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Jianfeng Lu Xiaobao Xu Zhihong Li Kun Cao Jin Cui Yibo Zhang Prof. Yan Shen Yi Li Prof. Jun Zhu Prof. Songyuan Dai Prof. Wei Chen Prof. Yibing Cheng Prof. Mingkui Wang 《化学:亚洲杂志》2013,8(5):956-962
Anchoring groups are extremely important in controlling the performance of dye‐sensitized solar cells (DSCs). The design and characterization of sensitizers with new anchoring groups, in particular non‐carboxylic acid groups, has become a recent focus of DSC research. Herein, new donor? π? acceptor zinc? porphyrin dyes with a pyridine ring as an anchoring group have been designed and synthesized for applications in DSCs. Photophysical and electrochemical investigations demonstrated that the pyridine ring worked effectively as an anchoring group for the porphyrin sensitizers. DSCs that were based on these new porphyrins showed an overall power‐conversion efficiency of about 4.0 % under full sunlight (AM 1.5G, 100 mW cm?2). 相似文献
994.
Yongjin Xu Beisheng Kang Xuetai Chen Yuanba Cai Yonghan Hu Jiaxi Lu 《Journal of Cluster Science》1992,3(2):167-177
Complex Co4mp4(Hmp)(PBu
3
n
)3 (1) (H2mp=o-Mercaptophenol) was obtained from the reaction of CoCl2 and H2mp in the presence of PBu
n
3 and NaOMe with restricted oxidation. X-ray crystallographic data: triclinic, space group
,a=15.657(5) Å,b=20.469(8) Å,c=12.383(3) Å,=93.59(3)°, =112.45(2)°, =93.65(3)°,V=3648.7 Å3,Z=2,D
c
=1.33 g/cm3;R=0.065. The molecule consists of four cobalt atoms unsymmetrically bridged by S or S and O atoms from four of the five mp ligands. The fifth mp is terminally chelated to Co(4) which is in a distorted trigonal bipyramidal geometry, while Co(1)-Co(3) are square pyramidal. Atom Co(2) is bonded to Co(1) and Co(3) (average distance 2.632 Å) with strong interactions while Co(4) is only loosely connected to Co(1) (3.402 Å) and Co(3) (2.956 Å) through oxygen bridges and a hydrogen bond. The different coordination environments O2S2P, S4P, and O4S of the cobalt atoms make the molecule highly asymmetrical. XPS fitting data confirm the difference of the Co atoms. FABMS data indicate the possible fragmentation routes. The complex is paramagnetic with eff=5.2 B. 相似文献
995.
Shukun Xu Michael Sperling Bernhard Welz 《Fresenius' Journal of Analytical Chemistry》1992,344(12):535-540
Summary Cadmium and copper at the g/g to ng/g level in plant and animal tissue reference materials, and at the g/l level in urine were determined by flame atomic absorption spectrometry using on-line sorbent extraction preconcentration based on flow injection techniques. Bonded silica reversed phase sorbent with octadecyl functional groups (RP-C 18), packed in a 100 l column, was used to collect the diethylammonium-N,N-diethyldithiocarbamate (DDTC) complex formed on-line in the sample digests at low pH. Methanol was used to elute the analyte chelates directly into the nebulizer-burner system of the spectrometer. Small air segments introduced before and after elution prevented the eluent from mixing with the sample solution and increased the sensitivity. A sampling frequency of 85/h could be obtained with a sample loading time of 30 s at a flow rate of 4.0 ml/min. The enrichment factor for both elements was 20 and the enhancement factors, including the effect of the organic solvent and with the flow spoiler removed, were 126 and 114 for cadmium and copper, respectively. The detection limits (3) were 0.15 g/l for cadmium and 0.2 g/l for copper. The precision was 2.3% and 1.4% r.s.d. for 10 g/l Cd and 45 g/l Cu, respectively (n=11). Results for the determination of cadmium and copper in various biological reference materials were typically in good agreement with certified values. Low recoveries were observed, however, for cadmium in samples containing high levels of copper and/or iron, such as bovine liver.On leave from Flow Injection Analysis Research Center, Institute of Applied Ecology, Academia Sinica, Shenyang, China 相似文献
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稳定回归法用于复方氯丙嗪片的测定 总被引:1,自引:1,他引:1
本文应用稳定回归法用于紫外重叠光谱的分析。以复方氯丙嗪为例,不经分离,测定了盐酸氯丙嗪和盐酸异丙嗪的含量。与最小二乘回归法比较,提高了测定结果的准确度和精密度。结果满意。 相似文献
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