a flash point that is acceptable under the operating conditions, preferably a flash point above the temperature used in separation. The organic phase needs to be stable with respect to the aqueous solution and to the titanium tetrahalide at the operating conditions.
The aqueous solution remaining after extraction may be subjected to known procedures for recovery of iron or other metal values or procedures described above, and for recovery and recycle of acid used in the leaching step. For example, iron oxide (Fe2O3) may be recovered and the acid e.g. HCl, recycled. The organic phase is preferably recycled back to the extraction step, and reused.
The titanium tetrahalide may be subjected to purification steps, if necessary. However, if the titanium tetrahalide is volatilized, it may be of acceptable purity for many end-uses. The titanium halide may be used as such or subjected to further processing steps e.g. to form titanium metal. Techniques for the conversion of titanium tetrahalide and titanium dioxide to titanium metal are known.
In embodiments of the invention, essentially all of the iron of the feed material i.e. titanium-bearing ore or concentrate is dissolved by the HCl. Thus, sufficient HCl has to be provided. In order to minimise the amount of HCl required in the process, the iron chloride (e.g. H+FeClxe2x88x924 or a chloride of iron e.g. FeCl3) produced in the process is subsequently subjected to pyrohydrolysis to regenerate the HCl. The iron is converted into an iron oxide product (Fe2O3). By controlling the composition of the iron chloride solution before subjecting it to pyrohydrolysis, it is possible to produce a high grade iron oxide suitable for use in pigment production. If this is not economic, the disposal of iron oxide becomes an environmental problem. In such instances, it is advantageous to remove the iron and upgrade the titanium ore before subjecting it to treatment with HCl. This alternative also has the advantage of decreasing the size of the hydrometallurgical plant for a given production of titanium.
In another aspect of the present invention, the ore or concentrate is leached in aqueous solution in the presence of an acid and an oxidizing agent. A variety of oxidizing agents may be used, including air, hydrogen or other peroxides, or sodium or other perchlorates. The oxidizing agent should be selected to minimize any contamination of the solution with cations that have an adverse effect on other process steps.
In the aqueous solution, the titanium is converted to titanium dioxide and the iron is solubilized. The acid is preferably a hydrogen halide, especially HCl. If the acid is HCl, the concentration of acid may be controlled, in the presence of the oxidizing agent, to convert iron into H+FeClxe2x88x924, which is soluble in the aqueous solution. Subsequently, liquid/solid separations may be effected, to separate TiO2 including separation of TiO2 from tails from the aqueous solution. The aqueous solution may be treated for recovery of HCl and iron e.g. as Fe2O3.
One of the concentration alternatives for the treatment of the ilmenite ore or physically beneficiated ilmenite is the production of a titanium-rich slag and pig iron from it, with the titanium-rich slag being subjected to HCl leaching for titanium recovery and the iron being sold as a foundry-grade pig iron.
The processing of ilmenite to produce titania slag and pig iron is known. In such processing, the concentrate is calcined in a rotary kiln under oxidising conditions at about 1200-1300xc2x0 C. to eliminate sulphur in the ilmenite concentrate. The product is cooled and fed to an electric furnace with coal/coke as reductant to reduce the iron and produce a molten slag and pig iron. The electric furnace smelting takes place at about 1650xc2x0 C. Disadvantages of the current processing method include (i) the energy in the calcine from the rotary kiln is lost and the product must be re-heated to the smelting temperature in the electric furnace with electric power; (ii) the reduction in the electric furnace produces a lot of CO gas, which often results in the foaming of the slag and process control is difficult; and (iii) the reduction of the iron oxide by carbon to produce CO is endothermic and the heat required is supplied by electricity.
The production of electricity from fuel is typically energy inefficient, to the extent of about 30% conversion, and therefore the process is very energy intensive.
In aspects of the present invention, the use of energy is reduced. In a preferred embodiment, the reduction of the calcine is carried out prior to the electric furnace smelting. This may be carried out in a second reducing section of the calcining kiln or a separate kiln following the calcining kiln. The reduction is done by reducing gases produced by the partial reduction of CO (produced in the electric furnace) and/or by partial combustion of fuel. The reduced calcine so produced is transferred hot from the reduction kiln to the electric furnace, with any additional reductant if required. This saves the energy lost in cooling the calcine and improves the efficiency of use of fuel for the iron oxide reduction. The smelting of reduced calcine requires less electric energy, produces very little gas in the electric furnace and makes the electric furnace easier to control. The reduction in the reduction step and the electric furnace are controlled to provide a desired iron level in the slag. This controls the slag melting temperature. Depending on the composition of the ilmenite concentrate, the smelting may be carried out at lower temperatures e.g. 1550xc2x0 C., thereby conserving more energy compared to the current processing.
Alternatively, the process of smelting and production of molten titania-rich slag and pig iron in the final step of the above process may be replaced by a leaching process for removing the reduced iron produced in the reduction step. This may be carried out by dissolving it in a weakly acidic chloride solution, with aeration, to dissolve the iron and leave a titania-rich oxide product suitable for HCl leaching, as described herein. The advantage of this approach is that the reduction can be carried out at lower temperature e.g. about 800xc2x0 C. instead of about 1000xc2x0 C. and the energy of smelting in the electric furnace is conserved. In addition, in this embodiment, it is possible to eliminate over 95% of the iron and minimise the iron fed to the HCl leaching process. In comparison, there is about 90% iron removal in the smelting route, as some iron has to be left behind to provide a fluid slag in the smelting step. This minimises the usage of HCl and the subsequent regeneration of the HCl for re-use in the process.
In the production of titanium and TiO2 pigment, it is necessary to produce titanium chloride by chlorination of titanium dioxide-containing materials e.g. titania slag and rutile concentrate, at about 900xc2x0 C. in the presence of coke. By using the present process, the titanium chloride may be produced by leaching the titania containing material with HCl followed by extraction and separation of titanium chloride. The high temperature chlorination is replaced by lower temperature operations and avoids the formation of environmentally unacceptable dioxins which can form in the high temperature chlorination. In addition, the purity of the titanium chloride produced in the present process will be improved and will require less purification or even no purification.
In various aspects of the invention, there is provided a process in which titanium-bearing ore or concentrate, generally after having been subjected to a smelting step, is subjected to a leaching step using aqueous hydrochloric acid. A leach solution containing titanium and iron values, and other metallic values depending on the particular ore, is obtained. A liquid/solid separation step is conducted. The solids may be subjected to other separation steps but generally will be gangue.
In preferred aspects of the invention, the leachate solution is subjected to extraction with organic phase to extract iron values, as described above. Such phase may contain 100-200 g/l of iron, or more. Examples of the organic phase are tri-n-butyl phosphate and di-2-ethylhexyl phosphoric acid, with other examples being described above. The organic phase with iron values is then subjected to steps to separate and recover the organic phase, which is recycled to the step of extraction of the leachate solution. Iron values, which are in the form of chlorides are recovered, especially by pyrohydrolysis to yield iron oxides and HCl. The HCl is recycled to the leaching of the ore or concentrate. Iron values of high purity may be obtained.
The leached aqueous solution or raffinate may be treated to separate vanadium and other metallic values, depending on the particular ore, especially by precipitation, to provide a raffinate rich in titanium, and preferably with high-purity titanium values. The titanium values are in the form of the chlorides viz TiCl4, which may be subjected to steps to form TiO2, which is recovered. High purity TiO2 may be obtained, which may be of sufficiently high purity for use as such.
As an alternative, the raffinate rich in titanium values may be subjected to further extraction, using an organic phase that is immiscible in water and which has a boiling point that differs from the boiling point of the titanium value, e.g. titanium tetrachloride by an amount to permit fractional distillation. The titanium value is extracted from the aqueous solution of the raffinate into the organic phase and then recovered by distilling or flashing off either the organic phase or the titanium value, depending on the respective boiling points. Titanium metal may then be recovered from the titanium halide.
The by-products of such a process are minimized, and may be treated by known but relatively simple techniques.
An alternative separation of titanium values is to separate the titanium as TiO2 directly from the leaching of the ore or concentrate, by leaching in the presence of an oxidizing agent and separating the TiO2 formed from the solution and from other solids therein.
The present invention provides methods for the separation of titanium from titanium-bearing ores, especially ilmenite. In particular, the invention provides methods for production of titanium tetrahalides, especially titanium tetrachloride, and TiO2 with improved purity and/or such that related steps in an overall process, including recovery and recycle of materials, may be simplified and be more cost effective. In particular, the volumes of liquid and solids that must be handled in the overall separation process may be reduced, and associated hardware may be reduced in size. Such improvements may be of significant economic benefit.

Separation of titanium halides from aqueous solutions


A shared storage configuration system for use in a computer system includes a plurality of processing modules and a plurality of shared storage modules. Each of the processing modules has at least a main storage unit, a central processing unit, and a connection unit for connection to a system bus. Each of the shared storage modules has a shared storage unit and a connection unit for connection to the system bus. A space inherent in the processing modules is accessible by physical addresses of the central processing units. The shared storage space is accessible either in program mode by the physical addresses of the central processing units or in direct memory access mode by relative addresses translated from the physical addresses output by the central processing units.

1. Field of the Invention
The present invention relates to a a system for configuring shared storage and a shared storage duplicating system for use with a multiprocessor system in which processor modules and shared storage modules are connected by a system bus.
2. Description of the Related Art
A shared storage device of a multiprocessor system stores instructions and data necessary for processing by multiple processor modules. These processor modules frequently access the shared storage device. If the frequency of access to the shared storage device is high, the number of processor modules which can be built into the system will be limited and consequently, the system's performance will be limited. Furthermore, abnormality in one processor module is apt to be directly linked to abnormality within the whole system. Thus, a shared storage configuration system is desired which permits efficient access to the shared storage device and decreases access frequency.
Specifically, a shared storage for a fault tolerant system requires duplication. However, as the duplex configuration of the shared storage is fixed by hardware, flexible control is not allowed in duplicating the configuration. Besides, in accessing a duplex memory, the software monitors the access as a duplex access, thus being subject to a large process load caused by a duplex write. Therefore, an improved duplicating method is in great demand which allows a change in a duplex configuration and a reduction in load on software during the duplex access.
A conventional multiprocessor system comprises a plurality of processor modules and a plurality of shared storage modules which are connected by a system bus for transfer of information, thereby forming a computer system.
In such a multiprocessor system, instructions and data necessary to a central processing unit of each processor module are stored in the shared storage modules. Hence, each processor module forms a TCMP (Tightly Coupled Multiprocessor) system which frequently accesses the shared storage modules.
In addition, a shared storage duplicating method is indispensable for realizing a fault tolerant multi-processor system capable of continuous operation even when a fault occurs in a part of the system being operated.
A duplex configuration of a conventional shared storage is determined by the hardware, and an abnormal condition in one of the duplex storages is corrected immediately by a duplicating write where the same data are written, according to a write instruction of a processor based on the software, into a pair of shared storage modules specified as a duplex.
With the TCMP system in which each processor module frequently accesses the shared storage modules, however, there is a limit to the information transfer capability per unit time of the system bus. Thus, if the number of accesses increases, the number of processor modules which can be built into the system will be limited to a considerably small number. Consequently, system performance will also be limited.
In implementing a fault-tolerant computer system which is able to continue functioning without going down even when a fault occurs in part of the system, problems which arise with the conventional system, if an abnormality occurs in one processor module due to an access error, the system bus will be released after a delay with overhead occurring in the other processors due to the extremely frequent access to the shared storage module, which may cause an abnormality of the whole system to occur.
Moreover, in the conventional system, the memory area accessible by the central processing unit of a processor module is limited by the physical addresses of the central processing unit, and thus the area outside the physical address capacity cannot be used as a memory space area. Therefore, it has been extremely difficult to build a computer system that requires vast memory space, for example, one for processing a large-scale data base.
However, shared storage duplication in a fault-tolerant system does not require duplication of all memory areas, but performs duplication only of specific memory areas as required.
However, in the duplicating method in the prior art technology, the duplex configuration of a shared storage is fixed and determined by the hardware. Therefore, if the size of the memory areas to be used during the duplicating process fluctuates during system operation, the system must be stopped so that the duplex configuration can be changed by the hardware. This causes a problem in that the duplex configuration cannot be determined flexibly.
In the duplicating method of the prior art technology, software recognizes a duplex access on accessing a duplex memory and monitors the state of the access until data are written twice in the duplex shared storage. Thus, the load on the software becomes large and system efficiency is reduced.

System for allocating and accessing shared storage using program mode and DMA mode


N+-type semiconductor regions 12d are formed on a front surface side of a p−-type layer 12c of a semiconductor substrate 12, and these n+-type semiconductor and p−-type semiconductor constitute photodiodes. A metal wire 14 electrically connected to an isolation region 12e is formed on a first insulating layer 13. The metal wire 14 is provided so that its edge covers pn junction portions (interfaces between p−-type layer 12c and n+-type semiconductor regions 12d) exposed on a light-incident surface of the semiconductor substrate 12 (p−-type layer 12c), above the pn junction portions, and is of grid shape. The metal wire 14 is grounded and the isolation region 12e is set at the ground potential.

An example of the known radiographic imaging apparatus of this type is one having a fiber optical plate (hereinafter referred to as FOP), a scintillator disposed on one surface of the FOP, and an MOS image sensor disposed opposite to the scintillator on the other surface of the FOP (e.g., reference is made to Patent Document 1).
Another example of the known radiographic imaging apparatus is one having a photodetector array in which photodetectors for photoelectric conversion are arrayed in a one-dimensional or two-dimensional pattern, and a scintillator formed directly on light-incident surfaces of the photodetectors (e.g., reference is made to Patent Document 2).
[Patent Document 1] Japanese Patent Application Laid-Open No. 2000-28735
[Patent Document 2] PCT International Publication WO98/36290

Solid-state imaging device and radiotion imaging system


Disclosed are a method and an apparatus for solving mask precipitated defect issue. A gas is purged into a photomask reticle assembly for diffusing precipitated defects out of a photomask in the photomask reticle assembly. A metal shielding assembly enclosing the photomask reticle assembly is provided for reducing precipitated defects and damages to the photomask. In an illustrative embodiment, the metal shielding assembly comprises an upper metal shielding, a pellicle frame of the photomask reticle assembly, side support frames of the photomask reticle assembly, a top cover, a handle, and a handle cover.

The present disclosure relates in general to semiconductor manufacturing technology, and more particularly, to reducing or solving precipitate defects associated with photolithography photomasks.
Photomasks, or reticles, are commonly used for photolithography in semiconductor manufacturing. Photomasks are typically made from very flat pieces of quartz or glass with a layer of chromium deposited on one side. The pattern being used to transfer an image to a wafer on BIM or PSM masks during a photolithography processing. While contamination of photomasks has always been a problem, high precision masks, such as are used in photolithography having wavelengths equal to or less than 248 nm, are particularly susceptible to defects.
One type of photomask contamination is referred to as haze contamination. Haze contamination is a precipitant formed from mask cleaning chemical residual or impurity of fab or tool environment cross exposure. For example, when a solution including ammonium (NH4) and sulfate (SO4) is used to clean a photomask, contamination becomes apparent when the photomask is exposed to a short wavelength UV light, such as 248 or 193 nm. Haze contamination maybe isolated by purging the photomasks with a general gas, such as nitrogen or clean dry air. Purging typically involves diffusing the gas into a reticle pod via a gas inlet and diffusing impurity materials, such as ammonium and sulfate, out of the reticle pod.
Photomasks also suffer from other defects, such as those caused from electrostatic discharge (ESD). ESD can damage the pattern on the photomasks, resulting in a defected image produced on the wafers.
Therefore, a need exists for a method and an apparatus that minimizes haze contamination. Also, a need exists for a method and an apparatus that reduce damages of photomasks due to ESD.

Method and apparatus for solving mask precipitated defect issue

Taiwan Semiconductor Manufacturing Company, Ltd.


A printed-circuit board and a method for the precise assembly of electronic components on a surface of the printed-circuit board, the electronic components being electrically and conductively attached to printed-circuit board by a reflow soldering technique. For this purpose, a printed-circuit board is used that has sections for receiving electronic components on its surface. The sections being at least partially adapted to the outside contour of respective electronic components. The sections are configured as slotted contours or grooves and shaped to secure that the electronic components mounted after the application of solder paste are held in their desired positions prior to the actual soldering process. In addition, the assembled printed-circuit board can be connected to a housing composed of dome-type extensions of an at least partly deformable material. The extensions engage in cutouts provided in the printed-circuit board and pass through the latter. A positive-linkage and/or frictional housing/printed-circuit board connection is established by deformation of the extensions. Further, an overvoltage protection plug for terminal blocks of the telecommunication technique with a voltage surge arrester can be mounted that combines the two functions "earthing contact" and "fail-safe contact" in one part.

It is known to mount the voltage surge arresters by a reflow soldering technique on the printed-circuit board and to contact the other electronic components, such as PTC'S, varistors and diodes as chip components by means of a conventional clamping technique. Therein problems exist with the precise positioning of the voltage surge arrester, when the latter is not held in the desired position during the soldering process, and therefore contact problems or difficulties during further processing or assembly of the printed-circuit board may occur.
By various techniques of assembling different components on the printed-circuit board, several steps are required for contacting. Further, additional contact lugs are required for the assembly of the printed-circuit board with the other components (PTC's and varistors), thus increasing the material and manufacture costs.
In reflow soldering techniques it is common to apply solder material on the printed-circuit boards at positions intended for receiving an electronic component. Thereafter, the respective component is mounted on the solder material still being in a pasty condition, and then the completely assembled printed-circuit board is heated, until the solder material melts, and after cooling down, the electronic component is held in position by the re-solidified solder material and is electrically contacted.
As long as the solder material does not yet effect an intense connection of the electronic component to the printed-circuit board, that is immediately after placing the electronic components, the respective electronic component may slip and come out of the desired position. Since the reflow soldering technique is usually performed in continuous-heating furnaces, such as they are for example known from DE 40 16 366 C2, provisions have to be taken during transportation of the preassembled printed-circuit board, such provisions preventing the electronic component from slipping away from the desired position by movements or vibrations.
In order to prevent such slipping away, there is known for example from EP 0 540 497 A2 the utilization of a matrix which can however only determine the surface shape of the solder applied to the solder positions. Fixation of the component at least to a certain degree is not possible by this method. Positioning is to be facilitated by that the generated solder positions have a plane surface.
The utilization of an adhesive to fix the components to an printed-circuit board is disclosed in DE 41 26 913 A1. Therein the connection of the respective component to the printed-circuit board is established by an adhesive. Thereafter the actual soldering process is performed, and the complete connection is finally accomplished. In addition to the required adhesive, the supply of which necessitates higher expenditures for the printed-circuit board assembly, high requirements have to be met by the use of adhesive. Since the latter is exposed to high temperatures during soldering, it may come to damage the solder due to solvent possibly contained in the adhesive.

Printed-circuit board and method for the precise assembly and soldering of electronic components on the surface of the printed-circuit board


An exhaust fan unit of a heating, ventilation, and/or air conditioning (HVAC) system includes an outer fluid path of a nozzle assembly of the exhaust fan unit defined by and between an outer wall of the nozzle assembly and an inner wall of the nozzle assembly, an inner fluid path of the nozzle assembly defined by and radially inward from the inner wall, and a plurality of entrainment ports extending from the outer wall to the inner wall and configured to enable environmental air to pass to the inner fluid path, where each entrainment port includes a bottom surface that tapers downwardly from the inner wall to the outer wall.

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
A wide range of applications exists for HVAC systems. For example, residential, light commercial, commercial, and industrial systems are used to control temperatures and air quality in residences and buildings. In certain HVAC systems, exhaust gases or fumes from a space being conditioned by the HVAC system are expelled to a surrounding environment via an exhaust fan unit, sometimes referred to as a laboratory exhaust unit. It is now recognized that traditional exhaust fan units may be inefficient in removing, diluting, and dispersing exhaust gas, and may be susceptible to environmental and other damage. For example, traditional exhaust fan units may not provide adequate protection against gas leakage, flow control, dilution of contaminants, and evacuation to reduce entrainment through other HVAC intake systems or direct contact. Furthermore, traditional exhaust systems may deposit contents of the exhaust gas in small, concentrated areas of the surrounding environment.

Exhaust fan unit of a heating, ventilation, and/or air conditioning (HVAC) system


The present invention provides a protein, specifically Parietochloris incisa acetohydroxyacid synthase, and methods for producing branched-chain amino acid in a cell. The present invention further provides polypeptides and polynucleotides useful for conferring herbicide resistance in a cell or an organism. In particular, the present invention discloses a mutated acetohydroxyacid synthase which is resistant to herbicides.

Branched-chain amino acids (BCAAs), namely leucine, isoleucine and valine, are synthesized by plants, algae, fungi, bacteria and archaea, but not by animals. BCCAs are essential amino acids for humans and are used clinically for the treatment of burns and hepatic encephalopathy as well as for increasing muscle mass. The enzymes of the BCAA biosynthetic pathway are potential targets for the development of herbicides, fungicides, and antimicrobial compounds. Some of the most popular herbicides (e.g. sulfometuron methyl, SMM), act by inhibiting the first common enzyme in the BCAA biosynthetic pathway, acetohydroxyacid synthase (AHAS). Since AHAS is required for the synthesis of all three BCAAs, its inhibition is detrimental to the organism and effectively inhibits its growth. Plant and green algal AHAS are localized in the chloroplast and fungal AHAS in the mitochondria, although the genes may be present in the nuclear or organelle genome. In cases of nuclear-encoded genes, the enzyme is transported to the target subcellullar compartment by an additional, poorly conserved, N-terminal targeting peptide.
Microalgae are one of the richest sources of long-chain polyunsaturated fatty acids (LC-PUFAs). The green freshwater microalga Parietochloris incisa (Trebouxiophyceae) is the only microalga able to accumulate extraordinary high amounts of LC- PUFA arachidonic acid (ARA)-rich triacylglycerols (TAG). When P. incisa is cultivated under nitrogen starvation, the fatty acid (FA) content of the alga is over 35% of dry weight; ARA constitutes about 60% of total FAs, and over 90% of cell ARA is deposited in TAG, making it the richest green dietary source of ARA. LC-PUFAs include the ω3-fatty acids, eicosapentaenoic acid (EPA, 20:5ω3), docosahexaenoic acid (DHA, 22:6ω3), ω6-fatty acid, arachidonic acid (ARA, 20:4ω6) and dihomo-γ-linolenic acid (DGLA, 20:3ω6). LC-PUFA are major components of membrane phospholipids of the retina, brain and testis and are predominant in the human brain and breast milk (specifically ARA and DHA). ARA is necessary for normal fetal growth and for cognitive development in infants and is also the primary substrate in eicosanoids biosynthesis, which regulates many physiological processes such as homeostasis, reproduction, immune and inflammatory responses.
Use of antibiotic resistance genes as selection markers in transformation processes presents numerous environmental and health risks, as well as regulatory difficulties that define the organism as genetically modified (GM). Thus, a selection system based on mutation(s) of an endogenous gene(s) is highly advantageous. It has been reported that mutant forms of AHAS exhibit herbicide resistance in yeast, higher plants and green algae, where most of the characterized AHAS herbicide resistances is due to a single or double amino acid change from the wild-type enzyme sequence. At least 17 different amino acid substitutions in AHAS are known to confer resistance to growth inhibiting herbicides. For example, in tobacco, a resistant mutant with a single amino acid change of Tryptophan557, within a conserved region of AHAS, was found to be insensitive to inhibition by two sulfonylurea herbicides, chlorsulfuron and SMM. In addition, corresponding Trp residue mutations were shown to be important for AHAS SMM resistance of Escherichia coli, Mycobacterium tuberculosis, Brassica napus and the red microalga Porphyridium sp.
There remains an unmet need for the development of cells, in particular microalgal cells which are capable of producing LC-PUFA in large scale systems and which are resistant to herbicides, using methods which do not classify the organism as genetically modified.

Compositions and methods for conferring herbicide resistance

Ben-Gurion University of the Negev Research and Development Authority


The present invention relates to novel 3-benzylidene-1-carbamoyl-2-pyrroridone analogues having advantage anti-inflammatory activities, which is represented by the formula: ##STR1## wherein R.sup.1 and R.sup.2 each is independently hydrogen, alkyl, alkoxy, or halogen; R.sup.3 is hydrogen or acyl; R.sup.4 is hydrogen, alkyl, hydroxy, alkoxy, cyano, or halogen; R.sup.5 and R.sup.6 each is independently hydrogen, alkyl, aryl, aralkyl, heterocyclic group, substituted or unsubstituted amino, or OR.sup.7 wherein R.sup.7 is hydrogen, alkyl, aryl, acyl, or aralkyl, or taken together with the adjacent nitrogen atom may form heterocyclic group which may contain N, O, and/or S, and X and Y each is independently O, S, substituted or unsubstituted imino, or substituted or unsubstituted methylene. In more detail, the present invention provides an anti-inflammatory agent which is useful for the treatment of chronic inflammation and has little side effect, e.g., stomach disease.

Prior anti-inflammatory agents of non-steroid type are effective to the improvement in the early stages of rheumatism and acute inflammation, however, have some defects of being no effective to progressed rheumatic diseases such as osteonecrosis, the improvement in chronic rheumatic diseases, or the treatment of arthrosteitis etc., and of having potent activities to induce gastric ulcer caused by the inhibition of the production of prostaglandin E.sub.2 (PGE.sub.2).
Recently it has been revealed that leukotriene (LT), esp. LTB.sub.4 etc., which is a metabolite produced via the metabolism of arachidonic acid caused by 5-lipoxygenase, is an important mediator in inflammation reaction. Furthermore, it has been suggested that the cause of inflammation relates to IL-1 which is a kind of cytokines and that also chronic rheumatism is much influenced by cytokines such as IL-1.
In view of circumstances above, attentions have been paid to compounds having inhibitory activities against the production of LTB.sub.4 and IL-1, as a new type of anti-inflammatory agent. These compounds are much useful than known non-steroidal anti-inflammatories, in respect of that they are expected to have efficacy not only to acute inflammation but also to chronic inflammation, e.g., chronic arthrorheumatism etc.
With an intention to develop such anti-inflammatory agents as described above, a wide variety of compounds are disclosed in specifications of Kokai 58-79944, Kokai 61-257967, Kokai 62-42977, Kokai 1-305028, Kokai 2-4729, Kokai 2-256645, Kokai 2-270865, and Kokai 1-503782.
As stated above, it has been desired to develop anti-inflammatory agents capable of inhibiting the production of mediators relating to inflammation such as PGE.sub.2, LTB.sub.4, and IL-1, however, such an anti-inflammatory agent as being useful for treating chronic inflammation and having little side effect, e.g., stomach disease, has not been developed yet.


A rotating air cylinder is disclosed. The rotating air cylinder, comprises a first master cylinder comprising a first cylinder block, a first sealing assembly assembled in one distal end of the first cylinder block; a cylinder shaft partially received in the first cylinder block; a first piston assembly movably sleeving on the cylinder shaft, wherein the first piston assembly moves longitudinally within the first cylinder block, and rotates relative to the cylinder shaft; a second master cylinder positioned coaxial with the first master cylinder comprising a second cylinder block received in another part of the cylinder shaft; a second sealing assembly assembled in the second cylinder block; a second piston assembly received in the second cylinder block, non-rotatably and slidably connected with the cylinder shaft, wherein the second piston assembly moves longitudinally in the second cylinder block and rotates relative to an axis of the second cylinder block.

1. Technical Field
The present disclosure relates generally to cylinders, and more particularly, to rotating air cylinders.
2. Description of Related Art
Many rotating air cylinders have single master cylinders. The master cylinder may include a cylinder block defining a receiving chamber, a piston and a cylinder shaft. The cylinder block may define openings at opposite ends communicating with the receiving chamber. The piston may be movably received in the receiving chamber, a first end of the cylinder shaft may be fixed to the piston, and a second end of the cylinder shaft may extend out of the cylinder body via one opening. A pressing rod is positioned in the second end of the cylinder shaft to clamp or transfer materials. The pressing rod is driven to rotate and move linearly at the same time. The rotating radius and the linear movement distance of the pressing rod is long. The volume of the cylinder may be relatively large, and a significant amount of space may be needed to enable the cylinder to work.
Therefore, there is room for improvement within the art.

JI ZHUN PRECISION INDUSTRY (HUI ZHOU) CO., LTD.


A sign assembly supported above a supporting surface includes at least one sign frame, an upstanding hinge rod assembly mounted on the supporting surface, and a hinge plate rotatably supported by the hinge rod assembly is connected to one frame side. The other frame side connects to a second plate that is supported by a pre-installed post or another hinge rod assembly. The angles of the one or more sign frames can be changed to meet installation requirements until the post mounts and/or hinge rod assemblies are fixed relative the supporting surface.

The present invention relates to information and advertising signs and more particularly to a new arrangement for supporting one or more display sign assemblies that include a vertical post, installed in or on the ground, concrete, macadam, or other surface material.
One result of our societies dependence on the automobile is the growing popularity of drive-through and parking facilities for all kinds of services including convenience stores, fast food services, fueling stations, banking, etc. Designs of these facilities, by choice or by law, include many safety devices intended to avoid or reduce the consequences of automobile impact on walls, curbing, auto stop blocks, and equipment such as automatic vacuum tube canister delivery systems, gasoline dispensers, fast food ordering speaker and communications systems, etc. To avoid or reduce auto collision efforts, designers commonly install bumper guard pipes to protect facilities and equipment from impact. These guards commonly include 4 to 8 inch steel or aluminum pipe painted white or red, capped or filled with a concrete plug, and installed on or into or adjacent the driving surface and standing 3 to 4 feet above the surface. Although these guards provide some degree of impact protection, they provide poor visual protection to the contiguous facility or equipment. In addition, these standard guards provide no advertising value for the facility or services or products provided there.
Some progress and improvements have been made by the present inventor and assignee hereof in combining the U-shaped pipe guards in front of fueling dispensers with a sign assembly mounted on the center leg thereof. See U.S. patent application Ser. No. 09/333,230, filed Jun. 14, 1999 owned by the present assignee.
However, the need exits for a sign assembly that can easily and efficiently mount to a vertical pipe guard regardless of the spacing between adjacent vertical pipe guards or alternately reliably mount in stand along fashion with the same elements used to secure the sign assembly to a pipe guard.


This patent describes a method and apparatus to automatically and accurately winnow down arbitrarily large amounts of electronic information created by a particular population of actors to only those subsets of particular interest by having a causal relationship, even when retrieved documents containing this information do not individually satisfy the search criteria used. An actor in this context is defined as any entity, single or aggregate, capable of creating, distributing, modifying, or receiving digital information. Once identified, this subset of information may, for example, be processed, analyzed, redacted, or destroyed, depending on the context of the system's use.

The volume of electronic information in both personal and corporate data stores is increasing rapidly. Examples of such stores include e-mail messages, word-processed and text documents, contact management tools, and calendars. But the utility, precision and usability of knowledge management and search technology has not kept pace.
The vast majority of searches performed today are still keyword searches or fielded searches. A keyword search involves entering a list of words, which are likely to be contained within the body of the document for which the user is searching. A fielded search involves locating documents using lexical strings that have been deliberately placed within the document (usually at the top) with the purpose of facilitating document retrieval. These data retrieval techniques suffer from two fundamental flaws. Firstly, they often result in either vast numbers of documents being returned, or, if too many keywords or attribute-value pairs are specified and the user specifies that they must all appear in the document, no documents at all. Secondly, these techniques are able only to retrieve documents that individually meet the search criteria. If two or more related (but distinct) documents meet the search criteria only when considered as a combined unit, these documents will not be retrieved. Examples of this would include the case where the earlier draft of a document contains a keyword, but where this keyword is absent from a later version of the same document; or an e-mail message and an entry in an electronic calendar, where the calendar entry might clarify the context of a reference in the e-mail message.
Additionally, the user often requires detailed prior knowledge (before running the search) of keywords likely to occur in any sought-after documents, or even such details as the exact date (or range of dates) on which a message was sent, or who sent it.

Data mining by retrieving causally-related documents not individually satisfying search criteria used


There is provided a signal generation apparatus for generating an output video signal based on an input video signal provided corresponding to an image to be displayed, the output video signal being a signal for driving an image display section including a display area, the display area including a plurality of pixels arranged in a two-dimensional matrix. At a change of the input video signal from low-brightness display to high-brightness display for a portion of the display area including one or more of the pixels, during a period for the signal change, the output video signal being generated for each of the one or more of the pixels in the portion of the display area to obtain a higher brightness than usual for the portion of the display area.

The present disclosure relates to a signal generation apparatus, a signal generation program, a signal generation method, and an image display apparatus.
Images displayed on a display apparatus have a limited brightness range that is affected by design specifications or others of the display apparatus. The images displayed on the display apparatus thus have a reduced dynamic range of brightness, and thus easily give a viewer an impression as being less real.
For improving such image display, Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2009-520241 (hereinafter, referred to as Patent Document 1) describes a technology of selectively increasing a brightness value for any limited bright area in images.

Signal generation apparatus, signal generation program, signal generation method, and image display apparatus


A fish feed dispersing apparatus includes a helical dispersing tube attached to a fish pen with a mounting assembly. The helical dispersing tube has an inlet end that receives fish feed from a source, and includes a number of spaced apertures that disperse the received fish feed. A mounting assembly supports the dispersing tube, and includes two spaced-apart attachment members connected by a plurality of elongate members, and a plurality of hanger subassemblies. Each hanger subassembly has a first end attached to one of the elongate members and a second end that includes a clamp configured to engage the helical dispersing tube. The hangar assemblies are adjustable, and support the helical dispersing tube during use.

The seas and other natural water reservoirs have provided an abundant and stable supply of sustenance for millennia. In recent years, however, over-fishing, inefficient harvesting practices, and environmental stressors have resulted in the depletion or decline of certain fish populations in many regions. At the same time, an increasing human population, increasing standards of living, and an increasing awareness of the health benefits of seafood have increased the demand for fish and fish product.
Advances in aquaculture in general, and fish farming in particular, and improvements in technology have recently been applied to meet world demand for fish product efficiently and at lower costs. Developments in fish farming also reduce the risks associated with over-fishing existing fish populations. In particular, off-shore cultivation systems employing fish cages or fish pens have found some success. Large, submersible fish pens suitable for aquaculture applications are known in the art to aid in the efficient and bio-responsible cultivation of food sources. Fish pens are placed in a natural body of water, such as a lake, river, or ocean, and stocked with young fish or fry, and the fish are fed and maintained until they reach maturity. The fish pens provide a habitat and protection for the fish. Fish pens may be used for freshwater or for saltwater aquaculture.
Some conventional fish farming systems provide a pen that is anchored to the ocean floor. In one embodiment, a fish pen includes four spar buoys with damper plates coupled to the bottom that dampen the buoy motion caused by wave action. The four spar buoys are typically arranged in a rectangular array with a net fastened to the spar buoys to define a box-like enclosure. Anchor lines extend outwardly and downwardly from each spar buoy to support the nets.
More recent innovations in fish pens employing a center spar buoy or center cluster of spar buoys are disclosed in U.S. Pat. No. 5,359,962, to Loverich, and in U.S. Pat. No. 5,617,813, to Loverich et al., both of which are hereby incorporated by reference in their entireties. Loverich et al. discloses a mobile pen for raising fish or shellfish having an elongate central vertical spar buoy surrounded by at least one net-supporting rim assembly with continuous netting extending from an upper end of the spar buoy to the rim assembly and thence to a lower, submerged end of the spar buoy. For example, a novel open sea center spar fish pen having an elongate spar buoy, and one or more rim assemblies attached to the spar buoy is disclosed in U.S. Pat. No. 9,072,282, to Madsen et al., which is hereby incorporated by reference in its entirety.
A submerged feed disperser system for an open sea fish pen is disclosed herein that increases the effective volume over which feed is delivered inside a fish pen in a submerged state. The feed disperser allows more fish to eat to satiation by reducing competition for feed. The reduced competition for feed encourages consistent fish growth within a population, while reducing aggression during feeding, and reducing the loss or waste of feed pellets during feeding. The feed disperser has also been found to produce an improved coefficient of variation in fish size by allowing less aggressive fish to more easily acquire and consume feed, decreasing fish mortality and improving the feed conversion ratio. The feed disperser has been found to reduce damage to pelletized fish feed during dispersal of the feed.
Less efficient alternate means for distributing feed within fish pens currently in use employ a small concentrated feed outflow point, typically using a structure with four distribution points arranged in a row and spread over a relatively short distance, for example one meter. In these prior art systems feed is delivered over a small area resulting in intense competition for feed and a highly skewed distribution of feed consumption towards larger, more aggressive fish.
Other fish feed systems are known in the art. U.S. Pat. No. 7,743,733, to Harrison et al., which is hereby incorporated by reference in its entirety, discloses an offshore aquaculture system including a fish feeding apparatus configured to dispense a slurry containing fish feed in streams upwardly and outwardly from a dispenser head at a number of circumferentially spaced outlets at the water surface.
U.S. Pat. No. 9,655,347, to Troy et al., which is hereby incorporated by reference in its entirety, discloses an open ocean fish farm structure including a feeding system that distributes fish feed through a plurality of individual feeder hoses, each hose extending from a feed storage bin to a point on the upper aspect of the surface of the fish enclosure.
U.S. Pat. No. 9,326,493, to Han et al., which is hereby incorporated by reference in its entirety, discloses an automatic feeding system for an underwater farm with a single feeding hose that is connected to a mixing tank containing the fish feed, and extends to the underwater fish farm.
These prior art fish feeding systems do not disperse fish feed throughout the fish enclosure in a manner that discourages competition for food, and encourages a more equitable distribution of food to provide more optimal and consistent feeding.

Submerged feed disperser for aquaculture system


This invention provides for novel human antibodies that specifically bind to c-erbB-2. The antibodies may be used alone or as components of chimeric molecules that specifically target and deliver effector molecules to cells overexpressing c-erbB-2.

This invention pertains to the fields of immunodiagnostics and immunotherapeutics. In particular, this invention pertains to the discovery of novel human antibodies that specifically bind to c-erbB-2, and to chimeric molecules containing these antibodies.
Conventional cancer chemotherapeutic agents cannot distinguish between normal cells and tumor cells and hence damage and kill normal proliferating tissues. One approach to reduce this toxic side effect is to specifically target the chemotherapeutic agent to the tumor. This is the rationale behind the development of immunotoxins, chimeric molecules composed of an antibody either chemically conjugated or fused to a toxin that binds specifically to antigens on the surface of a tumor cell thereby killing or inhibiting the growth of the cell (Frankel et al. Ann. Rev. Med., 37: 127 (1986)). The majority of immunotoxins prepared to date, have been made using murine monoclonal antibodies (Mabs) that exhibit specificity for tumor cells. Immunotoxins made from Mabs demonstrate relatively selective killing of tumor cells in vitro and tumor regression in animal models (Id.).
Despite these promising results, the use of immunotoxins in humans has been limited by toxicity, immunogenicity and a failure to identify highly specific tumor antigens (Byers et al. Cancer Res., 49: 6153). Nonspecific toxicity results from the failure of the monoclonal antibody to bind specifically and with high affinity to tumor cells. As a result, nonspecific cell killing occurs. In addition, the foreign immunotoxin molecule elicits a strong immune response in humans. The immunogenicity of the toxin portion of the immunotoxin has recently been overcome by using the human analog of RNase (Rybak et al. Proc. Nat. Acad. Sci., USA, 89: 3165 (1992)). The murine antibody portion, however, is still significantly immunogenic (Sawler et al., J. Immunol., 135: 1530 (1985)).
Immunogenicity could be avoided and toxicity reduced if high affinity tumor specific human antibodies were available. However, the production of human monoclonal antibodies using conventional hybridoma technology has proven extremely difficult (James et al., J. Immunol. Meth., 100: 5 (1987)). Furthermore, the paucity of purified tumor-specific antigens makes it necessary to immunize with intact tumor cells or partially purified antigen. Most of the antibodies produced react with antigens which are also common to normal cells and are therefore unsuitable for use as tumor-specific targeting molecules.

High affinity human antibodies to tumor antigens

The Regents of the University of California


A secondary seat belt warning system for a motor vehicle includes at least one control module for activating at least one secondary warning signal. The secondary seat belt warning system also includes a driver seat belt sensor for producing an input signal indicative of a state of a driver seat belt between a buckled and unbuckled condition. The secondary seat belt warning system includes at least one passenger seat belt sensor for producing an input signal indicative of a state of at least one passenger seat belt between a buckled and unbuckled condition. The at least one control module communicates with the driver seat belt sensor and the at least one passenger seat belt sensor for activating the at least one secondary warning signal to alert a corresponding occupant of the motor vehicle if the state of at least one of the driver seat belt and the at least one passenger seat belt is the unbuckled condition.

1. Field of the Invention
The present invention relates generally to seat belt warning systems for vehicles and, more specifically, to a secondary seat belt warning system for a motor vehicle.
2. Description of the Related Art
It is known that motor vehicles such as automotive vehicles often include seat belt warning systems for reminding an occupant of the vehicle that their seat belt is unbuckled. Typically, when the vehicle ignition is turned to a xe2x80x9crunxe2x80x9d or xe2x80x9conxe2x80x9d position, an audible chime and visible warning light will turn on for a predetermined amount of time to alert, or remind, the occupant to buckle or fasten their seat belt. If their seat belt is already buckled, neither the chime nor the light will turn on. The audible chime will typically only sound for a few seconds and the visible warning light will typically flash for a short period of time or remain illuminated for approximately ten to sixty seconds. After these relatively short time durations have expired, the warnings will turn off and remain off, regardless of whether the seat belt is buckled or unbuckled, until the initial ignition xe2x80x9crunxe2x80x9d position is reactivated.
An example of a seat belt usage indicating system is disclosed in U.S. Pat. No. 5,483,221 to Mutter et al. In this patent, seat belts in a motor vehicle are monitored, and a reminder is initiated in response to a belt or restraint sensor indicating an engaged or nonengaged state of a seat belt or restraint, a vehicle sensor indicating when the vehicle is in use, an annunciator controllably producing a reminder, and an electronic control controlling the annunciator. The reminder is produced when the seat restraint is in a nonengaged state after having been in an engaged state while the vehicle is in use.
It is also known to provide a secondary seat belt warning system for a motor vehicle. An example of such a system in disclosed in copending application Serial No. 09/448,352, filed Jan. 20, 2000, entitled xe2x80x9cSECONDARY SEAT BELT WARNING SYSTEMxe2x80x9d. In this application, a secondary seat belt warning system includes a control module for activating at least one output warning signal in response to receiving a plurality of predetermined control feedback input signals. The secondary seat belt warning system includes an ignition switch connected to the control module for producing an input signal to the control module indicative of a state of a vehicle ignition between an xe2x80x9coffxe2x80x9d position and an xe2x80x9conxe2x80x9d position. The secondary seat belt warning system also includes a seat belt sensor connected to the control module for producing an input signal to the control module indicative of a state of the seat belt between a buckled and unbuckled condition. The secondary seat belt warning system further includes a vehicle speed sensor connected to the control module for producing an input signal to the control module in response to the vehicle speed sensor measuring a predetermined threshold speed of the vehicle. Finally, the secondary seat belt warning system includes a seat belt indicator system connected to the control module for producing an output signal in response to the control module receiving an input signal from the seat belt sensor in the unbuckled condition and an input signal from the vehicle speed sensor above the predetermined threshold, whereby the output signal triggers at least one of an audible and visible indicator to alert the occupant of the vehicle of the unbuckled condition of the seat belt.
Although the current secondary seat belt warning system reminds the occupant to buckle their seat belt in addition to the primary warning, these secondary warnings are a xe2x80x9conce per drive cyclexe2x80x9d event typically at the start-of each trip (key cycle), and this limitation exists due to the inability to determine a seat belt user or a seat belt nonuser. Another disadvantage is that the secondary seat belt warning system does not allow the occupant to change its declaration as a seat belt user or non-user without the engine being turned off. Another disadvantage is that the secondary seat belt warning system is available only once in a drive cycle.
It is desirable to provide a secondary seat belt warning system that identifies a vehicle occupant as a seat belt user or a non-user. It is also desirable to provide a secondary seat belt warning system that combines occupant seat occupancy detection and occupant belt use monitoring to add occupant passenger seat belt reminder warnings. It is further desirable to provide a secondary seat belt warning system with repeatable warnings to warn occupants throughout the duration of a drive cycle or trip. Therefore, there is a need in the art to provide a secondary seat belt warning system that meets these desires.
Accordingly, the present invention is a secondary seat belt warning system for a. motor vehicle including at least one control module for activating at least one secondary warning signal. The secondary seat belt warning system also includes a driver seat belt sensor. for producing an input signal indicative of a state of a driver seat belt between a buckled and unbuckled condition. The secondary seat belt warning system includes at least one passenger seat belt sensor for producing an input signal indicative of a state of at least one passenger seat belt between a buckled and unbuckled condition. The at least one control module communicates with the driver seat belt sensor and the at least one passenger seat belt sensor for activating the at least one secondary warning signal to alert a corresponding occupant of the motor vehicle if the state of at least one of the driver seat belt and the at least one passenger seat belt is the unbuckled condition.
One advantage of the present invention is that a secondary seat belt warning system is provided for a motor vehicle. Another advantage of the present invention is that the secondary seat belt warning system monitors the seat belt use status of a vehicle occupant to dynamically determine if the occupant is a seat belt user or a seat belt non-user. Yet another advantage of the present invention is that a method is provided for monitoring an occupant""s seat belt and to assign them as a seat belt user or non-user and to change the assignment at any time during a drive cycle such that secondary warnings can be provided to seat belt xe2x80x9cusersxe2x80x9d at any time during a drive cycle, while not providing secondary warnings to seat belt xe2x80x9cnon-usersxe2x80x9d. Still another advantage of the present invention is that the secondary seat belt warning system provides secondary warnings whenever an occupant seat belt is unbuckled independent of when in the drive cycle it is unbuckled. A further advantage of the present invention is that the secondary seat belt warning system includes a combined driver and passenger occupant reminder feature which subtly reminds the driver and front passenger seat occupant to buckle their seat belts, in the event that they have forgotten to buckle-up at the beginning of a drive cycle. Yet a further another advantage of the present invention is that the secondary seat belt warning system includes a repeatable secondary warning feature which subtly reminds the driver and front passenger seat occupant to buckle their seat belts in the event that they have forgotten to buckle-up at any point during an extended trip or drive cycle.


The embodiments of the present invention relate generally to the fabrication of integrated circuits, and more particularly to a structure and method for fabricating a pair of ultra-thin metal wires in an opening using a selective deposition process.

Integrated circuit (IC) chips typically include multiple levels of conductive features which are vertically spaced apart and separated by intermediate insulating layers. Interconnections are formed between the levels of conductive features in the chip to provide high wiring density and good thermal performance. The interconnections are formed using lines and vias, which are etched through the insulating layers separating the levels conductive features of the device. The lines and vias are then filled with a conductive material to form interconnect structures (i.e., wires). Typically, a conductive metal, such as copper is used to form the interconnect structures.
Interconnects are commonly formed through a photolithography process that includes the deposition of a patternable masking layer commonly known as photoresist. One preferred photolithographic method of making interconnect structures is the damascene process. A typical damascene process includes: a blanket deposition of a dielectric material; patterning of the dielectric material using photoresist to form openings; deposition of a conductive material onto the substrate in sufficient thickness to fill the openings; and removal of the excessive conductive material from the substrate surface using a chemical reactant-based process, mechanical methods, or a combined chemical mechanical polishing (CMP) techniques.

Ultra-thin metal wires formed through selective deposition