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Designs, Codes and Cryptography - The paper introduces a method for constructing 2-resolvable t-designs for $$t=3,4$$ . The main idea is based on the assumption that there exists a partition of a... 相似文献
234.
In this paper, a computational study using the moving element method (MEM) is carried out to investigate the dynamic response of a high-speed rail (HSR) traveling at non-uniform speeds. A new and exact formulation for calculating the generalized mass, damping and stiffness matrices of the moving element is proposed. Two wheel–rail contact models are examined. One is linear and the other nonlinear. A parametric study is carried out to understand the effects of various factors on the dynamic amplification factor (DAF) in contact force between the wheel and rail such as the amplitude of acceleration/deceleration of the train, the severity of railhead roughness and the wheel load. Resonance in the vibration response can possibly occur at various stages of the journey of the HSR when the speed of the train matches the resonance speed. As to be expected, the DAF in contact force peaks when resonance occurs. The effects of the severity of railhead roughness and the wheel load on the occurrence of the jumping wheel phenomenon, which occurs when there is a momentary loss of contact between the wheel and track, are investigated. 相似文献
235.
N. V. Tukumova T. R. Usacheva Tran Thi Dieu Thuan V. A. Sharnin 《Russian Journal of Inorganic Chemistry》2014,59(2):148-151
Composition and stability of coordination compounds of nickel(II) and cobalt(II) ions with maleic acid anion in aqueous isopropanol solutions (H2O-IPA) of composition χIPA = 0–0.5 mole fraction was studied by potentiometric titration at ionic strength of 0.1 maintained with sodium perchlorate at 298.15 K. Monoligand complexes of Ni2+ and Co2+ ions with maleic acid anion become stronger when isopropanol content rises. In the solvent of the studied composition, Co2+ ions form less stable complexes than Ni2+ ions that corresponds to the Irving-Williams series established for aqueous solutions. Variations in complex stability are more expressed at small IPA content and differ within experimental error at χIPA = 0.5 mole fraction. Obtained results were compared with literature data for akin compounds. 相似文献
236.
Electrodeposited Amorphous Tungsten‐doped Cobalt Oxide as an Efficient Catalyst for the Oxygen Evolution Reaction 下载免费PDF全文
Linh N. Nguyen Dr. Ung Thi Dieu Thuy Dr. Quang Duc Truong Prof. Itaru Honma Prof. Quang Liem Nguyen Dr. Phong D. Tran 《化学:亚洲杂志》2018,13(12):1530-1534
Thin film of amorphous tungsten‐doped cobalt oxide (W:CoO) was successfully grown on a conducting electrode via an electrochemical oxidation process employing a [Co(WS4)2]2? deposition bath. The W:CoO catalyst displays an attractive performance for the oxygen evolution reaction in an alkaline solution. In an NaOH solution of pH 13, W:CoO operates with a moderate onset overpotential of 230 mV and requires 320 mV overpotential to generate a catalytic current density of 10 mA cm?2. A low Tafel slope of 45 mV decade?1 was determined, indicating a rapid O2‐evolving kinetics. The as‐prepared W:CoO belongs to the best cobalt oxide‐based catalysts ever reported for the oxygen evolution (OER) reaction. 相似文献
237.
Dr. Tatsuki Kurokawa Dr. Shigeki Kiyonaka Dr. Eiji Nakata Dr. Masayuki Endo Shohei Koyama Emiko Mori Nam Ha Tran Huyen Dinh Dr. Yuki Suzuki Kumi Hidaka Dr. Masaaki Kawata Dr. Chikara Sato Prof. Hiroshi Sugiyama Prof. Takashi Morii Prof. Yasuo Mori 《Angewandte Chemie (International ed. in English)》2018,57(10):2586-2591
In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K+ channel proteins are assembled through zinc‐finger protein (ZFP)‐adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP‐fused Kir3 channels and ZFP‐based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K+ channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells. 相似文献
238.
Yhiya Amen Qinchang Zhu Hai-Bang Tran Mohamed S. Afifi Ahmed F. Halim Ahmed Ashour 《Natural product research》2018,32(16):1955-1959
Rho-kinase enzymes are one of the most important targets recently identified in our bodies. Several lines of evidence indicate that these enzymes are involved in many diseases and cellular disorders. ROCK inhibitors may have clinical applications for cancer, hypertension, glaucoma, etc. Our study aims to identify the possible involvement of Rho-kinase inhibition to the multiple biological activities of adlay seeds and provide a rationale for their folkloric medicines. Hence, we evaluated Rho-kinase I and II inhibitory activity of the ethanol extract and 28 compounds derived from the seeds. A molecular docking assay was designed to estimate the binding affinity of the tested compounds with the target enzymes. The results of our study suggest a possible involvement of Rho-kinase inhibition to the multiple biological activities of the seeds. Furthermore, the results obtained with the tested compounds revealed some interesting skeletons as a scaffold for design and development of natural Rho-kinase inhibitors. 相似文献
239.
Bagrat A. Shainyan Elena N. Suslova Tran Dinh Phien Sergey A. Shlykov Erich Kleinpeter 《Tetrahedron》2018,74(32):4299-4307
1-(Dimethylamino)-1-phenyl-1-silacyclohexane 1, was synthesized, and its molecular structure and conformational properties studied by gas-phase electron diffraction (GED), low temperature 13C NMR spectroscopy and quantum-chemical calculations. The predominance of the 1-Phax conformer (1-Pheq:1-Phax ratio of 20:80%, ΔG°(317?K)?=??0.87?kcal/mol) in the gas phase is close to the theoretically estimated conformational equilibrium. In solution, low temperature NMR spectroscopy showed analyzable decoalescence of Cipso and C(1,5) carbon signals in 13C NMR spectra at 103?K. Opposite to the gas state in the freon solution employed (CD2Cl2/CHFCl2/CHFCl2?=?1:1:3), which is still liquid at 100?K, the 1-Pheq conformer was found to be the preferred one [(1-Pheq: 1-Phax?=?77%: 23%, K?=?77/23?=?2.8; ?ΔG°?=??RT ln K (at 103?K)?=?0.44?±?0.1?kcal/mol]. When comparing 1 with 1-phenyl-1-(X)silacylohexanes (X?=?H, Me, OMe, F, Cl), studied so far, the trend of predominance of the Phax conformer in the gas phase and of the Pheq conformer in solution is confirmed. 相似文献
240.
Huynh Le Thanh Nguyen Tran Thi Thuy Dung Nguyen Hoang Hai Au Nguyen Thi Thu Trang Tran Van Man Grag Akhil Le My Loan Phung 《Journal of Solid State Electrochemistry》2018,22(7):2247-2254
Journal of Solid State Electrochemistry - Olivine LiFePO4 (LFP) is a promising cathode material for high-rated lithium-ion batteries. However, olivine faced a severe disadvantage of low... 相似文献