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991.
使用液相包覆工艺对LiNi_(0.8)Co_(0.15)Al_(0.05)O_2(NCA)材料进行FePO_4包覆改性,利用FePO_4优异的结构稳定性与热稳定性,对NCA的长期可靠性与安全性能进行改良。重点研究FePO_4包覆对NCA材料的改性效果,以及不同包覆量造成的NCA材料电化学性能差异。表面包覆的FePO_4保护层,能够防止NCA材料与电解液直接接触发生副反应,抑制长期循环过程中过渡金属离子的溶出,保持结构的长期稳定性。当包覆量为1.0%(w/w)时,NCA材料表现出最优的综合性能,充放电循环800次后,容量保持率依然高达95%,25℃下存储100 d后,容量保持率也高于95%,达到了兼顾能量密度、使用寿命及安全性能的理想效果。 相似文献
992.
993.
Li Dong-Hui Xu Jie-Feng Guan Hong-Bo 《Journal of Optimization Theory and Applications》2021,190(2):628-649
Journal of Optimization Theory and Applications - We are concerned with the tensor equations whose coefficient tensors are M-tensors. We first propose a Newton method for solving the equation with... 相似文献
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Yue Cui Xia Lin Ting‐Ting Guan Yu Zhang Xing Tang 《Biomedical chromatography : BMC》2010,24(4):406-412
A novel, rapid and selective ultra performance liquid chromatography mass spectrometric method had been developed for the pharmacokinetic study of diclofenac sodium (DS) after single intravenous injection of DS aqueous injection and DS lipid microsphere (LM) injection in rats. Ketoprofen (KP) was used as internal standard. Samples were treated by a one‐step liquid liquid extraction. Separation was performed on an Acquity UPLC? BEH C18 column (50 × 2.1 mm i.d., 1.7 μm). The mobile phase consisted of acetonitrile–0.1% ammonium hydroxide aqueous solution (20 : 80, v/v) initially in the gradient mode. The detection was carried out by means of electrospray ionization mass spectrometry in negative ion mode with multiple‐reaction monitoring mode. Standard curves showed good linearity (r > 0.99) from the plasma concentration of 0.1–50 μg/mL. The lower limit of quantification was 0.1 μg/mL. The intra‐ and inter‐day precisions and the accuracy all satisfied the acceptance criteria. The developed method was validated and successfully applied to the pharmacokinetics study of DS aqueous injection and LM injection. The results showed that the two preparations were bioequivalent in rats. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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997.
Oxovanadium(IV), copper(II) or cobalt(II) acetylacetone complexes immobilized on amino‐functionalized CMK‐3 for the aerobic epoxidation of styrene 下载免费PDF全文
Xiufang Wang Shujie Wu Zhifang Li Xiaoyuan Yang Jing Hu Qisheng Huo Jingqi Guan Qiubin Kan 《应用有机金属化学》2015,29(10):698-706
Oxovanadium(IV), copper(II) and cobalt(II) acetylacetone complexes have been grafted onto amino‐modified CMK‐3‐O (VO‐NH2‐CMK‐3, Cu‐NH2‐CMK‐3 and Co‐NH2‐CMK‐3,respectively) and the materials thus prepared were used as heterogeneous catalysts for the aerobic oxidation of styrene. X‐ray diffraction, nitrogen adsorption–desorption and transmission electron microscopy measurements confirmed the structural integrity of the mesoporous hosts, and spectroscopic characterization techniques (Fourier transform infrared, X‐ray photoelectron, Raman) and thermogravimetry confirmed the ligands and the successful anchoring of the acetylacetone complexes to the modified mesoporous support. VO‐NH2‐CMK‐3 displayed a relatively good catalytic performance with 94.6% of styrene conversion using air as oxidant, while Cu‐NH2‐CMK‐3 gave 99.6% of styrene conversion using tert‐butyl hydroperoxide as oxidant. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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A Highly Selective Two‐Photon Fluorescent Probe for Detection of Cadmium(II) Based on Intramolecular Electron Transfer and its Imaging in Living Cells 下载免费PDF全文
Dr. Zhaohua Shi Qingxin Han Dr. Lizi Yang Huan Yang Dr. Xiaoliang Tang Dr. Wei Dou Zhiqi Li Yange Zhang Yongliang Shao Liping Guan Prof. Dr. Weisheng Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):290-297
A new quinoline‐based probe was designed that shows one‐photon ratiometric and two‐photon off–on changes upon detecting Cd2+. It exhibits fluorescence emission at 407 nm originating from quinoline groups in Tris‐HCl (25 mM , pH 7.40), H2O/EtOH (8:2, v/v). Coordination with Cd2+ causes quenching of the emission at 407 nm and simultaneously yields a remarkable redshift of the emission maximum to 500 nm with an isoemissive point at 439 nm owing to an intramolecular charge‐transfer mechanism. Thus, dual‐emission ratiometric measurement with a large redshift (Δλ=93 nm) and significant changes in the ratio (F500/F439) of the emission intensity (R/R0 up to 27) is established. Moreover, the sensor H2L displays excellent selectivity response, high sensitive fluorescence enhancement, and strong binding ability to Cd2+. Coordination properties of H2L towards Cd2+ were fully investigated by absorption/fluorescence spectroscopy, which indicated the formation of a 2:1 H2L/Cd2+ complex. All complexes were characterized by X‐ray crystallography, and TD‐DFT calculations were performed to understand the origin of optical selectivity shown by H2L. Two‐photon fluorescence microscopy experiments have demonstrated that H2L could be used in live cells for the detection of Cd2+. 相似文献
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1000.