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61.
Piskunov AV Mescheryakova IN Fukin GK Baranov EV Hummert M Shavyrin AS Cherkasov VK Abakumov GA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(32):10085-10093
Oxidation of tin(IV) o-amidophenolate complexes [Sn(ap)Ph(2)] (1) and [Sn(ap)Et(2)(thf)] (2) (ap=dianion of 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-iminobenzoquinone (ImQ)) with molecular oxygen and sulfur in toluene solutions was investigated. The reaction of oxygen with 1 at room temperature forms a paramagnetic derivative [Sn(isq)(2)Ph(2)] (3) (isq=radical anion of ImQ) and diphenyltin(IV) oxide [{Ph(2)SnO}(n)]. Interaction of 1 with sulfur gives another monophenyl-substituted paramagnetic tin(IV) complex, [Sn(ap)(isq)Ph] (4), and the sulfide, [Ph(3)Sn](2)S. The oxidation of 2 with oxygen and with sulfur proceeds through the derivative [Sn(isq)(2)Et(2)] (7), which undergoes alkyl elimination to give two new tin(IV) compounds, [Sn(ap)(isq)Et] (5) and [Sn(ap)(EtImQ)Et] (6) (EtImQ=2,4-di-tert-butyl-6-(2,6-diisopropylphenylimino)-3-ethylcyclohexa-1,4-dienolate ligand), respectively, along with the corresponding alkyltin(IV) oxide and sulfide. Complexes 3-5 and 7 were studied by EPR spectroscopy. The structures of 3, 4 and 6 were investigated by X-ray analysis. 相似文献
62.
Yu. A. Kurskii N. O. Druzhkov A. N. Egorochkin G. A. Abakumov 《Russian Journal of General Chemistry》2016,86(1):37-42
The effect of substituents in the reactions of 3,6-di-tert-butyl-о-benzoquinone with organozinc and organocadmium compounds, leading to three types of products: 3-alkyl-6-tert-butyl-о-benzoquinones, 4-alkyl-3,6-di-tert-butyl-о-benzoquinones, and 2-alkoxy-(or 2-phenoxy)-3,6-di-tert-butylphenols. Correlation analysis gave evidence to show that the first- and second-type products are formed by nucleophilic 1,2- and 1,4-addition, while substituted phenols result from single-electron transfer. 相似文献
63.
G. N. Mazo S. N. Savvin A. M. Abakumov J. Hadermann Yu. A. Dobrovol’skii L. S. Leonova 《Russian Journal of Electrochemistry》2007,43(4):436-442
Samples of lanthanum-strontium cuprate LaSrCuO3.61 are synthesized by a solid-phase method at 1473 K, in air. Electron diffraction patterns reveal low-intensity satellites whose position is described in the reciprocal space by the (3 + 2)-dimensional space group I4/mmm(αα0, α-α0)00mg. Using a five-layer cell LaSrCuO4-δ|YSZ|LaSrCuO4-δ|YSZ|LaCuO4-δ prepared by isostatic hot pressing, the ionic component of conductivity of LaSrCuO4-δ is determined (σ1179 K = 3.8 × 10?3 S cm?1), which is commensurate with other mixed conductors based on complex oxides of cobalt and iron. 相似文献
64.
A. V. Lado A. V. Piskunov V. K. Cherkasov G. K. Fukin G. A. Abakumov 《Russian Journal of Coordination Chemistry》2006,32(3):173-179
The reactions of sodium and thallium catecholates CatM2 (Cat is the 3,6-di-tert-butylpyrocatechol dianion; M = Na, T1) with tin diphenyl dichloride afford new tin catecholate complexes Ph2SnCat · THF (I) and Ph2SnCat (II). The molecular structure of pentacoordinated complex I is determined by X-ray diffraction analysis. The synthesized complexes are capable of fixating both short-lived (PhC(O)O., (CH3)2NC(S)S., and NC(CH3)2C.) and stable free radicals (aroxyl, nitroxyl, triphenylmethyl, and phenoxazinyl) to form stable o-semiquinone tin derivatives. 相似文献
65.
Leonid N. Bochkarev Vladislav I. Scherbakov Irina P. Malysheva Galina V. Basova Natalia E. Stolyarova Irina K. Grigorieva Andrey L. Bochkarev Georgii K. Fukin Yurii A. Kurskii Gleb A. Abakumov 《Journal of organometallic chemistry》2006,691(5):983-986
The novel silicon-, germanium- and tin-containing imido alkyl complexes of tungsten of the type (ArN)2W(CH2EMe3)2 (; E = Si (1), Ge (2), Sn (3)) have been prepared by the reactions of (ArN)2WCl2(dme) (dme = 1,2-dimethoxyethane) with heteroelement-containing alkyllithium or Grignard reagents Me3ECH2Li (E = Si, Ge), Me3ECH2MgCl (E = Ge, Sn). The title compounds were isolated in high yields as crystalline solids and characterized by elemental analysis, IR, 1H, 13C, 29Si and 119Sn NMR spectroscopy and X-ray diffraction studies. The geometry of the W atoms in the compounds can be described as a distorted tetrahedron. 相似文献
66.
Artem M. Abakumov Marta D. Rossell Sergey Yu. Vassiliev Gustaaf Van Tendeloo 《Journal of solid state chemistry》2006,179(2):421-428
Phase transitions in the elpasolite-type K3AlF6 complex fluoride were investigated using differential scanning calorimetry, electron diffraction and X-ray powder diffraction. Three phase transitions were identified with critical temperatures , and . The α-K3AlF6 phase is stable below T1 and crystallizes in a monoclinic unit cell with a=18.8588(2)Å, b=34.0278(2)Å, c=18.9231(1)Å, β=90.453(1)° (a=2ac−cc, b=4bc, c=ac+2cc; ac, bc, cc—the basic lattice vectors of the face-centered cubic elpasolite structure) and space group I2/a or Ia. The intermediate β phase exists only in very narrow temperature interval between T1 and T2. The γ polymorph is stable in the T2<T<T3 temperature range and has an orthorhombic unit cell with a=36.1229(6)Å, b=17.1114(3)Å, c=12.0502(3)Å (a=3ac−3cc, b=2bc, c=ac+cc) at 250 °C and space group Fddd. Above T3 the cubic δ polymorph forms with ac=8.5786(4)Å at 400 °C and space group . The similarity between the K3AlF6 and K3MoO3F3 compounds is discussed. 相似文献
67.
A.M. Alekseeva A.M. Abakumov A. Leithe-Jasper Yu. Prots G. Van Tendeloo Yu. Grin 《Journal of solid state chemistry》2006,179(9):2751-2760
The new magnesium rhodium boron compound Mg8Rh4B has been synthesized by reaction of the metal powders with crystalline or amorphous boron or the RhB precursor. The crystal structure of Mg8Rh4B was solved using single-crystal X-ray diffraction data (space group , , Z=8, 174 reflections, RF=0.016). The crystal structure can be described as a filled Ti2Ni type where the interstitial sites 8b (), located at the center of two nested Mg4Rh4 tetrahedra, are occupied by boron atoms. Taking into account the absence of the Ti2Ni-type phase in the binary Mg-Rh system, the boron atoms can be considered as stabilizing this structural motif. From the bonding analysis with the electron localization function the crystal structure is described as covalently bonded [Rh4B]3− anions, embedded in a cationic magnesium matrix. 相似文献
68.
Effect of the solvent nature on the kinetics of photoreduction of 3,6-di-tert-butyl-1,2-benzoquinone and its six derivatives in the presence of N,N-dimethylaniline and 4-(N,N-dimethylamino)benzaldehyde has been investigated. It has been found that for the о-quinone—amine pair, for which the free energy change of electron transfer is ΔGe > +0.11 eV, the rate constant of о-quinone photoreduction kH decreases proportionally to the increase in the acceptor number of the solvent. For the о-quinone—amine pair with ΔGe < +0.11 eV, the kH value decreases proportionally to the increase in the donor number of the solvent. It has been established that the enhancement of the electron-acceptor properties of the solvent leads to the emergence of kinetic isotope effect for the reactant pairs of 3,6-di-tert-butyl-1,2-benzoquinone and 4,5-dimethoxy-3,6-di-tert-butyl-1,2-benzoquinone with N,N-di-methylaniline (ΔGe = +0.11 and +0.22 eV, respectively). 相似文献
69.
Li MR Adem U McMitchell SR Xu Z Thomas CI Warren JE Giap DV Niu H Wan X Palgrave RG Schiffmann F Cora F Slater B Burnett TL Cain MG Abakumov AM van Tendeloo G Thomas MF Rosseinsky MJ Claridge JB 《Journal of the American Chemical Society》2012,134(8):3737-3747
Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO(3) (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO(3) has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO(3). 相似文献
70.