Abstract: A method of detecting the presence or measuring the concentration, of a reactive gas in an inert ambient gas by (i) placing a silicon dioxide film derived from the oxidation of a hydrogen silsesquioxane resin in the inert ambient gas; (ii) passing the inert ambient gas over the film; (iii) monitoring a change in the current flow through the film at a voltage below and above a threshold voltage, as an indication of the presence in the inert ambient gas of a reactive gas; and (iv) determining the threshold voltage of the film as a measure of the concentration of the reactive gas in the inert ambient gas. The silicon dioxide film is characterized by a current-voltage curve which includes both linear and non-linear regions.

Abstract: An oxygen sensor is based on a thin film of a compound oxide supported on a substrate such as quartz. The compound oxide has a general formula ABO.sub.2.5+x, where A is an element of the lanthanum family, alkaline earth metal or their mixture, and B is a transition metal or a mixture of transition metals. X is a variable number, changing from about 0 to about 0.5 between the reversible oxygen-deplete and oxygen-rich forms of the oxide. In an elevated temperature and oxygen-containing atmosphere, the thin film can undergo reversible bulk oxidation resulting in a detectable change of its physical properties such as mass, optical transmissivity and electrical resistance.

Abstract: An oxygen indicator comprising(a) at least one aliphatic organic compound having 3 or more carbon atoms and containing at least one primary amine group and at least one hydroxy group and optionally an organic or inorganic acid or the chemically bonded material of the organic compound and the acid, and(b) at least one dyestuff selected from the group consisting of thiazine dyestuffs, indigo dyestuffs and mixtures thereof is disclosed. The oxygen indicator of this invention can be used under anhydrous conditions and under presence of light.

Abstract: An on-line mass spectrometric method and apparatus for the determination of the isotopic composition of at least oxygen, hydrogen and nitrogen in a compound or mixture of compounds. A mixture contained in syringe 6 is injected through injector 7 on a chromatographic column 1. Compounds eluting from the column 1 pass into a catalytic reactor 14 containing carbon and are decomposed to produce carbon monoxide, molecular nitrogen, and molecular hydrogen. These gases are analyzed by an isotope-ratio mass spectrometer 4 so that the isotopic composition of the oxygen, nitrogen and hydrogen comprised in the original compound can be determined. A second chromatographic column 24 may be provided to separate carbon monoxide and nitrogen before they are passed into the spectrometer 4, thereby allowing a low resolution spectrometer to be used for the analysis of both gases at m/e 28 daltons.

Abstract: The present invention relates to a method and an apparatus for measuring trace quantity of oxygen in a gas by reacting yellow phosphorus vapor and oxygen in a sample gas, and measuring the intensity of the light emitted by the reaction. Together with the sample gas, a constant amount of oxygen is continuously supplied to a reaction chamber so as to react with the yellow phosphorus vapor, and the intensity of the light emitted is measured. The oxygen concentration in the sample gas is determined from the difference between the value measured as above and the intensity of the light emitted by the reaction between the yellow phosphorus vapor and the added oxygen, or from the oxygen concentration obtained from the measured value and the concentration of the added oxygen.

Abstract: A method and apparatus are described for an accurate determination of the concentration of a gas, vapor or a gas dissolved in a sample which compensate for variations in temperature and light - source intensity. The apparatus comprises a sensor containing a fluorescent reagent connected to a transfer optic, such as fiber optics prism or glas pipes, and to a reference sensor containing the same fluorescent reagent. The reference sensor is encapsulated in an environment containing air. The light emitted from the first sensor and the reference sensor is determined and recorded automatically, the concentration of the gas being calculated based on the output from said light detectors using calibration data of the fluorescent reagent present in the sensors. The reagent is immobilized in the sensor by a glue, such as a silicon glue.

Abstract: The present invention relates to a process for the detection or determination of molecular oxygen by EPR spectrometry using radical lithium phthalocyanines and a composition usable for in vivo determination. In the process, a medium is contacted with a radical lithium phthalocyanine in accordance with the formula: ##STR1## in which R.sup.2, R.sup.3, R.sup.6, R.sup.7, R.sup.10, R.sup.11, R.sup.14 and R.sup.15 represent an alkyl or an alkoxy radical group with 1-3 carbon atoms and R.sup.1, R.sup.4, R.sup.5, R.sup.8, R.sup.9, R.sup.12, R.sup.13 and R.sup.16 represent a hydrogen or deuterium atom, and the EPR signal of the radical lithium phthalocyanine in contact with the medium is examined.

Abstract: The concentration of molecular oxygen in a sample is determined by exciting oxygen molecules of the sample from the electronic ground state to the excited .sup.1 .DELTA..sub.g state (excited singlet state), measuring a 1270-nm luminescence characteristic of the excited oxygen molecules (singlet oxygen) and correlating the luminescence characteristic measured with the concentration of molecular oxygen in the sample. Normally, the 1270-nm luminescence characteristic is the 1270-nm luminescence intensity. Preferably, the oxygen molecules are excited by being subjected to diffusion contact with a sensitizer such as a porphyrin or a porphyrin-related compound, e.g. a transition metal complex of a porphyrin. The sensitizer is brought into an oxygen-exciting electronic state by absorption of electromagnetic radiation such as light, the oxygen-exciting electronic state optionally being adapted to the measuring system employed by means of a quencher such as a substituted polyene.

Abstract: The invention is directed to a light producing microemulsion formed in the resence of a surfactant/cosurfactant pair from an oil phase medium having at least an oxalate derivative and a fluorescer compound dissolved in it and an aqueous phase medium containing at least an oxidant dissolved in it. The light produced in such a microemulsion can be used to analyze aqueous oxidant-containing samples by comparing the amount of light produced by a microemulsion formed from a known quantity of an oxidant to a similar sample containing an unknown quantity of an oxidant. The comparison can be made by any well known photosensitive means and can be computerized.

Abstract: A method for measuring oxygen concentration using a probe comprising an immobilized polypyridine metal complex is disclosed, which can be used even in a case where the exciting ray to be used and luminescence are visible rays and which can stably be used even when it is directly immersed in a liquid to be examined without a protective membrane, which makes miniaturization of a probe possible.

Abstract: A dimensionally-stable organosilicon material composition and method for producing the material composition including non-crosslinkable, continuous phase silicone with silica filler material dispersed therethrough, and having dissolved therein a variably-radiative material (e.g., ruthenium dye) responsive to the concentration of a selected analyte (e.g., oxygen), and the products of a reaction between water and a modifier material selected for establishing the sensitivity of said variably-radiative material to the selected analyte.

Abstract: A test device having the following meritorious effects is obtained in accordance with the present invention by using at least one composition selected from the group consisting of ink compositions for detecting glucose, for detecting protein, for detecting urobilinogen, and for detecting occult blood in a body fluid, and for detecting the pH thereof:a) The test device is stable during storage in atmospheric air for a long period of time, presenting no discoloration phenomenon;b) The test device has high sensitivity coupled with excellent measurement performance;c) The regions for detecting glucose and the other body fluid ingredients and the pH can be formed directly on the surface of the test device by printing, allowing the test device to be formed by mass production and the process steps to be reduced; andd) The ink compositions for detecting glucose, etc. are stable, and can be handled easily.

Abstract: A sensor and a method for using the sensor to determine the concentration or partial pressure of oxygen in a fluid media is provided. The sensor includes a light modifying medium containing a luminescent dye which is accessible to oxygen. The luminescent dye contains a hexanuclear core of molybdenum, tungsten or mixtures thereof having 14 coordination sites, wherein each site is occupied by a ligand. The sensor also includes an apparatus capable of transmitting and collecting light to and from the light modifying medium.

Abstract: An apparatus for measuring the amount of oxygen in a sample gas, which is suited for quantifying small amount of oxygen in a sample gas. The apparatus of the present invention comprises a yellow phosphorus vapor-providing section in which yellow phosphorus is retained, by which the vapor of the yellow phosphorus is supplied and by which the amount of the vapor of the yellow phosphorus is controlled. The apparatus further comprises a reaction chamber connected to the yellow phosphorus vapor-providing section, in which the light-emitting reaction between the oxygen in the sample and the vapor of the yellow phosphorus is conducted, and a sample gas-supplying section. The amount of the oxygen in the sample gas is determined by measuring the intensity of the light emitted by the reaction by a light intensity-measuring device.

Abstract: The system for measuring the concentration of oxygen in a fluid sample which may also contain halothane includes a sensor having a matrix containing a first indicator dye which fluoresces at a known wavelength when irradiated with light of a specific wavelength and containing a second indicator dye which fluoresces at a different emission wavelength upon irradiation with light of a similar or different specific wavelength. The fluorescence of the first and second indicator dyes are quenched to a different degree by the presence of oxygen, but the fluorescence of the indicator dyes is quenched to the same degree by halothane. Means are provided for irradiating the indicator dyes in the matrix with the appropriate wavelengths of light, and means are provided for measuring the resultant intensity of fluorescence of the indicator dyes at the different wavelengths of fluorescence.

Abstract: The optical detection of the concentration of a specific substance in a liquid or a gas by the utilization of the quenching of a phosphor by the specific substance or a substance derived from the specific substance is attained with high accuracy by a method and apparatus which comprises causing the system of determination to induce the presence of a first phosphor (A) quenchable by the specific substance or a substance derived from the specific substance and a second phosphor (B) substantially unquenchable by the specific substance or a substance derived from the specific substance, measuring the light signal corresponding to the intensity (I.sup.f.sub.A) of emission from the first phosphor (A) and the light signal corresponding to the intensity (I.sup.f.sub.B) of emission from the second phosphor (B), and calculating the ratio between the light signals thereby offsetting variable factors relative to the intensities of emission.

Abstract: Oxygen in carbonaceous materials is converted to carbon monoxide (CO) by pyrolyzing the material in a stream of oxygen-free helium. The CO is reacted with Ni.sup.63, a readioactive isotope of nickel, to form nickel tetracarbonyl (Ni.sup.63 (CO).sub.4) which is carried by the helium stream into a flow-through gas proportional counter. The quantity of Ni(CO).sub.4 is determined by the radioactivity of the gas as measured by the gas proportional counter. After exiting the flow through counter the Ni.sup.63 (CO).sub.4 is destroyed by exposing it to high temperatures. The Ni.sup.63 is retained within the apparatus while the CO is flushed from the system after being oxidized to carbon dioxide (CO.sub.2). The detection limit is estimated to be less than 1 part per billion oxygen for a 10 mg sample.

Abstract: Method for making a probe with a plurality (one or more) of optical fiber sensors containing colorimetric chemical indicators in gaps in the fibers, the fibers bent to provide good light transmission qualities. Apparatus for making a probe with a plurality of such optical fiber sensors. A probe with a plurality of such optical fiber sensors. A vacuum chuck for holding the ends of such fibers.

Abstract: Improved process control is achieved in processes for which it is useful to control variable process conditions based upon on-line determinations of the concentration of weak acids and weak bases, or their soluble salts, in liquid streams of the processes. For example, amine system energy savings and waste treatment system control improvements are taught.

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: Packages which are subject to tampering while in a store or deterioration over time due to the presence of oxygen may be readily identified by placing therein a multi-component visual indicator system which is sensitive to the presence of oxygen. The system, which may be prepared aerobically and then placed into an anaerobic environment for use, is not effected by the presence of reducing agents found commonly in foods, drugs, and cosmetics.

Abstract: The analyte sensing system utilizes a sensor indicator which may be a perlyene derivative, coronene, or naphtho [8,1,2-abc] coronene in an analyte permeable silicone matrix. The matrix is irradiated with light of a specific wavelength, and fluorescence emissions of the dye indicator is measured over two different emission spectra having different sensitivities to the analyte. The emission spectrum which is less sensitive to quenching by the analyte can be used as a reference for determining the analyte concentration based upon a ratio of the intensities of the different emission spectra.

Abstract: A method and apparatus for testing for the presence and concentration of contaminants in a refrigerant. A sample of the refrigerant is withdrawn from a closed refrigeration, air conditioning or similar system and passed through a testing tube. Various sections of the tube contain provisions for the removal of oil entrained in the sample, for the removal of water contamination from the sample and for providing visual indications of the presence and concentration of a plurality of contaminants that may be present in the refrigerant.

Abstract: Silicic acid heteropolycondensates containing a luminescent compound, whose luminescence is quenchable by oxygen, form suitable sensors for measuring oxygen content in an oxygen-containing gaseous, liquid, or solid sample.

Abstract: This invention is a method and apparatus for detecting the presence of gaseous oxygen and measuring the amount present. In the practice of the invention, luminescence from a luminophor compound is quenched by oxygen. The luminiphor is a conjugated aromatic carbonyl. The intensity of the emitted light is related to the concentration of oxygen in the atmosphere surrounding the conjugated aromatic carbonyl compound. The luminophor compound is located on a polar substrate having free hydroxyl groups at its surface and also having at its surface, in locations adjacent to the luminophor compound, a halogenated hydrocarbon compound containing at least one halogen selected from a group consisting of chlorine, bromine, and iodine. In a preferred embodiment, the invention comprises an oxygen sensor utilizing a fiber-optic light guide to conduct excitation light to a substrate comprised of activated silica gel particles having methylene chloride and N-methylacridone co-deposited on them.

Abstract: Methods of and luminescent substances for measuring oxygen concentration of a test fluid. A test fluid is contacted with a plastic film containing a luminescent substance, the luminescent emission intensity of which is quenched in the presence of oxygen. The film is subjected to irradiation by light that is strongly absorbed by the luminescent substance, and a measure of the time dependence of luminescent emission intensity I(t) is obtained. Three modes of measuring quenching, and thus the oxygen concentration, from I(t) are described. These modes are insensitive to variation in plastic thickness, concentration of the luminescent substance, and take into account the non-exponential decay of the emission, thereby extending the range over which the film is sensitive. The luminescent substances include metallo derivatives of partially or fully fluorinated porphyrins which are photostable due to the fluorination of the porphyrin ring.

Abstract: An optical pH sensor and a gas sensor utilizing the pH sensor. The pH sensor includes an indicator whose absorbance is a function of the concentration of hydronium ions in a media surrounding the indicator. Light transmitted and reflected through the indicator of the sensor undergoes an absorption that is characteristic of the concentration of the hydrogen ion. The pH sensor can be used as to sense the concenration of a gas in a sample by surrounding the indicator with a liquid or liquid-containing media that changes pH as it is exposed to the gas, and separating the indicator and liquid or liquid-containing media from the gas with a membrane that is permeable to the gas to be measured. A measuring system used with the sensors transmits coherent radiation to the sensor through an optical fiber, separates the radiation returning from the sample into two wavelength bands, and digitally samples the photocurrents produced within the two wavelength bands.

Abstract: An oxygen sensor contains an indicator whose change in absorption is a function of the concentration of oxygen in a sample bathing the indicator. Light transmitted and reflected through the indicator of the sensor undergoes an absorption that is characteristic of the concentration of oxygen. The indicator is a viologen whose absorption returns to a steady-state value after it has been subjected to a pulse of short-wavelength light. The rate at which the absorption returns to the steady-state value is a function of the concentration of oxygen bathing the viologen indicator. A measurement system for use with the pO.sub.2 sensor causes a short-wavelength flash to be sent to the sensor and thereafter monitors the time-varying absorption of the sensor to measure the oxygen content of the sample bathing the viologen indicator.

Abstract: Quenching luminescence of the tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) perchorate, immobilized in a silicone rubber by oxygen is shown to be an accurate and precise method for measuring oxygen concentration in solutions and in the gas phase. Quenching can be quantitated by either lifetime or intensity quenching measurements. Strong aqueous acids and bases, complexing agents, oxidants, and reductants do not penetrate the hydrophobic polymer and, therefore, do not affect the response. Gaseous interferents, such as H.sub.2 S, anesthesia gases (e.g. N.sub.2 O, Halothane), and fluorocarbons do not affect the response. Chlorine and especially SO.sub.2 cause strong, but reversible interference presumably because of electron transfer quenching. A system with a response time of less <0.2 s is disclosed, which is adequate for the monitoring of breathing subjects.

Abstract: A method for measuring the amount of oxygen in a sample gas is suited for quantifying small amount of oxygen in a sample gas. The method of the present invention comprises reacting the oxygen and vapor of yellow phosphorus under a vapor pressure of the yellow phosphorus which is lower than the saturated vapor pressure of the yellow phosphorus at room temperature; and measuring the intensity of light emitted by the reaction. The amount of the oxygen in the sample gas is determined by measuring the intensity of the light emitted by the reaction by a light intensity-measuring device.

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: Method and device for determining the respiration rate of a respiring material such as active sludge in a continuous process flow before and after holding thereof in a respiration chamber. The oxygen content in the continuous process current is done at a single measurement point. This is done by reversing the incoming and outgoing current of the respiration chamber. Preferably the process flow consists of a mixture of respiring material and waste water to be biologically purified.

Abstract: A method for monitoring the glucose level in a body fluid uses an apparatus which includes a conjugate of glucose oxidase and a fluorescent dye coated onto an optical fiber in contact with the body fluid, a source of excitation light and a fluorescence emission detector. Glucose is oxidized by oxygen in the body fluid causing a decrease in oxygen concentration at the enzyme. The fluorescent dye is sensitive to oxygen quenching so that, when the oxygen concentration decreases, fluorescence emission increases in direct proportion to the glucose concentration in the fluid.

Abstract: A sensor and a method for determining the concentration or the partial pressure of oxygen comprising:(a) means for transmitting and collecting light to and from a light modifying medium; and(b) a light modifying medium containing a luminescent dye dispersed in or upon a matrix and the dye is accessible to oxygen, wherein said luminescent dye contains a hexanuclear core of molybdenum, tungsten or mixtures thereof having 14 coordination sites, wherein each coordination site is occupied by a ligand.

Abstract: A method for monitoring the glucose level in a body fluid uses an apparatus which includes a conjugate of glucose oxidase with a fluorescent dye coated onto an optical fiber in contact with the body fluid, a source of excitation light and a fluorescence emission detector. Glucose is oxidized by oxygen in the body fluid causing a decrease in oxygen concentration at the enzyme. The fluorescent dye is sensitive to oxygen quenching so that, when the oxygen concentration decreases, fluorescence emission increases in direct proportion to the glucose concentration in the fluid.

Abstract: A method and apparatus for rapid analysis of a sample medium, particularly a flowing sample medium employ light of a defined wavelength which is guided onto a luminescent layer in contact with the sample medium, the luminescent properties of the layer varying in dependence upon characteristics of the sample medium which are to be analyzed. The luminescent light is monitored by detectors, the detector signals being a measure for the characteristic of interest. For undertaking identification of a particular characteristic with very short follow-up time, even in the presence of a number of other characteristics which influence the luminescent properties, the luminescent intensity is identified for a number of different wavelength regions corresponding in number to the number of characteristics, each characteristic differently influencing the luminescent properties in at least one wavelength region.

Abstract: An improved oxygen analyzer device is disclosed which comprises a gas flow passage having inlet and exhaust ports, an oxygen concentration detector in proximity to the exhaust port and first and second parallel intermediate flow passages, one of which contains a purifier to remove oxygen from the gas flowing therethrough. The device is characterized by the use of metal, diaphram-type, three-way valves in the branch-off and junction points between the intermediate flow passages. The valves eliminate dead space in conventional devices that extends both the calibration and analysis time of such devices.

Abstract: Novel adducts of oxazine urea chromophors or thiazine urea chromophors with organic substrates are provided which are useful in analytical techniques for the detection and measurement of biological and clinical compounds of interest.

Abstract: An oxygen sensor is provided for determination of the partial pressure of oxygen. In one aspect, the invention consists of oxygen-quenchable luminescent lanthanide complexes for an oxygen sensor. The complexes are oxygen-quenchable even though immobilized in a solid matrix, such as a solid polymeric matrix, and preferably are terbium complexes of Schiff base or .beta.-diketone ligands. Certain preferred processes are described for improving the oxygen sensitivity of the lanthanide complexes. In another aspect, the invention consists of a combination measuring and reference analyte sensor containing both quenchable and nonquenchable luminescent materials. The materials luminesce at different wavelengths and thus may be transmitted together down a single optical fiber and later descriminated by means of filters and separately detected. In a third aspect, the invention consists of a low-noise phosphorescent analyte sensor employing a gatable detector.

Abstract: An optical sensor which is a gas permeable silicone polymeric matrix having at least one optical indicator therein for providing an optical signal in response to excitation light. The optical indicator essentially comprises a mixture of non-polar derivatives of a polynuclear aromatic compound.

Abstract: Methods and compositions are described for measuring oxygen concentration, particularly for monitoring oxygen in the blood with a fiber optic catheter. Oxygen concentration is determined by observing quenching of the emission from a luminescent (phosphorescent of fluorescent) molecule embedded in an oxygen-permeable matrix. A test fluid of unknown oxygen concentration is contacted with the matrix containing at least one luminescent substance. The matrix is subjected to irradiation over some period of time by light of a wavelength that is strongly absorbed by the luminescent substance, and a measure of the time dependence of luminescent emission intensity I(t) is obtained. Three modes of determining oxygen concentration from I(t) are described.

Abstract: A method for marking/sorting semiconductor wafers in accordance with predicted values of oxygen precipitation in the wafers that will occur after the performance of a thermal process step. In a preferred embodiment, this oxygen precipitation prediction is obtained by means of a correlation equationY=A.sub.o +A.sub.1 OX.sub.i +A.sub.2 /LT+A.sub.3 C+A.sub.12 OX.sub.i /LT+A.sub.13 OX.sub.i C+A.sub.23 C/LT,where OX.sub.i is the value of interstitial oxygen in the wafer measured prior to the thermal process step, LT is the minority carrier lifetime for the wafer measured prior to the thermal process step, and C is the initial substitutional carbon in the wafer measured prior to the thermal process step. The constants A.sub.0, A.sub.1, A.sub.2, A.sub.3, A.sub.12, A.sub.23, and A.sub.13 are initialized on a first sample of wafers representative of a desired range of crystal types.

Abstract: A luminescent layer for use in apparatus for determining the oxygen concentration in gases, fluids and tissues by measuring the decrease in the light emission of a luminescent surface irradiated with an excitation light of a certain wavelength, where the luminescent dye forms a homogeneous mixture with the light-transparent layer substance, in which case the surface may also have a fine-grained structure.

Abstract: The present invention relates to compositions useful for the detection of oxygen in a humid medium, characterized in that they comprise at least one complex of the formula (LMX).sub.n in which the ligand L is selected from among the groups: ##STR1## where: R represents Cl,Br,NO.sub.2,C.sub.1-4 -alkoxyl, C.sub.1-4 -alkyl,m and p are comprised between 0 and 3,q is comprised between 0 and 2,the substituent R on the pyridine nuclei never occupying a position neighboring the nitrogen atom,X=Cl,Br,I,NO.sub.3,C10.sub.4,M represents Cu or Mn, andn is equal to 1 or 2,as colored indicator of the presence of oxygen in a humid medium, in solution in an acceptable solvent.The present invention also relates to a process for preparing such compositions, and detectors of the presence of oxygen comprising them.

Abstract: Disclosed is an apparatus for measuring the moisture content of a sample. The apparatus includes a first sealed chamber for accepting the sample and a first impulse furnace within the first chamber for dissociating water in the sample into the hydrogen and oxygen, a second sealed chamber in gaseous communication with the first chamber, a second impulse furnace within the second chamber for dissociating water and the hydrogen and the oxygen, and a hydrogen analyzer for determining the amount of hydrogen formed by the first and second impulse furnace. Also disclosed is a method of measuring the amount of water in the sample. The sample is heated in an enclosed chamber in the presence of a water dissociation catalyst, whereby water in the first chamber is dissociated into hydrogen and oxygen. Vapors are passed from the enclosed chamber to a second enclosed chamber which contains a water dissociation catalyst, whereby water in the vapors is dissociated into hydrogen and oxygen.

Abstract: The present invention relates to a novel method and apparatus which can provide continuous monitoring of the oxygen content of a gas over an indefinite period of time and at a minimal cost.In the novel apparatus of the present invention, a light source and a light sensitive detector are disposed within the atmosphere to be measured, and a polymeric film formed from a manganese tertiary phosphine polymer complex is deposited between the light source and the detector. As oxygen pressure increases or decreases a change in color intensity of the film takes place which controls passage of light from the light source to the detector. The detector in turn is suitably connected to an audio and/or visual warning device and/or a recorder which will provide the desired form of warning.

Abstract: A trimode gas detection instrument having three operating modes, one which monitors the level of combustible gases, a second which monitors oxygen, and a third which monitors the displacement of air by an unknown gas. Only two sensors are used, a combustible gas sensor and an oxygen sensor. A switch selects the input to a readout so that the user can quickly observe the concentration readings in any of the three modes. In the depletion mode the readout is calibrated in relation to the inverse of the normal concentration of oxygen in air--i.e., zero depletion corresponds to an oxygen concentration of 21%. In the event that an unknown gas displaces air in a sample atmosphere, concentration of the unknown gas appears on the readout, such that zero oxygen corresponds to a concentration of 100% unknown gas.

Abstract: In an O.sub.2 sensor element which contains a fluorescent indicator substance, a polymerized silicone polymer is used as a carrier material in which the indicator substance is incorporated in solubilized form and in an at least approximately homogeneous distribution. Solubilization of the indicator substance may essentially be performed in analogy to Friedel-Crafts alkylation of aromatics, which will increase solubility of the indicator substance in the polymer carrier without affecting quenching behavior.

Abstract: Method and apparatus which can provide continuous monitoring of the partial pressure of one or more gases in an atmosphere or feed stream, over an indefinite period of time and at a minimal cost. The method and apparatus of the present invention operates by monitoring the change in frequency of a piezoelectric element which has been coated with a film formed from manganese tertiary phosphine polymer complex. As the polymer absorbs or releases gas the frequency of the piezoelectric device will be altered.

Abstract: Materials of oxygen ion conductors comprising CeO.sub.2 -CaO type oxides wherein 5-60 mol % of CaO is mixed with CeO.sub.2 having a fluorite structure, and composite oxides wherein CeO.sub.2 of said CeO.sub.2 -CaO type oxides is replaced by oxide of magnesium or aluminum by 5-10 mol %.