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排序方式: 共有182条查询结果,搜索用时 15 毫秒
21.
F Loi G Battista GM Malentacchi C Paradiso A Pompella M Rubegni A Federico 《Canadian Metallurgical Quarterly》1981,2(3):283-290
Three members of a family were found be suffering from lead poisoning of nonindustrial origin, the causative agent being the home-produced wine left to ferment in a glazed earthenware vat. The clinical and neurophysiological features are discussed in the light of similar cases in the literature. Correct diagnosis and early treatment of nonindustrial lead polyneuropathy are often extremely difficult because of the elusive nature of the exposure. 相似文献
22.
Colloidal microcrystalline cellulose, introduced in 1961, now is a successful commercial product with growing world-wide markets. This paper describes some major findings of our continuing research to convert fibrous or fiber-forming polymer systems into new colloidal microcrystalline physical states without going through a homogeneous molecular solution phase. Several novel microcrystalline colloidal products from the following natural and/or synthetic polymeric raw materials are described and compared for the first time: cellulose, amylose, collagen, nylon, and chrysotile mineral silicates. Many previously unpublished electron micrographs are presented. These products demonstrate a new and growing field of colloidal microcrystalline polymer science. They open up increasing opportunities for new polymer products based on the original concept, namely, the unhinging of polymer microcrystals from their natural or synthetic network and then by appropriate mechanical energy, releasing them as discrete, submicron colloidal polymer microcrystals dispersed in various liquid media to form unique gel systems, or reaggregated in the dry state to form porous colloidal particles. 相似文献
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24.
José G. García Clúa Hernán De Battista Ricardo J. Mantz 《International Journal of Hydrogen Energy》2010
This paper deals with the control of a H2 production system supplied by wind power and assisted by the grid. The system architecture consists of a pitch-controlled wind turbine coupled through a diode rectifier to an alkaline electrolyzer, which in turn is connected to the electric grid through a fully-controlled bidirectional electronic converter. A control strategy for the electronic converter is proposed to regulate the electrolyzer current at its rated value. Thus, H2 production efficiency is optimized despite wind power and temperature variability. Control design is based on sliding mode techniques, which are particularly appropriate to control fast switching devices and exhibit strong robustness properties. Additionally, in high wind speeds, a pitch control loop is activated to limit the wind power capture below admissible values. 相似文献
25.
Biomass cofiring at Seward Station 总被引:3,自引:0,他引:3
Sithe Energies, under a cooperative agreement with EPRI, the US Department of Energy, the Biomass Interest Group (BIG) and the Upgraded Coal Interest Group (UCIG), has developed a demonstration of cofiring biomass with pulverized coal at the Seward Generating Station on Boiler #12. This demonstration, constructed and tested by Foster Wheeler Development Corporation (FWDC) included construction of a facility to receive, screen, store and transport sawdust into a front-fired pulverized coal boiler. This facility has several distinctive features including the sawdust receiving system, the silo storage for processed biomass, and the injection system using the centerpipe of the coal burners. The biomass is prepared separately and transported separately from the coal. The wood waste is then injected into the center of the coal flame and burned there for optimum biofuel performance.
This demonstration, involving an extended period of cofiring testing, is based upon successful parametric tests conducted in December, 1996 and July, 1997. These tests documented the impact of cofiring, in the short term, on capacity, efficiency and emissions. Those results are now being evaluated over a long-term period. Additionally, operational and maintenance issues are being addressed with this demonstration and modifications have been made to improve the handling of the fuel. This paper describes the cofiring system, and reviews progress to date with the combustion tests. 相似文献
26.
27.
Marica Consolini Michela Sega Chiara Zanetti Marina Fusi Roberto Chignola Marco De Carli Corrado Rizzi Gianni Zoccatelli 《Food Analytical Methods》2012,5(2):234-243
Wheat α-amylase inhibitors (α-AIs) are known anti-nutritional factors, respiratory allergens, and they can sporadically cause
food allergy. α-AIs are therefore expected to reach the enteric mucosae in an immunologically active form, but information
on their stability to gastric digestion is not available. Resistance to pepsinolysis is nonetheless a key factor for any food
allergen. We therefore investigated whether α-AIs could resist pepsin digestion in simulated gastric fluids (SGF) and in emulsified
SGF, the latter simulating more realistically the multi-phase nature of stomach bolus. Since α-AIs comprise a huge family
of proteins, we investigated 0.19 α-AI as a prominent member. The digestion patterns were analyzed by immunoblotting using
anti-0.19 polyclonal antibodies and sera from wheat allergic patients sensitized to 0.19 α-AI. The results show that the immune
epitopes of α-AI are detectable up to 120 min of digestion in emulsifying conditions. Intra-molecular disulfide bonds and,
in particular, emulsification were found to be crucial factors for protein stability. The results show that 0.19 α-AI must
be considered a potential food allergen. 相似文献
28.
Phenol content,antioxidant activity and metal composition of Croatian wines deriving from organically and conventionally grown grapes 总被引:2,自引:0,他引:2
Ivana Vinković Vrček Mirza Bojić Irena Žuntar Gordana Mendaš Marica Medić-Šarić 《Food chemistry》2011
The present study was performed to evaluate the antioxidant capacity, the polyphenol and metal content of conventionally and organically produced wines, which underwent similar winemaking processes. The wine grapes were grown under well-defined organic and conventional conditions from the two different wine-growing sub-regions of Croatia, Prigorje and Southern Dalmatia. The values of antioxidant activity, as evaluated by two free radical methods, ABTS and DPPH, was found systematically higher in organic wines compared to conventional ones. In a reversed phase HPLC analysis, used in order to characterise the phenol fraction of wines, higher concentrations of chlorogenic acid, ferulic acid, catechin, trans-resveratrol, all studied hydroxybenzoic acids and flavonols were found in the organically produced wines. No apparent trend was found in the metal contents of the wines, but ICP-MS analysis confirmed that both wine productions, organic and conventional, were well within the toxicological safety limits. 相似文献
29.
Emanuela Fontana Jeanet Hoeberechts Silvana Nicola Victor Cros Giovanni Battista Palmegiano Pier Giorgio Peiretti 《Journal of the science of food and agriculture》2006,86(14):2417-2424
Purslane is an excellent source of omega‐3 fatty acids, amino acids and vitamins. The aim of this research was to study the effect of different nitrogen levels and NO3−‐N/NH4+‐N ratios in the nutrient solution on the yield and on the oxalic acid content and fatty acid profile in purslane grown in a soilless culture system. Two experiments were carried out to test different levels of nitrogen: (1) 8–12–16 mmol L−1 and (2) 0–12–24–36 mmol L−1. A third experiment was carried out maintaining the N level fixed (12 mmol L−1) but varying the NO3−‐N/NH4+‐N ratio: 60:40, 40:60, 0:100. The results indicated that plants grew with increasing nitrogen level up to 36 mmol L−1. Nitrogen supplied in both NO3− and NH4+ forms produced bigger plants than N supplied in NH4+ form only. Nitrogen did not significantly influence the polyunsaturated fatty acid content in the canopy. Significant trends were found for α‐linolenic acid (LNA; 18:3 n‐3) and linoleic acid (LA; 18:2 n‐6), indicating a favorable accumulation of omega‐3 fatty acids with increasing N; palmitic acid decreased by increasing N and by switching the NO3−/NH4+ ratio towards the NH4+ level in the nutrient solution, but using 0:100 NO3−/NH4+, decreased plant quality. Increasing N lowered oxalic acid production and palmitic acid content, enhancing purslane nutritional quality. Keeping a high N level in the nutrient solution with a 40:60 NO3−/NH4+ ratio would give the best results in terms of yield, oxalic acid concentration and fatty acid profile. Copyright © 2006 Society of Chemical Industry 相似文献
30.
Marica Castigliano 《Planning Perspectives》2018,33(2):289-292
The RSA Research Network on Regional Economic and Policy History (ReHi) aims to investigate the role of the historic perspective on regional studies through a series of events. During the inaugural two-day workshop, held in London in April 2017, the participants highlighted historical methodologies and approaches that establish a common thread in the various regional disciplines. They defined interdisciplinary connections that need to be addressed to overcome the discontinuous dialogue among researchers of regional studies and history. The research papers that were presented at the conference focused on improving methodologies, analysing economic strategies, developing techniques, and understanding policy development. The workshop aimed at establishing the foundation for a common research framework to improve the scientific debate and provide impact on regional policy regulations. 相似文献