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991.
为了提高直热式太阳能海水淡化系统的设计与操作,运用热经济孤立化方法,对直热式太阳能海水淡化系统进行分析,获得了系统最优化操作参数。同时讨论了设备使用年限、最高海水温度、进料海水单价对年度化费用的影响。结果表明:当拉格朗日乘子分别为¥4.85/kJ、¥0.59/kJ、¥0.40/kJ、¥0.19/kJ时,系统实现热经济孤立化。此时,闪蒸温度为58.6 ℃,蒸发温度为35 ℃时,年度化费用为¥4 332.81/a。年度化费用随设备使用年限的增加而减小,随最高海水温度的升高而降低,随进料海水单价的升高而增加。 相似文献
992.
Chemical fixing of xanthene dye (eosin Y) on the surface of TiO2 electrode was carried out by modifying the electrode with silane-coupling reagent to obtain stable dye-sensitized TiO2 electrode. Such silane modification can not only evidently enhance the stability of dye-sensitized TiO2 electrode but also improve the energy conversion efficiency of the assembled cells by increasing short-circuit photocurrent (Jsc) and open-circuit photovoltage (Voc). It was found that the improvements of cell performances differ depending on the composition of the electrolyte. The optimum cell of the cell performance was achieved in the electrolyte with 0.5 mol/L TBAI/0.05 mol/L 12/EC:PC(3:1 w/w), yielding Jsc of 4.69 mA. cm-2, Voc of 0,595 V, fill factor (FF) of 0.64 and ηof 1,78%, Different spectroscopic techniques including UV-Vis spectra, fluorescence spectra, EIS and dark current measurements were employed to derive reasonable analysis and explanations. 相似文献
993.
JinMao Chen JianHui Hou YongFang Li XiaoWen Zhou JingBo Zhang XuePing Li XuRui Xiao Yuan Lin 《科学通报(英文版)》2009,54(10):1669-1676
A new kind of polythiophene derivative, Poly(3-{2-[4-(2-ethylhexyloxy)-phenyl]-vinyl}-2,2′-bithiophene) (PTh), was applied in dye-sensitized solar cell to extend the light response of nanocrystalline TiO2 electrode. UV-vis absorption and fluorescence spectra were employed to investigate the interaction of PTh with nanocrystalline TiO2. The absorption coefficient of the PTh was high in visible part of spec- trum, and the fluorescence emission of the PTh can be efficiently quenched by TiO2 nanoparticles ow- i... 相似文献
994.
The GaInP/GaAs/Ge triple-junction tandem cells with a conversion efficiency of 27.1% were fabricated using metalorganic chemical vapor deposition (MOCVD) technique. Temperature dependence of the spectral response measurements of the GaInP/GaAs/Ge tandem cell was performed by a quantum effi-ciency system at temperatures ranging from 25℃ to 160℃. The red-shift phenomena of the absorption limit for all subcells were observed with increasing temperature, which is dued to the energy gap nar-rowing with temperature. The short-circuit current densities (Jsc)of GaInP, GaAs and Ge subcells at room temperature calculated based on the spectral response data were 12.9, 13.7 and 17 mA/cm2, re-spectively. The temperature coefficient of Jsc for the tandem cell was determined to be 8.9 mA/(cm2·℃), and the corresponding temperature coefficient of the open-circuit voltage deduced from the se-ries-connected model was -6.27 mV/℃. 相似文献
995.
In this study, GFP mRNA in COS-7 cell and GFP-transfected COS-7 cell was detected in real time using phosphorothioate-modified
molecular beacon based on living cell imaging method. Results showed that phosphorothioate-modified molecular beacon still
kept the advantages of molecular beacon, such as, excellent selectivity, high sensitivity, and no separation detection. In
addition, this modification could significantly increase the nuclease resistance of molecular beacon. Phosphorothioate-modified
molecular beacon can efficiently reduce the false positive signal and improve the accuracy of living cell mRNA detection.
Supported by the National Key Basic Research Program (Grant No. 2002CB513110), International Technologies Collaboration Program
of China (Grant No. 2003DF000039), and National Natural Science Foundation of China (Grant Nos. 90606003 and 20620120107) 相似文献
996.
Solar-driven high temperature radiant cooling 总被引:1,自引:0,他引:1
Solar energy is widely used as one of the most important renewable energy. In addition to the growing applications of solar
PV and solar water heater, solar cooling is also considered very valuable and the related researches are developing fast because
of the synchronism between solar irradiance and building cooling load. Current studies mainly focus on the high temperature
solar collector technique and heat-driven cooling technique, while little concern has been paid to the transport process of
cooling power. In this paper, the high temperature radiant cooling is studied as an alternative way for transporting cooling
power, and the performance of the combination of radiant ceiling and solar cooling is also studied. From simulation and theoretical
analysis results, high temperature radiant cooling terminal shows better cooling power transportation ability against conventional
air-conditioning terminal, and its thermal comfort is improved. Experiment results indicate that radiant cooling can enhance
the chiller’s COP (Coefficient of Performance) by 17% and cooling power regeneration by 50%. According to analysis in this
paper, high temperature radiant cooling is proved to be suitable for solar cooling system, and out work can serve as a reference
for later system design and promotion.
Supported by the National Natural Science Foundation of China (Grant No. 50876064) 相似文献
997.
998.
基于天空偏振光分布模式的仿生导航定向机理初探 总被引:7,自引:0,他引:7
提出了一种利用天空偏振光分布确定仿生导航系统航向角的方法。该方法将理论分析和实验相结合,建立了天空偏振光分布的理论和实验模型;在深入分析模型的基础上,确定了为导航系统提供航向信息的导航参考线——太阳子午线;结合天文导航方法,确定太阳的相对位置。最后,建立地平坐标系为导航坐标系,举例说明了确定航向角的整个过程。 相似文献
999.
目的:研究P38α对人血管内皮细胞一氧化氮合酶(eNOS)基因启动子转录活性的影响.方法:利用硝酸还原酶法检测不同浓度氯化钴作用下人脐静脉血管内皮细胞-12(HUVEC-12)上清中的一氧化氮(NO)的含量.以pRL-TK为内参照,将已经构建好的pGL2-eNOS-p质粒分别与pGL3-BASIC、pcDNA3、p38a、及p38a(AF)共转染HUVEC-12细胞,利用双荧光素酶报告基因技术检测eNOS基因启动子转录活性,并在共转染的基础上加氯化钴刺激,并检测eNOS基因启动子转录活性.结果:氯化钴刺激下HUVEC-12细胞培养上清的NO含量随氯化钴作用浓度增加而提高,成功建立化学缺氧模型;p38a在正常和缺氧条件下均明显降低eNOS基因启动子的活性,可被无活性诱变体p38a(AF)逆转.结论:P38et下调人血eNOS基因启动子转录活性. 相似文献
1000.
通过现有铁源利用及碳冶金流程分析,提出了太阳能光伏非碳冶金概念.太阳能光伏非碳冶金研究包括高温冶炼、非碳还原介质的选择及还原-熔融三个方面.自主设计制造了1kg容量的太阳能非碳冶金系统,进行了三类非碳冶金实验.实验结果表明太阳能光伏非碳冶金在技术上可行,自主设计制造的太阳能光伏非碳冶金系统均能满足冶炼要求.高温冶炼实验光伏电池转换率9.8%,钢水热焓占总能量消耗5%;非碳还原制铁实验电解法电流效率平均为85.1%,最高可达97.6%;氢还原Fe2O3还原度影响因素由强到弱依次为:气氛、温度、时间、粒度.根据实验结果,研究还需深化,以寻求太阳能光伏非碳冶金系统更好的经济性、稳定性及可操作性. 相似文献