Abstract: There are disclosed a process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient to remove oxygen and/or carbon dioxide that are contained as impurities in the ammonia, and a process for purifying ammonia which comprises bringing crude ammonia into contact with a catalyst comprising manganese oxide as an effective ingredient, and thereafter with a synthetic zeolite having a pore diameter in the range of 4 to 10 Å to remove at least one impurity selected from the group consisting of oxygen, carbon dioxide and moisture that are contained in the crude ammonia. It is made possible by the above process to remove impurities to an extremely low concentration from crude ammonia available on the market for industrial use and crude ammonia from a gallium nitride compound semi- conductor without decomposition of ammonia to generate hydrogen.

Abstract: There are disclosed a process for cleaning ammonia-containing exhaust gas which comprises bringing the exhaust gas into contact with an ammonia decomposition catalyst (e.g. nickel, ruthenium) under heating to decompose most of the ammonia into nitrogen and hydrogen, subsequently bringing the resultant mixed gas into contact with an ammonia adsorbent (e.g. synthetic zeolite) for adsorbing undecomposed ammonia, and then heating regenerating the adsorbent, while bringing reproduced exhaust gas containing the ammonia desorbed from the adsorbent into contact under heating, with the ammonia decomposition catalyst or another ammonia decomposition catalyst; and an apparatus for carrying out the process. It is made possible by the process and apparatus to efficiently and completely clean ammonia-containing exhaust gas exhausted from a semiconductor manufacturing process and the like without generating useless byproduct and dispensing with secondary treatment.

Abstract: The present invention provides a measuring apparatus and method for measuring the quantity of ventilation, whereby the quantity of ventilation correlates to the heating characteristics. [The present invention is also] able to measure the quantity of ventilation of a gas permeable packing material used in heating packets in a short period of time, regardless of the type or pore diameter of the packing material. The present invention provides heating packets displaying stable heating characteristics. In the present invention, one surface of a gas permeable packing material is exposed to the atmosphere, while the opposite surface is scavenged with a carrier gas which does not include oxygen. The present invention measures the oxygen diffusing capacity, [as the diffusion of oxygen] from the atmosphere through the gas permeable packing material, by measuring the concentration of oxygen in the carrier gas after scavenging.

Abstract: A chemical vapor deposition apparatus for forming a semiconductor film, which includes a lateral reaction tube including a susceptor for placing a substrate thereon; a round-shaped heater for heating the substrate; and a gas inlet for introducing a gas containing at least one source gas, the inlet being provided so as to be substantially parallel to the substrate, wherein the heating density of an upstream portion, with respect to the flow of the gas, of the round-shaped heater is higher than that of the remaining portion of the heater. A chemical vapor deposition process employing the chemical vapor deposition apparatus is also disclosed.

Abstract: There are disclosed a process for recovering ammonia which comprises installing a shell and multi-tube adsorber which is equipped with plural adsorption tubes each packed inside with an ammonia adsorbent (e.g. synthetic zeolite) and equipped with a flow mechanism for a heat transfer medium for performing heat exchange through the adsorption tubes, passing an ammonia-containing gas through the adsorption tubes, while cooling the adsorbent with a heat transfer medium (e.g. water) to adsorb the ammonia, and thereafter collecting the adsorbed ammonia through desorption, while heating the adsorbent with a heat transfer medium (e.g. hot water) under reduced pressure; and an apparatus for the above process.

Abstract: An apparatus for vaporizing a liquid material and supplying the material in a gas phase, in which a liquid material for CVD is introduced into a vaporizer at a controlled flow rate, atomized by an ultrasonic atomizing device disposed at the inside or the outside of the vaporizer, heated by a circular flow of a carrier gas and vaporized. When a liquid material for CVD is supplied to a CVD apparatus in the production of semiconductors, the concentration of the material is controlled easily in the vaporization, the concentration of the material in the gas can be changed quickly in response with the change in the flow rate of the material, decomposition of the material does not occur and the operating condition of a CVD apparatus is not restricted.

Abstract: Provided is a heat generating bag for footwear having a comfortable temperature regardless of the state of use, namely, when staying still, walking etc., which is thin and avoids an uncomfortable feeling of the wearer. The heat generating bag for footwear is made by having a heat generating composition powder and hot-melt adhesive powder held in the pores of multiporous vegetable fiber non-woven fabrics, such fabrics being heat compressed on a mold compressor, and the obtained sheet shaped heat generating body being packed in an air-permeable bag. The heat composition is held in the pores of multiporous vegetable fiber non-woven fabric layers which are superposed by the adhesion of water. Such non-woven fabric are compressed on a mold compressor, and the obtained sheet shaped heat generating body is impregnated with water or an inorganic electrolyte and then packed in an air-permeable bag.

Abstract: The present invention provides a warmer in the form of a sheet shaped heat generating body which is obtained using a warming composition that generates heat when in contact with air, in which the warming composition can be easily dispersed and held in a uniform arrangement, and in which the warming composition is prevented from leaking; and provides a method for manufacturing such a sheet. The sheet shaped heat generating body pertaining to the present invention is obtained by supporting a warming composition and a heat-fusible adhesive powder on a nonwoven fabric (a), superposing a nonwoven fabric (b) on the upper surface, heating and pressing the assembly with the aid of a molding press, and impregnating the resulting sheet with water or an aqueous solution of an inorganic electrolyte.

Abstract: A process for preparing a nitride film by a chemical vapor deposition method, which entails reacting a material gas including tert-butyl hydrazene as the main component as the main component of a nitrogen source with a material gas of an organometallic compound, a metal halide or a metal hydride to deposit the nitride film on a substrate.

Abstract: A purified alkoxide from which volatile impurities causing polymerization and degradation of the alkoxide are removed to extremely low concentrations. The purified alkoxide can be obtained by distilling a crude alkoxide and stripping the distilled liquid alkoxide by applying ultrasonic vibration while passing an inert gas through the liquid alkoxide. A high quality thin insulating film excellent in flatness with few defects such as voids can be obtained by using the purified alkoxide of the present invention as a CVD material.

Abstract: Water is adhered to the bottom face of a non-woven fabric having a large number of pores, then a heat generating powder composition is sprayed onto the top face of this fabric to be held in place. Another non-woven fabric is then superposed on the top face of the first non-woven fabric and the two non-woven fabrics are compressed. Water or a solution of electrolytes in water is then sprayed on the fabrics. Thereby, a sheet shaped heat generating body can be provided which uses a heat generating composition which generates heat when contacting air, which prevents concentration of the heat generating composition in one direction, and which is thin, flexible and has good heat generating properties.

Abstract: There is disclosed a process for cleaning a harmful gas which comprises bringing a harmful gas containing at least one member selected from the group consisting of nitrogen fluorides, tungsten fluorides, silicon fluorides, hydrogen fluoride and fluorine, especially nitrogen trifluoride into contact with a cleaning agent comprising stannous oxide as an effective ingredient at a temperature of 200.degree. C. at the lowest. The above process makes it possible to clean the harmful gas in a high performance at a relatively low temperature without by-producing a harmful gas or a gas with a fear of causing environmental pollution.

Abstract: A dust removing apparatus equipped with a back washing mechanism and a dust removing method for removing solid silica fine powder contained in a gas discharged from a semiconductor producing step of a single-wafer processing atmospheric pressure CVD apparatus without causing problems caused by the increase of a pressure loss and by a pressure fluctuation, wherein filter elements each having a ratio of a surface area of a primary side of a filter membrane to an apparent external surface area of the filter element of from 1 to 5 is used, gas jetting nozzle(s) for back washing is formed in the secondary side of the filter element, back washing is not carried out during filtration in the filter element and at or after changing the processing of a wafer in the CVD apparatus, back washing is carried out to blow down the silica fine powder accumulated on the primary side of the filter membrane.

Abstract: There are disclosed a cleaning agent for removing a fluorine-compound gas such as hydrogen fluoride, fluorine, tungsten hexafluoride, silicon tetrafluoride and boron trifluoride which agent comprises a molded article produced by using strontium hydroxide as a principal component, an organic binding agent as a molding agent and the hydroxide of an alkaline earth metal other than strontium as a molding aid; and a process for cleaning a harmful gas which comprises feeding a harmful gas containing a fluorine-compound gas into a column packed inside with the above cleaning agent to remove the fluorine-compound gas; and exhausting a gas substantially free from the fluorine-compound gas. The above cleaning agent is capable of removing the fluorine-compound gas in high efficiency without causing any danger, thereby making itself well suited to the cleaning of the gases exhausted, for example, from semiconductor manufacturing industries.

Abstract: A detecting agent for detecting at least one member selected from the group consisting of halogen gases and acidic gases which is contained in a gas, wherein the detecting agent comprises a discoloring component which comprises a hydroxide of a transition metal and Congo Red. Halogen gases and acidic gases which are contained in hydrogen, nitrogen, argon, or helium can be detected under a dry condition with a high sensitivity in accordance with the present invention.

Abstract: A process for cleaning a harmful gas which comprises bringing a harmful gas containing a halogen gas and/or a halogen compound gas such as hydrogen fluoride, hydrogen chloride, tungsten hexafluoride, silicon tetrafluoride and boron trifluoride into contact with a cleaning agent comprising metal oxides composed principally of copper (II) oxide and manganese (IV) oxide that are spreadingly and adhesively incorporated with sodium formate so as to remove a harmful component from the harmful gas. According to the cleaning process of the present invention, it is possible to remove harmful components from the harmful gas in extremely high efficiency at ordinary temperature, dispensing with heating or cooling irrespective of the concentration of the harmful components. The cleaning capacity of the cleaning agent is favorably maintained without deterioration even when the harmful gas is in a dry state.

Abstract: A cleaning agent for removing acidic gases which are harmful materials from a harmful gas containing such acidic gases, and a cleaning method using the cleaning agent are disclosed. The cleaning agent comprises a molded product of a composition comprising strontium hydroxide and an iron oxide, and the harmful gas is passed through a cleaning column packed with the cleaning agent to contact the harmful gas with the cleaning agent, thereby removing the acidic gases from the harmful gas.

Abstract: A detecting agent for hydride gases (arsine, phosphine, silane, diborane, selenium hydride etc.) which comprises at least one member selected from molybdic acid, a salt thereof, a molybdenum-containing acid (molybdophosphoric acid, etc.) and a salt thereof, and optionally a cupric salt each as a discoloring component being supported on an inorganic carrier (silica, alumina, silica-alumina, zirconia, etc.). The above detecting agent can detect the above hydride gases contained in the exhaust gas discharged from a semiconductor manufacturing process, with high accuracy, selectivity and sensitivity at a high discoloring rate without being influenced by other gases such as hydrogen gas.

Abstract: There is disclosed a process for cleaning a harmful gas which comprises bringing a gas containing a basic gas as a harmful component such as ammonia and amines into contact with a cleaning agent comprising a cupric salt supported on an inorganic carrier composed of an metallic oxide such as silica and alumina or a metallic oxide mixture of cupric oxide and manganese dioxide to remove the harmful component from the gas containing a basic gas.According to the above process, it is made possible to effectively remove a basic gas such as ammonia and trimethylamine contained in the exhaust gas from semiconductor production process; and a harmful basic gas contained in dilution gas such as air or nitrogen which dilutes the harmful gas suddenly leaked in emergency from a gas bomb filled inside with the harmful gas. Moreover, the process enables to prevent the occurrence of fire even in the coexistence of other gas such as silane, while maintaining excellent effect on the removal of the harmful gas.

Abstract: A cleaning method for an exhaust gas containing ammonia, silanes, and organometallic compounds exhausted from a nitride film production step, etc., for producing compound semiconductors.After removing the silanes and the organometallic compounds from the exhaust gas by contacting the exhaust gas with a cleaning agent comprising soda lime having provided thereon a copper(II) salt, the exhaust gas is contacted with an ammonia decomposition catalyst to decompose ammonia into hydrogen and nitrogen, and undecomposed ammonia in the remaining exhaust gas is then removed by a cleaning agent comprising an inorganic carrier having provided thereon a copper(II) salt, or an active carbon having provided thereon copper sulfate.