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101.
Transient stress and interfacial area generated during breakup of a Newtonian thread immersed in a Newtonian medium 总被引:1,自引:0,他引:1
Abdelhamid?Zkiek Wei?Yu Mosto?BousminaEmail author Miroslav?Grmela 《Rheologica Acta》2004,43(4):333-341
The transient stress and the transient average orientation generated by the breakup process of a long Newtonian filament imbedded in a quiescent Newtonian viscous liquid have been calculated. Rayleigh disturbances were used to describe the relaxation of the filament and the variation of interfacial area in the absence of flow during the course of disintegration process. The effect of viscosity ratio and initial radius of the filament were discussed. It was demonstrated that the predictions of the model in terms of the time-evolution of interfacial area can be used to select the best conditions for carrying out the breaking thread experiments. The predictions of the proposed model were compared to some experimental data on polyamide/polyethylene system. 相似文献
102.
The geometrical structures, relative stabilities, electronic and magnetic properties of small PdnIr (n = 1–8) clusters have been systematically investigated using density functional theory at the B3PW91 level. The optimised geometries show that the lowest-energy structures of PdnIr clusters prefer a three-dimensional configuration. The relative stability of these clusters was examined by analysis of the binding energies per atom, fragmentation energies, the second-order difference of energies and the HOMO–LUMO energy gaps as a function of cluster size. The obtained results exhibit that the Pd2Ir, Pd3Ir and Pd5Ir clusters are more stable than their neighbouring clusters. The energy gap of the Pd2Ir cluster is the largest of all the clusters (2.258 eV). In addition, the charge transfers, vertical ionisation potentials, vertical electron affinities and chemical hardness were calculated and discussed. The magnetism calculations indicate that the total magnetic moment of PdnIr clusters is mainly localised on the iridium atom for Pd1–6Ir clusters. Meanwhile, the 5d orbital plays the key role in the magnetic moment of the iridium atom. 相似文献
103.
Abdou O. Abdelhamid Mamdouh A. M. Afifi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2703-2713
2-[1,2-Diaza-3-(2,3-dimethyl-5-oxo-1-phenyl(3-pyrazolin-4-yl))prop-2-enylidene]-3-phenyl-5-substituted 1,3,4-thiadiazolines and 2-{[4-(2,3-dimethyl-5-oxo-1-phenyl(3-pyrazolin-4-yl))(1,3-thiazol-2-yl)]cyanomethylene}-3-phenyl-5-substitu- ted 1,3,4-thiadiazolines were synthesized from hydrazonoyl halides and 4-{-2-aza-2-[(methylthiothioxomethyl)amino]vinyl}-2,3-dimethyl-1-phenyl-3-pyrazoin-5-one and 2-[4-(2,3-dimethyl-5-oxo-1-phenyl-3-pyrazolin-4-yl)-1,3-thiazol-2-yl]ethane-nitrile, respectively. All synthesize compounds were elucidated by elemental analysis, spectra, and alternative synthesis routes, whenever possible. 相似文献
104.
The present paper undertakes the study of (C12H12N)2CuCl4, which is a new hybrid compound. It is synthesized and characterized by single-crystal X-ray diffraction, Hirshfeld surface analysis, and FT-IR, FT-Raman, and impedance spectroscopies. It is crystallized in the monoclinic system with C2/c space group. Its crystal structure was determined and refined down to an R value of 0.05 and a wR value of 0.14. The structure can be described by the alternation of two different, cationic–anionic layers parallel to (110) plan. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (N–H…Cl, C–H…Cl) and π–π interactions. Hirshfeld surface analyses and fingerprint plots are used for decoding intermolecular interactions in the crystal network and contribution of component units for the construction of the 3D architecture. The presence of different functional groups and the nature of their vibrations were identified by FT-IR and FT-Raman spectroscopies. The material is characterized by impedance spectroscopy technique measured in 209–500 MHz frequency and 296–390 K temperature ranges. In addition, the Cole–Cole (Z? versus Z?) plots were well fitted to an equivalent circuit built up by a parallel combination of resistance (R) and constant phase elements (CPEs). The close values of activation energies obtained from the analysis of equivalent circuit data confirm that the transport is through ion hopping mechanism in the bis (4-benzylpyridinium) tetrachlorocuprate. 相似文献
105.
The non-centrosymmetric microporous fluorinated iron phosphate, (H3O)2[Fe4(H2O)2F4(PO4)2(HPO4)2](H2O), is endowed with properties. In fact, the thermogravimetric analysis study shows a mass loss evolution as a temperature function. The optical study was also examined by UV–vis absorption. The magnetic results reveal the appearance of a ferromagnetic behavior at low temperature (Tc = 11.64 K). 相似文献
106.
Banacer Himmi Saïd Kitane Abdelhamid Eddaif Jean‐Pierre Joly Fouzia Hlimi Mohamed Soufiaoui Abdelmejid Bahloul Abdelfatah Sebban 《Journal of heterocyclic chemistry》2008,45(4):1023-1026
107.
Sayed A. Ahmed Ahmed M. Hussein Walaa G. M. Hozayen Ahmed H. H. El‐Ghandour Abdou O. Abdelhamid 《Journal of heterocyclic chemistry》2007,44(4):803-810
108.
Abdulmalik S. Altamimi Adel S. El-Azab Sami G. Abdelhamid Mubarak A. Alamri Ashraf H. Bayoumi Safar M. Alqahtani Alhumaidi B. Alabbas Ali I. Altharawi Manal A. Alossaimi Menshawy A. Mohamed 《Molecules (Basel, Switzerland)》2021,26(10)
A new series of 8-methoxy-2-trimethoxyphenyl-3-substituted quinazoline-4(3)-one compounds were designed, synthesized, and screened for antitumor activity against three cell lines, namely, Hela, A549, and MDA compared to docetaxel as reference drug. The molecular docking was performed using Autodock Vina program and 20 ns molecular dynamics (MD) simulation was performed using GROMACS 2018.1 software. Compound 6 was the most potent antitumor of the new synthesized compounds and was evaluated as a VEGFR2 and EGFR inhibitor with (IC50, 98.1 and 106 nM respectively) compared to docetaxel (IC50, 89.3 and 56.1 nM respectively). Compounds 2, 6, 10, and 8 showed strong cytotoxic activities against the Hela cell line with IC50 of, 2.13, 2.8, 3.98, and 4.94 µM, respectively, relative to docetaxel (IC50, 9.65 µM). Compound 11 showed strong cytotoxic activity against A549 cell line (IC50, 4.03 µM) relative to docetaxel (IC50, 10.8 µM). Whereas compounds 6 and 9 showed strong cytotoxic activity against MDA cell line (IC50, 0.79, 3.42 µM, respectively) as compared to docetaxel (IC50, 3.98 µM). 相似文献
109.
Abdou O. Abdelhamid 《合成通讯》2017,47(15):1409-1414
A series of new 5-(heteroaryldiazenyl)thiazole incorporating pyrazole moiety have been synthesized through coupling of the thiazole with the appropriate heteroaryldiazonium salts. The newly synthesized compounds were characterized by elemental analysis, spectroscopic (IR, 1H NMR, and Mass) data, and alternative synthesis whenever possible. 相似文献
110.
Highly temperature responsive core-shell magnetic particles: synthesis, characterization and colloidal properties 总被引:1,自引:0,他引:1
Rahman MM Chehimi MM Fessi H Elaissari A 《Journal of colloid and interface science》2011,361(2):556-564
Three new dimeric cholesterol-based compounds of A(LS)(2) type, where A stands for aromatic component, S steroid moiety, and L a linker connecting the two units, have been designed and prepared. Gelation test in 30 solvents demonstrated that the compounds can gel some of the solvents and form 37 gels, of which 16 form spontaneously at room temperature (~25 °C). These gels possess smart thixotropic properties as revealed by rheological studies. FTIR and (1)H NMR measurements revealed that hydrogen bonding is an important driving force for the formation of the gel networks. XRD analysis demonstrated that unlike commonly found layered structures adopted by dimeric cholesterol-based low-molecular mass gelators (LMMGs), one of the gelators created in this study adopts a hexagonal packing structure in its benzene gel. 相似文献