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81.
通过双吡唑甲基锂(LiCHPz2)与有机锡卤化物(R3SnX)的反应合成了一系列有机锡修饰的双吡唑甲烷配体(R3SnCHPz2).由于锡上取代基的不同,这些配体与W(CO)5THF反应时表现出了不同的反应方式.三芳基锡修饰的双吡唑甲烷与W(CO)5THF反应发生Sn-C(sp3)键对W(0)中心的氧化加成;而三苄基锡修饰的双吡唑甲烷与其反应时仅给出羰基取代产物[Bz3SnCHPz2W(CO)4].另外,二苯基苄基锡以及三(2-苯基-2-甲基丙基)锡修饰的双吡唑甲烷配体类似的反应导致配体的分解,产生单吡唑配体取代的羰基钨衍生物[W(CO)5PzH]以及脱有机锡的双吡唑甲烷四羰基钨衍生物[CH2Pz2W(CO)4]. 相似文献
82.
Butyltin concentrations have been measured at eight freshwater sites (rivers and lakes) in the Norfolk Broads, UK, during 1986 and 1987. Tributyltin (TBT) was found in water samples from seven of the sites. Wherever TBT was present, dibutyltin and (usually) monobutyltin occurred. Levels of TBT exceeded 100 ng dm?3 in open stretches of both the Rivers Bure and Yare in 1986 and 1987. The highest concentration of TBT recorded for Wroxham Broad (a shallow lake) was 898 ng dm?3. Values of up to 3.26 μg dm?3 were measured in water samples taken from a marina. A depth profile for Wroxham Broad showed TBT to be uniformly distributed throughout the shallow water column. The results are discussed in relation to toxicity of TBT to freshwater organisms. Laboratory measurements of the degradation of TBT in freshwater from a marina gave a half-life of six days at 20°C in the light. 相似文献
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13C NMR spectra for the 1:1 complex between methyl N-benzoyl-l-leucyl-l-histidinate and the trimethyltin moiety in d-chloroform (CDC13), d4-methanol (CD3OD) dimethyl sulphoxide (DMSO) and d6-DMSO/H2O solvents are reported, and contrasted with those for the free ligand. The spectra are interpreted in terms of a variety of solution equilibria illustrating the nature of the interaction between the trimethyltin species and primarily the imidazole ring of the histidine residue. Evidence for the preferential stability of pentacoordinate solution structures about tin is presented. 相似文献
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87.
《印度化学会志》2023,100(3):100945
The new dibutyltin(IV) complexes of Schiff bases is designed & synthesis from the interaction between various substituted amines and aromatic aldehyde with general formula Bu2Sn(L1-7)2Cl2. Where L1: (E)-4-chloro-N-(thiophen-2-ylmethylene) aniline; L2: (E)-2-chloro-N-(3,4,5-trimethoxybenzylidene) aniline; L3: (E)-N-((1H-indol-3-yl) methylene)-4-chloro-2-nitroaniline; L4: (E)-4-nitro-N-(3,4,5-trimethoxybenzylidene) aniline; L5: (E)-N-(3,4,5-trimethoxybenzylidene) aniline; L6: (E)-4-nitro-N-(thiophen-3-ylmethylene) aniline; L7: (E)-4-chloro-2-nitro-N-(pyridin-3-ylmethylene) aniline. Analytical and spectroscopic methods, such as molar conductance measurement, UV–Vis, IR, NMR, and DFT studies, have been used to describe newly synthesised compounds. The DFT studies have also provided confirmation regarding the complexes' geometry. The results of the Tauc equation indicate that the fundamental band gap of the compound [Bu2Sn(L5)2Cl2] is 2.670 eV, which is in agreement with the findings of DFT studies, which indicate that the band gap is 2.657 eV. The bactericidal effects of Schiff bases and their dibutyltin(IV) complexes were tested. The antibacterial activity of organotin(IV) complexes is enhanced in comparison to that of the free ligands. 相似文献
88.
Muhammad Mumtaz Anne de Cuendias Jean‐Luc Putaux Eric Cloutet Henri Cramail 《Macromolecular rapid communications》2006,27(17):1446-1453
Summary: The synthesis of PEDOT nanoparticles and vesicles by dispersion polymerization in a methanol/water mixture (3/2, v/v) is reported, using either ammonium persulfate or iron(III) p‐toluenesulfonate as oxidants and α‐EDOT‐PEO as a reactive stabilizer. The influence of the oxidant as well as the α‐EDOT‐PEO molar mass and concentration on the core‐shell particle morphology and conductivity properties have been investigated. PEDOT particles with conductivities up to 1.5 × 10−2 S · cm−1 have been obtained in high yield.
89.
IntroductionInrecentyears,thepharmaceuticalchemistryofpolyoxometallates(POMs)hasattract-edmuchattention[1,2].Inordertodevelopmorehighlyeffective,lowtoxicantiviralandanti-tumoralagents,attemptshavebeenmadetomodifythewell-knownKegginanions[Xn-W12O40](8… 相似文献
90.
Triorganotin halides, oxides and sulphides can be dissolved in molten, mixed-metal acetates at ca 140–160°C without decomposition; quenching provides glasses into which are encapsulated the organotin species. Halide/acetate and oxide/acetate, but not sulphide/acetate, exchanges occur in the melt. Only partial exchange was found for hindered trineophyl tin chloride [(PhCMe2CH2)3SnCl], in contrast to the complete exchanges observed for the butyl (Bu), phenyl (Ph) and cyclohexyl (Cy) analogues. Complete oxide/acetate exchange was found for (Bu3Sn)2O, partial exchange occurred for (Cy3Sn)2O, whilst no exchange resulted with bis(trineophyltin) oxide or (Ph3Sn)2O. Tin–tin bonds (e.g. as in Ph3SnSnPh3) and carbon–tin bonds (even the allyl–Sn bond in Bu3SnCH2CH?CH2) are not affected. The acetate glasses dissolve in aqueous media with release of the organotin species and they have potential as slow-release systems which is currently being investigated. 相似文献