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941.
Dr. Alba Gigante Eline Sijbesma Dr. Pedro A. Sánchez-Murcia Prof. Xiaoyu Hu Dr. David Bier Sandra Bäcker Prof. Shirley Knauer Prof. Federico Gago Prof. Christian Ottmann Prof. Carsten Schmuck 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5322-5325
We report on a stabilizer of the interaction between 14-3-3ζ and the Estrogen Receptor alpha (ERα). ERα is a driver in the majority of breast cancers and 14-3-3 proteins are negative regulators of this nuclear receptor, making the stabilization of this protein-protein interaction (PPI) an interesting strategy. The stabilizer ( 1 ) consists of three symmetric peptidic arms containing an arginine mimetic, previously described as the GCP motif. 1 stabilizes the 14-3-3ζ/ERα interaction synergistically with the natural product Fusicoccin-A and was thus hypothesized to bind to a different site. This is supported by computational analysis of 1 binding to the binary complex of 14-3-3 and an ERα-derived phosphopeptide. Furthermore, 1 shows selectivity towards 14-3-3ζ/ERα interaction over other 14-3-3 client-derived phosphomotifs. These data provide a solid support of a new binding mode for a supramolecular 14-3-3ζ/ERα PPI stabilizer. 相似文献
942.
Kristopher O. Davis Kaiyun Jiang Carsten Demberger Heiko Zunft Helge Haverkamp Dirk Habermann Winston V. Schoenfeld 《固体物理学:研究快报》2013,7(5):319-321
Emitter formation for industrial crystalline silicon (c‐Si) solar cells is demonstrated by the deposition of phosphorous‐doped silicate glasses (PSG) on p‐type monocrystalline silicon wafers via in‐line atmospheric pressure chemical vapor deposition (APCVD) and subsequent thermal diffusion. Processed wafers with and without the PSG layers have been analysed by SIMS measurements to investigate the depth profiles of the resultant phosphorous emitters. Subsequently, complete solar cells were fabricated using the phosphorous emitters formed by doped silicate glasses to determine the impact of this high‐throughput doping method on cell performance. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
943.
Kristopher O. Davis Kaiyun Jiang Marshall Wilson Carsten Demberger Heiko Zunft Helge Haverkamp Dirk Habermann Winston V. Schoenfeld 《固体物理学:研究快报》2013,7(11):942-945
Using a high throughput, in‐line atmosphere chemical vapor deposition (APCVD) tool, we have synthesized amorphous aluminum oxide (AlOx) films from precursors of trimethyl‐aluminum (TMA) and O2, yielding a maximum deposition 150 nm min–1 per wafer. For p‐type crystalline silicon (c‐Si) wafers, excellent surface passivation was achieved with the APCVD AlOx films, with a best maximum effective surface recombination velocity (Seff,max) of 8 cm/s following a standard industrial firing step. The findings could be attributed to the existence of large negative charge (Qf ≈ –3 × 1012 cm–2) and low interface defect density (Dit ≈ 4 × 1011 eV–1 cm–2) achieved by the films. This data demonstrates a high potential for APCVD AlOx to be used in high efficiency, low cost industrial solar cells. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
944.
Grünbaum introduced measures of symmetry for convex bodies that measure how far a given convex body is from a centrally symmetric one. Here, we introduce new measures of symmetry that measure how far a given convex body is from one with “enough symmetries”.To define these new measures of symmetry, we use affine covariant points. We give examples of convex bodies whose affine covariant points are “far apart”. In particular, we give an example of a convex body whose centroid and Santaló point are “far apart”. 相似文献
945.
N-Protected trifluoromethyl-substituted sulfoximines have been prepared by treatment of sulfonimidoyl fluorides with a combination of the Ruppert-Prakash reagent (TMSCF(3)) and tetrabutyl ammonium fluoride (TBAF). The starting materials were accessed following two synthetic routes, and for each reaction sequence the substrate scope was evaluated. Accordingly, a wide variety of aryl-substituted products were obtained in moderate to good yield. 相似文献
946.
A highly enantioselective Friedel-Crafts reaction catalyzed by a chiral phosphoric acid was developed. N-Boc-protected ethyl trifluoropyruvate imine was activated by 6 mol % of catalyst and reacted with a wide variety of indole derivatives to afford quaternary α-amino acids in excellent yields (up to 99%) and high enantioselectivities (up to 98:2 er). 相似文献
947.
The claim that N-mercapto-4-formylcarbostyril was isolated from Pseudomonas fluorescens strain G308 is questioned since N-thiols appear to be unstable compounds at ambient temperature. 相似文献
948.
Carsten Schultz 《Journal of Combinatorial Theory, Series A》2011,118(8):2291-2318
The stable Kneser graph SGn,k, n?1, k?0, introduced by Schrijver (1978) [19], is a vertex critical graph with chromatic number k+2, its vertices are certain subsets of a set of cardinality m=2n+k. Björner and de Longueville (2003) [5] have shown that its box complex is homotopy equivalent to a sphere, Hom(K2,SGn,k)?Sk. The dihedral group D2m acts canonically on SGn,k, the group C2 with 2 elements acts on K2. We almost determine the (C2×D2m)-homotopy type of Hom(K2,SGn,k) and use this to prove the following results.The graphs SG2s,4 are homotopy test graphs, i.e. for every graph H and r?0 such that Hom(SG2s,4,H) is (r−1)-connected, the chromatic number χ(H) is at least r+6.If k∉{0,1,2,4,8} and n?N(k) then SGn,k is not a homotopy test graph, i.e. there are a graph G and an r?1 such that Hom(SGn,k,G) is (r−1)-connected and χ(G)<r+k+2. 相似文献
949.
The oxidation and reduction of a redox-active aryl-substituted bis(imino)pyridine iron dicarbonyl has been explored to determine whether electron-transfer events are ligand- or metal-based or a combination of both. A series of bis(imino)pyridine iron dicarbonyl compounds, [((iPr)PDI)Fe(CO)(2)](-), ((iPr)PDI)Fe(CO)(2), and [((iPr)PDI)Fe(CO)(2)](+) [(iPr)PDI = 2,6-(2,6-(i)Pr(2)C(6)H(3)N═CMe)(2)C(5)H(3)N], which differ by three oxidation states, were prepared and the electronic structures evaluated using a combination of spectroscopic techniques and, in two cases, [((iPr)PDI)Fe(CO)(2)](+) and [((iPr)PDI)Fe(CO)(2)], metrical parameters from X-ray diffraction. The data establish that the cationic iron dicarbonyl complex is best described as a low-spin iron(I) compound (S(Fe) = ?) with a neutral bis(imino)pyridine chelate. The anionic iron dicarbonyl, [((iPr)PDI)Fe(CO)(2)](-), is also best described as an iron(I) compound but with a two-electron-reduced bis(imino)pyridine. The covalency of the neutral compound, ((iPr)PDI)Fe(CO)(2), suggests that both the oxidative and reductive events are not ligand- or metal-localized but a result of the cooperativity of both entities. 相似文献
950.