An amplifier includes a differential amplifier (10) having an input stage (20) for amplifying a differential input signal (Vin), and an output stage (6) coupled to the input stage (20) for producing and output signal (Vout). The input stage (20) includes main input circuitry (20A) for amplifying small-signal values of the input signal (Vin) and alternative input circuitry (20B) for amplifying the input signal (Vin) during conditions which cause thermal imbalance in the main input circuitry (20B). The input stage (20) includes switching circuitry (12) for coupling the input signal (Vin) to the main input circuitry (20A) during normal small-signal operating conditions and to the alternative input circuitry (20A) during large-signal operating conditions that cause thermal imbalance in the main input circuitry (20B).

The present invention relates generally to problems associated with differential thermal effects caused by steady-state or transient power imbalances in integrated circuit chips, and particularly to circuits and techniques for reducing the time required for recovery from such differential thermal effects.
It is well known that transient or steady-state large-signal input conditions can cause circuit operation that creates large power imbalances within an integrated circuit. In some cases, the integrated circuit must be operated so as to allow it sufficient time to "recover" from the large power imbalances before proper circuit operation can continue. The power imbalances can cause a temporary temperature imbalance that substantially changes the operating characteristics of circuit components such as transistors located in the region of the temperature imbalance. This may result in unacceptably inaccurate circuit performance until enough "recovery time" has elapsed to allow the temperature to be balanced within the region.
Various other conditions are known to cause similar imbalanced thermal conditions in integrated circuit chips. For example, large-signal slewing conditions or transient imbalances may cause recovery settling "tails" in the output response of a circuit. Input signal overdrive conditions beyond the linear range of an amplifier and its feedback loop may result in thermal imbalance conditions of long duration. Also, various special-purpose applications that cause linear feedback in an amplifier circuit to be interrupted or limited (e.g. in sample/hold amplifiers, peak detector circuits, and limiting/clamping amplifiers), can cause thermal imbalance conditions of the kind referred to above in. Although a thermal imbalance condition can occur due to simple transient slewing, it may be most problematic in applications in which a feedback loop is interrupted for a relatively long interval, for example in a sample/hold amplifier, a peak detector circuit, a limiting or clamping amplifier, or a multiplexed amplifier.
FIG. 1 shows a conventional closed loop feedback network that includes an operational amplifier 1 which receives a differential input signal Vin applied between a (−) input conductor 3 and a (+) input conductor 4. The input conductors 3 and 4 are connected to the inputs of a differential input transistor pair in circuitry 2A of an input stage 2 of amplifier 1. Input stage 2 typically also includes a folded cascode circuit, the output of which drives the high impedance compensation node 5 (i.e., "comp" node 5 of folded cascode stage 2A is connected to the input of a conventional output driver circuit 6A of an output stage 6. Output driver circuit 6A produces an output signal Vout on conductor 7, which is connected to the input of a feedback network 8 (which often is simply a feedback resistor). The output of feedback network 8 is connected to inverting input 3. FIG. 2 shows a schematic diagram of a conventional differential input circuit and folded cascode stage which can be used as input stage 2 of FIG. 1.
Referring to FIG. 2, Vin− is applied to the base of an NPN input transistor Q1, and Vin+ is applied to the base of an NPN input transistor Q2, the emitter of which is coupled by conductor 27 to the collector of an NPN current source transistor Q12. The emitter of transistor Q12 is coupled by a resistor R3 to a power supply voltage VEE. The emitter of input transistor Q1 is connected by conductor 26 to the collector of a current source transistor Q11, the emitter of which is coupled by a resistor R2 to VEE. A resistor R1 is connected between conductors 26 and 27. The bases of current source transistors Q11 and Q12 are connected to a bias voltage VB1 on conductor 22. The collector of input transistor Q1 is coupled by a conductor 24 to the emitter of a folded cascode PNP transistor Q6 and to one terminal of a resistor R5 coupled between conductor 24 and a power supply voltage VCC. Similarly, the collector of input transistor Q2 is coupled by a conductor 25 to the emitter of a folded cascode PNP transistor Q5 and to one terminal of a resistor R4 coupled between conductor 24 and VCC. The bases of cascode transistors Q5 and Q6 are connected to a bias voltage VB2 by conductor 28. Typically, the high impedance compensation or "comp" node of the entire circuit 2 is the collector of transistor Q6. In FIG. 2, the collector of transistor Q5 is coupled to an output of a current mirror 30. The collector of transistor Q6 is connected by conductor 5 to an input of current mirror 30. The voltage on conductor 5 is labeled Vcomp.
In the conventional closed loop feedback network of FIG. 1, the differential input error voltage is forced by the feedback loop to be nearly zero. Therefore, input stage 2 is driven to a balanced condition. Typical symmetrical construction of such circuitry on the integrated circuit chip and, along with the balanced operating condition due to the nearly-zero error voltage value of Vin, result in a thermally balanced condition of each of the power-dissipating circuit elements with respect to corresponding balanced components on the other side of the symmetrical construction.
However, if the differential input voltage Vin between the bases of transistors Q1 and Q2 is excessively large, then one of transistors Q1 and Q2 carries much more current than the other, and therefore dissipates much more than the normal amount of power and, therefore increases the temperature of that transistor. Computer analysis and laboratory measurements have shown that the increased temperature can result in significant thermally-induced offset voltages in transistors Q1, Q2, Q5 and Q6. The effect of this on the output voltage Vout (FIG. 1) appears as a delay in the waveform "A" shown in FIG. 6.
For example, if Vin+ is much larger than Vin−, then input transistor Q1 is turned off and dissipates no power, and a large current flows through input transistor Q2, causing it to dissipate a large amount of power. This results in substantially higher temperature in input transistor Q2 than in input transistor Q1, which can substantially change the operating characteristic of transistor Q2 relative to transistor Q1. After the above described Vin input "overdrive" condition ends, the feedback loop causes Vin=Vin+−Vin− to be essentially zero so the feedback loop is properly balanced, and an amount of time (i.e., the thermal recovery time or "tail") is required for the temperature of input transistor Q2 to recover to the temperature of input transistor Q1 so that the thermally sensitive circuitry including transistors Q1 and Q2 is balanced and the thermally-induced input offset voltage settles to a negligible value. Only then can a reliable precise value of Vout be obtained from the feedback amplifier. However, the thermal recovery time or "tail" shown in waveform "A" of FIG. 6 may be unacceptably long. Also, during the Vin overdrive condition the same current flowing through transistor Q2 is subtracted from the current flowing through cascode transistor Q5, which reduces the power dissipation in transistor Q5. This causes a thermal imbalance between cascode transistors Q5 and Q6.
Prior techniques are known for switching the amplifier signal path back and forth between separate differential input stages of a single operational amplifier. For example, the assignee's line of SWOP AMP operational amplifiers ("switchable op amps") uses this technique. However, the switching of the differential input stages therein is performed in response to a timed external signal, such as a clock signal or a control signal.
There appears to be no previously known practical solution to reducing the above described long thermal recovery "tails".
Thus, there is an unmet need for a circuit and technique for reducing or preventing transient or temporary power imbalances in an integrated circuit amplifier which cause transient inaccuracies in an output signal produced by the amplifier.
There also is an unmet need for a circuit and technique for reducing or preventing a transient or temporary power imbalance in a particular region of an integrated circuit amplifier which causes a thermal tail of a signal produced by the amplifier.
There also is an unmet need for a circuit and technique for reducing or preventing a transient or temporary power imbalance in a particular region of an integrated circuit amplifier due to an excessively large input signal.
There also is an unmet need for a circuit and technique for reducing or preventing a transient or temporary power imbalance in a particular region of an integrated circuit amplifier due to an interruption in a feedback loop in the amplifier.
There also is an unmet need for a circuit and technique for reducing or preventing a transient or temporary power imbalance in regions of both a differential input circuit amplifier and a folded cascode circuit in an integrated circuit due to an excessively large input signal.
There also is an unmet need for a circuit and technique for electrically detecting signal conditions which would cause transient or temporary thermal imbalances in an integrated circuit without relying on system timing or control signals.

Differential amplifier circuit and method for reducing thermally induced offsets caused by large differential signals


Polyamide-based resin expanded beads having a crystallite size of more than 8 nm as measured by X-ray diffraction method are provided.

A polyamide-based resin is known as a resin having high heat resistance, excellent in abrasion resistance and chemical resistance. An expanded molded body made by causing the polyamide-based resin to expand achieves weight saving while maintaining the excellent properties, so that use for automobile parts and the like can be expected. Accordingly, various studies on an expanded molded body of polyamide-based resin have been performed for implementation in various applications. For example, in Patent Literature 1, for the purpose of improving heat resistance and sound insulation, a polyamide-based resin expanded beads molded body having a crystallite size of 10 nm or more and a crystallinity of 10 to 50%, produced by a process including filling a mold cavity with polyamide-based resin pre-expanding beads and raising the temperature using steam in a multi-step wise manner, is disclosed.


An electromagnetic pickup for electric guitars has one or two dual-coil assemblies wherein an inner coil is wound around a bobbin and then an outer coil around the inner coil. In the dual-coil assembly the inner coil replaces the entire or part of wall space of pole piece holes in a plastic molded bobbin. The outer and inner coils in the dual-coil assembly are electrically connected in-phase to produce single coil pickup sound. The outer coil or the serially connected inner and outer coils are connected to a coil in the other pole piece/bobbin/coil assembly out-of-phase to generate humbucking pickup sound.

An electromagnetic pickup (pickup, hereinafter) converts the vibrations of plucked strings of an electric guitar, which are located on top of the pickup where electromagnetic fields are formed, into an electrical signal. In general a single coil pickup (SC pickup, hereinafter) comprises of a set of pole pieces made of magnetic or ferromagnetic materials, magnetic wire coil, bobbin plates, and lead wires. The SC pickup is sensitive to external magnetic fields created by speakers, power transducers, fluorescent light sources and so on, resulting in undesired humming noise.
Such humming noise can be reduced or eliminated by combining two magnetic sensing coils electrically out-of-phase so that two signals generated by the external sources can be cancelled each other. The electromagnetic signal from guitar strings can be preserved either by setting the two coils magnetically out-of-phase or by isolating one of the two coils magnetically from the strings.
Overall, there are two structural configurations—1) side-by-side configuration, wherein two coils are situated side-by-side and are both electrically and magnetically out-of-phase (U.S. Pat. No. 2,896,491, U.S. Pat. No. 4,364,295, U.S. Pat. No. 4,372,186, U.S. Pat. No. 4,501,185, U.S. Pat. No. 5,111,728, U.S. Pat. No. 5,525,750, U.S. Pat. No. 5,530,199, U.S. Pat. No. 8,309,836, US Pat. Appl. No. US 2012/0103170, and so on), and 2) stacked configuration, wherein two coils are stacked on top of each other and are both electrically and magnetically out-of-phase like the former (U.S. Pat. No. 6,846,981), or electrically out-of-phase and magnetically in-phase with magnetic isolating means for one coil (U.S. Pat. No. 4,442,749, U.S. Pat. No. 5,168,117, U.S. Pat. No. 5,668,520, U.S. Pat. No. 5,811,710, U.S. Pat. No. 6,103,966, U.S. Pat. No. 6,291,758, U.S. Pat. No. 6,291,759, U.S. Pat. No. 6,846,981, U.S. Pat. No. 7,166,793, U.S. Pat. No. 7,189,916, and so on).
The most popular hum-cancelling pickup with the side-by-side configuration was introduced by Lover (U.S. Pat. No. 2,896,491). The pickups built according to this invention have been called PAF (Patent Applied For), which was printed on the bottom plate of those pickups in the early days. In this document the hum-cancelling pickup with the side-by-side configuration is referred to simply as the HB (Hum-Bucking) pickup, hereinafter. It is to be noted that the hum-cancelling pickup with the stacked configuration will be referred to as the stacked hum-cancelling pickup.
A pickup has a unique response characteristic to string vibrations resulting in a unique tone color. Pickup tone is dependent on many parameters, which include magnet materials, pole pieces, bobbin materials and structures, magnet wire gage, magnet wire coating materials, the number of wire turns and so on. Although external factors such as guitar builds, effects pedals and amplifiers can color the tone characters to some extent, they cannot completely override the original tone of the pickup. That is why old classical pickups including the said PAF are still popular, and also, a number of different pickup products are available in the music industry.
Two most distinctive tone colors are generated from aforementioned SC and HB pickups. The SC pickup usually produces a clear and bright sound with a focus on the treble to mid-range domain, whereas the HB pickup produces a warm and thick sound with a focus on the mid-range domain. The majority of electric guitar players use both types of pickups depending on the needs. Because it is inconvenient and impractical to change guitars for different pickup sounds in the middle of performance, many guitar builders and pickup makers offer the option of "coil-splitting", by which a guitar player can use only one of the two coils in the HB pickup, or more rarely "combining", in which two individual SC pickups are electrically connected like one HB pickup. However, both methods do not deliver a purposed SC or HB sound very well. A coil-split pickup sound is typically thinner and less lively than a genuine SC pickup sound. On the other hand, a combination of two genuine SC pickups does not usually produce a good HB pickup sound defined by warmth and fullness. As a result, pickups that can produce both HB and SC sounds are hardly found.
From a set of experiments it was found that one of the most critical factors, which make the difference in sound characteristics between a genuine SC pickup and a coil-split HB pickup, was the space between the coil and the pole pieces and that such space in the HB pickup can be made closer to that of the SC pickup without damaging or changing the sound characteristics and form factor of the HB pickup. The details of this invention and embodiments are described in the next sections.

Electromagnetic pickup for stringed instruments


An isotropic or partially isotropic etch shrinks lithographically patterned photoresist (211, 212) to yield reduced linewidth patterned photoresist (213, 214) with a buried antireflective coating also acting as an etchstop or a sacrificial layer. The reduced linewidth pattern (213, 214) provide an etch mask for subsequent anisotropic etching of underlying material such as polysilicon (206) or metal or insulator or ferroelectric.

The invention relates to electronic semiconductor devices, and, more particularly, to fabrication methods for such devices.
Semiconductor integrated circuits with high device density require minimum size structures such as short gates for field effect transistors (FETs), small area emitters for bipolar transistors, and narrow interconnection lines between devices. The formation of such polysilicon or metal structures typically involves definition of the locations of such structures in a layer of photoresist on a layer of polysilicon or metal by exposure of the photoresist with light passing through a reticle containing the desired structure pattern. After exposure and development of the photoresist, the underlying layer of polysilicon or metal is anisotropically etched using the patterned photoresist as the etch mask. Thus the minimum polysilicon or metal linewidth equals the minimum linewidth that can be developed in the photoresist. Current optical steppers expose the photoresist using light of wavelength 365 nm (called I-line after the corresonding emission line in a high-pressure mercury arc lamp used to generate the light), and pattern linewidths in photoresist of less than about 0.30 .mu.m with a standard deviation of less than about 0.01 .mu.m cannot be satisfactorily generated with I-line lithography.
FIGS. 1a-c illustrate a known method to create sublithographic polysilicon gate structures and includes minimal geometry patterning photoresist on a polysilicon layer (FIG. 1a), isotropically etching the photoresist to reduce linewidth (FIG. 1b), and anisotropically etching the polysilicon with the reduced linewidth photoresist as etch mask (FIG. 1c). This approach has problems including contamination of the polysilicon.
The use of a photoresist mask for anisotropic etching polysilicon gates can leave residual ridges of hardened photoresist on the edges of the polysilicon gates after the etch. Plasma etch species harden the photoresist sidewalls during the polysilicon etch, and the subsequent oxygen plasma photoresist strip may not fully remove the ridges; FIG. 1d. Also, separate wet etches to strip the ridges may be used but lack robustness with respect to modifications. Any ridge residue will carbonize during later heat treatments and impede formation of titanium disilicide (TiSi.sub.2) in a self-aligned gate siliication process. Thus simple and complete removal of photoresist residue is a problem.


A high-voltage discharge lamp lighting device provides a starting pulse voltage sufficient to turn on a high-voltage discharge lamp having terminal wire connections of variable length. A power conversion circuit is coupled to a commercial AC power source input and rectifies the AC input into a predetermined DC voltage output. A charging capacitor is coupled to the power conversion circuit. A full bridge circuit is coupled to the power conversion circuit and the charging capacitor and provides a rectangular wave AC output signal to a transformer primary winding circuit of at least a capacitor, a single switching element and a primary winding of a transformer. A low pulse voltage is induced in the primary winding and a transformer secondary winding is connected on one end to the high-voltage discharge lamp, wherein the low pulse voltage is stepped up to a high pulse voltage and applied to the high-voltage discharge lamp. A reference voltage is generated in a reference transformer winding representative of the high pulse voltage. A starting pulse equivalent value detection circuit is connected to the reference winding and detects a value associated with the reference voltage. A control circuit receives said value from said detection circuit, and variably controls at least one of a frequency of the single switching element or an ON impedance of the single switching element in association with said value, wherein said frequency or ON impedance is further associated with a starting pulse voltage sufficient to start the high-voltage discharge lamp.

The present invention relates to a high-voltage discharge lamp lighting device equipped with means adapted to adjust a peak value of a high-pressure pulse voltage at the time of start. The present invention further relates to a lighting fixture using the device.
A high-voltage discharge lamp is compact, yet can produce powerful beams of light, is near a point light source and is easily controlled in light distribution. For these reasons, the high-voltage discharge lamp has recently become a favorable alternative to incandescent and halogen lamps. A high-pressure pulse voltage of a few kV is generally required to start the high-voltage discharge lamp.
FIG. 14 shows a typical example of circuit structure for such a lamp. Reference character E denotes a DC power source, reference numeral 4 denotes a step-down chopper circuit, reference numeral 6 denotes a polarity reversal circuit, reference numeral 7 denotes a starting pulse generation circuit and reference character T1 is a high-voltage pulse transformer. The step-down chopper circuit 4 is formed of a switching element Q2, a diode D2, an inductor L3 and a smoothing capacitor C4. The configuration and operation of these components are generally known in the art and further description thereof is omitted. The polarity reversal circuit 6 is formed of a full-bridge circuit including switching elements Q3 to Q6 and applies a rectangular wave having a frequency of from a few dozen to a few hundred Hz to the starting pulse generation circuit 7 and the high-voltage discharge lamp 8.
The starting pulse generation circuit 7 has the transformer T1 including a secondary winding N2 serially connected to the high-voltage discharge lamp 8, a capacitor C1 for passing a pulse current to a primary winding N1, a charge resistor Rc and a switching element Q7 for discharging the capacitor C1.
The pulse generation operation is well known. For example, when the switching elements Q3 and Q6 of the polarity reversal circuit 6 are turned on and the switching elements Q4 and Q5 are turned off, a charge current flows from the capacitor C4 to the capacitor C1 via the switching element Q3, the primary winding N1 of the transformer T1, the charge resistor Rc, the capacitor C1 and the switching element Q6 to charge the capacitor C1 so that the switching element Q7 becomes positive. After that, when the switching elements Q3 and Q6 of the polarity reversal circuit 6 are turned off and the switching elements Q4 and Q5 are turned on, a high voltage obtained by adding the voltage of the capacitor C4 to the voltage of the capacitor C1 is applied to the switching element Q7 and exceeds a breakover voltage of the switching element Q7. As a result, an electric charge of the capacitor C1 is steeply discharged via the switching element Q7 and the steep discharge current flows into the primary winding N1 of the high-voltage pulse transformer T1, generating a pulse voltage. A high-pressure pulse voltage obtained by boosting the pulse voltage by the transformer T1 occurs in the secondary winding N2 to cause dielectric breakdown of the high-voltage discharge lamp 8. Generally, in the high-voltage discharge lamp 8, the starting pulse voltage is defined as 3-5 kV.
In the high-voltage discharge lamp lighting device, when the output wiring length (lamp terminal wire length) is increased, output capacitance increases and the starting pulse voltage is attenuated. This causes a problem that the starting pulse voltage of the lamp falls below a defined value and thus the lamp cannot be started. To prevent this problem. the high-voltage discharge lamp lighting device needs to be able to output 3-5 kV even when the output wiring length is relatively long. In this case, however, when the output wiring length is short, the pulse voltage becomes 5 kV or more, resulting in a possibility of leakage in the wiring or socket.
Japanese Unexamined Patent Publication No. 2007-52977 describes a previous attempt to address this problem. FIG. 15 shows the circuit structure of this particular example. A starting pulse generation circuit operates at the start-up of the high-voltage discharge lamp 8 and generates a high-pressure pulse voltage. The starting pulse generation circuit has a transformer T1, a switching element Q7 which can be turned on/off according to an external control signal, a capacitor C1 and an inductor L1 for over-current protection of the switching element Q7. This document proposes that a tertiary winding N3 of the transformer T1, a voltage divider circuit 11 and a pulse detection circuit 12 detect a peak value of the high-pressure pulse voltage and feed back the detection value so that a control circuit 9 may maintain the starting high voltage within a predetermined value.
However, the starting high voltage must be lowered to a voltage desired for feedback and a circuit structure such as a voltage divider circuit is required to lower the starting high voltage, leading to an increase in size and costs of the lighting device. This method is disadvantageous in part because the peak value of the starting high voltage cannot be accurately detected due to error factors such as an inherent variation in components of the voltage divider circuit and temperature characteristics. Further, since the peak value of the starting high voltage varies in generation timing, it is difficult to detect the accurate peak value depending on detection timing.

High voltage discharge lamp lighting device


Methods for the preparation of bio-based malonic acid and diester derivatives of malonic acid are provided. For example, a dialkyl malonate may be prepared by the steps of (i) separating calcium malonate crystals from a fermentation broth; (ii) obtaining dissolved malonic acid; (iii) crystallizing the dissolved malonic acid; and (iv) performing esterification to obtain the dialkyl malonate. The disclosed methods produce diester derivatives of malonic acid with fewer impurities, which is useful for many industrial processes. The diester derivatives of malonic acid can be purified from existing sources of malonic acid, or from malonic acid made from a renewable carbon source.

The long-term economic and environmental concerns associated with the petrochemical industry have provided impetus for increased research, development, and commercialization of processes that derive industrial and consumer chemicals not from petroleum feedstocks but rather from renewable feedstocks. One approach is the development of biorefining processes to convert renewable feedstocks into products that can replace petroleum-derived chemicals. Two common goals in improving a biorefining process include achieving a lower cost of production and reducing carbon dioxide emissions.
One such presently petroleum-derived chemical is malonic acid (propanedioic acid, CAS No. 141-82-2). Propanedioic acid ("malonate", CAS No. 141-82-2) is currently produced from non-renewable, petroleum feedstocks. Mono- or di-esterification of one or both carboxylic acid moieties of malonate with an alcohol (e.g. methanol or ethanol) yields the monoalkyl and dialkyl malonates, respectively. 2,2-dimethyl-1,3-dioxane-4,6-dione ("Meldrum's acid" CAS No. 2033-24-1) is produced from malonate using either acetone in acetic anhydride or isopropenyl acetate in acid. Malonic acid and chemical derivatives of malonic acid (such as, for example, monoalkyl malonate, dialkyl malonate, and 2,2-dimethyl-1,3-dioxane-4,6-dione are used for the production of many industrial and consumer products, including polyesters, protective coatings, solvents, electronic products, flavors, fragrances, pharmaceuticals, surgical adhesives, and food additives.
Another group of petroleum-derived chemicals are diester derivatives of malonic acid, including diethyl malonate and dimethyl malonate. Diethyl malonate ("DEM", Malonic acid diethyl ester, CAS No. 105-53-3) and dimethyl malonate ("DMM", Malonic acid dimethyl ester, CAS No. 108-59-8) are currently produced from non-renewable, petroleum feedstocks. Malonic acid has two carboxyl groups close together. To form diethyl malonate or dimethyl malonate from malonic acid, the hydroxyl group on each of two malonic acid carboxyl groups is replaced by an ethoxy group. Diester derivatives of malonic acid are used for the production of many industrial and consumer products, including barbituates, artificial flavorings, vitamins (including B1 and B6), polyesters, protective coatings, solvents, resins, polymers, electronic products, fragrances, pharmaceuticals, surgical adhesives, and food additives. Chemical synthesis has traditionally been the preferred route for synthesis of malonic acid, diester derivatives of malonic acid, malonate and malonate-derived compounds. For example, dialkyl malonates are produced through either a hydrogen cyanide or carbon monoxide process. In the hydrogen cyanide process, sodium cyanide is reacted with sodium chloroacetate at elevated temperatures to produce sodium cyanoacetate, which is subsequently reacted with an alcohol/mineral acid mixture to produce the dialkyl malonate. Strittmatter et al. report yields of 75-85% (see "Malonic acid and Derivatives" in: Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, New York (2002)). In the carbon monoxide process, dialkyl malonates (also referred to herein as diester malonates) are produced through cobalt-catalyzed alkoxycarbonylation of chloroacetates with carbon monoxide in the presence of an alcohol at elevated temperatures and pressures. By way of further example, diester derivatives of malonic acid can be produced through a chloroacetic acid/sodium cyanide process followed by Fischer esterification.
Malonic acid, its esters, and methylene malonates provide an opportunity to create an entirely new reactive materials platform capable of addressing limitations in current epoxy, urethane, unsaturated polyester, and acrylic systems. Petrochemical-based materials often require trade-offs to deliver desired end properties. Such limitations can include energy intensive curing, high VOC emissions due to solvent usage, and chemical leaching from consumer products (for example, bisphenol-A). However, the existing, petrochemical-based production routes to the malonate and malonate-derived compounds are low yielding, environmentally damaging, dependent upon non-renewable feedstocks, and require expensive treatment of wastewater and exhaust gas. Furthermore, the cost and other intrinsic problems with incumbent petrochemical manufacturing have limited the adoption of malonates. Global capacity is exclusive to China using a low-yielding process based on toxic sodium cyanide and monochloroacetic acid (MCAA). Due to their high cost and environmental footprint, malonates are currently only used in niche pharmaceutical production, flavor and fragrance formulations, agricultural chemicals, and electronics with unmet potential as a major new materials platform. In addition to cost and raw materials problems, limited global MCAA capacity (about 200 kilotons per annum) also stymies further industry adoption. property In addition to cost and a more robust supply chain, purity is a factor to consider, particularly for reactive resin and polymer systems. Petrochemical malonates are plagued by difficult to remove chlorinated intermediates and cyanoacetate impurities, interfering with polymerization.
Additionally, the existing, petrochemical-based production routes to yield diester derivatives of malonic acid can result in preparations containing impurities that affect many downstream properties, including cure speed and hardness of resins and polymers. Further, these methods depend upon sourcing malonic acid from non-renewable feedstocks and require expensive treatment of wastewater and exhaust gas. Clearly, alternate means of producing malonic acid and its esters are needed.
Biological systems for producing bio-based malonate via biological fermentation have been recently described (see U.S. Pat. No. 9,816,114). However, fermentative production of malonate creates new challenges for extracting and purifying the bio-based malonate produced, and for efficiently integrating extraction and purification processes into the overall production flow. There also remains a need for extracting and purifying diester derivatives of malonic acid, particularly those with substantially fewer impurities.
There remains a need, therefore, for improved methods, processes, and materials for extracting and purifying biosynthetic or bio-based malonate and diester derivatives of malonic acid in high yields with substantially fewer impurities from biological fermentation and improved methods, processes, and materials for the subsequent preparation of downstream chemicals and products.

This patent is subject to a terminal disclaimer.

Method for preparation of diester derivatives of malonic acid


A product dispenser utilizes an elastomeric tube which is compressed between a plunger and a frame by means of axially slidable members which support the plunger and frame for movement in equal and opposite directions so as to compress the tube and thereby force an aliquot portion of liquid from the tube. Release of the tube will cause the tube to return to its original position due to the elasticity of the tube.

This invention relates to a mechanism which dispenses measured aliquots of fluid from an elastic discharge tube or nipple of the type having a normally closed orifice.
Dispensing condiments and other fluid materials in the food processing industry is often accomplished by pumping mechanisms which utilize a discharge nozzle and a manually operated pump to effect the movement of fluid through a discharge tube. Spigots which have an "on" and "off" position may also be utilized for such a purpose.
There has developed and remained, however, the need for a mechanism which provides for discharge of an aliquot or measured portion of fluid from an elastic discharge nipple or nozzle.


A lamp socket for a vehicle includes a central electrode having a substantially rectangular button-shaped terminal disposed at the central part of a circular disc-shaped insulator and a coil spring for normally biasing the insulator. The button-shaped terminal is fixedly connected to a cord via a caulking portion and has the same sectional contour as that of a through hole formed through the insulator at the central part of the latter so as to allow the button-shaped terminal to be inserted therethrough, and a fitting groove is formed on said insulator at the position located angularly offset from the through hole by an angle of about 90.degree. so as to enable the button-shaped terminal to be fitted into the fitting groove. A clip portion is disposed on the rear surface side of the insulator so as to firmly hold the button-shaped terminal by engaging the caulking portion with the clip portion when the button-shaped terminal is inserted through the through hole and then turned by an angle of 90.degree..

A typical conventional lamp socket of the foregoing type is shown in FIG. 4. The lamp socket 90 is substantially constructed of a cylindrical outer sleeve 91 made of a metallic sheet material, a central electrode assembly 92 including member 93 molded of an insulation material, such as a resin, into a circular disc-shaped contour, a button-shaped conductive terminal 94 having an electric wire connected thereto (see FIG. 5), and a coil spring 95 adapted to expand and contract within the outer sleeve 91 by a predetermined distance while supporting the central electrode assembly 92. A connector terminal 96 is typically fixedly secured to the other end (right-hand end as seen in the drawing) of the electric wire 94b for making connection to a wiring system in the vehicle (not shown).
With the conventional lamp socket 90 constructed in the above-described manner, assembly of the central electrode assembly 92 is achieved by caulking the left-hand end of electric wire 94b to a terminal portion 94a to prepare the button-shaped terminal 94. Thereafter, the button-shaped terminal 94 is manually inserted through a fitting hole 93a by inserting the right-hand end of electric wire 94b into the front side of member 93, and subsequently, connecting the right-hand end of electric wire 94b to the connector terminal 96 as shown in FIG. 5. In other words, each assembling operation is continuously performed by conducting a plurality of steps in following the order: caulking step (94a to 94b) .fwdarw.inserting step (94b through 93a) .fwdarw.caulking step (94b to 96), resulting in a complicated assembly operation. Consequently, there arises a problem that productivity of a production line for producing lamp sockets is degraded.


A method of performing the computer-intensive initial steps of the range migration algorithm, or RMA, produces radar imagery of higher quality than the current polar format (PF) processing approach, while operating faster and more efficiently than the standard RMA. The new method is advantageous when the synthetic aperture length required to achieve azimuth resolution is significantly larger than the azimuth extent of the processed scene. The method subdivides the signal history into a plurality of non-overlapping subapertures, adds a low bandwidth azimuth chirp across each subaperture and applies a fast Fourier transform separately to each subaperture. The results are coherently combined, after which the remaining steps of the conventional RMA may be completed with minor modifications to the subsequent two-dimensional phase compensation. The invention is applicable to spotlight, stripmap and scan-mode SAR image formation, and the separate, subaperture Fourier transformations may be performed simultaneously.

Synthetic aperture radar, or SAR, has become an invaluable remote-sensing tool. To achieve the finest resolution, focused SAR is used, wherein some process is used to modify received signal histories to mitigate the detrimental effects of scatterer motion through range and doppler resolution cells. One approach to focussed SAR involves the use of polar format (PF) processing.sup.1. An alternative approach is based upon the range migration algorithm, or RMA, also known as the .OMEGA.-K algorithm and wave number processing. Both the PF and RMA techniques have their advantages and disadvantages.sup.2. PF is typically less computationally intensive and more memory efficient, but systems based on the RMA are capable of producing well-focused, fine-resolution images over a wider area scene. FNT .sup.1 Walker, J. L., "Range-Doppler Imaging of Rotating Objects," IEEE Transactions on Aerospace and Electronic Systems, Vol. AES-16, No. 1, January 1980, pp. 23-52. FNT .sup.2 Cafforio, C., C. Prati, and F. Rocca, "SAR Data Focusing Using Seismic Migration Techniques," IEEE Transactions on Aerospace and Electronic Systems, Vol. 27, No. 2, March 1991, pp. 194-206.
More specific advantages of the RMA over conventional PF processing include the following:
1. The RMA provides an exact solution to the problem of range curvature. Fine-resolution, large scene images produced using the RMA do not suffer the geometric (keystone) distortion or residual quadratic phase errors inherent in conventional PF processing; PA1 2. The RMA can produce large scene size images free of subpatch and subswath boundaries. Such images are better suited for coherent-based image enhancement and exploitation techniques; and PA1 3. The RMA is directly capable of processing spotlight, stripmap, and scan-mode SAR images. These advantages become increasingly significant with improvements in SAR system resolution and area coverage. The RMA is particularly useful in fine-resolution SAR systems operating at low frequencies, typically in systems designed for foliage penetration (FOPEN) and ground penetration (GPEN) applications.


A method and system for the avoidance of collisions among aircraft in which monochromatic radiation is transmitted from an aircraft fitted out with a wide-field optical transceiver. The monochromatic radiation scans the space around the aircraft which defines a zone of proximity. Optical radiation is returned after back reflection off objects which may be sources of danger constituted by other aircraft that have entered the zone of proximity. The radiation received is detected and then processed to deduce therefrom the direction and, as the case may be, the distance of the source of danger. Such a method can be applied especially to the avoidance of collision between non-cooperating aircraft.

1. Field of the Invention
The invention relates to the field of air traffic and, more particularly, its object is a collision-avoidance method for aircraft and an optical set to be taken on board aircraft in order to implement it.
The need for aircraft to be able to maneuver in conditions of low visibility or in dense traffic zones necessitates the use of systems enabling the avoidance of collisions.
2. Description of the Prior Art
Anti collision systems using transmission by radio or by radar waves have been developed.
Systems known as TCAS (Traffic Alert and Collision Avoidance Systems) use interrogators on the ground and transponders carried by aircraft capable of responding as interrogated, if necessary by the addition, to their response code, of information elements relating for example to their altitude. These systems, of the secondary surveillance radar type, are complicated systems that are very costly.
Other types of systems have been developed, using methods of communication by radio waves and therefore requiring radio dialog for the localization of danger or threats. These systems, apart from their complexity, cannot be used to obtain the fast responses that are indispensable in the event of a risk of collision, and some Of them are subject to the hazards of transmission in certain particular conditions, for example fading, echos, etc.

Method for the avoidance of collisions between aircraft and onboard optical set designed for its implementation


A vanity is disclosed having a mirror and a light source adjacent the mirror to illuminate an object to be viewed in the mirror. A cover panel is coupled adjacent to the light source for movement to an open position to reveal the mirror and a closed position to conceal the mirror. The vanity includes a switch device to activate and deactivate the light source and a positioning device to maintain the cover panel in the open or closed position. The switch device and the positioning device cooperate to activate the light source when the cover panel is in the open position and to deactivate the light source when the cover panel is not in the open position. The cover panel is configured for rotational movement between the open and closed position in a plane generally parallel to a plane of the mirror.

Vanities for use within vehicles are generally known and are typically provided on one side of a visor so that the visor may be folded-down to expose the vanity. The generally known vanities typically include a mirror having a lighting system with a light source such as a bulb and lens located adjacent to the mirror for illuminating an object to be viewed in the mirror. Such vanities also typically include a cover panel that is hinged adjacent to one end of the mirror so that when the visor is folded down, the cover panel may be opened to expose the mirror and the light source for use by an occupant of the vehicle and then folded closed to conceal the mirror.
However, such known vanities typically require a space adjacent to the visor and vanity within which the cover panel is configured to move about the hinges for exposing and concealing the mirror.
Accordingly, it would be advantageous to provide a vanity for a vehicle that provides a cover panel and a mirror that do not require a space adjacent to the mirror for movement of the cover panel between an open position to reveal the mirror and a closed position to conceal the mirror. It would also be advantageous to provide a vanity for a vehicle having a cover panel that is configured to rotate in plane generally parallel to a plane of the mirror to selectively conceal and reveal the mirror. It would be further advantageous to provide a vanity for a vehicle having a cover panel that activates a lighting system when the cover panel is opened, and that deactivates the lighting system when the cover is closed. It would be further advantageous to provide a vanity for a vehicle having a positioning device for maintaining the position of the cover panel in one of the open position and the closed position. It would be further advantageous to provide a vanity for a vehicle having a switch device that is integrated with the positioning device to activate the lighting system and illuminate objects for viewing in the mirror when the cover panel is moved to the open position, and to deactivate the lighting system when the cover panel is moved away from the open position.
Accordingly, it would be advantageous to provide a vanity for a vehicle having any one or more of these or other advantageous features.


Sunscreen compositions comprising one or more sunscreen agents (inorganic and combinations of inorganic and organic), one or more film forming polymers (synthetic or naturally derived), and heat treated xanthan gum. The sunscreen composition provides higher pre- and post-immersion SPF values, as well as a means for reducing the amount of sunscreen agents in a formulation without forfeiting efficacy.

1. Technical Field
The present invention is directed towards skincare compositions. More particularly, the present invention is directed towards sunscreen compositions having improved efficacy in protection from ultraviolet radiation.
2. Background Information
Consumers are increasingly concerned about the effects of ultraviolet ('UV') radiation on the skin, and with good reason. Skin cancer has become one of the leading forms of cancer, annually affecting millions globally. Demand for UV protection has made the sun care market one of the fastest growing personal care sectors.
Commercially viable sun care products should provide a variety of benefits, such as high Sun Protection Factor (SPF) values, protection from UV-A and UV-B radiation (also known as broad-spectrum protection), water resistance and rub-off resistance, aesthetically pleasing products, and convenient application.
When formulating these products, consumer use should be considered. For example, swimming or mild perspiration is often sufficient to remove most commercially available sunscreen formulations from a person's skin, necessitating multiple applications. Such repeated applications are inconvenient, costly and typically results in the consumer delaying reapplication of the sunscreen, which may lead to sunburn.
Accordingly, higher SPF values, broad spectrum protection, enhanced water and rub-off resistance, the need for aesthetically pleasing products, and convenience have become increasingly important in sun protection formulations. Further, formulators continue to search for ways to not only increase the SPF value of formulations, but also to increase the efficacy of a sunscreen without increasing the actual level of the sunscreen actives within the formulation.
Additionally, formulators are left with little choice in the type of rheology modifiers used in formulations, particularly those containing actives (or agents) such as inorganic particulate sunscreen agents. Historically, xanthan gum has been the thickener of choice; however, this thickener contributes no benefit with respect to SPF enhancement.
Film forming polymers are used widely in personal care products for functions such as hair fixatives, SPF retention, water resistance, rub-off resistance, fragrance retention, and so forth and are well known in the art. These polymers can be both synthetic and naturally derived. The polymers are typically used in a variety of applications, including sun protection, to enhance the water and rub-off resistance of the UV filters. With the advent of higher SPF products, the challenge has been to create these sun protection formulations without increasing either the use level of the polymer or UV filters or both. Doing so causes unpleasant aesthetics and increased cost.
Therefore, there is a need for a sunscreen formulation that provides both water resistance and higher SPE values when applied to a person, both before and after immersion in water, in particular, one that provides these benefits without the need to increase the amount of sunscreen active or agent.


Techniques are described for a data recovery validation test. In examples, a processor receives a command to be included in the validation test that is configured to validate performance of an activity by a server prior to a failure to perform the activity by the server. The processor stores the validation test including the command on a memory device, and prior to the failure of the activity by the server, executes the validation test including the command responsive to an input. The processor receives results of the validation test corresponding to the command and indicating whether the server performed the activity in accordance with a standard for the activity during the validation test. The processor provides the results of the validation test in a user interface.

Data backup is becoming increasingly important as more and more businesses move operations and information to digital forms. Generally, data backup includes the process of generating a copy of computer data, and storing the copy in a different location than the primary storage location of the original data, so that the data in the secondary location may be used to restore the original data after a data loss event. To ensure that data is backed up properly, and that the data is accessible once it has been backed up, a computer data manager may perform a validation operation to test the reliability of the data backup. However, creation and execution of such validation operations is typically slow and time consuming. Specifically, conventional systems require the data manager to "start from scratch" to create and/or locate scripts to run as part of the validation operation each time the manager desires to execute a validation operation, demanding substantial time and resources on behalf of the manager.

State Farm Mutual Automobile Insurance Company


Embodiments of the present invention generally provide methods for forming a silicon nitride layer on a substrate. In one embodiment, a method of forming a silicon nitride layer using remote plasma chemical vapor deposition (CVD) at a temperature that is less than 300 degrees Celsius is disclosed. The precursors for the remote plasma CVD process include tris(dimethylamino)silane (TRIS), dichlorosilane (DCS), trisilylamine (TSA), bis-t-butylaminosilane (BTBAS), hexachlorodisilane (HCDS) or hexamethylcyclotrisilazane (HMCTZ).

Field
Embodiments of the present invention generally relate to methods and processes for forming conformal silicon nitride films, including doped silicon nitride films, at low temperatures.
Description of the Related Art
The electronic device industry and the semiconductor industry continue to strive for larger production yields while increasing the uniformity of layers deposited on substrates having increasingly larger surface areas. These same factors in combination with new materials also provide higher integration of circuits per unit area on the substrate. As circuit integration increases, the need for greater uniformity and process control regarding layer characteristics rises.
For example, ultra-large-scale integrated (ULSI) circuits typically include more than one million transistors that are formed on a semiconductor substrate and which cooperate to perform various functions within an electronic device. Such transistors may include complementary metal-oxide-semiconductor (CMOS) field effect transistors. A CMOS transistor includes a gate structure that is disposed between a source region and a drain region defined in the semiconductor substrate. The gate structure (stack) generally comprises a gate electrode formed on a gate dielectric material.
Transistors may also be formed as 3 dimensional or 3D circuits as compared to traditional planar circuits. 3D transistors may employ gates that form conducting channels on three sides of a vertical "fin" structure, allowing chips to operate at lower voltage with lower leakage. Examples of three dimensional transistors having such gate structures include a FinFET (a nonplanar, double-gate transistor built on a silicon-on-insulator technology substrate, based on the earlier DELTA (single-gate) transistor design) or a Trigate transistor structure.
Conformal coverage with low pattern loading effect of dielectric films on high aspect ratio structures and/or 3D structures are of critical requirement as device node shrinks down to below 45 nm, such as to the 22 nm level, and as the manufacture of 3D transistors increases. Silicon nitride films, including doped silicon nitride, may be used throughout integrated circuit formation, such as gate spacers, liner layers, sacrificial layers, barrier layers, etc. Silicon nitride films formed using thermal processes offers good conformality. The drawbacks, however, include a high temperature requirement (typically greater than 400° C.) and few capabilities to engineer film compositions and properties for different applications. Alternatively, conventional silane-based plasma enhanced chemical vapor deposition (PECVD) silicon nitride films have poorer step coverage due to directionality of radicals' fluxes. Additionally, tuning conformal layers to have desired film properties has also been difficult, particularly as the feature size decreases and the use of non-planar structures increases.
Therefore, there is a need for a low temperature process to form conformal silicon nitride films with micromodulated texture, composition and stable film properties.

Low temperature silicon nitride films using remote plasma CVD technology


In accordance with the present invention, methods and structures are provided for the treatment of functional spinal unit injuries through the use of light activated gene therapy to induce bone fusion through the introduction of a desired gene into a patient's spinal tissue. Methods and structures are also provided for the utilization of ultraviolet light activated gene therapy to repair/rebuild an injured intervertebral disc through the introduction of a desired gene into a patient's spinal tissue. An implant system including a light probe and an implant with which r-AAV is integrated is also provided.

1. Field of the Invention
The present invention relates to the field of gene therapy. According to the present invention, methods are provided for the treatment of functional spinal unit injuries through the use of light activated gene therapy to introduce a desired gene into a patient's tissue. An embodiment of the present invention includes methods for the utilization of light activated gene therapy to repair/rebuild an injured intervertebral disc. Alternate embodiment provide an implant system having UV activated viral vector integrated with an implant.
2. Description of the Related Art
Currently, treatment for injured spines often involves "fusion" or inciting the biological union of bones by inserting bone grafts or devices within the functional spinal units (FSU), e.g., between two vertebra. In addition, the effective manipulation of certain osteobiologic molecules via gene therapy can be used to incite bone fusion within a functional spinal unit (FSU). A FSU is composed of two vertebra, a nearby nerve root, and a human interverterbral disc between the two vertebra. This disc, which cushions shock to the spine and lends stability to the FSU, is composed of water, collagen (Type I and II), and glycosaminoglycans (GAG).
An aging or degenerate disc is often characterized by reduced water, increased Type I collagen, decreased Type II collagen, and decreased GAG. This aging or degenerating, which is incompletely understood, generally results in decreased biomechanical shock absorption, increased range of motion and pain and/or disability.
Somatic cell gene therapy is a form of treatment in which the genetic material of a target cell is altered through the administration of nucleic acid, typically in the form of DNA. In pursuit of effective in vivo administration routes, scientists have harnessed the otherwise potentially deleterious ability of viruses to invade a target cell and "reprogram" the cell through the insertion of viral DNA. By encapsulating desirable genetic material in a viral particle, or "vector," minus some of the viral DNA, the effective and targeted delivery of genetic material in vivo is possible. As applied to spinal specific treatments, gene therapy offers the ability to make use of osteobiological molecules, including both intracellular and extracellular proteins, to incite bone fusion and/or disc repair.
In particular, the desirable qualities of adeno-associated viruses (AAV) have led to further study of potential gene therapy uses. As a vehicle for gene therapy recombinant forms of AAV, or r-AAV, offer many advantages including the vector's ability to infect non-dividing cells (e.g., chondrocytes, or cells within cartilage), the sustained target gene expression, the low immune response to the vector, and the ability to transduce a large variety of tissues. The AAV contains a single strand DNA (ssDNA) genome. Under normal conditions, AAV is present in humans in a replication incompetent form, due to the fact the AAV alone does not encode the enzyme required for replication of the second DNA strand. Successful r-AAV transduction often requires the presence of a co-infection with an adenovirus or the exposure of the host cell to DNA damaging agents, such as γ-irradiation. The introduction of either the co-infection or the DNA damaging agents dramatically induces the rate limiting step of second strand synthesis, i.e. the second strand of DNA which is synthesized based on the vector inserted first strand. However, making use of these DNA damaging agents is impractical because the administration of an adenovirus co-infection to a patient is not practical or desirable and the site specific and safety issues involved with using γ-irradiation are undesirable as well.
In the past, attempts have been made to induce r-AAV transduction in vitro using UV radiation having a wavelength of 254 nm. Unfortunately, no effective therapeutic method or apparatus was developed based on these experiments due to the long exposure times involved with using 254 nm UV radiation, the difficulties of delivering 254 nm UV radiation to a surgical target site, and the inability to position the 254 nm UV light source so as to allow effective penetration of a target cell.

Method for introducing an ultraviolet light activated viral vector into the spinal column


An apparatus and method for determining the concentrations of hydrogen isotopes in a sample. Hydrogen in the sample is separated from other elements using a filter selectively permeable to hydrogen. Then the hydrogen is condensed onto a cold finger or cryopump. The cold finger is rotated as pulsed laser energy vaporizes a portion of the condensed hydrogen, forming a packet of molecular hydrogen. The desorbed hydrogen is ionized and admitted into a mass spectrometer for analysis.

1. Field of the Invention
The present invention relates to analysis of the isotopic concentration of an element. In particular, the present invention relates to analysis of the concentration of hydrogen-isotope-containing mixtures. The United States Government has rights in this invention pursuant to Contract No. DE-AC09-89SR18035 between the U.S. Department of Energy and Westinghouse Savannah River Company.
2. Discussion of Background
Isotopes are atoms of the same element that differ in their number of neutrons; thus, they have slightly different masses. It is often desirable to measure the concentrations of isotopes in a sample containing one or more elements in a mixture, that is, the relative amounts of the isotopes of each element which are found in the sample. The isotopic concentration of hydrogen in particular is important. Hydrogen has three isotopes, called protium (H), deuterium (D), and tritium (T) to reflect the number of neutrons in their respective nuclei (one, two and three, respectively). Molecular hydrogen may include the combinations HD, HT, and DT as well as H.sub.2, D.sub.2, and T.sub.2. The isotopic concentration of a hydrogen sample thus may include any one or some combination of these possibilities. (The term "hydrogen" is used throughout this specification in the elemental sense rather than the isotopic sense.)
Deuterium and tritium, in particular, are useful and valuable isotopes; they are also radioactive isotopes. In nuclear material production processes, it is important to determine the relative amounts of the various isotopes that are produced, as well as to monitor the facilities to assure worker safety. The concentrations of hydrogen isotopes in air are frequently measured in the course of environmental testing and monitoring. The ratio of deuterium to hydrogen (D/H ratio) is useful in dating soil and minerals exposed to solar wind irradiation, in analysis of planetary atmospheric gases, and, in analyzing the solar wind, to provide a limit for the D/H ratio in the sun (see Low, U.S. Pat. No. 3,666,942).
Methods for determination of hydrogen isotope concentration include deuterium separation by gas chromatography, mass spectrometry, high-resolution techniques such as Fourier Transform Mass Spectrometry (FTMS), and infrared absorption analysis of gas samples.
Low et al. (U.S. Pat. No. 3,666,942) describe a method for determining the amount of deuterium in a mixture containing hydrogen and low concentrations of deuterium, such as might be found in typical terrestrial hydrogen samples. A sample of the mixture is passed through a hydrogen-selective film to remove gases other than hydrogen. The hydrogen is carried to a chromatographic detector for a measurement of total hydrogen content, then to an ionization chamber where it is ionized to form an effluent containing HD.sup.+ ions. The effluent is delivered to a high resolution infrared detector whose output signal depends on the HD.sup.+ concentration. The ratio of the two signals is proportional to the H/D ratio of the initial sample.
A quadrupole mass spectrometer (QMS) can be used for separating isotopes, as in the system described by Habfast et al. (U.S. Pat. No. 5,043,575). A quadrupole mass filter is provided with a voltage supply device controlled by the ion separation system. The supply voltages of the filter are switched over synchronously with the varying mass deflection setting of the ion separation system, thereby controlling the range of masses allowed through the filter.
Pokar et al. (U.S. Pat. No. 4,039,828) show a QMS system for analyzing corrosive gases or gases tending to sublimate. The sample beam is collimated by an aperture before it enters the ionization chamber. The gas molecules which do not pass through the aperture are condensed out onto a liquid nitrogen cryopump, or "cooling finger."
Many of the presently-available methods for analyzing hydrogen isotope concentrations suffer from poor resolution due to interactions between the ions in the ion source or ion separator, homogeneity errors, and other sources of error. High-resolution systems such as FTMS are often prohibitively expensive: a typical FTMS system can cost ten times as much as a quadrupole mass spectrometer (QMS). Furthermore, adsorption of hydrogen isotopes on the walls of the system may decrease resolution due to "memory" effects. Such adsorbed hydrogen is difficult to eliminate and leads to errors in subsequent measurements. Finally, there is no known method which both minimizes adsorption effects and provides accurate and complete information about the isotopic concentration of a sample having a known volume, that is, the relative amounts of H.sub.2, D.sub.2, T.sub.2, HD, HT, and DT found in the sample.

The United States of America as represented by the United States Department of Energy


A metering valve (2) and a device (1) provided with it for metered dispensing of a preferably cosmetic liquid (3) and a process for producing such a metering valve (2) and a use of such a metering valve (2) are suggested. The metering valve has a valve element (6) with a spring section (21) which is elastic in the direction of motion and which bears a sealing element (14). This allows especially sealed contact with the assigned valve seat when the inlet valve (9) is closed.

1. Field of the Invention
This invention relates to a metering valve for dispensing a preferably cosmetic liquid, a device with such a metering valve, a process for producing such a metering valve, and use of such a metering valve or such a device.
2. Description of Related Art
The concept of "cosmetic liquid" includes in a narrow sense hair spray, hair lacquer, a deodorant, a foam, a gel, a coloring spray, a sunscreen or skin care agent or the like. Preferably, in a wider sense also other body care products, cleaning products, cosmetics, or the like, and also suspensions and fluids, especially with gaseous phases, are included. But other liquids, for example air fresheners, and especially also technical liquids and fluids, such as rust looseners or the like, can also be used. But for reasons of simplification and based on the focus of use often only cosmetic liquids are addressed below.
U.S. Patent Application 2003/0230603 A1 (U.S. Pat. No. 6,978,916) discloses a device for metered atomization of a cosmetic liquid, a container which contains the liquid having a metering valve with a movable valve element in a valve housing. The valve element together with the valve housing forms a supply-side inlet valve and a dispensing-side outlet valve. The valve element is preferably provided with a slipped-on spray head or the like for dispensing and atomization of the liquid. By pressing down on the spray head, the valve element is moved axially, by which, first, the supply-side inlet value of the metering valve is closed and only then is the dispensing-side outlet valve of the metering valve opened. Then, the liquid which preferably contains a propellant can escape from the metering space formed in the valve housing and can be atomized and delivered by the connected spray head.
To achieve the desired sealing action between the valve element, on the one hand, and the valve housing, on the other, a seal is injected onto the movable valve element and seals axially when the inlet valve is closed. The known metering valve does not allow optimum sealing.

Metering valve and device for dispensing a preferably cosmetic liquid


While fluid pressure is present on the upstream side of a ball valve assembly, a jig is mounted to the downstream flange of the ball valve assembly. The jig has two hinged arms. A jack-screw pad engages the ball while one or the other of the arms is positioned at the screw and urged by a jam nut on the screw to force the pad against the valve ball to seal it on the inboard valve seal. Then the outboard seal is removed and replaced during sequential use of the hinged arms to keep the inboard seal holding pressure on the upstream side.

1. Field of the Invention
This invention relates generally to ball valves, and more particularly to apparatus and a method for replacement of the downstream seal of such valves.
2. Description of the Prior Art
Ball valve assemblies are widely used in piping systems. Typically they have a valve body with a passageway through it and which opens at opposite flanged faces of the valve body, with the opening at the center of the face and a large flange with bolt receiving holes by which the valve body can be bolted to flange piping. Such valves are often used in a system in which the flow is usually in one direction from an upstream, higher pressure side to a downstream side. However, it is not uncommon for ball valves to be used in systems in which the pressure differential across the valve can be in opposite directions at different times.
When such valves are used on fittings to enable supply of material to or removal of material from a tank, such as on a tanker truck or railroad car, occasions arise when it is desirable to replace one or both seals. If the application is in a tanker wherein there is piping or a hose external to the valve assembly to supply material to the tank or remove it from the tank, but not always in place, it is desirable to be able to replace the outboard valve seal without emptying the tank. In other words, it is desirable to be able to replace the outboard seal even if there is pressure in the tank. Heretofore, to the best of my knowledge, that has not been possible in conventional ball valve assemblies, without removing the pressure from the tank. In many instances, has necessitated draining the product from the tank before seal replacement. Therefore, it is an object of the present invention to facilitate removal of the outboard seal from a ball valve assembly, and replacement of the seal, while the tank or plumbing line upstream of the valve body remains pressurized.

Ball valve seal replacement apparatus and method

Electromechanical Research Laboratories, Inc.


A logging process in a data storage system having a set of storage tiers, each storage tier of the set of storage tiers having different performance characteristics, wherein the set of storage tiers is divided into a plurality of subsets of storage tiers using the performance characteristics, may include initiating the logging process for creating a separate log file for each of the plurality of subsets of storage tiers for maintaining a history of data changes in the subset of storage tiers, thereby creating a plurality of log files. In response to a change in data stored in at least one storage tier of a subset of storage tiers of the plurality of subsets of storage tiers, one or more log records including information about the change may be generated and written into respective log files.

The invention relates to computing systems and, more particularly, to a method for a logging process in a data storage system.
The temperature-based storage in commercial databases becomes one of the more important technologies for different sized companies. It is intended to reduce the storage cost. However, backup and restore functions need to be optimized for an optimal use of the temperature-based storage technique.

Logging process in a data storage system

INTERNATIONAL BUSINESS MACHINES CORPORATION


A screw driver for housing and supplying bits has a housing with a elongate tube extending through the housing along the axis to a forward presentation end of the tube at which the bits are presented for use. The housing has a rotatable storage holder mounted in the housing for holding and storing a plurality of tool bits and arranged by manual engagement with an exposed side portion to rotate about a second axis parallel to the tube. A plunger carried on an end cap with a hexagonal sleeve has a flat magnetic bit carrying face at the forward end and receives a cooperating portion of the housing as a sliding fit. The holder is removable by pressing an ejection button on an opposite face of the housing and has a magnet which holds the bits in place. The plunger is restricted against free sliding movement by a friction head which presses against the side of the plunger.

A tool such as a screwdriver or the like, generally, comprises a handle that has a portion which extends forwardly for rotation a single type of screw. Some screwdrivers are adapted to allow an operator to change the bit for use with different types of screws so that only one screwdriver is needed in place of many different types. These changeable screwdrivers, generally, require the operator to manually remove the bit from the screwdriver and replace it with an new one, which causes a chance that the bit may be lost or misplaced. Many times the bits are held in the handle which can be opened to allow access.
The screwdriver of the present invention can be used for screw driving bits, sockets, drill bits or other bits which have a different operation and need to be changed within the driver for different jobs.
Examples of screw drivers of this general type are shown in U.S. Pat. Nos. 6,134,995 (Shaio) issued Oct. 24th, 2000, U.S. Pat. No. 6,502,484 (Pao-Hsi) issued Jan. 7th, 2003 and U.S. Pat. No. 6,601,483 (Wannop) issued in 2003.

Interchangeable screwdriver for tool bits


Provided is piezoelectric actuator includes; a vibrating plate; a first electrode provided on the vibrating plate; a first seed layer provided on the first electrode; a second seed layer provided on the vibrating plate at least at a position adjacent to the first electrode; a first piezoelectric layer provided on the first seed layer, the first piezoelectric layer and has a perovskite structure; a second piezoelectric layer that is provided to cover the first piezoelectric layer and the second seed layer; and a second electrode that is provided on the second piezoelectric layer. The first piezoelectric layer and the second piezoelectric layer are preferentially oriented to a (100) face.

1. Technical Field
The present invention relates a piezoelectric actuator, a liquid ejecting head, and a method of manufacturing a piezoelectric actuator.
2. Related Art
In a piezoelectric element that is used in an ink jet type recording head that is known as a representative example of a piezoelectric actuator, and the like, it is demanded for a crystal system thereof to be oriented in a (100) face in a rhombohedral crystal so as to actually raise piezoelectric characteristics of a piezoelectric layer. In addition, a method of manufacturing a piezoelectric element is disclosed (for example, refer to JP-A-2011-238774). In the method, a piezoelectric layer composed of lead zircornate titanate (PZT) is formed on a lower electrode through a lead titanate layer in order for the lead zircornate titanate to be preferentially oriented to the (100) face. In addition, a technology, in which a lanthanum nickel oxide (LNO) is used as a seed layer, and a bismuth ferrate-based and bismuth titanate-based piezoelectric layer is preferentially oriented to the (100) face, is disclosed (for example, refer to JP-A-2012-006182). In addition, a buffer layer, which is constituted by a metal element capable of forming a B site of a PZT crystal, is preferentially oriented to the (100) face as a seed layer, is also suggested (for example, refer to JP-A-2005-340428).
However, when manufacturing ink jet type recording head, the piezoelectric layer is also formed on an insulator layer that becomes a nonactive portion in addition to a lower electrode that becomes an active portion, but the piezoelectric layer may not be effectively oriented due to an influence by the base. In addition, there is a problem that fluctuation in the orientation occurs at a boundary between the active portion and the nonactive portion, and thus a degree of orientation locally decreases. Such a decrease in the degree of orientation causes a decrease in an amount of displacement and occurrence of cracks.
In addition, the problem exists not only in the ink jet type recording head but also in other liquid ejecting head that ejects liquid droplets other than ink. In addition, the problem also exists in a piezoelectric element or a piezoelectric actuator which is used in devices other than the liquid ejecting heads.

Piezoelectric actuator, liquid ejecting head, and method of manufacturing piezoelectric actuator


An optical label-switching method and apparatus in which a payload signal is modulated on an optical carrier through differential phase-shift keying (DPSK) by a Mach-Zehnder modulator (MZM), and a label signal is imposed on the DPSK signal by the same MZM through an optical amplitude change effected by modulating the DPSK drive signal or MZM bias.

Optical packet switching (OPS) and optical burst switching (OBS) are considered as next-generation transport technologies that will enable more efficient and flexible utilization of optical network capacity by providing sub-wavelength granularity. Optical label switching is a promising packet switching scheme that offers a number of features that are important to future data-intensive networks such as protocol and format independent transparency at the all optical data plane, simplification in the control plane and interoperability with legacy and emerging networking technologies including Generalized Multiprotocol Label Switching (GMPLS). Such a switching scheme was discussed by D. J. Blumental et al in a publication entitled "All-Optical Label Swapping Networks and Technologies", which appeared in the Journal of Lightwave Technologies, Vol. 18, pp. 2058-2075 in 2000, the entire contents of which are incorporated herein by reference.
One optically labeled packet transmission based on an orthogonal intensity modulation/differential phase shift keying (IM/DPSK) modulation format—in which payloads are intensity modulated while labels are carried by DPSK—has been proposed and demonstrated. (See., e.g., T. Koonen, et al, "Optical Packet Routing In IP-Over-WDM Networks Deploying Two-Level Optical Labeling", Proc. Eur. Conf. Optical Communications (ECOC 2001), pp. 14-15, 2001; N. Chi, et al, "Dispersion Management for Two-Level Optically Labeled Signals in IP-Over-WDM Networks", Proc. Eur. Conf. Optical Communications (ECOC 2002), Paper 5.5.1, Copenhagen, Denmark, 2002; T. Koonen et al, "Optical Labeling Of Packets in IP-over-WDM Networks" Proc. Eur. Conf. Optical Communications (ECOC 2002), Paper 5.5.2, Copenhagen, Denmark, 2002; and N. Chi etal, "Transmission and Transparent Wavelength Conversion of an Optical Labeled Signal Using ASK/DPSK Orthogonal Modulation", IEEE Photon. Tech. Lett., vol 15, pp. 760-762, May 2003).
Unfortunately, a number of significant drawbacks characterize these schemes. For example, since DPSK is carrying low-speed label information, a delay interferometer—which is needed in DPSK demodulation—produces a long delay difference between the two arms of the delay interferometer thereby resulting in significant temperature and polarization sensitivities. In addition, any change in the data rate of the label requires a change to the delay of the interferometer (to obtain a matched delay).
A further characteristic of such prior art schemes is that the removal and insertion of a label is not easily performed since the label is phase modulated. More specifically, to remove a label, cross gain modulation is used which changes the signal wavelength and therefore is undesirable in situations where signal wavelength needs to be maintained. To add a label, expensive phase sensitive modulation is required. Finally, low speed DPSK requires a high-coherence (narrow linewidth) source (CW) laser and is less tolerant to nonlinear effects such as cross-phase-modulation (XPM).
Other schemes utilizing frequency shift keying (IM/FSK) (See, e.g., G. K. Chang et. al., "Multirate Payload Switching Using a Swappable Optical Carrier Suppressed Label In a Packet-Switched DWDM Optical Network", J. Lightwave Technol., vol 23, pp. 196-202, January 2005), subcarrier modulation (IM/SCM) (See, e.g., M. Hickey et. al. "Combined Frequency and Amplitude Modulation for the STARNET WDM Computer Communication Network", IEEE Photon. Technol. Lett., Vol. 6, pp. 1473-1475, December 1994), or polarization shift keying (PoISK/IM) (See, e.g., C. W. Chow, et. al., "Optical Packet Labeling Based on Simultaneous Polarization Shift Keying and Amplitude Shift Keying", Optics Letters, Vol. 29, pp. 1861-1963, August 2004) have also been demonstrated.
More recently, it has been shown that using DPSK/IM for payload/label modulation and using a balanced receiver for DPSK detection provides superior receiver sensitivity of around −36 dBm for both the label and payload at a bit error rate (BER) of 10−9. (See, e.g., X. Liu, et. al., Optical-Label Switching Based on DPSK/ASK Modulation Format With Balanced Detection For DPSK Payload", Proc. Eur. Conf. Optical Communications (ECOC 2003), Paper Tu4.4.3, Rimini, Italy, 2003; and X. Liu, et. al., "Transmission of an ASK-Labeled RZ-DPSK Signal and Label Erasure Using a Saturated SOA", IEEE Photon. Technol. Lett., Vol 16, pp. 1594-1596, June 2004).
In a majority of these optical label encoding schemes, two optical modulators are required, one for encoding the payload and the other for the label. Consequently, such schemes are not particularly cost-effective and not easy to work with since the polarization state of the signal needs to be constantly maintained and its alignment when entering the two optical modulators is critical.

Optical label switching scheme employing differential phase-shift keying for payloads and intensity modulation for labels using a single optical modulator


A semiconductor component with a drift region and a drift control region. One embodiment includes a semiconductor body having a drift region of a first conduction type in the semiconductor body. A drift control region composed of a semiconductor material, which is arranged, at least in sections, is adjacent to the drift region in the semiconductor body. An accumulation dielectric is arranged between the drift region and the drift control region.

The invention relates to a power semiconductor component, having a low on resistance.
One important aim in the development of power semiconductor components is to produce components which have the highest possible blocking capability and which nevertheless have a low on resistance and which simultaneously have the lowest possible switching losses.
One possibility for reducing the on resistance of a power semiconductor component for a given blocking capability is to use the compensation principle, described for example in U.S. Pat. No. 4,754,310 (Coe), U.S. Pat. No. 5,216,275 A1 (Chen), U.S. Pat. No. 5,438,215 or DE 43 09 764 C2 (Tihanyi).
A further possibility for reducing the on resistance of a semiconductor component is to provide a field electrode insulated dielectrically from the drift region. Components of this type are described in U.S. Pat. No. 4,903,189 (Ngo), U.S. Pat. No. 4,941,026 (Temple), U.S. Pat. No. 6,555,873 B2 (Disney), U.S. Pat. No. 6,717,230 B2 (Kocon) or U.S. Pat. No. 6,853,033 B2 (Liang).
EP 1 073 123 A2 (Yasuhara) describes a lateral power MOSFET having a plurality of auxiliary electrodes which are arranged in a drift region of the component and which are insulated from the drift region by a dielectric. The auxiliary electrodes are composed of a semi-insulating polysilicon (SIPOS) or a resistive material and are connected between a source connection and a drain connection of the component. The auxiliary electrodes bring about the formation of a depletion zone (depletion layer) in the drift region when the component is driven in the off state.
GB 2 089 118 A describes a power MOSFET having a resistive layer which extends along the drift region between a gate electrode and a drain electrode and which "spreads" an electric field in the drift region with the aim of increasing the dielectric strength.
U.S. Pat. No. 5,844,272 (Söderbärg) describes a lateral high-frequency transistor with a drift region running in the lateral direction of a semiconductor body.
US 2003/0073287 A1 (Kocon) proposes providing a plurality of field electrodes along the drift path of a semiconductor component, the field electrodes being at different potentials.

Semiconductor component with a drift region and a drift control region


The input digital signal is divided into blocks each composed of a number of samples, and first block floating is applied to each block. The each first block floating processed block is orthogonally transformed to provide spectral coefficients. The spectral coefficients are divided into bands, each band including at least one spectral coefficient. Second block floating is applied to each band to provide a second block floating processed band. Each of the second block floating processed bands is adaptively quantized by the adaptive bit allocation circuit. Common circuitry or processing is used to determine the block size and to apply block floating, which reduces the complexity of the hardware and/or the number of processing steps required.

Data compression techniques are known in which a digital audio or similar signal is divided in the time domain into blocks, each block is transformed using an orthogonal transform, and the resulting spectral coefficients are divided into plural bands of plural spectral coefficients. Block floating is applied to each band of the resulting spectral coefficients and each band of spectral coefficients is quantized. Information concerning the block floating and the information concerning quantization is transmitted or recorded on a recording medium simultaneously with the quantized data.
Block floating is a normalization process applied to a block of data comprising plural words, such as a band of plural spectral coefficients. Block floating is applied by multiplying each word in the data block by a common value for the data block to improve quantization efficiency. In a typical block floating process, the maximum absolute value of the words in the data block is found and is used as a block floating coefficient common to all the words in the data block. Using the maximum absolute value in the band as the block floating coefficient prevents data overflow because the absolute value of no other word in the data block can be greater than the maximum absolute value. A simplified form of block floating determines the block floating coefficient using a shift quantity, which provides block floating in 6 dB steps.
The orthogonal transform is normally carried out using a word length that is selected to be long enough so that a required accuracy can be achieved for any input data without using block floating. If the orthogonal transform is to be carried out without lowering the accuracy of the input data, a large word length is required. This results in increased hardware complexity and increased cost.
It is also known to improve analysis accuracy of the orthogonal transform by performing the orthogonal transform on the input signal divided into blocks having a variable block size. The block size is selected depending on the dynamic properties of the input signal. In some instances, the mean square value of the difference between adjacent samples of the input signal is used as a judgment index for determining the block size. The need to determine the judgment index exclusively for deciding on the block size for the orthogonal transform increases the number of processing steps.
In addition, when block floating is applied using the maximum absolute value of the words in the data block as the block floating coefficient, the absolute value of each word in the block is determined. Then, a sequence of determining whether the absolute value of the current word is greater than the maximum absolute value of the words already examined is repeated for all of the words in the data block. This results in an increased number of steps of the operating program and prolonged operating time.
FIG. 1 shows a flow chart of a conventional block floating program that applies block floating to a data block composed of plural words, for example, a band of spectral coefficients. Referring to FIG. 1, the absolute value of the current word is calculated at step S1. At the next step S2, the absolute value of the current word is compared to the maximum absolute value of the words in the data block already examined. If the maximum value of the current word is larger than the maximum absolute value, the current word is exchanged with the maximum absolute value at step S3, and becomes the new maximum absolute value, and the program proceeds to step S4. Otherwise, the program proceeds directly to step S4. Step S4 determines whether all of the words in the block have been processed. If the result is NO, the program reverts to step S1 and, if the result is YES, the program proceeds to the normalizing processing of step S5 onwards.
At step S5, the maximum absolute value for the block is shifted by one bit to the left. The most significant bit of the shifted word is tested at step S6. If the most significant bit is not a 1, the program reverts to step S5. The left shift process is repeated until the most significant bit of the shifted word is determined to be a 1 at step S6. The number of shifts immediately preceding the detection of a 1 is stored as the shift quantity, which can serve as the block floating coefficient. At the next step S7, each word in the block is normalized by shifting it to the left by the stored shift quantity. Step S8 checks whether all of the words in the data block have been normalized. If the result is NO, the program reverts to step S7 and, if the result is YES, the program terminates.
In the process just described, it is necessary to compare, for each word in the data block, the absolute value of the word with maximum absolute value of the words in the data block already examined. This requires a large number of the program steps and long processing time.

Data compressing and expanding apparatus with time domain and frequency domain block floating


A water treatment apparatus and method for softening "problem water". The apparatus includes a pair of treatment tank assemblies, each tank including serially connected filter and ion exchange beds. When a tank assembly requires regeneration, the tank assembly is taken off line and is regenerated using a regenerating apparatus that communicates a mixture of citric acid and brine solution to the ion exchange bed, followed by brine solution alone to form a barrier. A mixture of sodium carbonate and brine solution is then communicated to the ion exchange bed followed by a backwashing step which conveys treated water through both the ion exchange bed and the filter media in a counter flow direction. The regeneration apparatus includes a brine venturi and a chemical draw venturi connected in a parallel flow relationship and solenoid control valves for selectively communicating either a citric acid reservoir or a sodium carbonate reservoir to the chemical draw venturi. A timer or sequencer sequentially activates the control valves for predetermined time intervals. A heater and insulation is provided for the sodium carbonate reservoir to inhibit precipitation of the sodium carbonate out of solution. The regeneration apparatus also includes a flushing arrangement for flushing a fluid path along which the sodium carbonate solution flows during regeneration.

Water softeners of the "ion exchange"-type typically include a resin tank through which hard water passes to exchange its "hard" ions of calcium and magnesium for "soft" sodium ions from the resin bed. Regeneration of the resin bed is required periodically to remove the accumulation of hard ions and replenish the supply of soft ions. Regeneration is typically effected by flushing a brine solution through the resin bed. A water softener of this type is more fully described in U.S. Pat. No. 3,891,552 issued Jun. 24, 1975 to William Prior and James W. Kewley, entitled CONTROL VALVE FOR WATER SOFTENERS.
Modern water softeners of the type disclosed in U.S. Pat. No. 3,891,552 typically employ a brine tank which includes a reservoir and supply of salt disposed at a level above the bottom of the reservoir. A tube connected to a source of water establishes a path for water to flow to the reservoir. Upon the attainment of a predetermined level in the reservoir, the water reacts with the salt supply to produce a source of brine for regeneration of the resin bed. When regeneration is required, the brine is aspirated through the same tube that supplied water to the reservoir. The amount of water introduced to the brine tank after the regeneration cycle and the amount of brine aspirated from the tank during a regeneration cycle is controlled by a brine valve mechanism.
Commercially available water softeners generally include one or two tanks which contain the softening chemicals that form the resin beds. In one type of two-tank water softener, one tank is regenerated and kept "off-line" while the other tank is "on-line." A control valve controls the communication of the tanks with the household water supply and controls the timing and sequence of regeneration. An example of such a control valve is disclosed in U.S. Pat. No. 3,891,552. An improved control valve is described in U.S. Pat. No. 4,298,025. Both of these patents are owned by the present assignee and are herein incorporated by reference.
A prior art resin tank typically comprises an elongate cylinder in which the ion exchange resin is contained. A conduit, often called a riser pipe, extends downwardly from the top of the tank. A filter screen, mounted at the end of the conduit prevents the entry of resin into the conduit. An opening is formed in the top of the tank for discharging or admitting fluid depending on the direction of the flow.
In many applications, prior art water softeners such as the one described in the above referenced patent, perform satisfactorily. However, in some areas of the country "problem water" is encountered which is not easily treated by conventional water softening apparatus. In particular, in some regions, the water has a high iron content and a relatively low pH. When a standard water softening apparatus is used to treat this type of water, the result is usually considered unacceptable or marginally acceptable.
Methods and apparatus are known or have been suggested for treating water having a high iron content and low pH. Examples of specialized treatment systems are disclosed in U.S. Pat. Nos. 4,764,280 and 4,804,465, both of which are owned by the assignee of the subject application and are hereby incorporated by reference. Industrial type apparatus and methods are also known for treating problem water but, many if not most are considered uneconomical for home use or use a process that the average homeowner is not equipped to handle.
Ion exchange resins are also known which are especially effective for use in treatment systems for "problem" water. One such resin is available from the Rohm & Haas Company and is identified as Amberlite.RTM. DP-1 resin.
Amberlite.RTM. DP-1 cation exchange resin and other carboxylic acid exchange resins have the following general selectivity sequence, H.sup.+ >Ca.sup.++ >Mg.sup.++ >Na.sup.+. This selectivity sequence is reflected in the buffering capacity of the Na.sup.+ form of the cation exchange resin in water with a pH between 5-7 and the readiness of the resin to exchange Na.sup.+ for Ca.sup.+ + or Mg.sup.+ +. The buffering capacity of the cation exchange resin allows the use of the resin in a water softener in applications where the source water has a pH between 5-7 without requiring the use of caustic feeders or calcite neutralizers.
When used in a water softener, Amberlite.RTM. DP-1 will exchange with cations in aqueous solution by the following reaction: ##STR1##
Buffering of acidic water, containing dissolved carbon dioxide (CO.sub.2), occurs by the following reaction: R--COO.sup.- Na.sup.+ +H.sub.2 O+H.sub.2 CO.sub.3 -->R--COOH+NaHCO.sub.3 +H.sub.2 O Sodium bicarbonate, NaHCO.sub.3, as a 0.1 molar solution, has a pH of 8.4.
Regeneration of Amberlite.RTM. DP-1, because of the resin's unusual affinity for divalent and trivalent cations and buffering ability, has previously been regenerated with strong acid/alkali solutions or a solution of sodium citrate or sodium fumarate. Amberlite.RTM. DP-1 cannot be regenerated with brine in the same manner as conventional, sulfonic acid, water ion exchange resins are regenerated.
In Rohm and Haas U.S. Pat. No. 4,071,446, 4,116,860 and 4,083,782 , methods and compositions for regenerating sodium carboxylate ion exchange resins such as Amberlite.RTM. are described and are hereby incorporated by reference. Two of the methods described in these references for regenerating the ion exchange resin back to the sodium carboxylate form are the acid/alkali system and the sodium citrate or sodium fumarate systems.
The acid/alkali regeneration process is generally composed of the following steps:
1. Optional back wash; PA1 2. Acid regeneration, wherein a dilute sulfuric acid solution or preferably a hydrochloric acid solution is used to wash the resin to convert the carboxylate ion back to the acid form and dissolve any accumulated iron or other metal oxides; PA1 3. Water rinse; PA1 4. Caustic feeder wherein a caustic solution such as sodium hydroxide, sodium carbonate or sodium bicarbonate in an amount sufficient to neutralize from 70-96% of the theoretical exchange capacity of the resin is passed through the exchange bed. PA1 5. Slow rinse. PA1 6. Hold. PA1 7. Final Rinse. PA1 8. Final back wash.
The sodium citrate or sodium fumarate system is a one step regenerating composition that is safe for a residential environment. The regenerating solution for a residential water system would be a mixture of 75 weight percent sodium chloride, 15 weight percent sodium citrate and 10 weight percent sodium carbonate. The regenerating solution is created using pellets in a conventional manner in the same way that sodium chloride pellets are use to create brine solution in a more conventional water softening system.