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101.
Hasan Karabıyık M. Emin Günay Muhittin Aygün Bekir Çetinkaya Canan Kazak 《Journal of chemical crystallography》2006,36(4):243-248
The molecular and crystal structures of the title compound, C19H22N2O4S, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in space group F d d 2, with a = 30.785(3) ?, b = 10.6455(9) ?, c = 11.0036(8) ?, Z = 8, D
calc = 1.379(2) g cm−3, μ(Mo-Kα) = 0.207 mm−1, and its crystal system is orthorhombic. The structure was solved by direct methods and refined to a final R = 0.042 for 1530 reflections with I > 2σ (I). There is a half-independent molecule in the asymmetric unit. The title molecule has twofold rotational symmetry along with the C–S bond. Classically no hydrogen bond is found in the crystal structure. The crystal structure is stabilized by π–π stacking and edge to face (C–H…π-ring) interactions. To elucidate conformational features and steric hindrances of the title molecule, selected torsion angle is varied from −180° to +180° in every 10° and thus molecular energy profile is calculated by PM3 semi-empirical method.Supplementary materials CCDC 261789 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge CB2 1EZ, UK; fax: $+$44 1223 336033. 相似文献
102.
103.
超声波振动台内含压电材料,可以拾取切削过程产生的振动信号,实现不借助外部传感器刀具工作状态的自感知。为了从刀具振动信号中获取有效信息,该文提出一种基于经验模态分解的时频域重构算法。首先,采用经验模态分解算法将原始信号分解,得到多个固有模态函数分量和残差分量;其次,计算原始信号与各分量之间的时频域互相关系数;再次,归一化时频域互相关系数作为权重值,将固有模态函数分量和残差进行重构;最后,通过数值仿真和超声辅助加工实验,验证了基于经验模态分解的时频域重构算法的去噪性能,提取了信噪比为5.03 dB的目标信号,从而实现了超声辅助加工系统的自感知功能。 相似文献
104.
Melis Bayraktaroğlu Hande Orhan Sinem Evli Sinan Akgöl Deniz Aktaş Uygun 《Journal of carbohydrate chemistry》2013,32(5):302-317
AbstractPreparation of poly[ethylene glycol dimethacrylate (EGDMA)-glycidyl methacrylate (GMA)] cryogel and its usability for amyloglucosidase adsorption were investigated. Cryogels were prepared by cryocopolymerization technique and then functionalized by lectin concanavalin A (Con A). The synthesized cryogel was characterized by FTIR, SEM and EDX analysis and then used for adsorption of amyloglucosidase in a continuous flow system. The maximal amyloglucosidase adsorption efficiency of Con A attached cryogel was found to be as 30.50?mg/g cryogel. Con A modified cryogels were used repeatedly for 30 times without any significant decrease at the amyloglucosidase adsorption capacity. SDS-PAGE and activity studies confirmed that the desorbed amyloglucosidase was active and retained 90% of its initial activity after the adsorption/desorption processes. 相似文献
105.
106.
The new vicinal dioxime N,N-bis(2-benzimidazolylmethyl)diaminoglyoxime (H2L) has been prepared by reacting 2-aminomethylbenzimidazole with cyanogen-di-N-oxide. Reaction of H2L with CuII and CoIII salts and appropriate reagents gave mono- and trinuclear complexes, [Cu(HL)2], [Cu3(L)2(phen)2], [Co(HL)2LCl] (L=2,6-lutidine), [Co(LBF2)2LCl] and [Cu2(ClO4)2Co(LBF2)2LCl](ClO4)2, which were characterized by i.r., 1H- and13 C-n.m.r., m.s. and elemental analyses. 相似文献
107.
This article describes the synthesis of a new (2E,3E,6R,9E,11E)-6-isopropenyl-3,6,10-trimethyl-5,8-dioxa-4,9-diazadodeca-3,9-diene-2,11-dione dioxime (H2hmdm), and its mono-, homo, and heterodinuclear copper(II)/nickel(II) complexes. Elemental analyses, stoichiometric and spectroscopic
data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). The
Cu(H2hmdm), molecule coordinates to the second copper(II) ion through the oximate oxygens to afford a binuclear structure doubly
bridged by the oximate groups in the cis arrangement. In the dinuclear complexes, in which the first CuII ion was complexed with nitrogen atoms of the oxime and imine groups, the second CuII ion is ligated with the 1,10-phenanthroline nitrogen atoms. Ligand and its mononuclear copper(II), homo and heterodinuclear
copper(II)–nickel(II) complexes of (H2hmdm) were characterized by elemental analyses, magnetic moments, 1H-n.m.r. and 13C-n.m.r., i.r., and mass spectral studies. The data support the proposed structure of H2hmdm and its complexes. 相似文献
108.
A new ligand incorporating a dioxime moiety, (2E,3E)-3-[(2-{[(1E,2E)-2-(hydroxyimino)-1-methylpropylidene]amino}phenyl)imino]butan-2-one oxime, (H2Phmdo) (3) has been prepared by reacting 2,3-butanedionemono-{O-[4-(1-methyl-2-oxo-propylideneaminooxy)-2,3-bis-(1-methyl-2-oxo-propylideneaminooxy-methyl)-but-2-enyl]-oxime} (2) with 1,2-phenylenediamine. Mono-, di- and trinuclear copper(II) and/or nickel(II) complexes of H2Phmdo were characterized by elemental analyses, magnetic moments, 1H-n.m.r. and 13C-n.m.r., i.r. and mass spectral studies. The mononuclear copper(II) and nickel(II) complexes of H2Phmdo were found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal
complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). In the dinuclear complexes,
in which the first Cu(II) or Ni(II) ion was complexed with nitrogen atoms of the oxime and imine groups, the second Cu(II) ion is ligated with dianionic oxygen atoms of the oxime groups and are linked to the 1,10-phenanthroline nitrogen atoms.
The data support the proposed structure of H2Phmdo and its complexes. 相似文献
109.
The -radiolysis of Methyl Red solution in HCl medium at pH=2 has been studied along with energy transfer reaction brought about byF and hole centers of -irradiated NaCl. The G-values for degradation of the azo dye indicator by radiolysis and -irradiated salt were determined as 9·10–1 and 4.8·10–3, respectively. The kinetic rate constants (k) of degradation are evaluated as 2·10–5 rad–1 in the case of direct radiolysis, while for the irradiated salt it is 2·10–7 rad–1. The extent of degradation by direct -radiolysis is 100–200 times greater as compared to that by the -irradiated salt. The same mechanism is proposed for radiolysis as well as the reaction induced by -irradiated sodium chloride. 相似文献
110.
Sevil DinçerVolkan Köseli Hande KesimZakir M.O Rzaev Erhan Pi?kin 《European Polymer Journal》2002,38(11):2143-2152
Radical-initiated copolymerization of N-isopropylacrylamide (NIPA) with maleic (MA) and citraconic (CA) anhydrides was carried out in the presence of 2,2′-azobisisobutyronitrile (AIBN) as an initiator in 1,4-dioxane at 65 °C under nitrogen atmosphere. Structure and monomer unit compositon of the copolymers obtained from a wide range of monomer feed were determined by elemental analysis (content of N for NIPA units), Fourier transform infrared and 1H NMR spectroscopy. Monomer reactivity ratios for NIPA (M1)-MA (M2) and NIPA (M1)-CA (M2) pairs were determined by Kelen-Tüdõs (KT) and non-linear regression (NLR) methods using elemental and 1H NMR spectroscopy analyses data. They are r1=0.45 and r2=0.08 (KT, N analysis), r1=0.44 and r2=0.10 (KT, 1H NMR), r1=0.45 and r2=0.078 (NLR) for NIPA-MA monomer pair and r1=0.52 and r2=0.02, r1=0.44 and r2=0.04, r1=0.51 and r2=0.014 for NIPA-CA monomer pair, respectively. Observed tendency towards alternating copolymerization at ?50 mol% NIPA concentration in monomer feed and relatively high activity of NIPA growing radical was explained by H-bond formation between CO (anhydride) and NH (amide) fragments during chain growth reactions. Intrinsic viscosity, molecular weight and thermal behaviour of the synthesized copolymers were found to depend on the type of comonomer and the amount of NIPA units in the copolymers. These functional amphiphilic copolymers containing anion- and cation-active groups show both temperature and pH sensitivity and can be used for biological purposes as physiologically active macromolecular systems. 相似文献