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排序方式: 共有1674条查询结果,搜索用时 31 毫秒
971.
Liliana Maribel Perez-Perez Jos ngel Huerta-Ocampo Saúl Ruiz-Cruz Francisco Javier Cinco-Moroyoqui Francisco Javier Wong-Corral Luisa Alondra Rascn-Valenzuela Miguel Angel Robles-García Ricardo Ivn Gonzlez-Vega Ema Carina Rosas-Burgos María Alba Guadalupe Corella-Madueo Carmen Lizette Del-Toro-Snchez 《Molecules (Basel, Switzerland)》2021,26(9)
The aim of this work was to monitor the quality, antioxidant capacity and digestibility of chickpea exposed to different modified atmospheres. Chickpea quality (proximal analysis, color, texture, and water absorption) and the antioxidant capacity of free, conjugated, and bound phenol fractions obtained from raw and cooked chickpea, were determined. Cooked chickpea was exposed to N2 and CO2 atmospheres for 0, 25, and 50 days, and the antioxidant capacity was analyzed by DPPH (2,2′-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis-[3ethylbenzothiazoline-6-sulfonic acid]), and total phenols. After in vitro digestion, the antioxidant capacity was measured by DPPH, ABTS, FRAP (ferric reducing antioxidant power), and AAPH (2,2′-Azobis [2-methylpropionamidine]). Additionally, quantification of total phenols, and UPLC-MS profile were determined. The results indicated that this grain contain high quality and high protein (18.38%). Bound phenolic compounds showed the highest amount (105.6 mg GAE/100 g) and the highest antioxidant capacity in all techniques. Cooked chickpeas maintained their quality and antioxidant capacity during 50 days of storage at 4 and −20 °C under a nitrogen atmosphere. Free and conjugated phenolic compounds could be hydrolyzed by digestive enzymes, increasing their bioaccessibility and their antioxidant capacity during each step of digestion. The majority compound in all samples was enterodiol, prevailing the flavonoid type in the rest of the identified compounds. Chickpea contains biological interest compounds with antioxidant potential suggesting that this legume can be exploited for various technologies. 相似文献
972.
Luís Urbano D. Tambara Júnior Janaíde C. Rocha Malik Cheriaf Pilar Padilla-Encinas Ana Fernndez-Jimnez Angel Palomo 《Molecules (Basel, Switzerland)》2021,26(7)
This work analyzes the effect of the presence of 5 wt.% of solid sodium salts (Na2SO4, Na2CO3, and Na2SiO3) on calcium sulfoaluminate cement (CSA) hydration, addresses hydration kinetics; 2-, 28-, and 90-d mechanical strength, and reaction product microstructure (with X-ray diffraction (XRD), and Fourier transform infrared spectroscopy, (FTIR). The findings show that the anions affect primarily the reactions involved. Ettringite and AH3, are the majority hydration products, while monosulfates are absent in all of the samples. All three salts hasten CSA hydration and raise the amount of ettringite formed. Na2SO4 induces cracking in the ≥28-d pastes due to post-hardening gypsum and ettringite formation from the excess SO42– present. Anhydrite dissolves more rapidly in the presence of Na2CO3, prompting carbonation. Na2SiO3 raises compressive strength and exhibits strätlingite as one of its reaction products. 相似文献
973.
974.
Samuel Gallego Paula Lorenzo Rosana Alvarez Angel R. de Lera 《Tetrahedron letters》2017,58(3):210-212
Naturally occurring (+)-psychotriasine (+)-1 and congener tetrahydro-β-carboline (+)-3, which are dimeric tryptophan-derived alkaloids with tryptamine and carboline units connected by the indole nitrogen to the quaternary carbon atom of the pyrrolidinoindoline core, have been synthesized for the first time and their absolute configurations confirmed. 相似文献
975.
Dora Balogh Dr. Miguel Angel Aleman Garcia Dr. H. Bauke Albada Prof. Dr. Itamar Willner 《Angewandte Chemie (International ed. in English)》2015,54(40):11652-11656
DNAzyme‐capped mesoporous SiO2 nanoparticles (MP SiO2 NPs) are applied as stimuli‐responsive containers for programmed synthesis. Three types of MP SiO2 NPs are prepared by loading the NPs with Cy3‐DBCO (DBCO=dibenzocyclooctyl), Cy5‐N3, and Cy7‐N3, and capping the NP containers with the Mg2+, Zn2+, and histidine‐dependent DNAzyme sequences, respectively. In the presence of Mg2+ and Zn2+ ions as triggers, the respective DNAzyme‐capped NPs are unlocked, leading to the “click” reaction product Cy3‐Cy5. In turn, in the presence of Mg2+ ions and histidine as triggers the second set of DNAzyme‐capped NPs is unlocked leading to the Cy3‐Cy7 conjugated product. The unloading of the respective NPs and the time‐dependent formation of the products are followed by fluorescence spectroscopy (FRET). A detailed kinetic model for the formation of the different products is formulated and it correlates nicely with the experimental results. 相似文献
976.
Array waveguide evanescent ribbon coupler for card-to-backplane optical interconnects 总被引:1,自引:0,他引:1
A flexible array waveguide evanescent coupler for card-to-backplane optical interconnects is presented. The proposed technique eliminates traditional 90 degrees out-of-plane turns and local waveguide termination of multidrop bus architectures that hinder conventional card-to-backplane optical interconnections. Evanescent coupling between array waveguide ribbons has been successfully demonstrated. Further experiments have been performed to quantify array waveguide coupling length versus transfer efficiency and waveguide misalignment tolerance. Preliminary optical interconnect testing has demonstrated 2.5GHz operation of the coupler ribbons. The successful high-speed coupling confirms the effectiveness of the proposed method for high-speed computing systems. 相似文献
977.
Correlation effects within the GW approximation have been incorporated into the Keldysh nonequilibrium transport formalism. We show that GW describes the Kondo effect and the zero-temperature transport properties of the Anderson model fairly well. Combining the GW scheme with density functional theory and a Wannier function basis set, we illustrate the impact of correlations by computing the I-V characteristics of a hydrogen molecule between two Pt chains. Our results indicate that self-consistency is fundamental for the calculated currents, but that it tends to wash out satellite structures in the spectral function. 相似文献
978.
Pérez-Jiménez AJ Pérez-Jordá JM Sancho-García JC 《The Journal of chemical physics》2007,127(10):104102
We propose a procedure that combines multiconfigurational (MC) wave functions with two-body density correlation functionals by transforming the latter into functionals of the MC natural orbitals and occupation numbers. The method is tested with the spectroscopic constants of a set of 11 diatomics, the diradical-involved automerization barrier of cyclobutadiene, the energy difference between triplet and open-shell singlet states in He and the methylene molecule, and the magnetic coupling constants of several systems, such as NiO, KNiF(3), K(2)NiF(4), La(2)CuO(4), alpha-4-dehydrotoluene, 1,1('),5,5(')-tetramethyl-6,6(')-dioxo-3,3(')-biverdazyl, [Cu(2)Cl(6)](-2), copper(II) acetate monohidrate and H-He-H. The procedure is applied to the Colle-Salvetti [Theor. Chim. Acta 37, 329 (1975); 53, 55 (1979)], functional and to a size-consistent functional depending on the on-top pair density (F1-5-N(eff)). On average, the best results are provided by the transformed F1-5-N(eff) [J. Chem. Phys. 114, 2022 (2001)] functional. 相似文献
979.
The authors propose a new approach to understand the electrostatic surface contributions to the interactions of large but finite periodic distributions of charges. They present a simple method to derive and interpret the surface contribution to any electrostatic field produced by a periodic distribution of charges. They discuss the physical and mathematical interpretations of this term. They present several examples and physical details associated with the calculation of the surface term. Finally, they provide a simple derivation of the surface contribution to the virial. This term does not disappear even if tinfoil boundary conditions are applied. 相似文献
980.
The sulfoxide-induced preference for a migrating trajectory in the vinylallene [1,5]-H sigmatropic shift (resulting in stereodefined trienes in the conceptual equivalent of torquoselectivity in electrocyclizations), originally reported by Okamura, has been computationally studied at the B3LYP/6-311++G(3df,2p)//B3LYP/6-31++G(d,p) level. The face selectivity this group induces in the [1,5]-H shift is enhanced by bulky geminal substituents and is not reproduced by any of the other (more than 20) substituents tested. Analysis of transition-state geometries or charges and evaluation of steric effects did not show any correlation with the preferences. The origin of this selectivity is thought to lie in a secondary orbital interaction (SOI) involving the termini of the pericyclic array and the sulfinyl group which is only observed for this substituent. This secondary orbital interaction, arising from the favorable energies of the orbitals involved, is enhanced in the transition structure due to a better orbital overlap (piC2-C3-->sigma*C1-S), which correlates with a piC2-C3-->sigma*C6-H SOI, which is more important in the transition structure, that weakens the C-H bond, thus lowering the energy of the corresponding transition structure. 相似文献