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91.
In this study, structural alterations in the biomolecular profile of the Cladonia convoluta exposed to lead were investigated considering the potential of lichens in biomonitoring practices. Particularly, qualitative and quantitative changes in the lipids, polysaccharides, proteins, and nucleic acids along with various organic acids in lead-exposed lichen were analytically analyzed using infrared spectroscopy. Moreover, the quantitative changes in chlorophyl and malondialdehyde levels were measured by independent biochemical assays. Chlorophyll content analysis revealed a dose- and time-dependent decrease in chlorophyl content, whereas malondialdehyde content analysis revealed lipid peroxidation as a result of lead exposure. Lead exposure diminished total nucleic acid quantity, which can be an important parameter for the elucidation of heavy metal tolerance mechanisms in lichens. Furthermore, lead exposure increased the quantity of usnic acid, signifying its importance in the lichen-based decontamination of metal polluted areas. 相似文献
92.
Özgür Delice Pınar Kirezli Dilek K. Çiftci 《General Relativity and Gravitation》2013,45(11):2251-2272
We consider a $D$ D dimensional Kasner type diagonal spacetime where metric functions depend only on a single coordinate and electromagnetic field shares the symmetries of spacetime. These solutions can describe static cylindrical or cosmological Einstein–Maxwell vacuum spacetimes. We mainly focus on electrovacuum solutions and four different types of solutions are obtained in which one of them has no four dimensional counterpart. We also consider the properties of the general solution corresponding to the exterior field of a charged line mass and discuss its several properties. Although it resembles the same form with four dimensional one, there is a difference on the range of the solutions for fixed signs of the parameters. General magnetic field vacuum solution are also briefly discussed, which reduces to Bonnor-Melvin magnetic universe for a special choice of the parameters. The Kasner forms of the general solution are also presented for the cylindrical or cosmological cases. 相似文献
93.
Ayhan Usta Mehmet Birey Nursen Sari Aliye Altundas Dilek Nartop 《Journal of Physical Organic Chemistry》2012,25(4):309-313
Ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxylate [C11H15NO2S] was synthesized by the Gewald method. Its single crystals were grown from an alcohol/ethyl acetate solution at 15 °C and characterized using IR and 1H‐NMR. These single crystals were irradiated for 72 h at 298 K by a 60Co gamma source with a dose speed of 0.864 kGy/h. After irradiation, electron spin resonance (ESR) measurements were carried out to study radiation‐induced radicals in the temperature range from 120 to 450 K. Additionally, for the single crystal, ESR angular dependencies were measured in the xy, xz and yz planes of the substance. This irradiated single crystal was analyzed based on the ESR spectra. Analysis of the spectra revealed that the radical was formed by a C–H bond fission at the carbon end of the substance. It was also observed that the color of the sample changed after irradiation. The hyperfine and g parameters were determined from the experimental spectra. It was inferred from these results that the hyperfine parameters and g value exhibited anisotropic behavior. The average values of these parameters were calculated as follows: g = 2.0088, AH1=H2 = 20.70 G, AH3=H4 = 10.80 G, AHa = 4.59 G, AHb = 3.24 G and, AN = 6.10 G. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
94.
95.
In this work, the dependence of the ethanol production using Saccharomyces cerevisiae 251TP(3-2) on calcium, sodium, and magnesium ion concentration and interaction effects were studied with the use of a statistical
experimental design. The parameters of the ethanol concentration model proposed on the basis of Box–Wilson experimental design
method were evaluated with the use of the experimental data. Comparison of the predicted values from the model with the experimentally
observed values showed that the model is a good fit. From the analysis of model equation, it was seen that sodium ion concentration
has significant main effects on ethanol production, and there is interactive effect only between calcium and magnesium. With
the use of developed model, maximum ethanol concentration of 3.73% (v/v) was obtained when calcium, sodium, and magnesium concentration were 1,515, 930, and 128 mg/L, respectively, for the 10%
sugar concentration in synthetic molasses. 相似文献
96.
In this study, acrylamide (AAm)/aconitic acid (ACA) copolymers were prepared with two different mol% of aconitic acid 4%, 17% and were irradiated with gamma irradiation at different irradiation doses (4 - 25kGy). The percent yield was assigned by gravimetrical method. The effect of irradiation dose, pH and involved amounts of monomers (AAm/ACA) in hydrogels on swelling properties were investigated. The conversion of monomers to hydrogels was 100% at 25kGy. Poly(acrylamide-co-aconitic acid) P(AAm/ACA) hydrogels have been used for the adsorption of some aqueous solutions of dyes such as Methylene Blue (MB) and Safranine-O (S). The hydrogels were swollen in distilled water at pH 3, 5, 7, 8 and in aqueous solutions of dyes. The initial swelling rates of hydrogels are increased by increasing of pH. The effects of concentration of the aqueous solutions of dye and hydrogel composition on the adsorption were investigated. The adsorption is increased and changed depending on the structure of dye and composition of hydrogel. 相似文献
97.
About 21 years after the Chernobyl accident, (137)Cs and (40)K activity concentration measurements using gamma-ray spectroscopy and elemental analysis using energy dispersive X-ray spectroscopy were performed in five different lichen species collected from the Giresun province of northeastern Turkey. Being a symbiosis of algae and fungi, lichens are mostly used for environmental measurements since the fungal partner is responsible for the uptake of necessary nutrients or harmful substances, such as heavy metals of radionuclides. The gamma activity results showed that (137)Cs, an artificial radionuclide released from the Chernobyl power plant accident, is still eminent in the environment of the province. The mean activity concentrations of (137)Cs and (40)K ranged from 24 to 254 with the mean value of 102 Bq kg(-1) and from 345 to 2103 with the mean value of 1143 Bq kg(-1) in dry weight. The results of the elemental analyses showed potassium, calcium, titanium, iron, tin, and barium in different concentrations. 相似文献
98.
99.
Determination of citalopram by capillary electrophoresis is described. Compounds were separated at 28 kV in 75 μm i.d. fused silica capillary tubing (total length 85 cm, effective length 65 cm) with 10 mM borate buffer, pH 8.5, containing 10% (v/v) methanol as running buffer. Citalopram and propylparaben (IS) appeared at 3.5 and 5.5 min, respectively. Repeatable linear results were obtained. The limits of detection and quantification were 5.73 × 10−6 and 1.72 × 10−5 M, respectively. When citalopram was determined in a pharmaceutical tablet by capillary electrophoresis and by a UV-spectrophotometric method differences between the results were not significant. The citalopram content of tablets was 100.8 ± 2.95% of the label claim. The amount found in serum was 26.7 ± 0.1% of the free drug, indicating that 73.3% of the drug was bound to protein. 相似文献
100.
The hydrothermal reaction of V2O5, V2O3, 2,2'-bpy and Na2SO4 in dilute sulfuric acid yields a novel hybrid, [VIVO(mu 3-SO4)(2,2'-bpy)]infinity, which demonstrates the potential of constructing a new class of robust composite solids composed of a (V/O/SO4)-based framework decorated with organic functionalities by combining appropriate vanadyl sulfate motifs with a variety of organic ligands. 相似文献