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991.
Liliana Cseh Carol Csunderlik Ingo Pantenburg Gerd Meyer Otilia Costisor 《无机化学与普通化学杂志》2003,629(6):985-988
The complex Co(C14H13NO)2Cl2 with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl2·6H2O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co2+ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed. 相似文献
992.
CoSm(SeO3)2Cl, CuGd(SeO3)2Cl, MnSm(SeO3)2Cl, CuGd2(SeO3)4 and CuSm2(SeO3)4: Transition Metal containing Selenites of Samarium and Gadolinum The reaction of CoCl2, Sm2O3, and SeO2 in evacuated silica ampoules lead to blue single crystals of CoSm(SeO3)2Cl (triclinic, , Z = 4, a = 712.3(1), b = 889.5(2), c = 1216.2(2) pm, α = 72.25(1)°, β = 71.27(1)°, γ = 72.08(1)°, Rall = 0.0586). If MnCl2 is used in the reaction light pink single crystals of MnSm(SeO3)2Cl (triclinic, , Z = 2, a = 700.8(2), b = 724.1(2), c = 803.4(2) pm, α = 86.90(3)°, β = 71.57(3)°, γ = 64.33(3)°, Rall = 0.0875) are obtained. Green single crystals of CuGd2(SeO3)2Cl (triclinic, , Z = 4, a = 704.3(4), b = 909.6(4), c = 1201.0(7) pm, α = 70.84(4)°, β = 73.01(4)°, γ = 70.69(4)°, Rall = 0.0450) form analogously in the reaction of CuCl2 and Gd2O3 with SeO2. CoSm(SeO3)2Cl contains [CoO4Cl2] octahedra, which are connected via one edge and one vertex to infinite chains. The Mn2+ ions in MnSm(SeO3)2Cl are also octahedrally coordinated by four oxygen and two chlorine ligands. The linkage of the polyhedra to chains occurs exclusively via edges. Both, the cobalt and the manganese compound show the Sm3+ ions in eight and ninefold coordination of oxygen atoms and chloride ions. In CuGd(SeO3)2Cl the Cu2+ ions are coordinated by three oxygen atoms and one Cl— ion in a distorted square planar manner. One further Cl— and one further oxygen ligand complete the [CuO3Cl] units yielding significantly elongated octahedra. The latter are again connected to chains via two common edges. For the Gd3+ ions coordination numbers of ?8 + 1”? and nine were found. Single crystals of the deep blue selenites CuM2(SeO3)4 (M = Sm/Gd, monoclinic, P21/c, a = 1050.4(3)/1051.0(2), b = 696.6(2)/693.5(1), c = 822.5(2)/818.5(2) pm, β = 110.48(2)°/110.53(2)°, Rall = 0.0341/0.0531) can be obtained from reactions of the oxides Sm2O3 and Gd2O3, respectively, with CuO and SeO2. The crystal structure contains square planar [CuO4] groups and irregular [MO9] polyhedra. 相似文献
993.
CompoundsformedfromCu ,AgandAuwithdithio lateligands ,suchasthedialkyldithiocarbamate (DTC) ,mercaptothiazoline (HMT)anddialkyldithiophosphates(DDP) ,haveplayedanimportantroleintechnology .1Cu(I) Sclustersalsohavebeenimplicatedinbiologyasan ti oxidants .2Thecuban… 相似文献
994.
995.
A New High Temperature Form of TiO: H? TiO Single crystals of a high temperature form of TiO (H? TiO) were prepared above 3 000°C by CO2-LASER technique. They crystallize with a hitherto unobserved crystal structure of oxides with titanium in the oxidation state two, isotypic to tungsten carbide with Ti2+ in a trigonal prismatic surrounding by oxygen. Space group D–P6 m2, a = 3.0310, c = 3.2377 Å, Z = 1. 相似文献
996.
Michael Ruck 《无机化学与普通化学杂志》1994,620(10):1832-1836
Preparation and Crystal Structure of the First Polymeric Phosphorus Selenide catena-(P4Se4)x Catena-(P4Se4)x was prepared in crystalline form from the elements using iodine as a catalyst, and characterized by means of X-ray diffraction and IR spectroscopy. Single-crystal investigations (space group P21/c, a = 1 119.2(3), b = 728.2(2), c = 1 142.5(3) pm, β = 115.91(2)°, V = 837.5(7) · 106 pm3) revealed parallel chains of P4Se3 hetero-norbornane units linked via Se atoms. Thus, being the first phosphorus selenide which does not contain discrete molecules, catena-(P4Se4)x can be regarded as a polymeric form of α-P4Se4 or as a crystalline modification of vitrous phosphorus selenide. 相似文献
997.
Green Bis-(2-iminoisopropyl-thiophenolato)nickel(II) and other Similar NiII Complexes The compounds [NiII(iitp)2] 1 (iitp = 2-iminoisopropyl-thiophenolate), [Ni(imptp)2] · 2 CH3OH 2 , a dinuclear compound with an Ni? Ni distance of 276 pm, and [PPh4] · [NiII(imptp)(SCN)] 3 (imptp = 2-(2-iminopentane-4-on)-thiophenolate) have been prepared by the reaction of nickel(II)-acetate-tetrahydrate with 2-iminoisopropyl-thiophenole and 2-(2-iminopentane-4-on)-thiophenole in methanol, respectively. They have been characterized by single-crystal X-ray structure analysis and other physical methods. The redox behaviour of 1–3 has been studied in detail (chemically as well as by cyclovoltammetry and ESR spectroscopy). Particularly interesting are the electronic properties of 1 and its reduction with NaBH4 and the following reaction of the product with O2. The complexes are model compounds for some Ni-containing enzymes. For details of the crystal structure determination see “Inhaltsübersicht”. 相似文献
998.
Montserrat Barquín María J. Gonzlez Garmendia Liher Larrínaga Elena Pinilla María R. Torres 《无机化学与普通化学杂志》2005,631(11):2210-2214
The complexes of copper formato with pyrazine and dimethylpyrazines: Cu(HCOO)2(pyrz) ( 1 ), Cu2(HCOO)4(pyrz) ( 2 ), Cu2(HCOO)4(2,3‐Me2pyrz) ( 3 ), Cu2(HCOO)4(2,5‐Me2pyrz) ( 4 ), and Cu2(HCOO)4(2,6‐Me2pyrz)2 ( 5 ) have been synthesized and characterized by chemical analysis and IR and electronic spectro scopies. The three‐dimensional structure of compound 1 consists of –Cu–pyrz–Cu–pyrz– chains joined by bridging formate groups coordinated, in configuration syn‐anti, to two copper atoms. The coordination around the copper atom is orthorhombic with two Cu–O distances of 2.374(1) Å, two Cu–O of 1.952 Å and two Cu–N of 2.080 Å. Compound 5 is formed by molecular dimers with the [Cu2(μ‐HCOO)4] unit, two copper atoms and four syn‐syn fomate groups, and two ligands coordinated to the copper atoms in the axial positions. In compounds 2 and 3 chains of [Cu2(μ‐HCOO)4] dimers with pyrz or 2,3‐Me2pyrz as bridging ligands are formed. The EPR signal of 1 is orthorhombic (g = 2.23, 2.20 and 2.06). In the EPR spectra of 2 – 5 compounds the triplet (S = 1) signals are observed. The g?, g∥ and D values are been calculated. 相似文献
999.
CeO2—LnO1.5固溶体的表征及其甲烷催化燃烧性能 总被引:3,自引:0,他引:3
向CeO2中引入Ln3 离子后形成的CeO2-LnO1.5(Ln=La,Nd,Sm,Gd)固溶体(n(Ce):n(Ln)=1:1)是一种无贵金属的新型高效甲烷燃烧催化剂.比表面、XRD、Raman、TEM等分析证实,这类固溶体具有部分畸变的萤石结构,Ln3 进入晶格后诱发的结构变化使得团溶体的表面和本体能同时参与氧化还原反应.实验表明,该固态溶液体系是甲烷催化燃烧的良好催化剂. 相似文献
1000.
The hexamolybdenum cluster complex [Mo6(3-Cl)8(O2CMe)6]2–, 1 was isolated as the Bu4N+ salt in 71% yield from the reaction of (Bu4N)2[Mo6(3-Cl)8Cl6] with AgO2CMe in CH2Cl2 solvent. The compound was characterized by single crystal X-ray diffraction analysis. The cluster contains an octahedral arrangement of six molybdenum atoms with eight chloride ligands bridging the eight trianglar faces and six carboxylate ligands terminally coordinated through one oxygen atom to each of the six molybdenum atoms. Crystal data: space group =P21/n,a=10.713(3)Å,b=14.43(1)Å,c=21.919(4)Å, =94.37(2)°,Z=2, 1965 reflections,R=0.036. 相似文献