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991.
A series of salts, with the 9-aminoacridinium cation (9-AA) and aromatic carboxylic acid: benzoate (1), ortho-phthalate (2), and salicylate (3) anions have been synthesized and characterized using X-ray diffraction. In the crystal packing, the ions are linked via N-H?O, O-H?O, and C-H?O hydrogen bonds. Analysis of the hydrogen bonds in the crystal lattices of the title compounds shows that the cations and anions form tetramers. The ions in these tetramers are linked via N(amino)-H?O(carboxy) hydrogen bonds forming R22(8) (1 and 3) or R24(15) (2) hydrogen bond ring motifs. The cations interact through π-π interactions in the ABBA (1), AB (2) or ABA (3) arrangement to form columns (1 and 2) or chains (3). 相似文献
992.
The synthesis of Ni(dtc)2 [dtc = diethyldithiocarbamate] has been achieved by the interaction of NiL(ClO4)2 with sodium diethyldithiocarbamate. Although single crystal structure of this complex was already reported (R = 10.6%), we were able to refine crystal structure up to R = 2.99%. We also observed rare C-H?Ni anagostic interactions generally exhibited by d8 complexes which were overlooked previously. To investigate the structure of Ni(dtc)2 in solution, variable temperature NMR spectra in solution have also been recorded between 25 and −50 °C. Ni(dtc)2 was also tested for antibacterial and antifungal activities. It showed higher activity against the bacteria and fungi than the known antibiotics. 相似文献
993.
Six new compounds: [M(dps)(dca)2]∞ (1, M = Cd; 2, M = Fe), [Cu(dps)(dca)2(CH3OH)2]∞ (3), [M(dps)2(SCN)2(H2O)2]∞ (4, M = Cd; 5, M = Fe), [Cu(dps)4(SCN)2]∞ (6), (dps = 4,4′-dipyridyl sulfide, dca = dicyanamide) were synthesized, characterized by FT-IR, element analysis and TG. Their structures were determined by single crystal X-ray diffraction. According to the structure analysis, compounds 1 and 2 are three-dimensional microporous frameworks constructed by Cu-dps-Cu and Cu-dca-Cu bridges; compound 3 shows a zigzag chain constructed by a Cu-dps-Cu bridge; compounds 4 and 5 show double-stranded chains constructed by a Cu-(dps)2-Cu bridge while thiocyanate anions act as terminal groups; compound 6 is a mononuclear compound. Moreover, compound 1 shows visible yellow luminescence under UV light irradiation and such phenomenon is mainly attributed to inter-ligand transitions. 相似文献
994.
995.
Anastasia N. GeorgopoulouConstantinos G. Efthymiou Constantina PapatriantafyllopoulouVassilis Psycharis Catherine P. RaptopoulouManolis Manos Anastasios J. TasiopoulosAlbert Escuer Spyros P. Perlepes 《Polyhedron》2011,30(18):2978-2986
The synthetic investigation of the NiII/M(NO3)3·6H2O/di-2-pyridyl ketone [(py)2CO] tertiary reaction system in EtOH has yielded triangular Ni2M cationic complexes (M = lanthanide, Y). The reaction between Ln(NO3)3·6H2O, Ni(ClO4)2·6H2O, (py)2CO and base (1:3:3:3) in EtOH under gentle heating gave the isostructural complexes [Ni2Ln{(py)2C(OEt)(O)}3{(py)2C(OH)(O)}(NO3)(H2O)](ClO4)2 (Ln = Gd, 2; Ln = Tb, 3) in high yields. The ligands (py)2C(OEt)(O)− and (py)2C(OH)(O)− are the monoanions of the hemiketal and gem-diol derivatives of (py)2CO, respectively, formed in situ in the presence of the metal ions. The cations of 2 and 3 consist of one 8-coordinate LnIII and two distorted octahedral NiII atoms in an essentially isosceles, triangular arrangement capped by a central μ3-Ο− atom of the unique 3.3011 (Harris notation) (py)2C(OH)(O)− ligand. Each metal-metal edge is bridged by the deprotonated O atom of one 2.2011 (py)2C(OEt)(O)− ligand. The isostructural complexes [Ni2M{(py)2C(OEt)(O)}4(NO3)(H2O)]2[M(NO3)5](ClO4)2 (M = Y, 4 ; M = Tb, 5 ; M = Dy, 6) were prepared by the 1:1 reaction of the mononuclear “metalloligand” [Ni(O2CMe){(py)2CO}{(py)2C(OH)2}](ClO4) (1) and M(NO3)3·6H2O in EtOH under mild heating in moderate to good yields. The structures of the dications of 4-6 are similar to those in 2 and 3, the only difference being the replacement of the unique 3.3011 (py)2C(OH)(O)− ligand of the latter by one 3.3011 (py)2C(OEt)(O)− group in the former. The YIII, TbIII and DyIII atoms in [M(NO3)5]2− are coordinated by five bidentate chelating nitrato groups. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the ligands. Variable temperature, solid-state direct current magnetic susceptibility and magnetization studies were carried out on dried samples of 2-4. The data indicate ferromagnetic Ni?Ni and Ni?Gd exchange interactions, and an ST = 11/2 ground state for 2. Complex 3 is characterized by a high-spin ground state while the ferromagnetic Ni?Ni interaction for 2 is independently supported by the study of 4. No out-of-phase, alternating current susceptibility signals have been detected for 3 that would be indicative of SMM behavior. 相似文献
996.
997.
998.
Zhao-Di LiuXuan-Jun Zhang Jie-Ying WuFu-Ying Hao Hong-Ping ZhouYu-Peng Tian 《Polyhedron》2011,30(2):279-283
Five metal-bridged biferrocene complexes of the Schiff-base ligand (HL = S-benzyl-N-(ferrocenyl-1-methyl-methylidene)dithiocarbazate) have been studied by single crystal X-ray diffraction and 57Fe Mössbauer spectroscopy. The crystal structures of the complexes show that the central metal ions are tetra-coordinated by two ligands in two modes: the central d8 transition metal ions (Ni2+, Pd2+, and Pt2+) are nearly square-planar coordinated and the d10 transition metal ions (Zn2+ and Cd2+) are tetrahedrally coordinated. Interestingly, the isomer shifts in 57Fe Mössbauer spectroscopy are also of two kinds: d8 transition metal ions (0.097-0.247 mm/s) and d10 transition metal ions (0.416-0.435 mm/s). 相似文献
999.
Dipravath Kumar SethSamaresh Bhattacharya 《Polyhedron》2011,30(15):2438-2443
The reactions of N-(aryl)pyridine-2-aldimines (L-R; R = OCH3, CH3, H, Cl and NO2), derived from pyridine-2-aldehyde and para-substituted anilines, with CuI in methanol under ambient conditions afford a series of brown complexes of the type [{Cu(L-R)I}2]. The structure of the [{Cu(L-OCH3)I}2] complex has been determined by X-ray crystallography. In these dimeric complexes the two copper centers are linked through an iodo-bridge, and the L-R ligands are coordinated to the metal center through the pyridine-nitrogen and imine-nitrogen. All the complexes show characteristic 1H NMR signals and intense MLCT transitions in the visible region. These complexes also show an emission near 465 nm, whilst they are excited at 340 nm, with relatively poor quantum yields (φ ∼0.002 at 298 K). Cyclic voltammetry on all the complexes shows two successive Cu(I)-Cu(II) oxidations on the positive side of SCE, and a reduction of the coordinated imine ligand on the negative side. These copper(I) complexes are found to efficiently catalyze Suzuki type C-C coupling reactions. 相似文献
1000.
Gabrieli L. ParrilhaAuthor VitaeRafael P. VieiraAuthor Vitae Anayive P. RebolledoAuthor VitaeIsolda C. MendesAuthor Vitae Lidia M. LimaAuthor VitaeEliezer J. BarreiroAuthor Vitae Oscar E. PiroAuthor VitaeEduardo E. CastellanoAuthor Vitae Heloisa BeraldoAuthor Vitae 《Polyhedron》2011,30(11):1891-1898
Complexes [Zn2(HL1)2(CH3COO)2] (1) and [Zn2(L2)2] (2) were synthesized with salicylaldehyde semicarbazone (H2L1) and salicylaldehyde-4-chlorobenzoyl hydrazone (H2LASSBio-1064, H2L2), respectively. The crystal structure of (1) was determined. Upon recrystallization of previously prepared [Zn2(HL2)2(Cl)2] (3) in 1:9 DMSO:acetone crystals of [Zn2(L2)2(H2O)2]·[Zn2(L2)2(DMSO)4] (3a) were obtained. The crystal structure of 3a was also determined. All crystal structures revealed the presence of phenoxo-bridged binuclear zinc(II) complexes. 相似文献