Abstract: A cellulosic ultrafiltration membrane is provided having a microporous base resistant substrate and an ultrafiltration layer form of a cellulose ester or cellulose.

Abstract: A product having a porous polymeric structure is formed from a non-porous polymeric sheet by sequential contact of the non-porous sheet with a solvent for the sheet and then a non-solvent for the sheet. The porous product can be porous through all or a portion of its thickness.

Abstract: A high-porosity metallic membrane element comprising a sintered element having at least about 55% porosity, the sintered element comprising a matrix of substantially interconnected pores, each of the pores being defined by a plurality of dendtritic metallic particles. A preferred form is made from pure nickel, preferably filamentous nickel powder. The high-porosity metallic membrane element, comprising the aforementioned sintered element having at least about 55% porosity, can be sealed within a filter housing to produce a highly porous filter device with a filtered fluid flow path through the metal membrane element. Also disclosed is a method of making the high-porosity metallic membrane element which includes depositing by air-laying techniques a substantially uniform low-density bed of a sinterable dendritic material into a mold suitable for applying compressive force thereto, compressing the low-density bed of sinterable dendritic material to form a green form, and sintering the green form.

Abstract: A device is provided comprising a piezoelectric material and at least one non-crystalline non-crystalline metal oxide, crystalline-non-zeolite metal oxide and mixtures thereof coating chemically reactive with trace quantities of water in chemically reactive and inert gases. The piezoelectric material is bonded to a conductor for delivering an alternating electric current and to a conductor for transmitting resonant vibration frequency of the crystal. The reactive metal oxide coating has an effective thickness which provides a serviceable life for the coating while not being so thick as to prevent vibration of the piezoelectric material.

Abstract: A new method and apparatus is described for conducting an integrity test on porous membranes and membrane filters and for conducting a pore-size characterization of membrane. The method and apparatus apply to membrane integrity tests and pore-size characterizations which are based on the dependence on the pore size of the pressure required to intrude a non-wetting, electrically conductive liquid into and through the pores. Electrical-measurement methods are described for identifying the pressure at which intrusion occurs.

Abstract: A sanitary slider valve shown specifically as a rotary carousel diaphragm valve which has a thermoplastic elastomeric diaphragm integrally molded to form the multiple sealing ports of the rotor/stator interface is described. Ports or grooves molded into the face of the elastomeric diaphragm are positioned to sealably engage grooves or ports in the stator face, and to form sanitary elastomeric tubular ducts leading through the body of the rotor or of the stator, terminating as elastomeric flanges. These flanges permit direct connection to sanitary flared piping flanges within the carousel which lead to and from multiple columns or other solid phase bed segments, or to sanitary flared piping flanges connecting the stator to piping interconnecting the multiple carousel columns to each other and to external supply and collection lines.

Abstract: A process is provided for rapidly and non-destructively evaluating the solute retention characteristics of porous membranes using a novel liquid-porosimetric technique. A ratio of two membrane permeabilities is measured at preselected operating conditions using a pair of mutually immiscible fluids, one of which is employed as a membrane wetting agent and the other used as an intrusion fluid. At the first operating condition, a particular transmembrane pressure is chosen so as to intrude nearly all of the pores present in the membrane sample. At the second operating condition, a particular membrane permeability is chosen so as to achieve a specified permeability ratio. The resulting transmembrane pressure corresponding to this particular membrane permeability is compared to a previously established standard curve which permits identifying the solute retention characteristics of the porous membrane.

Abstract: A membrane cutter and retriever is disclosed which includes a hollow circular die securely fastened through a hollow connector to the luer opening of a syringe. The die/syringe assembly is inserted within a filter holder unit having a membrane secured to the bottom thereof. The die contacts the periphery of the membrane and is rotated to cut and release the membrane from the holder unit. The plunger of the syringe is then raised to create a vacuum which forces the cut membrane into the hollow die where it is retained until such time as the plunger is lowered to create sufficient pressure to deposit the membrane at a desired location for subsequent analysis.

Abstract: A getter-filter composite membrane element, comprising a sinterable getter material and a sinterable metal filter material, the composite element defining a matrix of substantially interconnected pores. Membrane elements may be comprised of at least three alternating layers of a first sinterable getter material layer and a second sinterable metal filter material layer, the first getter layer being located between the second filter layers, the second layers acting to hold the getter layer, and to retain the getter particles. Also disclosed is a method of making the getter-filter element.

Abstract: The packaging is in the form of a tape comprising first and second films (4,6) between which are sandwiched objects (7) each placed in an envelope formed by a seal (8) between the films. The first method and the device (20) enable the envelopes to be opened and the objects (27) to be taken therefrom easily. The microbiological analysis method uses a tape with alternating filter membranes for the liquid to be analyzed and absorbent pads for a nutrient medium.

Abstract: A membrane support apparatus is provided which includes a top section, a mating base section and a membrane support surface within the mated sections. The apparatus includes a first peripheral seal formed by extension on one of the sections which mates with a groove on the other of the sections, a second seal formed by a smooth surface on either the groove or the extension which mates with a bead on the other of the groove or extension to form a second peripheral seal. The top section and the base section optionally can form a third peripheral seal about the periphery of a membrane on the membrane support surface.

Abstract: Porous polymeric structures are provided along with a method to make such structures comprising heat-induced phase separation of a polymeric solution exhibiting a lower critical solution temperature.

Abstract: A self-priming filter holder for filtration of intravenous liquids is provided and is formed of one or two housing portions sealed to a core portion. The core portion has one or two ribbed surfaces forming a plurality of flow paths sealed at one end and open at a second end and at least one channel preferably larger than the flow paths. The channel(s) is in fluid communication with the flow paths and an outlet. An inlet is provided to the interior of the housing portion(s) which are sealed from the ribbed surfaces by hydrophilic membranes. The housing portion(s) can be provided with gas vents sealed with hydrophobic membranes. Fluids pass through the flow paths in one direction and through the channel(s) in an opposite direction to remove gas from the flow paths and channels prior to use.

Abstract: A system for forming a time modulated electrospray from a sample solution is provided. Further systems for analyzing this time modulated electrospray also are provided. An element connected to a time modulated voltage source is positioned substantially opposite an electrospray apparatus and an analytical apparatus so that the initial direction of travel of the electrospray is reversed and the electrospray is diverted into the analytical apparatus. A second time modulated voltage can be provided which causes the periodic deflection of an ion beam, resulting from a time modulated electrospray, into a mass analyzer in a vacuum system. The modulation of this second voltage source is coordinated with the time modulation of the first voltage source which causes the formation of an electrospray in such a manner that efficiency of sample introduction into the mass analyzer is improved.

Abstract: A method for the preparation of an open cell porous metallic material is provided. The method includes first molding a metal oxide powder into a desired gas-permeable body, then firing the body to obtain a sintered body of metal oxide. Lastly, oxygen is removed from the sintered metal oxide by firing in a reducing atmosphere. In a preferred embodiment, metal oxides such as NiO are combined with polyvinyl alcohol (PVA) and compressed into a molded body which is then air-fired and reduced. Pore sizes of less than 1 .mu.m are characteristic. Porosity of up to 64 percent has been demonstrated for nickel. In another preferred embodiment, mixed systems of metal alloys are demonstrated. In particular, results are shown for a NiO--MoO.sub.3 system.

Abstract: The present invention describes a cartridge of hollow fibers intended principally for the refermentation in the bottle of sugar-containing wine according to the traditional so-called "champagne" method. The cartridge has a perforated tubular body in which are arranged microporous hollow fibers preferably hydrophilic and a few hydrophobic and which are folded in a U shape and which are filled with yeasts. The cartridge is of a size to be inserted in the neck of a bottle and allows refermentation to occur by ensuring the maintenance of an optimum exchange surface between the wine and the yeasts.

Abstract: An improved apparatus and method for the analysis of ions generated by matrix-assisted laser desorption is disclosed. This apparatus and method enhances the mass spectral resolution compared to previous devices and methods by producing electrical modulation of the kinetic energy imparted to the generated ions in a matrix-assisted laser desorption mass spectrometer. This modulation causes parent ions of interest to be substantially reflected (and detected) or substantially not reflected (and not detected) within the spectrometer, while fragment ions produced from the parent ion of interest are substantially reflected (and detected) independent of said modulation. A difference signal is generated between electrical signals sensed when the parent ions are reflected and electrical signals sensed when the parent ions are not reflected thereby mitigating the effects on the mass spectrum of the undesired fragment ions.

Abstract: Novel carbamate compounds, novel silylcarbamate compounds and novel reversed phase materials comprising a silica substrate modified with a modified novel silylcarbamate compound are disclosed which may, for example, be used as stationary phases for liquid chromatography applications. Attached to the carbamate group are several reversed or normal phase producing groups such as cyanoalkyl, tertiary butyl, dibutyl, octyl, dodecyl, tetradecyl, octadecyl or benzyl. The new stationary phases may be endcapped with a short chain alkyl silane. One particular advantage of these stationary phases is decreased interaction with basic samples due to shielding of the unreacted silanol groups on the silica surface. The new phases are particularly useful in the chromatographic analysis of basic samples or more generally for samples having an undesirable interaction with the unmodified silanols.

Abstract: An improved method for determining a viable microbial cell count in a sample wherein the method comprises the steps of filtering a microbe-containing sample solution through a hydrophilic membrane, thereby trapping viable microbes thereon, then spraying an extracting reagent onto the viable microbes trapped on the membrane, thereby lysing the microbial cells. The lysed cells are then sprayed with a solution of luciferin-luciferase reagent, thereby inducing a luminesent signal. The signal is then quantified using a CCD-based device. The improvement comprises the use of a volatile alcohol extracting reagent for lysing the viable microbes, then evaporating the alcohol prior to spraying the luciferin-luciferase solution, leaving a concentrated ATP,containing solution for enhanced luminescent detection.

Abstract: A filtration system is disclosed which operates with a single supply pump to achieve backwashing in an expeditious manner. The system includes a fluid supply source for a feed fluid to be filtered, a feed pump in fluid communication with the source and a membrane filter module for separating the fluid into filtrate and retentate streams. A collection reservoir is also provided which has at least two isolated fluid compartments movably separated from one another, one compartment for accumulating filtrate, the other being in fluid communication with the supply pump. In a preferred embodiment the collection reservoir is in the form of a diaphragm unit. At appropriate times, valves are activated to divert the flow of feed material from the supply source to the other chamber of the diaphragm unit.