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991.
Na Xiang Weiping Zhou Shenghui Jiang Lijun Deng Yijiang Liu Zhuo Tan Bin Zhao Ping Shen Songting Tan 《Solar Energy Materials & Solar Cells》2011,95(4):1174-1181
Two novel trivalent metal porphyrin dyes, PMn-HT-SCN and PGa-HT-SCN, were designed, synthesized and firstly applied in dye-sensitized solar cells (DSSCs). These two dyes possess porphyrin donor modified with manganese (III) and gallium (III) as coordination metal and NCS as the second ligand, cyanoacrylic acid as electron-accepting moiety and 4-hexylthiophene as π-spacers. Each of the porphyrin showed different adsorption behavior and saturated coverage on the TiO2 surface. Between the two dyes, the PMn-HT-SCN-based DSSCs afforded the best photovoltaic performance: a short-circuit photocurrent density (Jsc) of 4.32 mA/cm2, an open-circuit photovoltage (Voc) of 0.61 V and a fill factor (FF) of 0.58, corresponding to a solar-to-electricity conversion efficiency of 1.53% under 100 mW/cm2 irradiation. 相似文献
992.
在pH =7.00的条件下,痕量锰对高碘酸钾氧化酸性铬蓝K有催化作用.实验表明,测定痕量锰的最佳条件为pH =7.00B-R缓冲溶液5.0mL,酸性铬蓝K1.20mL,高碘酸钾2.80mL,氨三乙酸1mL,加热时间4min,水浴温度90℃.催化体系和非催化体系的△A =0.081,线性相关系数r=0.9994. 相似文献
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随着锰产业的迅锰发展,国内高品位锰矿逐渐枯竭,有必要探索锰矿尾矿资源化利用技术。实验采用电场强化锰矿尾矿的湿法浸出过程,并探索其强化机理。通过C射线衍射(XRD)、X射线荧光分析(XRF)、扫描电镜(SEM)以及紫外可见漫反射光谱(UV—visDRS)等检测方法,分析了碳酸锰矿尾矿的结构和成分,以及浸出反应前后的物相变化行为,研究了强化浸出工艺条件。结果表明,电场可改变矿浆颗粒表面电荷分布,强化锰矿尾矿浸出过程。在电流密度为5000A/m^2、液固比6:1mL/g、矿酸比为1:0.7、温度为60℃、时间为1h时,锰浸出率可达94.23%,与同等条件不加电场时相比提高18%,尾矿锰含量由4.33%降到0.14%。 相似文献
997.
Haitao Yang Buming Chen Huanrong Liu Zhongcheng Guo Yongchun Zhang Xuelong Li Ruidong Xu 《International Journal of Hydrogen Energy》2014
An Al/conductive coating/α-PbO2–CeO2–TiO2/β-PbO2–MnO2–WC–ZrO2 composite electrode material was prepared through electrochemical oxidation co-deposition on an Al/conductive coating/α-PbO2–CeO2–TiO2 substrate. The effects of manganese nitrate concentration on the chemical composition, electrocatalytic activity, and stability of the composite anode material were investigated using energy dispersive X-ray spectroscopy, anode polarization curves, quasi-stationary polarization curves, electrochemical impedance spectroscopy, scanning electron microscopy, and X-ray diffraction. Results revealed that the WC and nano-ZrO2 content in the β-PbO2–MnO2–WC–ZrO2 composite coatings increased with increasing manganese nitrate concentration. Moreover, the highest values of 6.61 wt% and 3.51 wt%, respectively, were achieved at 80 g L−1 manganese nitrate. PbO2 content decreased and MnO2 content increased with the increasing manganese nitrate concentration; both the descending and ascending trends were nonlinear. The Al/conductive coating/α-PbO2–CeO2–TiO2/β-PbO2–MnO2–WC–ZrO2 composite electrode obtained at 80 g L−1 manganese nitrate concentration in plating solution exhibited reduced overpotential for oxygen evolution (0.610 V at 500 A m−2), highest electrocatalytic activity, longest service life (360 h at 40 °C in 150 g L−1 H2SO4 solution at 2 A cm−2), and lowest cell voltage (2.75 V at 500 A m−2). Furthermore, the composite coating obtained with 80 g L−1 manganese nitrate had uniform crystal grains. The deposit formed was flat, dense, and crackless. 相似文献
998.
《腐蚀工程科学与技术》2013,48(4):432-438
AbstractThe open circuit potential of the Mn electrode is followed in aerated solutions of Cl?, Br?, I?, SO?&SetFont Typeface="44";24, CrO?&SetFont Typeface="44";24, CO?&SetFont Typeface="44";23 and NO?2 with different concentrations, till steady state values are attained. In all solutions studied, the steady state potentials are approached from negative values indicating oxide film growth. The rate of oxide film thickening is determined from the linear relationship between the open circuit potential and the logarithm of immersion time, t, as evident from the relation: E?=?a+b logt, where a and b are constants. Oxide film growth is assumed to occur by ion conduction under a high field. The rate of oxide film thickening depends on anion type and concentration. The concentration of the inhibitive anions, CrO&SetFont Typeface="44";2?4, CO&SetFont Typeface="44";2?3 and NO?2 that can withstand a certain concentration of the aggressive ions, Cl?, Br?, and I?, varies according to the relation: logCinh.?=?A+n logCagg., where A and n are constants. 相似文献
999.
简述云南文山斗南锰业股份有限公司斗南锰矿白姑矿段F3断层以东至19号堪探线之间V7薄矿体的回收工作,在残矿回收工作过程中,以安全第一为原则,科学管理为手段,在现有技术条件下,充分回收有限的矿产资源,对残矿进行回收,进一步延长了矿山服务年限。 相似文献
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