Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: A process and apparatus for automatically monitoring or adjusting, or both, the concentration of total reducers (i.e. reduced sulfur-containing constituents which consume iodine) in an aqueous medium (e.g. waste water stream) whereby the time period for iodine titration of an untreated sample of the aqueous medium is automatically measured by measuring a time of light being transmitted through a titration sample cell and this time measurement is automatically translated into an output signal to either a monitoring means or a process adjustment means (e.g. oxidant chemical feed pump) or both.

Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: The total sulfur content of samples consisting of chemical compounds is determined by the use of gas chromatographic separation of the sulfur and its flame-photometric detection. The samples are subjected to a catalytic reaction in a pipe reactor before the separation whereby all sulfur-containing compounds are completely converted into hydrogen sulfide. The pipe reactor is made from an aluminum oxide material in a purity of at least 99.8% of the corundum type.

Abstract: A selected component of a fluid mixture, for example a reduced sulfur compound vapor in air, is detected by selectively adsorbing the component onto a conductive thin layer of material having a chemical affinity for such component and observing the resultant change of electrical resistivity of the layer. The sensitivity of the detector changes with accumulation of the component on the sensor. The accumulation of the component on the sensor is removed by oxidizing and evolving the component from the sensor to restore the sensor to a linear operating region. The accumulated component is preferably oxidized by reacting the component with ozone. The dynamic range of the sensor is increased by counteracting the tendency for the component to accumulate by continuously feeding back ozone to or controlling the temperature of the sensor so that the sensor operates in a linear region near null.

Abstract: A method of determining sulfur loading of an organic polysulfide composition comprises reacting the organic polysulfide composition with an organic phosphine to produce reaction products comprising organic phosphine sulfide and an organic sulfide selected from the group consisting of organic disulfide, organic trisulfide and mixtures thereof; and analyzing the reaction products by gas chromatography to determine the amount of sulfur.

Abstract: A process and apparatus for automatically monitoring or adjusting, or both, the concentration of total reducers (i.e. reduced sulfur-containing constituents which consume iodine) in an aqueous medium (e.g. waste water stream) whereby the time period for iodine titration of an untreated sample of the aqueous medium is automatically measured and this time measurement is automatically translated into an output signal to either a monitoring means or a process adjustment means (e.g. oxidant chemical feed pump) or both.

Abstract: Methods and apparatus are provided for decomposing and analyzing a sample for sulfur. The methods combust a nebulized sample in an oxygen-rich atmosphere and then analyze the combustion gases for sulfur. The apparatus employs a nebulizer operatively connected to a combustion tube and employs appropriate detector(s) to analyze the combustion gases from the combustion tube for sulfur.

Abstract: High molecular weight hyaluronic acid can be efficiently produced by incorporating one or more compounds having at least one aromatic ring to which one or more hydroxyl groups are attached into a medium for producing hyaluronic acid by a bacterium capable of producing hyaluronic acid. By using this method, a sufficient amount of hyaluronic acid can be easily obtained without decomposing the high molecular structure of hyaluronic acid so that the process for isolating and purifying hyaluronic acid from the medium can be simplified.

Abstract: A process for the rapid extraction, separation, and detection of free and total sulfites in food is disclosed. The process comprises the steps of (a) extracting sulfites from a sample in the presence of a medium having a selected pH to produce an extractant; (b) filtering the extractant; (c) subjecting the filtered extractant to anion exclusion chromatography to produce a sulfite-containing effluent; and (d) detecting the proportion of sulfites in the effluent. The process may be used either to determine free sulfites (by performing extraction in the presence of an acid medium), or to determine total sulfites (by performing extraction in the presence of an alkaline medium). The process of the present invention may be used to determine sulfite levels of 1.0 ppm or less.

Abstract: In the illustrated and preferred embodiment of this disclosure, a chemiluminescent sulfur detector, both method and apparatus, for detecting bonded sulfur in compounds is disclosed. The illustrated and preferred embodiment, being provided with a discrete sample, passes the sample through a first furnace in the presence of a carrier of inert gas and is exposed to a suitable granulated metal oxide, such as copper oxide or vanadium pentoxide, resulting in oxidation of the sulfur compound. The sample is then passed through a second furnace comingled with elemental hydrogen, there being a conversion of sulfur oxides to hydrogen sulfide. The output of the second furnace is dried. The hydrogen sulfide, along with the inert carrier gas, is introduced into a reaction chamber and is mixed with ozone. A chemiluminescent reaction occurs in the chamber, and the resulting light emission is measured photoelectrically by either a photomultiplier tube or photodiode.

Abstract: An analyzer for natural gas to determine the existence of and concentration of wanted and unwanted sulfur compounds and odorizing agents.

Abstract: A gas chromatographic apparatus is provided which comprises a gas chromatography column, a detector and an extended conduit between the column and the detector, the conduit providing means for flow of a gas so as to enable essentially complete elution of the gas from the column before the gas is detected by the detector. The apparatus can be adapted for use in an instrument for the elemental analysis of a sample for carbon, hydrogen, nitrogen and sulfur. The invention method includes the steps of introducing a sample in vapor form into a gas chromatography column, passing the sample through the column so as to separate at least one component of interest, passing the component of interest through a conduit to the detector so as to reach the detector after the essentially complete elution of the component of interest from the column.

Abstract: An automatic apparatus for loading and feeding crucibles to and removing crucibles from a combustion furnace in which metals are burned for analyzing them. The apparatus has a part for automatically transporting crucibles to a sample weighing position one by one, a sample weighing device at the sample weighing position, and a supply device for placing the desired quantity of metal to be analyzed into crucibles at the sample weighing position. A storage device for automatically storing crucibles containing samples therein extends from the sample weighing position, and a device takes crucibles out of the storage device one by one and a further device automatically takes the crucibles from said taking out device and introduces them into a combustion furnace and removes the crucibles from the combustion furnace. A device then automatically dumps the crucibles removed from the combustion furnace after the completion of analysis.

Abstract: A new method is disclosed for determining sulfur levels in liquid or solid samples. The method is capable of accurate determination of sulfur content at sub-parts per million levels. The method and apparatus utilize high temperature oxidation of the samples to form sulfur oxides, absorption of the sulfur oxides on copper oxide as copper sulfate, thermal decomposition of the sulfate to convert sulfur present to sulfur dioxide which is evolved and coulometric titration to measure the quantity of evolved sulfur dioxide from which sulfur content of the sample can be calculated.

Abstract: An analytical method for the independent or simultaneous determination of any number of elements selected from the group consisting of nitrogen, carbon, hydrogen and sulfur or chlorine in samples, which comprises passing an oxygen gas through a reaction tube packed with an oxidation catalyst or oxidizing agent having a heating zone of from 800.degree. C. to 1100.degree. C., introducing a sample into said tube to subject it to complete combustion, uniformalizing the gas, dividing the gas into two portions, and introducing one portion in a carrier gas into a copper-reducing tube having a heating zone of from 400.degree. C. to 700.degree. C., determining the resulting nitrogen gas, carbon dioxide gas and steam or acetylene gas on a gas detector, while introducing the second portion in an oxygen gas into an absorption liquor, and determining the resulting sulfate or chlorine ion and, an apparatus useful therefor.

Abstract: A method of geochemical prospecting for buried sulphur mineralization which comprises collecting relatively organic free soil samples, desorbing bound sulphur gases from the soil samples, and analyzing the sulphur gases.