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: An electrochemical method for determining the total carbonate content of fluids, especially biological fluids. According to the invention, using an ion-selective electrode, the concentration of certain ions dissociable from carbon acid or affecting the dissociation balance is first measured for the fluid. The fluid is then mixed with another fluid containing a reactive component that changes the ionic concentration just measured, whereupon the concentration is again measured by means of an ion-selective electrode, thus producing two different measurement results, from which the total carbonate content can be determined. The measurement preferably relates to the pH of the fluid, while metallic ions such as Cu.sup.2+, forming a complex with hydrocarbonate ions, are used as the component to be added to alter the pH.

Abstract: A detector for rapid response, quantitative determination of carbon dioxide in a gas comprising one or more components, each of which comprises a carrier with a surface to be exposed to the gas, said surface including ane indicating element of a predetermined sensitivity which gives a rapid response signal when exposed to a given concentration of carbon dioxide, the response signals produced when the component or components are exposed to the gas providing a rapid and progresssive quantitative determination of the concentration of carbon dioxide or any change with time of said concentration in the gas.

Abstract: A method is described for the quantitative measurement of traces of gas, particularly CO.sub.2 and CH.sub.4 which constitute impurities in impure inert gases such as rare gases and nitrogen, by means of the use of a known analyzer for reducing gases which uses a bed of mecuric oxide and makes the measurement by an optical method of the mercury vapors produced which are proportional in to the concentration of the impurities to be detected. The method of the present invention subjects the impure inert gas to an electric discharge which may be at a high voltage, capable of ionizing the impurities before the impure inert gas is made to pass through the bed of mecuric oxide. The device according to the invention comprises, between a gas-chromatographic separation column and the analyzer, an electrode within a passage through which flows the gas to be analyzed and in which there is an ionizing discharge.

Abstract: A sensor for determining the partial pressure of carbon dioxide in a liquid, which comprises a carbon dioxide - permeable, liquid and ion-impermeable membrane enveloping an aqueous medium containing an absorber, a fluorescer and a source of bicarbonate ions, which medium exhibits variations in pH as a function of the partial pressure of dissolved carbon dioxide, the ratio of absorber to fluorescer and the characteristics of the absorption spectrum of the absorber and the excitation and emission spectra of the fluorescer being such that the partial pressure of carbon dioxide in the liquid may be determined from the pH of the aqueous medium as measured by the intensity of the fluorescent emission of the fluorescer.

Abstract: A method of measuring the concentration of carbon dioxide in a medium by determining the water content in a pH-independent sensor system comprising an optical fiber having attached thereto a fluorescence indicator embedded in a carrier matrix containing a miscible mixture of water and non-aqueous solvent in predetermined proportions and being separated from said medium by a gas-permeable, water-impermeable diffusion membrane, said indicator, when excited by excitation radiation of a predetermined wavelength, emitting fluorescent emission whose intensity is dependent upon the ratio of water to non-aqueous solvent present in the system such that the ratio of intensities of emitted radiation is therefore proportional to the amount of water present and diffusion of carbon dioxide through said gas-permeable membrane and subsequent reaction with water to deplete the water content of the system induces a change in the intensities of said emissions, which method comprises transmitting excitation radiation through sai

Abstract: A system for the detection of trace components in a gas by a process involving the ionization of such trace components and intermittently adding to the gas, a reactant gas which converts some of the components to more readily ionizable forms.

Abstract: A gas sensor has a first aqueous phase. The aqueous phase is composed of a soluble dye in a buffer. One or more additional agent can be further added to the aqueous phase as for instance an emulisification enhancement agent. The aqueous phase is homogenized into a polymeric precursor forming a emulsion of the aqueous phase in the polymeric precursor. A catalyst and a cross-linking agent are added and the polymeric precursor material allowed to polymerize to form an emulsoid of micro-compartments of the aqueous phase in a polymeric second phase. The micro-compartments of the aqueous phase are dispersed through and permanently suspended in the polymeric second phase.

Abstract: A continuous on-line monitor of carbon dioxide dissolved in high purity water includes a cation conductivity cell and associated bridge for measuring first and second cation conductivities at first and second temperature and a heater for heating the sample from the first to the second temperature. A microcomputer calculates first and second concentrations of a fully dissociated acid alone and carbon dioxide alone, respectively, which will produce the first measured cation conductivity at the first temperature and then determines the actual carbon dioxide concentration from the first and second concentrations and the second measured cation conductivity.

Abstract: The presence of carbon dioxide contained in a gas can be detected through measurement of the change in the electrical resistance of a hydroxyapatite in contact with carbon dioxide gas. The sensitivity of the hydroxyapatite to carbon dioxide gas can be enhanced by the formation of a composite of the hydroxyapatite with an inorganic carbonate, e.g., sodium carbonate or calcium carbonate. The sensitivity to carbon dioxide gas can be further enhanced by the formation of a composite of the hydroxyapatite with an inorganic halide, e.g., calcium chloride.

Abstract: A method for determining the presence of an amount of sodium vanadate, in an aqueous solution containing the same which may also contain one or more sodium acid carbonate, sodium carbonate, sodium thiosulfate, anthraquinone disulfonic acid, sodium sulfate, various acid gases (e.g. H.sub.2 S, CO.sub.2, COS and the like) and hydrocarbon liquid and gases such as would be expected in a Stretford gas treating solution, the improvement which comprises passing the solution to be analyzed into and through an anion exchange guard column then through a brine sensitive medium capacity ( 0.05 meq./gm) hydrophobic anion exchange column eluting the columns with a 0.001 M Na.sub.2 SO.sub.4 /0.

Abstract: An optrode is provided for sensing dissolved gases or volatile components of a solution. A fiber optic is provided through which light from an associated light source is transmitted from a first end to a second end. A bubble forming means, such as a tube, is attached to the second end of the fiber optic, and an indicator material is disposed in cooperation with the bubble forming means adjacent to the second end of the fiber optic such that it is illuminated by light emanating from the second end. The bubble forming means causes a gas bubble to form whenever the optrode is immersed in the fluid. The gas bubble separates the indicator material from the fluid. Gases, or other volatile components, of the fluid are sensed as they diffuse across the gas bubble from the fluid to the indicator material.

Abstract: A solid detecting reagent for gaseous hydrides and a gaseous hydride detecting method are disclosed, said reagent comprising a basic copper carbonate as a color changing component and undergoing color change upon contact with at least one gaseous hydride selected from the group consisting of arsine, phosphine, diborane, hydrogen selenide, germane, monosilane, disilane and dichlorosilane. The reagent is applicable to all of these gaseous hydrides and, upon contact therewith, rapidly changes from an initial blue color to a black color, said black color standing for a long period of time.

Abstract: A method for continuously measuring the concentration of CaCO.sub.3 in slurries comprising CaCO.sub.3 is described. The method comprises continuously sampling a given amount of the slurry, feeding the sampled slurry into an agitated continuous reactor container which is isolated from the outside air, keeping the slurry in the reactor container at a temperature of at least 50.degree. C., adding sulfuric acid or hydrochloric acid to adjust the pH to below 4, blowing a known flow rate of air into the slurry, withdrawing from the reactor container CO.sub.2, produced by the reaction between CaCO.sub.3 and the acid, by entrainment with the air, further mixing the withdrawn gas with air for dilution while controlling a flow rate of the dilution air so that the concentration of CO.sub.2 in the mixed gas is maintained constant, and calculating the concentration of CaCO.sub.3 in the slurry from the concentration of CO.sub.2 in the mixed gas, the flow rate of the mixed gas and the amount of the sampled slurry.

Abstract: A method for continuously measuring the concentration of CaCO.sub.3 and/or CaSO.sub.3 in slurries comprising CaCO.sub.3 and/or CaSO.sub.3 is described. The method comprises continuouly sampling a given amount of the slurry, feeding the slurry into an agitated continuous reactor container which is isolated from the outside air and in which the slurry is kept at a temperature not lower than 70.degree. C., adding sulfuric acid or hydrochloric acid to the slurry to make the pH below 3, blowing air or nitrogen gas into the slurry in the reactor container, withdrawing from the container CO.sub.2 and/or SO.sub.2 produced by reaction of CaCO.sub.3 and/or CaSO.sub.3 with the acid by entrainment with the air or nitrogen gas, and calculating the concentration of CaCO.sub.3 and/or CaSO.sub.3 from the concentration of CO.sub.2 and/or SO.sub.2 in the withdrawn gas, the flow rate of the sampled slurry and the flow rate of the blown air or nitrogen gas.

Abstract: A method for continuously measuring the concentration of CaCO.sub.3 in slurries comprising CaCO.sub.3 is described. The method comprises continuously sampling a given amount of the slurry, feeding the sampled slurry into an agitated continuous reactor container which is isolated from the outside air, keeping the slurry in the reactor container at a temperature of at least 50.degree. C., adding sulfuric acid or hydrochloric acid to adjust the pH to below 4, blowing air into the slurry in the reactor container, withdrawing from the reactor container CO.sub.2, produced by the reaction between CaCO.sub.3 and the acid, by entrainment with the air, and calculating the concentration of CaCO.sub.3 in the slurry from the concentration of CO.sub.2 in the withdrawn gas, the amount of the sampled slurry and the flow rate of the blown air.

Abstract: A solution or slurry containing a carbonate or sulfite, or both is continuously supplied into a tightly closed vessel, while any excess of the liquid is allowed to overflow the vessel. Sulfuric acid is supplied into the vessel to maintain the pH level of the liquid in the vessel at a value not exceeding 3. Air is supplied into the vessel as a carrier gas for CO.sub.2 or SO.sub.2 or both formed by the reaction of the carbonate or sulfite or both in the liquid with the sulfuric acid. The carrier gas is collected from the vessel, and the concentration of CO.sub.2 or SO.sub.2 or both in the carrier gas is determined. The concentration of the carbonate or sulfite or both in the liquid is obtained by calculations from the concentration of CO.sub.2 or SO.sub.2 or both, the flow rate of the liquid and the flow rate of the carrier gas.

Abstract: A fluorescence-based optical sensor includes a membrane immobilized fluorophor secured to one end of a bifurcated fiber optic channel for exposure to the sample to be analyzed. The fiber optic channel also has an input end coupled to a radiation source arranged to supply radiation at two different wavelengths and an output end coupled to a bandwidth limited photosensor. The radiation source alternately excites the fluorophor at a first wavelength that excites an acid form of the fluorophor and at a second wavelength that excites a base form of the fluorophor, and a ratio of the resulting fluorescence intensities is taken as a measure of a characteristic of the sample being analyzed.

Abstract: The specification discloses an analyzer for determining the carbon, hydrogen, and nitrogen content of an organic material. The analyzer includes a vertically oriented, U-shaped furnace including a combustion chamber containing a crucible in which the sample is combusted into constituent gases and a reagent chamber containing a reagent through which the constituent gases must pass. A lance extends into the combustion chamber to guide the sample into the crucible and to direct oxygen onto the sample combusting in the crucible. The analyzer further includes an equilibration vessel and means for conveying the constituent gases to the vessel and past CO.sub.2 and H.sub.2 O infrared cells to monitor the products of combustion. Means are provided for conveying the equilibrated gases past the infrared cells to obtain readings relating to carbon and hydrogen content. A doser doses an aliquot of the equilibrated gas into a nitrogen measurement apparatus to obtain a reading relating to nitrogen content.

Abstract: Process for analyzing anions in a liquid by means of an ion exchanger and by complex formation with specific anions by addition of polyhydric alcohol. Sensitivity is increased owing to the fact that the complex of specific anions with polyhydric alcohol has a high activity as acid.

Abstract: A method of geochemical prospecting for buried sulphur mineralization which comprises collecting relatively organic free soil samples and determining the carbon isotope composition of the carbonate fraction.

Abstract: In order to simplify the operation for determination of the acid-base status of blood, composed of the values for pH, pCO.sub.2 and the base excess BE, the base excess BE is determined through measurement of the pH-value at a pCO.sub.2 of about 0 mm Hg. The pH-values may be determined photometrically, in which case the indicator solution for measuring the actual blood-pH is an aqueous solution of 40 micromol/l bromthymol blue plus 0.2 g/l sodium dodecylsulfate plus 1% ethanol; and for measurement of the base excess BE is an aqueous solution of 65 micro mol/l naphtholphthalein plus 0.2 g/l sodium dodecylsulfate plus 15% dimethylsulfoxide, which are measured at a wavelength of 635 nm. If desired, one may use a single solution for measuring both actual blood-pH as well as the base excess BE, composed of 16 micromol/l bromthymol blue plus 34 micromol/l naphtholphthalein plus 0.15 g/l sodium dodecylsulfate, which is measured at 615 nm wavelength.

Abstract: Apparatus for investigating the performance of a catalyst used in a catalytic cracking process includes a single fluidized bed reactor charged with the catalyst to be investigated and a digital computer which controls the supply of hydrocarbon feed stock and regenerating air in successive and repeated catalytic cracking intervals and catalyst regeneration intervals.

Abstract: A method for determining the concentration of carbonate salts in solutions containing other inorganic salts. The method includes converting the carbonate salts to carbon dioxide by acidifying the sample, sweeping the acidified solution with an inert gas to strip the carbon dioxide from the solution and contacting an ion-selective gas-sensing electrode with the gas stream. The electrode includes a buffered solution which changes in pH depending on the concentration of carbon dioxide in the gas stream thereby providing a measure of the carbonate salt concentration in the sample.

Abstract: An in situ oil shale retort is formed in a subterranean formation containing oil shale. The retort contains a fragmented permeable mass of particles comprising kerogen and various inorganic carbonates. A processing zone is established in the fragmented mass of formation particles and advanced therethrough. Off-gas, including carbon dioxide from carbonate decomposition, is withdrawn from the retort. The carbon dioxide content of the withdrawn off-gas, being a function of the processing zone temperature, is then determined. The determined carbon dioxide content of the withdrawn off-gas is then compared to values of carbon dioxide content of off-gas predicted as a function of processing zone temperature.

Abstract: A method and an arrangement for measuring the concentration of gases in a sample includes the generation of a monochromatic light beam having predetermined color characteristic. An indicator generates light signals indicative of the concentration of the gases in a sample to be measured and includes a light-transmissive surface positioned to be impinged by the monochromatic light beam, a diffusion membrane adapted to be placed in the proximity of a sample and being permeable to a selected gas component thereof, and an indicating substance positioned to be impinged by the monochromatic light beam penetrating the light-transmissive surface and by the gas component penetrating the diffusion membrane. The indicating substance reacts when illuminated by the incident monochromatic light by emitting a resultant light beam having an emitted component which has a color characteristic different from the predetermined color characteristic of the monochromatic light beam.