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211.
To develop a numerical solution of mentioned equations the method of factorized projection of integral operator kernel is applied. All matrix elements of the method are calculated analytically, being expressed in terms of two types of standard integrals: the overlap integrals and one-electron Coulomb integrals. To calculate the integrals we used the O(4)-symmetry of hydrogen-like atomic orbitals as well as operational technique of differentiation with respect to scalar and vector parameters. 相似文献
212.
A. G. Belous O. Z. Yanchevskii A. V. Kramarenko 《Russian Journal of Applied Chemistry》2006,79(3):345-350
Rounded nanosize particles of Co3O4 and NiO were prepared by precipitation with ammonium carbonate from cobalt and nickel nitrate solutions. Cobalt and nickel oxides and their precursors were characterized by thermal and X-ray phase analyses, electron microscopy, and IR spectroscopy. 相似文献
213.
A significant activation of the Ctbd1;N group in organonitriles upon their coordination to a platinum(IV) center has been found in the reaction of [PtCl(4)(RCN)(2)] (R = Me, Et, CH(2)Ph) with the nitrile oxides 2,4,6-R'(3)C(6)H(2)CNO (R' = Me, OMe) to give the (1,2,4-oxadiazole)platinum(IV) complexes (R = Me, R' = Me (1); R = Et, R' = Me (2); R = Et, R' = OMe (3); R = CH(2)Ph, R' = Me (4)); the [2 + 3] cycloaddition was performed under mild conditions (unless poor solubility of [PtCl(4)(RCN)(2)] precludes the reaction) starting even from complexed acetonitrile and propionitrile, which exhibit low reactivity in the free state. The reaction between complexes 2-4 and 1 equiv of Ph(3)P=CHCO(2)Me in CH(2)Cl(2) leads to the appropriate platinum(II) complexes (5-7); the reduction failed only in the case of 1 insofar as this complex is insoluble in the most common organic solvents. All the platinum compounds were characterized by elemental analyses, FAB mass spectrometry, and IR and (1)H, (13)C((1)H), and (195)Pt NMR spectroscopies, and three of them also by X-ray crystallography. The oxadiazoles formed in the course of the metal-mediated reaction were liberated almost quantitatively from their Pt(IV) complexes by reaction of the latter (complexes 2-4) with an excess of pyridine in chloroform, giving free 1,2,4-oxadiazoles and trans-[PtCl(4)(pyridine)(2)]; the sequence of the Pt(IV)-mediated [2 + 3] cycloaddition and the liberation opens up an alternative route for the preparation of this important class of heterocycles. 相似文献
214.
Electrolysis of aromatic aldehydes, malononitrile and malonate in methanol in an undivided cell in the presence of sodium bromide-sodium methoxide as double mediatory system results in the stereoselective formation of methyl (1R∗,5R∗,6R∗) 6-substituted 5-cyano-4,4-dialkoxy-2-oxo-3-azabicyclo[3.1.0]hexane-1-carboxylates in 50-70% yields. 相似文献
215.
Maxim A. Blagov Dr. Nataliya G. Spitsyna Dr. Vladimir A. Lazarenko Dr. Nikolai S. Ovanesyan Dr. Anatolii S. Lobach Dr. Leokadiya V. Zorina Dr. Sergey V. Simonov Dr. Vladimir B. Krapivin Dr. Alexei I. Dmitriev Dr. Mikhail V. Zhidkov Prof. Eduard B. Yagubskii 《欧洲无机化学杂志》2023,26(23):e202300239
As a result of the electrochemical oxidation process, the [FeIII(5Cl-thsa)2]− spin-crossover (SCO) anion with N2S2O2 coordination sphere transforms into N4O2-coordinated FeIII SCO neutral binuclear complex 2 with twist of two disulfide bridges. Each dimeric complex is a binuclear double-stranded helicate with similar chirality of both Fe centers. The crystal structure of the complex 2 ⋅ 3H2O at 100 K has a monoclinic C2/c space group and contains large cavities (about 21.5 % of the unit cell volume) half-filled by 3 water molecules per one dimer. The N4O2 coordination of iron(III) with two oxygen atoms (−O−) of phenoxy groups, two imine-type (−Nim=) nitrogen atoms of azomethine groups, one amidrazone-type (=NamidH) nitrogen atom and one ionized terminal group (−NionizH) of nitrogen has not been observed in CCDC so far. The oxidation state of the iron atoms in the dimeric complex was confirmed by 57Fe Mössbauer spectroscopy on 90 % enriched 57Fe sample. Mössbauer spectra and dc magnetic measurements demonstrated the partial HS-HS→LS-LS SCO in the 185–225 K temperature range. The details of the structure of complex 2 and the features of its magnetic properties were refined by theoretical analysis based on DFT calculations. The B3LYP* functional correctly predicting the energy of the spin-crossover process was revealed. 相似文献
216.
Pakhlov P Adachi I Aihara H Arinstein K Aushev T Aziz T Bakich AM Balagura V Barberio E Bedny I Belous K Bhardwaj V Bitenc U Bondar A Bozek A Bracko M Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Dalseno J Danilov M Dash M Drutskoy A Eidelman S Golob B Ha H Hayasaka K Hazumi M Heffernan D Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Ikado K Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Kah DH Kang JH Kapusta P Katayama N Kawai H Kawasaki T Kichimi H Kim YJ 《Physical review letters》2008,100(20):202001
We report a study of the processes e+e- -->J/psiD*D[over](*). In J/psiD*D[over]* we observe a significant enhancement in the D*D[over]* invariant mass spectrum, which we interpret as a new charmoniumlike state and denote X(4160). The X(4160) parameters are M=(4156(-20)+25+/-15) MeV/c2 and Gamma=(139(-61)+111+/-21) MeV. We also report a new measurement of the X(3940) mass and width: M=(3942(-6)+7+/-6) MeV/c2 and Gamma=(37(-15)+26+/-8) MeV. The analysis is based on a 693 fb(-1) data sample recorded near the Upsilon(4S) resonance by the Belle detector at the KEKB asymmetric-energy collider. 相似文献
217.
Natalia V. Lukasheva Satu Niemela Igor M. Neelov Anatolii A. Darinskii Franciska Sundholm Robert Cook 《Macromolecular Symposia》1999,146(1):251-257
Molecular mechanics studies of helix sense reversals and defects of the regularity in the helices of the same sense in the chains of poly(alkylisocyanates) were performed. The effect of medium was studied by using different values of the dielectric constant. Additionally to the reversals between the helix mirror images (MI) considered in the literature new types of reversals have been investigated. These reversals connect the helices having backbone torsion angles not only with opposite signs but also with inverse angle values (MII). For the MI reversals we report in addition to the small angle break conformations known from literature the discovery of new conformations of similar energy but with large angle breaks. Large angle reversals can be responsible for up to 50% of the chain persistence length in non-polar solvents. In vacuum MII reversals and defects have energies higher than MI reversals because of the strong electrostatic repulsion. At ϵ = 3.5 some defects have energy even lower that that of MI reversals. 相似文献
218.
A.?G.?Belous O.?I.?V’yunovEmail author S.?D.?Kobylianska A.?A.?Ishchenko A.?V.?Kulinich 《Russian Journal of General Chemistry》2018,88(1):114-119
The influence of the synthesis conditions (rotation speed used for spin-coating deposition of the film, film drying temperature, and the ratio of the PbI2 and CH3NH3I reactants in solutions) on the microstructure, phase composition, and spectral-luminescent properties of films of organic-inorganic perovskite CH3NH3PbI3–xCl x (x = 0, 0.02) was elucidated. 相似文献
219.
Peter P. Onys'ko Elena A. Suvalova Tatiana I. Chudakova Anatolii D. Sinitsa 《Heteroatom Chemistry》1993,4(4):361-364
The lithium diisopropylamide (LDA) induced regioselective 1,3-rearrangement of 3- and 2- pyridyl phosphates into the corresponding 3-hydroxy-4-pyridyl-and 2-hydroxy-3-pyridylphosphonates has been observed and investigated. The rearrangement is proposed as a useful method for a directed introduction of a phosphoryl group into a hydroxypyridine nucleus. 相似文献
220.
Stanislav Falkovich Anatolii Darinskii Nikolai Balabaev Igor Neelov 《Macromolecular Symposia》2009,278(1):105-113
Mechanical extension of the ubiquitin with constant speed in five different directions is simulated on coarse-grained Go-like and all-atom models. The anisotropy of the mechanical resistance of the protein is observed in agreement with experimental data. Differences and similarities between the results obtained for two models are discussed. It is shown that the unfolding begins from the rupture of contacts between residues located in the vicinity of points of the external load application. 相似文献