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101.
Kirillov AM Karabach YY Kirillova MV Haukka M Pombeiro AJ 《Dalton transactions (Cambridge, England : 2003)》2011,40(24):6378-6381
The new tricopper(II) complex [Cu(3)(μ(3)-BO)(H(3)L)(3)][BF(4)]·2H(2)O (1) with an unprecedented diamondoid-like [Cu(3)B(μ-O)(6)] core has been easily generated by self-assembly in an aqueous medium from Cu(NO(3))(2), NaBF(4), NaOH and Bis-Tris (H(5)L) biobuffer, (HOCH(2))(3)CN(CH(2)CH(2)OH)(2). Compound 1 efficiently promotes the mild single-pot hydrocarboxylation, by CO and H(2)O, of various linear and cyclic C(n) (n = 2-8) alkanes into the corresponding C(n+1) carboxylic acids. 相似文献
102.
An Ghysels Benjamin T. Miller Frank C. Pickard IV Bernard R. Brooks 《Journal of computational chemistry》2012,33(28):2250-2275
Dimension reduction is often necessary when attempting to reach longer length and time scales in molecular simulations. It is realized by constraining degrees of freedom or by coarse‐graining the system. When evaluating the accuracy of a dimensional reduction, there is a practical challenge: the models yield vectors with different lengths, making a comparison by calculating their dot product impossible. This article investigates mapping procedures for normal mode analysis. We first review a horizontal mapping procedure for the reduced Hessian techniques, which projects out degrees of freedom. We then design a vertical mapping procedure for the “implosion” of the all‐atom (AA) Hessian to a coarse‐grained scale that is based upon vibrational subsystem analysis. This latter method derives both effective force constants and an effective kinetic tensor. Next, a series of metrics is presented for comparison across different scales, where special attention is given to proper mass‐weighting. The dimension‐dependent metrics, which require prior mapping for proper evaluation, are frequencies, overlap of normal mode vectors, probability similarity, Hessian similarity, collectivity of modes, and thermal fluctuations. The dimension‐independent metrics are shape derivatives, elastic modulus, vibrational free energy differences, heat capacity, and projection on a predefined basis set. The power of these metrics to distinguish between reasonable and unreasonable models is tested on a toy alpha helix system and a globular protein; both are represented at several scales: the AA scale, a Gō‐like model, a canonical elastic network model, and a network model with intentionally unphysical force constants. Published 2012 Wiley Periodicals, Inc. 相似文献
103.
We prove that there are compact submanifolds of the 3-sphere whose interiors are not homeomorphic to any geometric limit of hyperbolic knot complements. 相似文献
104.
N. G. Bakhshiev S. K. Gularyan G. E. Dobretsov A. Yu. Kirillova V. Yu. Svetlichnyi 《Optics and Spectroscopy》2009,106(3):395-397
The solvatochromic regularities observed in solutions of 4-dimethylaminochalcone (DMCh) are investigated in terms of two independent theoretical approaches, i.e., semiempirical and quantum-chemical, and the results of these investigations are directly compared with each other for the first time. It has been shown that the values of the absolute solvation shift of the long-wavelength DMCh electronic absorption band determined by different methods are in a good quantitative agreement both with each other and with experimental data. This fact can be considered as a substantial additional justification of the conclusion on the predominantly nonspecific origin of intermolecular forces determining the mechanisms by which the DMCh fluorescent probe functions in biological systems. 相似文献
105.
I. D. Lobov M. M. Kirillova A. A. Makhnev L. N. Romashev A. V. Korolev M. A. Milyaev V. V. Proglyado N. S. Bannikova V. V. Ustinov 《Physics of the Solid State》2017,59(1):53-62
We investigated the field dependences of the magnetization and magnetoresistance of superlattices [Co(t x, Å)/Cu(9.6 Å)]30 prepared by magnetron sputtering, differing in the thickness of cobalt layers (0.3 Å ≤ t Co ≤ 15 Å). The optical and magnetooptical properties of these objects were studied by ellipsometry in the spectral region of hω= 0.09–6.2 eV and with the help of the transverse Kerr effect (hω= 0.5–6.2 eV). In the curves of an off-diagonal component of the tensor of the optical conductivity of superlattices with t Co = 3–15 Å, a structure of oscillatory type (“loop”) was detected in the ultraviolet region, resulting from the exchange splitting of the 3d band in the energy spectrum of the face-centered cubic structure of cobalt (fcc Co). Based on magnetic experiments and measurements of the transverse Kerr effect, we found the presence of a superparamagnetic phase in Co/Cu superlattices with a thickness of the cobalt layers of 3 and 2 Å. The transition from superlattices with solid ferromagnetic layers to superparamagnetic cluster-layered nanostructures and further to the structures based on Co and Cu (t Co = 0.3–1 Å) with a Kondo-like characteristics of the electrical resistivity at low temperatures is analyzed. 相似文献
106.
Wongi Jang Richard Taylor IV Pascal N. Eyimegwu Prof. Hongsik Byun Prof. Jun-Hyun Kim 《Chemphyschem》2019,20(1):70-77
Composite materials consisting of nanoscale gold particles and protective polymer shells were designed and tested as catalysts in various chemical reactions. Initially, the systematic incorporation of multiple gold nanoparticles into a poly(N-isopropylacrylamide) particle was achieved by an in situ method under light irradiation. The degree of gold nanoparticle loading, along with the structural and morphological properties, was examined as a function of the amount of initial gold ions and reducing agent. As these gold nanoparticles were physically-embedded within the polymer particle in the absence of strong interfacial interactions between the gold nanoparticles and polymer matrix, the readily-accessible surface of the gold nanoparticles with a highly increased stability allowed for their use as recyclable catalysts in oxidation, reduction, and coupling reactions. Overall, the ability to integrate catalytically-active metal nanoparticles within polymer particles in situ allows for designing novel composite materials for multi-purpose catalytic systems. 相似文献
107.
M. V. Korolevich S. G. Kirillova V. N. Piottukh-Peletsky V. M. Andrianov 《Journal of Applied Spectroscopy》2008,75(5):613-620
A detailed interpretation of the IR spectrum of methyl-3,4-anhydro-α-D-talohexopyranoside that is based on complete calculation
of normal vibration frequencies and absolute IR absorption band intensities of the molecule and a comparison of the results
obtained with the corresponding experimental data is given for the first time. The influence of the epoxy group on the absorption
bands characteristic of the pyranose ring has been analyzed.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 597–605, September–October, 2008. 相似文献
108.
Kai-Jie Chen John J. Perry IV Hayley S. Scott Qing-Yuan Yang Michael J. Zaworotko 《Chemical science》2015,6(8):4784-4789
Two isostructural metal–organic materials, Tripp-1-M (Tripp = 2,4,6-tris(4-pyridyl)pyridine; M = Co, Ni), that exhibit binodal 3,6-connected pyr network topology have been prepared and characterized. Tripp-1-M are based upon a novel M7F12
2+ cluster that possesses 12 connection points but, because of double cross-linking by 3-connected Tripp ligands, it functions as a 6-connected supermolecular building block (SBB). 相似文献
109.
T. Ya. Medved' N. P. Nesterova P. V. Petrovskii T. D. Kirillova M. I. Kabachnik 《Russian Chemical Bulletin》1978,27(8):1497-1504
Conclusions A number of complexes of tetraaryl (alkyl) alkylenediphosphine dioxides with uranyl nitrate have been synthesized. Coordination of both P=O groups with the uranyl ion is observed in the complexes of methylenediphosphine and cis-tetraarylvinylenediphosphine dioxides; in complexes of trans-tetraaryl (alkyl) vinylenediphosphines, only one P=O group is involved in complexing. Tetraphenylethylenediphosphine dioxide forms both types of complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1714–1721, August, 1978.We thank A. M. Rozen for discussing the results. 相似文献
110.