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991.
MgAl2SiO6-incorporated poly(ethylene oxide)-based electrolytes for all-solid-state lithium batteries
Poly(ethylene oxide) (PEO)-based composite polymer electrolytes (CPEs), comprising various concentrations of lithium hexafluorophosphate and magnesium aluminium silicate, were prepared by hot-press technique. The membranes were characterised by scanning electron microscopy, tensile and thermal analyses. It has been demonstrated that the incorporation of the ceramic filler in the polymeric matrix has significantly enhanced the ionic conductivity, thermal stability and mechanical integrity of the membrane. It also improved the interfacial properties with lithium electrode. Finally, an all-solid-state lithium cell composed of Li/CPE/LiFePO4 has been assembled and its cycling performance was analysed at 70 °C. The cell delivered a discharge capacity of 115 mAh g?1 at 1 °C rate and is found to be higher than previous reports. 相似文献
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Tailoring RuII Pyridine/Triazole Oxygenation Catalysts and Using Photoreactivity to Probe their Electronic Properties 下载免费PDF全文
Fritz Weisser Hendrik Stevens Johannes Klein Margarethe van der Meer Dr. Stephan Hohloch Prof. Dr. Biprajit Sarkar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8926-8938
Tuning of ligand properties is at the heart of influencing chemical reactivity and generating tailor‐made catalysts. Herein, three series of complexes [Ru(L)(Cl)(X)]PF6 (X=DMSO, PPh3, or CD3CN) with tripodal ligands (L1–L5) containing pyridine and triazole arms are presented. Triazole‐for‐pyridine substitution and the substituent at the triazole systematically influence the redox behavior and photoreactivity of the complexes. The mechanism of the light‐driven ligand exchange of the DMSO complexes in CD3CN could be elucidated, and two seven‐coordinate intermediates were identified. Finally, tuning of the ligand framework was applied to the catalytic oxygenation of alkanes, for which the DMSO complexes were the best catalysts and the yield improved with increasing number of triazole arms. These results thus show how click‐derived ligands can be tuned on demand for catalytic processes. 相似文献
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Prof. Dr. K. C. Nicolaou Dr. Kiran Kumar Pulukuri Ruocheng Yu Dr. Stephan Rigol Dr. Philipp Heretsch Dr. Charles I. Grove Christopher R. H. Hale Dr. Abdelatif ElMarrouni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8559-8570
The total synthesis of Δ12‐prostaglandin J3 (Δ12‐PGJ3, 1 ), a reported leukemia stem cell ablator, through a number of strategies and tactics is described. The signature cross‐conjugated dienone structural motif of 1 was forged by an aldol reaction/dehydration sequence from key building blocks enone 13 and aldehyde 14 , whose lone stereocenters were generated by an asymmetric Tsuji–Trost reaction and an asymmetric Mukaiyama aldol reaction, respectively. During this program, a substituent‐governed regioselectivity pattern for the Rh‐catalyzed C?H functionalization of cyclopentenes and related olefins was discovered. The evolution of the synthesis of 1 from the original strategy to the final streamlined process proceeded through improvements in the construction of both fragments 13 and 14 , exploration of the chemistry of the hitherto underutilized chiral lactone synthon 57 , and a diastereoselective alkylation of a cyclopentenone intermediate. The described chemistry sets the stage for large‐scale production of Δ12‐PGJ3 and designed analogues for further biological and pharmacological studies. 相似文献
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Sylvestre P. J. T. Bachollet Dr. Daniel Volz Béla Fiser Stephan Münch Dr. Franziska Rönicke Dr. Jokin Carrillo Harry Adams Prof. Ute Schepers Enrique Gómez‐Bengoa Prof. Stefan Bräse Prof. Joseph P. A. Harrity 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12430-12438
Ten borylated bipyridines (BOBIPYs) have been synthesized and selected structural modifications have been made that allow useful structure–optical property relationships to be gathered. These systems have been further investigated using DFT calculations and spectroscopic measurements, showing blue to green fluorescence with quantum yields up to 41 %. They allow full mapping of the structure to determine where selected functionalities can be implemented, to tune the optical properties or to incorporate linking groups. The best derivative was thus functionalised with an alkyne linker, which would enable further applications through click chemistry and in this optic, the stability of the fluorophores has been evaluated. 相似文献
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The VPE growth of GaAs in the system GaAs AsCl3 with either H2 or He as the Carrier gas was studied in the range of low deposition temperatures. Down to about 670 °C the growth in the H2-system is limited by the kinetics of chlorine desorption by molecular hydrogen. The increase in growth rate at lower temperatures results from the onset of GaCl3-desorption (disproportionation mechanism). The addition of NH3 to the vapour phase enhances this effect. Below about 700 °C the growth rate in the GaAs AsCl3 H2 NH3 system becomes comparable to that in the GaAs AsCl3 He-system, where the GaCl3 desorption mechanism is the only possible growth mechanism. 相似文献