Abstract: The patent relates to a method for spectroscopic and spectrofluorimetric determination of the interaction between materials. The determination takes place using apparatus consisting of several basins.

Abstract: A liquid chemical stripping or cleaning solution is selected by combinatorial high throughput screening. A high throughput screening well array assembly includes (A) a metal substrate and (B) a mask that defines an array of wells on the substrate. A combinatorial high throughput screening system includes (A) a metal substrate and (B) a mask that defines an array of wells on the substrate and a reaction vessel to receive the well array assembly.

Abstract: An apparatus and method for capillary zone electrophoresis includes a polyelectrolyte multilayer positioned in a capillary tube for analytical separations of macromolecules. The capillary comprises a passage defined by passage walls comprising fused silica. The polyelectrolyte multilayer is positioned within the passage adjacent the walls, and comprises an organic polyelectrolyte. The passage may further comprise nonporous silica particles coated with a multilayer including a plurality of polyelectrolyte layers. An apparatus includes a power supply having a positive electrode and a negative electrode for generating an electric field therebetween. The apparatus includes a capillary having a passage formed by passage walls and comprising therein a polyelectrolyte multilayer positioned substantially within the passage.

Abstract: A method of measuring the movement of solid particles and particle interactions in a flowing system includes the step of providing two gamma cameras set up at right angles to each other to periodically record the position of a radioactively tagged particle in the flowing system. Probability distribution functions, particle positions, particle velocities, amongst other useful information, may be determined from the camera data.

Abstract: Formed constituents in an aqueous based fluid biologic material sample are separated from the aqueous constituent of the sample, and are concentrated in an examining instrument's focal plane where they can be examined under magnification. Examples of fluids that can be analyzed in this fashion include urine; cerebrospinal fluid; pleural fluid; ascites; fluids aspirated from cysts such as thyroid and breast cysts; cytologic specimens which have been placed in an aqueous fluid; platelet-rich plasma; and the like. The sample is placed in a chamber having a layer of a hydrophilic hydrogel covering a surface of the chamber. An opposite surface of the chamber is transparent, and may be formed by a microscope slide cover slip, or the like. The volume of hydrogel in the chamber is sufficient so that, when the hydrogel absorbs essentially all of the aqueous fraction of the sample, the hydrogel will expand and fill the chamber.

Abstract: Methods, reagents and reaction mixtures for determining total iron binding capability is disclosed.

Abstract: A microarray storage device includes a cassette having top, bottom and opposite side walls, the front and rear of the cassette being open. The side walls are formed with a multiplicity of parallel rails spaced along the heights of the walls which define compartments in the cassette for supporting a multiplicity of microarrays one above the other. The depth of the cassette is such that the microarrays supported in the compartments project appreciably from the front and/or rear of the cassette. Integral springs are formed in the side walls of the cassette which press down directly on the side edge margins of the microarrays so as to releasably retain the microarrays in their respective compartments.

Abstract: A gas chromatograph has a pressure sensor measuring a pressure in a sample introduction part, a flow control valve controlling carrier gas flow rate, a flow sensor measuring a flow rate of the carrier gas, a split flow path exhausting part of a carrier gas and sample from the introduction part, an exhaust valve placed in the sprit flow path, and a monitor screen. The controller controls the flow control valve to flow the carrier gas at the designated flow rate into the introduction part, reads an output of the pressure sensor after making the exhaust valve fully open, calculates a flow path resistance of the filter by using an output of the pressure sensor and a flow path resistance of the chromatographic column, and controls the monitor screen to display an indication for exchanging the filter when the calculated resistance reaches the preset value corresponding to a state in which the filter is stuffed.

Abstract: A process of using a non-radioactive tracer in the monitoring of the flow of a traced fluid is disclosed. The process includes injecting a tracer containing fluid at a first point and analyzing at least one sample from a second point in the flow of the fluid for the tracer compound. In one embodiment heavy oil is traced with a long chain hydrocarbon having a primary chain of more than 25 carbon atoms, the compound preferably being a saturated hydrocarbon. Exemplary tracer compounds include pentacosane (C25H52); hexacosane (C26H54), heptacosane (C27H56), octacosane(C28H58), nonacosane(C29H60), triacontane(C30H62), hentriacontane(C3lH64), dotriacontane(C32H66), tritriacontane (C33H68), tetratriacontane (C34H70) and the like.

Abstract: The concentration of a hexamethylenetetramine-containing inhibitor in an acid pickling solution that has accumulated dissolved iron from use of the solution in pickling ferriferous material can be estimated with sufficient accuracy for practical control of the pickling process by alkalinizing a sample of the pickling solution to a pH of at least 10.8, so that any iron content of the solution precipitates from the solution, separating the precipitate from the liquid remainder of the alkalinized sample, and determining by colorimetry the concentration in the liquid remainder of formaldehyde produced by acid catalyzed hydrolysis of the hexamethylenetetramine to formaldehyde and ammonia.

Abstract: The present invention is a one-step thermal method for analyzing the acid-base content of earth samples, specifically mine overburden samples. By using a low oxygen concentration, preferably about 3%, the transition metal carbonates in the sample decomposed to produce carbon dioxide at a lower temperature than the alkaline earth metal carbonates. In contrast, alkaline earth metal carbonates decompose at approximately the same (higher) temperature regardless of the oxygen concentration. Any oxidizable sulfur forms present in the sample are also oxidized by using this oxygen concentration so that only one experiment is required to obtain the carbonate and sulfur contents of the sample.

Abstract: A flow cell which can be used in the synthesis of DNA probes on an active surface of the substrate includes a base having a central window opening and a registration surface against which the substrate may be mounted. A gasket having a central opening defining an active area is mounted on the active surface of the substrate and has inlet and output extension openings which extend away from the central opening. A press block is engaged against the gasket to fully enclose an active volume between the press block, the peripheral walls of the central opening in the gasket, and the active surface of the substrate. A press is mounted to the base to selectively press the press block against the gasket and hold it in position. Channels in the press block extend to the extension openings in the gasket to allow flow of reagent into and out of the active volume, which is confined to the thickness of the gasket and can thus be minimized.

Abstract: This invention relates to a reagent and use of that reagent for detecting adulterants in aqueous samples, particularly in biological specimens such as urine samples using a diazo dye precursor such as N,N diethyl-1,4-phenylene diamine and a reagent such as creatinine to stabilize a colored intermediate formed by the reaction of the diamine with nitrite ions for a period sufficient to allow that color to be recorded and compared with a separate peak formed by a halogen-based oxidizing agent which may be present in solution.

Abstract: Formed constituents in an aqueous based fluid biologic material sample are separated from the aqueous constituent of the sample, and are concentrated in an examining instrument's focal plane where they can be examined under magnification. Examples of fluids that can be analyzed in this fashion include urine; cerebrospinal fluid; pleural fluid; ascites; fluids aspirated from cysts such as thyroid and breast cysts; cytologic specimens which have been placed in an aqueous fluid; platelet-rich plasma; and the like. The sample is placed in a chamber having a layer of a hydrophilic hydrogel covering a surface of the chamber. An opposite surface of the chamber is transparent, and may be formed by a microscope slide cover slip, or the like. The volume of hydrogel in the chamber is sufficient so that, when the hydrogel absorbs essentially all of the aqueous fraction of the sample, the hydrogel will expand and fill the chamber.

Abstract: A dynamic sealing structure for pressure vessels used in microwave assisted chemistry is disclosed. The structure includes a cylindrical vessel liner and a removable liner cap, each formed of a microwave transparent material. The liner has a circular mouth with a lip formed of respective first and second beveled edges, with the first beveled edge forming an interior edge of the circular mouth and the second beveled edge forming an exterior edge of the circular mouth. The cap includes respective interior and exterior faces, with a sleeve depending from the interior face and having a circumference that engages the interior surface of the vessel liner for being urged under pressure against the interior surface of the vessel liner. The interior face of the cap comprising a circular channel outward of the sleeve and having a circumference that engages the lip of the vessel liner, and with the channel comprising two beveled edges that respectively engage both beveled edges of the lip of the liner.

Abstract: A filter for reducing the cross-sensitivity of a chlorine dioxide detector to hydrogen sulfide. The filter includes a high surface area substrate impregnated with a silver (I) salt or copper (II) salt which is effective to remove hydrogen sulfide from a gas stream without producing undesirable compounds which might be detected by the sensor. The preferred compounds are copper chloride (CuCl2), copper bromide (CuBr2), silver acetate (AgO2CCH3), silver bromate (AgBrO3), silver bromide (AgBr), silver carbonate (Ag2CO3), silver chloride (AgCl), silver chromate (Ag2CrO4), silver cyanide (AgCN), silver iodate (AgIO3), silver oxide (Ag2O), silver perchlorate (AgClO4), silver permanganate (AgMnO4), silver sulfate (Ag2SO4), silver hexafluorophosphate (AgPF6), silver fluoride (AgF), silver tetrafluoroborate (AgBF4), silver iodide (AgI) and silver trifluoromethane sulfonate (AgO3SCF3).

Abstract: A method for reading out data from microlocations of a microelectronic array involves activating multiple microlocations in parallel and simultaneously detecting the responses from the activated microlocations to determine concentrations of molecular biological material at each microlocation. In a preferred embodiment, the microelectronic array includes electronically addressable electrodes at each microlocation which can be individually activated via a control system. An electrochemiluminescent detection technique is used to detect the presence and determine the concentration of bound molecular biological material that is located at each microlocation. Electrochemiluminescent material is utilized because it gives off light when excited by an applied electrical field. With an addressable microelectronic array, electrical fields can be applied to various combinations of microlocations simultaneously to allow readout of several microlocations in parallel.

Abstract: The invention relates to the study and the manufacture of lubricants used in particular in diesel engines. According to the invention, the neutralization capacity of a lubricant comprising detergent additives is determined by a method which consists in reacting, in a leaktight tank, at a constant temperature, the bases contributed by the additives present in a lubricant film of known mass with a predetermined amount of a liquid acid and in recording, as a function of the time, the values of the pressure within the leaktight tank, and in then determining, from the recorded values of the pressure, at lest one of the following three characterizing parameters: an initiation period for the reaction, a neutralization potential and a reaction rate. The invention finds its application in research and control laboratories of manufacturers of lubricants and in those of engine manufacturers.

Abstract: A method of screening an agent for potential use in the treatment of Alzheimer's disease, comprises reacting, in the presence of the agent, tau protein with a suitable sulphated carbohydrate under appropriate conditions to form filaments, and monitoring for the presence of filaments. Tau protein and sulphated carbohydrate, e.g. sulphated glycosaminoglycan, will react under appropriate conditions to form filaments, either paired helical filaments or straight filaments. If filament formation is affected when the reaction is carried out in the presence of an agent being screened, this is possibly due to an interfering, inhibiting or blocking effect of the agent. An agent which inhibits assembly of PHFs in vitro may also have an inhibiting effect in vivo and thus have potential therapeutic value in delaying the dementing effects of Alzheimer's disease. The invention can thus provide a screen to identify agents worthy of further investigation for use in the treatment of Alzheimer's disease.

Abstract: The invention relates to a sample application device for a gas chromatograph, having an evaporator (1) which can be cooled, can be heated in a temperature-controlled manner, is provided with a carrier-gas feed and has a valve head (11) for holding an exchangeable sampling tube (27), a receiving chamber (4) for the sampling tube (27), a column exit (18) and, if appropriate, a splitter exit (31). In this device, a pyrolyser tube (20), which is coupled to the carrier-gas feed and is held by the valve head (11), is arranged in the receiving chamber (4), in which there is a heating coil (26) into which the sampling tube (27) can be fitted and to which current can be applied by means of a heating conductor (25) which is guided outwards through the valve head (11).