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101.
电力行业低碳化的关键要素分析及其对电源规划的影响 总被引:16,自引:8,他引:16
在电力系统中实现CO2的有效减排,是当前电力行业所面临的突出问题,而电源规划则将在其中发挥着至关重要的作用。文中分析了面向低碳目标的电源规划模式,在揭示各类低碳要素对传统电源规划模式的影响机制与作用原理的基础上,对实施低碳电源规划的关键技术进行了深入的研究;并分析了在不同的低碳要素场景下,中国电力行业实施低碳化发展的规划前景与碳排放特性,进而讨论了各类低碳要素的应用在实施CO2减排中的作用与潜力。文中的结果为中国电力行业的CO2减排工作提供了有益的参考。 相似文献
102.
Synthesis of binary copper chalcogenides by mechanical alloying 总被引:2,自引:0,他引:2
Copper sulfides (tetragonal Cu1.92S-Cu1.99S, rhombohedral Cu1.71S-Cu1.89S, CuS), selenides (β Cu2 − xSe, Cu3Se2, γ CuSe, CuSe2), and tellurides (Cu2 − xTe, Cu3Te2) were prepared from mixtures of the elements by mechanical alloying (MA), using a high-energy ball mill. The compounds were obtained by 60–120 min of MA. It is notable that two metastable high-pressure phases were obtained by MA: tetragonal Cu2 − xS and pyrite-type CuSe2. The tetragonal phase gradually transformed to the stable phase of djurleite when kept at room temperature. Cu1.71S-Cu1.89S also formed a metastable rhombohedral phase. 相似文献
103.
This paper presents an efficient computational algorithm for selecting the optimal generation mix considering CO2 emissions. To demonstrate the effectiveness and feasibility of the proposed method, a fundamental study of the evaluation of the optimal generation mix for controlling CO2 emissions is indicated. Furthermore, by using a parametric analysis which considers load characteristics as parameters, a general trend for the optimal generation mix which is affected by controlling CO2 can be derived. The proposed method is based on an optimization method known as simulated annealing. In the method, solutions in a generation mix problem are equivalent to state of a physical system, and the cost of a solution is equivalent to the energy of a state. The proposed method can easily accommodate not only CO2 emissions but also many practical constraints of generation expansion planning, such as integer solutions of unit capacities, condition of existing units, and so on. Case studies with various annual load patterns (combinations of annual load factors and the shapes of annual load duration curve) are presented and discussed. Consequently, a general trend for selecting generation technologies that should be added to a power system is derived, i.e., a useful guideline for studying generation expansion planning under controlling CO2 emissions can be provided. 相似文献
104.
105.
A novel bacterial rhodopsin was identified in Haloarcula japonica strain TR-1. The gene encoding the bacterial rhodopsin was cloned and sequenced. The structural gene consisted of an open reading frame of 750 nucleotides encoding 250 amino acids. The deduced amino acid sequence of the Ha. japonica bacterial rhodopsin showed the highest homology to those of cruxrhodopsins. 相似文献
106.
Significance of attached cyanobacteria relevant to the occurrence of musty odor in Lake Kasumigaura 总被引:8,自引:0,他引:8
Norio Sugiura Norio Iwami Yuhei Inamori Osamu Nishimura Ryuichi Sudo 《Water research》1998,32(12):3549-3554
The microorganisms and compounds causing musty odor in the second largest lake in Japan, Lake Kasumigaura, where the water is used for drinking, fisheries and agricultural purposes, were examined during the severe occurrence of musty odor in 1989 and 1990. This study was undertaken to determine the microorganisms and their metabolites responsible for the musty odor. Phormidium tenue, which has been reported to be the main contributor of the odor in Lake Kasumigaura, was isolated. Furthermore, four monoxenic strains of the odor producing attached cyanobacteria, Phormidium viscosum, Lyngbya allorgei, Oscillatoria splendida and Phormidium uncinatum, were isolated from submerged rocks and sediments in the lake. All of the four attached strains produced only geosmin, which was confirmed by gas chromatograph/mass spectrometer analysis, in the monoxenic cultures. In particular, we confirmed for the first time that P. viscosum, L. allorgei and P. uncinatum produced geosmin. Both the planktonic Phormidium tenue, a well known 2-methylisoborneol (MIB) producer and geosmin-producing attached cyanobacteria were closely associated with the occurrence of musty odor in Lake Kasumigaura. 相似文献
107.
J Yamamoto Y Shimamura H Nakahara Y Koishi M Kougo H Ohtani H Watanabe M Ishii M Ohmura 《Canadian Metallurgical Quarterly》1997,132(7):785-788
The leakage of pancreatic juice is the most serious complication after pancreatoduodenectomy. In an attempt to lessen the incidence of this complication, we have developed a simple technique for the anastomosis of pancreatogastrostomy. Since March 14, 1995, we have already performed surgical procedures on 8 cases of pancreatogastrostomy using this technique and as yet have never experienced fatal complications. We report the autopsy findings of pancreatogastric anastomosis histologically. The specimen taken from the anastomosis reveals good mucosal continuity. This result suggests the importance of reliable sutures between the pancreatic parenchyma and the full thickness of the gastric wall for the anastomosis of pancreatogastrostomy. 相似文献
108.
Huzo Kato Kohichi Ohtani Takehru Kohri Masahiro Morikura Masahiro Umehira Shuji Kubota 《International Journal of Satellite Communications and Networking》1988,6(3):289-300
Devices and architectures for on-board SCPC (single channel per carrier) multi-carrier demodulators suitable for use in satellites to be launched between the present and the year 2000 are discussed in the light of trends in the development of device technology towards lower on-board weight and power consumption. It is shown that at the present time (equivalent to about 1990 for on-board use). The choice of demodulation scheme depends on the number of channels available for regeneration on board the satellite. The total weight and power consumption for several suitable on-board multicarrier demodulation schemes are predicted for 1990, 1995 and 2000, as functions of the number of channels to be regenerated. 相似文献
109.
T Hosoki M Mitomo S Chor N Miyahara M Ohtani K Morimoto 《Canadian Metallurgical Quarterly》1997,38(3):422-427
PURPOSE: To assess the visualization of tumor vessels in hepatocellular carcinoma (HCC) by power Doppler sonography. MATERIAL AND METHODS: We examined 40 patients with 47 HCC lesions by means of power Doppler sonography and compared its visualization of tumor vessels with those of color Doppler and angiography. RESULTS: In 38 (81%) of the 47 lesions, power Doppler sonography improved the visualization of tumor vessels compared with color Doppler sonography; in the remaining lesions no significant difference was noted. In lesions located within 7 cm in depth, there was no significant difference between power Doppler sonography and angiography. In 10 (83%) out of 12 small (< or = 2 cm in diameter) lesions and in 11 (85%) out of 13 hypovascular lesions, power Doppler sonography performed considerably better than angiography. In deeper-seated lesions, however, angiography was significantly superior to power Doppler sonography. CONCLUSION: Power Doppler sonography is more sensitive in detecting the fine tumor vessels in most HCCs than color Doppler sonography. In addition, power Doppler sonography can replace angiography in evaluating tumor vascularity in HCCs except in lesions that are deep-seated or located near the heart. In these lesions, angiography can complement power Doppler sonography in demonstrating tumor vessels. 相似文献
110.
Ryuichi Shimokawa Michio Tajima Masatoshi Warashina Yusaku Kashiwagi Hitoshi Kawanami 《Solar Energy Materials & Solar Cells》1997,48(1-4)
We report the correspondence between the photoluminescence (PL) measurement, monochromatic-light-beam-induced current (MBIC) measurement and defect delineation in polycrystalline cast-Si solar cells. It was found that the peak of the band-edge PL emission in the hydrogenerated and non-hydrogenerated cast-Si shifted from 1.093 eV in the single crystalline CZ-Si to 1.075 eV at room temperature and the band-edge PL mapping corresponded with the MBIC mapping and defect delineation pattern if excluding the surface damages delineated by the MD-1 etchant. 相似文献