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排序方式: 共有209条查询结果,搜索用时 15 毫秒
41.
Safaa M. Kishk Enas E. Eltamany Mohamed S. Nafie Roaa M. Khinkar Rawan H. Hareeri Sameh S. Elhady Asmaa S. A. Yassen 《Molecules (Basel, Switzerland)》2022,27(19)
In this study, a series of coumarin derivatives, either alone or as hybrids with cinnamic acid, were synthesized and evaluated for their cytotoxicity against a panel of cancer cells using the MTT assay. Then, the most active compounds were inspected for their mechanism of cytotoxicity by cell-cycle analysis, RT-PCR, DNA fragmentation, and Western blotting techniques. Cytotoxic results showed that compound (4) had a significant cytotoxic effect against HL60 cells (IC50 = 8.09 µM), while compound (8b) had a noticeable activity against HepG2 cells (IC50 = 13.14 µM). Compounds (4) and (8b) mediated their cytotoxicity via PI3K/AKT pathway inhibition. These results were assured by molecular docking studies. These results support further exploratory research focusing on the therapeutic activity of coumarin derivatives as cytotoxic agents. 相似文献
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Colloid Journal - This paper reports an analytical study for the thermophoresis of a circular cylindrical aerosol particle embedded in a porous medium of constant porosity based on the Brinkman... 相似文献
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A. M. Basha E. I. Khalil M. Hussein H. S. Ragab S. El-Konsol 《Zeitschrift für Physik A Hadrons and Nuclei》1991,338(1):3-6
The inner Bremsstrahlung spectrum (I.B.) associated wih the non-unique second forbidden-transition of36Cl was measured using a single channel NaI (Tl) scintillation spectrometer. After making all the necessary corrections, the experimental results were compared with the corresponding theoretical distributions due to the KUB, Lewis and Ford, Nilsson, Ford and Martin and Chang and Falkoff. Also a comparison with those calculated according to Nilsson theory after applying the shape correction factor (M. KUB) was done. The measured spectrum is found to show fairly good agreement with M. KUB theory and its found to deviate therafter from all five theories.The authors would like to thank Prof. Dr. M. El-Nadi and Prof. Dr. O.E. Badawy for their suggestions, interest and encouragement. 相似文献
45.
A newly FDA-approved heart failure therapy (LCZ696, supramolecular complex of sacubitril (SAC) and valsartan (VAL), Entresto?) is analyzed with a stability indicating HPLC–DAD method. For the newly introduced drug, SAC, there is no sufficient information about its stability under various stress conditions. The proposed chromatographic method was applied to the kinetic investigation of the acidic, alkaline, and oxidative degradation of SAC with the estimation of its activation energy and half-life at room temperature by the aid of Arrhenius plots. Kinetic investigation was conducted using either different strengths of HCl, NaOH, and H2O2 at one selected temperature or different temperature degrees at one selected reagent strength, for the acidic, alkaline, and oxidative stress conditions. It was found that the pseudo-first-order kinetics was followed at each case. The half-lives at room temperature using 0.1?M HCl, 0.01?M NaOH, and 15% H2O2 were found to be 20.50, 2.76, and 51.58?hr. The chromatographic method was achieved using Zorbax Eclipse plus-C18 (4.6?×?250?mm, 5?µm) with isocratic elution of mobile phase composed of acetonitrile and 0.025?M phosphate buffer (pH3) in a ratio of 60:40 (v/v). 相似文献
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Copolymer network hydrogels were prepared by gamma irradiation of aqueous solutions of poly(vinyl pyrrolidone) (PVP) and acrylic acid monomer (AAc). The composition of the final hydrogels compared to the composition of the initial preparation solutions of hydrogels was determined. The chemical structure and nature of bonding was characterized by IR spectroscopy analysis, while the thermal durability of the prepared hydrogels was assessed by thermogravimetric analysis (TGA). The kinetic swelling in water and the pH-sensitivity of PVP/AAc copolymer hydrogels was studied. The drug release properties of PVP/AAc hydrogels taking methyl orange indicator as a drug model was investigated. The IR spectra indicate the formation of copolymer networks, whereas the TGA study showed that the PVP/AAc hydrogels possess higher thermal stability than pure PAAc and lower than PVP hydrogels. The kinetic swelling in water showed that all the hydrogels reached equilibrium after 24 h and that the degree of swelling increases with increasing the ratio of AAc in the initial feeding solutions. It was found that the degree of swelling of PVP/AAc hydrogels increases greatly within the pH range 4-7 depending on composition. 相似文献
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Ibrahim Moustafa Sh. Werida Amal H. Etaiw Safaa El-din H. 《Transition Metal Chemistry》2003,28(5):585-591
Various thiophene compounds have been shown to be encapsulated and partly oxidized within the channels of the three-dimensional (3D) host coordination polymers [(R3Sn)3Fe(CN)6]
n
(R = Me, n-Bu or Ph) to give guest–host encapsulated systems. The structure and physical properties of these systems were studied by X-ray powder diffraction, i.r., u.v.–vis., e.p.r. spectra and magnetic measurements. Thiophene compounds do not polymerize within the channels of the host, but rather give paramagnetic charge-transfer guest–host systems. 相似文献
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Antibacterial,DFT and molecular docking studies of Rh(III) complexes of Coumarinyl‐Thiosemicarbazone nuclei based ligands
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Safaa S. Hassan 《应用有机金属化学》2018,32(3)
Coumarinyl thiosemicarbazone derivatives (1E)‐1‐(1‐(2‐oxo‐2H‐chromen‐3‐yl)ethylidene)thiosemicarbazide (OCET), (1E)‐1‐(1‐(6‐bromo‐2‐ oxo‐2H‐chromen‐3‐yl)ethylidene)thiosemicarbazide (BOCET) and 1‐(1‐(3‐oxo‐3H‐benzo[f]chromen‐2‐yl)ethylidene)thiosemicarbazide (NOCET) and their Rh(III) complexes were synthesized, the characterization was carried out by elemental analysis, IR, UV–Visible, mass, magnetic measurement and molar conductance techniques. Data interpretation of the Rh(III) complexes indicates that the ligands of coumarinyl thiosemicarbazone derivatives were formed in stoichiometric ratios as 1:2 (metal: ligand). The studied ligands act as a bidentate ligand by using both azomethine nitrogen and thiol sulphur as monoanion center of donation. The theoretical conformational structure analyses were performed using density functional theory for ligands and complexes at B3LYP functional with 6‐31G(++)d,p basis set for ligands and LANL2DZ basis set for complexes. The charge distribution within the ligands and its Rh(III) complexes was calculated using Mulliken population analysis of (MPA) and natural population analysis (NPA). The antibacterial activity of the prepared compounds was tested against some types of Gram positive and negative bacteria. Molecular docking investigation proved that, the ligands and complexes had interesting interactions with active site amino acids of ribosyltransferase (code: 3GEY). 相似文献
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