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91.
Tugrul U. Daim Donggyu Lim Fredy A. Gomez Justus Schwarz Stevan Jovanovic 《国际可持续能源杂志》2014,33(1):1-15
The transition from traditional energy sources to renewable has gained popularity and acceptance in recent years. This has been driven mainly by the current level of pollution, global warming, decommission of old nuclear power plants and the increasing cost of conventional energy sources. Nevertheless, one of the many steps to overcome is the seasonality or intermittency of renewable energy sources such as wind power. In recent years, new technologies have come up to address this problem, so the energy can be stored for future purposes. This paper analyses these energy storage alternatives for a specific case in the Columbia River Gorge for wind power. A hierarchical decision model is developed with criteria including political, social, environmental, technical and economical. The main conclusions highlight that the economical and technical criteria are among the most important ones for decision-makers. 相似文献
92.
93.
Karin Schwarz Hedda Ernst Waldemar Ternes 《Journal of the science of food and agriculture》1996,70(2):217-223
The non-polar fraction of thyme was examined for the occurrence of phenolic components and their antioxidative activity. In addition to carvacrol ( II ) and thymol ( III ), p -cymene-2,3-diol (I ; 2,3-dihydroxy-4-isopropyl-1-methylbenzene) was isolated for the first time from thyme. The structure of I was elucidated using 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectrometry. Antioxidative activity was investigated with the Rancimat method (100°C) and the Schaal test (60°C). Compound I exhibited the strongest antioxidative activity which was greater than that of α-tocopherol and butylated hydroxyanisole. Five thyme species were analysed by means of HPLC with electrochemical detection for the concentration of compounds I – III . The highest amounts of I – III were found in Thymus vulgaris L. 相似文献
94.
H. Schick H.-P. Welzel S. Schwarz G. Truckenbrodt 《Advanced Synthesis \u0026amp; Catalysis》1982,324(4):550-556
Prostaglandins and Prostaglandin Intermediates. Oxidative Cleavage of Olefins by Ozonization and Oxidation in the Solvent System Acetone/tert. Butanol – a Method for Preparation of Substituted Cyclopentyl Acetic Acids Oxidative cleavage of olefinic double bonds by ozonization in acetone in the presence of tert. butanol followed by oxidation with JONES ' reagent in the same solvent system gives carboxylic acids and/or ketones in good yields. Acetic acid or water can be used instead of tert. butanol with the same success. This “one-pot” procedure was developed in connection with the synthesis of intermediates for the preparation of 8-methyl-prostaglandin C2. 相似文献
95.
96.
Yu-Jie Fu Wei Liu Yuan-Gang Zu Xiao-Guang Shi Zhi-Guo Liu Günter Schwarz Thomas Efferth 《Food chemistry》2009
The hard sporoderm of Ganoderma lucidum spores prevents the release of bioactive components such as polysaccharides which have significant anti-tumour activity. In the present study, supercritical carbon dioxide (SC–CO2) was used for the sporoderm breaking of G. lucidum spores, and polysaccharides were subsequently extracted and determined for evaluating the performances of SC–CO2. The operating parameters were optimized by orthogonal array design (OAD), and the morphological status of sporoderm was observed by scanning electron microscope (SEM). The optimum operating conditions for SC–CO2 breaking of sporoderm were as follows: pressure 35 MPa, temperature 25 °C, time 4 h, and CO2 flow rate 10 kg/h. After SC–CO2 processing, the extraction yield of polysaccharides reached 2.98%, which was 3-fold to that of the intact ones (0.94%). This method is fast, efficient and advanced enough to break the hard sporoderm of G. lucidum, which may provide a scientific reference for the large-scale processing of spores in the pharmaceutical and food industries. 相似文献
97.
The production of aluminium of primary quality from scrap by electrorefining may become an option of strategic importance. Two important requirements are: (i) substantial energy savings compared to electrowinning, and (ii) easy recycling of alloying elements and molten electrolyte without ecological hazards. The use of molten chloride instead of fluoride electrolytes is preferred as emissions are low, purification of contaminated salts in aqueous solution is easy and oxide ceramic materials for cells and diaphragms can be used. The measurement of formal potentials of most important alloying elements shows that only manganese should be expected to cause trouble in electrorefining of aluminium scrap from alkali chloride melts. Preparative batch refining experiments show that all these alloying metals can be easily separated; manganese is very likely because its activity in aluminium is decreased by alloying or compound formation in aluminium. Results with cells divided by alumina diaphragms show that energy consumptions can be kept below 5 kWh (kg Al)–1. 相似文献
98.
Fritz Theil Hans Schick Peter Nedkov Monika Bhme Barbara Hfner Sigfrid Schwarz 《Advanced Synthesis \u0026amp; Catalysis》1988,330(6):893-899
Subtilisin DY as well as alkaline protease from Bacillus licheniformis 41 p catalyze the hydrolysis of (1SR, 5RS, 6RS, 7RS)-7-acetoxy-6-acetoxymethyl-2-oxabicyclo[3.3.0]octan-3-one ( rac-1 ) with practically useful enantio- and regioselectivity. Under the hitherto found optimal conditions (1S, 5R, 6R, 7R)-7-hydroxy-6-hydroxymethyl-2-oxabicyclo[3.3.0]octan-3-one ( 4 ), an important intermediate in prostaglandin syntheses, could be prepared in a yield of 16% with an enantiomeric excess of 99%. The enantiomer ( ent-4 ) was obtained with the same enantiomeric excess in 20% yield. The chemical yields are related to the racemic starting material rac-1 . 相似文献
99.
100.
H. Schick H.-P. Welzel S. Schwarz G. Truckenbrodt 《Advanced Synthesis \u0026amp; Catalysis》1985,327(1):91-95
A convenient method to convert homoallyl or homopropargyl ketones or alcohols into 4-oxo carboxylic acids or γ-lactones is the oxidative cleavage of the multiple bond with potassium permanganate in diluted sulfuric acid. This is exemplified by the preparation of intermediates for the synthesis of 8-methylprostaglandin C2. The oxidation of the allylic compounds with permanganate is compared with the oxidative cleavage by ozone/hydrogen peroxide, ozone/chromic acid or sodium periodate/potassium permanganate. 相似文献