Abstract: According to the invention, cyanide concentrations of approximately 0.001 to 5 mg cyanide/1 are colorimetrically determined in a continuous manner by means of the known cyanidepicric acid color reaction. The solution containing free cyanide and/or cyanide releasable from cyanocomplexes is converted in a system enclosed in a gas-tight manner in the presence of chelate complexing agents, picric acid and alkaline buffer systems in 1-60 minutes at 50.degree.-120.degree. C. to the color complex and the absorbency is measured spectrophotometrically. The method avoids the extraction step which was previously necessary under 0.2 mg CN/1, avoids errors due to HCN gas evolution losses, is easy to manage, not prone to trouble and suitable for the continuous monitoring of waste-water streams or for controlling cyanide detoxification methods.

Abstract: An inhibitor of platelet-related procoagulant activity is included in a collection medium into which a whole blood sample is collected. The inhibitor prevents an initial drop in the recalcified activated clotting time measured during an assay test conducted on the whole blood sample collected in citrate in the medium. The discovery of the problem of the initial drop in the activated clotting time and the solution of including the inhibitor of the procoagulant activity is of considerable importance in heparin therapy, since the initial drop in the activated clotting time of heparinized blood is substantial. The inhibitor can be included with a calcium chelating agent in the collection medium. Prostacylin and imidazole, which is an inhibitor of platelet thromboxane A2 synthesis, are effective inhibitors of this platelet-related procoagulant activity.

Abstract: The measuring probe is equipped with a pellistor and renders possible directly determining in a trouble-free manner volatile constituents which are contained in a liquid medium to be investigated and which can be chemically converted with an accompanying heat effect. Heating devices are provided and, due to the prevention of condensate formation, greatly contribute to obtaining high measuring precision. The response time of the measuring probe can also be significantly reduced by heating a membrane which separates a measuring space containing the pellistor from the liquid medium to be investigated. The measuring probe can be used with advantage for monitoring microbiological processes, for example, in a fermenter.

Abstract: A process of dry dispersal of fine-grained particles on a specimen slide for the purpose of macroscopic or microscopic analysis, and a corresponding instrument for carrying out this process are described. The process permits random, homogeneous distribution of dry particles on a specimen slide in a unilayered, planar distribution, the particles not touching one another at all or only doing so to a negligible extent, i.e. being positioned on the speciment slide without agglomeration. The process steps are: metered input of the fine-grained substance into a sample container; aspiration of the substance by means of a defined partial vacuum, produced in a turbulence chamber, the substance reaching the turbulence chamber via an accelerator tube and then via a distributor tube, and deposition of the accelerated particles on a transparent speciment slide.

Abstract: The present invention provides an aqueous cholesterol standard solution with a definite content of cholesterol, wherein it contains a detergent mixture of 10 to 90% of cholic acid and 90 to 10% of desoxycholic acid or of appropriate salts or derivatives of these acids.The present invention also provides a process for the preparation of this aqueous cholesterol standard solution, wherein a detergent mixture of cholic acid and desoxycholic acid or of appropriate salts and derivatives of these acids is dissolved in distilled water or in 0.9% aqueous sodium chloride solution, an appropriate preservation agent and/or a buffer effective in the pH range of from 7 to 9 optionally added thereto, and a definite, precisely defined amount of cholesterol is dissolved in the solution thus obtained, while stirring and warming to 40.degree. to 60.degree. C.

Abstract: Apparatus and methods for measurement of total organic carbon content of water, particularly of low relative organic content, are described, featuring a single sample cell for exposure of a static sample to ultraviolet radiation and comprising electrodes for measuring the conductivity of the water. The conductivity is monitored as a function of time and the second time derivative of the conductivity signal is monitored to indicate when the oxidation reaction has been completed. Compensation for the contribution to conductivity of the water sample made by the instrument is achieved by subtracting a quantity proportional to the first time derivative of the conductivity at a time when the second time derivative reaches zero, indicating that the oxidation reaction is complete, from the change in the total conductivity measurement, the remainder being equal to the contribution to conductivity made by oxidation of the organic content of the water.

Abstract: An apparatus for diluting a sample with a diluent, comprising a fixed volume measuring chamber, a fixed volume receiving chamber and fluid receiving relationship to the measuring chamber, a gas vent in the receiving chamber, a stop flow junction between the measuring chamber and the receiving chamber, a sample application site in fluid donating relationship to the measuring chamber, wherein the vertical height difference between the sample application site and the stop flow junction is insufficient to provide a hydrostatic pressure capable of overcoming backpressure at the stop flow junction when sample is applied to the sample application site, and the diluent application site and fluid donating relationship to the measuring chamber. Sample and diluent are added sequentially to the apparatus of the invention without requiring any intervening operations. Various means are provided for restarting flow, which causes diluent to wash the sample into the receiving chamber, where the two can be mixed.

Abstract: A process for the continuous production of cyclodextrins employs as a feedstock an aqueous solution of partially hydrolyzed starch with a dextrose equivalent between about 10 and about 15 as the feedstock for an immobilized cyclodextrin glycosyltransferase. In one variant the feedstock is sent to a membrane which removes cyclodextrins and glucose and the retentate is recycled to an immobilized glycosyltransferase so as to effectively utilize the feedstock. In another variant the effluent is passed through a water immiscibled liquid organic compound which forms a solid insoluble complex with cyclodextrins, the solids are continually removed, and the aqueous phase is recycled to an immobilized cyclodextrin glycosyltransferase as in the prior variant.

Abstract: A process for the recuperation, in a form usable by Man, of the proteins present in the sullage of the dairy industry. This process is effected in a number of devices successively including a biological pre-neutralizing tank, in which the alcaline sullage is submitted to acidic fermentation and is freed from sand, a neutralizing reactor for a further acidification of this sullage by depositing natural zoogloea over the divided materials which are within the reactor, a flocculating device for coagulation of the proteins in the sullage in the shape of proteinic flakes under controlled pH conditions, and a floatation device in which the proteins are floated by micro-bubbles and gathered by scraping. A novel combined flocculation and floatation adjuvant is described; it increases the isoelectric pH, so as to decrease consumption of added acid and increase the flocculation pH range.

Abstract: A microwave-based apparatus useful for rapid digestion is provided. The apparatus includes a hollow tubular body having an end sealingly joined to a reaction vessel disposed within a microwave system. The end of the tubular body has grooves for the flow of air through the sealed tubular body/reaction vessel joint. A scrubber removes digestion off gases. Also provided is a rapid, microwave-based, Kjeldahl digestion method.

Abstract: Aqueous chemiluminescent systems have been found to exhibit improved chemiluminescence due to the presence of minor amounts of a water-soluble polymer.

Abstract: Disclosed herein is a composition useful for stabilizing diagnostic reagent which functions to react with a specimen to determine the presence or absence of a biological condition comprising about 0.01 to 35 parts by weight protein or peptide and either (A) about 1 to 90 parts by weight of a saccharide polyol selected from the group consisting of corn syrup and dextrose and optionally up to about 25 parts by weight of a pyrrol, or (B) about 1 to 90 parts by weight of a saccharide polyol and about 0.01 to 25 parts by weight of a pyrrol. Also disclosed is a method of stabilizing such diagnostic reagents comprising using the stabilizing composition, and a diagnositc device comprising a non-absorbent base carrying at least one deposition area in which is carried the evaporative residue of such diagnostic reagent and the stabilizing composition.

Abstract: A thermoelectric heat pump or power source device is provided with P-type and N-type elements made of either thin films or thick films for use on flexible or nonflexible substrates. For flexible units the film type elements are formed on substrates of such flexible, electrically insulation material as, for example, MYLAR and TEFLON; while for inflexible units the elements are formed on substrates of such materials as, for example, Beryllia, Alumina, ceramics, or plastics. Further, the elements are patterned on the different substrates for particular usages. For example, radial element patterns are used for cooling hot spots and ladder element patterns are used for cooling linear hot bodies. Ladder element patterns may also be used on flexible substrates to be folded to form corrugations having cold strips and hot strips on opposing sides to which sheets of suitable material can be attached to form panels, blankets, therapeutic devices or pipe coverings for heating or cooling their contents as desired.

Abstract: A kit of highly uniform microbead standards for flow cytometer alignment, compensation, and calibration, comprising a blank and/or auto-fluorescent microbead population, together with two or more series of calibrated microbead populations which match the fluorescence spectra of labeled samples to be measured on the flow cytometer. Also disclosed is a corresponding method to align, compensate, and calibrate a flow cytometer so as to make measurements on corresponding samples comparable and independent of the specific instrument and instrument settings.

Abstract: A process for the preparation of nitric acid esters of organic hydroxy compounds by reacting an organic hydroxy compound with nitric acid in the presence of both sulphuric acid and in a solvent, followed by separating off the spent acid, substantially neutralizing the residual acidity of the organic solution, and removing solvent to leave the organic nitrate. From 95% to 220% of the stoichiometric requirement of nitric acid for complete nitration is used. The mole ratio of water to sulphuric acid at the end of the reaction is from 0.2:1 to 2.5:1. From 200 to 2000 ml of solvent per mole of hydroxy group is present. Yields of at least 92% are obtained. The invention is particularly suitable for the preparation of alkyl nitrates, alkylene or polyalkylene glycol, monoalkyl ether mononitrates, alkylene or polyalkylene glycol dinitrates, diol nitrates, nitrates containing homocyclic or heterocyclic rings, or nitrates derived from polyols.

Abstract: The present invention is a group of biologically active agents, di-hydroxy alkyl glycerols with vicinal hydroxyl groups and their acetyl-derivatives having the general formula: ##STR1## where R is selected from the group of H and CH.sub.3 CO-- and x+y is between 9 and 21; and methods for their synthesis. The compounds of the present invention are synthesized starting with an unsaturated 1-O-alkyl-glycerol of the formula: ##STR2## where R is an unsaturated alkyl group with a chain length of 12 to 24 carbon atoms and introducing a vicinal hydroxyl into the alkyl carbon chain using either osmium tetroxide or performic acid, produced by mixing formic acid with hydrogen peroxide.The new glycerol ether derivatives exert platelet activating factor (PAF)-like action in vitro in low concentrations, and, surprisingly, in higher doses act as selective antagonists of PAF, or 1-O-alkyl-2-O-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC), activities.

Abstract: A system for breeding fleas comprises a blood reservoir with a feeding membrane and a feeding and reproduction chamber which either has a height dimension of 1.4 to 1.8 mm so as to restrict jumping by the fleas or includes fibrous material so the fleas can walk thereon substantially to a feeding location thereby reducing the amount of jumping required by the fleas to reach the feed location. The method involves providing access by the fleas to a blood food supply for at least 18 continuous hours and influencing the fleas to conserve energy expenditure either by restricting jumping by the fleas or by providing a walking path permitting the fleas to walk substantially to the feed location so as to reduce the amount of jumping required to feed. The feeding period and the system whereby the fleas conserve energy expenditure because they are either restricted from jumping or given an alternative to jumping enables obtaining practical reproduction outputs, i.e.

Abstract: A biomedical implantable shunt is provided having an enlarged generally circular pump body and a perforated distal and proximal catheter attached to said body. The catheters are intended to have excess length so they can be cut to proper length as necessary to fit a specific patient. The pump body includes a vestibule at the outlet end directly connected to the distal catheter. A pair of one-way miter valves are provided within the pump body. The inlet valve is directly connected to the entrance provided for the proximal catheter while the outlet valve is positioned within the vestibule which is connected to the distal catheter. A longitudinal ridge is provided in the base member of the pump body with one end of the ridge positioned directly under the inlet valve to eliminate the possibility of the valve becoming sealed in the closed position during the pumping operation.

Abstract: A method of analysis by high performance liquid chromatography is provided for obtaining an analysis of three components, namely acyclic paraffins, cycloparaffins and unsaturates, present in a liquid hydrocarbon mixture. The method comprises introducing a sample of the mixture to be analyzed into an unsaturates-selective column, passing the eluents from the unsaturates-selective column to a second column, eluting the separated components from the second column, detecting the presence of paraffins and naphthenes in the effluent from the second column, eluting the separated components from the unsaturates-selective column, and detecting the presence of unsaturates in the effluent from the unsaturates-selective column. The unsaturates-selective column is a silver-modified ion exchange column. The second column is a slurry packed column packed with a microparticulate material. The detector is a dielectric constant detector.

Abstract: An excrement examination unit includes a handle member having an elongate stirrer inserted in a housing. Fecal sample is picked up by the stirrer and dissolved into a medical saline solution by shaking the stirrer. Fecal solution is downwardly discharged and absorbed on a liquid-penetrable filter so that a simple occult blood test can be conducted by poking a test paper onto the filter through a slot formed in the housing to prevent a fecal contamination. Fecal solution is next downwardly discharged into a test tube for further laboratory examination.