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981.
Keiichi Satoh Toshio Suzuki Kiyoshi Sawada 《Monatshefte für Chemie / Chemical Monthly》2001,132(10):1145-1155
Summary. The molecular structures of bis-(pyridine base) complexes of cadmium(II) chloride and bromide, where the pyridine base is pyridine ( py), 3-methylpyridine (3-Me-py), 4-methylpyridine (4-Me-py), and 4-ethylpyridine (4-Et-py), were investigated by means of single-crystal X-ray diffraction and Raman spectroscopy. The crystal structures of CdCl2 py
2 (1), CdCl2(3-Me-py)2 (2), and CdCl2(4-Me-py)2 (3) were determined. All crystals are monoclinic; 1: a = 17.784(2), b = 8.666(1), c = 3.8252(7) ?, β = 91.54(1)°, space group: P21/n; 2: a = 11.89(1), b = 14.41(1), c = 3.874(6) ?, β = 92.3(1)°, space group: P21/a; 3: a = 21.091(2), b = 3.8884(5), c = 18.2317(3) ?, β = 113.64(1)°, space group: C2/c. The structures were refined to R/R
w
values (%) of 3.2/5.5, 3.0/5.0, and 3.4/5.1 for 1–3. All cadmium atoms are octahedrally coordinated with the chloride ions forming infinite di-μ-chloro polymeric linear chains
and the nitrogen atoms of the pyridine base in trans configuration. The Cd chains are oriented along the c-axis in 1 and 2 and along the b-axis in 3. The crystal structures indicate the absence of a peculiar interaction between the polymeric chains. The Raman spectra of eight complexes were measured in the range of 550–50 cm−1, and the Raman peaks originating from cadmium-halogen vibrations were assigned. The Raman spectra of 1 and 2 are quite alike in the lattice mode vibration region. The resemblance of the cadmium-halogen vibration peaks indicates the
same halogenide ion bridged octahedral structure for all complexes.
Received March 27, 2001. Accepted (revised) June 19, 2001 相似文献
982.
Kiyoshi Sawada Eiji Takahashi Tomokazu Horie Keiichi Satoh 《Monatshefte für Chemie / Chemical Monthly》2001,36(4):1439-1450
The distribution of tetraalkylammonium ions (C n H 2n+1 )4N+ (R +, TAAn +, n = 4–7) with picrate ion (pic −) and inorganic anions X −, (Cl−, Br−, ClO− 4), into various inert organic solvents was studied at 25.0°C. The distribution data were analyzed by taking into consideration the distribution of ion pairs, R + · X −, and the dimerization of the ion pairs, (R + · X −)2, in the organic phase. The ion-pair, distribution constant, K dist, increases with increasing chain length of the tetraalkylammonium ion and with increasing ionic radius of the anion. The values of K dist show a good correlation with the E T value of solvent, i.e. the solvation ability with respect to the anion, and smoothly increase with increasing E T. The effect of the solvent on the dimerization constants, K dim, is markedly different between the ion pairs of picrate ion and inorganic anions. In the case of picrate, K dim significantly decreases with decreasing length of the alkyl chain of the tetraalkylammonium ion, but hardly changes by changing the solvent. On the other hand, in the case of ion pairs of inorganic anions the value of K dim decreases with decreasing E T and is almost constant for all anions. These results were reasonably explained by the difference of the solvation of the anion moieties of the monomeric and dimeric ion pairs. 相似文献
983.
Taku Matsui 《Communications in Mathematical Physics》2001,218(2):393-416
We consider the relationship between the symmetry breaking and the split property of pure states of quantum spin chains.
We obtain a representation theoretic condition implying that the half-sided uniform mixing condition leads to symmetry breaking
of translationally invariant pure states. This is a mathematical generalization of Dichotomy previously found by I. Affleck and E. Lieb and M. Aizenman and B. Nachtergaele for ground states of a special class of Hamiltonians.
Received: 1 February 1999 / Accepted: 5 December 2000 相似文献
984.
985.
Osamu Kikuchi Toshio Watanabe Yusuke Satoh Yuichi Inadomi 《Journal of Molecular Structure》2000,507(1-3):53-62
Ab initio MO GB theory which includes the continuum model of solvent effect using generalized Born formula has been applied to the dimerization reaction of HCN in aqueous solution which is the starting step in prebiotic synthesis of purine precursors from aqueous hydrogen cyanide. Three steps considered were: (i) the reaction of HCN and H2O to produce the CN− anion, (ii) the reaction of CN− with HCN to give the NC–CH=N− anion, and (iii) the addition of a proton to the anion to give iminoacetonitrile. The formation of CN− ion from HCN in aqueous solution requires 15.1 kcal/mol (the experimental value estimated from the dissociation constant of HCN in water is 14.8 kcal/mol). The reaction of CN− with HCN requires the activation energy of 32.2 kcal/mol (MP2/6-31++G**//HF/6-31++G**) to give the dimer. This barrier height is reduced to 26.1 kcal/mol when HCN is associated with H3O+. In the presence of NH3 in aqueous solution, CN− is produced easily by the reaction of HCN and NH3 with a low activation energy of 4.3 kcal/mol. It was shown that the formation of CN− becomes easier in ammoniacal solution, and the dimerization occurs efficiently in aqueous solutions which contain NH3. 相似文献
986.
H. Tamura K. Tanida D. Abe H. Akikawa K. Araki H. Bhang T. Endo Y. Fujii T. Fukuda O. Hashimoto K. Imai H. Hotchi Y. Kakiguchi J. H. Kim Y. D. Kim T. Miyoshi T. Murakami T. Nagae J. Nishida H. Noumi H. Outa K. Ozawa T. Saito J. Sasao Y. Sato S. Satoh R. Sawafta M. Sekimoto T. Takahashi L. Tang H. H. Xia S. H. Zhou L. H. Zhu 《Nuclear Physics A》2000,670(1-4):249-256
We report on the first observation of hypernuclear γ transitions using germanium detectors. Using a large-acceptance Ge detector system, we observed two γ transitions in Λ7Li, the spin-flip
transition at 689±4keV and the
transition at 2050±2 keV (preliminary). The strength of the ΛN spin-spin interaction is derived from the energy of the former transition. As for the latter transition, B(E2) was measured to be 3.9±0.6±0.4 e2fm4 (preliminary), which indicates a shrinkage of the nuclear size of Λ7Li from 6Li and confirms “glue-like role” of Λ. 相似文献
987.
Shin Satoh 《Proceedings of the American Mathematical Society》2000,128(9):2789-2793
We show that if a non-orientable surface embedded in 4-space has a projection into 3-space with at most one triple point, then it is ambient isotopic to a connected sum of some unknotted projective planes and an embedded surface in 4-space with vanishing normal Euler number.
988.
Ken Sakai Mai Kurashima Norinobu Akiyama Naoki Satoh Takashi Kajiwara Tasuku Ito 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(9):m345-m349
In the title compound, [Pt2(C5H10NO)2(C12H8N2)2](NO3)2·2H2O, the intradimer Pt—Pt distance is relatively short [2.8489 (17) Å], which must be due to the strong intramolecular π–π‐stacking interactions between the phenanthroline moieties. The dimers stack along the c axis, forming one‐dimensional columns in which very intriguing d–d, π–π and d–π interactions exist. Although the dimer–dimer Pt...Pt distances are very long [4.340 (2) and 4.231 (2) Å], some short interdimer Pt...C contacts leading to strong interdimer associations are found [3.325 (19) and 3.402 (19) Å]. 相似文献
989.
Harumi Kaga Atsushi Narumi Toshifumi Satoh Takeshi Matsuda Mohd. Sharfuddin Toyoji Kakuchi 《Macromolecular Symposia》2002,181(1):95-100
Coupling reactions of TEMPO-terminated polystyrene (PS-TEMPO) with divinylbenzene were performed in the presence of vinyl saccharides 1 , successfully producing star-shaped polystyrenes with glycoconjugated core 2 . Amphiphilic star-shaped polystyrenes with cores containing saccharide as hydrophilic segments 3 were obtained by the deacetylation of 2 , which exhibited an encapsulation ability toward methyl orange (MO) in chloroform. A positive Cotton effect was observed in the CD spectrum for the MO/ 3 in the adsorption area of MO, indicating that MO existed in a chiral segment, i.e., the glycoconjugated core. 相似文献
990.
Kotaro Satoh Masami Kamigaito Mitsuo Sawamoto 《Journal of polymer science. Part A, Polymer chemistry》2000,38(15):2728-2733
Aqueous sulfonic acids (HOSO2R; R = CH3, Ph‐p‐CH3, and Ph‐p‐NO2), coupled with a water‐tolerant Lewis acid, ytterbium triflate [Yb(OTf)3; OTf = OSO2CF3], initiate the cationic suspension polymerization of p‐methoxystyrene (pMOS) in heterogeneous aqueous media. They induce controlled polymerization of pMOS at 30 °C, and the molecular weights of the polymers (weight‐average molecular weight/number‐average molecular weight ∼ 1.7) increase with conversion. These suspension polymerizations are initiated by the entry of sulfonic acid from the aqueous phase into the organic phase and proceed via reversible activation of the sulfonyl terminus by the Lewis acid. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2728–2733, 2000 相似文献