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991.
The instability of the plane interface between two oldroydian viscoelastic superposed fluids in the presence of uniform rotation and variable magnetic field in porous medium is considered. For potentially stable configuration, the system is found to be stable for disturbances of all wave numbers. The magnetic field succeeds in stabilizing certain wave-number range, which were unstable in the absence of magnetic field and rotation for the potentially unstable configuration. Sub cases of magnetic free and rotation free configurations are also considered, separately. 相似文献
992.
Matthew Mudge Dr. Boon K. Ng Catherine Jessica Onie Dr. Mohan Bhadbhade Dr. Richard A. Mole Dr. Kirrily C. Rule Dr. Anton P. J. Stampfl Dr. John A. Stride 《Chemphyschem》2014,15(17):3776-3781
The crystal structure of pentamethylbenzene has been obtained for the first time with the use of synchrotron radiation, whilst the low‐energy spectrum of lattice dynamics, dominated by the methyl group torsions, was obtained using inelastic neutron scattering. The effect of symmetry lowering by the removal of a single methyl group relative to hexamethylbenzene has been investigated, including the role that this plays in the charge‐transfer characteristics of complexes formed with tetracyanoethylene. 相似文献
993.
Dr. Katsuhiko Mitachi Dr. Priya Mohan Shajila Siricilla Prof. Michio Kurosu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(16):4554-4558
(2,6‐Dichloro‐4‐methoxyphenyl)(2,4‐dichlorophenyl)methyl trichloroacetimidate ( 3 ) and its polymer‐supported reagent 4 can be successfully applied to a one‐pot protection‐glycosylation reaction to form the disaccharide derivative 7 d for the synthesis of lipid II analogues. The temporary protecting group or linker at the C‐6 position and N‐Troc protecting group of 7 d can be cleaved simultaneously through a reductive condition. Overall yields of syntheses of lipid II ( 1 ) and neryl‐lipid II Nε‐dansylthiourea are significantly improved by using the described methods. 相似文献
994.
Neetha Mohan Cherumuttathu H. Suresh 《International journal of quantum chemistry》2014,114(13):885-894
Interaction energy (Eint) values of a variety of hydrogen, halogen, and dihydrogen bonded complexes in the weak, medium, and strong regimes have been computed using W1BD, MP2, M06L density functional theory, and hybrid methods MP4//MP2, MP4//M06L, and CCSD(T)//MP2. W1BD level Eint and CCSD(T) results reported in the literature show very good agreement (mean absolute deviation = 0.19 kcal/mol). MP2 underestimates Eint while M06L shows accurate behavior for all except halogen and charge‐assisted hydrogen bonds. MP4//MP2, MP4//M06L, and CCSD(T)//MP2 yield Eint very close to those obtained from W1BD. The high accuracy energy data at MP4/MP2 is used to study the effect of a cation (Li+, NH4+) on the Eint. The cation enhances electron donation from the donor to noncovalent bonding region leading to substantial enhancement in Eint (~141–566% for Li+ and ~105–539% for NH4+) and promotes a noncovalent bond in the weak regime to medium regime and that in the medium regime to strong regime. © 2014 Wiley Periodicals, Inc. 相似文献
995.
996.
CdSe Quantum Dots and N719‐Dye Decorated Hierarchical TiO2 Nanorods for the Construction of Efficient Co‐Sensitized Solar Cells
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Three‐dimensional hierarchical TiO2 nanorods (HTNs) decorated with the N719 dye and 3‐mercaptopropionic or oleic acid capped CdSe quantum dots (QDs) in photoanodes for the construction of TiO2 nanorod‐based efficient co‐sensitized solar cells are reported. These HTN co‐sensitized solar cells showed a maximum power‐conversion efficiency of 3.93 %, and a higher open‐circuit voltage and fill factor for the photoanode with 3‐mercaptopropionic acid capped CdSe QDs due to the strong electronic interactions between CdSe QDs, N719 dye and HTNs, and the superior light‐harvesting features of the HTNs. An electrochemical impedance analysis indicated that the superior charge‐collection efficiency and electron diffusion length of the CdSe QD‐coated HTNs improved the photovoltaic performance of these HTN co‐sensitized solar cells. 相似文献
997.
Metabolomics based on liquid chromatography with mass spectrometry reveals the chemical difference in the stems and roots derived from Ephedra sinica
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Mengying Lv Jiaqing Chen Yiqiao Gao Jianbo Sun Qianqian Zhang Mohan Zhang Fengguo Xu Zunjian Zhang 《Journal of separation science》2015,38(19):3331-3336
To better understand different traditional uses of the stems (known as Mahuang) and roots (known as Mahuanggen) of Ephedra sinica, their chemical difference should be investigated. In this study, an ultra‐fast liquid chromatography coupled with ion trap time‐of‐flight mass spectrometry untargeted metabolomics approach was established to reveal global chemical difference between Mahuang and Mahuanggen. Clear separation was observed in scores plots of principal component analysis and orthogonal partial least squares‐discriminant analysis. Twenty two chemical markers responsible for such separation were screened out and unambiguously/tentatively characterized. Then chemical markers of pharmacologically important ephedrine and pseudoephedrine were absolutely quantified using liquid chromatography coupled with tandem mass spectrometry under multiple reaction monitoring mode. The results showed that Mahuang was rich in ephedrine‐type alkaloids, while Mahuanggen was rich in macrocyclic spermine alkaloids. Additionally, different types of flavan‐3‐ols and flavones exist in Mahuang and Mahuanggen extracts. This research facilitates a better understanding of different traditional uses of Mahuang and Mahuanggen and provides references for chemical analysis of other medicinal plants. 相似文献
998.
Prof. Ying‐Wu Lin Dr. Satoshi Nagao Mohan Zhang Dr. Yasuhito Shomura Prof. Yoshiki Higuchi Prof. Shun Hirota 《Angewandte Chemie (International ed. in English)》2015,54(2):511-515
Protein design is a useful method to create novel artificial proteins. A rational approach to design a heterodimeric protein using domain swapping for horse myoglobin (Mb) was developed. As confirmed by X‐ray crystallographic analysis, a heterodimeric Mb with two different active sites was produced efficiently from two surface mutants of Mb, in which the charges of two amino acids involved in the dimer salt bridges were reversed in each mutant individually, with the active site of one mutant modified. This study shows that the method of constructing heterodimeric Mb with domain swapping is useful for designing artificial multiheme proteins. 相似文献
999.
Reactions of the cyanide complexes of the type [(Ind)Ru(PPh3)2CN] (1), [(Ind)Ru(dppe)CN] (2), [(Cp)Ru(PPh3)2CN] (3), with the corresponding chloro complexes [(Ind)Ru(PPh3)2Cl] (4), [(Ind)Ru(dppe)Cl] (5), [(Cp)Ru(PPh3)2Cl] (6), in the presence of NH4PF6 salt give homometallic cyano-bridged compounds of the type [(Ind)(PPh3)2Ru-CN-Ru(PPh3)2(Cp)]PF6 (7), [(Ind)(PPh3)2Ru-CN-Ru(PPh3)2(Ind)] PF6 where Ind = indenyl, η5-C9H7, (8), [(Cp)(PPh3)2Ru-CN-Ru(dppe)(Ind)]PF6, dppe = (Ph2PCH2CH2PPh2) (9), [(Ind(dppe)Ru-CN-Ru(PPh3)2(Ind)PF6 (10) and [(Ind)(dppe)Ru-CN-Ru(PPh3)2(Cp)]PF6 (11) respectively. Reaction of complex3 with [(p-cymene)RuCl2]2 dimer gave a mixed dimeric complex [(Cp)Ru(PPh3)2-CN-RuCl2(p-cymene)] (12). All these complexes have been characterized by IR,1H,13C and31P NMR spectroscopy and C, H, N analyses. 相似文献
1000.
Sanganalmath Praveen U. Sujatha Kunthanahalli M. Bhargavi Somanahalli M. Nayak Vishwanath G. Mohan Bannur M. 《平面色谱法杂志一现代薄层色谱法》2009,22(1):29-33
JPC – Journal of Planar Chromatography – Modern TLC - Theophylline (1, 3-dimethylxanthine) is used both in the prophylaxis of chronic asthma and chronic obstructive airways disease... 相似文献