Abstract:
An improvement is disclosed for use in the process wherein an organophilic clay is manufactured by reacting a smectite-type clay with a higher alkyl-containing quarternary ammonium compound. According to the improvement of the invention, the gelling properties of the resulting organoclay are enhanced, by subjecting the clay as a pumpable slurry, to high-speed fluid shear, prior to the reaction thereof with the ammonium compound.
Abstract:
A self-latching solenoid valve assembly including a valve body having a pressurized air supply inlet port for communicating with a source of pressurized air and at least one cylinder port. A valve member is supported in the valve body so as to be movable between predetermined positions to selectively direct pressurized air from the inlet port to at least one cylinder port. A biasing member is employed to move the valve member in one direction and a solenoid assembly is used to move the valve member in an opposite direction. The solenoid assembly includes a housing with a solenoid coil supported therein and a fixed ferromagnetic pole piece having a passage extending therethrough with a pushpin movably supported in the passage. A ferromagnetic latch is also supported by the housing and spaced from the pole piece. A permanent magnet is disposed between the latch and the pole piece. The magnet is movable toward the pole piece under the influence of an electromagnetic flux generated by a pulse of current generated through the coil in one direction thereby driving the permanent magnet against the pushpin to move the valve member to one predetermined position. In addition, the permanent magnet is also movable away from the pole piece and toward the latch under the influence of an electromagnetic flux generated by a pulse of current flowing through the coil in an opposite direction. When this occurs, the biasing member moves the valve member to another predetermined position. A control circuit for changing the direction of the current through the coil is also disclosed.
Abstract:
Infection of human fibroblast cells with human cytomegalovirus (HCMV) causes down regulation of cell surface expression of MHC class I. The present invention is directed to a mutant with a 9-kb deletion in the S component of the HCMV genome (including open reading frames IRS1-US9 and US11) which failed to down regulate class I heavy chains. By examining the phenotypes of mutants with smaller deletions with this portion of the HCMV genome, a 7-kb region containing at least 9 open reading frames was shown to contain the genes required for reduction in heavy chain expression. Furthermore, it was determined that two subregions (A and B) of the 7-kb region each contained genes which were sufficient to cause heavy chain down regulation. In subregion B, the US11 gene product is involved. It encodes a endoglycosidase H-sensitive glycoprotein which is intracytoplasmic, similar to the adenovirus type 2 E3-19K glycoprotein which inhibits surface expression of class I heavy chains.
Abstract:
The calcium carbonate is prepared by:(a) slaking quicklime in an aqueous medium;(b) carbonating and neutralising the suspension of slaked lime formed in step (a) using a gas comprising carbon dioxide; and(c) separating the precipitated calcium carbonate formed in step (b) from the aqueous medium in which it is suspended. There is added 0.1% to 2% by weight, based on the weight of dry calcium oxide, of a reagent having one or more active hydrogen atoms (or a salt thereof), to the aqueous medium in which the quicklime is slaked in step (a).
Abstract:
A method of preparing precipitated calcium carbonate which comprises slaking quicklime in an aqueous medium, passing the suspension of calcium hydroxide through a sieve having an aperture size in the range of 40 to 70 microns, carbonating the calcium hydroxide and separating the calcium carbonate from the aqueous medium in which it is suspended. The sieved calcium hydroxide is subjected to high energy, high shear agitation which is terminated prior to carbonation. During the carbonation, the suspension of calcium hydroxide is subjected to relatively lower energy and shear agitation compared to the previous high energy, high shear agitation.
Abstract:
A tire display assembly comprising folding blanks which, when assembled, simulates a car seat and is capable of supporting and displaying a vehicle tire. When the assembly is used to display a tire the tire rests on the part of the display which simulates the cushion of a car seat and leans against the part which simulates a backrest of a car seat. A mass support is inserted in the space defined by the parts of the assembly which simulates the cushion of a car seat and is designed to carry the mass of the tire and add rigidity to the tire display assembly. A header upon which printed matter can be posted is situated on top of the part of the assembly which simulates a backrest of a car seat.
Abstract:
There is disclosed a process for preparing a porous inorganic material. The process comprises preparing a cellular aluminosilicate material by foaming or spray drying an aqueous suspension of the material. The cellular material is calcined, leached with hydroxide to remove silica, dewatered and dried to leave a porous, cellular ceramic material.
Abstract:
A particulate porous material suitable for use as a high surface area column packing material comprises particles substantially all of which are not smaller than 5 micrometers and not larger than 1 millimeter in diameter, and each particle is in the form of a substantially cellular body and consists predominantly of an open, three-dimensional matrix of crystals of mullite which define between them interconnecting pores having a width in the range of from 5 nanometers to about 2 micrometers. The particles can be coated with a reactive layer. There is also disclosed a process for producing the particulate porous material wherein a particulate product comprising particles substantially all of which are between 5 micrometers and 1 millimeter in diameter and consisting predominantly of a mixture of mullite crystals and silica is treated with a concentrated aqueous solution of an alkali metal hydroxide at a temperature of at least 50.degree. C.; and the treated particulate product is then washed, dewatered and dried. The particulate porous material may be used as a packing material for a chromatographic or ion exchange column, or for performing biochemical separations, and is particularly useful for immobilizing biological components such as biological macromolecules or biological cells.
Abstract:
An improved process for preparing a polyarylate having a reduced viscosity of from about 0.1 to greater than 1.0 dl/gm comprising the following steps:(a) reacting an acid anhydride derived from an acid containing from 2 to 8 carbon atoms with at least one dihydric phenol to form the corresponding diester; and(b) reacting said diester with at least one aromatic dicarboxylic acid at a temperature sufficient to form the polyarylate, wherein the improvement comprises carrying out said process in the presence of a particular solid adsorbent.
Abstract:
A conductive anti-reflection coating has a surface quarterwave layer that is broken up into smaller portions by inserting one or more thin layers of conductive material in the dielectric material. The resulting stack of alternating layers of a dielectric material and an electrically conductive material provides a solid electrical contact to the buried conductive layer and exhibits a low surface contact resistance.