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Higher Hydrocarbon Production through Oxidative Coupling of Methane Combined with Hydrogenation of Carbon Oxides 下载免费PDF全文
In the production of higher hydrocarbons, combining oxidative coupling of methane (OCM) with hydrogenation of the formed carbon oxides in a separate reactor provides an alternative to the currently applied methane conversion to syngas followed by Fischer‐Tropsch synthesis. The effects of CH4:O2 feed ratio in the OCM reactor and partial pressures of H2 or/and H2O in the hydrogenation reactor were analyzed to maximize production of C2+ hydrocarbons and reduce COx formation. The highest C2+ yield was achieved with low CH4:O2 feed ratio for OCM and removal of the formed water before entering the hydrogenation reactor. 相似文献
54.
Monica Badila Christoph Jocham Wenbiao Zhang Thomas Schmidt Günter Wuzella Uwe Müller Andreas Kandelbauer 《Progress in Organic Coatings》2014
The powder coating of veneered particle boards by the sequence electrostatic powder application – powder curing via hot pressing is studied in order to create high gloss surfaces. To obtain an appealing aspect, veneer sheets were glued by heat and pressure on top of particle boards and the resulting surfaces were used as carrier substrates for powder coat finishing. Prior to the powder coating, the veneered particle board surfaces were pre-treated by sanding to obtain good uniformity and the boards were stored in a climate chamber at controlled temperature and humidity conditions to adjust an appropriate electrical surface resistance. Characterization of surface texture was done by 3D microscopy. The surface electrical resistance was measured for the six veneers before and after their application on the particle board surface. A transparent powder top-coat was applied electrostatically onto the veneered particle board surface. Curing of the powder was done using a heated press at 130 °C for 8 min and a smooth, glossy coating was obtained on the veneered surfaces. By applying different amounts of powder the coating thickness could be varied and the optimum amount of powder was determined for each veneer type. 相似文献
55.
Hans-Joachim Nees Harald Keller Thomas Facklam Albert Herrmann Jochen Welsch Uwe Bergstrßer Heinrich Heydt Manfred Regitz 《Advanced Synthesis \u0026amp; Catalysis》1993,335(7):589-598
Diazo Compounds. 72. Diazoalkylphosphanes – Synthesis by Electrophilic Diazoalkane Substitution and Oxidative Addition Reactions at Phosphorus Electrophilic diazoalkane substitution of the diazomethyl compounds 1a,b with the chloro phosphanes 2a-o in the presence of lithium diethylamide yields the diazoalkyl phosphanes 3a-z . Oxidative addition of oxygen, sulfur and selenium at phosphorus leads into the series of oxo, thioxo and selenoxo phosphanes having diazoalkyl substituents ( 4a-d, 5a-m and 7a-d ). The silyl group of 5n,o is cleaved by chromatography on aluminium oxide to yield the (diazomethyl)phosphane sulfides 6a,b . 相似文献
56.
Investigation on Mesityldimethylhalosilanes as Protectiv Reagents for Alcohols The use of mesityldimethylhalosilanes as protecting reagents for steroid alcohols was investigated. The resistance of the obtained silyl ethers was tested in various media. The reaction pathway of the acidic hydrolyses of the silyl ethers is explained. 相似文献
57.
Werner-Michael Kulicke Uwe Kaiser Dieter Schwengers Rolf Lemmes 《Starch - St?rke》1991,43(10):392-396
Solutions of hydroxyethyl starch are used as a blood plasma substitute. If their physiological efficiency is to be optimized, they need to be accurately characterized in terms of their molecular weight and its distribution. The absolute determination of molecular weight and molecular weight distribution by means of light scattering require a knowledge of the refractive index increment. Although numerous investigations of the refractive index increment of hydroxyethyl starch have already been published, the results vary significantly due to the use of different samples and the choice of different measuring parameters. There was therefore an urgent need to examine the extent to which the refractive index increment depends on molecular parameters, the experimental method used and the type of processing. Here it was found that different sample preparations result in different contents of solid matter, so that an exact determination of the quantity is required. Hydroxyethyl starches in the molecular weight range of about Mw = 200.000 g/mol and varying degrees of substitution between DS 0.38 and 0.50 which are regarded as optimal for clinical use give a refractive index increment of dn/dc633nm = 0.146 = 0.005 cm3/g (solvent: H2O/0.02% NaN3; T = 25°C). 相似文献
58.
E. Vilsmaier Markus Grosse Wolf-Rüdiger Schlag Gunther Milch Uwe Bergstrßer Andreas Ritter von Onciul 《Advanced Synthesis \u0026amp; Catalysis》1996,338(1):479-484
6-Piperidino-3-azabicyclo[3.1.0]hexane-6-carboxamide diastereomers 1a and 2a represent conformationally rigid analogues of 3a which is a building block in some pharmaceutical compounds. A new access to these compounds 1a and 2a was found via the cleavage of bicyclic N,N-acetal 6 with hydrocyanic acid as the stereodetermining step. Reaction of derivatives 1a and 2a with bromodiphenyl-butyronitrile 14 gave cyclopiritramide isomers 1c and 2c , respectively. Qualitative preliminary investigations showed different affinities of 1c and 2c to the opiate-μ receptor. These results were discussed on the basis of an X-ray structural analysis of cyclopiritramide isomer 2c . 1-Benzylcyclopiperidine derivatives 1d and 2d were used as model systems for studying the conformation of cyclopiritramide isomer 1c and 2c , respectively. 相似文献
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Mohamed M. Soumanou Uwe T. Bornscheuer Rolf D. Schmid 《Journal of the American Oil Chemists' Society》1998,75(6):703-710
Structured triacylglycerides with medium-chain fatty acids (caprylic acid) in sn1- and sn3-positions and a long-chain unsaturated fatty acid (oleic or linoleic acid) in the sn2-position of glycerol (MLM) were synthesized by lipase catalysis in a two-step process. First, pure 2-monoacylglycerides
(2-MG) were synthesized by alcoholysis of triacylglycerides (triolein, trilinolein, or peanut oil) in organic solvents with
1,3-regiospecific lipases (from Rhizomucor miehei, Rhizopus delemar, and Rhizopus javanicus). The 2-MG were purified by crystallization and obtained in up to 71.8% yield. These 2-MG were esterified in a second reaction
with caprylic acid in n-hexane to form almost pure MLM. For 2-MG obtained from peanut oil, the final product contained more than 90% caprylic acid
in the sn1- and sn3-positions, whereas the sn2-position was composed of 98.5% unsaturated long-chain fatty acids. Reaction conditions for both steps were optimized with
respect to source and immobilization of lipase, water activity, and solvent. 相似文献