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1.
王鼎盛* 《物理》2013,(4):287-292
对于中国学术界出版英文学术期刊现在是没有人反对的,而且一般地讲大家都会赞成要把它办好。但是对于在中国出版英文期刊的目的和作用,对于这些刊物和刊物论文的评价尺度、以及对于办刊的回报预期,从论文作者到读者,从出版社到相关的主管机构(如中国科学技术协会及其下属学会、国家自然  相似文献   
2.
Coarse-grained molecular dynamics simulations were carried out to investigate the dewetting behavior of a polymer thin film on partial wetting solid surface at the early stage of the dewetting process. Spontaneous dewetting is initiated by removing a band of strip from both the ends of the liquid polymer film which has achieved equilibrium. The solid-liquid interaction and temperature were varied to show their influence on the dewetting dynamics during dewetting as well as the shape evolution of the liquid ...  相似文献   
3.
A series of novel 2,4-diamino-pteridines(9a-1)were synthesized and evaluated as inhibitors of inducible nitric oxide synthase (iNOS)in vitro.It was found that 9a,9d,9e,9h,9i and 91 showed potent inhibitory activities similar to that of methotrexate(MTX),while the activities of 9b,9c,9f,9g,9j and 9k ale stronger than MTX.  相似文献   
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使用Togni试剂的三氟甲基化反应通常会产生等物质的量的邻碘苯酸作为副产物.使用Togni试剂作为双官能团化试剂,通过氢原子转移的策略开发了一种可见光诱导的、原子和步骤经济的芳香炔的氢三氟甲基化与远程的α-C(sp~3)-H的苯甲酸化接力反应.这两种转化的结合,不仅实现了100%的原子转化率,而且解决了芳香炔氢三氟甲基化的区域选择性问题.这一新型的策略提供了制备一系列高官能团化的含三氟甲基烯烃的重要途径.  相似文献   
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在对自然的探索和学习活动中,智慧和知识是一个相互作用和转化的过程.当智慧变成知识的时候,宛若鲜花变成干花,生机尽失;而当把知识还原成智慧的时候,便让过去的先贤再活了一回.学习的目的不光是要承传知识,更重要的是汲取智慧,智慧才是创新的源泉.本文试图以对话的方式展示一个中学生在物理学习过程中对知识与智慧的认识.  相似文献   
7.
Reactive oxygen species(ROS) plays a key role in human heart diseases.Glutathione peroxidase(GPX) functions as an antioxidant as it catalyzes the reduction of hydroperoxide.In order to investigate the antioxidant effect of human selenium-containing single-chain Fv(Se-scFv-B3),a new mimic of GPX,a model system of hydrogen peroxide(H2O2)-induced rat cardiac myocyte damage was established.The cardiac myocyte damage was characterized in terms of cell viability,lipid peroxidation,cell membrane integrity,and intracellular H2O2 level.The Se-scFv-B3 significantly reduced H2O2-induced cell damage as shown by the increase of cell viability,the decline of malondialdehyde(MDA) production,lactate dehydrogenase(LDH) release,and intracellular H2O2 level.So Se-scFvB3 may have a great potential in the treatment of human heart diseases induced by ROS.  相似文献   
8.
The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium(Ⅲ,Ⅳ,Ⅴ)complexes with N,O-or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent. The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO_3 or VOSO_4.Under the optimized conditions,an aniline yield of 42.5%and a TON of 48 with a high selectivity of above 99.9%was obtained using 0.2 mmol of[VO(OAc)_2]...  相似文献   
9.
The eudesmane derivative, (-)-10-epi-α-cyperone 1, is widely used as a chiral starting material for the synthesis of other fused-ring sesquiterpenes1. The first synthetic work was reported by Howe and co-workers via condensation of (+)-dihydrocarvone 2 with 1-diethylaminopentan-3-one methiodide in 32% yield2. Previously, our group reported the synthesis of compound 1 by treating ketone 2 with ethyl vinyl ketone (EVK) directly under different conditions1a, but the yields were not satisfacto…  相似文献   
10.
Proteins containing dinuclear Cu (II), Zn (II) centers play paramount roles in biology1. As mimetic of metal-dependent esterase, dinuclear Cu (II) and Zn (II) complexes have received a great deal of attentions2~6. They are of interest in the field of biomimetic chemistry to provide an improved understanding of the function of the biological sites and as potential catalysts for substrate oxidations. Schiff base type polydentate ligands which contain centeral hydroxyl group have been wid…  相似文献   
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