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981.
《Journal of Coordination Chemistry》2012,65(5):383-388
A new manganese(II) complex [Mn(im2-py)(tp)(H2O)2]·1.25H2O (im2-py=2-(2'-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl and tp=terephthalato dianion) has been synthesized and characterized structurally and magnetically. The crystal structure consists of neutral chains of manganese(II) ions linked by the terephthalate ligand. Variable temperature magnetic susceptibility data exhibit a weak antiferromagnetic coupling between the manganese(II) ion and the imino nitroxide radical. 相似文献
982.
《Journal of Coordination Chemistry》2012,65(2):316-324
2-(2,2′?:?6′,2″-Terpyridin-4′-yl)phenol has been prepared with an improved one-pot method. The reaction between the ligand and MnCl2 in ethanol at ambient or hydrothermal conditions afforded dichlorido[2-(2,2′?:?6′,2″-terpyridin-4′-yl)phenol-κ3 N,N′,N″]manganese(II) and dichloridobis[µ-2-(2,2′?:?6′,2″-terpyridin-4′-yl)phenolate-κ3 N,N′,N″-κO]dimanganese(II), respectively. Face-to-face π–π stacking interactions between the pyridine rings play a crucial role in supramolecular networks of both complexes. Both complexes display weaker photoluminescence than the free ligand and the dinuclear complex luminescence was stronger than the mononuclear one. 相似文献
983.
《Journal of Coordination Chemistry》2012,65(2):244-255
A series of new coordination compounds with 1-carboxymethylpyridinium-4-benzoate (L) and transition metal ions have been synthesized. They are formulated as [M(L)2(H2O)4]?·?4H2O M=Mn (1) and Co (2), {[M(L)2]?·?xH2O} n M=Mn, x?=?1 (3); M=Co, x?=?2 (4), and M=Cu, x?=?3 (5). In 1 and 2, the zwitterionic dicarboxylate ligand is monodentate through only one carboxylate to generate mononuclear molecules. The molecules are assembled through O–H?···?O interactions to give 3-D pillared layer-like architectures, in which interesting 1-D tape-like hydrogen bonding motifs are connected into 2-D layers via carboxylate-mediated hydrogen bonds. In 3–5, the organic ligands serve as bridges with one carboxylate monodentate and the other chelating, and the metal ions are linked by double bridges to give 1-D polymeric chains, which are zigzag (3) or stair-like (4 and 5) due to the cis or trans coordination geometry around metal ions. The chains are further stabilized and associated into 3-D architectures through intra- and interchain hydrogen bonding and/or π–π stacking interactions. 相似文献
984.
《Journal of Coordination Chemistry》2012,65(6):1006-1015
Two new complexes, [Mn(H2bptc)(2,2′-bpy)2]?·?2H2O (1) and [Mn3(Hbptc)2(2,2′-bpy)3(H2O)8]?·?2H2O (2) (H4bptc?=?biphenyl-2,5,2′,5′-tetracarboxylic acid, 2,2′-bpy?=?2,2′-bipyridine), have been synthesized under hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, powder X-ray diffraction, and thermogravimetric analyses. Complexes 1 and 2 are both linked into 3-D supramolecular networks by non-covalent interactions (O–H?···?O, C–H?···?O, C–H?···?π, and π?···?π). Complexes 1 and 2 exhibit weak antiferromagnetic interactions. 相似文献
985.
《Journal of Coordination Chemistry》2012,65(9):1021-1027
A three-dimensional supramolecular compound [Mn(N3)2(H2O)3(hmt)] 2 , where hmt stands for hexamethylenetetramine, was synthesized and characterized by IR, crystal structure and magnetic susceptibility. The compound [Mn(N3)2(H2O)3(hmt)] n , crystallizes in the orthorhombic system, space group Pn 21 a, with a = 6.5201(9), b = 9.322(2), c = 22.192(3) Å, β = 90° and Z = 2. The Mn atom is coordinated in an octahedral arrangement by three nitrogen atoms from three azido ions, and three oxygen atoms from three water molecules, respectively. The azide ligand bridges Mn atoms in μ-1,3 fashion, forming a zigzag chain. Hmt connected with the zigzag chain by hydrogen bonds, to form a three-dimensional supramolecular structure. The magnetic susceptibility data show that there is an antiferromagnetic exchange interaction in the title compound. The data were modeled using an infinite chain model leading to J = -4.8 cm?1. 相似文献
986.
《Journal of Coordination Chemistry》2012,65(18):1681-1687
A two-dimensional coordination polymer, [Mn(Enox)2]·4H2O, 1 (H-Enox?=?1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-pierazinyl)-1,8-naphtyridine-3-carboxylic acid), has been rationally designed and synthesized under hydrothermal conditions. Compound 1 is self-assembled from bifunctional drug ligand enoxacin and transition metal ion Mn(II) through covalent coordination bonds and hydrogen bondings. 相似文献
987.
《Journal of Coordination Chemistry》2012,65(11):1263-1270
Two novel manganese(II) complexes, [Mn(phen)2N3·H2O]ClO4·H2O and Mn(phen)2(N3)2 have been synthesized by the reaction of Mn(ClO4)2·6H2O and Mn(CH3CO2)2·4H2O with NaN3 and phen in EtOH/H2O solution, respectively (where phen = 1,10-phenanthroline). Their crystal structures have been determined by X-ray diffraction. Both complex molecules have distorted octahedral geometry and two 1,10-phenanthroline molecules chelate to a Mn(II) atom with a cis-configuration. To [Mn(phen)2N3·H2O]ClO4·H2O, one nitrogen atom from an azide anion and one oxygen atom from a water molecule cis-coordinate to the Mn(II) atom while two nitrogen atoms occupy cis positions in Mn(phen)2(N3)2. These complexes are versatile precursors for the design of heteropolymetallic systems. 相似文献
988.
《Journal of Coordination Chemistry》2012,65(7):1144-1157
Manganese(III)tetraphenylporphyrin supported on multi-wall carbon nanotubes (MWCNTs) were developed as efficient catalysts for epoxidation of alkenes with sodium periodate under mild conditions. The catalysts were prepared by axial ligation of manganese to 2-aminobenzimidazole and 2-aminothiazole preanchored to MWCNTs. The formation of these heterogenized catalysts was followed using elemental analysis, FT-IR spectroscopy, diffuse reflectance UV-Vis spectrophotometry, and scanning electron microscopy. The reactivity of these catalysts under both magnetic stirring and ultrasonic irradiation and also their reusability were investigated. 相似文献
989.
《Journal of Coordination Chemistry》2012,65(1):11-16
The title complex has been prepared by the reaction of Mn(2,2'-bipy)Cl 2 with 1,3-benzenedicarboxylate (BDC) in ethanol solution. The complex crystallizes in space group C 2/ c with a =13.847(6), b =15.629(7), c =17.106(6) Å, g =107.90(3)° and z =8. Three BDC and one bipy ligands coordinate to Mn(II) to form a distorted octahedron. Each BDC bridges three Mn(II) atoms to form a polymeric chain. It is notable that although the Mn(II) atom deviates 1.084 Å from the bridging carboxyl plane it still has a normal coordination distance of 2.141(2) Å. This might suggest an electrostatic interaction between Mn(II) and carboxyl O atoms in the title complex. The IR spectrum is discussed, based on the molecular structure. 相似文献
990.
《Journal of Coordination Chemistry》2012,65(19):3126-3133
A chain-like compound of [Mn(salpn)][Fe(bipy)(CN)4] (1) (salpn = N,N′-propylenebis(salicylideneiminato)dianion; bipy = 2,2′-bipyridine), assembled from building blocks of [Fe(bipy)(CN)4]? and [Mn(salpn)]+, has been characterized by elemental analyses, ICP, IR, thermoanalysis, single crystal X-ray structure analysis and magnetic measurements. In 1, each [Fe(bipy)(CN)4]? anion coordinates with two [MnIII(salpn)]+ cations via two trans-CN? groups, and each [MnIII(salpn)]+ cation is axially coordinated by two [Fe(bipy)(CN)4]? ions, resulting in a straight 1-D chain. The chains stack via aromatic π–π-type interactions. Magnetic studies reveal the presence of weak antiferromagnetic interactions between adjacent FeIII and MnIII ions through cyanide-bridges. 相似文献