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961.
Jin Chen  Ping Wang  Qian Wan 《Tetrahedron》2010,66(13):2277-20035
A method by which to accomplish formal threonine ligation has been developed. The method accomplishes ligations of two peptide domains. We have also demonstrated the ability to successfully ligate two independent glycopeptide domains.  相似文献   
962.
Trger's base (TB) is a well-known chiral molecule with rigid concave shape that makes it applicable in different areas such as superamolecular chemistry,molecular recognition,biological labeling,and so on.In this article,we briefly summarize some recent research progress in the optoelectronic properties of novel TB analogues and their applications in optoelectronic field with emphasis on the developments achieved in our group.  相似文献   
963.
ZnS nanoribbon film has been successfully prepared by solvothermal treating of Zn foil and S powder in hydrazine hydrate without any surfactant and post-high temperature treatment. The prepared samples were characterized by XRD, SEM and PL. Results show that the obtained films were with high crystallinity and uniformity. The obtained samples were used as a photocatalyst for degradation of dye X-3B, and results show that the dye can be photocatalytically degraded with high rate by as-prepared ZnS nanoribbon film under UV light irradiation.  相似文献   
964.
K3C60, single crystal film was prepared on the cleaved (111) surface of C60, single crystal. Synchrotron radiation angle-resolved photoemission spectra were measured at normal emission with sample temperature at × 150K. Up to four subpeaks of LUMO-derived band were observed. These sub-peaks exhibit distinct energy dispersions which resemble in general the theoretical ones calculated for K3C60 at low temperature with the so-called one-dimensional disordered structure. But there is large deviation of experimental sub-band intervals from the theoretical values. This result is meaningful for the studies of the physical properties of alkali-doped C60 solids, e.g. the mechanism for superconductivity.  相似文献   
965.
本阐明了JP3—1型示波极谱仪电源及显示系统的工作原理,并举例说明这两部分的故障维修。  相似文献   
966.
通过对特丁基杯[4]芳烃的酚羟基的选择性醚化制备了一系列一烃基,1,3-二烃基和四烃基醚,烃基分别含有缩醛、酰胺、氰基等活泼官能团.醚化反应的区域选择性主要取决于使用的碱的种类和反应时间的长短.  相似文献   
967.
Copolymerization of acrylic acid and p‐chloromethylstyrene (p‐CMS) in dioxane initiated with α,α′‐azobisisobutyronitrile was carried out to produce macroinitiator P(AA‐co‐CMS) containing PhCH2Cl group at 65°C. Then methyl methacrylate was grafted onto P(AA‐co‐CMS) backbone using PhCH2Cl group as an initiation site and FeCl2/triphenyl phosphine complex as a catalyst. The resulted copolymer (AA‐co‐CMS)‐g‐PMMA with a comb‐like branched structure has a hydrophilic backbone (PAA) and hydrophobic side chains (PMMA). Compositions and structures of macroinitiator and the grafted product of P(AA‐co‐CMS)‐g‐PMMA were determined by 1H‐NMR, infrared (IR), and gel permeation chromatography (GPC). The average graft number, the average length of branch chains, the graft ratio, and the graft efficiency were investigated. The swelling behavior of the comb‐like branched polymer was also investigated. The gradual increase of swelling ratios was accompanied by an increase of pH and temperature. The kinetic exponents indicated that the swelling transport mechanisms transformed from Fickian diffusion to non‐Fickian transport as the decreasing pH. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
968.
We prove that boundary derivatives of the phases of inner functions exist and are positive almost everywhere, but those of outer functions, on the other hand, have zero mean on the boundary. The concepts and results have definitive applications to the definitions of instantaneous frequency and mono‐components complying with requirements in physics and contemporary study of analytic signals. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
969.
讨论临界情况下模糊矩阵对策的性抽,对模型问题各种情况给出了临界值c*的定义,证明了当d(f1,f2)<ε≤c*时,模糊矩阵对策模型问题关于价值函数f1(x)、f2(x)具有连续依赖性和可调和性。  相似文献   
970.
Herein we introduce a straightforward, low cost, scalable, and technologically relevant method to manufacture an all-carbon, electroactive, nitrogen-doped nanoporous-carbon/carbon-nanotube composite membrane, dubbed “HNCM/CNT”. The membrane is demonstrated to function as a binder-free, high-performance gas diffusion electrode for the electrocatalytic reduction of CO2 to formate. The Faradaic efficiency (FE) for the production of formate is 81 %. Furthermore, the robust structural and electrochemical properties of the membrane endow it with excellent long-term stability.  相似文献   
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