摘要:
A solid state catalyst consists essentially of hydrated niobium oxide containing a phosphoric acid on its surface in an amount sufficient to increase surface acidity, to inhibit crystallization of the niobium oxide and to retard loss in catalytic activity following exposure to high temperature. The catalyst can be prepared by treating hydrated niobium oxide (Nb.sub.2 O.sub.5.xH.sub.2 O) or an anhydride thereof with a phosphoric acid. The catalyst is useful in the hydration of ethylene to form ethanol.
摘要翻译:固态催化剂基本上由含有磷酸的水合铌氧化物组成,其表面的量足以增加表面酸度,抑制氧化铌的结晶,并延缓暴露于高温后催化活性的损失。 催化剂可以通过用磷酸处理水合氧化铌(Nb 2 O 5·xH 2 O)或其酸酐来制备。 该催化剂可用于乙烯水合形成乙醇。
摘要:
Para-hydroxybenzoic acid is prepared by reacting an alkali metal salt of phenol except the lithium and sodium salts with carbon dioxide in the presence of at least one compound selected from compounds of the following formulae (I) and (II): ##STR1## In formulae (I) and (II), M is an alkali metal except lithium and sodium; R is any substituent except an aliphatic hydroxy group having up to 4 carbon atoms, an aliphatic mercapto group having up to 4 carbon atoms, a substituent having at least one of them as its structural unit, and a hydrogen atom; R' is any substituent except an aliphatic hydroxy group having up to 4 carbon atoms, an aliphatic mercapto group having up to 4 carbon atoms, and a substituent having at least one of them as its structural unit; in formula (I) n is an integer of 1 to 5, and R groups may be the same or different when n is more than one; in formula (II) m is an integer of 1 to 5 and l is an integer of 0 to 4, and M alkali metals may be the same or different when m is one or more, and R' groups may be the same or different when l is more than one. The reaction may be carried out in the presence or absence of reaction medium.
摘要:
The improved process for preparing para-hydroxybenzoic acid comprises reacting potassium phenol with carbon dioxide in an inert reaction medium or without using a reaction medium in the presence of at least one compound selected from the group consisting of the compounds represented by the following general formula I or II: ##STR1## at a reaction temperature of 230.degree.-450.degree. C. and at a carbon dioxide pressure ranging from atmospheric pressure to 6 kg/cm.sup.2 (G). The process may comprise two stages and the first-stage reaction described above is followed by the second stage in which the reaction is further continued with the pressure of carbon dioxide in the system being reduced and/or the reaction temperature being elevated within the range specified above.Also, phenol may be used as the starting material instead of potassium phenolate.
摘要:
Apparatus and method for generating screened halftone images, which includes means for assuming an area of halftone dots with desired periodicity and tone reproducibility, subdividing the area into minute cells and setting address values (X, Y) for each of the minute cells, computing out a threshold value of density for each of said cells as a function f (X, Y) of the relevant address values (X, Y), and using the computed value as threshold value of density for the cell, means for obtaining a density-related video signal of the portion of the original corresponding to each of said cells by scanning the original, and means for producing halftone dot signals by comparing the video signals and the threshold value of density with each other.
摘要:
A DHA-containing food material includes a marine micro algae containing docosahexaenoic acid (DHA). A method of manufacturing the DHA-containing food material has the steps of culturing the marine micro algae containing DHA, separating bodies of the algae, water-washing, disinfecting and drying the bodies of the algae. A DHA-containing food including the marine micro algae containing the DHA can be directly added to a food. A method of manufacturing the DHA-containing food material may include the steps of kneading the marine micro algae containing the DHA with a food material, and heating the kneaded material.