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31.
Fuzzy linear programs with trapezoidal fuzzy numbers   总被引:1,自引:0,他引:1  
The objective of this paper is to deal with a kind of fuzzy linear programming problem involving symmetric trapezoidal fuzzy numbers. Some important and interesting results are obtained which in turn lead to a solution of fuzzy linear programming problems without converting them to crisp linear programming problems.  相似文献   
32.
In the present study, the hydroxyl groups at the C4 and C7 positions of sialic acid and C6 position of galactose in Neu5Acα(2–3)Gal (N23G) and the hydroxyl groups at the C8 position of sialic acid and C3 and C4 positions of galactose in Neu5Acα(2–6)Gal (N26G) were substituted with fluorine atoms, respectively. Molecular dynamics simulations of 100 ns duration were carried out to investigate the structural and dynamical behavior of H1 bound with the tri-fluorinated N23G and N26G (FN23G and FN26G). Based on energy analysis, it was concluded that FN26G should be a better binder for hemagglutinin (H1) than FN23G and it might act as an inhibitor for influenza.  相似文献   
33.
Three new bivalent nickel hydrazone complexes have been synthesised from the reactions of [NiCl(2)(PPh(3))(2)] with H(2)L {L = dianion of the hydrazones derived from the condensation of o-hydroxynaphthaldehyde with furoic acid hydrazide (H(2)L(1)) (1)/thiophene-2-acid hydrazide (H(2)L(2)) (2)/isonicotinic acid hydrazide (H(2)L(3)) (3)} and formulated as [Ni(L(1))(PPh(3))] (4), [Ni(L(2))(PPh(3))] (5) and [Ni(L(3))(PPh(3))] (6). Structural characterization of these compounds 4-6 were accomplished by using various physico-chemical techniques. Single crystal X-ray diffraction data of complexes 4 and 5 proved their distorted square planar geometry. In order to ascertain the potential of the above synthesised compounds towards biomolecular interactions, additional experiments involving interaction with calf thymus DNA (CT DNA) and bovine serum albumin (BSA) were carried out. All the ligands and corresponding nickel(ii) chelates have been screened for their scavenging effect towards O(2)(-), OH and NO radicals. The efficiency of complexes 4-6 to arrest the growth of HeLa, HepG-2 and A431 tumour cell lines has been studied along with the cell viability test against the non-cancerous NIH 3T3 cells under in vitro conditions.  相似文献   
34.
A new series of new hetero-bimetallic complexes containing iron and ruthenium of the general formula [RuCl(CO)(B)(EPh3)(L)] (where E=P or As; B=PPh3, AsPh3, py or pip; L=ferrocene derived monobasic bidentate thiosemicarbazone ligand) have been synthesized by the reaction between ferrocene-derived thiosemicarbazones and ruthenium(II) complexes of the type [RuHCl(CO)(B)(EPh3)2] (where E=P or As; B=PPh3, AsPh3, py or pip). The new complexes have been characterized by elemental analyses, IR, electronic, NMR (1H, 13C and 31P), EXAFS (extended X-ray absorption fine structure spectroscopy) and cyclic voltammetric techniques. Antibacterial activity of the new complexes has been screened against Escherichia coli, Vibrio cholerae, and Pseudomonas aeruginosa species.  相似文献   
35.
Nanoparticles provide an attractive route to modifying polymer thin film properties, yet controlling the dispersion and morphology of functionalized nanoparticle filled films is often difficult. Block copolymers can provide an ideal template for directed assembly of nanoparticles under controlled nanoparticle‐polymer interactions. Previously we observed that neat films of cylinder forming poly(styrene‐b‐methyl methacrylate) PS‐b‐PMMA block copolymer (c‐BCP) orient vertically with dynamic sharp thermal cold zone annealing (CZA‐S) over wide range of CZA‐S speed (0.1–10) μm/s. Here, we introduce a low concentration (1–5 wt %) of nanoparticles of phenolic group functionalized CdS (fCdS‐NP), to PMMA cylinder forming polystyrene‐b‐poly (methyl methacrylate) block copolymer (c‐BCP) films. Addition of the fCdS‐NP induces a vertical to horizontal orientation transition at low CZA‐S speed, V = 5 μm/s. The orientation flip studies were analyzed using AFM and GISAXS. These results confirm generality of our previously observed orientation transition in c‐BCP under low speed CZA‐S with other nanoparticles (gold [Au‐NP], fulleropyrrolidine [NCPF‐NP]) in the same concentration range, but reveal new aspects not previously examined: (1) A novel observation of significant vertical order recovery from 5–10% vertical cylindrical fraction at V = 5 μm/s to 46–63% vertical cylindrical fraction occurring at high CZA‐S speed, V = 10 μm/s for the fCdS nanoparticle filled films. (2) We rule out the possibility that a nanoparticle wetting layer on the substrate is responsible for the vertical to horizontal flipping transition. (3) We demonstrate that the orientation flipping results can be achieved in a nanoparticle block copolymer system where the nanoparticles are apparently better‐dispersed within only one (matrix PS) domain unlike our previous nanoparticle system studied. We consider facile processing conditions to fabricate functionalized nanoparticles filled PS‐PMMA block copolymer films with controlled anisotropy, a useful strategy in the design of next generation electronic and photonic materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 604–614  相似文献   
36.
Binuclear ruthenium(III) complexes containing a binucleating Schiff base ligand, L and Ph3P or Ph3As, [RuX2(EPh3)2]2L (X = Cl or Br; E = P or As) have been prepared by reacting [RuCl3(PPh3)3], [RuCl3(AsPh3)3], [RuBr3(AsPh3)3] and [RuBr3(PPh3)2(MeOH)] with Schiff bases in a 2:1 molar ratio. The Schiff bases used in this study were prepared by condensing the appropriate diamine with salicylaldehyde or benzoylacetone in a 1:2 molar ratio respectively. The complexes were characterised by analytical, spectral (i.r., electronic, e.p.r.) and electrochemical data. An octahedral structure has been proposed for all the new ligand-bridged binuclear RuIII complexes. The new complexes have been used as catalysts in aryl–aryl couplings and also subjected to antifungal activity studies.  相似文献   
37.
Summary: Nanocomposites were formulated by curing a sonicated mixture of epoxy resin, C18 clay, and acrylic rubber dispersants. At 5.5 phr (parts per hundred) organoclay loading and a rubber concentration of 15 phr, the tensile‐failure strain of the nanocomposite was found to be higher than that of epoxy nanocomposite, rubber‐dispersed epoxy, and pristine epoxy. A plausible mechanism for improvement of the failure strain of nanocomposites is proposed.

Stress strain curves of filled and unfilled epoxy specimen.  相似文献   

38.
Ruthenium(II) carbonyl complexes of general formula [Ru(CO)(B)(L)] [where B = PPh3, pyridine (py), piperidine (pip); L = the dianionic tetradentate Schiff bases derived from the condensation of acetylacetone or benzoylacetone with ethylenediamine, propylenediamine or trimethylenediamine] have been synthesised by reacting [RuHCl(CO)(PPh3)2(B)] (B = PPh3, py or pip) with bis(acetylacetone)ethylenediimine, bis(acetylacetone)propylenediimine, bis(acetylacetone)trimethylenedi- imine, bis(benzoylacetone)ethylenediimine, bis(benzoylacetone)propylenediimine or bis(benzoylacetone)trimethylenediimine. The complexes were characterised onthe basis of elemental analyses, i.r., electronic and 1H- and 31P{1H}-n.m.r. spectral studies. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
39.
40.
The objective of the study is to formulate exclusive block copolymer (BCP) nanocomposites by dispersing bcp end‐grafted nanoparticles (bcp‐g‐nps) of PMMA‐b‐PS‐g‐TiO2 within PS‐b‐PMMA matrix. PMMA‐b‐PS‐g‐TiO2 is synthesized using a “grafting‐to” approach and characterized by XPS and TGA to establish that the copolymer chains were bonded to NPs. Good dispersion of bcp‐g‐nps in PMMA and PS‐PMMA bcp films is observed, in contrast to poor dispersion in PS films. In PS‐PMMA films, the compatible and identical bcp nature of the end‐grafted polymer, and large NP size caused it to span across entire PS‐PMMA domains. Poor and good dispersion in PS and PMMA matrices, respectively, can be rationalized by the fact that NPs interactions are driven by the PMMA at the outer corona of the bcp‐g‐nps. Developing bcp‐g‐nps as a strategic route to preparation of highly dispersed high permittivity NPs like titanium dioxide (TiO2) in bcp matrix can have important ramifications for energy storage devices. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 468–478  相似文献   
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