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meso -四 (α ,α ,α ,α - 0 -苯乙酰苯 )卟啉诱导的单抗 (MAb)导致meso -四 (α,α ,α ,α - 0 -苯乙酰苯 )卟啉Soret带来巨大红移 ,并且在meso -四 (α ,α ,α ,α - 0 -苯乙酰苯 )卟啉上产生巨大的诱导Cotton效应 (ICD) .借用ICD定量分析meso -四 (α ,α ,α ,α - 0 -苯乙酰苯 )卟啉同抗体的结合 ,表明在抗体超过meso -四 (α ,α ,α ,α - 0 -苯乙酰苯 )卟啉的情况下 ,既有 1∶1结合 ,又有 2∶1结合〔结合位点 :meso -四 (α ,α ,α ,α - 0 -苯乙酰苯 )卟啉〕 相似文献
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Constituting the artificial carbon cycle,for example,through recycling CO2 and converting CH4 to value-added fuels and chemicals with solar energy,offers a sustainable future for humankind to tackle the global environmental issues and energy crisis.However,significant bottlenecks remain in such photocatalytic conversion,mainly related to the reaction activity and product selectivity.Herein,we share our efforts and systematic research progress on addressing the double bottlenecks for achieving solar-driven artificial carbon cycle,with specifically focusing on the photocatalytic CO2 and CH4 conversion.We further elucidate the common fundamentals behind various designed photocatalytic materials systems.Toward future development,we highlight the opportunities and challenges in the research field. 相似文献
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Fashui?HongEmail author Xuefeng?Wang Chao?Liu Guoxing?Su Weiping?Song Kang?Wu Ye?Tao Guiwen?Zhao 《中国科学B辑(英文版)》2003,46(1):42-50
It was studied by spectroscopy that PSII reaction center complex consisting of three polypeptides, D1, D2 and Cytb559, were purified from PSII particle of CeCl3 treated spinach. The results of the experiment show that Ce3+ could improve the growth of spinach, and accelerate electron transport of PSII particles. Of chl-a of UV-Vis spectrum of
D1/D2/Cytb559 complex, Soret band was blue-shifted by 3 nm and Q band by 2 nm, respectively, and the fluorescence emission
peak was blue-shifted by 5 nm in CeCl3-treated spinach compared with the one in control. By the extended X-ray absorption fine structure (EXAFS) spectroscopy methods,
it has been found that Ce3+ is coordinated with 8 nitrogen atoms in the first coordination shell with Ce-N bond length of 0.253 nm, and Ce3+ with 6 oxygen atoms in the second coordination shell with Ce-O bond length of 0.32 nm. However, the secondary structure of
D1/D2/Cytb559 complex by circular dichroism (CD) spectroscopy has no significant change after CeCl3 treated. It might be that Ce3+ binds to porphyrin rings of chlorophyll and oxygen of amino acid residue of polypeptide in D1/D2/Cytb559 complex, and then
accelerates the primary reaction of PSII, intensifies function of P680+ primary electron donor of D1/D2/Cytb559, but there is little change in conformation of PSII reaction center complex. 相似文献
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On the way of the "1990 International Trans-Antarctic Expedition", the first author of this paper, the Chinese member of the expedition, collected 104 snow samples in 25-cm surface snow along a 5986-km route on Antarctic ice sheet from west to east. The geographical distribution of δD across the Antarctica by the longest route is obtained from stable isotope analysis for the first time. After discussing regional differences of physical geographic conditions, maritime-continental influence, altitudes and latitudes at sampling sites, the distribution of δD is considered to have a close relation to latitudes, but the topographic effect is prominent in some particular regions. The mean annual temperature at sampling site and its relationship with δD in surface snow covering Antarctica from west to east are discussed also. The δD-temperature gradient from the south end of Antarctic Peninsula to Vostok obtained in this paper is very close to that in Terre Adelie Land obtained by predecessors. The snow-dri 相似文献
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圆二色谱和紫外可见光谱研究抗体-卟啉的相互作用 总被引:1,自引:0,他引:1
圆二色谱(CD)和紫外可见光谱(UV-VIS)可用来研究单克隆抗体(McAb)-卟啉之间的相互作用,卟啉形成McAb-卟啉复合物,在Soret带区域最大吸收峰有显著红移和增色现象,在350-450nm区域,形成复合物时能检测诱导的CD光谱。CD光谱遵守朗伯-比尔定律,显示等吸收行为。McAb-卟啉复合物的紫外可见吸收及诱导的CD光谱在PH6-11的范围内保持不变,说明复合物异常稳定,也说明McAb-卟啉结合位点之间疏水相互作用是主要因素。 相似文献