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排序方式: 共有814条查询结果,搜索用时 15 毫秒
1.
系统主要针对金属材料中氢同位素和氦的热解析研究而研制,系统原理图如图l所示。系统支路中设计消气剂床,用以避免金属氚化物解析时氚的排放问题;温度、压力和解析组分等由采集系统采集与分析。 相似文献
2.
Jing Lin CHEN Gang Qiang YIN Zhong Ning CHEN* State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Fuzhou 《中国化学快报》2003,(5)
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl… 相似文献
3.
Jing Ping WANG Qiang WU Jing Yang NIU* School of Chemistry Chemical Engineering Henan University Kaifeng 《中国化学快报》2002,13(9):915-918
It is becoming a focus to synthesize and assemble organic-inorganic materials, especially, to synthesize charge-transfer complexes formed by polyoxometalate and organic donors. They have attracted much attention because such complexes are active in their electric, magnetic and optic properties1-4, many investigations about them have been done and some crystal structures of them were reported5-6. But, the disadvantage of these crystals is instability at room temperature. According to the view… 相似文献
4.
通过对两个自然村的大骨节病的流行病学调查结果表明,患病率在17.2%,从X线检查病变部位都在干骺端,说明致病因素的持续作用仍在发展中,所采水样中微量元素低于国家饮水标准,在今后疾病的防治中,应根据营养条件,生态环境,元素比例,农作物的病害,制作相关的防治措施。 相似文献
5.
Nanostructure Pt Electrode Obtained via Self-assembly of Nanoparticles on Conductive Oxide-coated Glass Substrate 总被引:1,自引:0,他引:1
Self-assembly of platinum nanoparticles were applied to fabrication of counter electrode for dye-sensitized solar cells on conductive oxide-coated glass substrate. The present Pt electrode exhibits high exchange current density of 220 mA/cm^2, which is comparable to those prepared by electrodeposition, magnetron sputtering or thermal decomposition of platinum chloride. After analysis by transmission electron microscopy (TEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), it was found that the catalyst was structurally characterized as nanosized platinum metal clusters and was continuously arranged on electrode surface. The present nanostructure electrode had high electrocatalytic activity for the reduction of iodine in organic solution. 相似文献
6.
7.
Structural Features of a Polysaccharide from Centella asiatica 总被引:3,自引:0,他引:3
Xue Song WANG Jin You DUAN Ji Nian FANG* Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2004,15(2):187-190
Centella asiatica has been used as remedy for sodation, stabilization and against lepra, anabrosis1 in the oriental countries. The low-molecular-weight constituents in Centella asiatica have been investigated1. However, no polysaccharides have been reported. 1BI was the first polysaccharide isolated from C. asiatica, which had immunostimulating activity in vitro. In present study, we report the structural features of 1BI. Experimental Extraction, isolation and purification Dried C.… 相似文献
8.
Thermal decomposition kinetics of titanium hydride and Al alloy melt foaming process 总被引:3,自引:0,他引:3
YANG Donghui* HE Deping*& YANG Shangrun* . Department of Materials Science Engineering Southeast University Nanjing China . Department of Chemistry Nanjing University Nanjing China 《中国科学B辑(英文版)》2004,47(6):512-520
Metal foams, now one of research foci, are a newclass of materials with low densities and novel physi-cal, mechanical, thermal, electrical and acoustic prop-erties[1—8]. Demands from high-tech make Al alloyfoam, which has much higher specific strength than ofpure Al foam, the new development focus[9—11]. Melt foaming process is one of the approaches tofabricate Al foam and Al alloy foam and their porestructure (pore diameter and porosity) has close rela-tionship with the thermal decompo… 相似文献
9.
Four para-dialkylaminophenyl (PDAAP1-PDAAP4) bearing carboxyl groups were studied for application to the dye-sensitized solar cells (DSC). It was found the short spacer CH2 between carboxyl and dialkylaminophenyl chromophore in PDAAP3 and PDAAP4 led to highly efficient monochromatic incident photon-to-current conversion efficiencies (IPCE), however the long alkyl group C4H9 attached on aniline moieties in PDAAP2 and PDAAP4 favored improvement of open-circuit photovoltage. Thus, the solar cell sensitized by PDAAP4, having both short carboxyl groups CH2COOH and long alkyl groups C4H9, exhibited the IPCE maximum of 73% at 670 nm and overall energy conversion efficiency η of 3.06%, representing the highest IPCE and η values so far in dialkylaminophenyl-based organic dye-sensitized semiconductor solar cells. Taking advantage of the highly efficient sensitizing ability of PDAAP4 in far-red region, the data of IPCE above 630 nm of the solar cells were improved greatly by cosensitization with both N3 and PDAAP4. The influences of the TiO2 film thickness and the concentration of 4-tert-butylpyridine (TBP) in electrolyte were also investigated. 相似文献
10.
XU Long Ya * WANG Qing Xia LIN Li Wu XU Yi De Dalian Institute of Chemical Physics The Chinese Academy of Sciences Dalian Liaoning 《天然气化学杂志》1998,7(1):7-15
Ni/Si2催化剂具有较好的低碳烷烃与二氧化碳重整制合成气的反应性能,添加La2O3助剂和K2O助剂可提高催化剂活性和合成气收率,从而进一步改善催化剂的低碳烷烃与CO2重整制合成气的反应性能,研制的KLaNi/Si2催化剂,用于天然气与CO2重整反应制合成气可达97%的低碳烷烃转化率和95%以上的合成气收率。 相似文献