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41.
A novel organic-inorganic hybrid compound constructed from mixed ligands, Co3(SIP)2(bipy)4(H2O)6·6.5H2O (H3SIP = 5-sulfoisophthalic acid, bipy = 4,4′-bipyridyl), has been hydrothermally synthesized and characterized by IR, TGA and single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group P212121 with a = 11.395(2), b = 19.395(4), c = 30.675(6) A^°, Mr = 1513.05, V= 6779(2) A^°^3, Dc= 1.482 g/cm^3, F(000) = 3120, μ = 0.873 mm^-1, Z= 4, the final R = 0.0439 and wR = 0.119 for 13421 observed reflections with I〉 2σ(I). The structure of the compound presents a 3-D framework containing Co-bipy 1-D chain and 2-D bilayer motifs and carboxylate spacers, and the connection of 1-D chain and 2-D bilayer motifs by carboxylate ligand results in the final open framework with twofold interpenetration net. A probe reaction of the oxidation of benzaldehyde with H2O2 using the title compound as catalyst was carded out in a liquid-solid system, showing that the compound has high oxidative catalytic activity to the reaction.  相似文献   
42.
The validity of single-fluid model in inertial confinement fusion simulations is studied by comparing the results of the multi- and single-fluid models. The multi-fluid model includes the effects of collision and interpenetration between fluid species. By simulating the collision of fluid species, steady-state shock propagation into the thin DT gas and expansion of hohlraum Au wall heated by lasers, the results show that the validity of single-fluid model is strongly dependent on the ratio of the characteristic length of the simulated system to the particle mean free path. When the characteristic length L is one order larger than the mean free path A, the single-fluid model's results are found to be in good agreement with the multi-fluid model's simulations, and the modeling of single-fluid remains valid. If the value of L/A is lower than 10, the interpenetration between fluid species is significant, and the single-fluid simulations show some unphysical results; while the multi-fluid model can describe well the interpenetration and mix phenomena, and give more reasonable results.  相似文献   
43.
This article systematically investigates the influence of the properties of inhomogeneous N‐auxiliary ligands and pH value on the helical structures of complexes based on C2‐symmetric ligand 1,3‐adamantanedicarboxylic acid (H2ADC). Five kinds of neutral ligands (phen=1,10‐phenanthroline, bipy=4,4′‐bipyridine, bpa=1,2‐bis(4‐pyridyl)ethane, bpe=1,2‐bis(4‐pyridyl)ethane, and bpp=1,3‐bis(4‐pyridyl)propane) were selected, and a series of new ZnII/CoII dicarboxylates have been synthesized by slow diffusion, namely, [Zn(phen)(ADC)(H2O)]2 ? CH3OH ( 1 ), {[Zn(ADC)(bpe)] ? H2O}n ( 2 ), {[Zn(ADC)(bipy)] ? 2 H2O}n ( 3 ), {[Zn(ADC)(bpa)]2 ? 5 H2O}n ( 4 ), {[Zn(ADC)(bpp)]2 ? CH3OH}n ( 5 ), {[Zn(ADC)(bpp)]}n ( 6 ), {[Co(ADC)(bpp)(CH3OH)(H2O)] ? CH3OH ? 2 H2O}n ( 7 ), and {[Co(ADC)(bpp)]}n ( 8 ). Single‐crystal X‐ray structural analysis shows that complex 1 forms a 0D dinuclear with closed‐loop unit. The complex 2 is a 2D layer framework. Compounds 3 and 4 are isomorphous with a small discrepancy and present one‐dimensional chainlike structures. It is interesting that the 2D organic–inorganic hybrid frameworks containing meso‐helical chains have been observed. Compound 5 is a 2D interpenetrated network with (4,4) topology, in which homochiral left‐handed helical chains are arranged in an ABAB sequence parallel to the plane defined by (a,c), and right‐handed helical chains running along the a axis are also observed in the solid state, resulting in a meso‐helical structure. Compounds 6 , 7 , and 8 crystallize in a chiral space group P212121. Highly dimensional 6 and 8 are essentially isostructural and present a threefold interpenetrated 3D diamondoid network containing three helical chains, whereas 7 exhibits a 2D grid layer with a left‐handed helical chain. Furthermore, thermal stability, X‐ray powder diffraction, and the luminescent properties of 1 , 2 , 3 , 4 , 5 , 6 are also discussed.  相似文献   
44.
A new CoII coordination polymer with complicated topology, namely [Co(bpp)2Cl2]n (1) (bpp=1,3‐bis(4‐pyridyl)propane), has been designed and synthesized based on flexible ligand under basic condition. The complex was characterized by single‐crystal X‐ray analysis and infrared spectroscopy. The CoII ions are linked into a 3D structure via bpp molecules. Four independent frameworks are related by translation along the c tetragonal axis in the usual interpenetration topology for diamondoid frames. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
45.
Soft and responsive colloids based on polymer hydrogels have moved into the focus of the colloid community. This review gives a brief overview of the recent literature on the structure and phase behavior of neutral and ionic poly(N-isopropylacrylamide) microgel dispersions from dilute to over-packed conditions, focusing in particular on the ability of these particles to adapt their size and shape in response to external stimuli. The review is hierarchical; it first covers the aspects of an individual microgel particle viz., the internal structure of inhomogeneous and homogeneously cross-linked particles, followed by studies of ensembles of particles covering in particular structural ordering, phase behavior, and liquid–solid and solid–solid transitions. Insights on the ability of the microgel particles to deform, compress, and interpenetrate beyond the close-packed volume fractions are discussed. Building complex architectures using microgel particles for fundamental studies as well as future applications is reviewed towards the end of the article.  相似文献   
46.
GU  Jian-Fa YE  Wen-Hua 《理论物理通讯》2009,(12):1102-1106
The effects of atomic-level rnixing are systemically investigated in a multifluid interpenetration mix model ,and results are compared with the single-fluid model's simulations and experimental data. It is shown that increasing the model free parameter α, shock Mach number, and the initial density discontinuity makes the mix length and fraction of mixing particle increase, resulting in the lower shock temperatures compared with the results of single-fluid model without mixing. Recent high-compressibility direct-drive spherical implosions on OMEGA are simulated by the interpenetration mix modal. The calculations with atomic mixing between fuel and shell match quite well with the observations. Without considering any mixing, the calculated neutron yields and ion temperatures are overpredicted; while inclusion of the interpenetration mix model with the adjustable parameter α could fit the simulated neutron yields and ion temperatures well with experimental data.  相似文献   
47.
The 2‐methylbiphenyl‐4,4′‐dicarboxylate (mbpdc2−) ligand has versatile coordination modes and can be used to construct multinuclear structures. Despite this, reports of the synthesis of coordination complexes involving this ligand are scarce. The title compound, poly[[triaquadi‐μ3‐hydroxido‐hexakis(μ4‐2‐methylbiphenyl‐4,4′‐dicarboxylato)calcium(II)hexazinc(II)] monohydrate], {[CaZn6(C15H10O4)6(OH)2(H2O)3]·H2O}n , has been prepared by the hydrothermal assembly of Zn(NO3)2·6H2O, CaCl2 and 2‐methylbiphenyl‐4,4′‐dicarboxylic acid. Two ZnII atoms adopt a four‐coordinated distorted tetrahedral geometry by bonding to three O atoms from three different 2‐methylbiphenyl‐4,4′‐dicarboxylate (mbpdc2−) dianionic ligands and one bridging hydroxide O atom. For the remaining ZnII atom, a five‐coordinate environment is completed half the time by one carboxylate O atom, and then the same carboxylate O atom and an aqua O atom are present the other half of the time, giving a six‐coordinate environment. The CaII atom is coordinated by six O atoms to give an octahedral coordination geometry. The supramolecular secondary building unit (SBU) is a hamburger‐like heptanuclear unit (Zn6CaO30) and these units are interconnected through mbpdc2− carboxylate groups to generate a three‐dimensional framework with the pcu topology. The single net leaves voids that are filled by mutual interpenetration of an independent equivalent framework in a twofold interpenetrating architecture. The title compound shows thermal stability up to 673 K. The excitation and luminescence data showed the emission of a bright‐blue fluorescence.  相似文献   
48.
We propose a new two-fold integration transformation in p-q phase space ∫∫-∞(dp dq/π)e2i(p-x)(q-y)f(p,q)≡G( x,y), which possesses some well-behaved transformation properties. We apply this transformation to the Weyl ordering of operators, especially those Q-P ordered and P-Q ordered operators.  相似文献   
49.
汪快兵  王彦  陈友存 《结构化学》2009,28(5):590-596
A novel cadmium(Ⅱ) coordination polymer [Cd2(3-pa)4(4,4'-bpy)(H2O)].3.08H2O 1 has been synthesized by pyridine-3-carboxylate (3-pall) and CdO with exo-bidentate rigid dipyridyl ligand 4,4'-bipyridine (4,4'-bpy) by using a hydrothermal method, its structure was determined by single-crystal X-ray diffraction and its luminescent property was also documented. Complex 1 crystallizes in orthorhombic space group Pbcn with a = 21.4074(14), b = 27.1119(18), c = 12.3879(8) A, V = 7189.9(8) A3, Z = 8, C34H32.16Cd2N6O12.08, Mr= 942.85, Dc = 1.742 g/cms, p = 1.255 mm-1 and F(000) = 3766. The structure was solved by direct methods and refined to R = 0.0353 and wR = 0.0891 for 6278 observed reflections (I 〉 2σ(I)). The most prominent structural feature is the mutual interpenetration of two identical 3-D open frameworks via filling the large void space, which gives a 2-fold interpenetrating architecture during the self-assembly process.  相似文献   
50.
In metal–organic framework (MOF) chemistry, interpenetration greatly affects the gas‐sorption properties. However, there is a lack of a systematic study on how to control the interpenetration and whether the interpenetration enhances gas uptake capacities or not. Herein, we report an example of interpenetration that is simply controlled by the presence of a carbon–carbon double or single bond in identical organic building blocks, and provide a comparison of gas‐sorption properties for these similar frameworks, which differ only in their degree of interpenetration. Noninterpenetrated ( SNU‐70 ) and doubly interpenetrated ( SNU‐71 ) cubic nets were prepared by a solvothermal reaction of [Zn(NO3)2] ? 6 H2O in N,N‐diethylformamide (DEF) with 4‐(2‐carboxyvinyl)benzoic acid and 4‐(2‐carboxyethyl)benzoic acid, respectively. They have almost‐identical structures, but the noninterpenetrated framework has a much bigger pore size (ca. 9.0×9.0 Å) than the interpenetrated framework (ca. 2.5×2.5 Å). Activation of the MOFs by using supercritical CO2 gave SNU‐70′ and SNU‐71′ . The simulation of the PXRD pattern of SNU‐71′ indicates the rearrangement of the interpenetrated networks on guest removal, which increases pore size. SNU‐70′ has a Brunauer–Emmett–Teller (BET) surface area of 5290 m2 g?1, which is the highest value reported to date for a MOF with a cubic‐net structure, whereas SNU‐71′ has a BET surface area of 1770 m2 g?1. In general, noninterpenetrated SNU‐70′ exhibits much higher gas‐adsorption capacities than interpenetrated SNU‐71′ at high pressures, regardless of the temperature. However, at P<1 atm, the gas‐adsorption capacities for N2 at 77 K and CO2 at 195 K are higher for noninterpenetrated SNU‐70′ than for interpenetrated SNU‐71′ , but the capacities for H2 and CH4 are the opposite; SNU‐71′ has higher uptake capacities than SNU‐70′ due to the higher isosteric heat of gas adsorption that results from the smaller pores. In particular, SNU‐70′ has exceptionally high H2 and CO2 uptake capacities. By using a post‐synthetic method, the C?C double bond in SNU‐70 was quantitatively brominated at room temperature, and the MOF still showed very high porosity (BET surface area of 2285 m2 g?1).  相似文献   
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