全文获取类型
收费全文 | 115篇 |
免费 | 8篇 |
专业分类
化学 | 100篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 9篇 |
物理学 | 10篇 |
出版年
2022年 | 6篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 6篇 |
2012年 | 7篇 |
2011年 | 11篇 |
2010年 | 1篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 6篇 |
2006年 | 5篇 |
2005年 | 12篇 |
2004年 | 5篇 |
2003年 | 11篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1996年 | 3篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有123条查询结果,搜索用时 15 毫秒
41.
Dr. Yoann Prado Dr. Marie‐Anne Arrio Dr. Florence Volatron Dr. Edwige Otero Dr. Christophe Cartier dit Moulin Dr. Philippe Sainctavit Dr. Laure Catala Prof. Dr. Talal Mallah 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6685-6694
The local symmetry and local magnetic properties of 6 nm‐sized, bimetallic, cyanide‐bridged CsNiCr(CN)6 coordination nanoparticles 1 and 8 nm‐sized, trimetallic, CsNiCr(CN)6@CsCoCr(CN)6 core–shell nanoparticles 2 were studied by X‐ray absorption spectroscopy (XAS) and X‐ray magnetic circular dichroism (XMCD). The measurements were performed at the NiII, CoII, and CrIII L2,3 edges. This study revealed the presence of distorted NiII sites located on the particle surface of 1 that account for the uniaxial magnetic anisotropy observed by SQUID measurements. For the core–shell particles, a combination of the exchange anisotropy between the core and the shell and the pronounced anisotropy of the CoII ions is the origin of the large increase in coercive field from 120 to 890 Oe on going from 1 to 2 . In addition, XMCD allows the relative orientation of the magnetic moments throughout the core–shell particles to be determined. While for the bimetallic particles of 1 , alignment of the magnetic moments of CrIII ions with those of NiII ions leads to uniform magnetization, in the core–shell particles 2 the magnetic moments of the isotropic CrIII follow those of CoII ions in the shell and those of NiII ions in the core, and this leads to nonuniform magnetization in the whole nanoobject, mainly due to the large difference in local anisotropy between the CoII ions belonging to the surface and the NiII ions in the core. 相似文献
42.
Subhi A. Al-Jibori Ali I. Abdullah Talal A. K. Al-Allaf 《Transition Metal Chemistry》2007,32(3):398-406
Palladium(II) and platinum(II) complexes containing mixed ligands N-(2-pyridyl)acetamide (AH) or N-(2-pyrimidyl)acetamide (BH) and the diphosphines Ph2P(CH2)
n
PPh2, (n = 1, 2 or 3) have been prepared. The prepared complexes [Pd(A)2(diphos)] or [Pd(B)2(diphos)] have been used effectively to prepare bimetallic complexes of the type [(diphos)Pd(μ-L)2M′Cl2] where M′ = Co, Cu, Mn, Ni, Pd, Pt or SnCl2; L = A or B. The prepared complexes were characterized by elemental analysis magnetic susceptibility, i.r. and UV–Vis spectral
data. 31P–{1H}-n.m.r. data have been applied to characterize the produced linkage isomers. 相似文献
43.
Talal F. Al-Azemi Hicham H. Dib Nouria A. Al-Awadi Osman M.E. El-Dusouqui 《Tetrahedron》2008,64(18):4126-4134
Compounds containing both carbonate and ester functionalities were synthesized and then subjected to online-GC gas-phase pyrolysis. The carbonate groups were cleaved selectively in all elimination reactions. The end products of the reaction were found to be affected by the nature of the substrate. The presence of hydrogen and carbonyl substituents on the carbon β to the carbonate group resulted in further product decomposition through a concerted six-membered transition state. Results from flash vacuum pyrolysis (FVP) and analysis of the GC data indicate that the cleavage of the carbonate group is fast, and that the slower secondary decomposition reactions are independent of the presence of the carbonate group. Spectroscopic analyses of the products are reported. 相似文献
44.
Jones LF Brechin EK Collison D Helliwell M Mallah T Piligkos S Rajaraman G Wernsdorfer W 《Inorganic chemistry》2003,42(21):6601-6603
The reaction of [NEt(4)](2)[Fe(2)OCl(6)] with sodium benzoate, 4,6-dimethyl-2-hydroxypyrimidine (dmhp), and 1,1,1-tris(hydroxymethyl)ethane (H(3)thme) gives the undecametallic compound [NEt(4)][Fe(11)O(4)(O(2)CPh)(10)(thme)(4)(dmhp)(2)Cl(4)]. X-ray crystallography, EPR spectroscopy, bulk magnetic susceptibility studies, and low-temperature single-crystal magnetic measurements were used to characterize the compound. Magnetic measurements indicate an S = (11)/(2) ground state with the parameters g = 2.03 and D = -0.46 cm(-)(1). Single-crystal magnetic studies show hysteresis of molecular origin at T < 1.2 K with fast quantum mechanical tunneling at zero field. 相似文献
45.
46.
Fleury B Volatron F Catala L Brinzei D Rivière E Huc V David C Miserque F Rogez G Baraton L Palacin S Mallah T 《Inorganic chemistry》2008,47(6):1898-1900
The grafting of a monolayer of 6 nm superparamagnetic cyanide-bridged CsNiCr nanoparticles was achieved on a Ni(II)-functionalized Si(100) substrate; magnetic studies reveals that the grafted nanoparticles are nearly magnetically isolated within the monolayer. 相似文献
47.
Catala L Mathonière C Gloter A Stephan O Gacoin T Boilot JP Mallah T 《Chemical communications (Cambridge, England)》2005,(6):746-748
Nanorods of the photomagnetic coordination network Mo(CN)8Cu2 coated with polyvinylpyrrolidone were prepared and exhibit an enhanced effect upon irradiation when compared to the bulk. 相似文献
48.
49.
Single‐Molecule Magnet Behavior of Individual Polyoxometalate Molecules Incorporated within Biopolymer or Metal–Organic Framework Matrices 下载免费PDF全文
Dr. Eric Rivière Shu Yang Dr. Catherine Roch‐Marchal Dr. Anne Dolbecq Dr. Corine Simonnet‐Jégat Prof. Nathalie Steunou Dr. Nathalie Leclerc‐Laronze Prof. Laurent Ruhlmann Prof. Talal Mallah Dr. Wolfgang Wernsdorfer Prof. Pierre Mialane 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6564-6574
The chemically and structurally highly stable polyoxometalate (POM) single‐molecule magnet (SMM) [(FeW9O34)2Fe4(H2O)2]10? (Fe6W18) has been incorporated by direct or post‐synthetic approaches into a biopolymer gelatin (Gel) matrix and two crystalline metal–organic frameworks (MOFs), including one diamagnetic (UiO‐67) and one magnetic (MIL‐101(Cr)). Integrity of the POM in the Fe6W18@Gel, Fe6W18@UiO‐67 and Fe6W18@MIL‐101(Cr) composites was confirmed by a set of complementary techniques. Magnetic studies indicate that the POMs are magnetically well isolated. Remarkably, in Fe6W18@Gel, the SMM properties of the embedded molecules are close to those of the crystals, with clear quantum tunneling steps in the hysteresis loops. For the Fe6W18@UiO‐67 composite, the molecules retain their SMM properties, the energy barrier being slightly reduced in comparison to the crystalline material and the molecules exhibiting a tunneling rate of magnetization significantly faster than for Fe6W18@Gel. When Fe6W18 is introduced into MIL‐101(Cr), the width of the hysteresis loops is drastically reduced and the quantum tunneling steps are smeared out because of the magnetic interactions between the antiferromagnetic matrix and the SMM guest molecules. 相似文献
50.
The transition from stratified to dual continuous oil–water flow (where each phase retains its continuity but there is dispersion of one phase into the other) as well as the dispersed phase fractions in the layers of the dual continuous pattern, were studied experimentally. Transition to this pattern from stratified flow occurs when drops of one phase appear into the other (onset of entrainment). The studies were carried out in a 38 mm ID horizontal stainless steel test section using two different inlet geometries, a T- and a Y-junction. The patterns were visualized through a transparent acrylic section located at 7 m from the inlet using a high speed video camera. Phase distribution measurements in a pipe cross section were obtained just before the acrylic section with a local impedance probe and the results were used to calculate the volume fraction of each phase entrained into the other. The onset of entrainment was found to occur at lower superficial water velocities as the oil superficial velocities increased. However, the inlet geometry did not affect significantly the transition line. During dual continuous flow, the dispersion of one phase into the opposite was found to extend further away from the interface with increasing water superficial velocity for a certain oil superficial velocity. An increase in the superficial water velocity increased the entrained fraction of water in oil (Ew/o) but there was no trend with the oil velocity. Similarly, an increase in the superficial oil velocity increased the fraction of oil drops in water (Eo/w) but the water velocity had no clear effect. The entrainment fractions were affected by the inlet geometry, with the T-inlet resulting in higher entrainment than the Y-inlet, perhaps because of the increased mixing induced by the T-inlet. The difference between the two inlets increased as the oil and water velocities increased. 相似文献