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991.
YAO Tian-Ming YOU Xiao-ZengCoordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing ChinaYANG Qing-ChuanChemistry Department Beijing University Beijing China 《中国化学》1994,12(3):248-257
The reaction of CuCl2-2H2O or NiCl2.6H2O with K2(C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2]- or [Ni(C5H6S4)2]- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2]0 = [M(C5H6S4)2]1-= [M(C5H6S4)2]2-. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2] belongs to monoclinic space group P21/c with a=17.576(5), 6=10.883(2), c=17.773(4) A,B=91.07(2)0, Z=4, and o(calcd.)=1.348 g/cm3. Final result is R=0.059 for 2959 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.134(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.429 A. The solid powder ESR s 相似文献
992.
993.
Li2H4I2O10, the First Tetrahydrogendimesoperiodate Li2H4I2O10 has been obtained as an intermediate during the dehydration of LiH4IO6 · H2O to LiIO4, for the first time. According to the results of an X-ray structure determination (monoclinic, P21/n, a = 533.98(4), b = 471.85(4), c = 1431.48(10) pm, β = 91.614(7)°, Z = 2, 726 diffractometer data, R = 0.056), Li2H4I2O10 contains the previously unknown tetrahydrogendimesoperiodate ion H4I2O102?, consisting of two edge-shared IO6 octahedra. They are connected with LiO6 octahedra via common edges and vertices. The crystals are non-merohedrally twinned along (100). 相似文献
994.
MARIA BOCHENSKA VICTOR CH. KRAVTSOV VALERII E. ZAVODNIK 《Journal of inclusion phenomena and macrocyclic chemistry》1997,28(2):125-140
The structure of the lithium complex with1,3,5-tris[oxymethylene(N,N-dicyclohexyl)carboxyamido]cyclohexanehas been determined by the X-ray method.The compound is triclinic, space group P¯1,a = 15.623(3), b = 19.279(4),c = 19.295(4)Å = 102.32(3), = 92.45(3), = 105.67(3)0, V = 5436(2)Å3, Z = 4. Itscomposition is represented by the formulaC48H82N3O6LiI 0.5H2O. The lithium cationis encapsulated in a polar pseudo-cavity of six oxygen atoms of the ligandmolecule and displays a distorted trigonal prism coordination. The conformationof the ligand in the solid state complex has been compared with the conformationof the complex in solution determined by 1H-NMR measurements.Supplementary data relevant to this publication have been deposited with the British Library, No. SUP 82224 (21 pages). 相似文献
995.
996.
997.
Synthesis, Crystal Structure, and Spectroscopic Characterization of Tetraphosphorus Hexaoxide Monoselenide, P4O6Se P4O6Se has been synthesized by photochemical reaction between P4O6 and elemental selenium in CS2 in presence of iodine as a catalyst. Single crystals form at purification via sublimation. The compound (m. p. 46°C) crystallizes in the monoclinic space group P21/c (no. 14) with a = 1 051.8(2), b = 652.9(1), c = 1 178.6(2) pm, β = 109.29(1)°, Z = 4. Within the limits of experimental error, the molecules exhibit C3v symmetry. IR, Raman, and 31P n.m.r. (solution) spectra of the compound are reported and discussed. The geometry of the Molecule as determined by theoretical methods (SCF level) is in good agreement with the experimental results. 相似文献
998.
ZHANG Xiu-Tang ZHAN Xiao-ping WU Ding-Ming ZHANG Quan-Zheng CHEN Shu-mei YU Ya-qin LU Can-Zhong 《结构化学》2002,21(6)
The new oxovanadium (Ⅴ) complex, [PyH][VO2(L)] 1 (salicyladehyde 5-bromo salicyloylhydrazone is abbreviated as H2L; Hpy is protonated pyridine) was obtained from a refluxed solution of VOSO4 and H2L in acetonitrile-methanol-pyridine. Similarly, another new complex, [VO(L)(OCH3)] 2 was synthesized by refluxing VOSO4 and H2L in methanol-pyridine. Crystal data for 1: C19H15N3O5BrV, Mr = 496.2, monoclinic, P21/n, a = 7.1885(3), b = 9.2718(3), c = 28.803(1) (A), ( = 96.185(1)(, Z = 4 and V = 1908.6(1) (A)3; for 2: C15H12N2O5BrV, Mr = 431.1, monoclinic, P21/n, a = 12.202(2), b = 8.045(2), c = 16.604(3)(A), ( = 101.29(3)(, Z = 4 and V = 1598.4(2)(A)3. The structures of 1 and 2 have been determined by X-ray analyses and reveal that the coordination environments of V atoms in both complexes are of square-based pyramid. Three of the four based donor atoms are from the tridentate "ONO" donor ligand while the fourth is one terminal oxygen atom with the V(1)–O(3) distance 1.646(4) (A) for 1 and one -OCH3 group with the V(1)-O(3) distance 1.753(3)(A) for 2. The V(1)-O(4) terminals occupy the axial sites in both cases. The complexes are also characterized by IR and 1H NMR spectroscopies. 相似文献
999.
L. C. Du S. C. Tiong Q. Zhu Allan S. Hay 《Journal of polymer science. Part A, Polymer chemistry》2002,40(21):3579-3591
Zinc glutarates were synthesized from zinc oxides with varying purities via different stirring routes. The particle size and structure of these zinc glutarates were determined by wide‐angle X‐ray diffraction, transmission electron microscopy, and the laser particle size analyzer technique. The results demonstrated that the crystallinity and crystalline perfectness of zinc glutarate are the crucial factors that affect the catalytic activity for the copolymerization of carbon dioxide (CO2) and propylene oxide (PO). Additionally, the catalyst with a small particle size dramatically increased the yield of the copolymerization between CO2 and PO. High‐molecular‐weight and regular molecular structure poly(propylene carbonate)s (PPC)s were obtained from CO2 and PO with the synthesized zinc glutarates. Very high catalytic activity of 160.4 g polymer/g catalyst was afforded. The NMR technique revealed that the PPC copolymer exhibits an exact alternating copolymer structure. The relationships between the crystallinity and the particle size of catalyst with the catalytic activity are correlated and discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3579–3591, 2002 相似文献
1000.
Adachi K Sugiyama Y Yoneda K Yamada K Nozaki K Fuyuhiro A Kawata S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(22):6616-6628
Novel triply hydrogen bonded suprastructures based on [M(tdpd)2(L)2]2- (H2tdpd=1,4,5,6-tetrahydro-5,6-dioxo-2,3-pyrazinedicarbonitrile, L=solvent) and melamine-analogous cations have been synthesized and characterized. The use of anions containing two AAA sets from [M(tdpd)2(L)2]2- together with cations containing one DDD set (A=hydrogen-bond acceptor, D=hydrogen-bond donor) leads to the formation of complementary triply hydrogen bonded modules in the solid state. In all cases, the building module is further extended via additional hydrogen-bonding interactions to produce a tape, and tapes are assembled into sheets. These results show that a hydrogen-bonded module consisting of different kinds of building blocks, one of which is a metal complex that includes hydrogen-bond acceptor sites and the other is a hydrogen-bond donor molecule, will be attractive for constructing metal-containing supramolecular systems by the self-assembly technique. 相似文献