The invention relates to the use of precrosslinked silicone elastomer particles with an organopolymer shell as the formulation constituent in powder coating material compositions based on thermoplastic or thermosetting binding agents, the silicone elastomer particles containing (a) 5 to 95% by weight, in relation the total weight of the copolymerisate, of a nucleus polymer of the general formula (R.sub.w SiO.sub.2/2).sub.x.(RSiO.sub.3/2).sub.y.(SiO.sub.4/2).sub.z with x=5 to 99.5 mol %, y=0.5 to 95 mol %, z=0 to 30 mol %, and (b) 5 to 95% by weight, in relation to the total weight of the copolymer, of a shell made of an organopolymer of ethylenically mono or multi-unsaturated monomers, R standing for identical or different monovalent C.sub.1 -C.sub.6 alkyl or alkenyl residues or substituted hydrocarbon residues.

Powder coatings consist of solid binders based on thermoplastic or thermosetting polymers, such as epoxy, polyurethane, acrylic or polyester resins, on pigments and on further additives, for example crosslinking catalysts. These compositions are applied in powder form to predominantly metallic substrates. The thermoplastic or thermosetting binders mentioned are generally hard but brittle; to improve the film properties, therefore, impact modification of the polymer systems is frequently necessary.
In order to obtain good impact strengths while retaining the existing, desired polymer properties such as hardness, dimensional stability and mechanical strength, the impact modifier must be incorporated into the thermoplastic or thermosetting systems in the form of separate, discrete microphases with optimized particle size and particle morphology. This can be carried out in a controlled and reproducible manner only by employing the impact modifier in the form of particles with a defined size and a defined size distribution as blend component. In addition, the particulate modifier must be highly compatible with the polymer matrix. In that case, the domain sizes of the modifier phase are defined exactly by way of the particle diameter. Only in the case of complete phase separation does no undesirable plastification of the polymer matrix occur, which would result in a loss of or adverse effect on the properties of the polymer matrix such as hardness, dimensional stability and mechanical strength.
Silicones are known as modifiers for thermoplastics or thermosets and are of particular interest since they not only increase the impact strength but also improve low-temperature flexibility, weathering resistance, resistance to temperature change and chemical resistance of thermoplastic and thermosetting organic-polymer systems. Generally disadvantageous, however, is the fundamental incompatibilty of silicones with organic polymers. Because of this incompatibility, the use of silicone oils and silicone resins as additives to binders for powder coatings generally gives rise to problems with processing, such as contamination in the mixing and extrusion equipment. On application it is possible for defects in flow to occur, and migration of the silicones produces problems with adhesion and in the context of overcoatability.
In U.S. Pat. No. 5,280,098, epoxy-functional silicone resins are described as sole binder or as binder constituent, in combination with organic resins, for the formulation of powder coatings. The introduction of the epoxide groups is intended to improve the elasticity and the compatibility with the organic resin. The concept of controlled microphase separation cannot be realized with the epoxy-functional silicone resins, since they do not have a particulate structure with a defined particle diameter.
U.S. Pat. No. 5,227,435 proposes the substitution in powder coatings of the polyester binder by silicone-modified polyesters which are obtained by condensing OH-functional siloxanes with glycol, followed by esterification with carboxylic acids and reaction with anhydrides. EP-A 275051 relates inter alia to acrylate-grafted silicone resins which are described as binders for powder coatings having an improved profile of properties of the coating films obtainable therewith.
A disadvantage of the procedure according to U.S. Pat. No. 5,227,435 and EP-A 275051 is that the silicone copolymers described therein are described as binders for replacing the conventional thermoplastics or thermosets. Consequently, the silicone constituent must be incorporated into the respective polymer system by complex chemical reaction, each specific binder system having to be newly synthesized from scratch. In addition, the contamination problems typical of silicones are not ruled out by such binder systems. Here too, there is no controlled microphase separation, since the modifiers concerned again do not have a particulate structure.
EP-A 217257 relates to noncrosslinked or crosslinked diorganosiloxane polymers grafted with organic polymer. These powders are processed per se and are not employed as additives. The processing, carried out by means of rolling, calendering and kneading, produces elastomeric rubber masses but not pulverulent coating compositions based on thermoplastic or thermoset powders.
The object was therefore to provide powder coating compositions which are based on conventional thermoplastic or thermosetting binders and which have improved impact strength and weathering resistance while at the same time retaining the existing, desired polymer properties of the binder such as hardness, dimensional stability and mechanical strength.
It has surprisingly been possible to achieve this object by the use of precrosslinked silicone elastomer particles with an organic-polymer shell as a formulation constituent in powder coatings based on thermoplastic or thermosetting binders.
One subject of the invention is the use of precrosslinked silicone elastomer particles with an organic-polymer shell as a formulation constituent in powder coating compositions based on thermoplastic or thermosetting binders, the silicone elastomer particles comprising
a) from 5 to 95% by weight, based on the total weight of the copolymer, of a core polymer of the general formula (R.sub.2 SiO.sub.2/2).sub.x.(RSiO.sub.3/2).sub.y.(SiO.sub.4/2).sub.z where x=5 to 99.5mol %, y=0.5 to 95 mol %, z=0 to 30 mol %, and PA1 b) from 5 to 95% by weight, based on the total weight of the copolymer, of an organic-polymer shell of mono- or polyethylenically unsaturated monomers, PA1 a) from 5 to 95% by weight, based on the total weight of the copolymer, of a core polymer of the general formula (R.sub.2 SiO.sub.2/2).sub.x.(RSiO.sub.3/2).sub.y.(SiO.sub.4/2).sub.z where x=5 to 99.5 mol %, y=0.5 to 95 mol %, z=0 to 30 mol %, and PA1 b) from 5 to 95% by weight, based on the total weight of the copolymer, of an organic-polymer shell of mono- or polyethylenically unsaturated monomers, PA1 a) from 20 to 80% by weight, based on the copolymer total weight, of a core polymer (R.sub.2 SiO.sub.2/2).sub.x.(RSiO.sub.3/2).sub.y.(SiO.sub.4/2).sub.z where x=50 to 99 mol %, y=1 to 50 mol %, z=0 to 20 mol %, and PA1 b) from 20 to 80% by weight, based on the copolymer total weight, of an organic-polymer shell of mono- or polyethylenically unsaturated monomers,
and R denoting identical or different monovalent alkyl or alkenyl radicals having 1 to 6 carbon atoms, aryl radicals or substituted hydrocarbon radicals.
Another subject of the invention are powder coating compositions based on thermoplastic or thermosetting binders which comprise as formulation constituent precrosslinked silicone elastomer particles with an organic-polymer shell, the silicone elastomer particles comprising
and R denoting identical or different monovalent alkyl or alkenyl radicals having 1 to 6 carbon atoms, aryl radicals or substituted hydrocarbon radicals.
The silicone elastomer particles with an organic-polymer shell which were employed as a formulation constituent, and processes for their preparation, are described in EP-A 492376 (U.S. Pat. No. 5,223,586). Precrosslinked silicone elastomer particles means that these particles are crosslinked by way of units (RSiO.sub.3/2) and (SiO.sub.4/2). The silicone elastomer particles with an organic-polymer shell preferably comprise
and R being as defined above.
The finely divided graft copolymers preferably have a mean particle diameter of from 10 to 300 nm, particularly preferably from 30 to 150 nm. The particle sizes may fluctuate within the abovementioned range; preferably, a monomodal particle-size distribution is present with a maximum polydispersity index of .sigma..sub.2 =0.2.
The radicals R are preferably alkyl radicals, such as the methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, amyl, hexyl radical; alkenyl radicals, such as the vinyl, allyl, butenyl and 1-hexenyl radical; aryl radicals, such as the phenyl radical; or substituted hydrocarbon radicals, such as halogenated hydrocarbon radicals, mercaptoalkyl radicals, cyanoalkyl radicals, aminoalkyl radicals, acyloxyalkyl radicals, hydroxyalkyl radicals.
Particularly preferred radicals are methyl, ethyl, propyl, phenyl, vinyl, allyl, 1-hexenyl, 3-meth-acryloxypropyl and 3-mercaptopropyl, less than 30 mol % of the radicals in the siloxane polymer being vinyl, 3-methacryloxypropyl or 3-mercaptopropyl groups.
Monomers employed for the organic polymer compoment b) are preferably acrylates or methacrylates and mono- or diesters of fumaric and maleic acid with aliphatic alcohols and diols having 1 to 10 carbon atoms, acrylamides and methacrylamides, acrylonitrile, styrene, p-methylstyrene, .alpha.-methylstyrene, divinylbenzene, vinyl acetate, vinyl propionate, maleimide, vinyl chloride, mono- and divinyl ethers, ethylene, butadiene, isoprene and chloroprene. Particular preference is given to styrene and to acrylates and methyacrylates of aliphatic alcohols having 1 to 4 carbon atoms, for example methyl (meth)acrylate, butyl (meth)acrylate and glycidyl-(meth)acrylate. Both homopolymers and copolymers of the abovementioned monomers are suitable as organic polymer component.
The polysiloxane graft base is prepared according to the emulsion polymerization process by metering in the corresponding mixture of monomeric silanes of the type R.sub.a Si(OR').sub.4-a, where a=0, 1 or 2, or, if desired, low molecular mass siloxanes of the general formula (R.sub.2 SiO).sub.n where n=3 to 8, to an agitated emulsifier/water mixture. The radical R has the definitions already given. R' represents alkyl radicals having 1 to 6 carbon atoms, aryl radicals or substituted hydrocarbon radicals, with methyl, ethyl and propyl radicals being preferred. The silane or the silane mixture or silane/siloxane mixture is added in metered form. The emulsion polymerization is carried out at a temperature of from 30 to 90.degree. C., preferably from 60 to 85.degree. C., and preferably at atmospheric pressure. The pH of the polymerization mixture is from 1 to 4, preferably from 2 to 31.
Examples of suitable silanes are, for silanes of the general formula R.sub.2 Si(OR').sub.2, dimethyldiethoxysilane or dimethyldimethoxysilane; for oligomers of the formula (R.sub.2 SiO).sub.n where n=3 to 8, octamethylcyclotetrasiloxane or hexamethylcyclotrisiloxane; for silanes of the general formula RSi(OR').sub.3, methyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane or methacryloxypropyl-trimethoxysilane, and, for silanes of the general formula Si(OR').sub.4, tetramethoxysilane or tetraethoxysilane.
In the last step of the preparation process the abovementioned ethylenically unsaturated monomers are grafted onto the polysiloxane graft base. Grafting takes place according to the emulsion polymerization process in the presence of water-soluble or monomer-soluble free-radical initiators. The graft copolymers can be isolated from the emulsion by known methods. For example, by coagulating the latices by means of salt addition or addition of polar solvents or by spray drying.
The degree of crosslinking of the silicone core determines its elastic properties and can be established specifically in a manner familiar to the person skilled in the art by an appropriate choice of the starting components, corresponding alkoxysilanes and/or siloxanes in order to obtain units (RSiO.sub.3/2) and/or (SiO.sub.4/2). The incorporation of silane units comprising olefinically unsaturated double bonds, for example vinyl radicals or 3-methacryloxypropyl radicals, permits, in the subsequent graft polymerization, a chemical bonding of the organic-polymer shell to the silicone core by covalent bonds. By choosing suitable monomers for the synthesis of the organic polymer shell b) it is possible to tailor the organic-polymer shells. Thus by grafting a copolymer shell comprising, for example, methyl methacrylate (high Tg) and n-butyl acrylate (low Tg) onto a crosslinked silicone core it is possible to establish specifically the softening temperature of the polymer shell and thereby to match it exactly to the requirements during processing, especially extrusion, of the powder coating components. By grafting a copolymer shell comprising, for example, methyl methacrylate and glycidyl methacrylate onto a crosslinked silicone core, on the one hand it is possible, owing to the epoxide functions in the organic-polymer shell which are introduced with glycidyl methacrylate, to obtain a matrix attachment between modifier particles and binder resin of the powder coating composition, and on the other hand these modifier particles are able to act as crosslinking agents in binders based on polyester resins.
The most preference, accordingly, is for cross-linked silicone elastomer particles with a core comprising (R.sub.2 SiO.sub.2/2).sub.x.(RSiO.sub.3/2).sub.y where x=80-99 mol % and y=1-20 mol %, R being able to be identical or different and having the definition R=methyl, 3-methacryloxy-propyl, and with a shell of poly(methyl methacrylate) or copolymer shells of methyl methacrylate and butyl acrylate or glycidyl methacrylate.
The proportion of the core polymer, based on the total copolymer weight, is particularly preferably 50-75% by weight, and accordingly the proportion of the organic-polymer shell is particularly preferably 25-50% by weight. This corresponds to an organic-polymer degree of grafting of 33-100%.
The additive nature of the silicone elastomer particles with an organic-polymer shell and the ease of incorporation by compounding permit use with all common binder systems for powder coatings. Examples of binder systems for powder coatings are epoxy resins, epoxy-novolak resins, polyester resins, epoxy-polyester resins, polyester hybrid resins, polyacrylate resins, polymethacrylate resins, polyurethane resins, polyethylene resins (HD-PE, LD-PE, LLD-PE), polypropylene resins, polyvinyl chloride resins, ethylene/vinyl acetate copolymers, polyamides and cellulose esters.
The silicone elastomer particles with an organic-polymer shell are generally added in a quantity of from 0.5 to 20% by weight, preferably from 1.0 to 10% by weight, based in each case on the total weight of the silicone elastomer component and binder component. The silicone elastomer particles with an organic-polymer shell can be processed to powder coatings after premixing with binder, pigments and further additives, for example hardener, by extrusion or comparable mixing processes in a temperature range from 5 to 160.degree. C., preferably from 60 to 110.degree. C. This corresponds to the customary procedures for preparing powder coatings. Comminution, grinding and sieving can be carried out in accordance with the state of the art.
In general, the procedure is such that the binder component is precomminuted and is mixed intensively with the silicone elastomer particles, with pigments, catalysts and additives, for example in fluid mixers. The composition passes via a metering device into an extruder, in which the material is melted and homogenized at temperatures which lie above the softening point of the binder and below the activation temperature of the crosslinking catalyst (hardener). The extruded, pastelike material emerges from the extruder die and is then rolled out by rollers to a layer thickness of from 2 to 3 mm, cooled, comminuted and finely ground; finally, the powder is sieved to the desired particle size.
The powder coating compositions obtainable in this way can be processed using the application methods which are known for powder coatings, for example by the electrostatic spraying, electrostatic coating, triboelectric and corona processes, fluidized-bed sintering, electrostatic fluidized-bed sintering, bulk sintering and centrifugal casting. A common feature of all sintering methods is that the material is melted under the influence of heat during film formation; in the case of thermosetting plastics, this is then additionally followed by a curing cycle. A common feature of the electrostatic application methods is that the powder is generally applied to a cold, earthed base material. Owing to their electrostatic charge the powder particles adhere to the workpiece, which is then heated in an oven, whereby the particles melt and--in the case of curable polymers--are cured.
The powder coating composition according to the invention is suitable for all powder coating applications, for example metallic finishing in the automotive sector (clearcoat, topcoat, interior finish, filler, stone-chip protection and underbody protection), of rail-bound vehicles and aircraft (exterior finish), domestic appliances (for example chest freezers, refrigerators, dishwashers), architectural components both external (window frames, exterior panels, doors, gates) and internal (metal furniture, lamp housings), bicycles, snowmobiles, shipping containers, signs, aluminium wheel rims.
In the powder coating compositions according to the invention, the required criterion of microphase separation for improving the impact strength in thermoplastics and thermosets while at the same time retaining the existing polymer properties such as hardness, dimensional stability and mechanical strength is met. In addition to an improvement in the (low-temperature) impact strength, the powder coating compositions also achieve, for example, improved gloss retention (weathering resistance) and scratch resistance, with no adverse effect on hardness, dimensional stability and mechanical strength. The silicone elastomer particles with an organic-polymer shell can be incorporated (compounded) as formulation constituents into powder coating compositions simply and without problems in accordance with conventional process techniques. Contamination problems and flow defects do not occur. Overcoatability of the resulting powder coatings is provided.

Precross-linked silicone elastomer particles with organopolymer shell as formulation constituent in powder coating materials


Some embodiments of the present invention provide programming operations for reducing a program time for a nonvolatile memory device. A nonvolatile semiconductor memory device is programmed by receiving data to be programmed into memory cells from a host, programming the data into the memory cells, performing a verify read operation to determine whether the data has been successfully programmed into the memory cells, and performing a Y-scan operation while performing the verify read operation to sequentially scan and output data read from bit lines coupled to the memory cells.

1. Field of the Invention
The present invention relates to nonvolatile memory devices and, more particularly, to flash memory devices,
2. Description of the Related Art
Electrically erasable and programmable flash memory can preserve data even when electric power is not provided. In particular, because such flash memory has a string structure in which a plurality of flash memory cells are connected in series, NAND-type flash memory may facilitate integration and can be provided at low cost. For these reasons, NAND-type flash memory has been used as data memory in diverse portable products.
A flash electrically erasable programmable read-only memory (EEPROM) cell transistor may be programmed or erased using the Fowler-Nordheim (FN) tunneling mechanism. An operation of erasing the cell transistor may be performed by applying a ground voltage of 0 V to a control gate of the cell transistor and applying a voltage (e.g., 20 V) higher than a power supply voltage to a semiconductor substrate (or bulk). According to such a bias condition, a strong electric field may be formed between a floating gate and a bulk due to a great voltage difference therebetween. As a result, electrons in the floating gate are discharged to the bulk due to an FN tunneling effect. Here, the threshold voltage of the erased cell transistor may shift to a negative value, for example, −3 V. This state is defined as data "1" and an EEPROM cell in this state is referred to as an "ON-cell."
An operation of programming the cell transistor is performed by applying a voltage (e.g., 18 V) higher than the power supply voltage to the control gate and applying the ground voltage to a drain and the bulk. Under such a bias condition, electrons are injected into the floating gate of the cell transistor due to the FN tunneling effect. Here, the threshold voltage of the programmed cell transistor may shift to a positive value, for example, +1 V. This state is defined as data "0" and an EEPROM cell in this state is referred to as an "OFF-cell."
FIG. 1 is a block diagram of a conventional NAND-type flash memory device. Referring to FIG. 1, the NAND-type flash memory device includes a memory cell array 10, a row selection circuit (or a row decoder circuit) 12, a page buffer circuit (or a data sensing and latching circuit) 14, and a column decoder circuit 16.
The memory cell array 10 includes a plurality of memory blocks BLK0 through BLKn (where "n" is a positive integer), each of which includes a plurality of strings. As illustrated in FIG. 1, each string includes a string selection transistor (SST) connected to a corresponding bit line, e.g., BL0, a ground selection transistor (GST) connected to a common source line (CSL), and memory cells MC15 through MC0 connected between the SST and the GST. The SST, the memory cells MC15 through MC0, and the GST are respectively connected to a string selection line (SSL), word lines WL15 through WL0, and a ground selection line (GSL). Block selection transistors BS17 through BS0 respectively corresponding to the lines, i.e., the SSL, the word lines WL15 through WL0, and the GSL are controlled in common by a block selection signal BS.
The row selection circuit 12 selects one word line (or one page) among the word lines WL0 through WL15 through the block selection transistors BS0 through BS17. The page buffer circuit 14 temporarily stores data to be stored in memory cells of the selected page or senses data stored in the memory cells of the selected page. The page buffer circuit 14 comprises a plurality of page buffers (or data sensing and latch blocks) respectively corresponding to columns, i.e., bit lines related with the selected page. Data bits sensed from the memory cells of the selected page are output through the column decoder circuit 16 in predetermined units (for example, in byte units (×8)).
FIG. 2 illustrates part of a conventional column decoder circuit. The column decoder circuit illustrated in FIG. 2 corresponds to a single data line. The same circuit structure as that illustrated in FIG. 2 may be provided to correspond to each of other data lines. In FIG. 2, a reference character "ND_LAT" denotes a latch node of the page buffer circuit 14 shown in FIG. 1. First selection signals YA0 through YA15 are sequentially activated, and simultaneously, second selection signals YB0 through YB15 are sequentially activated. For example, while each of the second selection signals YB0 through YB15 is activated, the first selection signals YA0 through YA15 are sequentially activated. As can be seen from such a structure and control method, for example, a single data bit DL0 is selected from among 256 latched data bits ND_LAT0 through ND_LAT254.
A page size may increase to meet users' demands for increase in data input/output speed. However, when the page size increases, the following problems may occur: As is known, a program/erase operation includes a verify operation for determining whether a memory cell is normally programmed or erased. During the verify operation, the memory cells, i.e., bit lines of the selected page are sequentially scanned. This scan operation is referred to as "verification scan,""column scan," or "Y-scan".
The erase operation generally takes a relatively long time (e.g., 2 ms). Accordingly, the erase operation is not usually restricted by time taken for the Y-scan (hereinafter, referred to as "Y-scan time"). However, because the page program operation generally takes a relatively short time (e,g., 240 μs or less), the Y-scan time may not be ignored in the page program operation. Moreover, because a page program includes an algorithm for preventing a memory cell from being excessively programmed, the Y-scan time is not ignorable.
FIG. 3 illustrates conventional programming operations. In stage 301, a host sends data to a static random access memory (SRAM) to perform a program operation. When a command indicating sequential data input is applied to a flash memory having an array of memory cells to be programmed, the SRAM transmits the data to a page buffer of the flash memory and address data and sequential data are sequentially input to an address buffer circuit ad a page buffer circuit of a memory device in stage 302. Thereafter, when a command indicating start of a programming process is applied to the memory device, a high-voltage generation circuit operates to generate high voltage to be applied to a gate in stage 303. As described above, bit lines are set to a power supply voltage (or a program-inhibit voltage) or a ground voltage (or a program voltage) according to data loaded into the page buffer circuit in stage 304, which is referred to as a bit line setup operation. After the bit lines are set to the power supply voltage or the ground voltage, the high voltage generated by the high-voltage generation circuit is applied to a selected word line and the program operation is executed in stage 305. After a predetermined period of time under the above-described bias condition, a verify operation for reading data from selected cell transistors is performed. The verify operation includes program recovery (stage 306), verify read (stage 307), and Y-scan (stage 308). The program recovery is a process of converting a voltage of a bit line into a predetermined value for data read and includes discharging and precharging the bit line. The verify read is a process of reading and latching data of the bit line and may include development for reading the data of the bit line, bit line sensing, data latching, and bit line recovery. The Y-scan is a process of sequentially scanning and outputting data read from memory cells, i.e., bit lines of a selected page.
When at least one cell transistor among the selected cell transistors is not programmed sufficiently, the above-described programming process (including the bit line setup, the program execution, and the verify read) is repeated according to a predetermined program loop in stages 309 and 310. Here, a high voltage used in a subsequent program loop, e.g., a second program loop is set to be higher (for example, 0.4 V higher) than that used in a current program loop, e.g., a first program loop.
In the conventional programming operations, the Y-scan is executed after the verify read is completed. In this case, as described above, because the program operation is performed in a relatively short time, the Y-scan time is not ignorable. Moreover, because the verify read is repeated when the programming process is repeated, the Y-scan time may not be ignored.

Programming methods for a nonvolatile memory device using a Y-scan operation during a verify read operation


This invention relates to a novel use of IL-1□-ligand/IL-1 receptor disrupting compounds (herein referred to as “IL-1beta Compounds”); such as small molecular compounds disrupting IL-1□ ligand—IL-1 receptor interaction, IL-1□ antibodies or IL-1 receptor antibodies, e.g. IL-1□ binding molecules described herein, e.g. antibodies disclosed herein, e.g. IL-1□ binding compounds or IL-1 receptor binding compounds, and/or RNA compounds decreasing either IL-1□ ligands or IL-1 receptor protein levels, in the treatment and/or prevention of auto-inflammatory syndromes, e.g. Juvenile rheumatoid arthritis or adult rheumatoid arthritis syndrome and to methods of treating and/or preventing auto-inflammatory syndromes, e.g. Juvenile rheumatoid arthritis or adult rheumatoid arthritis syndrome, in mammals, particularly humans.

This invention relates to a novel use of IL-1β-ligand/IL-1 receptor disrupting compounds (herein referred to as "IL-1beta Compounds"); such as small molecular compounds disrupting IL-1β ligand—IL-1 receptor interaction, IL-1β antibodies or IL-1 receptor antibodies, e.g. IL-1β binding molecules described herein, e.g. antibodies disclosed herein, e.g. IL-1β binding compounds or IL-1 receptor binding compounds, and/or RNA compounds decreasing either IL-1β ligands or IL-1 receptor protein levels, in the treatment and/or prevention of auto-inflammatory syndromes, e.g. Juvenile rheumatoid arthritis or adult rheumatoid arthritis syndrome and to methods of treating and/or preventing auto-inflammatory syndromes, e.g. Juvenile rheumatoid arthritis or adult rheumatoid arthritis syndrome, in mammals, particularly humans.
Interleukin-1β (IL-1beta or IL-1β or Interleukin-1β have the same meaning herein) is a potent immuno-modulator which mediates a wide range of immune and inflammatory responses. Inappropriate or excessive production of IL-1β is associated with the pathology of various diseases and disorders, such as septicemia, septic or endotoxic shock, allergies, asthma, bone loss, ischemia, stroke, traumatic brain injury, rheumatoid arthritis and other inflammatory disorders. Antibodies to IL-1β have been proposed for use in the treatment of IL-1 mediated diseases and disorders; see for instance, WO 95/01997 and the discussion in the introduction thereof and WO 02/16436, the content of which is incorporated by reference.

Methods of treating vascular disease using an IL-1beta Antibody


In a method for leaching gold from copper sulfides, the sulfide ores are first subjected to leaching of copper, thereby producing a leaching residue having 7.9% or less of the copper content. This leaching residue is mixed with a leach liquor, which contains the chloride ion and ferric ion and has 1.9 or less of pH. Gold and copper can be effectively leached from the copper sulfide ores. Ordinarily used oxidizing reagents such as hydrogen peroxide or nitric acid are not used. The gold, copper and iron can, therefore, be leached in a single process and by using an identical leaching liquor. The rate of gold leaching reaction can be enhanced by the co-presence of either copper or bromide ion or both together with the chloride and iron ion.

1. Field of Invention
The present invention relates to a method for leaching of gold for recovering the gold from sulfide ores and silicate ores containing gold. More particularly, the present invention relates to the leaching method of gold in an aqueous solution under atmospheric pressure and at a temperature lower than the boiling temperature.
2. Background Technique
Copper sulfide ores and silicate ores, which are accompanied with the copper sulfide ores, contain gold. Methods for recovering the gold from such ores are largely classified into two types. One of the methods involves heating to high temperature of 1000° C. or more. Specifically, the copper sulfide ores and the silicate ores containing gold are melted together with iron sulfide. Silicate ore may be added as a flux agent. As a result, Cu2S referred to as the matte and slag mainly composed of iron oxide and silicate and containing impurities are formed. The matte is reduced at high temperature to yield low-purity metallic copper, referred to as crude copper. The crude copper is subjected to the electrolytic decomposition to yield the metallic copper having purity of 99.99% or more. Gold contained in the raw material behaves in the same manner as the copper during the production of metallic copper. Gold and the other precious metals are recovered in the precipitates referred to as "electrolytic copper sludge" during the electrolytic decomposition process.
The electrolytic copper sludge is melted together with lead so as to concentrate the precious metals in the lead. The lead, in which the precious metals are concentrated, is oxidized to remove the lead. A silver plate containing these precious metals, such as gold, referred to as a prototype silver plate, is produced. The prototype silver plate is subjected to electrolytic decomposition to electrolytically deposit the refined silver and to yield the precipitates referred to as the electrolytic silver sludge, which contains the precious metals. These precipitates are treated by nitric acid or the like to dissolve the precious metals other than gold. The resultant solid gold is melted to produce a prototype gold plate, which is gold having low purity. The prototype gold plate is subjected to electrolytic decomposition to recover the high-purity gold. High temperature exceeding 1000° C. is necessary in this method. Since the main purpose of this method is to produce metallic copper, and gold is recovered as a byproduct, the treating process until the gold recovery is disadvantageously very long.
The other method of recovering gold is to bring the copper sulfide ore or the like into contact with a solution which contains a complex-forming compound, such as cyanide, thiourea, and thiosulfuric acid, which are liable to form a gold compound. These complex-forming compounds are caused to react with the gold and the reacted gold is then dissolved in the solution. The dissolved gold is adsorbed on the surface of activated carbon. High temperature is not necessary and the recovering process is short in this process. However, when such metallic elements as copper and iron are co-present with gold, these metallic elements form complex compound, which uses up the complex-forming agents. It is, therefore, advisable to preliminarily remove the metallic elements other than gold to an appropriate level. "REVIEW OF GOLD EXTRACTION FROM ORES", S. R. La BROOY, H. G. LINGE and G. S. Walker, Minerals Engineering, Vol. 7, No. 10, pp 1231-1241 proposes separate treatments of the gold and the metals other than the gold.
Gold and a halogen-group element form a complex compound, which is liable to dissolve in the aqueous solution. This property is utilized, for example, in U.S. Pat. No. 5,487,819, which proposes to leach gold in an aqueous solution containing a halogen-group element. An oxidizing reagent is necessary in this process to oxidize the metallic gold to the gold ions. Usually, nitric acid, hydrogen peroxide, or chlorine having the standard oxidation reduction potential of more than +900 mV are used as the oxidizing element. Since almost all of the metallic elements contained in the ore are oxidized under the presence of the oxidizing agent having the high oxidation-reduction potential mentioned above, more of oxidizing agent is consumed for oxidizing the metallic elements other than gold than that for recovering oxidizing gold (c.f., "Establishment of Wet Processing Technique for Copper Sludge", Akinori, TORAIWA, Yoshifumi, ABE, "Shigen to Sozai" Vol. 116 (2000), No. 6, pp 484-492.


A storage device includes a connector with first to ninth pins, a serial advanced technology attachment (SATA) control chip, a universal serial bus (USB) control chip, and a storage chip. Voltage terminals of the SATA control chip, the USB control chip, and the storage chip are connected to the first pin of the connector. Second, third, fifth, and sixth signal terminals of the SATA control chip are connected to the fifth pin, the sixth pins, the eighth pin, and the ninth pin of the connector, respectively. Output terminals of the SATA control chip and the USB control chip are connected to a signal terminal of the storage chip. Second, third, fifth, sixth, eighth, and ninth signal terminals of the USB control chip are connected to the second pin, the third pin, the fifth pin, the sixth pin, the eighth pin, and the ninth pin of the connector, respectively.

1. Technical Field
The present disclosure relates to a storage device.
2. Description of Related Art
At present, universal serial bus (USB) devices and serial advanced technology attachment dual in-line memory module (SATA DIMM) devices are widely used for storing data in computer systems. However, the USB devices are convenient to carry but they have less storage capacity. The SATA DIMM devices have large storage capacity but they need to be inserted into memory slots and connected to SATA connectors of a motherboard, to receive voltages and control signals. When the number of the SATA connectors or the memory slots of the motherboard are limited, the SATA DIMM devices will not be used, and further the SATA DIMM devices are not convenient to carry. Therefore, there is room for improvement in the art.

HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD.


Provided herein are formulations, processes, solid forms and methods of use relating to salts of and solid forms comprising free base or salts of (S)-2-(2,6-dioxopiperidin-3-yl)-4-((2-fluoro-4-((3-morpholinoazetidin-1-yl)methyl)benzyl)amino)isoindoline-1,3-dione.

Alternative solid forms of pharmaceutical compounds have emerged as a possible approach to modulate or enhance the physical and chemical properties of drug products. The identification and selection of a solid form of a pharmaceutical compound are complex, given that a change in solid form may affect a variety of physical and chemical properties, which may provide benefits or drawbacks in processing, formulation, stability, bioavailability, storage, handling (e.g., shipping), among other important pharmaceutical characteristics. Useful pharmaceutical solid forms include crystalline solids and amorphous solids, depending on the product and its mode of administration. Amorphous solids are characterized by a lack of long-range structural order, whereas crystalline solids are characterized by structural periodicity. The desired class of pharmaceutical solid depends upon the specific application; amorphous solids are sometimes selected on the basis of, e.g., an enhanced dissolution profile, while crystalline solids may be desirable for properties such as, e.g., physical or chemical stability (see, e.g., S. R. Vippagunta et al., Adv. Drug. Deliv. Rev., (2001) 48:3-26; L. Yu, Adv. Drug. Deliv. Rev., (2001) 48:27-42).
Notably, it is not possible to predict a priori if crystalline forms of a compound even exist, let alone how to successfully prepare them (see, e.g., Braga and Grepioni, 2005, "Making crystals from crystals: a green route to crystal engineering and polymorphism," Chem. Commun.:3635-3645 (with respect to crystal engineering, if instructions are not very precise and/or if other external factors affect the process, the result can be unpredictable); Jones et al., 2006, Pharmaceutical Cocrystals: An Emerging Approach to Physical Property Enhancement," MRS Bulletin 31:875-879 (at present it is not generally possible to computationally predict the number of observable polymorphs of even the simplest molecules); Price, 2004, "The computational prediction of pharmaceutical crystal structures and polymorphism," Advanced Drug Delivery Reviews 56:301-319 ("Price"); and Bernstein, 2004, "Crystal Structure Prediction and Polymorphism," ACA Transactions 39:14-23 (a great deal still needs to be learned and done before one can state with any degree of confidence the ability to predict a crystal structure, much less polymorphic forms)).
The type of salt form of a particular active pharmaceutical ingredient may affect certain properties of the active pharmaceutical ingredient. These properties include solubility, stability, and bioavailability.
The variety of possible solid forms, including both free base forms and salt forms, creates potential diversity in physical and chemical properties for a given pharmaceutical compound. The discovery and selection of solid forms are of great importance in the development of an effective, stable and marketable pharmaceutical product.

Solid forms comprising (S)-2-(2,6-dioxopiperidin-3-yl)-4-((2-fluoro-4-((3-morpholinoazetidin-1-yl)methyl)benzyl)amino)isoindoline-1,3-dione and salts thereof, and compositions comprising and methods of using the same


A mains power wire connection assembly (100) using a button to push a first wire and a second wire to move toward the direction of clamping slots, and the inner walls of the clamping slots puncture the first wire and second wires and clamp the same. The button and the insulation body are locked and fixed with respect to each other.

With continuous development of the economy and continuous advancement of the science and technology, abundant electrical products are available in people's lives. The wide use of electrical products increases the demand on electricity resources, which creates good conditions for development of the mains power wire industry, and therefore improves popularity of mains power wires.
It is commonly known that a mains power wire is a cable whose transmission voltage ranges from 110 to 380 voltages. When a mains power wire is installed outdoors, because mains power wires on the market are generally available in rolls and a length of each roll of wires is relatively fixed, outdoor mains power wires need to be joined and fixed for long-distance electrical power transmission. Likewise, when electrical power from a mains power wire that supplies electrical power outdoors needs to be transferred indoors for people to use an electrical product, the outdoor mains power wire and an indoor mains power wire need to be joined and fixed. Furthermore, during installation of various indoor electrical products, mains power wires are also frequently joined and fixed. At present, a common method for joining and fixing mains power wires is performed as follows: first, an operator removes, by using a cutting tool, insulation layers of mains power wires that are to be joined, so as to expose conductors; next, the operator twists the conductors that are to be joined, so as to implement an electrical connection between the mains power wires; and finally, the operator wraps a twist joint of the conductors with an insulating tape for sealing, so as to prevent people from being electrically shocked accidentally and to achieve a certain fixing effect.
However, the above process of joining and connecting the mains power wires involves operations of removing the insulation layers of the mains power wires, twisting the conductors of the mains power wires, and wrapping the twist joint of the conductors with the insulating tape. On one hand, this makes it very complex to join and connect the mains power wires, increases a load of the operator, and consequently reduces operational efficiency. On the other hand, the conductor is likely to be damaged when the operator removes the insulation layer, which results in waste of the mains power wires. Furthermore, when the conductors of the mains power wires are twisted together, tensile performance of the twist joint of the conductors is reduced because of twisting and deformation of the conductors, resulting in that the electrical connection between the mains power wires is not reliable. The twist joint of the mains power wires are fixed by wrapping the insulating tape; this mechanical fixing is not firm and is likely to break accidentally.
Therefore, a mains power wire connection assembly, a connector, and a connection method are urgently required to address the foregoing defects.

Mains power wire connection assembly and connection method


A method and device for the rapid quantification of biomolecules (320) present in a nanochannel (210) is claimed. In particular, the present invention relates to a novel concept of liquid actuation and selectively functionalized surfaces in a nanochannel that create a concentration gradient of transitory immobilized biomolecules (340) across the nanochannel. The present concept enables the quantification of biomolecular interactions of interest (320).

Nanofluidic biosensors are defined as fluidic systems with nanometer-sized confinements and/or lateral apertures, which are used to quantify the presence of biomolecules in a solution. A majority of the current nanofluidic biosensor developments are intended for bioengineering and biotechnology applications. In the scope of this invention, biosensors are used to quantify the presence of biomolecules in solution for in vitro diagnostic applications.
Swiss patent application CH 01824/09 discloses biosensors with lateral apertures for the detection of biomolecular interactions and PCT application IB2010/050867 discloses their use with simple optical systems. The diffusion of biomolecules in these configurations are slow and require either long waiting times to attain stable measurement conditions or highly concentrated solutions for the observation of the biomolecular interactions.
Biomarkers, also called biological markers, are substances used as specific indicators for detecting the presence of biomolecules. It is a characteristic that is objectively measured and evaluated as an indicator of biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention.
Current practices for the detection of specific biomolecules can be divided in two categories: (a) the labeled techniques and (b) the label-free techniques.
Among the labeled techniques, the widely used are fluorescence, colorimetry, radioactivity, phosphorescence, bioluminescence and chemiluminescence. Functionalized magnetic beads can also be considered as labeling techniques. Labeled techniques advantages are the sensitivity in comparison to label-free methods and the molecular recognition due to specific labeling.
Among the label-free techniques, the widely used are electrochemical biosensors, referring to amperometric, capacitive, conductometric or impedimetric sensors, which have the advantage of being rapid and inexpensive. They measure the change in electrical properties of electrode structures as biomolecules become entrapped or immobilized onto or near the electrode, but all these concepts lack molecular specific contrast, sensitivity and reliability.
Enzyme linked immunosorbent assay (ELISA) is an important biochemical technique mainly used to detect the presence of soluble biomolecules in serum, and thus is widely used as diagnostic tool in medicine and quality control check in various industries. ELISA analysis are however expensive, require large amounts of solution and is time consuming.
The other important technologies for biomolecular diagnostics are Western and Northern blots, protein electrophoresis and polymerase chain reaction (PCR). However, these methods require highly concentrated analytes and do not allow high throughput samples testing.

Rapid quantification of biomolecules in a selectively functionalized nanofluidic biosensor and method thereof


An EGR control method and unit for an internal combustion engine includes an EGR passage configured to recirculate a portion of an exhaust gas from an exhaust system to an intake system. An EGR valve, disposed in the EGR passage, is configured to control an amount of EGR, and an index calculator is configured to calculate a surge-increase index according to a variance in rotation of the engine. A detector is configured to compare the surge-increase index with a determination threshold to detect a surge increase, an adjuster is configured to adjust a correction value relative to a target amount of the EGR according to an output of the detector, and a target-amount calculator is configured to calculate the target amount of the EGR by subtracting the correction value from a reference target amount of the EGR determined based upon an engine operating condition.

1. Field of the Invention
The present invention relates to an EGR (Exhaust Gas Recirculation) control unit for an internal combustion engine, and more particularly, the present invention relates to an EGR control unit that avoids an increase in a surge (torque fluctuations).
2. Description of Related Art
In Japanese Unexamined Patent Publication No. 2002-048011, surge level index calculating means is provided for calculating a surge level index to detect a surge occurring in the engine on the basis of information related to an angular velocity of an engine crankshaft, and surge-level determining means is provided for determining the surge level from a comparison between the surge level index and a determination threshold. Accordingly, an opening degree of an EGR valve is controlled on the basis of the change in the surge level and the surge level.
In Japanese Unexamined Patent Publication No. 2002-048011, for controlling the opening degree of the EGR valve, particularly a step motor type EGR valve, a basic amount of EGR based on an engine speed and an engine load is multiplied by a limit value based on a target value which is increased/decreased on the basis of a change in a surge level and the surge level, thereby to calculate the amount of the EGR. Then, based on the amount of EGR, a motor target position of the step motor type EGR valve is determined. The step motor type EGR valve is driven according to a comparison result between the motor target position and a current motor position.
Also in Japanese Unexamined Patent Publication No. 2000-199454, an atmospheric pressure and an intake negative pressure are monitored, respectively and a ratio of an exhaust pressure to an intake pressure is calculated and divided by the flow of EGR in order to calculate an effective opening area, thereby estimating a shift in an opening area of the EGR valve (initial stage/degradation).
When the surge increase is detected to correct the amount of the EGR, it is difficult to properly determine a correction amount of feedback unless different correcting methods are used between a case that a tolerance ratio of the EGR due to an environmental change is reduced and a case that the opening area of the EGR valve is shifted (initial stage/degradation). For this reason, in the multiplication correction (gain correction) disclosed in Japanese Unexamined Patent Publication No. 2002-048011, it is possible to deal only with an environmental change. However, it is difficult to deal with the shift of the opening area of the EGR valve. When an operating point is shifted, the surge increase continues until the surge level determination is performed again.
As another method of correcting the opening area of the EGR valve, in Japanese Unexamined Patent Publication No. 2000-199454, the atmospheric pressure and the intake negative pressure are monitored respectively, thereby estimating the shift of the opening area of the EGR valve. However, it is necessary to provide an atmospheric pressure sensor and an intake negative pressure sensor, thus increasing complexity and cost.

EGR control unit and method for an internal combustion engine


System and method aspects for testing a hierarchical storage management (HSM) system extension of a data processing system are provided. In a system aspect, the system for testing includes a script file mechanism for providing serialized system calls from processes of at least a pseudo device driver of the data processing system, and a compiled test engine means for performing the serialized system calls of the script file. The system calls from processes further include parallel processes of a file system and a pseudo device driver. In a method aspect, the method includes providing a test engine compiled for at least one operating system platform of the data processing system, and performing a test script with the test engine for serializing system calls from parallel processes of the file system and pseudo device driver.

In some data processing systems, files are stored according to a hierarchical storage management (HSM) file system. For example, an HSM file system is often employed in systems with a version of the UNIX operating system. Typically, operating system HSM extensions are required to support the HSM file system. The specific functions required through the extensions often vary from one operating system implementation, e.g., one UNIX implementation, to another. For systems operating according to an implementation of the UNIX operating system, the extensions that provide the support normally include a pseudo device driver extension and virtual file system function.
Test facilities are often employed to monitor the functionality of the HSM file system extension to identify any possible problems or errors in the extension. In typical systems, testing takes the form of a black box facility. In the black box approach, the operating system extensions normally are not tested on an isolated basis. Rather, testing occurs as the rest of the system, e.g., background processes/daemons, etc., occur and in parallel with the performance of file system operations. In the multiprocessing environment supported by UNIX platforms, processes run concurrently without regard to one another. Difficulty in reproducing specific sequences of system calls across concurrent processes arises, since operating systems normally schedule system calls according to factors, including the other activity on the system, that are independent from the testing. Unfortunately, defects are therefore often difficult to reproduce, as they may be related to a particular sequence of system calls that the black box approach is unable to identify. Thus, the granularity of the testing is less than optimal for determining defects in the extensions supporting the HSM file system.
Accordingly, what is needed is a test facility that remains independent by capably exercising system call interfaces in any sequence and with any combination of parameters.

Method and system for facilitating hierarchical storage management (HSM) testing

International Business Machines Corporation


When a minimum thickness of a part where an outer ring raceway is provided on a middle portion in the axial direction of an outer ring is h, and a diameter of each rolling element is Da, the relationship 0.4 Da≦h 0.8 Da is satisfied. As a result, even when the outer ring 4a is fixed in a transmission case of low-rigidity, elastic deformation of the outer ring can be prevented without needlessly increasing the thickness h of the outer ring.

1. Field of the Invention
The present invention relates to ensuring durability of rolling bearings for rotatably supporting rotating members of various rotating machinery and equipment such as pulleys on automobile alternators and belt-type continuously variable transmissions, and gears and the like constituting manual transmissions and automatic transmissions.
2. Description of the Related Art
Firstly, rolling bearings using a low-viscosity CVT fluid (including ATF compatible oil), and incorporated into transmission cases of low rigidity are described.
As disclosed in, for example, Japanese Examined Utility Model Publication No. H8-30526 and the like, a variety of belt-type continuously variable transmissions has been heretofore designed as speed changing units in automatic transmissions for automobiles, and some of these have been employed in practice. FIG. 1 shows the basic structure of such a belt-type continuously variable transmission in simplified form. This belt-type continuously variable transmission has an input rotating shaft 1 and an output rotating shaft 2 which are mutually arranged in parallel. These rotating shafts 1 and 2 are rotatably supported within a transmission case (not shown in drawings), which is a fixed part, by respective pairs of rolling bearings 3.
As shown in detail in FIG. 2, each rolling bearing 3 has a concentric outer ring 4 and an inner ring 5. The outer ring 4 has an outer ring raceway 6 on an inner peripheral face, and the inner ring 5 has an inner ring raceway 7 on an outer peripheral face. A plurality of rolling elements 8 are rotatably provided between the outer ring raceway 6 and the inner ring raceway 7 while being held by a retainer 9. In the rolling bearings 3 which are respectively constructed in this manner, the outer ring 4 is fixed to the inside of part of the transmission case, and the inner ring 5 is fixed on the outside of the input rotating shaft 1 or the output rotating shaft 2. Both of these rotating shafts 1 and 2 are rotatably supported within the transmission case by this construction. The outer ring 4, the inner ring 5, and the rolling elements 8 manufactured of general class 2 bearing steel (SUJ2), have conventionally been used for each rolling bearing 3.
Of the rotating shafts 1 and 2, the input rotating shaft 1 is driven to rotate by a drive source 10 such as an engine via a start clutch 11 such as a torque converter or electromagnetic clutch. Furthermore, a drive pulley 12 is provided at a part positioned between the pair of rolling bearings 3 in the middle portion of the input rotating shaft 1, so that this drive pulley 12 and the input rotating shaft 1 rotate synchronously. By displacing one drive pulley plate 13a (on the left in FIG. 1) in the axial direction with a drive actuator 14, the space between the pair of drive pulley plates 13a and 13b constituting the drive pulley 12 can be freely adjusted. That is to say, the width of the groove in the drive pulley 12 can be freely increased or decreased with the drive actuator 14.
On the other hand, a driven pulley 15 is provided at a part positioned between the pair of rolling bearings 3 in the middle portion of the output rotating shaft 2, so that this driven pulley 15 and the output rotating shaft 2 rotate synchronously. By displacing one driven pulley plate 16a (on the right in FIG. 1) in the axial direction with a driven actuator 17, the space between the pair of driven pulley plates 16a and 16b constituting the driven pulley 15 can be freely adjusted. That is to say, the width of the groove in the driven pulley 15 can be freely increased or decreased with the driven actuator 17. An endless belt 18 is spanned between the driven pulley 15 and the drive pulley 12. For this endless belt 18, a metal belt is used.
In the belt-type continuously variable transmissions constructed as described above, the drive transmitted from the drive source 10 to the input rotating shaft 1 via the start clutch 11 is transmitted from the drive pulley 12 to the driven pulley 15 via the endless belt 18. Heretofore as the endless belt 18, there is known one wherein drive is transmitted in the push direction, and one wherein drive is transmitted in the pull direction. In either case, the drive transmitted to the driven pulley 15 is transmitted to a drive wheel 21 from the output rotating shaft 2 via a reduction gear train 19, and a differential gear 20. When changing the gear ratio between the input rotating shaft 1 and the output rotating shaft 2, the groove width of the pulleys 12 and 15 is increased or decreased while changing the relationship between the two.
For example, to increase the speed reduction ratio between the input rotating shaft 1 and the output rotating shaft 2, the width of the groove in the drive pulley 12 is increased, and the width of the groove in the driven pulley 15 is decreased. As a result, the diameter of the parts of the pulleys 12 and 15 spanned by part of the endless belt 18 is decreased on the pulley 12, and increased on the pulley 15, and speed reduction is performed between the input rotating shaft 1 and the output rotating shaft 2. Conversely, to increase the speed increasing ratio between the input rotating shaft 1 and the output rotating shaft 2 (decrease the speed reduction ratio), the width of the groove of the drive pulley 12 is decreased, and the width of the groove of the driven pulley 15 is increased. As a result, the diameter of the parts of the pulleys 12 and 15 spanned by part of the endless belt 18 is increased on the pulley 12, and decreased on the pulley 15, and speed increase is performed between the input rotating shaft 1 and the output rotating shaft 2.
When operating the belt-type continuously variable transmission constructed and operating as described above, lubricating oil is supplied to each moving part to lubricate each moving part. The lubricating oil employed in the belt-type continuously variable transmission is CVT fluid (including ATF compatible oil). The reason for this is to increase and stabilize the coefficient of friction of the frictional engagement parts of the metal endless belt 18 and the drive and driven pulleys 12 and 15. The CVT fluid is circulated to the frictional engagement parts at a flow rate of at least 300 cc per minute to lubricate these frictional engagement parts. Moreover, part of the CVT fluid is passed through the interior of each of the rolling bearings 3 (for example, at a flow rate of at least 20 cc per minute) to lubricate the rolling contact parts of the rolling bearings 3. Therefore there is a high possibility that foreign matter such as wear particles generated by wear accompanying frictional between the endless belt 18 and the pulleys 12 and 15, and gear dust generated by friction in the reduction gear train 19, will become mixed with the CVT fluid and enter the interior of these rolling bearings 3. Such foreign matter may damage the rolling contact parts of the rolling bearings 3, and reduce their durability.
Therefore, heretofore the bearing size of the rolling bearings 3 has been increased, or the diameter Da of the rolling elements 8 has been increased, to increase the basic dynamic load rating of the rolling bearings 3, and to provide a margin for the life of the rolling bearings 3. However, when in this manner the diameter Da of the rolling elements 8 is increased to maintain the basic dynamic load rating, a thickness T of the outer ring 4 must be reduced (made thinner) to reduce the size and weight of the belt-type continuously variable transmission. Furthermore, when the rigidity of the transmission case securing the outer ring 4 is low, if the thickness T of this outer ring 4 is reduced in this manner, elastic deformation of the outer ring 4 occurs readily, and an excessive bending stress is applied to the outer ring 4 accompanying the deformation, so that there is a possibility that the life of the rolling bearings 3 will be reduced.
For example, in the Proceedings of the Tribology Conference of the Japanese Society of Tribologists (Morioka 1992-10) E-33, pp 793-796, it is disclosed that the life of this rolling bearing was reduced by ¼ to ⅕ when the rolling bearing was operated with a bending stress of 70 MPa applied to the raceway ring, in comparison to the case where a bending stress was not applied. Furthermore, it is disclosed that, in order to prevent such a reduction in life, manufacture of the raceway ring from a material wherein a residual compression stress has been applied is effective. However, in order to employ the material wherein such a retained compression stress has been applied, carburized steel must be employed in the raceway ring, and mechanical processes such as shot-peening and the like must be applied to the raceway face of the raceway ring, with the possibility of increased cost.
Recently, in order to ensure the efficiency of belt-type continuously variable transmissions, to suppress noise generated during operation, and to suppress wear of the drive and driven pulleys 12 and 15, and the endless belt 18, the use of a fluid of lower viscosity is under consideration as a CVT fluid. In this case, if standard rolling bearings are employed as the rolling bearings 3 to support the input and output rotating shafts 1 and 2, the possibility of premature flaking is considered to increase. That is to say, the action of vibration in the radial and axial directions accompanying belt fluctuations exacerbates elastic deformation of the outer ring 4 and the inner ring 5, and an excessive bending stress is applied to the outer ring 4 and the inner ring 5. Accompanying this deformation and excessive bending stress, metal-to-metal contact based on sliding, occurs more readily in the rolling contact parts between the outer ring raceway 6 and the inner ring raceway 7, and the rolling contact surfaces of the rolling elements 8, and the possibility of premature flaking of the outer ring raceway 6, the inner ring raceway 7, and the rolling contact surfaces of the rolling elements 8 increases due to such metal-to-metal contact.
That is to say, there are cases where the temperature of the rolling bearing 3 during operation of the belt-type continuously variable transmission may exceed 100° C. At this time the kinetic viscosity of the CVT fluid which enters the interior of the rolling bearing 3 and lubricates the rolling contact parts of the rolling bearing 3 is considerably low at 10 mm2 per second or less. Moreover, there is also a possibility of a tendency for the amount of CVT fluid supplied to the rolling contact parts to become insufficient. Furthermore, when the rigidity of the transmission case, being the fixed part, is low, the outer ring 4 fixed to the transmission case is readily elastically deformed, and sliding based on differential movement, revolution, and spinning of the rolling elements 8 occurs readily in the rolling contact parts accompanying this deformation. As a result, together with the lack of CVT fluid as described above, the oil film on the rolling contact parts readily breaks up. When the oil film breaks up in such a manner, the outer ring raceway 6 and the rolling contact surfaces of the rolling elements 8 enter an activated state wherein surface fatigue associated with, for example, hydrogen embrittlement flaking due to hydrogen penetration, and metal-to-metal contact, is accelerated, and the possibility of premature flaking increases.
On the other hand, according to Hertz' theory of elastic contact, the maximum shear stress under rolling contact is calculated to occur at a depth from the raceway face of approximately 2% of the diameter of the rolling element. In this case, the thickness of the raceway ring wherein the maximum shear stress occurs is calculated as being semi-infinite. On the other hand, in the case of a standard JIS name and number's rolling bearing, the thickness of the raceway ring tends to be set approximately ten times the depth from the raceway face to the position where the maximum shear stress occurs, that is to say, approximately 20% of the diameter of the rolling element 8. The reason for this is that, when the raceway ring is fixed to a highly rigid part, if the thickness of this raceway ring is approximately 20% of the diameter of the rolling element, the Hertz' theory of elastic contact wherein the thickness of this raceway ring is considered as semi-infinite is established. Moreover, it is considered that experimentally sufficient durability can be maintained. Therefore, in the case of the rolling bearing 3 incorporated in the belt-type continuously variable transmission, if the rigidity of the transmission case is low, the thickness of the outer ring 4 fixed to this transmission case must be increased (made thicker) to ensure durability of the rolling bearing 3. However, simply increasing the thickness of the outer ring 4 in this manner invites increased weight associated with increased size, and increased rolling resistance. Therefore it is not desirable.
In Japanese Unexamined Patent Publication No. H10-37951, there is disclosed an invention for improving the permissible high-speed performance of rolling bearings used for machine tools, by increasing the thickness of the outer ring in comparison to the thickness of the inner ring. That is to say, a construction is disclosed wherein ceramic rolling elements are used to thereby reduce the centrifugal force applied to the outer ring, being the fixed raceway ring. Moreover, in order to reduce the centrifugal force generated in the inner ring, being the rotating raceway ring, the thickness of this inner ring is made 2.5 mm to 4.0 mm, and the thickness of the outer ring is 2.0 to 2.75 times the thickness of the inner ring. However, with this structure, the purpose of making the thickness of the outer ring greater than the thickness of the inner ring is simply to reduce the centrifugal force by reducing the thickness of the inner ring, and not to prevent elastic deformation of the outer ring fixed to the low-rigidity part. Moreover, since the rolling elements are made of ceramic, increased materials costs and machining costs cannot be avoided. Furthermore, since the thickness of the outer ring is excessive, the rolling contact surfaces of the rolling elements are readily damaged, as described later.
Next is a description of a rolling bearing fixed to an alternator having a low-rigidity housing made for example from aluminum alloy.
In various auxiliary equipment having as a power source the drive engine of an automobile, a rotating shaft is rotatably supported in relation to the housing, and a driven pulley is fixed to one end of this rotating shaft on a portion projecting from the housing. The various auxiliary equipment can be freely driven by transmitting the rotation of the engine crankshaft to this driven pulley via an endless belt. FIG. 3 shows an example of an alternator which generates electric power necessary for an automobile, being one of such various auxiliary equipment. In this alternator 101 a rotating shaft 103 is rotatably supported inside a housing 102 made from a light metal such as aluminum alloy, by a pair of rolling bearings 104. Each of these rolling bearings 104 comprises an inner ring 106 having an inner ring raceway 105 formed on an outer peripheral surface, an outer ring 108 having an outer ring raceway 107 formed on an inner peripheral surface, and a plurality of balls 109 being rolling elements, rotatably arranged between the inner ring raceway 105 and the outer ring raceway 107.
Moreover, a rotor 110 and a commutator 111 are provided in the middle portion of the rotating shaft 103. Furthermore, a driven pulley 112 is fixed to an end part of the rotating shaft 103 projecting from the housing 102. With the housing 102 fixed to the engine (not shown in drawings), an endless belt (not shown in drawings) is wrapped around the driven pulley 112, so that the rotation of the crankshaft of the engine can be freely transmitted to the rotating shaft 103 via the endless belt. Moreover, a stator 113 is fixed to a part surrounding the rotor 110 on the inside of the housing 102. In the alternator 101 constructed in this manner, the rotating shaft 103 provided with the rotor 110 is rotated by the rotation of the engine, and electric current is generated in the stator 113 facing this rotor 110.
When the alternator 101 constructed as described above is in use, while the inner rings 106 constituting the rolling bearings 104 rotate, a radial load is continuously applied in the same direction to the inner rings 106 based on the tension of the endless belt. When such a radial load is applied to the outer rings 108 via the balls 109, and the rigidity of the housing 102 securing the outer rings 108 is low, there is a possibility that the outer rings 108 may elastically deform together with the housing 102. Such elastic deformation of the outer rings 108 is considered to be a cause of damage such as premature flaking of the outer rings 108.
That is to say, it is considered that, when the outer rings 108 elastically deform together with the housing 102 based on the radial load, this radial load is applied to the outer ring 108 as an unbalanced load, and the outer rings 108 vibrate more readily. Under such an unbalanced load and vibration, it becomes more difficult to form an oil film of lubricant such as grease or lubricating oil on the rolling contact parts between the inner ring raceway 105 and the outer ring raceway 107 and the rolling contact surface of each ball 109. Furthermore, if the lubricant contains water, or if moisture penetrates from the outside, there is also a possibility that formation of an oil film on the rolling contact parts will become more difficult. When it becomes difficult to form an oil film on the rolling contact parts in this manner, metal-to-metal contact occurs more readily between the inner ring raceway 105 and the outer ring raceway 107, and the rolling contact surface of the balls 109, and there is a possibility of premature flaking of the inner ring raceway 105, the outer ring raceway 107, and the rolling contact surface of the balls 109.
Inventions are disclosed to prevent such premature flaking in, for example, Japanese Unexamined Patent Publication No. 2001-221238 wherein the constituents of the material of the outer ring are controlled, and in Japanese Unexamined Patent Publication No. H5-98280 wherein the constituents of the grease are controlled. However, with the rolling bearings incorporated into auxiliary equipment (electrical components) for automobiles, such as alternators and electromagnetic clutches, conditions of use have become more severe with the effects of increased temperature and speed due to improvements in engine performance associated with recent technical innovations, and increased loads associated with increase in belt tension. Therefore mere control of the components constituting the rolling bearings and the lubricant is no longer sufficient to accommodate these changes in conditions of use, and the possibility of a reduced life due to premature flaking has appeared.

Abstract: When an outer diameter of an outer ring is D, a width of this outer ring in the axial direction is W, a minimum thickness of a part where the outer ring raceway is provided on a middle portion in the axial direction of the outer ring is h, and a diameter of each ball is Da, the respective dimensions are controlled such that a value K calculated by {(h1.5·W)/(Da1.1·.D0.5)} satisfies the relationship 1.20≦K≦2.00. As a result, sufficient rigidity of the outer ring can be maintained, and early exfoliation based on elastic deformation of the outer ring can be prevented without needlessly increasing the size of the outer ring.


A fish killing and fish tissue sanitizing apparatus includes a tank, a water feed pipe extending to the tank, and an electromechanical transducer in pressure-wave transmitting relationship to the tank for generating ultrasonic pressure waves in water contained in the tank. An electrical signal generator is operatively connected to the transducer for energizing same with an alternating electrical signal. A sensor is in operative contact with water contained in the tank for detecting transient and inertial cavitation occurring within the water in the tank.

With specific reference to fish-farms, existing regulatory authorities recommend no specific method for slaughtering fish and as a result, some or all of the following techniques may be employed:    1) Asphyxiation—suffocating the fish by removal from water. Farmed trout are commonly "harvested" by removal from water into bins in which they suffocate. Fish farmers have started to put live fish into bins containing ice according to Bristol University's Department of Meat Animal Science. The researchers also found when fish were removed from water they can often still feel what is happening to them for almost 15 minutes at low temperatures. The researchers concluded that the practice of suffocating fish on ice could unnecessarily prolong the time to unconsciousness. (Kestin, Wotten & Gregory, 1991.)    2) Bleeding—cutting the fish gills causing death by blood loss. This method may be preceded by stunning the fish in a tank containing carbon-dioxide saturated water. Welfare concerns arise with this stunning method as the "fish try to escape violently" when put into the tank, (Kestin, Apr. 2, 1992). The fish are usually unable to move within one minute and do not lose sensibility for 4-5-minutes. Fish could therefore have their gills cut whilst still conscious if lack of movement was mistaken for unconsciousness. If gill-slitting was carried out unsatisfactorily, it is possible that fish could recover consciousness whilst bleeding. For salmon, bleeding is recommended if the fish are intended to be smoked. This ensures the blood vessels are not readily apparent in the finished product. (Shepherd & Bromage, 1988.)
Norwegian fish farmers slaughter salmon by cutting the main blood vessels located in the head. The fish are then returned to the water where they subsequently weaken and die from blood loss. (Sedgewick, 1988.)    3) Concussion—killing by a blow to the head with a small, hand-held club. This slaughter method can cause instantaneous unconsciousness in the fish if done properly. However, the potential for improper stunning and injury to the fish is considerable. (Kestin, Apr. 2, 1992.)    4) Electrocution—killing by placing fish in a large tank through which electricity is allowed to flow for a few seconds. The electrical current and its frequency has to be at just the right level to stun the fish without burning the tissue. In early trials the system used too much electricity and stunned too few fish to be commercially practical. (Anthony Browne, The Times, May 3, 2003)
The Bristol University research team concluded that currently practiced slaughter methods for farmed fish fall far short of the requirement for instantaneous unconsciousness. Concussion and electrocution methods have been suggested as having the most potential for achieving instantaneous unconsciousness in fish, (Kestin, Wotten & Gregory, 1991).
Currently, following their slaughter, fish are cleaned externally then prepared for market. In its slaughtered state, fish tissue will contain whatever toxic pollutants, parasites, bacterial and viral pathogens it is contaminated with.
It is widely recognized that intensive and stressful conditions, associated with fish farming, can predispose fish to attack from disease and parasitic infection and where diseases such as bacterial septicaemia and gill infections, and bacterial gill disease prevail.
Bacterial diseases are currently treated by the use of antibiotics mixed in with fish feed. Potential human health hazards can arise from the high incidence of farmed-fish disease and its subsequent treatment. Prolonged use of antibiotics in fish can lead to the development of drug-resistant strains of bacteria. It is feared that such drug resistance could then be transferred from fish bacteria to human bacteria in the digestive tract with potentially disastrous results. Many antibiotics that treat fish diseases, such as tetracycline and chloramphenicol, are also used in human medicine. (Shepherd & Bromage, 1998.)
Drug resistance may be unknowingly picked up by a human via the above route. If that person were to fall ill and be treated by a doctor using similar antibiotic, the drug may have been rendered less efficient or ineffective.
Another example, with regard to toxic PCB infestation, farmed salmon are fed from a global supply of fish-meal and fish-oil from small open sea fish which studies show are the source of PCB's (Polychlorinated Biphenyls) in most farmed salmon. In three independent studies scientists tested 37 fish-meal samples from six countries and found PCB contamination in nearly every sample. (Jacobs 2002, Easton 2002, and CIFA 1999.)
Humans can ingest PCB's from eating contaminated fish and there is broad multiple governmental agreement from multiple governmental agencies that consumption of PCB's are expected to cause cancer and alter brain development in humans.

Method for subaqueous ultrasonic catastrophic irradiation of living tissue


A medical needle for endoscopic surgery has an external cannula tube in which a protective element is mounted so that it can be shifted axially against a spring. The distal, front protective surface of the protective element in a forward position projects beyond the sharp tip of the cannula tube and in a rear position is behind this tip. The protective surface of the protective element is transparent and can be observed through an optical system installed in the protective element.

In order to reduce the risk in endoscopic surgery of injury to blood vessels or internal organs through puncture, the so-called Veres needle is used. The Veres needle has a hollow outer cannula that is ground obliquely at its distal end to a sharp, penetrating point. A protective element is mounted in the cannula which can be shifted axially and is a spring element that has a closed, blunt, only slightly arched protective surface at its front, distal end. The protective element function as a tube for the insufflation of gas with an opening mounted on the side behind the distal tip.
The Veres needle preferably is used in endoscopic abdominal surgery to introduce pneumoperitoneum in the first puncture. For this, a small incision is first made in the skin, the Veres needle is then introduced into the subdermal fatty tissue, and the protective element is pressed distally forward through the force of the spring, because the resistance in the subdermal fatty tissue is less than the force of the spring. The blunt protective surface of the protective element projects distally forward over the sharp tip of the hollow cannula and displaces the subdermal fatty tissue bluntly, so that no vascular injuries occur in the subdermal fatty tissue due to the sharp, penetrating tip. If the fascia is reached, the resistance of the tissue increases greatly and becomes greater than the force of the spring that presses the protective element forward. The protective surface of the protective element recedes behind the sharp tip and the latter can now penetrate the fascia. Immediately after penetration of the fascia, the counterpressure of the tissue drops again, so that the force of the spring can then shift the protective element forward, and the protective surface protects the sharp tip in the area of the preperitoneum again. As soon as the peritoneum is reached, the pressure against the tip increases again so that the protective element with the protective surface again is pushed back and the sharp tip can open the peritoneum As soon as the tip slides forward into the abdominal cavity, the protective element again rushes forward under the force of the springs because the free abdominal cavity offers no resistance The blunt protective surface, therefore, protects the vessels and intestine in the free abdominal cavity from injury by the sharp tip.
With the Veres needle, the penetration of the fascia and the peritoneum is recognized in that the protective element is pushed backwards and after penetration again rushes forward. This known Veres needle also has a considerable residual risk. For example, intestinal loops adhering to the wall of the peritoneum and large vessels lying in the area of the retroperitoneum in certain circumstances may not be noticed, because the sharp tip, immediately after penetrating the peritoneum, penetrates these intestinal loops or vessels without the protective element being able to quickly move forward.
This residual risk is reduced by a needle of the nature of the generic terms as recognized in German No. 9,112,976 U1 and similarly in U.S. Pat. No. 4,254,762. In the case of this needle, the protective element that can be shifted in the cannula tube provided with the sharp tip is formed as a tube and has at its distal, front end a translucent, blunt protective surface An optical system is installed in the tubular protective element by which the protective surface can be observed from inside. The protective element, therefore, not only fulfills the function of protection as with the conventional Veres needle, but in addition, makes an optical observation of the tissue layers penetrated possible for the operator of the needle, and thus, the possibility of checking whether the free abdominal cavity is actually reached after penetration of the abdominal wall. In the case of this known needle, however, the distal protective surface of the protective element is constructed as an even front face running vertically to the axis of the cannula. If this even protective surface is applied to the tissue under the pressure of the force of the spring, the tissue will be pressed flat, so that no optical differentiation is then possible between fatty tissue, fascia, and muscle tissue Although this is to be prevented in that during the puncture, the flat protective surface moves back behind the sharp tip of the cannula tube, so that a free space remains between the tip and the protective surface, this free space fills with blood during the puncture, so that differentiating observation is also not improved in this manner.
Furthermore, a trocar is known, see German 4,035,146 C2 , whose penetrating tip is made as a transparent window. An optical system inserted into the trocar shaft allows observation both of the tissue lying directly in front of the tip as well as of the tissue lying to the side of the tip when the trocar tip penetrates. The operator, therefore, can penetrate the tissue in view. This trocar, however, has a relatively large external diameter. In the case of thin needles of only 2-3 mm external diameter, it is difficult to produce a transparent tip with the mechanical properties required for the penetration.
From EP 0,684,016 A2 and EP 0,642,764 A1, a trocar is known in which the distal tip is rounded and transparent. The penetration of the tip into the tissue can be observed via an optical system installed in the trocar. Since the rounded tip of the trocar is not suitable for penetration of the tissue, sharp edges are mounted in the tip which can be moved distally forward beyond the rounded, transparent trocar tip in order to separate the tissue to be penetrated. This produces the disadvantage that in the actual penetration possible by means of the distally extended cutting edges, no observation is possible.
The objective of the invention is to provide a medical needle that has a sharp, penetrating tip in which the risk of injury to vessels and organs by the sharp, penetrating tip is as low as possible.
The surgical needle herein disclosed has a sharp, penetrating tip with a protective element that can be shifted by spring actions whose distal, blunt protective surface is rounded and is optically transparent An optical system is installed in this protective element by which the protective surface can be observed from the inside.
The optical system is mounted in the protective element such that the distal lens of the system is at a distance axially from the transparent protective surface so that a good optical image of the tissue parts lying on the protective surface results. The optical system can be fixed in the protective element or mounted so that it can be changed in the protective element. An exchange mounting has the advantage that the needle can be constructed as a disposable instrument whereas the expensive optical system can be used several times. Also in the case of the disposable instrument, the exchangeability of the optical system may be of advantage because the optical system can be taken out for sterilization of the needle, and must not be exposed to the high sterilization temperatures
The blunt protective surface shields the sharp tip in the distally shifted position of the protective element as well as possible, because the sharp, penetrating tip lies on the cylindrical casing surface of the protective element so that the tip does not project freely in spite of the rounding of the protective surface.
The shapes of the blunt protective surface of the protective element can be made different according to the requirements of different uses. A flat protective surface arched slightly forward provides larger surface bearing on the tissue so that a greater tissue pressure, working against the force of the spring, is exerted on the protective element.
The effect of the changing tissue resistance exploited in the conventional Veres needle can also be used in this constructed.
A more intense arching of the protective surface forward with a smaller curve radius may be advantageous from other perspectives. The smaller curve radius and more intense arching of the protective surface result in lower counterpressure of the tissue on the protective surface and the protective element in the penetration process. The lower pressure of the protective surface on the tissue has the consequence that the tissue becomes less anemic, that is, that the blood is less pressed out of the tissue, in which case the tissue would appear pale. Furthermore, the protective element with the blunt protective surface arched forward can also be intentionally pressed forward and held in the forward position in order to probe forward with the tip in the tissue while viewing, and the sharp, penetrating tip can then be used, with release of the protective element, only when it is assured that the penetration will be without danger.
During the penetration and insertion of the needle, the subdermal fatty tissue first appears yellow When the fascia is reached, it appears white. After penetration of the fascia, the muscle tissue appears red Any vessels lying in front of the tip of the needle can be recognized and avoided. If the preperitoneal fatty tissue is reached, the protective element with the blunt protective surface can intentionally be pressed forward so that the blunt protective surface, independent of the force of the spring, can be kept projecting beyond the sharp tip. The fatty tissue can be penetrated with the blunt protective surface until the protective surface contacts the wall of the peritoneum. The latter can be pressed in with the blunt protective surface without penetration, and stretched (tenting effect). In this way, the peritoneum becomes semitransparent and intestinal loops or vessels adhering to the peritoneum can be recognized.
When it can be assured in this manner that no adhesions are present beneath the peritoneum, the protective element can be released so that it recedes back behind the sharps penetrating tip. The sharp tip then penetrates the peritoneum without risk.


The present invention provides a high-voltage junction field effect transistor (JFET), a method of manufacture and an integrated circuit including the same. One embodiment of the high-voltage junction field effect transistor (JFET) (300) includes a well region (320) of a first conductive type located within a substrate (318) and a gate region (410) of a second conductive type located within the well region (320), the gate region (410) having a length and a width. This embodiment further includes a source region (710) and a drain region (715) of the first conductive type located within the substrate (318) in a spaced apart relation to the gate region (410) and a doped region (810) of the second conductive type located in the gate region (410) and extending along the width of the gate region (410). In place of or addition to the doped region (810), the high-voltage junction field effect transistor (JFET) (300) may includes a conductive field plate (920) located over and extending along the width of the gate region (410).

There are two basic types of transistors, namely Field Effect Transistors (FETs) and bipolar transistors. In general, current is conducted in FETs by charge carriers (e.g., electrons and holes) typically flowing through one type of semiconductor material, either n-type or p-type materials. In bipolar transistors, current passes in series through both n-type and p-type semiconductor materials.
Within the category of FETS, there are two basic types, namely the Metal Oxide Semiconductor (MOS) FET and the Junction FET (JFET). A primary difference between these two types of transistors is that the gate of the MOSFET has a layer of insulating material, typically referred to as gate oxide, between the gate and the other transistor electrodes. Consequently, channel current in a MOSFET is controlled by the application of electric fields across the channel to enhance and deplete the channel region, as operation requires. The gate of the JFET forms a PN junction with the other electrodes of the transistor, which can be reverse biased by the application of a predetermined gate voltage. Thus, the gate PN junction can be utilized to control the channel current by varying the extent of a depletion region to selectively dimension the current-carrying channel.
There are two different types of JFETs, an n-channel JFET and a p-channel JFET. In the n-channel JFET, carriers are electrons, and in the p-channel JFET carriers are holes. Additionally, the n-channel JFET includes an n-type channel and a p-type gate region, whereas the p-channel JFET includes a p-type channel and an n-type gate region.
JFETs are often employed in start-up circuits (e.g., for telecom and datacom equipment in central offices, PBXs, and servers) where a small current (mA) is supplied from a high (e.g., about 100 V) DC. One example of a schematic for a 110V start-up JFET for a telecom device is shown in FIG. 1. The JFET 100 includes a drain 110, a source 130, and a gate 170. The drain 110 is coupled to an input voltage (Vin) 120, the source 130 coupled to a supply voltage (Vdd) 140 and a bypass capacitor 150 via a voltage drop component 160, and the gate 170 is coupled to a gate control 180.
At the beginning of start-up, the gate control 180 provides a low-impedance path between gate 170 and source 130, giving Vgs near zero. This means that the JFET 100 is on and current will flow into the capacitor 150 and also to any load connected to the source terminal 140. In a typical start-up circuit, the load current is small and most of the current flows into the capacitor 150. The capacitor 150 charges, increasing vdd, which eventually reaches a desired operating value VddOp. At this point, the low-impedance path between gate 170 and source 130 is opened and a second low-impedance path is turned on between gate 170 and ground. These connections have the effect of reverse biasing the gate-source by VddOp volts. If VddOp is greater than the JFET pinch-off voltage, Vp, the JFET 100 will be turned off. If Vp exceeds VddOp, then additional voltage dropping components need to be added in series with the source to increase the magnitude of Vgs, for example diodes or a pnp bipolar transistor.
A JFET without specially designed protection structures will often experience leakage problem or instability at high voltage application. For example, at high voltage charges can spread from high voltage metal leads to low voltage areas along dielectric interfaces. When charges move onto specific regions, such as un-protected gate regions, they may cause surface inversion in certain scenarios. This may turn on a parasitic MOSFET, resulting in leakage. In other scenarios, depending on gate region doping profile, charges may cause instability in channel current.
Accordingly, what is needed in the art is a high-voltage JFET that experiences the benefits of the JFET design without suffering the drawbacks.

Reliable high-voltage junction field effect transistor and method of manufacturing therefor