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51.
One novel polyoxometalate compound connected via trivalent cerium cation as bridge H2{[K(H2O)2]2[Ce(H2O)5]2(H2Mo1.16W10.84O42)}·8H2O 1 was designed and synthesized in aqueous solution. X-ray diffraction analysis reveals that the structure of 1 is a three-dimensional framework assembled from the arrangement of H2Mo1.16W10.84O42 (named paradodecmetalate-B) and Ce(H2O)53 containing two planes, which are constructed through the unification of H2Mo1.16W10.84O4210- and Ce(H2O)53 along the [100] and [001] directions. Crystal data: H96Ce4K4Mo2.32O128W21.68, Mr = 7074.89, monoclinic, P21/n, a = 12.5037(17), b = 17.002(2), c = 12.7473(17) (A), β = 105.966(2)°, V = 2605.4(6) (A)3, Z = 1, Dc = 4.509 g/cm3, F(000) = 3132, μ = 26.098 mm(1, R = 0.0377 and wR = 0.0789 (I > 2σ(I)).  相似文献   
52.
The title compound [Mn(O2CMe)2(phen)2] (phen = 1,10-phenanthroline) 1 has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group Pbcn, with a = 12.554(4), b = 10.168(3), c = 17.704(5) (A), V = 2259.7(12) (A)3, Z = 4, C28H22MnN4O4, Mr = 533.44, Dc = 1.568 g/cm3, F(000) = 1100, Rint = 0.0242, T = 293(2) K and μ = 0.631 mm-1. The final R = 0.0687 and wR = 0.1960 for 2046 observed reflections with I > 2σ(I). The structure of the complex consists of one Mn(Ⅱ) core coordinated by two bidentate-bound CH3COO- groups and two η2-phen groups forming an eight-coordinate geometrical configuration.  相似文献   
53.
5-O-Benzoyl-1,2-O-isopropylidene-α-D-erythro-ketofuranose-3-ulose-3-aminothiose 3 was synthesized and characterized by spectral analysis, and its crystal structure was determined by X-ray diffraction analysis. The crystal belongs to orthorhombic, space group P212121 with a = 6.6276(13), b = 10.993(2), c = 25.027(5) , β = 90°, V = 1823.4(6)3, Z = 4, C16H20N3O5S, Mr = 366.41, Dc = 1.335 g/cm3, μ = 0.208 mm-1, F(000) = 772, S = 1.007, the final R = 0.0465 and wR = 0.1061 for 3251 observed reflections (I > 2σ(I)). Four hydrogen bonds are observed. The absolute configuration of this molecule was confirmed by comparing with that of the original material.  相似文献   
54.
A novel one-dimensional chain-like coordination polymer constructed from 3-nitrobenzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) (A), β = 95.608(2)°, V= 1111.6(2)(A)3, Mr =751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692for 2338 observed reflections with I > 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(CsH3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the tifle compound has been also discussed in this paper.  相似文献   
55.
IntroductionOrganometallicandcoordinationcomplexeshavere centlyemergedaspotentialbuildingblocksfornonlinearoptical (NLO )materials .1 6Comparedwithorganicmolecules ,metalcomplexescanhavealargervarietyofstructuresandamuchgreaterdiversityoftunableelec tronic…  相似文献   
56.
A new nickel(Ⅱ) coordination complex [Ni(phen)3]·(m-nitrobenzoic acid)2·(H2O) was synthesized by self-assembly of m-nitrobenzoic acid, 1,10-phenanthroline and nickelous perchlorate. It crystallizes in the monoclinic system, space group C2/c, with a = 2.4596(6), b = 1.2124(3), c = 1.9824(5) nm, β = 97.088(5)°, V = 5.866(3) nm3, Dc = 1.474 g/cm3, Z = 4, Mr = 1301.82, μ(MoKα) = 0.417 mm-1 F(000) = 2688, R = 0.0493 and wR = 0.1025. Structural determination indicates that the nickel(Ⅱ) ion is coordinated with six nitrogen atoms from three phens, giving a distorted octahedral coordination geometry. The cyclic voltametric analysis shows that the electron transfer in the electrode reaction is irreversible.  相似文献   
57.
The title compound S-( )-N'-tertbutylaminocarbonyl-N-[3-methyl-2-(4-chlorophenyl)butyryl] thiourea has been synthesized and its crystal structure was determined by singlecrystal X-ray diffraction an alysis. There exist intramolecular N(2)-H(2A)… O(1), C(17)-H(17A)…O(2) and N(3)-H(3A)…S(1) hydrogen bonds as well as intermolecular N-H…O interaction between the carbonyl and amidogen groups. Crystallographic data: C17H24ClN3O2S, Mr = 369.90,monoclinic, space group C2/c with a = 22.9922(19), b = 14.4844(12), c = 12.4618(11) (A),β =92.608(2)°, V= 4145.8(6) (A)3, Z = 8, Dc = 1.185 g/cm3, F(000) = 1568,μ(MoKa) = 0.298 mm-1, R =0.0578 and wR = 0.1308.  相似文献   
58.
Conjugate polymers provide the possibility of exploiting both the chemical and physical attributes of the polymers for membrane-based gas separation. The presence of delocalized π electrons provides high chain stiffness with low packing density, thus making the membrane a rigid structure that favors facilitated transport. Historically, the polymeric membranes were constrained by the tradeoff relationship between gas permeability and gas selectivity. So, different methods were investigated to prepare the membranes that can overcome the limitation. In recent years, electroconductive polymeric membranes have gained attention with their enhanced transportation properties combining the separation behavior depending on both molecular size discrimination as well as the facilitated transport. They offer better selectivity toward polar gases such as CO2 because of the increased solubility. This review is aimed to provide a literature survey on gas separation using conjugate polymers such as polyaniline, polypyrrole, and some derivatives of polythiophenes. It contains various methods used by different researchers to enhance the gas separation properties of the membranes with improved mechanical and thermal stability such as changing the morphology and membrane preparation methods. In addition, it provides the pros and cons of various factors affecting the conjugate polymer membrane performance. The major challenges and future work that can be done in improving the transportation properties through the membrane to achieve viable membranes are also discussed so that they can be used for commercial and practical applications in the future.  相似文献   
59.
The title compound {[Cu4(OH)4(2,2'-bpy)4(bqdc)]·2ClO4}n 1 (bqdc = 2,2'-biquinoline-4,4'-dicarboxylic acid) has been synthesized by hydrothermal method. Its crystal structure is of triclinic, space group P-1 with a = 7.6561(5), b = 12.4652(8), c = 15.7501(10) (A), α= 80.0480(10), β= 87.7900(10), γ = 74.0800(1)°, V = 1423.65(16) (A)3, Z = 2, C30H23ClN5O8Cu2, Mr = 744.06, Dc = 1.736 g/cm3, μ = 1.651 mm-1, F(000) = 754, the final R = 0.0421 and wR = 0.1163 for 4973 observed reflections with Ⅰ> 2σ(Ⅰ). In 1, tetra-copper chair-like clusters of [Cu4(OH)4(2,2'-bpy)4]4 are connected by bqdc ligands to form one-dimensional chains, which are further connected by hydrogen bonds to generate a two-dimensional supramolecular network .  相似文献   
60.
Two nickel coordination polymers [Ni(H2O)(C4H4O5)]·H2O 1 and [Ni(H2O)(mal)(phen)] 2, have been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. Crystal data for 1: C4H8O7Ni, monoclinic Cc, , , , , Z=4. Crystal data for 2: C16H14N2O6Ni, orthorhombic Pna21, , , , Z=4. Compound 1 is constructed from [Ni(H2O)(C4H4O5)] sheets pillared through β-carboxylate groups into a 3D framework, which exhibits a diamond-like network. Compound 2 exhibits a 3D supramolecular network. To our knowledge, compound 1 represents the first diamond-like topology in the system of metal-malate. Other characterizations by elemental analysis, IR and TG are also described. The magnetic behavior of compound 1 has been studied.  相似文献   
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