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41.
Tang Guangxian Shafee Ahmad Nam Nguyen Dang Tlili Iskander 《Journal of Thermal Analysis and Calorimetry》2021,143(6):4249-4260
Journal of Thermal Analysis and Calorimetry - Electrical sensor has been considered in the current attempt. Combination of buoyancy, electric and radiative forces has been included in the governing... 相似文献
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Nadya Abbood Dr. Tien Duy Vo Dr. Jonas Watzel Dr. Kenan A. J. Bozhueyuek Prof. Dr. Helge B. Bode 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202103963
Bacterial natural products in general, and non-ribosomally synthesized peptides in particular, are structurally diverse and provide us with a broad range of pharmaceutically relevant bioactivities. Yet, traditional natural product research suffers from rediscovering the same scaffolds and has been stigmatized as inefficient, time-, labour- and cost-intensive. Combinatorial chemistry, on the other hand, can produce new molecules in greater numbers, cheaper and in less time than traditional natural product discovery, but also fails to meet current medical needs due to the limited biologically relevant chemical space that can be addressed. Consequently, methods for the high throughput generation of new natural products would offer a new approach to identifying novel bioactive chemical entities for the hit to lead phase of drug discovery programs. As a follow-up to our previously published proof-of-principle study on generating bipartite type S non-ribosomal peptide synthetases (NRPSs), we now envisaged the de novo generation of non-ribosomal peptides (NRPs) on an unreached scale. Using synthetic zippers, we split NRPSs in up to three subunits and rapidly generated different bi- and tripartite NRPS libraries to produce 49 peptides, peptide derivatives, and de novo peptides at good titres up to 145 mg L−1. A further advantage of type S NRPSs not only is the possibility to easily expand the created libraries by re-using previously created type S NRPS, but that functions of individual domains as well as domain-domain interactions can be studied and assigned rapidly. 相似文献
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Dirhodium(II) Carboxylate Catalyzed Formation of 1,2,3‐Trisubstituted Indoles from Styryl Azides 下载免费PDF全文
Crystalann Jones Quyen Nguyen Prof. Dr. Tom G. Driver 《Angewandte Chemie (International ed. in English)》2014,53(3):785-788
Dirhodium(II)‐carboxylate complexes were discovered to promote the selective migration of acyl groups in trisubstituted styryl azides to form 1,2,3‐trisubstituted indoles. The styryl azides are readily available in three steps from cyclobutanone and 2‐iodoaniline. 相似文献
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One‐Step Pyro‐Synthesis of a Nanostructured Mn3O4/C Electrode with Long Cycle Stability for Rechargeable Lithium‐Ion Batteries 下载免费PDF全文
Muhammad Hilmy Alfaruqi Dr. Jihyeon Gim Sungjin Kim Jinju Song Pham Tung Duong Jeonggeun Jo Dr. Joseph Paul Baboo Dr. Zhiliang Xiu Dr. Vinod Mathew Prof. Jaekook Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2039-2045
A nanostructured Mn3O4/C electrode was prepared by a one‐step polyol‐assisted pyro‐synthesis without any post‐heat treatments. The as‐prepared Mn3O4/C revealed nanostructured morphology comprised of secondary aggregates formed from carbon‐coated primary particles of average diameters ranging between 20 and 40 nm, as evidenced from the electron microscopy studies. The N2 adsorption studies reveal a hierarchical porous feature in the nanostructured electrode. The nanostructured morphology appears to be related to the present rapid combustion strategy. The nanostructured porous Mn3O4/C electrode demonstrated impressive electrode properties with reversible capacities of 666 mAh g?1 at a current density of 33 mA g?1, good capacity retentions (1141 mAh g?1 with 100 % Coulombic efficiencies at the 100th cycle), and rate capabilities (307 and 202 mAh g?1 at 528 and 1056 mA g?1, respectively) when tested as an anode for lithium‐ion battery applications. 相似文献
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Density functional calculations are performed to study the energetic, structural, and electronic properties of graphene and silicene functionalized with hydrogen. Our calculations predict that H atoms bind much more strongly to silicene than to graphene. The adsorbed H atoms tend to cooperatively stabilize each other leading to a two‐dimensional nucleation and growth mechanism. The different structural and electronic modifications induced by H in fully functionalized graphene and silicene (known as graphane and silicane) are also explained. Finally, the electronic properties of defective graphane with multiple hydrogen vacancies are investigated. Engineering the vacancies in graphane offers a way to modify the electronic properties of this material. 相似文献
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Acetyl Methyl Torsion in N‐Ethylacetamide: A Challenge for Microwave Spectroscopy and Quantum Chemistry 下载免费PDF全文
Raphaela Kannengießer Marcel J. Lach Prof. Dr. Wolfgang Stahl Dr. Ha Vinh Lam Nguyen 《Chemphyschem》2015,16(9):1906-1911
The gas‐phase structures and parameters describing acetyl methyl torsion of N‐ethylacetamide are determined with high accuracy, using a combination of molecular beam Fourier‐transform microwave spectroscopy and quantum chemical calculations. Conformational studies at the MP2 level of theory yield four minima on the energy surface. The most energetically favorable conformer, which possesses C1 symmetry, is assigned. Due to the torsional barrier of 73.4782(1) cm?1 of the acetyl methyl group, fine splitting up to 4.9 GHz is found in the spectrum. The conformational structure is not only confirmed by the rotational constants, but also by the orientation of the internal rotor. The 14N quadrupole hyperfine splittings are analyzed and the deduced coupling constants are compared with the calculated values. 相似文献
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