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51.
Dao Quang Duy Dang Mo Yoon Jung Woong Ha Choong Hun Lee Bach Thanh Cong 《Applied Surface Science》2009,256(4):1065-1068
We report on the fabrication of carbon nanotubes (CNTs) on Ni-coated stainless steel (SUS) substrates by using dc plasma enhanced chemical vapor deposition. The synthesized CNTs have the diameter of about 30 nm and the length of about 1.2 μm. To verify the effects of SUS substrates on the growth of CNTs, CNTs had also been grown on Ni-coated Si substrates. CNTs grown on the SUS substrates were more uniform compared with those grown on the Si substrates. Field emission properties of the CNT films were measured in the diode configuration, and the turn-on electric field of 3.87 V/μm and field enhancement factor β of about 1737 were obtained from the synthesized CNTs at the gap of 500 μm between the SUS substrate and the anode. These results have not only clarified the effects of the substrate on the growth of CNTs, but also shown the potential of CNTs in field emission applications, especially CNT-based cold-cathode X-ray tubes. 相似文献
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CHEN Ying-Tian ZHANG Yang HU Sen Ho Tso-Hsiu Boon Ham Lim Chen Sin Lim Kok Keong Chong Boon Kok Tan 《理论物理通讯》2009,(10):750-760
In this article, we report the principle and conceptual design of a fundamentally different technology in fabricating high precision aberration free optical devices. The tip-tilt of facet in a mirror array is produced by digitally controlled line-tilts of rows and columns. It has not only provided a cost-effective designing methodology in optical physics but also led to a much finer precision of 1 mili arc sec or less. As examples of the application of the proposed digitalised optics, two case studies have been given: a 10 m Schmidt telescope (off-axis) and an 8 m Cassegrain telescope (on-axis). 相似文献
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Sabyasachi Kar Yu-Shu Wang Zishi Jiang Yang Wang Yew Kam Ho 《Chinese Journal of Physics (Taipei)》2018,56(6):3085-3098
In this article, we review or report recent works on atomic wavelengths in screening environments. We mainly review recent works on the transition, tune-out and magic wavelengths with Coulomb and screened Coulomb potentials. We also present our investigation on tune-out and magic wavelengths for two-electron Yukawa atoms. The various transition wavelengths for two-electron systems with and without screening environments are also presented. 相似文献
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Herein we describe the chelation-assisted C-H and C-C bond activation of carbonyl compounds by Rh1 catalysts. Hydroacylation of olefins was accomplished by utilizing 2-amino-3-picoline as a chelation auxiliary. The same strategy was employed for the C-C bond activation of unstrained ketones. Allylamine 24 was devised as a synthon of formaldehyde. Hydroiminoacylation of alkynes with allylamine 24 was applied to the alkyne cleavage by the aid of cyclohexylamine. 相似文献
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Fermented bean products are used worldwide; most of the products are made using only a few kinds of beans. However, the metabolite changes and contents in the beans generally used during fermentation are unrevealed. Therefore, we selected four different beans (soybean, Glycine max, GM; wild soybean, Glycine soja, GS; common bean, Phaseolus vulgaris, PV; and hyacinth bean, Lablab purpureus, LP) that are the most widely consumed and fermented with Aspergillus oryzae. Then, metabolome and multivariate statistical analysis were performed to figure out metabolite changes during fermentation. In the four beans, carbohydrates were decreased, but amino acids and fatty acids were increased in the four beans as they fermented. The relative amounts of amino acids were relatively abundant in fermented PV and LP as compared to other beans. In contrast, isoflavone aglycones (e.g., daidzein, glycitein, and genistein) and DDMP-conjugated soyasaponins (e.g., soyasaponins βa and γg) were increased in GM and GS during fermentation. Notably, these metabolite changes were more significant in GS than GM. In addition, the increase of antioxidant activity in fermented GS was significant compared to other beans. We expect our research provides a basis to extend choice for bean fermentation for consumers and food producers. 相似文献
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