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51.
Mitsuishi M Morita S Tawa K Nishii J Miyashita T 《Langmuir : the ACS journal of surfaces and colloids》2012,28(5):2313-2317
We present spontaneous emission control of a core-shell CdSe/ZnS nanoparticle array assembled with polymer ultrathin films consisting of polymer nanosheets on a silver grating substrate, which served as a unique and simple photonic cavity. The grating-coupled waveguide modes enabled 10(3) order luminescence enhancement and one-fourth spectral narrowing. The light emission from a CdSe/ZnS nanoparticle array can be controlled by tuning the film thickness of hybrid polymer nanoassemblies, which provides multiple emission performance with good tuning ability from red to green at low-power continuous wave laser excitation (~μW). 相似文献
52.
Sato K Ohnuki T Takahashi H Miyashita Y Nozaki K Kanamori K 《Inorganic chemistry》2012,51(9):5026-5036
Three novel tetranuclear vanadium(III) or (IV) complexes bridged by diphenyl phosphate or phosphate were prepared and their structures characterized by X-ray crystallography. The novel complexes are [{V(III)(2)(μ-hpnbpda)}(2){μ-(C(6)H(5)O)(2)PO(2)}(2)(μ-O)(2)]·6CH(3)OH (1), [{V(III)(2)(μ-tphpn)(μ-η(3)-HPO(4))}(2)(μ-η(4)-PO(4))](ClO(4))(3)·4.5H(2)O (2), and [{(V(IV)O)(2)(μ-tphpn)}(2)(μ-η(4)-PO(4))](ClO(4))(3)·H(2)O (3), where hpnbpda and tphpn are alkoxo-bridging dinucleating ligands. H(3)hpnbpda represents 2-hydroxypropane-1,3-diamino-N,N'-bis(2-pyridylmethyl)-N,N'-diacetic acid, and Htphpn represents N,N,N',N'-tetrakis(2-pyridylmethyl)-2-hydroxy-1,3-propanediamine. A dinuclear vanadium(IV) complex without a phosphate bridge, [(VO)(2)(μ-tphpn)(H(2)O)(2)](ClO(4))(3)·2H(2)O (4), was also prepared and structurally characterized for comparison. The vanadium(III) center in 1 adopts a hexacoordinate structure while that in 2 adopts a heptacoordinate structure. In 1, the two dinuclear vanadium(III) units bridged by the alkoxo group of hpnbpda are further linked by two diphenylphosphato and two oxo groups, resulting in a dimer-of-dimers. In 2, the two vanadium(III) units bridged by tphpn are further bridged by three phosphate ions with two different coordination modes. Complex 2 is oxidized in aerobic solution to yield complex 3, in which two of the three phosphate groups in 2 are substituted by oxo groups. 相似文献
53.
N. Goel S. J. Chung M. B. Santos K. Suzuki S. Miyashita Y. Hirayama 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):251
Measurements were made on a 0.2 μm four-terminal device, fabricated from an InSb/Al0.15In0.85Sb quantum well structure, at temperatures from 1.5 to 300 K. Negative bend resistance, a signature of ballistic transport, was observed at temperatures up to 205 K. The disappearance of the negative bend resistance at higher temperatures was accompanied by a non-linear dependence of the Hall voltage on magnetic field. The non-linearity indicates multiple-carrier conduction, which we characterize using quantitative mobility spectrum analysis. 相似文献
54.
系统研究了核磁共振碳谱及其化学位移规律性。并提出了一种新的分子图论参数:原子距离-边数矢量(μ矢量),并发现它与烷烃的13-CNMR有良好的相关性。 相似文献
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57.
Genki Funamoto Shigetoshi Tamura Kohichi Segawa Kam T. Wan Mark E. Davis 《Research on Chemical Intermediates》1998,24(4):449-459
Solid catalyzed isobutane alkylation has been investigated for decades, but it has not yet been applied in any commercial uses because of the rapid deactivation of the catalyst. Here, the alkylation reaction has been studied under supercritical conditions using metal-promoted and unpromoted sulfated zirconia as catalysts. The catalytic activity at the supercritical condition of 5.0 MPa, 423K was significantly higher than at lower reaction pressure conditions and the deactivation rate was clearly reduced, independent on the catalyst. Iron- and manganese-promoted sulfated zirconia (SFMZ) showed higher activities under all conditions than unpromoted sulfated zirconia (SZ). 相似文献
58.
J.Richard Blackborow Udo Feldhoff Friedrich-Wilhelm Grevels Robert H. Grubbs Akira Miyashita 《Journal of organometallic chemistry》1979,173(2):253-261
The catalytic cyclodimerization of norbornadiene by reaction with nickel atoms has been re-investigated. Nickela-cyclopentane derivatives are formed in the presence of α,α′-dipyridyl, α,α′-dipyridyl-exo-trans-endo-3-nickela-pentacyclo[9.2.1.15,8 02,10.04,9]-pentadeca-6,12-diene being the major component. By contrast, the catalytic dimerization leads predominantly to the exo-trans-exo isomer of pentacyclo[8.2.1.14,7.02,9.03,8] tetradeca-5,11-diene. A norbornadiene cyclotrimer of exo-trans-exo-trans-exo structure is subsequently formed. 相似文献
59.
[reaction: see text] A [5 + 2] cycloaddition reaction of a new five-carbon unit was developed on the basis of a dicobalt hexacarbonyl propargyl cation species. Under the influence of EtAlCl(2), [5-benzoyloxy-2-(triisopropylsiloxy)-1-penten-3-yne)]dicobalt hexacarbonyl reacted with enol triisopropylsilyl ethers to yield seven-membered dicobalt acetylene complexes in good yield. The reactions with cyclic enol silyl ethers as well as acyclic enol silyl ethers exhibited remarkably high diastereoselectivity. The cycloadducts can be easily converted into various kinds of cycloheptanone derivatives. 相似文献
60.
Racemic 2, 2'-bis(diphenylphosphino)-l, 1'-binaphthyl has been synthesized from 2, 2'-dihydroxy-l, l'-binaphthyl in two steps and resolved into optically pure (R)-(+) and (S) (-) enantiomers by the use of (+)-di-μ-chlorobis[(S)-N,N-dimethyl-α-phenylethylamine-2C,N]dipalladium. This new axially dissymmetric bis(triaryl)phosphine serves as an excellent ligand for Rh(l)-catalyzed asymmetric hydrogenations of α-(acylamino) acrylic acids or esters. Factors controlling the enantioselectivity and mechanistic aspects are discussed on the basis of the 31P-NMR measurements 相似文献