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971.
972.
973.
Xiao‐Ping Wang Panagiotis Angaridis Carlos A. Murillo F. Albert Cotton 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):m109-m111
The title compound, [Ru2(C2H3O2)4(C15H16N2O2)2], lies on a crystallographic inversion center and exhibits an Ru—Ru bond length of 2.2847 (8) Å. There are weak intramolecular hydrogen‐bonding interactions between the N1,N2‐di‐p‐anisylformamidine (HDAniF) ligands and the bridging acetate ligands. The molecule is one of the few examples of a crystallographically characterized axial bis‐adduct of a {Ru2}4+ complex with two N‐donor ligands. 相似文献
974.
Shan Gao Ji‐Wei Liu Li‐Hua Huo Hui Zhao Jing‐Gui Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):m25-m29
Two new two‐dimensional coordination polymers, poly[[[aqua(2,2′‐bipyridine‐κ2N,N′)manganese(II)]‐μ3‐p‐phenylenebis(oxyacetato)‐κ3O:O′:O′′] dihydrate], {[Mn(C10H8O6)(C10H8N2)(H2O)]·2H2O}n, (I), and poly[[di‐μ‐aqua‐bis[aquasodium(I)]]‐μ4‐p‐phenylenebis(oxyacetato)‐κO:O′,O′′:O′′′,O′′′′:O′′′′′], [Na2(C10H8O6)(H2O)4]n, (II), have been synthesized and characterized by X‐ray single‐crystal diffraction. In (I), there are two 1,4‐BDOA2− [p‐phenylenebis(oxyacetate) or, more commonly, benzene‐1,4‐dioxyacetate] ligands, each lying about inversion centres, while in (II), there is one such ligand and it also has crystallographically imposed inversion symmetry. In (I), each MnII atom displays an octahedral MnN2O4 configuration, defined by three carboxyl O atoms of different 1,4‐BDOA2− groups, two N atoms of one 2,2′‐bipyridine ligand and one water molecule. In (II), each NaI atom is octahedrally coordinated by one ether O atom, two carboxyl O atoms of different 1,4‐BDOA2− ligands and three water molecules. The metal ions in complexes (I) and (II) are bridged by 1,4‐BDOA2− groups into two‐dimensional layer structures. Furthermore, three‐dimensional supramolecular networks are constructed via hydrogen bonds in (I) and (II), and by additional π–π stacking interactions in (I). 相似文献
975.
Süheyla
zbey Arzu Akba Gülgün Ayhan‐Kilcigil Rahmiye Ertan 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o559-o561
In the molecule of the title compound, C26H21N3O5S, a new type of sulfonamide derivative with potential antibacterial activity, the flavone moiety is almost planar. The isoxazole and aminophenyl rings are also planar and make dihedral angles of 77.0 (2) and 81.4 (1)°, respectively, with the best plane of the flavone ring system. The crystal structure is stabilized by intra‐ and intermolecular hydrogen bonds. 相似文献
976.
Jie Chen Ning‐Hai Hu Jie Zhan Yue‐Sheng Li 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(7):m337-m338
A new polynuclear titanium(IV) complex, dichlorodeca‐μ2‐oxo‐hexakis(pentamethylcyclopentadienyl)hexatitanium(IV), [Ti6(C10H15)6Cl2O10], has been synthesized by hydrolysis of a titanium complex bearing an N‐(2‐hydroxy‐3,5‐dimethylbenzyl)diethanolamine Mannich ligand. The molecule has two O‐bridged Ti3O3 rings linked to two similar rings through a tetrahedrally O‐coordinated Ti atom. All Ti atoms except the central one are coordinated to pentamethylcyclopentadienyl (Cp*) ligands. The Cp* ligands are arranged with approximate symmetry with respect to the Ti/O/Cl core. 相似文献
977.
Yao Xinding Jinju Ma Ruina Fang Qishan Yuan Wei Liu 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2019,93(12):2340-2348
Russian Journal of Physical Chemistry A - The solubility of R-2[4-(6-chloro-2-benzoxazolyloxy)phenoxy]propanoic acid (abbreviated as Fenoxaprop-P) in acetone, methyl ethyl ketone (MEK),... 相似文献
978.
A series of novel [3]ferrocenophane-derived N/B frustrated Lewis pairs (FLPs) were synthesized and successfully applied to the catalytic hydrogenation of imines in 71–93% yields. This approach could be easily conducted on gram scale and provided versatile synthetic route for the key intermediate of sertraline hydrochloride without heavy metal residues. 相似文献
979.
An experimentally simple, efficient, and inexpensive catalyst system was developed for the N-arylation of imidazole, indole, pyrrole, alkyl alcohol amines, and alkyl amines with aryl iodides and bromides. The reaction proceeds in water-ethanol media at 120 °C for 12 h with Cu2O as the catalyst, 1-(2-methylhydrazine-1-carbonyl)-isoquinoline 2-oxide (L2) as the ligand, NaOH as the base to generate a wide range of N-arylated products in moderate to excellent yields. Aqueous medium, ease of operation, and broad substrate scope give the process a benign environmental profile. 相似文献
980.
The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on fB from two sum rules up to next-to-leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules II involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimension-four gluon condensate well. It is found that fB decreases with the increment of mB, and to compare with the Belle experimental data on fB, both sum rules I and II prefer smaller pole b-quarkmass, mb=4.68±0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172^{+23}_{-25} MeV for sum rules I and fB=214_{-34}^{+26} MeV for sum rules II. 相似文献