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161.
Stabilization of M+ Ions (M = In, Tl) by Dibenzyldichlorogallate MCl reacts with (PhCH2)2GaCl to give M[(PhCH2)2GaCl2] [M = In ( 1 ), Tl ( 2 )]. 1 and 2 were characterized by NMR, IR and MS techniques. In addition, an X‐ray structure determination of 1 was performed. According to this, 1 consists of four‐membered In2Cl2 rings connected by weak In…Cl contacts (344 pm) along [010] to a coordination polymer. The In+ ion is coordinated by four In–Cl and two In‐aryl interactions.  相似文献   
162.
Two new non‐metallic filled β‐manganese phases M2Ga6Te10 (M: Li, Na) are obtained as black, homogeneous, microcristalline samples as well as single crystals by direct reaction of the elements. According to the single crystal structure determinations both compounds crystallize in space group R32 (No. 155, Z = 2) with the lattice constants: a = 1436.9(2), c = 1759.0(4) pm (T = 180 K, Li2Ga6Te10) and a = 1458(1) pm, c = 1776.1(4) pm (T = 290 K, Na2Ga6Te10). Their structures are characterized by tetrahedral close packings of Te2–, corresponding to the arrangement of Mn atoms in β‐Mn. While Ga3+ ions are distributed in an ordered way over 12% of the tetrahedral holes, the M+ ions occupy all distorted octahedral (“metaprismatic”) holes. As the Li+ ions are too small they occupy off‐center positions inside the metaprisms. Positions with the strongest off‐centering can only be refined on the basis of a split model. MAS‐NMR measurements, including multiple quantum NMR, allowed the two different crystallographic M+ sites to be distinguished unambigously by separate 7Li and 23Na signals, respectively. The assignment of the NMR signals was supported by measurements of samples in which Li+ was partly substituted by larger cations (Sn2+, Pb2+).  相似文献   
163.
Preparation, Properties, and Molecular Structures of Dimethylaminomethyl Ferrocenyl Compounds of selected Elements of Group 13 and 14 Dimethylmetalchlorides of gallium and indium react with dimethylaminomethylferrocenyllithium (FcNLi) to give the corresponding dimethylmetaldimethylaminomethylferrocenes 1 and 2 [Me2MFcN; M=Ga, In]. In a similar manner dialkylmetaldichlorides of germanium and tin yield the expected chlordialkylmetaldimethylaminomethylferrocenes 3 – 5 [R2(Cl)MFcN; M=Ge; R = Me ( 3 ), M=Sn; R=Me ( 4 ), Ph ( 5 )]. In a reaction of Me3Al and Me2AlCl with dimethylaminomethylferrocene the formation of the 1 : 1 adducts 7 and 8 could be observed. All compounds were characterised by 1H and 13C nmr spectroscopy. The molecular structures of 1 , 3 , 4 and 7 were determined. 3 and 4 build in contrast to 1 monomeric molecules with chelat rings as a result of the M–N coordination. Compound 7 consist of monomeric molecules with 4 coordinated Al atoms.  相似文献   
164.
The Courses of the Ammonolyses of the Ammonium Hexafluorometalates of Aluminum, Gallium, and Indium, (NH4)3MF6 (M = Al, Ga, In) The courses of the ammonolysis reactions of the ammonium hexafluorometalates (NH4)3MF6 (M = Al, Ga, In) were investigated with the aid of in‐situ powder diffractometry and differential thermal analysis. Under these conditions, the reaction of (NH4)3AlF6 with gaseous ammonia yields at about 360 °C AlF3 via the intermediates NH4AlF4, Al(NH3)2F3 and Al(NH3)F3. The ammonolysis of (NH4)3GaF6 produces GaN at about 400 °C. Depending upon the actual reaction conditions, the intermediates NH4GaF4 and Ga(NH3)F3 as well as their ammonia adducts NH4GaF4 · NH3 and Ga(NH3)2F3 and the amide‐ammoniate Ga(NH3)(NH2)F2 are observed. In the case of (NH4)3InF6 the intermediates (NH4)3InF6 · NH3 and In(NH3)F3 may exist; there are also indications for the reduction of In(III) to In(I) and for the existence of In(NH3)2F and InF as products of the ammonolysis of (NH4)3InF6.  相似文献   
165.
本文中,对吸附于纳米磷化镓(GaP)粉体表面的碱性品红拉曼光谱进行了研究。通过将吸附碱性品红与纯碱性品红晶体样品的拉曼光谱进行对比、分析可知,碱性品红在纳米GaP粉体表面发生了化学吸附。在吸附碱性品红样品的拉曼光谱中,位于1200~1320cm-1范围内的光谱特征表明可能有新的化学键(P-O-C+或Ga-O-C+)形成。碱性品红分子的中央碳正离子(C+)与GaP表面具有孤对电子的氧原子形成配位键。红外光谱结果表明,氧原子与纳米GaP粉体表面的磷原子或镓原子键合,以P-O,Ga-O或P-O-Ga形式存在于GaP表面。碱性品红分子的呼吸振动,N-苯环伸缩振动,以及苯环C-C伸缩振动散射强度与纯碱性品红晶体样品相比皆有所增强。N-苯环伸缩振动散射强度增加意味着N原子是除C+离子以外的另一个可以与GaP表面发生化学作用的活性中心,这种化学作用是由N原子与GaP表面存在共轭效应造成的。  相似文献   
166.
Reactions of R4Sb2 (R = Me, Et) with (Me3SiCH2)3M (M = Ga, In) and Crystal Structures of [(Me3SiCH2)2InSbMe2]3 and [(Me3SiCH2)2GaOSbEt2]2 The reaction of (Me3SiCH2)3In with Me2SbSbMe2 gives [(Me3SiCH2)2InSbMe2]3 ( 1 ) and Me3SiCH2SbMe2. [(Me3SiCH2)2GaOSbEt2]2 ( 2 ) is formed by the reaction of (Me3SiCH2)3Ga with Et2SbSbEt2 and oxygen. The syntheses and the crystal structures of 1 and 2 are reported.  相似文献   
167.
Classical and nonclassical can be used to describe the bonding in the polyhedral Ga4Si framework of the silagallanate ion [Me3SiSi{GaSi(SiMe3)3}3GaSiMe3] (the GaSi framework is depicted in the picture). This is the result of density functional calculations that were carried out on model compounds. The cluster was obtained by ultrasonication of gallium and iodine and subsequent reaction with (Me3Si)3Li(thf)3.  相似文献   
168.
About the Effect of Substitution on the Crystal Structure of SrNi2P2 With several series of mixed crystals the effect of substitution on the crystal structure of SrNi2P2 (polymorphic, the structures are variants of the ThCr2Si2 type) is investigated by X-ray methods. In the compound Ni completely can be substituted by Co and Cu respectively and also P by As; in Sr1–xCaxNi2P2 there is a gap of the miscibility between 0.3 ≤ x ≤ 0.6. A low substitution of the several elements more than proportionally changes the structure parameters. In this range the mixed crystals with Ca, Cu, and As, respectively, undergo first order phase transitions with significant changes of the bond distances, which will be interpreted by the results of band structure calculations.  相似文献   
169.
Sesquialkoxides of Gallium and Indium Treatment of GaMe3 with one equivalent of HOcHex in toluene at 20 °C leads to [Me2GaOcHex]2 ( 4 ) under evolution of methane. The reaction of InMe3 with two equivalents of HOcHex leads under similar conditions not to [MeIn(OcHex)2]n but to the sesquialkoxide [In{Me2In(OcHex)2}3] ( 5 ). 5 can be described also as [{Me2InOcHex)}2{MeIn(OcHex)2}2]. The use of an excess of cyclohexanol in boiling toluene gives the same result. Under these reflux conditions, the reaction of GaMe3 with an excess of PhCH2OH leads exclusively to another type of sequialkoxides, [Ga{MeGa(OCH2Ph)3}3] ( 6 ). 4 — 6 were characterized by NMR, vibrational and MS spectra, as well as by X‐ray structure determinations. According to this, 4 forms centrosymmetrical and therefore planar Ga2O2 four‐membered rings. 5 and 6 possess basically the same structural motif, central M3+ ion ( 5 : In3+; 6 : Ga3+) coordinated by three metalate units ( 5 : [Me2In(OcHex)2]; 6 : [MeGa(OCH2Ph)3]). The central M3+ ions have always coordination number (CN) six while the three surrounding metal ions possess CN 4. Because of the spectroscopic findings 6 must exist in two isomers (1:1). The C3‐symmetrical isomer C3‐ 6 was characterized by X‐ray analysis, while the isomer C1‐ 6 could by described mainly by the complex NMR data.  相似文献   
170.
Chemical Vapor Transport of Solid Solutions. 11 Mixed Phases and Chemical Vapor Transport in the Systems CrIII/InIII/GeIV/O, GaIII/InIII/GeIV/O, MnIII/InIII/GeIV/O und FeIII/InIII/GeIV/O By means of chemical vapor transport methods the following mixed phases have been prepared: Cr0, 18In1, 82Ge2O7 (Cl2, 950 → 850 °C), (Ga0, 6In1, 4)2Ge2O7 (Thortveitit‐type, Cl2, 1050 → 950 °C), (Ga1, 9In0, 1)2Ge2O7 (Ga2Ge2O7‐type, 1050 → 950 °C), (In1, 9Mn0, 1)2Ge2O7 (Thortveiti‐type, Cl2, 1000 → 800 °C), mixed phase crystallizing in the Mn2Ge2O7‐structure showing a composition near MnInGe2O7 (Cl2, 1000 → 800 °C), Mn6, 5In0, 5GeO12 (Braunit‐type, Cl2, 1000 → 800 °C), (FexIn1‐x)Ge2O7 (Thortveitit‐type with x = 0…0, 94; Cl2, 840 → 780 °C). Changing the compositions of the starting materials showed no effect on the composition of the deposit except for the system Fe2O3‐In2O3‐GeO2.  相似文献   
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