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1.
Two novel heterometallic trinuclear incomplete cubane-like clusters [(CH3CH2)4N][{M2CuS4}(edt)2(PPh3)] (M = Mo, W) have been synthesized by reaction of [(CH3CH2)4N]2[M2S4(edt)2] (M = Mo, W) with Cu(PPh3)2(dtp) [where edt is 1,2-ethane-dithiolato ligand, dtp is S2P(OCH2CH3)2−]. The two crystals are isomorphous in space group P1 (No. 1). The unit cell contains two independent molecules, but the two discrete anions have the same orientation for the PPh3 ligands along one axis so the space group is undoubtedly non-centrosymmetric. The discrete anion contains two edt ligands and one PPh3 ligand attached to one incomplete cubane-like cluster core {M2CuS4}3+ (M = Mo, W). The bond lengths of Mo---Mo[W---W] and the two Mo---Cu[W-Cu] are 2.852(2)[2.844(1)], 2.802(2)[2.765(3)], 2.760(2)[2.762(3)] Å, respectively. The M 2S4(edt)2 (M = Mo, W) moiety remains almost unchanged, except that for the compound 1 the Mo=S double bond length elongates from av. 2.10 to av. 2.165 Å. The title clusters provide a new type of unsymmetric μ2-bridging sulphido ligand. The incomplete cubane-like cluster core {Mo2CuS4}3+ of compound 1 is distorted because the two Cu---μ2---S bond lengths are significantly different (2.313 Å and 2.409 Å), but the core {W2CuS4}3+ of compound 2 has approximately Cs symmetry. The IR spectra of the two title clusters and two starting materials are assigned. 相似文献
2.
The thiotungstate [Et4N]2[OW(WS4)2], [Et4N]2.1, containing the linear [[S2W(VI)(mu-S)2]2W(IV)=O] core, was prepared from [Et4N]2[WS4] in the presence of the sulfide scavenger Cd2+. Addition of 1,2-bis(o-diphenylphosphinophenyl)ethane (diphosphine) and Cu+ or Ag+ to solutions of 1 in MeCN/DMF led to coordination of the (diphosphine)Cu/Ag fragments to the terminal sulfido ligands of 1, yielding novel linear pentanuclear, heterometallic clusters [mu-[OW(IV)(DMF)(W(VI)S4)2][M(diphosphine)]2], 2 (M = Cu) and 3 (M = Ag). Along with 2, the trinuclear cluster [[mu-(W(VI)S4)[Cu(diphosphine)(2)]], 4, was also obtained. The molecular and crystal structures of [Et4N]2.1, 2.MeCN, 3.MeCN, and 4.2MeCN.CH2Cl2 have been determined. 相似文献
3.
Sangni Jiang Wenliang Wang Lihua Dong Xinxin Yan Shengran Li Weikang Mei Xintao Xie Yuanhua Zhang Sanrong Liu Prof. Xifei Yu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12589-12598
Choline phosphate lipids have been designed and developed as new-generation zwitterionic nanocarriers with excellent biocompatibility and bioorthogonality to provide a more programmable performance for cancer therapy. However, there is a lack of spatiotemporal and reversible control for drug release at target tumor cells, which can lead to severe adverse effects to normal tissue and discounted treatment outcome. Here, light-inducible Lip-cRGDfk/ICG/Dox liposomes were developed for synergistic cancer therapy. ICG can effectively convert light energy into selective heating in a local environment upon laser irradiation, thus inducing thermal ablation of tumor cells, and further reversibly trigger the spatiotemporal release of anticancer drugs (Dox) at tumor cells due to the conformation transformation of CP lipids to synergistically kill tumor cells. That Lip-cRGDfk/ICG/Dox exhibited a significant improvement for breast cancer therapy in vitro and in vivo is also demonstrated, thus it can serve as an efficient platform to noninvasively and spatiotemporally control the activation of cytotoxicity at tumor cells for precision cancer therapy. 相似文献
4.
Xintao Wang Feng Qin Lijuan Jing Qiang Zhu Famei Li Zhili Xiong 《Biomedical chromatography : BMC》2013,27(3):371-376
A sensitive, rapid and selective ultra‐performance liquid chromatography–tandem mass spectrometric (UPLC‐MS/MS) method was developed for the determination and pharmacokinetic study of domperidone in human plasma. Diphenhydramine was used as the internal standard. Plasma sample pretreatment involved a one‐step liquid–liquid extraction with a mixture of diethyl ether–dichloromethane (3:2, v/v). The analysis was carried out on an Acquity UPLCTM BEH C18 column. The mobile phase consisted of methanol–water containing 10 mmol/L ammonium acetate and 0.5% (v/v) formic acid (60:40, v/v). The detection was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode via electrospray ionizationsource with positive mode. Each plasma sample was chromatographed within 2.1 min. The standard curves for domperidone were linear (r2 ≥ 0.99) over the concentration range of 0.030–31.5 ng/mL with a lower limit of quantification of 0.030 ng/mL. The intra‐ and inter‐day precision (relative standard deviation) values were not higher than 13% and accuracy (relative error) was from ?7.6 to 1.2% at three quality control levels. The method herein described was superior to previous methods and was successfully applied to the pharmacokinetic study of domperidone in healthy Chinese volunteers after oral administration. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
5.
A Luminescent Metal–Organic Framework Thermometer with Intrinsic Dual Emission from Organic Lumophores 下载免费PDF全文
Hao Zhang Dr. Chensheng Lin Prof. Tianlu Sheng Dr. Shengmin Hu Chao Zhuo Dr. Ruibiao Fu Dr. Yuehong Wen Haoran Li Shaodong Su Prof. Xintao Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4460-4468
A new mixed‐ligand metal–organic framework (MOF), ZnATZ‐BTB, has been constructed as a luminescent ratiometric thermometer by making use of the intrinsic dual emission at cryogenic temperatures. Its twofold interpenetrated network promotes the Dexter energy transfer (DET) between the mixed organic lumophores. The temperature‐dependent luminescent behavior arises from the thermal equilibrium between two separated excited states coupled by DET, which is confirmed by Boltzmann distribution fitting. The small excited‐state energy gap allows ZnATZ‐BTB to measure and visualize cryogenic temperatures (30–130 K) with significantly high relative sensitivity (up to 5.29 % K?1 at 30 K). Moreover, it is the first example of a ratiometric MOF thermometer the dual emitting sources of which are widely applicable mixed organic ligands, opening up new opportunities for designing such devices. 相似文献
6.
7.
机械制造系统生产水平的综合评价 总被引:1,自引:0,他引:1
运用数理统计和模糊数学的某些概念,本文提出了一种评价机械制造系统生产水平的新方法,机械制造系统可以用模糊变换器来描述,这个模糊变换器比较客观和全面地揭示机械制造系统的内在规律。借助这个模糊变换器来综合评价机械制造系统具有很大的理论和实践价值,并为机械制造系统论奠定新的基础。无心磨削系统的实验研究证明了本文基本观点的正确性。 相似文献
8.
The present paper is concerned with the convergence problem of the variants of the Chebyshev–Halley iteration family with parameters for solving nonlinear operator equations in Banach spaces. Under the assumption that the first derivative of the operator satisfies the Hölder condition of order p, a convergence criterion of order 1+p for the iteration family is established. An application to a nonlinear Hammerstein integral equation of the second kind is provided. 相似文献
9.
Sheming Lu Yanxiong Ke Jianmin Li Shuxi Zhou Xintao Wu Wenxin Du 《Crystal Research and Technology》2003,38(11):1004-1008
Mixing the malonate (mal), 4,4′‐bipyridine, UO2(CH3COO)2 · 2H2O in different solvent condition gets two compounds (bpy)2(H2bpy)[UO2(mal)2(μ‐H2O)] · 8H2O (1) and (H2bpy)[UO2(mal)2] · 2H2O (2) . Both complexes contain seven‐coordinated pentagonal bipyramidal uranium center. Crystal 1 is mononuclear structure and crystal 2 contains dinuclear [(UO2)2(mal)2(μ2‐mal)2]4‐ subunit. Particularly, Crystal 2 forms the twodimensional supramolecular topology by hydrogen bonds. The sheet constructs from two sorts of chamber, of which the larger one has two water molecular guests. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Li Jianmin Zeng Huaqiang Ke Yanxiong Wang Quanming Wu Xintao 《Crystal Research and Technology》1997,32(3):475-479
The complex of [CU(CH3CHCOO)2(OPph)]2 has been synthesized and its X-ray crystal structure determined at room temperature, M = 975.96, tetragonal, space group: 141/a(#88), Dx = 1.39 g/ cm3, The final R is 0.067 for 2087 independent observed reflections with 1 > 3α(I). The molecule has an inversion center on the middle of the Cu Cu axis. The bond-length of the Cu Cu is 2.61/(2) Å. The coordinate polyhedron of Cu corresponds to a tetragonal bipyramid. The angle of Cu O P is significantly smaller than that of its adducts [Cu(O2CR)2L]2. 相似文献