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111.
Elaissi A Rouis Z Mabrouk S Salah KB Aouni M Khouja ML Farhat F Chemli R Harzallah-Skhiri F 《Molecules (Basel, Switzerland)》2012,17(3):3044-3057
The essential oils of fifteen Eucalyptus species harvested from the Jbel Abderrahman and Korbous arboreta (North East Tunisia) were screened for their antibacterial activities by the agar disc diffusion method. Eighteen major components as identified by GC/FID and GC/MS were selected for a study of the chemical and biological activity variability. The main one was 1,8-cineole, followed by spathulenol, trans-pinocarveol, α-pinene, p-cymene, globulol, cryptone, β-phellandrene, viridiflorol, borneol, limonene and isospathulenol. The chemical principal component analysis identified five species groups and subgroups, where each group constituted a chemotype, however that of the values of zone diameter of the inhibition (zdi) identified six groups of Eucalyptus oils, characterized by their antibacterial inhibition ability. The strongest activity was shown by E. platypus oil against Enterococcus faecalis and by E. lamannii oil against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. A correlation between the levels of some major components and the antibacterial activities was observed. 相似文献
112.
Speed S Vicente R Aravena D Ruiz E Roubeau O Teat SJ El Fallah MS 《Inorganic chemistry》2012,51(12):6842-6850
The syntheses, structural characterization, and magnetic behavior of two new hexanuclear copper(II) complexes derived from R-phosphonic acids and 1,3-bis(dimethylamino)-2-propanol (Hbdmap) with formulas [Cu(6)(μ-bdmap)(3)(μ(3)-Ph-PO(3))(2)(μ(3)-O···H···μ(3)-O)(ClO(4))(2)(H(2)O)]·5H(2)O (1) and [Cu(6)(μ-bdmap)(3)(μ(3)-t-Bu-PO(3))(2)(μ(3)-O···H···μ(3)-O)(μ(1,3)-dca)(dca)(H(2)O)]·6H(2)O (2) (Ph-H(2)PO(3) = phenylphosphonic acid, t-Bu-H(2)PO(3) = tert-butylphosphonic acid, dca = dicyanamide) are reported. Compounds 1 and 2 are hexanuclear 3.111 R-phosphonate(2-)/1,3-bis(dimethylamino)-2-propanolato(1-) cages including in the center the [μ(3)-O···H···μ(3)-O](3-) unit. The temperature dependence of the magnetic properties of 1 and 2 clearly indicates an overall strong antiferromagnetic coupling confirmed by DFT calculations. 相似文献
113.
Naceri Salah. E. Izerrouken M. Sari A. Ryelandt S. Menchi O. Ghamnia M. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):817-824
Journal of Radioanalytical and Nuclear Chemistry - Cold-worked zircaloy-4 was irradiated by 165 keV Ar ion at room temperature. The aim of the study is to understand the correlation... 相似文献
114.
115.
The nano-composites based on the burnt rice straw waste, reformed by nano-TiO2 and copper phthalocyanine (CuPc), namely, RSA-TiO2, RSA-CuPc, and RSA-TiO2-CuPc were prepared by a mechano-chemical method. The as-prepared composite systems were characterized by adopting FE-SEM, TEM, XRD, FTIR, SBET, and optical techniques. Their photo-catalytic performance in the degradation of methylene blue dye was evaluated under visible light irradiation. The co-existence of the two components in RSA, SiO2 and organic carbon, plus the inherently intimate contact between nano-TiO2 and CuPc could improve the photo-degradation of MB dye. The complete degradation of MB dye was achieved by using RSA-TiO2 (50) nano-composite and the time is taken for 50% degradation of a dye is 53 min under visible light radiation. The kinetic study revealed that photo-degradation of MB follows a pseudo-first-order reaction mechanism, where the kinetic rate constant was 0.013 min−1. 相似文献
116.
Erik L. Demeulemeester Willy S. Herroelen Salah E. Elmaghraby 《European Journal of Operational Research》1996
We describe two algorithms, based on dynamic programming logic, for optimally solving the discrete time/cost trade-off problem (DTCTP) in deterministic activity-on-arc networks of the CPM type, where the duration of each activity is a discrete, nonincreasing function of the amount of a single nonrenewable resource committed to it. The first algorithm is based on a procedure proposed by Bein, Kamburowski and Stallmann for finding the minimal number of reductions necessary to transform a general network to a series-parallel network. The second algorithm minimizes the estimated number of possibilities that need to be considered during the solution procedure. Both procedures have been programmed in C and tested on a large set of representative networks to give a good indication of their performance, and indicate the circumstances in which either algorithm performs best. 相似文献
117.
Excess molar enthalpies, measured at 298.15 K in a flow microcalorimeter, are reported for the five binary systems formed by mixing n-octane with n-hexane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane and 2,3-dimethylbutane. The results for equimolar mixtures, together with similar data for other n-alkane + hexane isomer mixtures, are correlated in terms of the acentric factors of the n-alkanes. 相似文献
118.
Nathalie Hild Salah Khodja Chantal Andraud Isabelle Ledoux Joseph Zyss Andr Collet 《Optics Communications》1998,150(1-6):223-229
Two chiral organic nonlinear optical materials, (3S,4S)-(−)-6-cyano-2,2-dimethyl-3,4-epoxychroman (1) and (3R,4R)-(+)-6-nitro-2,2-dimethyl-3,4-epoxychroman (2), have been grown into single crystals of cm3-size. Although both compounds crystallise in the orthorhombic P212121 space group, they are not isomorphous and their crystal packings are quite different. Angle tuned type II phase-matched second harmonic generation between 0.8 and 1.064 μm has been evidenced, with effective nonlinear coefficients deff of 1 and 5 pm/V at 0.96 μm for 1 and 2, respectively. These values are in agreement with those estimated in the oriented gas model approximation using EFISH first order hyperpolarisability values (β0=2.6 and 4.0×10−30 esu for 1 and 2, respectively). 相似文献
119.
Abdullah S. Babaqi Mohamed T. Mohamed Salah S. Massoud Mohamed F. Amira 《Transition Metal Chemistry》1988,13(3):201-204
Summary The aquation of chloropentamminecobalt(III) ion has been studied in ethylene glycol-water mixtures up to 80% by weight at five temperatures from 35 to 55°C. Specific solvent effects on the reaction rate and mechanism have been investigated and discussed. The validity of our previously proposed equations, correlating the specific reaction rate with the dielectric constant of the medium has been examined. The thermodynamic parameters of activation have been calculated and presented as evidence for the solvation effects and in support of the proposed reaction mechanism. 相似文献
120.
Lutz Lameyer Omar Abu Salah Stephan Deuerlein Thomas Stey Dietmar Stalke 《无机化学与普通化学杂志》2004,630(12):1801-1806
The magnesium, calcium, and strontium metal derivatives of 2, 2, 4, 4, 6, 6, 8, 8‐octamethylcyclotetrasilazane (OMCTS) have been synthesized and structurally characterized by X‐ray diffraction studies. These are the first complexes of the homologous series of alkaline earth metalated OMCTS. Similar to the homologous series of the corresponding alkali metal complexes, the structural properties show remarkable tendencies in the series from magnesium to strontium. The magnesium dication causes the most pronounced deformation along the transannular N‐···N‐ vector of the [(c‐N‐SiMe2‐NH‐SiMe2‐)2]2‐ dianionic ring. The lengths of the Si‐N bonds are correlated to the bond types, so that shorter distances result when the bonds become more ionic. The difference between the long Si‐N(H) bonds and the short Si‐N‐ bonds decreases gradually with the increasing mass of the alkaline earth metal dication. 相似文献