Abstract: The determination of the halogen content in a substance is carried out by oxidative combustion of the sample under a continuous flow of gas, in the presence of oxygen, the gases coming out of the combustion reactor being then carried by gas flow to analysis equipment.

Abstract: A method for measuring or detecting halogenated organic compound content. For example, the method can be used to identify polychlorinated biphenyls ("PCB's"), contaminating soil or oil. The method is based on a light induced color producing reaction between a photodonor reagent and a halogenated organic compound. This reaction produces change in the optical absorption of the light exposed photodonor. Reversing the role of reagent and halogenated organic compound provides a method for identifying polyaromatic organic compounds such as pyrenes.

Abstract: An automated analysis system is provided for the determination of impurities in a liquified hydrocarbon stream. The system employs a hydrocarbon capture vessel for capturing a hydrocarbon sample, a water scrubbing vessel for extracting impurities from the hydrocarbon sample and a titration zone for analyzing the amount of impurities in the aqueous extract.

Abstract: A sensor device includes ultra-large pore crystalline material M41S as a selective detecting element, and a measuring element for quantifying physical, chemical or biological events which occur within the crystalline material. The crystalline material may also contain an additional selective detecting component within its pores.

Abstract: A sensing chemistry for halogenated hydrocarbons includes pyridine or a pyridine derivative and a strong organic alkoxide base. The sensing chemistry may be in a nonaqueous organic solvent or in a solid state matrix. The base reacts with the halohydrocarbon to produce a carbene intermediate reaction product, which in the absence of water preferentially reacts with the pyridine to form a colored and/or fluorescent product.

Abstract: A process for the continuous quantitative determination of the concentration of fluorine-containing compounds in gases by treating a gas that contains a fluorine-containing compound with an aqueous solution of an amine and determining the concentration of the eliminated fluoride ions by a direct potentiometric method.

Abstract: Methods are disclosed for conducting assays. One such method comprises providing in combination a first bibulous member zone ("first zone") and a liquid medium containing a component. The first zone has non-diffusively bound thereto a reagent interreactive with the component. Conditions are selected wherein the liquid medium and at least a portion of the component contained therein traverse all of the first zone and migrate by capillary migration into a second bibulous member zone ("second zone"). The second zone is of a different composition than the first zone and is incapable of specifically binding the component except when an analyte is to be detected and the method further includes causing a reagent to become bound to the first bibulous member zone in relation to the amount of analyte present.

Abstract: A method for monitoring automatically, on-line chloride content in a fluid stream in an oil refinery. Additionally, the present invention provides a method for neutralizing the acids resulting from the chloride in a fluid stream. Pursuant to the method, a fluid sample is collected. To the sample is added a sulfide scavenger that will react with the sulfide that is present to create a reaction product. The fluid is then passed to a reaction or measurement cell including a chloride specific electrode. Prior to contacting the chloride specific electrode, the fluid must pass through a membrane that prevents the reaction product from flowing therethrough. The fluid that flows through the membrane is allowed to contact the chloride specific electrode. This allows the chloride content to be monitored in the fluid. The concentration of chloride can then be used to generate a signal to control the addition of a neutralizing agent to the fluid stream.

Abstract: A gas sensor has a gas-sensing component which changes color and/or conductivity on exposure to certain gases, which component comprises a (mono, di or tri) azatetrabenzoporphyrin. Certain (mono, di or tri) azatetrabenzoporphyrins containing a transition metal ion selected from chromium (III), vanadyl, manganese, cobalt or iron (III) are novel.

Abstract: In a color reaction method for detecting particular classes of explosives, a sample from a suspect source is subjected serially to the indicated reagents in the liquid phase, the reagents after the first being applied only if no color reaction has been obtained in the preceding test. The second and third reagents only are applied in presence of the preceding reagent(s). The first reagent is an alkaline solution of a diazotizable aminoaromatic azo-dye precursor, which detects nitroaromatic explosives. The second reagent is a strongly acidic reagent containing a nitrate to nitrite ion reducing agent and a diazo-coupler, which detects organic nitrates and nitramines. The third reagent is zinc powder suspended in a liquid, which detects inorganic nitrates. The fourth reagent is an aniline salt in a homogeneous strongly acidic solution including a water-miscible organic solvent, which detects chlorates and bromates. The invention includes also a test kit for use in the method.

Abstract: An improved ion mobility spectrometer (IMS) and method for operating the same which enables analysis of chlorine dioxide in a mixture of gases which also includes the interferant chlorine. A controlled concentration of an amine such as methylamine is added to the air carrier gas stream prior to application of the carrier gas stream. The amine suppresses the chlorine peak, thereby improving the specificity of the IMS to chlorine dioxide. The IMS of the present invention also includes an improved membrane filter for pre-filtering chlorine, and a software algorithm for accommodating peak drift.

Abstract: The concentration of an organic chlorine compound contained in a gaseous medium is measured in situ by feeding the gaseous medium to a reaction zone and oxidizing the chlorine compound to produce a reactive gas capable of reacting with a chemiluminescent compound to cause chemiluminescence. The reactive gas is contacted with the chemiluminescent compound contained in a cell to cause chemiluminescence whose intensity is proportional to the amount of the reactive gas produced by the oxidation of the organic compound. The concentration of an organic chlorine compound contained in an aqueous medium may also be measured by the similar method after separating the organic chlorine compound as vapors from the aqueous medium. A device suitable for the above measurement is also disclosed.

Abstract: Antibodies are raised against immunogens which include an aromatic ring moiety, preferably the compound 6-aminohexyl-p-tolylacetamide, which immunologically cross-react with small aliphatic organic compounds. These antibodies are useful in immunoassay methods for detecting a class of very small organic molecules such as 1,1-dihaloethylene and 1,1,2-trihaloethylene, whether alone or as a functional group on another molecule. Such antibodies and methods provide important tools for detecting significant environmental pollutants.

Abstract: An automated analysis system for the determination of impurities in a liquified hydrocarbon stream. The system employs a hydrocarbon capture vessel for capturing a hydrocarbon sample, a water scrubbing vessel for extracting impurities from the hydrocarbon sample and a titration zone for analyzing the amount of impurities in the aqueous extract.

Abstract: Apparatus and method for qualitatively and quantitatively analyzing infrared emission from excited molecules in samples of interest is disclosed. Over the wavelength interval from 1 to 5 um, two strong emission bands are observed with a PbSe detector when organic compounds are introduced into an hydrogen/air flame. The band at 4.3 um (2326 cm.sup.-1 is due to the asymmetric stretch of carbon dioxide while the band at 2.7 um is due to both water and carbon dioxide emission. The carbon dioxide emission at 4.3 um is most intense at the tip of the flame, and increases with the amount of organic compound introduced into the flame. For chromatographic application, an optical filter can be used to isolate the 4.3 um emission band. The infrared emission detection system finds application in the determination of total inorganic carbon, chloride and available chlorine in aqueous samples.

Abstract: NO.sub.2 and other electron acceptor gases can be detected at 5 volume parts per million by tetrathiafulvalene TTF. The TTF may be incorporated in a polystyrene film, which changes its infra-red spectrum and conductivity upon exposure to such gases.

Abstract: A method for evaluating surface micro roughness of a silicon substrate includes the steps of soaking the silicon substrate in a mixture of hydrochloric acid of 30 to 40 vol %, hydrogen peroxide solution of 30 to 40 vol % and deionized water whose volume ratio is approximately 1:1:16.7, and measuring an amount of chlorine element incorporated into native oxide film on the silicon surface through the soaking process to evaluate the degree of the micro roughness on the silicon substrate surface.

Abstract: A test device and method of use for determination of aqueous halide ions is described. The device has a porous matrix containing a silver dichromate reagent that gives a colorimetric response in the presence of halide ions and a cationic substance that prevents the formation of silver oxide products. The cationic substance has no colorimetric response in the presence of halide ions that would interfere with the measurement of the colorimetric change of the silver dichromate reagent.

Abstract: Bromide ion content in a photographic developer is an important variable to be controlled by photoprocessors who process color reversal material or color negative film. The bromide content of such developers can be determined by titration with silver ion, using tetraiodophenolsulfonephthalein (TIPS) or other suitable adsorption indicator, after the developer has been acidified with an organic acid such as citric acid. This titrimetric method can be adapted for use in a test kit which is designed for use by photoprocessors who otherwise lack the chemical sophistication to readily conduct analysis by titration, or who have the necessary sophistication, but wish to gain the benefits and convenience available from use of a test kit specifically designed for conducting the analytical method.

Abstract: Detecting the presence of PAC's in the effluent of a combustions system by detecting the presence of a high molecular weight PAC's having five or more rings. A position along the effluent stream is selected at which high molecular weight PAC's may be present. The effluent is illuminated with radiation having a wavelength absorbed by the high molecular weight PAC's in the gas phase. The fluorescence from the illuminated effluent is detected, and analyzed by comparison to the known fluorescence of high molecular weight PAC's in the gas phase to determine the presence of the PAC's in the effluent. The effluent composition may be controlled in response to the detection.

Abstract: Para-substituted phenylene ring compounds where the substituent moieties are selected from the group consisting of aminoalkyl rings and alkyl rings, such as 1,1'-para-phenylene dipiperidine and 1,1'-para-phenylene dipyrolidine, can be used as colorimetric reagents for detecting the presence of small quantities of chlorine or ozone in water.

Abstract: Chlorine and hydrogen sulfide contamination in a local atmosphere is removed by drafting a ventilation flow stream of the contaminated atmosphere over an activated carbon adsorber bed. Saturation of the adsorber bed by adsorbed contaminant occurs as a progressive front advancing along the flow stream direction. One or more chlorine and hydrogen sulfide sensitive monitors signal passage of the saturation front at designated bed depth points. Each monitor is exposed to a small air sample flow from the bed at the respectively designated point. Each sample flow is directed serially over two reactive paper filters: the first being impregnated with 0-toluidine to remove Cl.sub.2 and the second being in impregnated with lead acetate to remove H.sub.2 S. Both filters respond to the respective compounds with a color change. Monitor construction and assembly places both filters side-by-side behind transparent chamber windows for manual observation of the color change without disassembly of the monitor unit.

Abstract: Single or multi-cell reservoir sensors with single illumination sources and one or more detectors per cell unit have an arrangement whereby a gaseous, vapor or liquid sample enters the cell body and interacts with a sensing solution to detect and quantify a given species. Entrance of the sample into the sensor is through an opening in the cell body which may be covered with a membrane to contain the sensing reagent and to presort the species entering the cell. Reservoir cells can be used with organic, inorganic or biochemical sensing materials. A variety of sensors as alcohol, drugs of abuse, organic halides, cyanide and inorganic ions are provided.

Abstract: For the simultaneous measurement of two parameters of a liquid or gaseous sample, in a fluorescence measuring device in which the influence of the aging processes of the indicator substance and the fluctuations in the light intensity of the excitation light source are to be avoided, it is proposed that the change in the first parameter to be measured is obtained from the change in the ratio of two intensity values, determined for different wavelengths of the excitation and emission spectrum of the indicator substance, and the change of a second parameter is obtained from the change in the decay time t of the fluorescence radiation of the same indicator substance from the group of aromatic hydrocarbons, the aromatic heterocycles and the metal organic complexes.

Abstract: The molar concentration of chloroformate in an organic chloroformate solution is determined by adding an excess of a monohydroxyaromatic compound, water and a catalytic amount of a 4-dialkylaminopyridine such as 4-dimethylaminopyridine, titrating with aqueous base and taking as the end point the volume of base which achieves complete conversation of chloroformate groups to monoaromatic carbonate groups, as shown by a rapid rise in the pH of the aqueous phase of more than two points to a value in the range of 7-9. This method is particularly applicable to the determination of bischloroformate molar concentration in systems to be converted to cyclic polycarbonate oligomers. Conversion may be effected by condensation in the presence of a trialkylamine and aqueous base in the amount of about 3 moles per mole of bischloroformate.

Abstract: Air containing water-soluble oxidizing agents, usually predominantly hydrogen peroxide, is exposed in concurrent flow to water that may be acidified if the air contains interfering acidic reducing agents such as sulfur dioxide. After that exposure the gas is separated from the liquid and, if the stripping liquid has been acidified, it is then neutralized. The neutral stripping liquid containing the oxidizing agents is mixed and then reacted with an iodide solution in the presence of a catalyst, after which the reaction products are passed, as the cathode solution, through an electrochemical concentration cell which has an anode chamber filled with a concentrated iodide solution as an anode solution.

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: For the analysis of a sample in a method capable of wide application, the sample is reacted in a combustion reaction with elementary pure fluorine in a multiple molar excess in relation to the sample in a reactor of pure nickel so that the products of fluorination may be analyzed by spectrometry. A line spectrum can be produced in this manner, for example, from a silicon carbide sample combusted or reacted with elementary fluorine.

Abstract: A method capable of detecting low concentrations of a pollutant or other component in air or other gas, utilizing a combination of a heating filament having a catalytic surface of a noble metal for exposure to the gas and producing a derivative chemical product from the component, and an electrochemical sensor responsive to the derivative chemical product for providing a signal indicative of the product. At concentrations in the order of about 1-100 ppm of tetrachloroethylene, neither the heating filament nor the electrochemical sensor is individually capable of sensing the pollutant. In the combination, the heating filament converts the benzyl chloride to one or more derivative chemical products which may be detected by the electrochemical sensor.

Abstract: Gas samples withdrawn from within a reactor vessel (or process in general), as well as from one feed gas thereto, are passed to gas analyzers for particular components or impurities desired to be measured. The response time of the reactor analysis system employed is advantageously minimized by the elimination of dead gas space within the system and the provisions for rapid purging of the system or of individual gas analyzer feed lines. The flexibility of the system to measure both particular gas sample components and periodically present impurities using the same analytical instruments is generated by the addition of an in-line reaction system comprised of reactant addition means and/or catalyst means to individual sample lines leading to particular analytical instruments.

Abstract: A flow injection analysis flow cell suitable for precipitation titration flow injection analysis wherein the flow cell has a chamber and a dammed space within the chamber. The carrier containing the precipitate is flowed into the dammed space and overflows it into the chamber. The flow cell is designed so that a chemical sensing probe can be inserted into the dammed space to allow precipitation titration flow injection analysis with reduced problems of flow cell plugging.

Abstract: A method for measuring the halogenated organic compound content, e.g., polychlorinated biphenyl ("PCB") content, of soil samples may effectively be carried out with an inexpensive, disposable (that is, single-use) field test kit. The method includes contacting a weighted soil sample suspected of containing PCB or some other organohalogen contaminant with a pre-mixture of water and an organic solvent in which water is slightly soluble. The water extracts any inorganic halides which may be present and would adversely affect the accuracy of the test. The organic solvent wets the moist soil sample sufficiently to extract any PCB therein. The resultant organic solvent phase is separated from the soil sample and aqueous phase, dried by passage through a moisture-adsorbent material to remove or at least greatly reduce its moisture content, and analyzed by means of a color-change titration to determine halide content, and thereby the PCB (or other organohalogen) content, of the soil sample.

Abstract: The concentration of molecular fluorine in a mixed gas such as an excimer laser gas can be determined easily, quickly and accurately by passing the mixed gas through a column packed with an alakli metal or alkaline earth metal compound which has no halogen atom and reacts with fluorine to form a solid fluoride together with molecular oxygen and/or carbon dioxide and measuring the concentration of oxygen or carbon dioxide in the fluorine-free gas flowed out of the packed column. If the mixed gas initially contains molecular oxygen or carbon dioxide, its concentration is measured separately after fixing fluorine in another column packed with an element which forms a fluoride. This analyzing method can be used in a feedback control system for controlling the concentration of fluorine in an excimer laser gas during operation of the laser to thereby stabilize the laser output power.

Abstract: A gravimetric method for determining the iodine adsorption number of carbon black is disclosed. The concentration of an accurately weighed iodine solution is determined by titrating with a standardized titrant and determining the concentration of the iodine solution by the weight of the standardized titrant needed to reach the titration endpoint. An appropriate amount of accurately weighed iodine solution is mixed with an accurately weighed amount of carbon black, and the mixture is equilibrated. The concentration of the resulting supernatant is determined by determining the weight of the standardized titrant needed to reach the titration endpoint. The iodine adsorption number is then determined based on the gravimetrically determined concentrations of the solutions. Preferably, the method is semi-or fully automated, and an apparatus for accomplishing the same is disclosed.

Abstract: A heat treatment device for the conversion of gaseous test samples into constituents determinable by a detector provides the possibility of obtaining the desired pyrolysis products even during the sampling, then feeding them directly to the detector. The device has a small structural shape, and is able to be carried and used easily and operated independently of an external energy supply. The heat treatment device is connectable to a number of different detectors. A container 1 through which the test gas can flow is provided with a chemical filler 5, 7, 8 capable of an exothermic reaction, and with a starter 4 initiating the reaction.

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: The present invention provides a general assay methodology suitable for the detection of organic analytes which are neither aldehydes nor ketones and for inorganic substances. The methodology utilizes prepared sensitized films of derivatizing agents and specific developer solutions for the selective and controlled formation of light scattering crystals whose presence serves as a qualitative and/or quantitative measure of the individual analyte of interest in the sample.

Abstract: A method is provided for detecting the presence of organic materials in an aqueous sample. The materials are decomposed by simultaneous exposure to ultraviolet radiation and acoustic energy to decompose the materials to simple decomposition products. The simple decomposition products such as ammonium ion, halogen ion, alkyl ammonium ions, or sulfate ions, are then detected by conventional analytical devices and methods.

Abstract: Procedure and apparatus for the continuous analysis of the chloride ion content of overhead waters downstream of a hydrocarbon distillation column for more effectively preventing hydrochloric acid corrosion of downstream equipment while avoiding over-neutralizing the overhead waters to the detriment of the hydrocarbon product. This procedure comprises the following operations, in the order given or in a different order:Drawing from the overhead waters a stream of water for analysis;removing from the sample so drawn the hydrocarbons as well as the suspended matter;blowing nitrogen into the sample to sweep away the hydrogen sulfide ans the residual hydrocarbons;oxidizing the S.sup.2- or HS.sup.- sulfide ions to sulfate ions;acidifying the sample;finally, measuring by ionometry, and more particularly by means of a combined electrode, the content of chloride ions present.

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: The invention is directed to a gas measuring device having a pretreatment device for converting the gas to be detected into a substance indicatable via a colorimetric indicator. The gas measuring device simplifies the detection of fluorine and includes a pretreatment device which has a chloride compound containing a metal of the first or second main groups of the periodic system and is exposed to the fluorine and has a chlorine indicator.

Abstract: Gas samples withdrawn from within a reactor vessel, as well as from the feed gas thereto, are passed to gas analyzers for particular components or impurities desired to be measured. The response time of the reactor analysis system employed is advantageously minimized by the elimination of dead gas space upon the closing of control valves and the provisions for rapid purging of the system or of individual gas analyzer feed lines.

Abstract: A single gas analyzer is used for analyzing the concentration of two gaseous components such as hydrogen and chlorine in a blend by responding to the chlorine content in the gas blend there being a UV-type reactor for the formation of hydrochloric acid and the operation is such that the gas to be analyzed alternates between a path in which the reaction has taken place and one in which such a reaction has not taken place, for directly measuring the concentration of the gas with a higher concentration and indirectly the concentration of the gas with the lower concentration by determining the depletion the reaction has caused in the higher concentration gas.

Abstract: Method of measuring electrolyte concentration in a urine sample, by preparing a calibrating solution containing ions of the electrolytes to be measured, preparing a diluent containing the same ions, diluting the urine sample with the diluent, measuring the electrolyte in the diluted urine with an electrode using the calibrating solution, and calculating the concentration of electrolyte based on the measured value. Additionally, the concentration of the same electrolytes in a blood sample can be measured without dilution, using the same calibrating solution.

Abstract: A process and an apparatus for the detection of molecular or ionic species, comprising:(a) contacting a gaseous or liquid medium containing the species to be detected with a film comprising at least one monomolecular layer of amphiphilic compound chosen from among the tetracyanoquinodimethane (TCNQ) charge transfer complexes and the tetracyanoquinodimethane (TCNQ) salts, which conduct electricity or are precursors of electricity conducting charge transfer complexes and(b) determining the variation of one of the physical properties of the film.It is in particular possible to use layers of TCNQ alkyl-pyridinium, TCNQ alkyl-quinolinium, for detecting iodine, nitrogen oxides and fluoric compounds.

Abstract: A method for the determination of peroxide in a sample is disclosed which comprises reacting the peroxide with a chromogen represented by the general formula (I) or (II) ##STR1## wherein R.sub.1 and R.sub.3 represent amino, mono- or di- substituted amino, hydroxyl or hydroxyalkyl, R.sub.4 and R.sub.5 represent hydrogen, alkyl, alkylene, acyl, halogen, sulphone, nitro, carboxyl, hydroxyl or hydroxyalkyl, R.sub.2 represents hydrogen, ##STR2## wherein R.sub.6 represents hydrogen, alkyl, aralkyl, alkylene, aryl or mono- or di- substituted aryl, and --Z-- may change to --Z.dbd. by resonance and represents --S--, --O--, --N.dbd., ##STR3## wherein R.sub.7, R.sub.8, R.sub.9 and R.sub.10 have the same significance as R.sub.6 in the presence of heme compound, iodide or bromide and measuring the absorbancy of the reaction solution in the visible ray region.

Abstract: Articles comprise transition metal double-complex salts which contain arenyl isonitrile ligands derivatized with long aliphatic chains, the cation being a tetrakis isonitrile platinum ion and the anion being a tetracyanopalladate ion. These double-complex salts exhibit novel vapochromic effects and are useful as personal and badge monitors, threshold monitors, optical waveguide sensors, chemical field effect transistors, and in related monitoring applications.

Abstract: A method for measuring chloride ion concentration in a sample of body fluid, e.g., serum or plasma is described in which a sample blank is made in the same cuvette after the test measurement has been made.

Abstract: An indicator for the documentation of chlorine by discoloration of potassium iodide applied on a support is to be improved so that it is sufficiently sensitive for the documentation of the low chlorine concentrations and also has, for the documentation of high concentrations, a stable dicoloration. To this end it is provided that the indicator comprises an addition of manganese chloride.

Abstract: The invention relates to an analytical method for determining the organic halogen content of a sample. The results of the present method are superior to known methods, and are independent of the physico-chemical properties of the halo-organic compounds in the sample. The method comprises subjecting a sample containing a halo-organic compound, preferably in solution in an aprotic solvent, to electrolysis, and determining the resulting halide ion concentration.