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241.
Metehan C. Turhan Robert P. Lynch Himendra Jha Patrik Schmuki Sannakaisa Virtanen 《Electrochemistry communications》2010,12(6):796-799
In the present work we show that self-ordered nanotubular and nanoporous magnesium oxy-fluoride structures can be grown on a magnesium-based alloy when anodized in a non-aqueous (ethylene glycol) HF electrolyte. The morphology of the surface structures varies with applied potential and anodisation time. Tubular and porous structures with different sizes and orientation can be grown. 相似文献
242.
243.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e588-e588
The structure of the title compound, C14H12ClNO2, (I), comprises essentially planar molecules which crystallize in a monoclinic lattice. C—H?O interactions exist to both naphthoquinone O atoms and the Cl atom. 相似文献
244.
M. A. Pedrosa C. Hidalgo A. López-Fraguas B. Ph. Van Milligen R. Balbín J. A. Jiménez E. Sánchez J. Castellano TJ-II Team L. García B. A. Carreras V. E. Lynch 《Czechoslovak Journal of Physics》2000,50(12):1463-1470
It has been shown that transport barriers in toroidal magnetically confined plasmas tend to be linked to regions of unique
magnetic topology such as the location of a minimum in the safety factor, rational surfaces or the boundary between closed
and open flux surfaces. In the absence ofE×B sheared flows, fluctuations are expected to show maximum amplitude near rational surfaces, and plasma confinement might tend
to deteriorate. On the other hand, if the generation ofE×B sheared flows were linked to low order rational surfaces, these would be beneficial for confinement. Experimental evidence
ofE×B sheared flows linked to rational surfaces has been obtained in the plasma edge region of the TJ-II stellarator.
Presented at the Workshop on the Role of Electric Fields in Plasma Confinement and Exhaust, Budapest, 18–19 June, 2000. 相似文献
245.
Will E. Lynch Clifford W. Padgett Brandon Quillian John Haddock 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(4):298-300
The cationic pseudo‐square‐planar complex tetrakis(1‐methyl‐2,3‐dihydro‐1H‐imidazole‐2‐thione‐κS)gold(III) trichloride sesquihydrate, [Au(C4H6N2S)4]Cl3·1.5H2O, was isolated as dark‐red crystals from the reaction of chloroauric acid trihydrate (HAuCl4·3H2O) with four equivalents of methimazole in methanol. The AuIII atoms reside at the corners of the unit cell on an inversion center and are bound by the S atoms of four methimazole ligands in a planar arrangement, with S—Au—S bond angles of approximately 90°. 相似文献
246.
Andrew G. Tennyson Dr. Robert J. Ono Todd W. Hudnall Dr. Dimitri M. Khramov Dr. Joyce A. V. Er Justin W. Kamplain Dr. Vincent M. Lynch Dr. Jonathan L. Sessler Prof. Christopher W. Bielawski Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(1):304-315
Reaction of bromanil with N,N′‐dimesitylformamidine followed by deprotonation with NaN(SiMe3)2 afforded 1,1′,3,3′‐tetramesitylquinobis(imidazolylidene) ( 1 ), a bis(N‐heterocyclic carbene) (NHC) with two NHC moieties connected by a redox active p‐quinone residue, in 72 % yield of isolated compound. Bimetallic complexes of 1 were prepared by coupling to FcN3 ( 2 ) or FcNCS ( 3 ; Fc=ferrocenyl) or coordination to [M(cod)Cl] ( 4 a or 4 b , where M=Rh or Ir, respectively; cod=1,5‐cyclooctadiene). Treatment of 4 a and 4 b with excess CO(g) afforded the corresponding [M(CO)2Cl] complexes 5 a and 5 b , respectively. Analysis of 2 – 5 by NMR spectroscopy and X‐ray diffraction indicated that the electron‐deficient quinone did not significantly affect the inherent spectral properties or coordination chemistry of the flanking imidazolylidene units, as compared to analogous NHCs. Infrared spectroscopy and cyclic voltammetry revealed that decreasing the electron density at MLn afforded an increase in the stretching energy and a decrease in the reduction potential of the quinone, indicative of metal–quinone electronic interaction. Differential pulse voltammetry and chronoamperometry of the metal‐centered oxidations in 2 – 4 revealed two single, one‐electron peaks. Thus, the metal atoms bound to 1 are oxidized at indistinguishable potentials and do not appear electronically coupled. However, the metal–quinone interaction was used to increase the electron density at coordinated metal atoms. Infrared spectroelectrochemistry revealed that the average νCO values for 5 a and 5 b decreased by 14 and 15 cm?1, respectively, upon reduction of the quinone embedded within 1 . These shifts correspond to 10 and 12 cm?1 decreases in the Tolman electronic parameter of this ditopic ligand. 相似文献
247.
Kaliyaperumal Thanigaimani Annamalai Subashini Packianathan Thomas Muthiah Daniel E. Lynch Ray J. Butcher 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(2):o42-o45
In the crystal structures of 2‐amino‐4,6‐dimethoxypyrimidinium 2,4,6‐trinitrophenolate (picrate), C6H10N3O2+·C6H2N3O7−, (I), and 2,4‐diamino‐5‐(4‐chlorophenyl)‐6‐ethylpyrimidin‐1‐ium (pyrimethaminium or PMN) picrate dimethyl sulfoxide solvate, C12H14ClN4+·C6H2N3O7−·C2H6OS, (II), the 2‐amino‐4,6‐dimethoxypyrimidine and PMN cations are protonated at one of the pyrimidine N atoms. The picrate anion interacts with the protonated cations through bifurcated N—H...O hydrogen bonds, forming R21(6) and R12(6) ring motifs. In (I), Z′ = 2. In (II), two inversion‐related PMN cations are connected through a pair of N—H...N hydrogen bonds involving the 4‐amino group and the uncharged N atom of the pyrimidine ring, forming a cyclic hydrogen‐bonded R22(8) motif. In addition to the pairing, the O atom of the dimethyl sulfoxide solvent molecule bridges the 2‐amino and 4‐amino groups on both sides of the paired bases, resulting in a self‐complementary …DADA… array of quadruple hydrogen‐bonding patterns. 相似文献
248.
Yang XP Jones RA Wong WK Lynch V Oye MM Holmes AL 《Chemical communications (Cambridge, England)》2006,(17):1836-1838
The use of the Schiff-base ligand N,N'-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine (H2L) and 1,4-benzenedicarboxylate (BDC) enables the construction of the hexanuclear luminescent Zn-Nd complex [Zn4Nd2L4(1,4-BDC)2].[Nd(NO3)5(H2O)].Et2O.2EtOH.3H2O. 相似文献
249.
Sessler JL Cho DG Stepień M Lynch V Waluk J Yoon ZS Kim D 《Journal of the American Chemical Society》2006,128(39):12640-12641
The synthesis of an inverted, methoxylated sapphyrin derivative is described. This system, wherein inversion of pyrrolic nitrogen atoms is configurationally enforced via the use of a 3,3'-bipyrrolic precursor, displays what is best described as "weak aromaticity" as judged from its spectroscopic features and supporting theoretical calculations. 相似文献
250.
Král V Lang K Králová J Dvorák M Martásek P Chin AO Andrievsky A Lynch V Sessler JL 《Journal of the American Chemical Society》2006,128(2):432-437
Enhanced hydrolysis rates for the cleavage of bis(4-nitrophenyl)phosphate (BNPP), a model phosphodiester, may be achieved by using appropriately designed ditopic receptors containing the known phosphate-binding nucleus, sapphyrin, attached covalently to suitably oriented polyhydroxyl subunits. Evidence for the interaction between sapphyrin and BNPP comes from solid-state X-ray diffraction analysis of a diprotonated dihydroxylated sapphyrin-BNPP complex and from solution-phase (31)P NMR spectroscopic binding studies. The sapphyrins described in this paper may have a role to play as oligonucleotide cleavage agents. 相似文献