Abstract: The present invention is directed to the development of compact, coherent sources emitting in the terahertz frequency region using interface phonons. In accordance with a preferred embodiment, a semiconductor heterostructure light emitting device includes a quantum cascade structure having at least an upper lasing level and a lower lasing level. The system uses heterostructure interface phonon bands to depopulate the lower lasing level of at least a three level semiconductor device. The device includes multiple coupled quantum well modules. In alternate preferred embodiments, the device includes quantum dot layers and/or, quantum wire structures, and/or mini-bands in a superlattice, for example, GaAs/AlGaAs superlattice. The phonons in the device improve efficiency, decrease the threshold current and result in system temperatures that are as high as room temperature. The semiconductor device provides emission of terahertz radiation.

Abstract: An electrostatic actuator for adjusting a spacing. A first body has an electrically conducting surface, and a second body has a body surface separated by the spacing from the electrically conducting surface. A conductor layer and an actuator electrode are recessed in the second body, and an electrode face faces the electrically conducting surface across the spacing. The actuator electrode comprises a semi-insulating material with a combination of electrical resistivity and thickness which prevents shorting of the conductor layer to the electrical conducting surface through a dielectric breakdown in the spacing.

Abstract: A disc head slider is provided and includes a disc-facing surface. The disc-facing surface comprises an inside set of surface components that includes an inside cavity dam and an inside sub-ambient pressure cavity having an inside cavity floor. The disc-facing surface further comprises an outside set of surface components that includes an outside cavity dam and an outside sub-ambient pressure cavity having an outside cavity floor. The disc-facing surface also comprises a center set of surface components that is generally disposed between the inside and outside sets of surface components. The center set of surface components includes a center cavity dam and a center sub-ambient pressure cavity having a center cavity floor. The inside, outside and center sets of surface components are separate and disassociated from one another.

Abstract: The present invention comprises a process for cooling a reactor effluent stream from a methanol-to-olefins reactor. The process is efficient and recovers heat from the reactor effluent stream in one or more highly usable forms, preferably high pressure superheated steam.

Abstract: The present invention is a process for quenching a reactor effluent stream. The reactor effluent stream comprises water, olefin product, and methanol and is further entrained with catalyst fines. The process removes water, catalyst fines, and methanol. Particularly, methanol removal from the reactor effluent stream is improved.

Abstract: Herein is disclosed a method and apparatus for reducing particle collection on a slider or gimbal tongue. The gimbal tongue is shaped so as to interact with airflow within a disc drive to direct particles away from the slider and gimbal tongue. The leading edge of the gimbal tongue overhangs the leading edge of the slider. As air current approaches such a geometry, a large pocket of slow moving, high pressure air is created just upwind of the slider. Thus, as particulate matter encounters this pocket, the matter is slowed and its momentum is partially dissipated. A vent is provided in the gimbal tongue. The vent permits an escape route for the particles to move to an area of lower pressure, located on the other side of the gimbal tongue.

Abstract: A device for accessing data stored on a medium includes a substrate that has a transducer on a back side, a bottom side facing the disc, and a surface that protrudes from the bottom side. An insulation layer is placed on top of the surface. An electrostatic actuator electrode is placed on top of the insulation layer. The electrostatic actuator electrode faces the medium across an electrostatically charged portion of an air layer. The electrostatic actuator electrode protrudes above the surface into the electrostatically charged portion of the air layer.

Abstract: The present invention relates to an improved process for obtaining sodium silicate alkali solution depleted of sodium salt and enriched in silica from a mother liquor recovered after isolation of molecular sieves and more particularly, the present invention relates to a process for recycling mother liquor obtained after the isolation of molecular sieves for the preparation of fresh molecular sieves or as a binder for producing Fluid Catalytic Cracking (FCC) catalyst.

Abstract: The present invention is directed to the development of compact, coherent sources emitting in the terahertz frequency region using interface phonons. In accordance with a preferred embodiment, a semiconductor heterostructure light emitting device includes a quantum cascade structure having at least an upper lasing level and a lower lasing level. The system uses heterostructure interface phonon bands to depopulate the lower lasing level of at least a three level semiconductor device. The device includes multiple coupled quantum well modules. In alternate preferred embodiments, the device includes quantum dot layers and/or, quantum wire structures, and/or mini-bands in a superlattice, for example, GaAs/AlGaAs superlattice. The phonons in the device improve efficiency, decrease the threshold current and result in system temperatures that are as high as room temperature. The semiconductor device provides emission of terahertz radiation.

Abstract: A disc drive has an actuator assembly that includes an actuator arm and a suspension having a load beam for supporting a head above a surface of a disc. The actuator assembly includes a plurality of surface features formed on a surface of at least one of the actuator arm and the load beam to reduce aerodynamic drag forces experienced by the actuator assembly. The disc drive may also include an air dam having a finger extending over the surface of the disc, where the finger includes a plurality of surface features to reduce flow separation of an airflow passing over the finger. The surface features may comprise dimples or V-shaped shark skin denticles.

Abstract: A disc head slider is provided and includes a disc-facing surface. The disc-facing surface comprises an inside set of surface components that includes an inside cavity dam and an inside sub-ambient pressure cavity having an inside cavity floor. The disc-facing surface further comprises an outside set of surface components that includes an outside cavity dam and an outside sub-ambient pressure cavity having an outside cavity floor. The disc-facing surface also comprises a center set of surface components that is generally disposed between the inside and outside sets of surface components. The center set of surface components includes a center cavity dam and a center sub-ambient pressure cavity having a center cavity floor. The inside, outside and center sets of surface components are separate and disassociated from one another.

Abstract: Herein is disclosed a method and apparatus for reducing particle collection on a slider or gimbal tongue. The gimbal tongue is shaped so as to interact with airflow within a disc drive to direct particles away from the slider and gimbal tongue. The leading edge of the gimbal tongue overhangs the leading edge of the slider. As air current approaches such a geometry, a large pocket of slow moving, high pressure air is created just upwind of the slider. Thus, as particulate matter encounters this pocket, the matter is slowed and its momentum is partially dissipated. A vent is provided in the gimbal tongue. The vent permits an escape route for the particles to move to an area of lower pressure, located on the other side of the gimbal tongue.

Abstract: This invention relates to a method and system for finite element modeling of enhanced magnetoresistance in thin film semiconductors containing at least one metallic inclusion therein. The method and system utilizes finite element analysis techniques as a function of the applied magnetic field and the geometry of the device for comparing the device characteristics with predetermined qualities and modifying the device to achieve a correlation between the device characteristics and the predetermined qualities.

Abstract: A disc drive has an actuator assembly that includes an actuator arm and a suspension having a load beam for supporting a head above a surface of a disc. The actuator assembly includes a plurality of surface features formed on a surface of at least one of the actuator arm and the load beam to reduce aerodynamic drag forces experienced by the actuator assembly. The disc drive may also include an air dam having a finger extending over the surface of the disc, where the finger includes a plurality of surface features to reduce flow separation of an airflow passing over the finger. The surface features may comprise dimples or V-shaped shark skin denticles.

Abstract: A synthetic faujasite zeolite and a process for preparing the same which includes forming a reaction mixture consisting essentially of water, a source of silica, a source of alumina, Na2O nd nucleation centers, wherein the reaction mixture has molar ratios of constituents including Na2O/SiO2, 0.4-0.9; SiO2/Al2O3, 7-13; and H2O/Na2O, 30-45, and wherein the nucleation centers have molar ratios of constituents including Na2O/SiO2, 0.5-2.0; SiO2/Al203, 10-20; and H2O/Na2O, 10-40; and heating the reaction mixture to a temperature ranging from 90 to 110° C. for a time period ranging from 23 to 29 hours to obtain the synthetic faujasite zeolite, wherein the synthetic faujasite zeolite has a crystallite size ranging from 1500 to 2000 Å, a particle size ranging from 4000 to 8000 Å, and a retention of surface of more than 70% of that of a parent zeolite, when exchanged with ammonia and subjected to hydrothermal treatment at 650° C. for 3 hours and with 100% steam.

Abstract: A chemical compound and composition of Formula 1: ##STR1## wherein Ar represents a phenyl ring substituted by the groups like halo, alkoxy, alkyl or heteroaryl, n=1 or n=2; said compounds and compositions as being useful therapeutic agents for hypertension, ischemic, cardiovascular and other adrenergic receptor related disorders.

Abstract: A process for preparation of fluidized catalytic cracking (FCC) catalyst, comprising silicon stabilized large crystallite sized synthetic faujasite zeolite, aluminum depleted and normal kaolin clay, alumina and silica. The cracking catalyst is highly active and selective for bottom upgradation, it produces less coke and higher gasoline and total cycle oil (TCO) and possesses improved metal tolerance properties when evaluated and compared with a commercial catalyst under conditions of a typical FCC unit in a petroleum refinery.

Abstract: The invention relates to a process for the synthesis of 1-[4-Arylpiperazin-1-yl]-3-[2-oxopyrrolidin/piperidin-1-yl]propanes used as potential therapeutic agents for hypertension, ischemia, cardiovascular and other adrenergic receptors related disorders, having general formula 1 ##STR1## wherein Ar represents a phenyl ring substituted by the groups like halo, alkoxy, alkyl or heteroaryl, n=1 or n=2; a process of preparing said compounds and a method of treating hypertension, ischemia, cardiovascular and other adrenergic receptors related disorders.

Abstract: A process for selective catalytic cracking of a petroleum-based feedstock to produce a product having a high yield of liquified petroleum gas (LPG) and light olefins having 3 to 4 carbons includes providing a fluidized bed reactor which is a high velocity riser, continuously circulating fluidized bed reactor; providing a solid acidic catalyst comprised of: from 1 to 6% by wt. of ultra stable Y-zeolite; from 8-25% by wt. of Pentasil zeolite which is shape selective; from 0-8% by wt. of an active material which is bottom selective; from 0-1% by wt. of rare earth constituents; and from 91 to 60% by wt. of nonacidic constituents and binder; charging the fluidized bed reactor with the solid acidic catalyst and the petroleum-based feedstock; and cracking the petroleum-based feedstock in the presence of the solid acidic catalyst in the fluidized bed reactor. The reactor is operated at a Weight Hourly Space Velocity (WHSV) ranging from 40 to 120 hr.sup.