首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   353篇
  免费   34篇
  国内免费   1篇
化学   340篇
晶体学   7篇
力学   2篇
数学   17篇
物理学   22篇
  2024年   1篇
  2023年   2篇
  2022年   5篇
  2021年   14篇
  2020年   16篇
  2019年   8篇
  2018年   7篇
  2017年   6篇
  2016年   13篇
  2015年   14篇
  2014年   13篇
  2013年   27篇
  2012年   19篇
  2011年   28篇
  2010年   21篇
  2009年   14篇
  2008年   22篇
  2007年   18篇
  2006年   23篇
  2005年   17篇
  2004年   23篇
  2003年   14篇
  2002年   9篇
  2001年   3篇
  2000年   3篇
  1999年   3篇
  1998年   3篇
  1996年   7篇
  1995年   1篇
  1994年   4篇
  1993年   1篇
  1992年   3篇
  1991年   3篇
  1990年   3篇
  1988年   1篇
  1984年   3篇
  1983年   3篇
  1981年   2篇
  1980年   1篇
  1979年   2篇
  1977年   1篇
  1976年   1篇
  1973年   2篇
  1972年   2篇
  1916年   1篇
  1896年   1篇
排序方式: 共有388条查询结果,搜索用时 15 毫秒
361.
Keratin 1 (KRT1) is overexpressed in squamous carcinomas and associated with aggressive pathologies in breast cancer. Herein we report the design and preparation of the first Trp-based red fluorogenic amino acid, which is synthetically accessible in a few steps and displays excellent photophysical properties, and its application in a minimally-disruptive labelling strategy to prepare a new fluorogenic cyclopeptide for imaging of KRT1+ cells in whole intact tumour tissues.

Trp(redBODIPY) is the first red-emitting Trp-based amino acid for the preparation of fluorogenic peptides with retention of target binding affinity.  相似文献   
362.
A series of soluble trinuclear copper(I) and silver(I) complexes containing bicapped diynyl ligands, [M(3)(micro-dppm)(3)(micro(3)-eta(1)-C triple bond CC triple bond CR)(2)]PF(6) (M = Cu, R = Ph, C(6)H(4)-CH(3)-p, C(6)H(4)-OCH(3)-p, (n)C(6)H(13), H; M = Ag, R = Ph, C(6)H(4)-OCH(3)-p), has been synthesized and their electronic, photophysical, and electrochemical properties studied. The X-ray crystal structures of [Cu(3)(micro-dppm)(3)(micro(3)-eta(1)-C triple bond CC triple bond CPh)(2)]PF(6) and [Cu(3)(micro-dppm)(3)(micro(3)-eta(1)-C triple bond CC triple bond CH)(2)]PF(6) have been determined.  相似文献   
363.
Li CK  Lu XX  Wong KM  Chan CL  Zhu N  Yam VW 《Inorganic chemistry》2004,43(23):7421-7430
A series of luminescent dinuclear gold(I) complexes with different crown ether pendants, [Au(2)(PwedgeP)(S-B15C5)(2)] [S-B15C5 = 4'-mercaptobenzo-15-crown-5, P(wedge)P = bis(dicyclohexylphosphino)methane (dcpm) (1), bis(diphenylphosphino)methane (dppm) (2)] and [Au(2)(P(wedge)P)(S-B18C6)(2)] [S-B18C6 = 4'-mercaptobenzo-18-crown-6, P(wedge)P = dcpm (3), dppm (4)], and their related crown-free complexes, [Au(2)(P(wedge)P)(SC(6)H(3)(OMe)(2)-3,4)(2)] [P(wedge)P = dcpm (5), dppm (6)], were synthesized. The low-energy emission of the mercaptocrown ether-containing gold(I) complexes are tentatively assigned as originated from states derived from a S --> Au ligand-to-metal charge transfer (LMCT) transition. The crown ether-containing gold(I) complexes showed specific binding abilities toward various metal cations according to the ring size of the crown pendants. Spectroscopic evidence was provided for the metal-ion-induced switching on of the gold...gold interactions upon the binding of particular metal ions in a sandwich binding mode.  相似文献   
364.
365.
366.
In this review, the synthesis, electronic absorption and luminescent properties of a series of branched alkynylpalladium(II) and -platinum(II) phosphine complexes with different alkynyl backbones and some of their structurally related complexes in the literature will be discussed. With the growing research interest in the potential application of these complexes in the field of non-linear optics (NLO), the two-photon absorption (TPA) properties and the corresponding structure–property relationships of selected luminescent branched platinum(II) bis-alkynyl complexes will also be described.  相似文献   
367.
A hexanuclear gold(I) selenido cluster and its sulfido counterpart, [Au6{μ‐Ph2PN(CH2o‐Py)PPh2}33‐E)2](ClO4)2 (E = S, Se), with bridging bis(diphenylphosphino)amine ligands were synthesized and characterized. The X‐ray crystal structure of the selenido cluster was determined, with the gold core possessing a distorted heterocubane structure. Intramolecular aurophilic interactions with short Au(I)?Au(I) contacts of around 3.09–3.13 Å were observed. The complexes were found to emit strongly in the solid state with orange to red emission colors. Their electronic absorption and emission properties were also investigated.  相似文献   
368.
We investigate the effects of an external magnetic field in the gap structure of a color superconductor with three massless quark flavors. Using an effective theory with four-fermion interactions, inspired by one-gluon exchange, we show that the long-range component B of the external magnetic field that penetrates the color-flavor locked phase modifies its gap structure, producing a new phase of lower symmetry. A main outcome of our study is that the B field tends to strengthen the gaps formed by Q-charged and Q-neutral quarks that coupled among themselves through tree-level vertices. These gaps are enhanced by the field-dependent density of states of the Q-charged quarks on the Fermi surface. Our considerations are relevant for the study of highly magnetized compact stars.  相似文献   
369.
370.
New exact laminar convective temperature solutions for rectangular ducts with constant heat flux per unit length have been derived in uniform fashion for a variety of Dirichlet and Neumann boundary conditions. Those with null Dirichlet boundary conditions satisfy the hypothesis of a general inequality theorem. Consequences of the theorem are shown for the velocity and thermal fields of rectangular and elliptical ducts, which provide rigorous bounds for intermediate contours.
Résumé Quelques solutions nouvelles exactes du problème de la convection laminaire de la chaleur dans les tuyaux de section rectangulaire ont été déduites d'une façon uniforme pour différentes conditions aux limites selon Dirichlet et Neumann. L'hypothèse d'un théorème général d'inégalité est satisfaite lorsque les conditions aux limites sont homogènes selon Dirichlet. Les conséquences de ce théorème sont montrées pour les champs de vitesse et de température dans les tuyaux rectangulaires et elliptiques, ce qui fournit des bornes précises pour des domaines intermédiaires.
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号