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A Novel Technology for Natural Gas Conversion by Means of Integrated Oxidative Coupling and Dry Reforming of Methane 下载免费PDF全文
Dr. Joris W. Thybaut Prof. Guy B. Marin Dr. Claude Mirodatos Dr. Yves Schuurman Dr. Andre C. van Veen Prof. Vladislav A. Sadykov Dr. Helmut Pennemann Dr. Rainer Bellinghausen Prof. Leslaw Mleczko 《化学,工程师,技术》2014,86(11):1855-1870
A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO2, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming. 相似文献
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Gerhard Heise Andreas Brner Marcel Dickmann Marina Englmaier Andreas Heiss Matthias Kemnitzer Jan Konrad Regina Moser Jrg Palm Helmut Vogt Heinz P. Huber 《Progress in Photovoltaics: Research and Applications》2015,23(10):1291-1304
In this paper, we present the selective structuring of all three patterns (P1, P2 and P3) of a monolithic interconnection of CIS (Cu(In,Ga)(S,Se)2) thin film solar cells by picosecond laser pulses at a wavelength of 1064 nm. We show results for single pulse ablation threshold values and line scribing of molybdenum films on glass (P1), CIS on molybdenum (P2) and zinc oxide on CIS (P3). The purposes of these processes are the p‐type isolation (P1), cell interconnect (P2) and n‐type isolation (P3), which are required for complete cell architecture. The half micron thick molybdenum back electrode can be structured with a process speed of more than 15 m/s at about 15 W average power without detectable residues and damage by direct induced laser ablation from the back side (P1). The CIS layer can be structured selectively down to the molybdenum at process speeds up to 1 m/s at about 15 W average power, due to the precision of direct laser ablation in the ultrashort pulse regime (P2). The ZnO front electrode layer is separated by clean trenches with straight side walls at process speeds of up to 15 m/s at about 10 W average power, as a result of indirect induced laser ablation (P3). A validation of functionality of all processes is demonstrated on CIS solar cell modules (30 × 30 cm2). By replacing one state‐of‐the‐art process by a picosecond laser process at a time, solar efficiencies could be increased for P1 and P2 and stayed on a similar level for P3. After an optimization of the patterning processes in the R&D pilot line of AVANCIS, we achieved a new record efficiency for an all‐laser‐patterned CIS solar module: 14.7% as best value for the aperture area efficiency of a 30 × 30 cm2 sized CIS module was reached. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Recent developments in the formulation of detergents have been driven by a strong consumer demand for natural and biodegradable products. Detergent manufacturers responded to this demand with corresponding products and advertising slogans such as “fully biodegradable”, “natural” or even “double natural” to oust their competitors. In a detergent formulation, starch- derived products can in principle be used for the following purposes: as the hydrophilic head group in surfactants, as the starting material for (poly)carboxylate co-builders and as the backbone of bleaching activators. Non-ionic classical surfactants can be replaced by alkylpolyglucosides (APGs), a class of products completely based on renewable resources such as glucose and fatty alcohols derived from natural fatty acids. Sodium tripolyphosphate (STPP), the product responsible for the eutrophication of surface waters, can be substituted by a combination of an inorganic zeolite and highly oxidised starch (dicarboxylic starch) or by citrate. Acetylated polyols derived from hydrogenated carbohydrates such as sorbitol can take over the function of the petrochemically-based tetraacetyl ethylene diamine (TAED) used as activator to allow perborate bleaching at lower washing temperatures. 相似文献
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比较了PET和PA纤维的原液染色与纺织品染色.详细描述了原液染色和纺织品染色的优缺点.讨论了汽车用染色物品的着色和色彩协调.介绍了Clariant产品(瑞士)公司开发的"可染色的"颜料. 相似文献
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Unambiguous Synthesis of 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine — Further Comments on the “(N C)-Rearrangement” of (2-Alkoxycarbonyl-vinyl-amino)pyrazols 4,7-Dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine 1a is synthesized by decarboxylation of 1-benzyl-5-carboxy-4-hydroxy-pyrazolo[3,4-b]pyridine 4b and debenzylation of 1-benzyl-4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridine 1b with sodium in liquid ammonia. The product from 3-amino-pyrazol and methyl propiolate, formerly described as 1a , obviously is the 6-oxo isomer 2a . Use of the parameter δ13(CO) for the structural assignment of pyrazolo[3,4-b]pyridones is only permitted, if in the corresponding media mainly the oxo-tautomer is existing. It is again demonstrated that DMSO is often an insufficient medium. Debenzylation of 1b and similar compounds with SeO2 is only possible, if the α-position of CO is blocked by a substituent. Otherwise diselenids of type 6 are formed. This obviously is a general reaction of cyclic lactames. The cyclisation of (2-alkoxycarbonyl-vinyl-amino)pyrazols 7 in acidic media, and with catalytical amounts of the corresponding amino-pyrazols gives 6,7-dihydro-6-oxo-pyrazolo[3,4-b]pyridines 2 via amino 4-(2-alkoxycarbonyl-vinyl)pyrazols 8 , i.e. via products of an “(N C)-rearrangement”, while by thermal cyclisation of 7 4,7-dihydro-4-oxo-pyrazolo[3,4-b]pyridines 1 are formed. 相似文献
80.
Mayrhofer S Domig KJ Amtmann E Van Hoek AH Petersson A Mair C Mayer HK Kneifel W 《Journal of food protection》2007,70(1):119-124
The widespread use of antimicrobial substances has led to resistant populations of microorganisms in several ecosystems. In animal husbandry, the application of antibiotics has contributed to resistance development in pathogenic and commensal bacteria. These strains or their resistance genes can be spread along several ecological routes, including the food chain. Antibiotic resistance is important in terms of the safety of industrial strains, such as probiotics for food and feed. Bifidobacterium thermophilum and Bifidobacterium pseudolongum are known to comprise the major part of the bifidobacterial microbiota in the gut and feces of cattle and pigs. In this study, the antimicrobial susceptibility in bifidobacterial isolates of these species was investigated. Isolates from the beef and pork production chain were identified and typed to strain level, and the antimicrobial susceptibility level was tested to a set of antibiotics. Isolates with low susceptibility levels were screened by PCR for already described resistance genes. Strains atypically resistant to clindamycin, erythromycin, and tetracycline were determined. The resistance genes tet(O), tet(W), and erm(X) were detected in the bifidobacterial species that were examined. 相似文献