A semiconductor device which includes: a semiconductor chip bonded to a surface of a solid device; and a stiffener surrounding the periphery of the semiconductor chip. A surface of the stiffener opposite from the solid device is generally flush with a surface of the semiconductor chip opposite from the solid device.

1. Field of the Invention
The present invention relates to a semiconductor device constructed such that a semiconductor chip is bonded to a surface of a solid device such as a wiring board or a second semiconductor chip.
2. Description of Related Art
Semiconductor devices of a flip chip bonding structure are hitherto known which, for example, have a semiconductor chip bonded to a surface of a wiring board with its face down. In such a flip-chip semiconductor device, the semiconductor chip is bonded to the wiring board with an active surface thereof being opposed to the wiring board. The semiconductor chip is physically and electrically connected to the wiring board in a predetermined spaced relation by a plurality of bumps provided between the semiconductor chip and the wiring board. Solder balls are provided as terminals for external connection on a rear surface of the wiring board. Where the number of the terminals are relatively great, the wiring board has a greater size than the semiconductor chip as viewed in plan. Therefore, a metal stiffener is provided as surrounding the periphery of the semiconductor chip to keep the planarity of the wiring board.
The semiconductor device having the aforesaid construction is fabricated, for example, by first bonding the semiconductor chip onto the wiring board and then providing the stiffener (which is a separate member from the semiconductor chip) on the wiring board. Therefore, the semiconductor chip and the stiffener, if each having a small thickness, are liable to be cracked or chipped during handling thereof for mounting thereof on the wiring board. This poses limitations to thickness reduction of the semiconductor chip and the stiffener and, hence, to thickness reduction of the entire semiconductor device.
It is an object of the present invention to provide a semiconductor device constructed so that fabrication thereof can be achieved without cracking and chipping of a semiconductor chip or a stiffener.
It is another object of the present invention to provide a fabrication process for a thin semiconductor device, which is free from cracking and chipping of a semiconductor chip and a stiffener.
The semiconductor device according to the present invention comprises: a semiconductor chip bonded to a surface of a solid device; and a stiffener surrounding the periphery of the semiconductor chip with a surface thereof opposite from the solid device being generally flush with a surface of the semiconductor chip opposite from the solid device.
The solid device may be a wiring board or a second semiconductor chip which is different from the semiconductor chip.
In accordance with the present invention, the stiffener which may be formed of a synthetic resin is provided around the semiconductor chip, whereby the solid device can be strengthened and prevented from being warped due to thermal stress.
In some cases, a heatsink plate for dissipating heat from the semiconductor chip is provided on the surface of the semiconductor chip opposite from the solid device. Even in such a case, the heatsink plate can easily be provided in contact with the surface of the semiconductor chip opposite from the solid device and the surface of the stiffener opposite from the solid device which are generally flush with each other.
Since the surface of the semiconductor chip opposite from the solid device is generally flush with the surface of the stiffener opposite from the solid device, a production serial number and the like can be inscribed across the flush surfaces. Even if the semiconductor chip has a small size as viewed in plan, a sufficient space can be provided for the inscription.
Where a plurality of inventive semiconductor devices are mounted in a stacked relation on a mounting board, a heightwise integration density can be increased because the semiconductor devices each have a smaller thickness.
The surface of the semiconductor chip opposite from the solid device and the surface of the stiffener opposite from the solid device are preferably mirror-finished surfaces. When the semiconductor device is mounted on a mounting board under monitoring with a camera, for example, the camera can recognize the semiconductor device with an improved accuracy because diffused light reflection on the semiconductor chip and the stiffener is suppressed. Therefore, the semiconductor device can accurately be positioned at a desired mounting position on the mounting board. The mirror-finished surfaces each have an increased surface strength, so that the warp of the semiconductor device can more effectively be prevented which may otherwise occur due to thermal expansion.
The semiconductor chip may be bonded to the solid device with an active surface thereof being opposed to the solid device. In this case, the semiconductor device is fabricated through a fabrication process which, for example, includes the steps of: bonding a semiconductor chip to a surface of a solid device with an active surface of the semiconductor chip being opposed to the solid device; providing a synthetic resin material to surround the periphery of the semiconductor chip with the synthetic resin material; and simultaneously planarizing the semiconductor chip bonded to the surface of the solid device and the synthetic resin material provided around the semiconductor chip after the resin provision step, so that a surface of the semiconductor chip opposite from the active surface is generally flush with a surface of the synthetic resin material opposite from the solid device.
In this process, the semiconductor chip and the synthetic resin material (stiffener) which initially each have a relatively great thickness are first provided on the surface of the solid device, and then subjected to the planarization for thickness reduction. Therefore, there is no possibility that the semiconductor chip and the stiffener suffer from cracking and chipping, unlike a process in which a thin semiconductor chip and a thin stiffener are provided on the surface of the solid device.
Even if a polishing or grinding process with the use of a grinder or a CMP (chemical mechanical polishing) process is employed for the planarization, a stress exerted on the semiconductor chip can be alleviated by simultaneously polishing or grinding the semiconductor chip and the synthetic resin material. Therefore, the warp and chipping of the semiconductor chip can be prevented.
The semiconductor chip may be spaced from the stiffener. With this arrangement, a space provided between the semiconductor chip and the stiffener can accommodate a difference in thermal expansion between the semiconductor chip and the stiffener even if the semiconductor device is exposed to a high temperature. Therefore, the warp of the semiconductor device can more effectively be prevented which may otherwise occur due to the thermal expansion.
A low elasticity filler having a lower elasticity than the stiffener may be filled in a space defined between the surface of the solid device and the surface of the semiconductor chip opposed to the solid device. With this arrangement, the active surface of the semiconductor chip can be protected by the low elasticity filler filled in the space between the surface of the solid device and the surface of the semiconductor chip opposed to the solid device. Where the semiconductor chip is supported by bumps provided between the solid device and the semiconductor chip with the active surface thereof being opposed to the surface of the solid device, stresses exerted on the bumps can be alleviated by the low elasticity filler.
The foregoing and other objects, features and effects of the present invention will become more apparent from the following description of the preferred embodiments with reference to the attached drawings.

Semiconductor device and fabrication process thereof


A new quickly replaceable electrode assembly for electroporation that also provides the functions of a pipette, capable of sucking up samples; applying extremely high electric field strength to samples at lower, safer voltages due to close spacing of the electrode plates; and expelling samples quickly and completely; along with a quick-connect receptacle for the electrode assembly. New methods are detailed for construction of electrode assemblies, providing electric current, monitoring characteristics of electric pulses delivered to samples, and space saving hand held units using low voltage D.C., A.C. line, and piezoelectric power supplies, with peak current delivered indicators are disclosed.

A wide variety of important procedures in biological research and biotechnology involve getting certain materials in to and out from cells. These procedures include gene cloning, DNA library construction, cell fusion, production of cloned proteins, tests on the effects of inserting certain materials into cells, and collection of certain materials found inside cells. Furthermore, these procedures must often be carried out on a large number of independent samples which must not be cross-contaminated. Electroporation, the transient formation of small holes in dielectrics in response to electric fields, provides a means of perforating the cell membrane for accomplishing these procedures (Neumann et al., 1982, EMBO J. 1:841-845).
Prior art electroporation equipment is comprised of large high voltage power supplies capable of producing substantial current at up to 2500 volts, such as that disclosed by Ragsdale on Jun. 7, 1988 in U.S. Pat. No. 4,750,100. Power supplies generating various waveforms, including rectangular, unipolar, bipolar, exponential decay, and radio frequency, are attached via a switching and/or timing means to a sample chamber in which electrodes are spaced to give a field strength appropriate to form pores in the cells of interest (Tekle et al., 1991, PNAS. 88:4230-4234). Existing devices such as that disclosed in U.S. Pat. No. 4,800,163 by Hibi et al. in 1989, are large, expensive, complex, and are more efficient for bulk industrial processing than for the processing of the dozens of individual samples more common in research laboratory work. In working with such samples, which must not be cross-contaminated, it is necessary to replace the electrode assembly with a clean, sterile electrode assembly before each sample is processed. It is an object of the present invention to provide an economical, easily and quickly replaceable, electrode assembly and associated apparatus especially well suited for research laboratory use. Because of the potentially lethal voltage/current combination, sample chambers are usually hidden in protective enclosures with safety interlocks to keep the user at a distance from the high voltage. While such an apparatus provides a reliable means of delivering voltage to a sample, it occupies considerable space and requires complex and time-consuming manipulations to insert and remove samples. Aside from the tedium and high labor cost, there is another significant problem with the prior art apparatus. As described by Dower in U.S. Pat. No. 4,910,140, Electroporation of Prokaryotic Cells, on Mar. 20, 1990, the efficiency of recovering live cells containing molecules of interest falls rapidly as time increases.
The improvements to electroporation of the present invention eliminate the tedium of a human operator as well as increase the survival of electroporated samples due to reduced time under hostile conditions. Some prior art instruments provide numerical feedback relating to current, voltage and wave shape parameters of the delivered energy. The present invention simplifies operation by providing go/no go indicator lights instead of confusing numerical information.
Because only brief pulses of high current are required, a number of options other than the typical bulky continuous duty high voltage power supply are disclosed. In the preferred embodiment of the present invention, a small Direct Current inverter type transformer is used in "flyback" mode to store charge in a capacitor for subsequent discharge. In electrotransfection experiments with E. coli bacteria, efficient transformation was observed using Alternating Current sources including 120 volt 60 hertz line power. Therefore an alternate embodiment of the present invention eliminates the high voltage supply altogether and substitutes the timed application of A.C. line current directly to the sample. The rapid mechanical deformation of piezo-electric crystals provides a high voltage pulse. Therefore in a third embodiment of the present invention the high voltage power supply is comprised of a piezo-electric crystal and mechanical trigger. Because of the electrode assembly's pipetting feature in the present invention, electrodes can advantageously be spaced more closely than in prior electroporation equipment, thus lower voltages can be employed to achieve the desired field strength. This invention provides a system more compact and safe, yet much less complicated and expensive than other systems, for example U.S. Pat. No. 4,750,100 mentioned above.

Improvements to apparatus and method for electroporation


A low profile antenna having relatively high radiation resistance, wide bandwidth and which utilizes a single conductor and RF source is disclosed. In accordance with an exemplary embodiment, the upper horizontal portion and the lower horizontal portion of the double inverted-L antenna are respectively brought down and up (without being physically connected) at a distance of approximately 180 degrees (½λ) from the RF source so as to form two additional vertical portions of the antenna. This is followed by two approximately 90-degree (¼λ) horizontal conductors portion. The resulting radiation resistance of the low profile antenna is approximately three-times that of a double inverted-L antenna.

As circuit size decreases in many mobile communications devices, and associated plastics housings and the like reduce in size, mobile radio handsets are also decreasing in size. One item of a radio communications device which cannot easily be reduced in size, however, is the antenna. Typically the antenna is one half or one quarter of a wavelength in length along at least one axis and as such cannot easily be reduced.
An antenna radiates electromagnetic waves when there is an acceleration of charge through the conductor. This produces a magnetic field, which then produces electromagnetic (EM) radiation. One type of antenna known to those skilled in the art is the resonant dipole antenna 100, depicted at FIG. 1. A radio frequency (RF) source 120 is depicted at the center of the conductor 110 for providing an RF signal resonating at a given frequency (e.g., 5 GHz). The conductor extends out from either end of RF source 120 by ¼ wavelength (¼ λ).
The magnitude of the instantaneous current flowing through the conductor is depicted by the curved line to the right of the antenna. As depicted, the current flow is at a maximum at the center of the conductor 110 and gradually reduces as the ends of the conductor 110 are approached. The circles depict the direction of the magnetic field produced by a current flowing in the upward direction. The magnetic fields for the upper and lower halves of the conductor 110 are depicted as being in the same direction. This signifies that the EM radiation from each half is in phase.
Turning to FIG. 2, the dipole antenna of FIG. 1 is depicted as being bent in half to reduce its vertical profile. The FIG. 2 antenna 200 is known in the art as a double inverted-L antenna. Here, the antenna 200 resonates at the same frequency (e.g., 5 GHz) as the FIG. 1 dipole antenna 100, and the current magnitude remains unchanged from that of the FIG. 1 antenna 100. The main difference between the FIG. 2 antenna 200 and the FIG. 1 antenna 100 is that the magnetic fields produced by the two horizontal portions 220, 230 are now 180-degrees out-of-phase and cancel each other out. As a result, there is virtually no EM radiation from the horizontal portions 220, 230 of the antenna 200; only the vertical portion 210 radiates, thereby greatly reducing the radiation resistance of the antenna 200 from that of the FIG. 1 dipole antenna 100. A reduced radiation resistance translates to the need for a higher antenna current to radiate the same RF energy. Accordingly, there is a need in the field of radio communications for a low profile antenna designed to provide a vertically short profile while exhibiting a relatively high radiation resistance, wide bandwidth, and gain over a simple short conductor.


A process for implementing logic units using base cells and implementing an electrical connection between the logic units in a gate array. The process includes determining a connection path between the base cells and connecting the base cells at the second metalization layer using a portion of the first metalization layer. This is possible due to the gate array having vertical first metalization layer segments of the first metalization layer positioned vertically in the channel between the rows of base cells, wherein each of the vertical segments has vias in the insulation layer between the first metalization layer and the second metalization layer at its endpoints for connecting the metalization layers. Similarly, the individual transistors which comprise the base cell are coupled using the second metalization layer to implement a specific logic unit.

Typically integrated circuits (ICs) are manufactured through the manipulation of photographic masks. Today, custom logic can be built on an IC that contains an array of transistors with programmable interconnections. These are referred to as gate arrays. The logic of the transistors and the interconnect are configurable based on the user's needs. The architecture of these gate arrays consists of rows (columns) of transistors separated by a distance that is used to connect the rows (columns) together. The space between the rows is also used to bring connections to the I/O logic which is usually around the periphery of the IC.
A fully customizable IC consists of many layers. A typical gate array has some number of base layers required to build the transistors, with the top four layers of the IC being programmable. The four programmable layers are used to define the logic function of the array of transistors as well as provide the interconnect between the defined logic functions.
FIG. 1 shows a device, usually a transistor, fabricated as p-channel metal-oxide semiconductor (PMOS) transistor 100. The fabrication of PMOS transistor 100 involves a series of steps. Referring to FIG. 1, PMOS transistor 100 consists of substrate 101 which is doped with n.sup.+. The n.sup.+ doping indicates a heavily doped substrate. Diffused into substrate 101 are two p.sup.+ regions 102 and 103. These are typically implanted using ion-beam technology. Once again, the p.sup.+ designation indicates a strong doping of p carriers. An oxide layer 105 is created on top of the n.sup.+ region 101 between p.sup.+ regions 102 and 103. A polysilicon (Si) layer 104 is built on the oxide layer 105. An insulation layer 109 is grown over substrate 101. The polysilicon layer 104 and p.sup.+ regions 102 and 103 represent the three parts of a transistor device.
To create the transistor device, PMOS transistor 100, p.sup.+ regions 102 and 103 and polysilicon 104 are connected. The connection to the device occurs using contacts (i.e., holes) 106, 107, and 108. These contacts are connected to a first metalization layer 110. First metalization layer 110 could be aluminum. An insulation layer, oxide 111, is fabricated over metalization layer 110. Holes, known as vias, are created in insulation layer 111. The vias are formed using well-known mask technology, wherein a photographic process, in conjunction with an etchant, creates a hole. Next, a second metalization layer 113, is placed over insulation layer 111. In fabricating metalization layer 113, metal flows into the vias and connects to metalization layer 110. Vias are shown as 112a, 112b and 112c in FIG. 1. Finally, an insulation layer, oxide 114, covers the entire wafer, including PMOS transistor 100, to complete the fabrication process. NMOS transistors are built similarly but with opposite dopings.
As described above with respect to FIG. 1, logic units are formed by coupling multiple transistors together. Each logic unit can perform a different logic function. Thus, custom logic can be built by connecting individual logic functions together. In gate arrays, rows of same sized transistors are created and equally spaced apart. To customize the logic, sets of transistors are then connected together to form a logic unit and the logic units are connected through the spacing, i.e. channel, between the rows of transistors (which are now formed into logic units). Usually, a minimum set of transistors, possibly two PMOS and two NMOS, is required to create a logic function. This minimum set is known as a base cell. A logic unit may consist of one or more base cells.
To create the logic units, known as personalizing the transistors or base cells, and the connections, a place and route software chooses the location of the logic units and how they are to be connected. To electrically create and connect the logic units, the wafer is processed using the four steps referenced above (contact, first metalization, via, second metalization). This entire process is known as "personalizing the gate array." To complete these steps, four separate masking steps are required, one for each processing step. The personalization and connection of the units is performed using both metalizations and their corresponding interconnections. A common routing technique would utilize the first metalization for portions of the path which run vertically between the rows, i.e. in the channel space, and use the second metalization for the portions of the path that run horizontally through the channel space. The first and second metalizations are coupled with vias. This allows a path to avoid collisions with other paths since all horizontal runs are insulated from vertical runs.
The problem with the prior art is that four stages of fabrication are required to create custom logic. Each stage requires four separate masks and a considerable amount of time. Furthermore, if a problem occurs in the fabrication of any of the stages, the entire process must be repeated.
The present invention avoids these problems of customizing integrated circuits by utilizing gate arrays which are fabricated up to the last metal layer (i.e., the second metalization layer) and personalizing and connecting base cells to form logic units in the array at the second metalization layer using portions of the first metalization layer. This allows for a faster turn-around time for creating the custom chip and better reliability.

Method of making single layer personalization


An image display apparatus includes a plurality of line cathodes arranged horizontally in parallel with each other; an electron beam leading electrode device allowing a plurality of electron beams radiated from the line cathodes to pass therethrough; a signal electrode device for controlling quantity of the electron beams passing therethrough according to a video signal; a focusing electrode device for focusing the electron beams; a horizontal deflecting eletrode device for electrostatically deflecting the electron beams horizontally; a vertical deflecting electrode device, for electrostatically deflcting the electron beams vertically, comprising of a pair of comblike conductive plates each having vertical teeth spaced to intervals, opposed to each other, and alternating with each other in the same plane, electron beams which pass through the vertical deflecting electrode device crossing over in a vertical section thereof and being focused; and a display device which emits a light as a result of a collison of electron beams.

1. Field of the Invention
The present invention relates to a method of controlling electron beams in an image display apparatus for use in a video equipment.
2. Description of the Related Art
Conventionally, a cathode-ray tube is mainly used as the image display element of a color television, however, the cathode-ray tube is much greater than the screen in depth. Therefore, it is impossible to manufacture a thin television receiver. In order to manufacture a thin television receiver, display elements such as an EL display element, a plasma display element, and a liquid crystal display element have been developed. But none of them are preferable in luminance, contrast, and a color reproducibility.
In order to solve the above-described problem, the following image display apparatus of a color television has been developed. The image plane thereof is divided into a plurality of sections of a matrix configuration so that a thin and flat device displays an image utilizing electron beams which form an image equal to that of the cathode-ray tube in quality. Each section is scanned by deflected electron beams so that a fluorescent substance emits a light.
The above-described conventional image display apparatus is described in detail with reference to the drawings.
Referring to FIG. 2 showing the inner construction of the image display apparatus, it comprises a backplate 1; a line cathode 2 serving as an electron beam source; a leading electrode 3; a signal electrode 4; a focusing electrode 5; horizontal deflecting electrodes 6a and 6b; vertical deflecting electrodes 7a and 7b; and vacuum glass containers 8a and 8b accommodating the above components.
Describing the outline of this apparatus, a plurality of rows of electron beams generated by the line cathode 2 are horizontally sequentially introduced through the through-holes of the leading electrode 3. The electron beams are sequentially controlled by the signal electrode 4 according to a video signal. Then, the electron beams are electrostatically focused by the focusing electrode 5, and then, electrostatically deflected horizontally by the horizontal deflecting electrodes 6a and 6b and vertically by the vertical deflecting electrodes 7a and 7b. A section 11 of a screen 10 is scanned by one electron beam 9. All sections 11 are connected to each other without any gap therebetween to form an entire image on the screen 10. These electrodes consist of a thin conductive plate and can be laminated with each other.
Therefore, compared with a cathode-ray tube, a thin image display apparatus can be manufactured.
However, in the above conventional image display apparatus, the diameters of electron beams composing a small image plane of a matrix configuration are different from each other in the vertical sections thereof. Thus, the difference in spot diameters does not ensure the uniformity of the image formed on the screen 10. This phenomenon is described with reference to FIG. 3 which is a vertical sectional view showing one electron beam generated by one of the line cathodes 2 of the conventional image display apparatus shown in FIG. 2. The electron beam is electrostatically deflected by the potential difference between the vertical deflecting electrodes 7a and 7b to form trajectories 20 and 21, thus reaching the screen 10. As a result, beam spots 22 and 23 are formed on the screen 10. But when the electron beam is electrostatically deflected, deflection errors (coma) occur because the diameter (d) thereof is great when it passes through the vertical deflecting electrodes 7a and 7b. As a result, compared with the beam spot 22 formed when a deflection amount is small in the vertical direction, the beam spot 23 formed when a deflection error (coma) is great in the vertical direction is not focused. Therefore, the beam spot 23 is vertically elongated or trailed upward. Spots in different configurations appear in succession horizontally on the screen 10. Therefore, when an entire image is viewed, long and narrow non-uniformities having different luminances are observed, thus damaging the uniformity of the image.

Method of controlling electron beams in an image display apparatus

Matsushita Electric Industrial Co., Ltd.


A pre-stretch wrapping device consisting of a base, a pre-stretch station, a vertical drive, and a rotatable load causes a pre-stretched web to become wrapped around the load under controlled tension. The pre-stretch station comprises a pair of pre-stretch rollers located on a pivotal frame, a spring which opposes the pivotal movement of the frame relative to the base, a roller motor, and a sensor located between the frame and the base. The sensor monitors relative movement of the frame from the base and a controller in response to signals from the sensor controls the operation of the roller motor.

The transportation of multiple sacks or boxes is commonly simplified by stacking them in an ordered manner on a platform, usually referred to as a pallet. This pallet, normally made of wood or plastic, can then be lifted and carried by a forklift and thereby stored in a warehouse or placed in a mobile transport, such as cargo ships or trucks. Such loading and transport arrangements can undesirably result in knocking the sacks or boxes off their pallet. In order to stabilize the load on the pallet, a film or web is commonly wrapped around the stacked items. It is desirable to pre-stretch this web past its elastic limit during the wrapping operation, in order to bind the pallet load as tightly as possible.
There are numerous prior art packaging devices available to generate the forces required to stretch and wrap a plastic web around an arbitrarily shaped pallet load. The more recent devices, such as U.S. Pat. Nos. 4,458,467 and 4,706,443, use a set of pre-stretch rollers which stretch the plastic web by a predetermined amount without putting an excessive or uneven horizontal destabilizing force on the pallet load. The tension of the prestretched web is controlled by monitoring movement of the idler rollers. The pre-stretch process also has the added benefit of smoothing out any unnecessary wrinkles present in the feedstock wrapping material.
One disadvantage of this wrapping process is the tension on the pre-stretched wrapping material does not usually remain constant while it is being applied to the pallet load. The exterior load surface is typically at varying radial distance from the load center and the load rotates in an eccentric manner because of unavoidable inexact centering on the turntable. The resulting variability in wrapping tension may produce tight and loose regions in the wrap, which can cause the wrapped load to be become unstable. There is a need to retain a predetermined web tension during wrapping so as to bind the load tightly, but the nature of the load results in a need for adjusting the web speed.
The two above mentioned prior art devices compensate for the variability in web tension by changing the speed of the roller-motor through a feedback sensor and controller system. This is accomplished in the case of 4,458,467 through the use of two idler rollers and a position transducer, which senses excessive rotational displacement of the idler assembly from its biased position. Reduction of one idler roller was accomplished by 4,706,443 but with the added consequence of a more complicated position sensor arrangement.
The use of idler rollers for feedback control compensates for the problem of variable pre-stretched web tension, but also increases the tortuosity of the path the fragile web must travel from the pre-stretch rollers to the pallet load. This increases the risk of damage to the thin pre-stretched web during the wrapping operation, which normally takes place in an industrial environment. The increase in path length for the pre-stretched web also allows the applied pre-stretch additional recovery time, which is not desirable because either the web must be over-stretched to compensate for the recovery period, or the binding strength of the wrapped web around the pallet load can be less than optimal. An additional complication is the increase in the size of the packaging device's footprint, which is undesirable in small spaces and high traffic areas. One further disadvantage of employing idler rollers to control web tension is the increased weight of the pre-stretch assembly, which must be raised and lowered throughout the wrapping operation by mechanized means.
It is an object of the present invention to obviate or mitigate the above problems.


A method for catalyzing the trimerization of an isocyanate and/or the reaction between an isocyanate and an active hydrogen-containing compound, the improvement which comprises employing a catalyst composition consisting essentially of the addition product of a tertiary amine urethane catalyst and a boron compound of the formula EQU R.sub.n BX.sub.3-n. where. n represents 0, 1, 2 or 3, PA1 X represents F, Cl, Br, OCOR', OR" or mixtures thereof, and PA1 R, R' and R" independently represent C.sub.1 -C.sub.8 alkyl, C.sub.5 -C.sub.8 PA1 cycloalkyl, C.sub.6 -C.sub.10 aryl or mixtures thereof.

In the production of polyurethanes, it is often desirable to control the activity of the catalyst(s). The effect of controlled catalysis may be realized in improved reactivity profiles, for instance delayed initiation or accelerated cure. Such reaction rate control is of particular importance to the polyurethane molder, where it is important that the polyisocyanate/polyol mixture remain flowable for sufficient time to fill the mold properly, while maintaining or improving demold time. Controlled catalysis can also affect product distributions and significantly impact physical properties of the final polyurethane part.
Latent activity catalysts for initiation delay in polyurethane systems have been reported in the literature. One solution has been the use of ammonium salts of carboxylic acids, alone or in combination with other organometallic catalysts. The disadvantage of such materials is mainly their corrosiveness, but poor polyol masterbatch stability has also been reported in the presence of these acid blocked amine catalysts in U.S. Pat. No. 4,707,501. Bronsted acid blocked amine catalysts are prepared by reaction of a tertiary amine with a glycol borate acid. U.S. Pat. Nos. 3,193,515; 3,127,404 and FR 2,301,554 disclose the use of boric acid in the preparation of a blocked amine catalyst from triethylenediamine and a glycol borate acid. An ammonium salt of a quaternary borate anion results. The advantage of such catalyst composition is delayed activity and/or accelerated cure.
U.S. Pat. No. 5,086,081 describes reduced odor amine-boron compositions prepared from tertiary amine urethane catalysts and boric acid. These compositions are of reduced viscosity, low corrosiveness and impart improved reactivity profiles and physical properties during the production of polyurethane parts. These patents also mention the use of functional equivalents to boric acid (e.g., borate esters such as alkyl, dialkyl and trialkylborates in which the alkoxy groups hydrolyze to hydroxyl functionality in the presence of water).
Quaternary ammonium borates have been used to effect the concurrent trimerization/carbodiimidization of polyisocyanates (U.S. Pat. No. 4,611,013). The borates are prepared from boric acid, alcohols and quaternary ammonium hydroxide and, as such, are not derived from tertiary amines. Other examples of quaternary borate anions as polyurethane catalysts are given in U.S. Pat. Nos. 4,151,334; 3,697,485 and 3,635,848. Borate anions derived from borate esters have also been used for the production of isocyanurate and carbodiimide-isocyanurate foams. These borate anions are prepared by reaction of an alcohol with a borate ester (or boric acid) in the presence of an alkali metal.
The formation of amine-borate complexes has been reported in the literature and appears to depend on both steric and electronic factors. The trialkylborate formed from boric acid and nitrilotriethanol shows no reactivity toward moderate nitrogen nucleophiles, such as diazabicyclo[2.2.2]octane, whereas the related borate formed from 2,2',2"-nitrilotriphenol and boric acid was found to form an adduct with diazabicyclo[2.2.2]octane and other amines (Helv. Chim Acta 1987, 70, 499). Pyridine forms a 1:1 complex with tris-p-chlorophenylborate yet does not react with tris-2,4,6-trichlorophenylborate or 2,6-dimethylphenylborate (J.Chem. Soc. 1956, 3006).
Although acyl borates are known, e.g., boron tris(trifluoroacetate) (Fieser and Fieser 4, 46 and 5, 55), the use of acyl borate-amine complexes as urethane catalysts has not been investigated.
Boron halides are known to form stable complexes with amines. An example would be boron trifluoride-ethylamine (Beil. 4(2), 588). Such materials are well known epoxy curatives and have been used in formulations containing both polyisocyanates and polyepoxides (examples are U.S. Pat. Nos. 4,698,408 and 3,986,991).

Amine-borate and amine-boron halide complexes as catalyst compositions for the production of polyurethanes


The disclosed embodiments include a system, computer program product, and computer-implemented method configured to modify a knowledge graph. The disclosed embodiments seek to improve the process of expanding a knowledge graph by identifying information that is useful and relevant to the needs of the users based on questions being asked by users. In one embodiment, the information is collected using a gaming platform. The disclosed embodiments augment the knowledge graph, by adding new entities and/or relationships, based on the gathered information.

The present disclosure relates generally to the field of semantic queries. Semantic queries enable the retrieval of both explicitly and implicitly derived information based on syntactic, semantic and structural information contained in data. Semantic queries often involve the use of a knowledge base. A knowledge base may store complex structured and unstructured information used by a computer system. A knowledge graph depicts the relationship between various entities contained in the knowledge base.

Crowdsourced discovery of paths in a knowledge graph

INTERNATIONAL BUSINESS MACHINES CORPORATION


In an image forming apparatus wherein a multiple number of image supports form developer images of different colors so that the developer images of different colors corresponding to the multiple number of image supports are superimposed to a recording medium to form an image, flywheels are set at the ends of the rotary shafts of multiple image supports corresponding to relatively highly visible colors while no flywheel or a flywheel having a different diameter or weight from that of the above is set for the image support corresponding to a less visible color so as to make the inertial condition different from that of the others.

(1) Field of the Invention
The present invention belongs to the technical field of image forming apparatus in which an image is formed by conveying a predetermined recording medium along a plurality of image supports arranged in parallel to each other so as to sequentially and superimposingly transfer the developed images on individual image supports to the recording medium. More detailedly, the present invention relates to an image forming apparatus of the so-called tandem type having a plurality of image supports each having a rotational inertial body such as a flywheel or the like at one end of their rotary shafts.
(2) Description of the Prior Art
In general, in conventional image forming apparatus for recording designated image information by performing line-wise scanning such as laser scanning on an image support such as a phtoreceptor, drive irregularity occurs in the driving mechanism for rotating the image support. When an image of lines is recorded, this drive irregularity will cause image unevenness (so-called banding) which is made up of bands in the final image on the recording medium.
In order to solve the above problem, a rotating inertial body such as a flywheel has been provided at one end of the rotary shaft of the image support. That is, in an attempt to reduce the drive irregularity originating from the driving mechanism, a heavy, rotating inertial body has been provided to produce the desired inertia for the rotation of the image support.
On the other hand, in the field of image forming apparatus, there has been a development towards multil-colorization of recorded images. A known typical example of color image forming apparatus is the so-called tandem type having multiple image supports therein. In such a color image forming apparatus, when a developed image of a relatively more visible color on the image support deviates from the correct position due to drive irregularity, color blur occurs in each developed image even if the deviation is slight. Therefore, it is necessary to establish rotational synchronism between individual image supports, so that rotational inertial bodies of an identical type need to be provided for all the multiple, image supports in order to take into account the rotational drive irregularity of the image supports.
Accordingly, in an image forming apparatus having multiple image supports, provision of rotational inertial bodies of an identical type for all the multiple image supports increases the number of assembly parts, hence causing various problems including: lowering of design flexibility, increase in the manufacturing cost, making the apparatus bulky hence the needing of a large space for installation, and increase in the machine weight hence rise in the cost for transportation.
Japanese Patent Application Laid-Open Hei 4 No.147279 has proposed a technique that reliably establishes synchronized rotations of all the image supports in an image forming apparatus of the so-called tandem type while preventing bulkiness of the apparatus. That is, in this configuration, the rotational inertial bodies are made up of an non-circular shape having the same inertia and attached on the rotational shafts of all the image supports to thereby reduce the distance between image supports.
As above, in the tandem type, image forming apparatus of Japanese Patent Application Laid-Open Hei 4 No.147279, the rotational inertial bodies provided on the rotational shafts of all the image supports, have the same, non-circular sectional feature in order to equally increase the inertia of all the image supports, whereby it is possible to reduce the distance between image supports, and hence this configuration contributes to securing reliable synchronized rotations of multiple image supports whilst minimizing the size of the image forming apparatus.
It is true that the technology described above can shorten the distance between image supports and inhibit the bulkiness of the apparatus as a whole, compared to the conventional configuration where circular rotational inertial bodies are arranged in parallel, but it still suffers from unsolved problems of increase in the manufacturing cost and apparatus weight due to increase in the number of assembly parts since the rotational inertial bodies of the same type are needed for all the image supports. Further, this configuration is limited by the complex shape of the rotational inertial bodies and their arrangement and also by the necessity of a control means and the like for exactly controlling the rotational positions of the rotational inertial bodies so as not to interfere with each other. Thus, there are sill unsolved problems such that design flexibility is markedly hindered.

Image forming apparatus with different inertial conditions among image supports


An absolute position measurement capacitive grating displacement measurement method, a sensor, and an operating method of the sensor are provided. In the measurement method, a drive signal having wave properties is used to excite a transmission grating, and displacement of a measured position in each wavelength is transformed into an initial phase of a time fundamental wave. The displacement of the measured position in each wavelength is acquired through an addition counter. A signal having wave properties output by a drive signal generator of the sensor is connected to a transmission grating, the master clock of an oscillator is connected to each circuit, an output of a reception grating is connected to a synchronous capture circuit through a signal selection switch and an analog processing circuit; and the synchronous capture circuit is connected to a controller, an addition counter, and a Random Access Memory (RAM). The controller is connected to all components. In the operating method of the sensor, an interface unit starts a measurement unit, a controller coordinates operation of all circuits, and after measurement of displacements in coarse, medium, and fine wavelengths is successively completed, the interface unit turns off the measurement unit, performs processing, and displays the measurement result. The circuits are simple, easy to control, and easy to be realized, and have high precision.

1. Field of the Invention
The present invention relates to the capacitive displacement measurement technology, and more particularly to an absolute position measurement capacitive grating displacement measurement method, a sensor, and an operating method thereof.
2. Related Art
A capacitive grating displacement sensor is widely applied in the fields of linear/angular displacement measurement due to the characteristics thereof such as a low cost, a small size, and low power consumption. In terms of the realization principle, current capacitive grating displacement sensors are categorized into relative position measurement (an incremental type) capacitive grating displacement sensors and absolute position measurement (an absolute type) capacitive grating displacement sensors. The incremental type capacitive grating displacement sensor has been applied for about thirty years, and in this kind of sensors, a displacement amount needs to be rapidly accumulated, resulting in two defects: a measurement speed limit (lower than 1.5 m/s @150 KHz) and uninterruptible measurement (so further decrease of a working current is limited), such that the incremental type capacitive grating displacement sensor is gradually phased out. The absolute type capacitive grating displacement sensor is initiated by a Japanese company named Mitutoyo, and the implementation method thereof may be referred to patents CN89106051, U.S. Pat. No. 5,053,715, CN92101246, and CN93117701. This kind of sensor uses two or more code channels (wavelengths) to perform absolute positioning, so the requirement for rapid accumulation of a displacement amount is eliminated, and the work is in an intermittent measurement state (approximately 8 times per second), thereby overcoming the main defects of the incremental measurement. However, the existing absolute type capacitive grating displacement sensor has the following defects.
1. A sensor drive signal is a static (irrelevant to time) and spatially distributed waveform. A demodulated received signal is irrelevant to time (a direct current (DC) signal), and a harmonic effect cannot be alleviated through signal processing technologies.
2. In order to downsize a harmonic component, a sine waveform electrode that is difficult to make is required to be used.
3. Analog-to-digital (A/D) conversion of two orthogonal signals is required to be performed to determine a displacement amount in each wavelength.
4. An arctg operation is required to be performed to determine a displacement amount in each wavelength, which exceeds a real-time processing capability of a common Micro Controller Unit (MCU). In order to reduce a processing load of the MCU, linear approximation has to be adopted.
5. In order to reduce a linear approximation error, a sensor drive signal is required to be probed repeatedly to make a received signal close to a zero point.
6. In order to reduce the linear approximation error and a harmonic component effect, a relatively small fine wavelength (1.024 mm when the resolution is 0.01 mm) is required to be used.
7. The determination of the displacement amounts in all wavelengths hampers and influences each other, and during rapid movement, the algorithm does not converge.
In conclusion, the existing absolute type capacitive grating displacement sensor requires an MCU to be a core, software is based on an inefficient probing method, and peripheries require support of technologies such as complicated A/D conversion and a sine waveform electrode. Although a regular Single Chip Microcomputer (SCM) can indeed meet the aforementioned requirements on software and hardware, it is not easy to integrally install the system (made into a single-chip Application-Specific Integrated Circuit (ASIC)) on a handheld measurement tool to obtain a product that has a low cost, a small volume, low power consumption, and is suitable for mass production at the same time.
Patent ZL200710050658 introduces a round grating sensor for absolute position measurement, and the patented solution is applicable to angle measurement in a large distributed space. But an SCM is used for performing secondary processing on measurement results of two independent incremental type capacitive grating systems, which makes the cost, size, and power consumption several times as those of a normal incremental type capacitive grating system. Although functions of the incremental type capacitive grating system are extended, but inherent defects of the incremental type measurement are not solved.

Absolute position measurement capacitive grating displacement measurement method, sensor, and operating method thereof


Tantalum powder obtained by adding magnesium powder to tantalum powder which is prepared by reducing potassium tantalum fluoride with sodium metal, without conventional heat-treatment for agglomeration, to remove oxygen present in the tantalum powder, then washing with an acid and drying; an anode body for electrolytic capacitors produced by sintering the tantalum powder; and, an electrolytic capacitor which comprises the anode body incorporated therein. The tantalum powder has a large specific surface area and accordingly, the electrolytic capacitor in which the anode body produced from the tantalum powder is incorporated has an extra high capacity, i.e., a CV ranging from 70000 to 80000. The probability of causing ignition during the production process is substantially reduced and thus the tantalum powder can be handled with safety.

The present invention relates to tantalum powder useful as a material for electrolytic capacitors, an anode body for electrolytic capacitors which is prepared by sintering the tantalum powder and an electrolytic capacitor in which the anode body is incorporated.
Tantalum has been used as an electrode material for capacitor because of a high dielectric constant, on the order of about 27, of the oxidized film thereof, but there has recently been desired for the development of an electrolytic capacitor having an improved capacity for the reasons of competition with other capacitors and a general tendency toward miniaturization of electric and electronic apparatuses and correspondingly, there has rapidly increased a need for tantalum powder as such an electrode material.
Tantalum powder is in general prepared by reducing potassium tantalum fluoride with sodium. The spault-like tantalum powder thus prepared includes salts as by-products and accordingly, the tantalum powder is subjected to a treatment such as water-washing and/or acid-washing to remove the salts present therein and to thus improve the purity thereof and then dried to give raw powder. The tantalum powder prepared through reduction with sodium metal is not easily handled since it comprises fine particles having an average particle size on the order of 0.3 to 3.0 .mu.m. For this reason, tantalum powder containing fine particles is heat-treated in a vacuum to once agglomerate the powder, followed by disintegrating the agglomerate into porous particles having a particle size ranging from 1.0 to 5.0 .mu.m and a large specific surface area prior to the practical use thereof.
As has been discussed above, tantalum powder (raw powder) is heat-treated in a vacuum to remove any gaseous components (hydrogen gas) and metallic impurities (such as sodium and potassium) and to granulate the fine particles and improve the flowability of the powder. Incidentally, the content of oxygen present in the tantalum raw powder having an average particle size ranging from 0.3 to 0.4 .mu.m ranges from about 7000 to 9000 ppm, but the content thereof is increased up to a level ranging from 12000 to 14000 ppm due to the heat-treatment in a vacuum. The presence of oxygen increases the leakage current of the powder which is an important electrical property. For this reason, most of the tantalum powder products are subjected to removal of oxygen through reduction with, for instance, magnesium metal to improve the leakage current, followed by acid-washing and drying processes prior to the practical use thereof in the electrode-production.
The electrostatic capacity (C) can be expressed by the following relation: EQU Electrostatic Capacity C=Dielectric Constant (.epsilon.).times.Specific Surface Area (S).div.Film Thickness (d)
Therefore, tantalum powder to be developed and used as an electrode material for electrolytic capacitors having an extra high capacity must have a specific surface area as large as possible. For instance, it is necessary, for the development of such tantalum powder, to prepare raw powder having a large specific surface area through reduction with sodium; to prepare raw powder whose impurity content is reduced to a lowest possible level so as to cope with the requirement for the pellet-sintering temperature which has recently been inclined to be reduced; and to select the optimum temperature for the heat-treatment so that the heat-treatment is not accompanied by a substantial reduction in the specific surface area of the raw powder.
However, when preparing tantalum powder having a large specific surface area and used as an electrode material for electrolytic capacitors having an extra high capacity according to a conventional method, the following problems arise.
1 Fine tantalum particles having a large specific surface area and prepared by reduction with sodium metal are significantly sensitive to heat and have high activities. For this reason, the particles partially undergo granulation at a considerably low temperature for the heat-treatment on the order of 1200.degree. to 1300.degree. C. This granulation leads to a decrease in the specific surface area of the particles and makes the production of a capacitor having a high capacity difficult. PA1 2 The decrease in the specific surface area may be inhibited by reducing the temperature of the heat-treatment, but the degree of oxygen-pickup is increased when removing the product from a heat-treating furnace after finishing the heat-treatment in proportion to the reduction in the temperature of the heat-treatment and the risk of ignition correspondingly increases. PA1 3 Moreover, a scattering (.+-.15.degree. C.) in the temperature is observed within the furnace for the heat-treatment and accordingly, there are likewise observed scatterings in physical properties (such as specific surface area, bulk, particle size distribution) and electrical properties (such as CV). PA1 4 The ingredient must be heat-treated little by little for preventing any ignition (for reducing the quantity of accumulated heat). In addition, it is necessary to remove the product from the furnace after completion of the heat-treatment while stepwise bringing it into contact with oxygen (several steps) and, for this reason, the productivity rate thereof is substantially impaired.

Tantalum powder and electrolytic capacitor using same


In certain embodiments, a device is configured to be compressed and inserted into the distal end of an endoscope. The delivery device can be configured to deliver the delivery catheter to the site of one or more fistulas in the wall of a body cavity or lumen within a patient. The delivery catheter is configured to deliver the device to the site of the one or more fistulas. The device is configured to expand at the site of the one or more fistulas and substantially seal the fistula in one or more directions. In some embodiments, at least a portion of the device is coated with and/or constructed of biocompatible material. In some configurations, the device is configured to be implanted for an extended period of time or even permanently. In some embodiments, at least a portion of the device is constructed of biodegradable, dissolvable and/or bioabsorbable material.

Field of the Invention
The present invention relates in general to the field of pulmonary treatments, and specifically to methods of sealing fistulas and ruptures in a lung or trachea.
Description of the Related Art
Described herein are systems and methods for sealing an airway rupture or fistula to stop, reduce, and/or control leaks of lung airways that have been damaged or have a defect. Also disclosed are systems and methods for controlling a transfer of a fluid, gas and/or liquid between two spaces. One common clinical condition in which such transfer can occur is called a "stump leak" fistula.
A stump is the remnant of an airway that has been resected as close as possible to its anatomical origin. Stump leaks can occur after a surgery has been performed to remove a lobe (lobectomy) or a whole lung (pneumonectomy). During surgery, the lung tissue is resected, as well as the airways and blood vessels that feed that portion of lung tissue. Therefore, during the resection, the surgeon will attempt to cut the tissue as close as possible to its anatomical origin.
After resection, stump leaks may occur because it is sometimes difficult to cut and completely seal the large diameter airways. Another cause of a stump leak could be the dehiscence of sutures that were keeping the airway(s) closed. As a consequence, in the post-surgical phase, the defect will produce leakage of air and/or fluid into the thoracic cavity. Another cause of stump leak could be an infection in the vicinity of a sutured airway. Such an infection could degrade the tissue surrounding the suture and cause stump leaks and other fistulas to form.
Some solutions have been developed for the treatment of fistulas and ruptures of the lung and/or trachea. For example, treatment methods such as pleurodesis, the use of lasers, cryoablation, cauterization and/or the placement of packing materials into the fistula/rupture have been used. Some of these solutions, however, have significant drawbacks. For example, pleurodesis may not work in the context of pneumonectomies because there is no lung pleura to attach to the chest wall pleura. Due to the inherent limitations of many of the above treatment methods and devices, there remains a need for improvement to devices and methods for the treatment of airway fistulas and/or ruptures.

Systems and methods for treating fistulas in the lung and trachea


An injector structure is disclosed for delivering liquid additives, and particularly colorants, into a polyester production system capable of being cleaned without removal from a production line. The device includes a valve body with an internal channel extending longitudinally therein, a hollow housing for receiving a reciprocating stem, and an insulating jacket for minimizing the affect that heat from a melt extruder may have on the liquid colorant as the liquid colorant flows through the injector. A fluid inlet in communication with the internal channel is provided for delivering fluid from an external source to the valve body. The reciprocating stem, in an open position, allows liquid colorant to flow from the fluid inlet through the internal channel and out of a discharge opening at one end of the valve body. In a closed position, the reciprocating stem blocks the internal channel thereby preventing delivery of the fluid from the fluid inlet to the discharge opening. By reciprocating the stem within the internal channel, any obstructing matter is loosened, thereby allowing an uninterrupted flow of liquid colorant through the injector structure.

The textiles industry uses synthetic fibers for a wide variety of applications including clothing and other fabric items which are desirably manufactured and marketed in a variety of colors and patterns. In many circumstances, the synthetic fibers are white or natural in color; therefore, manufacturing techniques are required to add color to synthetic fibers.
As known to those familiar with the textile arts, various techniques are used to obtain the desired color in various textile products. Typically, conventional techniques include adding liquid colorant to the basic structures of textile products. These basic structures include fibers, yams made from fibers, and fabrics made from yarns. The various techniques for coloring include dying individual fibers before they are formed into yams, dying yarns before they are formed into fabrics, and dying woven or knitted fabrics.
Although the term "dye" is often used in a generic sense, those familiar with textile processes will recognize that the term "dye" most properly describes a colorant that is soluble in the material being colored. In comparison, the term "pigment" should be used to describe insoluble colorants.
Many conventional techniques for coloring synthetic filaments include the incorporation of dye into the polymer material after the filament has been extruded.
Another conventional method in the textiles industry for coloring synthetic filaments includes the "master batch" approach in which colorant is dispersed at a relatively highly concentrated level into a small sample of polymer chip. The highly concentrated colored chip polymer is introduced to the melt spinning system, blended with a larger volume of colorless virgin polymer chip and then extruded to hopefully achieve filaments with the desired color throughout the melt-spinning process. The processes associated with the master batch approach, however, can be expensive and time consuming. For example, the amount of solid dyestuffs introduced into the master batch must be precisely monitored in order to maintain a consistent color. Furthermore, it is extremely difficult to obtain a precise shade or variant of a particular color. Oftentimes it is necessary to re-extrude the polymer to obtain a required color specification of the master batch chip.
Because the masterbatch process typically uses solid dyestuffs, it raises difficulties in accurately handling the proper amounts of solids. Solids are generally harder to meter in precise amounts than are liquids or gases, harder to mix uniformly with other materials, and harder to handle as supply streams (several of which are typically required).
Furthermore, a typical masterbatch process requires multiple high-temperature process steps (i.e., compounding the dyestuff and polymer; drying the compounded mixture; and recompounding the master batch with the full polymer supply) which, both individually and collectively, can cause varying color results or even degradation of the polymer itself.
Condensation polymers offer additional challenges to the masterbatch system. As is known to those familiar with chemical reactions. a condensation polymer results from a reaction in which two monomers or oligomers react to form a polymer and a water molecule. Because such reactions produce water, they are referred to as "condensation" reactions. Because of chemical equilibrium, however, the water must be continually removed from the polycondensation reaction, otherwise it tends to drive the reaction in the other direction; i.e., depolymerize the polymer. This results in a loss of molecular weight in the polymer which is referred to as hydrolytic degradation. In particular the molecular weight (measured by the intrinsic viscosity or "IV") of polyester can easily be decreased by as much as 0.15 dl/g (0.55-0.75 dl/g is considered a good viscosity for filament). As a greater problem--and one that becomes evident during later processing of filament and yarn--the loss in IV is quite variable depending upon the quality of process control of the masterbatch drying and extrusion systems. In particular, obtaining the required color specification of the masterbatch chip sometimes requires re-extruding the polymer to obtain a desired color correction. Unfortunately, such re-extrusion for color matching purposes tends to increase the loss in molecular weight even further.
Masterbatch "chip" is generally introduced into the spinning process using several options each of which tends to provide an extra source of variation for the resulting molecular weight. Because there are several process steps during which molecular weight can be lost, the effect tends to be cumulative and significant. The overall effect is a significant reduction in the molecular weight of the filament that manifests itself as an orientation variability in the resulting yarn. In turn, the orientation variability produces a resulting variability in the physical properties of the yarn such as elongation, tenacity, and draw force.
Such variability in the physical properties of spun yarn generates several additional problems. For example, partially oriented yarn (POY) which is draw textured must exhibit uniform draw force to assure that its preaggregate tension stays within desired specifications. If the yarn properties are outside of such specifications, various problems such as twist surging occur and prevent processing the yarn at commercial speeds. Furthermore, the drawing performance of spun yarns, whether POY, low orientation yarns (LOY), fully oriented yarns (FOY), or staple, is highly dependent upon consistent elongation because the imposed draw ratio cannot exceed the inherent drawability of the spun yarn (as measured by the elongation). Additionally, consistent physical properties of the final drawn or draw textured filament are desirable for optimum performance of fabrics and other end-use products.
In a practical sense, the variation in physical properties from filament to filament, fiber to fiber, and yarn to yarn forces the various textile manufacturing processes and machinery to be continually readjusted whenever a new colored fiber or yarn is introduced. Thus, the problems inherent in masterbatch coloring tend to raise the cost and lower the productivity of later textile processes that incorporate masterbatch colored fibers and yarns.
Copending and commonly assigned application Ser. No. 08/929,831 discloses a particular technique for delivering liquid colorants into the base chip before the chip is melted and includes the use of an injector structure. The liquid colorant can be injected into an extruder or at a point just prior to a manifold system, dependent upon the placement of the injector. The liquid colorants are slowly fed into the base chip in small amounts because the colorant is highly concentrated. In this fashion, the operator is able to better control the amount of liquid colorant deposited into the base chip and, therefore, obtain the desired color during a first attempt. In certain circumstances, however, the slow-feed technique can result in the organic colorants remaining in the bore of the injector for prolonged periods of time. Consequently, the colorant may "cook" (degrade) or solidify due to the heat transfer from the extruder--which is normally heated in order to melt the polymer--to the injector structure.
The solid degradation product resulting from the prolonged heating of the colorant plugs or clogs the bore of the injector and prevents the delivery of the liquid colorant. Thus, when the injector becomes clogged, the operator must halt the production line, locate the clogged injector, and detach the injector from the machinery. Next, the operator must clear the obstruction (i.e., globule of solid dye) from the bore of the injector with specialized tools and then reattach the cleansed injector onto the machinery before resuming normal operations.
Alternatively, an operator could simply replace the defective or clogged injector with a properly functioning injector and immediately resume operations. The defective injector could then be subsequently cleaned during a routine maintenance interval. Regardless of the alternative chosen by an operator to remedy the clogged bore, the defective injector must be physically removed from the production line. Thus, the use of conventional injectors requires additional downtime to clean clogged injectors. Accordingly, there is a need for an injector structure comprising a self-cleaning means for clearing a clogged bore. Such an injector structure would allow an operator to clear the path of the clogged bore without having to remove the entire structure from the melt-spinning machinery.
As referenced above, conventional techniques of coloring textile filaments include positioning an injector adjacent to the extruder. This placement results in the heating and subsequent solidification of the liquid colorant. Accordingly, there is also a need for a cooling means in an injector to reduce the amount of heat transferred from the extruder to the injector structure.


A method and product for sterilizing and drying waste products such as plant sludge, animal excrement and process wastes wherein the waste material is first settled or dewatered to a moisture content between 4% to 60% and then blended and reacted with alkaline earth metal oxides in the presence of an atmosphere of carbon dioxide, and in the absence of the oxygen. After the sludge is blended with the alkaline earth oxides, the carbon dioxide is removed so that air or oxygen will contact the blended constituents. A violent exothermic reaction takes place between the water in the constituents and the alkaline earth oxides causing a rapid rise in temperature of the constituents and thus sterilizing the constituents to produce a safe and useable end product.

1. Field of the Invention
The present invention relates to an improved method for combining waste materials to produce valuable products for agricultural, horticultural, sylvicultural or public use.
Specifically, the present invention relates to a delayed exothermic reaction of alkaline materials with waste materials, such as wastewater treatment plant sludge, animal excrement or process wastes, and additionally with carbon dioxide gas or carbon dioxide solids, to thereby convert said waste materials to useful products such as soil conditioners or fertilizer supplements.
More specifically, the present invention relates to reacting alkaline materials, such as calcium oxide, cement kiln dust, lime kiln dust or similar alkaline materials and combinations thereof with wastewater sludge or animal excrement as well as carbon dioxide gas or carbon dioxide solids in a reactor so as to provide a well blended mixture that reacts exothermically after discharge from the reactor, providing temperatures exceeding the boiling point of water, instantly drying said mixture through rapid evaporation of liquids, dramatically changing the appearance of the product so that the products meet or exceed regulatory requirements for beneficial use of waste materials while improving environmental quality and protecting human health.
2. Description of the Prior Art
Those skilled in sludge management practices are aware that methods for alkaline stabilization or decontamination of waste sludge are presently in use.
In his book titled "Treatment and Disposal of Wastewater Sludges", Ann Arbor Science Inc., publishers, 1979 Edition, P. Aarne Vesilind, reviews the practice of mixing lime and sludge in a common concrete mixer to yield a product which is marketable as a soil conditioner. The sludge is dried and disinfected as a result of an exothermic reaction which approaches (but does not exceed) 100.degree. C.
U.S. Pat. No. 4,226,712 dated Oct. 7, 1980 by Kamei discloses a method of treating water containing wastes by first mixing the waste with an alkaline earth metal oxide such as calcium oxide as a preliminary drying step followed by a second step of removing additional water by drying means at temperatures from 800.degree. C. to 1,450.degree. C. During the first step, the organic sludge is "partly gelated". Kamei also teaches that "the mixture thus heated by the exothermic reaction to a temperature from about 80.degree. C. to 90.degree. C." Additionally, Kamei teaches that the high temperatures do not decompose the organic constituents contained in organic waste and remain in the final product. The sterilized products are used as fertilizers.
In U.S. Pat. No. 4,270,279 dated Jun. 2, 1981, Roediger teaches a method for alkaline stabilization of dewatered sludge cake which results in the formation of sterilized pellets. The claim is that an inexpensive method is provided for sterilizing dewatered sludge cake which is discharged from belt presses wherein the sludge cake is broken into ball-like particles having diameters ranging from 1 to 10 millimeters, dusting these particles with quicklime (calcium oxide) and achieving temperatures "of the bulk matter to about 70.degree. C. to 80.degree. C." The quicklime reacts exothermically with the surfaces of said ball-like particles resulting in a product which can be used as an agricultural product. To achieve complete sterilization, the treated waste had to be stored for four hours. The means for mixing and reacting the sludge with quicklime includes a paddle blender or pug mill.
The RDP Company, Plymouth Meeting, Pa. advertises a so-called "Envessel Pasteurization" process. The process description is that of a screw conveyor or pug mill type mixer that enables reacting dewatered sludge cake and quicklime exothermically, discharging into a jacketed holding hopper, with "supplemental heat added to the vessel to insure the mixture maintains a temperature of 158.degree. F./70.degree. C. for a period of 30 minutes". This process produces a product meeting regulatory agency requirements for PFRP, Process to Further Reduce Pathogens.
U.S. Pat. No. 4,554,002 dated Nov. 19, 1985, granted to Nicholson, discloses a method for beneficiating "low percentage solids" waste water treatment sludge, without prior dewatering, by mixing kiln dust containing a percentage of calcium oxide to form a solidified, disintegratable, friable product which can be eventually granulated after curing and aging for a sufficient period of time. A product is produced which can be applied to land as well as used as a soil conditioner and fertilizer supplement.
Nicholson also disclosed improved methods for treating wastewater sludge in U.S. Pat. Nos. 4,781,842 and 4,902,431. The method "decontaminates" wastewater sludge to a level that meets or exceeds U.S. EPA Process to Further Reduce Pathogens standards. The method mixes sludge with alkaline materials sufficient to raise the pH of the mixture to 12 and above for at least one day, and then the mixture is dried to produce a granular material. So-called "decontamination" is the process of exothermically reacting alkaline materials with sludge to raise the temperature to about 50.degree. C., but not to temperatures sufficient to cause sterilization, thereby reducing and/or eliminating pathogenic microorganisms, but maintaining beneficial non-pathogenic microorganisms, and coupling this step with drying, such as windrowing, to produce a PFRP product.
In U.S. Pat. No. 4,306,978 dated Dec. 22, 1981, entitled "Method for Lime Stabilization of Wastewater Treatment Plant Sludges", granted to the applicant, the subject matter of which is incorporated herein by reference thereto, a method for lime stabilization of wastewater treatment plant sludge is disclosed. The method includes the steps of dewatering sludge and rapidly and intimately mixing and reacting sludge cake with quicklime (calcium oxide) so as to produce stabilized sludge pellets.
In U.S. patent application Ser. No. 546,426 for "Improved High Rate Method for Alkaline Stabilization, Beneficiating and Pelletizing of Wastewater Treatment Plant Sludges now U.S. Pat. No. 4,997,572," also by the applicant, an improved method is disclosed which exothermically reacts alkaline materials with waste material, beneficiates said materials, and forms pellets having a skin of calcium carbonate. The carbonates are formed as the last step of the process by reaction of calcium hydroxide, contained in the pellet, with carbon dioxide gas or carbon dioxide solids (dry ice).
The aforesaid patented methods of the applicant are advantageously and efficiently accomplished in a blender-dryer-reactor invented by the applicant and described in U.S. Pat. No. 3,941,357. The method of U.S. Pat. No. 4,306,978 and the applicants patented apparatus have been widely accepted by the pollution control industry with many successful installations in the United States.
Many of the aforesaid methods of alkaline stabilization or decontamination are presently in practice today, but all have limitations when compared to the new method of the applicant. Because of the increasing demand for viable alternative for disposing of waste materials and the promotion of practices that provide for beneficial use of sludge, the new inventive method addresses the limitations of present methods and provides a beneficial product from waste materials that not only will have appeal for public use by virtue of its physical appearance, but more importantly, because of the high rate, subsequent instant drying with high efficiency, can be shipped long distances without fear of degradation so that said products can be economically used as fertilizer supplements in third world countries.
When compared to the instant invention, none of the aforesaid methods teach the method of obtaining of temperatures in excess of 100.degree. C., such as temperatures up to or exceeding 117.degree. C., which result from the exothermic reactions. Neither do any of the methods delay or retard the exothermic reaction so that the chemical reactions can take place with high efficiency after a highly accurate blending of the components of the mixtures is assured. Those skilled in the art of mixing, blending and reacting materials recognize that materials cannot be commingled or dispersed accurately as said materials are changing stage or state. Another limitation of present inventions is the relatively long drying periods when dried by natural means such as air drying, or the additional equipment and fuel required for drying in a drying apparatus. This compares to the subsequent relatively instant drying as the exothermic reaction takes place at high temperatures exceeding 100.degree. C. for the new method.
Extended drying periods also require costly land storage area as well as additional labor and material handling to transport material to and from said storage area.
Most of the products provided by the methods presently in use have moisture content ranging from 10% to 35%. The products having the least amount of moisture require drying periods of at least 30 days. This is another limitation of the present methods in that the new process can selectively provide a moisture content in the product, ranging from 50% to less than 10%, by varying the ratios of components of the mixture and reaction. Additionally, the new product is so well blended, reacted and dried, that there remains no pockets of unblended material and therefore no pockets containing a higher moisture content which could cause spoilage or degradation over periods of time. The uniform drying of the new inventive product enables its packaging and shipping over long distances without degradation.
The color of products produced by presently existing methods range from black to light gray, whereas the new product has an off-white appearance. This off-white appearance is more acceptable to the public since it does not resemble a product made from waste sludge.
It is accordingly an object of the present invention to provide a novel, improved method for reacting alkaline materials, carbon dioxide and waste materials, such as wastewater sludge, animal excrement or process wastes in a conventional blender-reactor, preferably a plow blender type so as to provide a delayed exothermic reaction after discharge from the blender-reactor, the reaction resulting in the beneficial use of waste materials while improving environmental quality and protecting human health.
It is a further objection of the invention to provide a method of treating sludge wherein temperatures exceeding the boiling point of water are obtained with subsequent relatively instant drying through rapid evaporation of liquids from waste materials while dramatically altering the appearance of the waste products.
It is also an object of the present invention to provide sterile products by thermal destruction of microorganisms, high dry solids content of the product, or a combination of thermal destruction and high dry solids content which is not life supporting.
Accordingly, the invention provides for the reduction in pathogens that is equivalent to and exceeds the reduction of other approved USEPA standards for PFRP, the Process to Further Reduce Pathogens, as per USEPA Appendix II of 40 CFR 257, which standards state in part as follows:
Heat drying: Dewatered sludge cake is dried by direct or indirect contact with hot gases, and moisture content is reduced to 10% or lower. Sludge particles reach temperatures well in excess of 80.degree. C.
Other methods: Other methods of operating conditions may be acceptable if pathogen and vector attraction of the waste (volatile solids) are reduced to an extent equivalent to the reduction achieved by any of the above (other) methods.
In a 1985 memorandum regarding 40 CFR 257 regulations, the USEPA outlined another qualifying PFRP process, namely, the reduction of pathogenic bacteria, animal viruses, and parasites below detectable limits of one plaque forming unit (PFU) per 100 ml of sludge for animal viruses; three colony forming units (CFU) per 100 ml of sludge for pathogenic bacteria; and one viable egg per 100 ml of sludge for parasites. Additionally, vectors such as flies or rats should not be attracted to the product. Since Nicholson per U.S. Pat. Nos. 4,781,842 and 4,902,431 meets the aforementioned standard by providing temperatures of 50.degree. C. and dryness of 65%, the new inventive process exceeds the temperatures of 50.degree. C. with temperatures exceeding 100.degree. C., and with a dryness exceeding 90%.
The present invention also beneficiates waste materials by synergistically combining waste materials such as waste sludge and kiln dusts to thereby effect soil conditioners and fertilizer supplements, the products containing nitrogen, phosphorus, potassium, trace nutrients and organic matter, as well as calcium from calcium carbonate, that can be land applied. The calcium carbonate of the product is known to degrade more slowly than hydrated lime and therefore provides beneficial slow release of alkalinity to cropland. The invention also eliminates the necessity for product storage or extra material handling. It provides a free flowing product that can be marketed as a free flowing powder or as granules, micro-pellets or pellets; have a innoxious odor; reduce vector attraction; reduce bulk density and color so that the products do not appear "sludge-like" to the general public.
The invention also converts and beneficiates waste materials into valuable products for utilization as soil conditioners or fertilizer supplements in agricultural applications for food and feed crops; for horticultural applications such as plants and use in nurseries; for sylviculture to increase forest productivity and revegetate forest lands devastated by fire, land slides, volcanos or other natural disasters; public use such as turf maintenance or production, strip mine reclamation, covering expired landfills; fertilizing highway median strips; or additionally addressing process waste for preparing process waste for approved landfill applications.

Delayed, exothermic, alkaline sterilization method for treating wastewater sludges


A document indexing and retrieval system and method which assigns weights to the key words and assigns a relative value to pairs of key words (i.e. defines a relative relation on K.times.K) based on their frequency of occurrence and co-occurrence in the document data base. In response to a query both the weights and this relative relation are used to suggest additional and/or alternative key words which are very likely to find relevant documents. Documents are then ranked by number of hits adjusted for the weights of hit words and their relative values.

1. Field of the Invention
This invention relates generally to document storage and retrieval systems and more particularly to a method of indexing documents so that they can be retrieved in response to a query in order of their relevance to the query. It also permits, general query to be easily modified based on the content of the documents so that the new query will retrieve documents that are relevant to the original query.
2. Description of the Prior Art
Document retrieval based on indexing of the documents in a document data base is well known. Typically the documents are indexed by creating an index file which records the documents that each word is in. Then when the user inputs a query, the documents that contain one or more words of the query can be quickly identified. However, if the query consists of general words that are not terms of art, the query may produce unsatisfactory retrieval results by either producing few documents that are of interest to the user or producing many documents that are not interesting to the user or both.

Method of indexing and retrieval of electronically-stored documents


An add-on brake system includes a housing accommodating a linear actuator including: an electric motor having a rotor and a stator; a nut arrangement coupled to the rotor; a linear threaded plunger associated having a first end linearly protruding from one end of the arrangement and a second end linearly protruding from an opposite end thereof; an inboard brake pad coupled to the housing; and an outboard brake pad associated with the second end, oriented transverse to the plunger. The plunger has an initial unclamped position in which the second end protrudes to an extent n1 from the other end of the arrangement, yielding a spacing S1 between the inboard and outboard brake pads, and a final clamped position in which the second end protrudes to an extent n2>n1 from the other end of the arrangement, yielding a spacing S2<S1 between the pads.

It is well known in the field of aviation to provide air vehicles, including aircraft and other airborne vehicles, with a brake system, configured for stopping the air vehicle during its taxiing when on the ground.
Calipers are a common brake arrangement, used also in air vehicle, in which two brake pads are configured for clamping therebetween a portion of the wheel (or an element fixedly associated therewith), thereby preventing it from rotating, effectively stopping the air vehicle.
Hydraulic systems can also be substituted by electromechanical systems which can weigh less and require less maintenance. One example of such a mechanical system is a geared caliper system in which an arrangement of gears associated with an electric motor replacing the hydraulic actuation.
Such electromechanical brake systems can incorporate a powerful motor allowing the brake system to be incorporated in large-scale aircrafts. An example of this is disclosed in US2014/0000993 which relates to an electromechanical brake system includes a base carrier provided with a pair of pad plates for application of pressure to a disc, a caliper housing supported by the base carrier to be movable forward and backward to apply pressure to the pad plates, a pressing member including a ball nut installed at the caliper housing to convert rotational motion into rectilinear motion to apply pressure to the pad plates and a ball screw coupled to the ball nut, a force sensor installed at the ball nut to sense load produced by the ball nut, a motor to produce rotational force to operate the pressing member, and a speed reducer connected to a rotating shaft of the motor to transfer driving force to the pressing member, wherein the speed reducer may be adapted to change a reduction ratio depending on presence of load sensed by the force sensor.
In general, the replacement of hydraulic systems with mechanical/electric systems is performed in other avionic systems other than the brakes. One such example is provided in the research paper "Analysis of Electro-Mechanical Actuator Systems in More Electric Aircraft Applications" by Mohsen Torabzadeh-Tari, KTH Electrical Engineering, ISBN 91-7178-0998.
Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.


A track apparatus for egg breaking mechanisms is provided which comprises a pair of endless chains extending along an endless moving path and carrying the egg breaking mechanisms, a pair of drive sprockets held in driving engagement with the chains, a pair of idle sprockets held in engagement with the chains, and a chain tensioning mechanism for slidably guiding the chains.

1. Field of the Invention:
This invention relates to a track apparatus for egg breaking mechanisms which can be advantageously incorporated in an automatic egg breaking apparatus for successively breaking eggs and taking out their contents.
2. Description of the Prior Art:
As is well known, eggs have found wide use. For example, the egg yolk may be used as a material for making mayonnaise or other food products. The egg white (albumen) may be used for making pharmaceutical products or as a binder for protein products. Due to such wide use of the egg, it is absolutely necessary in industry to use an automatic egg breaking apparatus for breaking eggs and taking out their contents at high speed.
Japanese Patent Publication No. 61-59089 discloses an egg breaking apparatus wherein an endless chain conveyor has a track apparatus that carries a plurality of egg breaking mechanisms at a constant pitch along the endless moving path of the chain conveyor. The chain conveyor is held in engagement with a plurality of sprocket assemblies as direction change assemblies, so that the moving path of the chain conveyor is divided by the direction change assemblies into different regions where each of the egg breaking mechanisms is caused to perform different operations which include egg reception, egg breaking, cleaning, and etc. One of the sprocket assemblies is a drive sprocket assembly for causing movement of the chain conveyor.
According to the prior art arrangement, all of the direction change assemblies are in the form of sprocket assemblies which cannot be conveniently cleaned due to the presence of the sprocket teeth. Thus, the prior art track assembly as a whole suffers a hygienic problem resulting from bacterial breeding at the sprocket assemblies which are fouled by the egg residues but insufficiently cleaned later.

Track apparatus for egg breaking mechanisms


An interferometric apparatus for monitoring changes of the refractive index of An interferometri1capillary tubes comprising a source of coherent light, which is arranged with respect to a capillary tube which is part of a capillary liquid chromatographic system or a capillary electrophoretic system, such that the coherent light beam strikes the capillary tube about perpendicular to its longitudinal extension. In the forward direction of the coherent light beam, behind the capillary tube, the apparatus comprises a photoelectric detector for monitoring a resulting interference fringe pattern and the shifts thereof, which is connected to an evaluation electronics. Between the light source and the capillary tube there is arranged a beam splitting optical element for generating a converging probe beam, which travels along a probe beam axis and strikes the capillary tube at its bore, and a converging reference beam, which travels along a reference beam axis, that extends generally parallel to the probe beam axis and is located in close vicinity to the probe beam axis, and which does not strike the capillary bore.

The invention relates to an interferometric apparatus for monitoring changes of the refractive index of fluid samples in capillary tubes, in particular to a refractive index based measurement system used for example in capillary liquid chromatography or capillary electrophoresis.
In modern analysis of chemical samples there exists a great demand for techniques involving only a small volume of the test sample. Capillary liquid chromatography and capillary electrophoresis belong to the most exciting and potentially useful microvolume separation techniques. Among the most important features of these new instrumental techniques are high peak resolution, short analysis time, and the minimal amounts of test sample required. The total column volume in these new techniques amount to as little as only a few microliters, and the required sample volumes are in the nanoliter or even in the picoliter range. Various instrumental aspects of these capillary-based, fluid-phase separation schemes contribute to the overall system performance. A major instrumental limitation of the performance of these techniques is the lack of highly sensitive microvolume detectors and the fact, that the so-called "off-column" detection, where the separated bands of the test sample are transferred to the detection cell, is associated with unwanted re-mixing effects.
As a solution to the problems associated with the "off-column" detection these capillary-based techniques employ so-called "on-column" detection methods, which do not distort the spatial profile of the eluting peaks. Among these "on-column" detection methods the monitoring of changes of the refractive index of the fluid test sample proves to be most promising. This technique is based on tile detection of tile phase shift of a coherent light beam passing through the fluid test sample, which occurs due to refractive index changes of the test sample with respect to the carrier buffer or the solvent contained within the capillary tube. The method makes use of the fact, that the phase shifts of the light beam transversing the fluid test sample flowing through the capillary tube are linearly related to the changes of the refractive index of the test sample.
For monitoring the changes of the refractive index of the test sample in capillary tubes a refractive index measurement system has been developed. The refractive index measuring system consists basically of an interferometer, having a source of coherent light, which is directed at the capillary tube, a photoelectric detector, and an evaluation electronics. The light beam, usually coming from a laser source, strikes the capillary tube; part of the light beam transverses the flowing path of the test sample and interacts with the test sample; whereas part of the light beam is reflected at the glass walls of the capillary. Thus, the light beam is split at the capillary tube, more specifically at its inner optical interface, into a probe beam and into a reference beam having a phase difference, which upon recombination of the two beams results in a generally asymmetric interference fringe pattern in the far field. The interference fringe pattern is measured by the photoelectric detector in the forward direction of the probe beam, and shifts laterally as the refractive index of the test sample flowing through the capillary tube changes.
Refractive index measuring systems of the kind described before are known from the prior art. The performance of these measuring systems was distinctly increased by arranging the capillary tube within material, which matches or almost matches the refractive index of the material the capillary tube is made from, as described in an article by A. E. Bruno, B. Krattiger, F. Maystre and H. M. Widmer, Anal.Chem., 1991, 63, page 2689-2697. In doing so, the boundary optical interfaces, which the laser beam encounters upon its propagation along the light path and striking the capillary tube, are reduced, the interference fringe pattern becomes more simple and easier to evaluate, and the signal/noise ratio is enhanced. In spite of the good results, which are achieved with the thus improved refractive index measuring systems known from the prior art, these devices still can be further improved. In case the capillary tube is not surrounded by a matching material, the resulting interference fringe pattern is rather complex and cannot be reliably evaluated and interpreted. Also, irregularities on the boundary surfaces of the capillary tube may modify the reference beam in an unexpected way.

Interferometric apparatus for monitoring changes of the refractive index of fluid samples in capillary tubes