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31.
The objective of this study is to remove the phenol from aqueous solution by using the neutralized red mud in batch adsorption technique. The study was carried out as functions of contact time, pH, initial phenol concentration, red mud dosage and effect of salt addition. The experiments demonstrated that maximum phenol removal was obtained in a wide pH range of 1-9 and it takes 10 h to attain equilibrium. The adsorption data was analyzed using the Langmuir and the Freundlich isotherm models and it was found that the Freundlich isotherm model represented the measured sorption data well. The influence of addition of salt on phenol removal depends on the relative affinity of the anions for the red mud surface and the relative concentrations of the anions. 相似文献
32.
Elvan Üstün Aykut Özgür Kübra A. Coşkun Serpil Demir Düşünceli İsmail Özdemir Yusuf Tutar 《Transition Metal Chemistry》2017,42(4):331-337
Carbon monoxide is an important signaling molecule which is produced by heme oxygenase-1. CO shows antiproliferative activity against cancer cells; hence, activation of HO-1 is a significant inhibition strategy against tumor formation and survival of cancer cells. In this work, manganese-based CO-releasing molecules (CORMs) were designed and synthesized to inhibit breast cancer cell proliferation. Human invasive ductal breast cancer cells (MCF-7) were treated with the synthesized CORMs to investigate the effect of the complexes on breast cancer survival under UV light. In vitro experiments indicated that the complexes inhibited breast cancer cell proliferation, and further, the antiproliferative effects were increased under UV light. Thus, these novel CORMs may provide a drug template for the treatment of invasive ductal breast cancer. 相似文献
33.
In this study, thermally developing laminar forced convection in a pipe including viscous dissipation and wall conductance
is investigated numerically. The constant heat flux is assumed to be imposed at the outer surface of the pipe wall. The finite
volume method is used. The distributions for the developing temperature and local Nusselt number in the entrance region are
obtained. The dependence of the results on the Brinkman number and the dimensionless thermal conductivity are shown. The viscous
heating effect on the wall is shown. Significant viscous dissipation effects have been observed for large Br. 相似文献
34.
We introduce a version of the weighted 1-maximin problem in a convex polygon, where the weights are functions of a parameter. The 1-maximin problem is applicable in the location of undesirable facilities. Its objective is to find an optimal location such that the minimum weighted distance to a given set of points is maximized. We show that the parametric 1-maximin problem is equivalent to a 1-minimax problem, where the costs are non-linearly decreasing functions of distance. Using different values of the parameter in the 1-maximin problem, one can model different disutility functions for the users of the facility. Furthermore, the parameterization provides for a systematic way of reducing the effects of the weights, resulting in the unweighted 1-maximin problem in the limit. For two example problems we construct the optimal trajectory as a function of the parameter, and demonstrate that the trajectory may be discontinuous. 相似文献
35.
The electrical conductivity, Seebeck coefficient, and Hall coefficient of three-micron-thick films of amorphous Ge2Sb2Te5 have been measured as functions of temperature from room temperature down to as low as 200 K. The electrical conductivity manifests an Arrhenius behavior. The Seebeck coefficient is p-type with behavior indicative of multi-band transport. The Hall mobility is n-type and low (near 0.07 cm2/V s at room temperature). 相似文献
36.
M. Emin Erdo
an 《International Journal of Non》1999,34(6):660
An exact solution of the Navier–Stokes equations is obtained for the flow between two eccentric disks rotating with the same angular velocity and one of them executing non-torsional oscillations. An analytical solution describing the flow at large and small times after the start is given. The solutions depend on the ratio of the frequency of oscillation to the angular velocity of the disks and the ratio of the amplitude of oscillation to the angular velocity of the disks and to the distance between the axes of rotation, and the Reynolds number based on the distance between the disks and the angular velocity of the disks. The solutions for three cases when the angular velocity is greater than the frequency of oscillation or it is smaller than the frequency or it is equal to the frequency are discussed. 相似文献
37.
Mustafa Özdemir 《Heat and Mass Transfer》2007,43(6):527-534
This paper presents some experimental results of an extensive research on a novel oscillating heat pipe. The heat pipe is
formed of three interconnected columns as different from the pulsating heat pipe designs. The dimensions of the heat pipe
considered in this study are large enough to neglect the effect of capillary forces. Thus, the self-oscillation of the system
is driven by the gravitational force and the phase lag between the evaporation and condensation processes. The overall heat
transfer coefficient is found to be approximately constant irrespective of heat load for the experimental cases considered.
The results are also compared with the previously published data by other investigators for water as the working fluid and
for the same heat input range. The experimental data for the time variation of the liquid column heights and the vapor pressure
are correlated algebraically, convenient for practical uses. 相似文献
38.
The use of highly purified immunoglobulin became among the most powerful adopted strategies in therapeutic trials nowadays. Their role as immunomodulatory and anti-inflammatory agents has widened their scope of use. A novel continuous supermacroporous monolithic cryogels embedded with histidine-epoxy-activated-sepharose beads were synthetized as a new monolithic adsorbents for the separation of immunoglobulin G from human serum. The histidine-epoxy-activated-sepharose beads were embedded into the 2-hydroxyethyl methacrylate (HEMA) cryogels present in frozen aqueous solution inside a plastic syringe. The microstructure morphology of the cryogels was characterized by swelling measurement and scanning electron microscopy. The adsorption of human IgG on the histidine-epoxy-activated-sepharose beads pHEMA cryogels appeared to follow the Langmuir–Freundlich adsorption isotherm model. The maximum IgG adsorption was observed at 4°C and pH 7.4 and was found to be 26.95 mg/g of cryogel which is close to that obtained experimentally (24.49 mg/g). The cryogels were used for several adsorption-desorption cycles without any negligible decrease in their adsorption capacity. 相似文献
39.
We introduce a new solution concept for -person bargaining problems, which can be considered as the dual of the Equal-Area solution (EA) (see Anbarc? and Bigelow (1994)). Hence, we call it the Dual Equal-Area solution (DEA). We show that the point selected by the Kalai–Smorodinsky solution (see Kalai and Smorodinsky (1975)) lies in between those that are selected by EA and DEA. We formulate an axiom–area-based fairness–and offer three characterizations of the Kalai–Smorodinsky solution in which this axiom plays a central role. 相似文献
40.
Cemal Özeroğlu Emine Doğan Gönül Keçeli 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):577-586
In this study, a crosslinked copolymer bearing sodium methacrylate functional groups has been proposed to remove Cs(I) ions
from aqueous solutions. For this purpose, the crosslinked copolymer of ethylene glycol dimethacrylate (EGDM) and methacrylic
acid (MA) containing 25% MA as weight percentage was synthesized by using benzoyl peroxide (BPO)-N,N-dimethyl aniline initiator system. The available carboxyl groups in copolymer were converted to the groups of sodium methacrylate
using 2 N NaOH. The adsorption behavior of cesium ions on the densely crosslinked poly(sodium methacrylate) from aqueous solutions
were investigated by the technique of ICP-MS measurements of cesium ions in solutions. Batch adsorption method was used to
analyze the Cs(I) adsorption as a function of parameters such as the amount of adsorbent, contact time, pH of solution, initial
Cs(I) concentration and temperature. The adsorption data were evaluated by the Freundlich, Langmuir and Dubinin–Radushkevich
(D–R) isotherms. The adsorption capacity and free energy change were calculated by using D–R isotherm. The adsorption data
obtained from experimental results have been tested by the fractional power, the Elovich, the pseudo-first order and the pseudo-second
order kinetic models. 相似文献