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101.
Elmastaş M Turkekul I Oztürk L Gülçin I Isildak O Aboul-Enein HY 《Combinatorial chemistry & high throughput screening》2006,9(6):443-448
The ethanol extracts of Morchella vulgaris (EEMV) and Morchella esculanta (EEME) were analysed for their antioxidant activities in different systems including reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, and metal chelating activity. EEMV and EEME had similar reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activity at concentrations of 50, 100, and 150 microg/mL. These various antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and alpha-tocopherol. The percent inhibition of different concentrations of EEMV on peroxidation in the linoleic acid system was 85 and 87 % respectively, which was greater than that of 100 and 250 microg/mL of alpha-tocopherol (50 and 77%, respectively) and similar to 250 microg/mL of BHA (85, 87%, respectively). The percent inhibition of different concentrations of EEME on peroxidation in the linoleic acid system was 80 and 87 % respectively, which was greater than that of 100 and 250 microg/mL of alpha-tocopherol (50, 77%) and similar to 250 microg/mL BHA (87%). On the other hand, the percent inhibition of 100 and 250 microg/mL of BHT was 97 and 99%, respectively. In addition, the total phenolic compounds in EEMV and EEME were determined as gallic acid equivalents. 相似文献
102.
Applications of fractional complex transform and $\left( \frac{G^{\prime }}{G}\right) $-expansion method for time-fractional differential equations
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Ahmet Bekir Ozkan Guner Omer Unsal Mohammad Mirzazadeh 《Journal of Applied Analysis & Computation》2016,6(1):131-144
In this paper, the fractional complex transform and the $\left( \frac{G^{\prime }}{G}\right) $-expansion method are employed to solve the time-fractional modfied Korteweg-de Vries equation (fmKdV),Sharma-Tasso-Olver, Fitzhugh-Nagumo equations, where $G$ satisfies a second order linear ordinary differential equation. Exact solutions are expressed
in terms of hyperbolic, trigonometric and rational functions. These solutions may be useful and desirable to explain some nonlinear physical phenomena in genuinely nonlinear fractional calculus. 相似文献
103.
104.
The existence of the weak limit as n of the uniform measure on rooted triangulations of the sphere with n vertices is proved. Some properties of the limit are studied. In particular, the limit is a probability measure on random triangulations of the plane. 相似文献
105.
Platelet-derived microparticles (PMPs) formed by vesiculation during platelet activation seem to play a role in blood coagulation and in pathological disease states. Flow cytometry is currently the gold standard to characterize platelets and PMPs. Using this technique we distinguished between platelets and PMPs based on size and the presence of phosphatidyl serine (PS); PMPs were arbitrarily defined to be smaller than one micrometer and capable of forming a stable complex with fluorescently-labeled Annexin V, a protein that forms a calcium-dependent complex with PS. Further confirmation of PMP and platelet identity was done by use of fluorescently-labeled antibodies against CD41a, a glycoprotein found on the surface of both platelets and PMPs. In this report we also introduce the use of capillary electrophoresis with post-column laser-induced fluorescence detection (CE-LIF) for the analysis of fluorescently labeled platelets and PMPs. While both flow cytometry and CE-LIF can measure individual fluorescent events, only CE-LIF allowed us to calculate individual electrophoretic mobilities of activated platelets and PMPs that were then represented as distributions. A comparison between distributions suggests that PMPs have less negative mobilities. The fact that activated platelet preparations include PMPs partially obscure the interpretation of the data. While PMP and platelet number ml(-1) determined by flow cytometry is lower than the same parameter determined by CE-LIF, signal-to-noise ratio was 20 fold better for flow cytometry than for CE-LIF. This is the first time that a direct comparison between these two techniques is reported. 相似文献
106.
Yilmaz Veysel T. Hamamci Sevim Andac Omer Thöne Carsten Harrison William T.A. 《Transition Metal Chemistry》2003,28(6):676-681
Mono- and binuclear copper(II) saccharinate (sac) complexes containing 2-pyridinepropanol (pypr) have been prepared and characterized by elemental analyses, i.r., u.v.–vis., magnetic measurements and single crystal X-ray diffraction. The copper(II) ion in trans-[Cu(pypr)2(sac)2] has –1 site symmetry and is octahedrally coordinated by two bidentate neutral pypr (N, O) and two sac (O) ligands. The binuclear copper(II) complex, [Cu2(-pypr)2(sac)2], is built up around a centre of symmetry and contains two strongly distorted square–planar coordinated copper(II) ions bridged by two alkoxo groups of the deprotonated pypr ligand, which also coordinates to the copper(II) ions through its nitrogen. In contrast to the mononuclear complex, the sac ligands in the binuclear complex is N-coordinated. The binuclear complex exhibits diamagnetic behaviour. The i.r. spectra and thermal decompositions of both complexes are described. 相似文献
107.
Omer Sahin Fevzi Aslan Mustafa Ozdemir Mustafa Durgun 《Journal of Crystal Growth》2004,270(3-4):604-614
Growth rate of polycrystalline disc of borax compressed at different pressure and rotated at various speed has been measured in a rotating disc crystallizer under well-defined conditions of supersaturation. It was found that the mass transfer coefficient, K, increased while overall growth rate constant, Kg, and surface reaction constant, kr, decreased with increasing smoothness of the disc. It was also determined that kinetic parameters (kr,r,K,g) of crystal growth rate of borax decreased with increasing rotating speed of the polycrystalline disc. The effectiveness factor was calculated from the growth rate data to evaluate the relative magnitude of the steps in series bulk diffusion through the mass transfer boundary layer and the surface integration. At low rotating speed of disc, the crystal growth rate of borax is mainly controlled by integration. However, both diffusion and integration steps affect the growth rate of borax at higher rotating speed of polycrystalline disc. 相似文献
108.
Perwez Alam Omar M. Noman Rashed N. Herqash Omer M. Almarfadi Ali Akhtar Ali S. Alqahtani 《Molecules (Basel, Switzerland)》2022,27(1)
In this study, ultrasound-assisted extraction conditions were optimized to maximize the yields of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol from S. alexandrina (aerial parts). The three UAE factors, extraction temperature (S1), extraction time (S2), and liquid to solid ratio (S3), were optimized using response surface methodology (RSM). A Box–Behnken design was used for experimental design and phytoconstituent analysis was performed using high-performance liquid chromatography-UV. The optimal extraction conditions were found to be a 64.2 °C extraction temperature, 52.1 min extraction time, and 25.2 mL/g liquid to solid ratio. The experimental values of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol (2.237, 12.792, 2.457, 0.261, and 1.529%, respectively) agreed with those predicted (2.152, 12.031, 2.331, 0.214, and 1.411%, respectively) by RSM models, thus demonstrating the appropriateness of the model used and the accomplishment of RSM in optimizing the extraction conditions. Excellent antioxidant properties were exhibited by S. alexandrina methanol extract obtained using the optimized extraction conditions with a DPPH assay (IC50 = 59.7 ± 1.93, µg/mL) and ABTS method (47.2 ± 1.40, µg/mL) compared to standard ascorbic acid. 相似文献
109.
Omer Andac Yildiray Topcu Veysel T. Yilmaz Kutalmis Guven 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1381-1384
The structures of the title triethanolamine (tea) complexes of CdII and HgII saccharinates, bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-cadmium(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Cd(C6H15NO3)2](C7H4NO3S)2, (I), and bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-mercury(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Hg(C6H15NO3)2](C7H4NO3S)2, (II), or [M(tea)2](sac)2, where M is CdII or HgII and sac is the saccharinate anion, reveal seven-coordinate metal ions in both complexes. Both complex cations, [M(tea)2]2+, adopt a monocapped trigonal prism geometry in which the two tea ligands exhibit different coordination modes to achieve seven-coordination. One tea ligand acts as a tetradentate ligand using all its donor atoms, while the other behaves as a tridentate O,N,O′-donor ligand, with one of its ethanol groups remaining uncoordinated. The H atoms of the free and coordinated hydroxyl groups of the tea ligands are involved in hydrogen bonding with the amine N atom, and with the carbonyl and sulfonyl O atoms of neighbouring sac ions, forming an infinite three-dimensional network. A weak π–π interaction between the phenyl rings of the sac ions also occurs. 相似文献
110.
Water adsorbed on Ni(1 1 1) forms an ordered, hydrogen bonded ice structure with a (2√7 × 2√7)R19° unit cell. The 2√7 wetting structure forms as islands and persists up to saturation of the first layer. Adsorption of a fraction of a monolayer more water into a second layer destroys the 2√7 registry and creates a disordered ice film. Gas adsorption measurements indicate that the wetting layer is completely covered by a second layer of water before thicker multilayer ice forms. As the second layer is completed the film orders to form an incommensurate crystalline ice film with a hexagonal LEED pattern, oriented to the Ni close packed rows. This ordered, incommensurate structure persists as the ice multilayer grows thicker. 相似文献