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排序方式: 共有174条查询结果,搜索用时 15 毫秒
121.
Khalid Mohammed Khan Aneela Karim Sumayya Saied Nida Ambreen Xayale Rustamova Shagufta Naureen Sajid Mansoor Muhammad Ali Shahnaz Perveen M. Iqbal Choudhary Guillermo Antonio Morales 《Molecular diversity》2014,18(2):295-306
Twenty eight (28) derivatives 2–29 were synthesized and four analogs were found to exhibit single-digit $\hbox {IC}_{50}$ values as $\upbeta $ -glucuronidase inhibitors. Molecular modeling indicates that three factors: substituent R, lone pair on the nitrogen of azomethine part, and the interactions made by the main skeleton of the molecule, determined the enzyme inhibitory potential of these compounds. The planar conformation of the molecules allows them to fit deep inside the pocket while blocking the entry of other physiological substrates seems to play an important role in their activity. 相似文献
122.
Mansoor H. Alshehri Barry J. Cox James M. Hill 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(9):1-11
Fullerenes have attracted considerable attention in various areas of science and technology. Owing to their exceptional physical, chemical, and biological properties, they have many applications, particularly in cosmetic and medical products. Using the Lennard-Jones 6-12 potential function and the continuum approximation, which assumes that intermolecular interactions can be approximated by average atomic surface densities, we determine the binding energies of a C60 fullerene with respect to both single-strand and double-strand DNA molecules. We assume that all configurations are in a vacuum and that the C60 fullerene is initially at rest. Double integrals are performed to determine the interaction energy of the system. We find that the C60 fullerene binds to the double-strand DNA molecule, at either the major or minor grooves, with binding energies of ?4.7 eV or ?2.3 eV, respectively, and that the C60 molecule binds to the single-strand DNA molecule with a binding energy of ?1.6 eV. Our results suggest that the C60 molecule is most likely to be linked to the major groove of the dsDNA molecule. 相似文献
123.
A simple and fast stripping voltammetric detection method has been designed for selective and non-selective measurements of heavy metal ions in a flow-injection system. A special computer numerical method is introduced for calculating the analyte signal and noise reduction, where the signal is calculated based on the partial and total charge exchange at electrode surface. For a selective determination, the currents are integrated in the range of the oxidation and reduction of the analyte. For non-selective measurements, the integration range is set for the whole potential scan range (including oxidation and reduction of the Au surface). The time for stripping has been shown to be less than 300 ms. The main advantages of the detection method are as follows: first, removal of oxygen from the measured solution is not required; second, it is sufficiently fast for the determination of heavy metal ions in various chromatographic analysis methods. The limit of detection for tested ions was between 3 x 10(-9) and 6 x 10(-10) M, and the relative standard deviation at 50 ppb Pb2+ was 4.7% for 10 runs. 相似文献
124.
Ab initio molecular orbital theory has been used to calculate enthalpies of formation of the keto tautomers of 1-hydroxyisoquinoline, 5-hydroxyisoquinoline, and 1,5-dihydroxyisoquinoline. The high-level composite method G3//B3LYP has been used for this study, and the results have been compared with available experimental values. The keto tautomer is more favourable for 1-hydroxyisoquinoline and 1,5-dihydroxyisoquinoline, and the experimental enthalpies of formation are in better agreement with the theoretical enthalpies of formation of the keto forms. 相似文献
125.
Ab initio molecular orbital theory has been used to calculate enthalpies of formation of isoquinoline, 1-hydroxyisoquinoline, 5-hydroxyisoquinoline, and 1,5-dihydroxyisoquinoline as well as some pyridine and quinoline derivatives. The proton affinities of the four isoquinoline derivatives were also obtained. The high-level composite methods G3(MP2), G3(MP2)//B3LYP, G3//B3LYP, and CBS-QB3 have been used for this study, and the results have been compared with available experimental values. For six of the eight studied compounds, the theoretical enthalpies of formation were very close to the experimental values (to within 4.3 kJ · mol−1); where comparison was possible, the theoretical and experimental proton affinities were also in excellent agreement with one another. However, there is an extraordinary discrepancy between theory and experiment for the enthalpies of formation of 1-hydroxyisoquinoline and 1,5-dihydroxyisoquinoline, suggesting that the experimental values for these two compounds should perhaps be re-examined. We also show that popular low cost computational methods such as B3LYP and MP2 show very large deviations from the benchmark values. 相似文献
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129.
Zhonghui Xu Weishuai Lv Mansoor B.A. Jalil Jinsong Huang Yangwan Zhong Yuguang Chen 《Physics letters. A》2018,382(39):2868-2875
Spin transport properties in a non-uniform quantum wire (QW) in the presence of both the Rashba and Dresselhaus spin–orbit couplings (SOCs) is investigated by using the non-equilibrium Green's function (NEGF) method combined with the Landauer Büttiker formalism. It is found that such a non-uniform quantum wire exhibits considerable spin polarization in its conductance in the influence of both the Rashba and Dresselhaus SOCs, and that the two SOCs' strengths strongly affect both the magnitude and sign of the electron spin polarization. Interestingly, the Rashba and Dresselhaus SOCs play the same modulating role in the electron spin polarization. The proposed nanostructure can potentially be utilized to devise an all-electrical spintronic device. 相似文献
130.
Farbod Mansoor Shojaeenezhad Seyyedeh Saadat 《Journal of Solid State Electrochemistry》2019,23(11):3009-3017
Journal of Solid State Electrochemistry - In this work, pure graphene hydrogel (GH) and graphene/Ag nanoparticle (GH-AgNP) composite hydrogels with various wt% of 0.01, 0.1, 1, 10, 30, and 50% Ag... 相似文献