Abstract: The device comprises at least one element for immobilizing certain molecules contained in the medium to be tested. According to the invention, the immobilizing element is in the form of a hydrophilic material fixed on the surface of a plane hydrophobic material, such as for example viscose fibers (2) implanted by flocking into a sheet (3) of polyvinyl chloride. The device (4) further comprises:(a) a bottom plate (5) supporting the plane hydrophobic material,(b) at least one cavity (6) for the liquid medium to be tested, said cavity having an outlet orifice (9) situated above the plane hydrophobic material, and(c) scraping means (8) acting on the hydrophilic material (1) and capable of moving the liquid contained therein over the surface of the plane hydrophobic material (3).

Abstract: Directed to a new molybdenum carboxylic compound and the use thereof as a corrosion inhibitor of steel and other metals particularly in cooling water.

Abstract: Peptides or proteins are sequenced by stepwise degradation while immobilized on a glass support derivatized with a silica-binding substance bearing a free acid group, especially a sulfonic acid group. The support is preferably derivatized with 2-(4-chlorosulfonyl phenyl) ethyl trimethoxysilane.Peptide sequencing performance is improved if the support is also derivatized with a monomeric silica-binding substance bearing a free quaternary ammonium group, such as N-trimethyoxysilyl propyl -N,N,N-trimethyl ammonium chloride.

Abstract: A method of measuring calcium ions is disclosed wherein a calcium sensitive reagent, calcichrome, is immobilized on a porour polymer film. The reaction of the calcium sensitive reagent to the Ca(II) is then measured and concentration determined as a function of the reaction.

Abstract: Constructions are provided for removing interfering red blood cells from a blood sample and providing a measured amount of serum or plasma to a pad. The pad serves as a bridge for the transfer of reagent between two bibulous strips, resulting in transfer of reagent solution through the pad and transport of a material to be measured to the measuring region of the strips. Particularly, glass fiber membranes are used in conjunction with cellulosic membranes to minimize red blood cell lysis, remove red blood cells and provide a measured amount of sample.

Abstract: The present invention relates, a compound for use with selective detectors of the semiconductor resistance type which detect for nitrogenous reducing gases in the atmosphere, especially ammonia and gases containing NH and/or NH.sub.2 groups, said compound comprising the gallium nitride and, oxynitrides of tetrahedral structure according to the general formula: ##EQU1## in which: .quadrature. represents a hole, and 0.ltoreq.x.ltoreq.0.3.

Abstract: An inhibitor composition of sodium hexametaphosphate and a water soluble orthophosphate, together with a pH adjusting, water-soluble alkali, effectively prevents corrosion of metal surfaces by sodium chloride brines. This corrosion inhibitor can be used to prevent corrosion of motor vehicles and steel reinforcing members and structures by brines formed by roadway deicing salt.

Abstract: A method for mechanically working cobalt-containing metals is carried out in the presence of a synthetic metal working liquid containing specific tertiary amines which are alkanol amines capable of reducing both the release of cobalt and the corrosion of iron. The alkanol amine compounds contain one or more hydrophobic groups, such as alkyl groups or higher alkylene oxy groups. A concentrate is provided which contains the alkanol amine compounds and which is suitable, after dilution with water, for use in mechanical working.

Abstract: Method for integrating isotope dilution analysis with chromatography. One embodiment of the invention includes a liquid chromatographic column, a radiochemical detector, an eluent that contains an additive at saturation and a radiochemically labeled derivative of the analyte to be determined. When the analyte, which is not radioactive, is injected, its movement through the column occurs more slowly than the movement of the radioactive derivative situated on the column outside the analyte band. As a result, radioactivity enters the analyte band and isotope dilution occurs. The distribution of radioactivity within the band is used to determine the amount of analyte injected.

Abstract: There is described a container having a closed end and a reagent deposited in the closed end. The container is provided with means for preventing shock from being transmitted to the closed end when that end strikes a hard object.

Abstract: An analytical test strip has a flexible blister (12) thermoformed in a sheet plastics member (22), and a diaphragm (34) which closes the blister to create a reservoir for holding a reagent and/or carrier liquid (32). The sheet plastics member (22) is further formed with one or two spikes (28) the or each of which is disposed within the blister and extends in a reentrant manner towards the diaphragm where it terminates at a point. For use of the dispenser the blister is pinched by finger pressure applied by the user to cause the spike or spikes to puncture the diaphragm and release the reagent and/or carried liquid which then soaks along an absorbent layer (40) until it reaches a viewing window (20). The test substance, particularly a liquid, is applied to the absorbent layer at a cavity (16), and combines with the reagent and/or carrier liquid as it moves to the viewing window.

Abstract: An apparatus for quantitative determination of trihalomethanes comprises a separation unit containing two channels in contact with each other via a microporous membrane that will not react with trihalomethanes, a reaction unit for heating a carrier solution that has passed through the separation unit, a cooling unit for cooling the carrier solution that has undergone complete reaction; and a detection unit for determining the quantity of a fluorescent substance in the carrier solution. A method for quantitative determination of trihalomethanes comprises flowing a sample solution or a mixture thereof with a reducing agent through one of the two channels in the separation unit, flowing the carrier solution through the other channel, heating the carrier solution that has passed through the separation unit and to which an alkaline nicotinamide or a derivative thereof has been added, cooling the carrier solution, and subjecting the cooled solution to fluorimetry.

Abstract: A self-contained assay device is provided, where an analyte may be detected or be quantitated by measuring the distance of a detectable signal from a predetermined site. The device employs two strips separated by a gap, where a flow path is completed by movement of a sample receiving pad into the gap. The movement of the sample receiving pad also results in release of a reagent solution which is then transported through the pad into the quantitation area where the amount of analyte may be determined. Various chemistries may be employed for providing a detectable signal.

Abstract: A new and improved test device and method of determining the presence and concentration of fructosamines in a test sample. The test device includes a test pad comprising a carrier matrix incorporating an indicator reagent composition capable of interacting with fructosamines to produce a detectable or measurable response. The carrier matrix of the device includes a bibulous matrix, such as filter paper, or a nonbibulous matrix, such as a polymeric film. In addition, a new and improved indicator reagent composition comprising a dye, such as tetrazolium violet; a suitable buffer; and an accelerator compound is incorporated into the carrier matrix to provide a test pad demonstrating sufficient color resolution and having sufficient sensitivity to fructosamines in a test sample. Therefore, a fast, more accurate and trustworthy fructosamine assay of a liquid test sample, such as whole blood or serum, is achieved.

Abstract: A dry analytical element for use in detecting a specific component contained in a liquid, which element comprises one or more water permeable layers provided on a water impermeable support, at least one layer of the water-permeable layers containing a composition capable of interacting with said specific component contained in said liquid. The composition contains a leuco dye and a dispersion containing said leuco dye is incorporated in the water-permeable layer, which is formed by dissolving the leuco dye in a hydrophobic solvent containing an aliphatic higher alcohol and dispersing the resulting solution in a hydrophilic medium. The leuco dye has the formula: ##STR1## where R.sup.1 represents an unsubstituted or substituted aryl group, R.sup.2 represents an unsubstituted or substituted alkyl group, and R.sup.3 represents an unsubstituted or substituted aryl group. A process for producing said dry analytical element is also disclosed.

Abstract: The present invention is directed to an agent and method for eliminating ascorbate interference in reagent systems, particularly assay systems using oxidase/peroxidase coupled reactions or similar type redox chemistry. The present invention can also be used in reagent systems involving enzyme/substrate reactions in which the substrate is sensitive to reductants such as ascorbate. The agents of this invention comprise water insoluble cerium (IV) compounds.

Abstract: A test device for colorimetric measurement of chlorine in disinfectant water comprising an iodometric reagent enclosed within a reducing fluid incorporated within a valved enclosure.

Abstract: A novel fluorescent dye, PUR-1, having the structural formula ##STR1## is disclosed that will preferentially stain nucleic acids.

Abstract: A method of predetermining the exact weight ratio of the reactants to produce a product and maintain the weight ratio of the reactants to obtain a maximum yield of the product. The method combines weight ratio measurement with infrared absorbance measurements to determine the maximum yield of an alkenyl succinimide product.

Abstract: The present invention is a method for determination of dicyanodiamide in a plant matrix, i.e. in a plant or a part of a plant. It involves a series of steps including extracting any dicyanodiamide from the plant matrix as well as purifying the dicyanodiamide obtained of interfering substances. Next, the dicyanodiamide obtained is reacted with 3-hydroxy-2-butanone in a non-aqueous, alcoholic hydrochloric acid medium to form 2-guanidino-4,5-dimethyloxazole, and then any 2-guanidino-4,5-dimthyloxazole formed is isolated using liquid-liquid extraction. Finally, any isolated 2-guanidino-4,5-dimethyloxazole is purified by reverse phase high pressure liquid chromatography (HPLC) and the amount of 2-guanidino-4,5-dimethyloxazole is determined spectrophotometrically at a wavelength of 260 nm.