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Tren’kin A. A. Almazova K. I. Belonogov A. N. Borovkov V. V. Gorelov E. V. Morozov I. V. Kharitonov S. Yu. 《Technical Physics》2019,64(4):470-474
Technical Physics - Dynamics of the initial stage of discharge in air is studied at atmospheric pressure in a point–plane gap at different parameters of the tip electrode and lengths of the... 相似文献
104.
Timur M. Bulatov Mikhail V. Pugachev Nikita V. Shtyrlin Yurii G. Shtyrlin 《Tetrahedron letters》2018,59(33):3220-3222
A new synthetic approach to 6-alkenyl-substituted pyridoxine derivatives was developed based on the Heck reaction. The reaction, which was catalyzed using a mixture of Pd(OAc)2, (o-Tol)3P and Bu3N as a base, led to seven new 6-alkenyl pyridoxine derivatives. When acrylic acid was used the products of decarboxylation and dimerization were formed. 相似文献
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106.
A Planar‐Chiral Rhodium(III) Catalyst with a Sterically Demanding Cyclopentadienyl Ligand and Its Application in the Enantioselective Synthesis of Dihydroisoquinolones
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Dr. Evgeniya A. Trifonova Nikita M. Ankudinov Dr. Andrey A. Mikhaylov Dr. Denis A. Chusov Dr. Yulia V. Nelyubina Prof. Dr. Dmitry S. Perekalin 《Angewandte Chemie (International ed. in English)》2018,57(26):7714-7718
The rapid development of enantioselective C?H activation reactions has created a demand for new types of catalysts. Herein, we report the synthesis of a novel planar‐chiral rhodium catalyst [(C5H2tBu2CH2tBu)RhI2]2 in two steps from commercially available [(cod)RhCl]2 and tert‐butylacetylene. Pure enantiomers of the catalyst were obtained through separation of its diastereomeric adducts with natural (S)‐proline. The catalyst promoted enantioselective reactions of aryl hydroxamic acids with strained alkenes to give dihydroisoquinolones in high yields (up to 97 %) and with good stereoselectivity (up to 95 % ee). 相似文献
107.
M. Sc. Indrajit Paul M. Sc. Abir Goswami M. Sc. Nikita Mittal Prof. Dr. Michael Schmittel 《Angewandte Chemie (International ed. in English)》2018,57(1):354-358
Three supramolecular slider‐on‐deck systems DS1 – DS3 were obtained as two‐component aggregates from the sliders S1 – S3 and deck D with its three zinc porphyrin (ZnPor) binding sites. The binding of the two‐footed slider to the deck varies with the donor qualities of and the steric hindrance at the pyridine/pyrimidine (pyr) feet, and was effected by two Npyr→ZnPor interactions. Accordingly, the sliders move over the three zinc porphyrins in the deck at different speeds, namely with 32.2, 220, and 440 kHz at room temperature. The addition of N‐methylpyrrolidine as an organocatalyst to DS1 – DS3 generates catalytic three‐component machineries. By using a conjugate addition as a probe reaction, we observed a correlation between the operating speed of the slider‐on‐deck systems and the yields of the catalytic reaction. As the thermodynamic binding of the slider decreases, both the frequency of the sliding motion and the yield of the catalytic reaction increase. 相似文献
108.
Tatiana N. Drebushchak Nikita V. Chukanov Elena V. Boldyreva 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(12):o623-o625
The ɛ‐form of chlorpropamide [systematic name: 4‐chloro‐N‐(propylaminocarbonyl)benzenesulfonamide], C10H13ClN2O3S, has been obtained as single crystals from solution (and not as a polycrystalline sample by heating the α‐, γ‐ or δ‐forms). The results of anisotropic structure refinements for the ɛ‐ and δ‐forms are reported. The density of the δ‐polymorph is the highest, and that of the ɛ‐polymorph the lowest, among the five known chlorpropamide polymorphs. The main intermolecular hydrogen‐bonding pattern in polymorphs δ and ɛ is the same as in polymorphs α, β and γ, but the conformations differ. The densities of the polymorphs were found to depend on the molecular conformations. 相似文献
109.
A. A. Borovkov 《Siberian Mathematical Journal》2008,49(5):796-805
We establish some assertions of Tauberian and Abelian types which enable us to find connections between the asymptotic properties of the Laplace transform at infinity and the asymptotics of the corresponding densities of rapidly decaying distributions (at infinity or in some neighborhood of zero). As applications of our Tauberian type theorems we present asymptotics for the density f (α,ρ)(x) of “extreme” stable laws with parameters (α, ρ) for ρ = ±1 and x lying in the domain of rapid decay of f (α,ρ)(x). This asymptotics had been found in [1–5] by a more complicated method. 相似文献
110.
Dr. Vasily G. Panferov Nikita A. Ivanov Dr. Tony Mazzulli Dr. Davor Brinc Dr. Vathany Kulasingam Prof. Sergey N. Krylov 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202215548
Lateral flow immunoassay (LFIA) is a rapid, simple, and inexpensive point-of-need method. A major limitation of LFIA is a high limit of detection (LOD), which impacts its diagnostic sensitivity. To overcome this limitation, we introduce a signal-enhancement procedure that is performed after completing LFIA and involves controllably moving biotin- and streptavidin-functionalized gold nanoparticles by electrophoresis. The nanoparticles link to immunocomplexes forming multilayer aggregates on the test strip, thus, enhancing the signal. Here, we demonstrate lowering the LOD of hepatitis B surface antigen from approximately 8 to 0.12 ng mL−1, making it clinically acceptable. Testing 118 clinical samples for hepatitis B showed that signal enhancement increased the diagnostic sensitivity of LFIA from 73 % to 98 % while not affecting its 95 % specificity. Electrophoresis-driven enhancement of LFIA is universal (antigen-independent), takes two minutes, and can be performed by an untrained person. 相似文献