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51.
Ghaferah H. Al-Hazmi Asmaa A. Ibrahim Moamen S. Refat Farouk A. Adam Ahmed Allam Sonam Shakya Amnah Mohammed Alsuhaibani 《印度化学会志》2022,99(8):100605
The interaction of chlorothiazide (CH) as donor (D) with picric acid (PA) and iodine (I2) as π- and σ-acceptors (A), respectively, gives charge-transfer (CT) complexes as a final products. The reaction of donor and acceptors were studied spectrophotometrically. The complexes are generally of the n-π* and n-σ* types, with the ground state wave function primarily characterized by the non-bonding structure. For the micro determination of chlorothiazide using picric acid and iodine as acceptors, the ideal conditions encouraging the formation of complexes are thoroughly explored. It was discovered that the stoichiometry of the molecular structure is 1:1 (D:A). The equilibrium constant and the molar extinction coefficient were calculated using Benesi-Hildebrand and its modifications. DFT/TD-DFT calculations with B3LYP/LanL2DZ and 6-311G++ level of theory were used to provide comparable theoretical data along with electronic energy gap of HOMO→LUMO. Molecular docking calculations have been performed between CT complexes and Covid-19 protease (6LU7) to study the interaction between them and their inhibitory effect. 相似文献
52.
S. H. Kandil M. A. El-Gamal 《Journal of polymer science. Part A, Polymer chemistry》1986,24(11):2765-2771
Methyl acrylate–styrene copolymers of different copolymer compositions were free-radically prepared. The relative intensities of the carbonyl frequencies of the methyl acrylate units at v 1730 cm?1 were correlated with the copolymer composition. The positions and shapes of the carbonyl bands in the infrared absorption spectra of the copolymers-dissolved in chloroform, were shown to depend on the composition of the copolymers and upon the presence of different proportions of methyl acrylate centered triads. The results obtained by infrared spectroscopy were compared with those obtained by 13C-NMR. Infrared spectra may be used to yield information about both the copolymer composition and the triad sequence distribution. 相似文献
53.
M. E. Kassem E. F. El-Wahidy S. H. Kandil M. A. El-Gamal 《Journal of Thermal Analysis and Calorimetry》1984,29(2):325-331
Thermal analysis, DTA, TG, TMA and DSC were performed on LiKSO4 in the temperature range 300 to 800 K, using a Heraeus TA 500 thermal analyser. The thermal expansion coefficients measured along the three fundamental crystallogrpahic axes, together with the specific heatC p, show anomalous behaviour around the phase transition temperature of these crystals atT c=705 K. Anisotropy in the thermal expansion coefficient as well as endothermic peaks aroundT c were also observed, while no loss of weight was detected. The temperature-dependence of the thermal conductivity of LiKSO4 crystals has been estimated, using the temperature-variation of the thermal diffusivity. 相似文献
54.
S. S. Kandil F. I. Abdel-Hay R. M. Issa 《Journal of Thermal Analysis and Calorimetry》2001,63(1):173-180
The thermal decompositions of cobalt(II), nickel(II) and copper(II) complexes of4-(3'-sulfonylazido-6'-methoxyphenylazo)-1-phenyl-3-methyl-2-pyrazolin-5-one H(D1–SO2N3) and 4-(4'-sulfonylazido phenylazo)-3-phenyl-3-methyl-2-pyrazolin-5-one H(D2–SO2N3) were studied by thermogravimetry. The decomposition in all cases takes place along two stages. The first stage is due to the elimination of water and nitrogen molecules with the formation of tetracoordinate complexes containing nitrene reactive species[M(DSO2N:)2]. The second stage represents the decomposition of the material to the metal oxide. The kinetics of the decomposition were examined by using Coats–Redfern, the decomposition in all complexes was found to be first order for the first and second stages. The activation energies and other activation parameters (H* and S* and G*) were computed and related to the bonding and stereochemistry of the complexes.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
55.
Yousuf A. Al-Farkh Farouk H. Al-Hajjar Hayat S. Hamoud 《Journal of heterocyclic chemistry》1979,16(1):1-6
3-Aryl-1-phenyl-2-propen-1-one I reacted with ethyl phenylacetate (II) in the presence sodium ethoxide at room temperature to give the corresponding ethyl β-aryl-γ-benzoyl-α-phenyl-butyrate III. However,' when the same ketones were refluxed with ethyl phenylacetate, they gave the corresponding 4-aryI-3,6-diphenyl-3,4-dihydro-2H-pyran-2-ones IV. The reactions of III and IV with hydrazine hydrate afforded the corresponding hydrazones VI and 2-pyridones VIII, respectively. The structure and configuration of the products are based on chemical and spectroscopic evidence. 相似文献
56.
Gaber A. Elinany Fikry M. Ebeid Ahmed M. Zahra Farouk I. Ziedan 《Journal of Electroanalytical Chemistry》1976,72(3):363-369
The polarographic behavior of metal ions in perchlorate media containing gallic acid is described. Tungsten(VI) forms a complex with gallic acid which yields a single wave in these media, useful in the polarographic determination of tungsten. Evidence for complexation of chromium(III), copper(II), iron(III), molybdenum(VI), uranium(VI), vanadium(V), tungsten(VI), praseodymium(III), samarium(III), neodymium(III) and gadolinium(III) is obtained and the behavior of these metal ions is summarized. 相似文献
57.
3-Aryl-1-phenyl-2-propen-1-ones Ia-f and aroylphenylacetylenes Va-d reacted under reflux for 3 hours with cyanoacetamide in the presence of sodium ethoxide to give the corresponding 4-aryl-3-cyano-6-phenyl-2-(1H)pyridones VI. However, when ketones Ia-e were refluxed with cyanoacetamide for one hour in the presence of sodium ethoxide or piperidine, they gave the corresponding 4-aryl-3-cyano-3,4-dihydro-6-phenyl-2-(1H)pyridones IIIa-e, which upon heating with selenium gave the corresponding 2-pyridones VI. The structures of the products are based on chemical and spectroscopic evidence. 相似文献
58.
Farouk Badrakhan 《International Journal of Non》1977,12(1):1-7
On the basis of a geometrical interpretation of the method of first harmonic of Haag—Krylov—Bogolioubov—Mitropolski, a new dynamical study of an oscillator with hysteresis is made. This consists in replacing the equation of motion by another approximate equation which conserves the nonlinearity of the original equation. This method is valid in the case of sinusoidal excitation, but it can be extended to the case of random excitation. In particular, in the case when this excitation is white noise the Fokker—Planck equation for the system can be written down with the help of certain assumptions which are physically realisable. Hence, all useful information concerning the response can be derived. 相似文献
59.
Experimental and numerical results are presented from investigations into the hydrodynamics of a bench scale bubble column reactor. Countercurrent bubble column reactors are most commonly used in water disinfection for effecting mass transfer of ozone to the aqueous phase. In the reactor column used in this study, gas is introduced at the bottom of the column via a spherical diffuser and water is introduced to the top of the column through a manifold packed with glass spheres. Residence time distribution (RTD) studies were conducted for a range of gas flow rates chosen to span the dispersed flow bubble regime. A multiphase computational fluid dynamics (CFD) model was used to simulate the flow in the bubble column and to gain insights into the fluid dynamics of countercurrent flow bubble columns. The CFD model accurately predicted trends in mixing. Use of CFD in bubble column design and scale-up thus may yield better designs than those based on empirical relations. 相似文献
60.
Tasneem Mokhtar Radwan Maher Abdel-Aziz El-Hashash Ashraf Abdel-Hamid Farouk Wasfy Suzan Abdelhalim Abdallah 《Journal of heterocyclic chemistry》2020,57(3):1111-1122
Heterocyclic compounds with different heterocycle moieties, namely benzoxazinone, benzimidazole, quinazolinone, and benzofuranone heterocyclic rings, were synthesized, characterized, and evaluated for their anticancer activity against human hepatocellular carcinoma cell line (HepG2) using sulforhodamine B (SRB) and dimethylthiazol-diphenyltetrazolium bromide (MTT) assays. Also, their cytotoxic activities were tested against human epithelioid carcinoma (Hela) cell line in comparison with normal cell, amniotic epithelial (WISH) cell line, as an in vitro toxicity estimation model. The results showed clearly that 2-(2-benzyl-4-oxoquinazolin-3(4H)-yl)acetohydrazide 4 is the most potent antioxidant and anticancer agents. Although, 3-amino-2-benzylquinazolin-4(3H)-one 5 is less potent anticancer agent against Hela but it is more safe against normal cell (WISH). 相似文献