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361.
Ismet Sahin Yasar A. Ozcan Hacer Ozgen 《Central European Journal of Operations Research》2011,19(1):19-37
The purpose of this research is to explore the operational performance of the Ministry of Health’s general public hospitals
following the implementation of the Health Transformation Program in Turkey. This study adopts the Malmquist index to analyze
the operational performance of the 352 Ministry of Health’s general hospitals during the period 2005–2008. The result show
that the operational performance of these hospitals regardless of the attributes present a common tendency that the performance
of 2005–2007 progressed as compared to the previous year, while that of 2008 has regressed as compared to 2007. 相似文献
362.
Gorkem Sahin Aylin Ziylan Albayrak Zeynep SaraylI Bilgici Duygu Avci 《Journal of polymer science. Part A, Polymer chemistry》2009,47(7):1953-1965
Novel dental monomers containing both phosphonic and carboxylic acid functional groups were prepared. The monomers were based on t‐butyl α‐bromomethacrylate (t‐BuBMA) and synthesized in three steps: The reaction of o‐hydroxyaryl phosphonates [diethyl (2‐hydroxyphenyl) phosphonate, tetraethyl (2,5‐dihydroxy‐1,4‐phenylene) diphosphonate and tetraethyl 5,5′‐(propane‐2,2‐diyl)bis(2‐hydroxy‐5,1‐ phenylene) diphosphonate] with t‐BuBMA, the hydrolysis of phosphonate groups to phosphonic acid using trimethyl silylbromide, and the hydrolysis of the t‐butyl groups to carboxylic acid with trifluoroacetic acid. The monomers were solids and soluble in water and ethanol. The structures of the monomers were determined by Fourier transform infrared (FTIR), 1H, 13C, and 31P nuclear magnetic resonance (NMR) spectroscopy. The copolymerization behaviors of the synthesized monomers with glycerol dimethacrylate were first investigated in bulk using photodifferential scanning calorimetry at 40 °C with 2,2′‐dimethoxy‐2‐phenyl acetophenone as photoinitiator. Then, the solution copolymerization of the monomers with acrylamide in ethanol and water was studied, indicating that the synthesized monomers are incorporated into the copolymers. The acidic nature of the aqueous solutions of these monomers (pH values 1.72–1.87) is expected to give them etching properties important for dental applications. The interaction of the monomers with hydroxyapatite was investigated using 13C NMR and FTIR techniques. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1953–1965, 2009 相似文献
363.
Seda Edizer Gorkem Sahin Duygu Avci 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5737-5746
Five novel phosphonated mono‐ and dimethacrylate monomers have been synthesized by two different routes. Monomers 1 and 2 were synthesized by reactions of methacryloyl chloride with diethyl (2‐hydroxyphenyl) phosphonate or tetraethyl (2,5‐dihydroxy‐1,4‐phenylene) bisphosphonate; monomers 3 and 4 by reactions of α‐(chloromethyl)acryloyl chloride (CMAC) first with dimethyl (2‐hydroxyethyl) phosphonate and then with benzoic or formic acids. The reaction of CMAC with two moles of dimethyl (2‐hydroxyethyl) phosphonate gave monomer 5 . Thermal homopolymerization of monomers 1 , 3 , 4 , and 5 and copolymerization of monomer 1 with methyl methacrylate (MMA) were investigated using azobisisobutyronitrile (AIBN) at 60 °C. Glass transition temperatures were observed for poly‐ 1 , poly(MMA‐co‐ 1 ) (50:50), poly(MMA‐co‐ 1 ) (90:10), PMMA, poly‐ 3 , and poly‐ 5 at 52, 90, 99, 129, 50, and 70 °C, respectively. TGA analysis of these polymers indicated formation of char on combustion. Homo‐ and/or copolymerization behavior of the synthesized monomers with 2,2‐bis[4‐(2‐hydroxy‐3‐methacryloyloxy propyloxy) phenyl] propane (Bis‐GMA) were investigated with photodifferential scanning calorimetry. The maximum rate of polymerizations decreased in the following order: Bis‐GMA~ 3 > 1 > 4 > 5 . The conversions of monomers 1 , 3 , 4 , and 5 (73.9, 85.9, 98.2, and 62.2%) were very high compared with Bis‐GMA (40.5%). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5737–5746, 2009 相似文献
364.
365.
This paper examines a Newsvendor framework in which a wholesaler who sells products to retailers is subject to inaccuracies in inventory data. The wholesaler’s decision regarding the management of his warehouse inventory is based on inventory data recorded in the information system. We assume that the wholesaler uses barcode labels and scanners in order to gather information concerning the available inventory in the warehouse. Because of errors arising during the manual barcode scanning process, the information on the available inventory level can deviate from the physical quantity and can result in an additional cost. This paper quantifies the economic impact of having uncertainty on the inventory level. We first analyze the case of a wholesaler that is not aware of inventory errors or chooses to ignore them in order to evaluate the efficiency loss due to errors compared with an error free situation. We then assess the effect of various actions enabling to tackle the inventory inaccuracy issue with a particular focus on actions such as the deployment of a new data capture technology. 相似文献
366.
The classic analysis of Rayleigh light scattering (LS) is re-examined for multi-component protein solutions, within the context of Kirkwood-Buff (KB) theory as well as a more generalized canonical treatment. Significant differences arise when traditional treatments that approximate constant pressure and neglect concentration fluctuations in one or more (co)solvent/co-solute species are compared with more rigorous treatments at constant volume and with all species free to fluctuate. For dilute solutions, it is shown that LS can be used to rigorously and unambiguously obtain values for the osmotic second virial coefficient (B(22)), in contrast with recent arguments regarding protein interactions deduced from LS experiments. For more concentrated solutions, it is shown that conventional analysis over(under)-estimates the magnitude of B(22) for significantly repulsive(attractive) conditions, and that protein-protein KB integrals (G(22)) are the more relevant quantity obtainable from LS. Published data for α-chymotrypsinogen A and a series of monoclonal antibodies at different pH and salt concentrations are re-analyzed using traditional and new treatments. The results illustrate that while traditional analysis may be sufficient if one is interested in only the sign of B(22) or G(22), the quantitative values can be significantly in error. A simple approach is illustrated for determining whether protein concentration (c(2)) is sufficiently dilute for B(22) to apply, and for correcting B(22) values from traditional LS regression at higher c(2) values. The apparent molecular weight M(2, app) obtained from LS is shown to generally not be equal to the true molecular weight, with the differences arising from a combination of protein-solute and protein-cosolute interactions that may, in principle, also be determined from LS. 相似文献
367.
Czechoslovak Mathematical Journal - Let χ be a nonprincipal Dirichlet character modulo a prime number p ? 3 and let $${\mathfrak{a}_{\cal X}}: = {1 \over 2}\left( {1{ - _{\cal X}}\left(... 相似文献
368.
Expanded bodipy dyes: anion sensing using a bodipy analog with an additional difluoroboron bridge 总被引:1,自引:0,他引:1
Oxalyl-tethered pyrroles can be doubly bridged with two difluoroboron chelating units to yield bright orange dyes. Interestingly, in polar organic solvents, the addition of fluoride and cyanide result in reversible detachment of the otherwise stable difluoroboron bridges, resulting in sharp changes in color. Thus, this novel compound behaves as a highly selective chromogenic sensor for fluoride and cyanide ions. 相似文献
369.
Sahin M Koca A Ozdemir N Dinçer M Büyükgüngör O Bal-Demirci T Ulküseven B 《Dalton transactions (Cambridge, England : 2003)》2010,39(42):10228-10237
The stable uranyl complexes, [UO(2)(L)C(9)H(19)OH], were obtained from 3,5-dichlorosalicyl-(L(I)) and salicyl-aldehyde-S-propyl-thiosemicarbazones (L(II)) with substituted-salicylaldehyde in nonyl alcohol. The structures of the complexes have been characterized by elemental analysis, IR, (1)H NMR, conductivity, magnetic moment measurements, cyclic voltammetry, thermal gravimetric analysis and single crystal X-ray diffraction technique. The U(VI) centre is seven-coordinated in a distorted pentagonal bipyramidal geometry. The relative orientations of the nonyl alcohol and S-propyl group in the title complexes are completely different due to different crystal packing. Electrochemical behaviors of the thiosemicarbazone ligands and the uranyl complexes were studied using cyclic voltammetry and square wave voltammetry. Redox processes of the compounds are significantly influenced by the central metal ions and the nature of substituents on the thiosemicarbazones, which are important factors in controlling the redox properties. In situ spectroelectrochemical studies were employed to determine the colors and spectra of electro-generated species of the complexes. 相似文献
370.
Undoped and doped Cadmium oxide (CdO) films with different Mn concentrations were prepared on glass substrates by the successive ionic layer adsorption and reaction method and annealed at two different temperatures. Structural, morphological and optical conditions were performed by XRD, scanning electron microscope (SEM) and UV–vis spectrum measurements. The deposited films were dense and they adhere well to the glass substrates. From the SEM photographs, it was seen that Mn doping concentration and annealing process affect the morphologies of the nanostructures. It was found that the growth process modifies the microstructures of the CdO films. XRD results and UV–vis analysis reveal that the crystal structure and optical band gap of the films could be adjusted by varying the Mn concentration and annealing temperature. The results also indicate that there is a direct dependence of the physical and optical properties of the metal oxide films on doping concentration and annealing process. 相似文献