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211.
Ultrasonic speeds u in {(1?x)C6H6 + xC6H5NO2} were measured by a fixed-path pulse technique at 293.15, 303.15, and 313.15 K under pressures up to 30 or 200 MPa with an observed error of less than 0.3 per cent. Curves of u(x) change smoothly in the benzene-rich region. But near x = 0.7, u(x) apparently deviates from a smooth curve, and the apparent gap becomes progressively greater as the temperature is reduced or the pressure is raised. From the experimental values, densities, isentropic compressibilities, and expansivities were calculated at high pressures. These quantities also show unusual behavior with x similar to that of u. 相似文献
212.
Yasushi Nishihara Masanori Okamoto Yoshiaki Inoue Mikihiro Miyazaki Mitsuru Miyasaka Kentaro Takagi 《Tetrahedron letters》2005,46(50):8661-8664
Alkynylboronates are employed as a practical and versatile precursor for a variety of π-conjugated organic compounds. In the presence of a Cu(I) or Cu(II) salt, transformation of alkynylboronates into the corresponding 1,3-diynes upon exposure to air takes place readily in aprotic polar solvents such as DMI. 相似文献
213.
Single crystals of the strontium copper tellurium oxochloride SrCu2(TeO3)2Cl2 were synthesized via solid-gas reactions in sealed evacuated silica tubes. The compound crystallizes in the monoclinic system, space group P21, a=7.215(2), b=7.2759(15), c=8.239(2) Å, β=96.56(4)°, Z=2. The building units are [SrO6Cl2] irregular polyhedra, [CuO4] and [CuO3Cl] square planes, [TeO3E] tetrahedra and [TeO3+1E] trigonal bipyramids; E being the 5s2 lone pair of Te(IV). The Cu atoms can be regarded as forming a chain of weakly connected dimers. The magnetic susceptibility of the compound shows a broad maximum typical for antiferromagnetic spin fluctuations with a non-magnetic ground state. A Heisenberg spin model with coupled s=1/2 dimers leads to a satisfactory fitting of the experimental data. 相似文献
214.
Takagi A Yanagawa Y Tsuda A Aratani N Matsumoto T Osuka A Kawai T 《Chemical communications (Cambridge, England)》2003,(24):2986-2987
Geometrical structures of chain porphyrin arrays adsorbed on Cu(100) are observed by STM: a bridge-like bent structure for meso-meso singly linked orthogonal hexamer, whereas a rigid planar and one-dimensionally stacked structure for meso-meso, beta-beta, beta-beta triply-linked hexamer. 相似文献
215.
T. Takagi 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,3(2):271-278
The ionized cluster beam (ICB) technique can be classified as an ion-assisted technique for film formation, and it has the feature of transferring low energy and equivalently high current beams. The clusters can be created by condensation of supersaturated vapour atoms produced by an adiabatic expansion process. These clusters are large size macro-aggregates of 100–2,000 atoms formed by pure expansion of vapourized solid state materials. The clusters are first partially ionized by an electron impact, then the kinetic energy can be added to the ionized clusters. The ICB has unique capabilities of film deposition due to cluster properties and its low energy ion beam transport in a range from thermal energy to a few hundred eV, with the ability to use the effective influence from the ions without space charge problems. This allows high quality deposition and epitaxy of materials at low temperature onto a wide variety of substrates and even permits the formation of thin film materials not previously possible. 相似文献
216.
Arylzinc compounds, ArZnX, were conveniently prepared in high yields by the reaction of zinc powder with aryl iodides, which contain electron-withdrawing groups such as CO(2)CH(3), CN, Br, or CF(3) at the ortho-, meta- or para-position, or electron-donating groups such as CH(3), OCH(3), or H, at 70 degrees C in THF, at 100 degrees C, or at 130 degrees C in diglyme, respectively. Pd(dba)(2) exhibited an outstanding efficient catalytic effect for the cross-coupling of these ethereal solutions of ArZnX with allylic halides to afford a variety of functionalized allylbenzenes in high yields; the reactions were mostly carried out at 0 degrees C for 5-30 min in the presence of 5 mol % of catalyst. The conversion of the aryl iodides to allylbenzenes via two reactions could be accomplished in one pot. 相似文献
217.
Takayoshi Suzuki Atsushi Hasegawa Hiroshi Yamaguchi Kazuo Kashiwabara Hideo D. Takagi 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):m461-m463
In the title compound, cis‐[Pd(C5H14NP)2]Cl2·CH4O, the coordination geometry around the PdII center is distorted square planar, with a cis‐P2N2 configuration of the two chelating (3‐aminopropyl)dimethylphosphine (pdmp) ligands. The six‐membered pdmp chelate rings adopt chair conformations, and pairing of the chairs designates the complex cation as a (Cs)‐chair2 conformer. The distances between the PdII center and the Cl− anions are greater than 4.5 Å, indicating no obvious interaction. 相似文献
218.
219.
Chuzo Iwata Yoshiji Takemoto Hitoshi Kubota Takeshi Kuroda Takeshi Imanishi 《Tetrahedron letters》1985,26(27):3231-3234
(±)-Oxylubimin (1), the highest oxidized spirovetivane-type phytoalexin, was totally synthesized with high stereoselectivity using a novel method for α′-hydroxylation of α,β-unsaturated ketones. 相似文献
220.
E. coli cells were inactivated with visible light in the presence of toluidine blue as a photo-sensitizer. This photodynamic effect was partially protected with α-tocopherol. Not only pH but the concentration of the buffer during irradiation also affected the survival. The addition of osmotic stabilizers such as KCI, glycerol and polyethyleneglycol to the buffer increased the survival. The difference in singlet oxygen production in these reaction mixtures could not be related to these features. Furthermore, the survival was also dependent upon both irradiation temperature and cultivation temperature of the cells. These results with E. coli cells support the notion that one of the primary targets of toluidine blue sensitized photodynamic inactivation is cytoplasmic membrane, although other factors than cytoplasmic membrane also influence the survival of the cells. 相似文献