Abstract: A highly-oriented acrylic staple fiber prepared by simple extrusion of a PAN/H.sub.2 O melt in a gel crystalline state without spinning is provided. The acrylic fibers according to the present invention are characterized by the following properties: a degree of orientation between 80 and 97% observed by an X-ray diffraction; a length distribution ranging from 5 to 500 mm and a thickness distribution ranging from 5 to 500 .mu.m, a length to thickness ratio ranging from 100 to 100,000 determined by a scanning electromicroscope; a tensile strength of 10 to 70 kg/mm.sup.2 ; an initial tensile modulus of 300 to 1,500 kg/mm.sup.2 ; an elongation of 5 to 20%; and a specific surface area of 1 to 50 m.sup.2 /g.

Abstract: A MOSFET having a nonuniform doping channel and a method for fabricating the same.The MOS transistor having a nonuniform doping channel is comprised of: a gate oxide film formed on a semiconductor substrate provided with a trench; a gate electrode of some size formed on the gate oxide film atop the trench and its surroundings, the gate electrode having a portion longer than any other portion and thus, being asymmetrical with regard to the axis passing the center of the trench; a source region formed in a predetermined portion of the semiconductor substrate neighboring a short portion of the gate electrode; a high density channel region formed by doping impurities having the same type with the semiconductor substrate in a predetermined portion of the semiconductor substrate below a longer portion of the gate electrode; and a drain region formed in a predetermined portion of the semiconductor substrate neighboring the high density channel region.

Abstract: Pulp-like short fibers prepared from liquid crystal polyesters capable of forming an anisotropic melt phase at a temperature of 200.degree. C. to 400.degree. C. and having a molecular weight of 2,000 to 100,000 are provided. These fibers consist of microfibrils and have the following highly-oriented fiber characteristics and properties:(a) Tensile strength: 5-30 g/den.;(b) Modulus of elasticity: 200-1,500 g/den.;(c) Orientation angle as determined by an X-ray diffraction: below 20.degree.;(d) Thickness distribution: 0.1-50 .mu.m;(e) Length distribution: 0.1-50 mm; and(f) Specific surface area as determined by a nitrogen adsorption method: 3-30 m.sup.2 /g.

Abstract: A non-spun fiber of acrylic polymers, characterized by a pulp-like short fiber form of a thickness distribution of 0.1 to 100 .mu.m and a length distribution of 0.1 to 100 mm, and by irregular cross-sections in a plane taken perpendicular to the fiber axis and needle point-like ends similar to those of natural wood pulp fibers. The acrylic fiber of the present invention is made of an acrylonitrile homopolymer or copolymer consisting of a least 70% acrylonitrile (by weight) and at most 30% copolymerizable monomers (by weight) and having a viscosity average molecular weight between 10,000 to 600,000. The acrylic fiber according to the invention is further featured by the following physical properties: a degree of orientation of more than 80% based on X-ray diffraction pattern data, a tensile strength of 3 to 10 g/denier and an initial modulus of 30 to 100 g/denier, and absolutely no cylindrically-shaped filament trunks.

Abstract: A new, pulp-like, acrylic short fiber having excellent heat- and chemical-resistance is provided. The fiber has a thickness distribution of 0.1 .mu.m to 50 .mu.m, a length distribution of 1 mm to 20 mm, and a thermal transition temperature (Tg) of above 200.degree. C. The fiber is produced by heating a mixture of polyacrylonitrile and water of about 5% to 100% by weight to temperatures above hydration-melting temperature under seal to an amorphous melt; cooling the resulting amorphous melt to temperatures between the melting and the solidifying temperatures of the melt to form a supercooled melt; extruding the resulting supercooled melt to give extrudates; heat-stabilizing the resulting extrudates at temperatures between 180.degree. C. and 300.degree. C. for 1 minute to 4 hours after drying and drawing; and cutting and beating the resulting heat-stabilized extrudates into an appropriate size.

Abstract: An MOSFET having a nonuniform doping channel and a method for fabricating the same.The MOS transistor having a nonuniform doping channel is comprised of: a gate oxide film formed on a semiconductor substrate provided with a trench; a gate electrode of some size formed on the gate oxide film atop the trench and surroundings, the gate electrode having a portion longer than any other than portion and thus, being asymmetrical with regard to the axis passing the center of the trench; a source region formed in a predetermined portion of the semiconductor substrate neighboring a short portion of the gate electrode; a high density channel region formed by doping impurities having the same type with the semiconductor substrate in a predetermined portion of the semiconductor substrate below a longer portion of the gate electrode; and a drain region formed in a predetermined portion of the semiconductor substrate neighboring the high density channel region.

Abstract: A process for the production of pulp-like short fibers having a highly-oriented fibril structure without spinning is provided. This process comprises heating a mixture of water and an acrylonitrile homopolymer or copolymer to a temperature above the melting temperature of the mixture under enclosed conditions to form an amorphous melt; cooling the resulting amorphous melt to a temperature below the melting temperature to obtain a supercooled melt phase; extruding the resulting supercooled melt phase through a slit die at a temperature between the melting and the solidifying temperatures of the melt phase into an external atmosphere to give extrudates; and subjecting the resulting extrudates to drawing and heat treatment followed by beating mechanically.

Abstract: Novel wholly aromatic polyamides and copolyamides of the formula: ##STR1## are provided. The aromatic polyamides and copolyamides are prepared by condensation polymerizing an aromatic diamine selected from 3,5-diaminobenzophenone and a mixture of 3,5-diaminobenzophenone and m-phenylenediamine with an aromatic dibasic acid chloride in a chemical equivalent amount. The polymers of the invention can be easily dissolved in an organic solvent to give a molding solution suitable for use in the film casting. The film resulted from the polyamides of the invention has excellent physiochemical properties such as durability, chemical resistance, flexibility, compactness, tenacity, transparency and electric insulation.

Abstract: A DRAM cell having a SDTAS structure having a trench stacked capacitor which includes a capacitor charge storage electrode which is in physical contact and is electrically connected to a N+ drain region, and a VCC/2 electrode which is electrically isolated by an ONO layer formed between the capacitor charge storage electrode and the VCC/2 electrode is disclosed. Such cell can increase the capacitance of the capacitor and reduce the area of the cell by reducing the width of the MOSFET, and a method for manufacturing such cell.

Abstract: High molecular weight block copolyamides useful in the production of fibers of high strength and modulus, having the following formula: ##STR1## wherein X is --CH.sub.2 --.sub.m, wherein m is 0 to 12, ##STR2## wherein Z is C(CH.sub.3).sub.2, zero, oxygen or SO.sub.2, are prepared from N,N'-bis(4-aminophenyl) terephthalamide having the formula: ##STR3## which is itself prepared by condensing aniline with dimethyl terephthalate or terephthalic acid, nitrating the product produced thereby and finally hydrogenating the resultant compound.

Abstract: High oriented poly(p-phenylenetetraphthalamide) short fibers having an inherent viscosity of at least 5.0 and a dimension of 2-12 .mu.m in diameter and 1000-5000 .mu.m in length are provided. These fibers have a physical form of irregular cross-sections and needle point-like ends similar to those of natural wood pulp fibers, and crystalline properties such as a crystallinity of more then 50%, an orientation angle of less than 25.degree. and an apparent crystallite size of more that 50 .ANG. as determined from an X-ray diffractogram scan, and a cross-section with four extinction positions through 360.degree. rotation when observed under a polarizing microscope. These fibers are prepared, without spinning steps, by subjecting the molecular chains of poly(p-phenyleneterephthalamide) to mechanical parallelization during the growth of the chains in a polymerization system therefor containing a pyridine/amide-based solvent.

Abstract: The present invention provides a removable attachment for a partial denture having assembly with body member which is to be the connector body therein and a slider member. The assembly is provided with the body member including a slot having a relatively wide and a relatively narrow slot or recess, in which a corresponding portion of slider member can be slid, and a neck portion of slot, which has a major axis which is horizontal and at a right angle to the row of teeth, a slider member including a lock rod and a protruding member suitable for being retained in a notch of the body member and has an aperture which may be engaged by the lock rod.

Abstract: The present invention provides a removable attachment for a partial denture with a sliding locking assembly. The locking assembly is provided with a relatively wide slot and narrower sliding slot or recess which has a major axis which is horizontal and at a right angle to the row of teeth, a locking member including a lock pin and a protruding member suitable for being retained in a recess of the denture and has a hole which may be engaged by the lock pin. The lock member is retained in position by a spring loaded pin and detent to receive the pin. The attachment may be easily operated by a fingertip without injury to the finger and no sudden separation of the partial denture is experienced. It may be used in cases where only the canine teeth of both sides exist as well as in cases where bilateral and/or unilateral teeth are missing. General dental instruments can be adapted for use with this attachment and no special instruments are necessary.