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Wang Feng Liu Jie Zhong Lipeng Hai Bin Zhou Yongyan Tang Nian Li Li 《Plasma Chemistry and Plasma Processing》2021,41(1):133-153
Plasma Chemistry and Plasma Processing - C6F12O (1,1,1,2,2,4,5,5,5-nonafluoro-4-(trifluoromethyl)pentan-3-one) is one of the most potential alternative insulation medium to SF6 due to its excellent... 相似文献
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155.
Yifan Zhang Dr. Yamin Zhang Yi Cao Minghao Xie Dr. Jiabao Li Alex Balzer Prof. Nian Liu Prof. Z. John Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(50):12900-12909
Spinel ferrites are promising anode materials for lithium-ion batteries (LIBs) owing to their high theoretical specific capacities. However, their practical application is impeded by inherent low conductivity and severe volume expansion, which can be surpassed by increasing the surface-to-volume ratio of nanoparticles. Currently, most methods produce spinel ferrite nanoparticles with large size and severe aggregation, degrading their electrochemical performance. In this study, a low-temperature aminolytic route was designed to synthesize sub-10 nm CoFe2O4 nanoparticles with good dispersion through carefully exploiting the reaction of acetates and oleylamine. The performance of CoFe2O4 nanoparticles obtained by a traditional co-precipitation method was also investigated for comparison. This work demonstrates that CoFe2O4 nanoparticles synthesized by the aminolytic route are promising as anode materials for LIBs. Besides, this method can be extended to design other spinel ferrites for energy storage devices with superior performance by simply changing the starting material, such as MnFe2O4, MgFe2O4, ZnFe2O4, and so on. 相似文献
156.
The Ramanujan Journal - Let $$F(x) \in \mathbb {Z}[x_1 , x_2 ,\ldots , x_n ]$$ , $$n\ge 3$$ , be an n-variable quadratic polynomial with a nonsingular quadratic part. Using the circle method we... 相似文献
157.
A simple and effective method for the detection of electrochemically inactive sodium dodecyl sulfate (SDS) has been designed, based on different binding affinity of polyethyleneimine (PEI) toward electrochemically active eosin Y and electrochemically inactive SDS. The stronger binding affinity of the PEI toward SDS than eosin Y results in the decrease of the redox peak current of surface confined eosin Y and provides a quantitative readout for the SDS. The difference in value of the cathodic peak current showed a linear relationship with SDS concentration in a concentration range from 1 to 40 μg mL−1, and a detection limit of 0.9 μg mL−1 for SDS was obtained. Furthermore, the method has been successfully applied to the detection of SDS in real samples. The developed approach provided a simple and reliable detection for SDS and might have potential applications in electrochemical methods for inactive molecules. 相似文献
158.
Jin Can Chen Lan Mei Chen Si Yan Liao Kang Cheng Zheng Liang Nian Ji 《International journal of quantum chemistry》2010,110(6):1252-1263
The hydrolysis process of Ru (III) complex [Htrz][trans‐RuCl4(1‐H‐1,2,4‐triazole)(dmso‐S)] 1 , a potential antitumor complex similar to the well‐known anticancer agent [ImH][trans‐RuCl4(Im)(dmso‐S)] (NAMI‐A), has been investigated by using density functional theory (DFT) method, and the solvent effect was also considered and calculated by conductor‐like polarizable calculation model (CPCM). Meanwhile, the hydrolysis process of the NH‐tautomeric isomer, [Htrz][trans‐RuCl4(4‐H‐1,2,4‐triazole)(dmso‐S)] 2 , was also modeled and predicted by the same methods. The structural characteristics and the detailed energy profiles for the hydrolysis processes of two isomers have been obtained. The analysis of thermodynamic and kinetic characteristics of hydrolysis reaction suggests the following: for the first hydrolysis step, the Complex 1 has lower hydrolysis rate than the reported anticancer drug NAMI‐A, and the result is in accordance with experimental one. However, Complex 1 has obviously higher hydrolysis rate than its isomer Complex 2 , and the result was reasonably explained in theory. For the second hydrolysis step, the formation of cis‐diaqua species is thermodynamic preferred to that of trans isomers. In addition, the trend in nucleophilic attack abilities (A) of hydrolysis products by pertinent biomolecules was revealed and predicted. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
159.
Pei Yuan Lingzhi Zhao Nian Liu Guangfeng Wei Yunhua Wang Prof. Graeme J. Auchterlonie J. Drennan Prof. Gao Qing Lu Prof. Jin Zou Prof. Chengzhong Yu Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1629-1637
An intriguing evolution from a simple internal helix to a hierarchical helical (HH) mesostructure with both internal and external helices or a complicated screwlike and concentric circular (CC) mesostructure is successfully observed. The complicated helical structures are determined by TEM studies and 3D electron tomography. We demonstrate a topological helix–coil transition between the internal and external helices to reveal the origin of the HH mesostructure and the relationship between the straight helical and HH rods. Moreover, the boundary condition of the helix–coil transition is clarified to explain in detail the formation of complex helical structures, such as the screwlike mesostructure. It is proposed that the final structural characteristics are determined exactly by the balance between the decrease in the surface free energy and the maintenance of the hexagonal packing in one individual rod, which explains the formation of unusual CC, HH, and screwlike morphologies in one pot. Our success has opened new opportunities in the characterization of complex porous architectures, thus paving a way to remarkable advances in the fields of synthesis, understanding, and application of novel porous materials. 相似文献
160.
Pei Nian Liu Dr. Fu Hai Su Dr. Ting Bin Wen Dr. Herman H.‐Y. Sung Dr. Ian D. Williams Prof. Dr. Guochen Jia Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(26):7889-7897
The new ruthenium complex [Ru(N3P)(OAc)][BPh4] ( 4 ), in which N3P is the N,P mixed tetradentate ligand N,N‐bis[(pyridin‐2‐yl)methyl]‐[2‐(diphenylphosphino)phenyl]methanamine was synthesized. The complex was found to be catalytically active for the endo cycloisomerization of alkynols. The catalytic reactions can be used to synthesize five‐, six‐, and seven‐membered endo‐cyclic enol ethers in good to excellent yields. A catalytic cycle involving a vinylidene intermediate was proposed for the catalytic reactions. Treatment of complex 4 with PhC?CH and H2O gave the alkyl complex [Ru(CH2Ph)(CO)(N3P)][BPh4] ( 30 ), which supports the assumption that the catalytic reactions involve addition of a hydroxyl group to the C?C bond of vinylidene ligands. 相似文献