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991.
S.S. Shinde 《Materials Research Bulletin》2011,46(10):1734-1737
A metal-semiconductor-metal photoconductive detector was fabricated using high quality Ga-doped ZnO film epitaxially grown onto alumina substrate by spray pyrolysis. The photocurrent increases linearly with incident power density for more than two orders of magnitude. Reflectance and photocurrent measurements were carried out to study optoelectronic properties of Ga-doped ZnO thin film. Both spectra are consistent with each other showing good response in UV than visible region. Peak responsivity of about 1187 A/W at 5 V bias for 365 nm light was obtained in UV region. 相似文献
992.
Dipankar Saha 《Materials Research Bulletin》2011,46(8):1252-1256
The facile method of solution combustion was used to synthesize γ(L)-Bi2MoO6. The material was crystallized in a purely crystalline orthorhombic phase with sizes varying from 300 to 500 nm. Because the band gap was 2.51 eV, the degradation of wide variety of cationic and anionic dyes was investigated under solar radiation. Despite the low surface area (<1 m2/g) of the synthesized material, γ(L)-Bi2MoO6 showed high photocatalytic activity under solar radiation due to its electronic and morphological properties. 相似文献
993.
Hematite solid spindles and hollow spindles have been selectively synthesized by a template-free, economical hydrothermal method, using FeCl3·6H2O as the starting materials and NaOH as the homogeneous precipitant. XRD analyses indicated that the products consisted of α-Fe2O3. SEM and TEM measurements showed that the morphologies of products were in the shape of solid spindles and hollow spindles, respectively. A possible formation process based on the nucleation-oriented aggregation-recrystallization mechanism is proposed. Moreover, the as-prepared hollow spindle-like α-Fe2O3 exhibits a good response and reversibility to some organic gas, such as 2-propanol and acetone. Compared with other hematite nanostructures, the porous hollow hematite spindles show outstanding performance in gas sensing due to their large surface area and porous hollow structure. Because of the unique porous hollow structures of the samples, the photocatalytic property of the spindle-like α-Fe2O3 was also investigated. 相似文献
994.
A novel synthesis of the functionalized bimodal mesoporous silica with ionic liquid (FBMMs) was performed. After grafting 1-methyl-3-(trimethoxysilyl)propylimidazolium chloride onto the surface of bimodal mesoporous silicas, 1,4-bis(9-O-quininyl)phthalazine ((QN)2-PHAL) and K2Os(OH)4·2H2O were immobilized onto the modified FBMMs by adsorption or ionic exchange methods, and then, the asymmetric dihydroxylation reaction was carried out by using solid catalysts. Techniques such as X-ray diffraction, Fourier Transform Infrared spectroscopy, N2 adsorption and desorption were employed to characterize their structure and properties. The results showed that the mesoporous ordering degree of bimodal mesoporous silica decreased after functionalization and immobilization of OsO4-(QN)2PHAL. Being very effective in asymmetric dihydroxylation with high yield and enantioselectivity, the prepared heterogeneous solid catalyst could be recycled for five times with little loss of enantioselectivity, with comparison of those results obtained in homophase system. Moreover, the effect of Osmium catalyst on asymmetric dihydroxylation was investigated. 相似文献
995.
Mathieu Herran Daniel Nélias Alain Combescure Hervé Chalons 《International journal for numerical methods in engineering》2011,86(3):301-315
The component mode synthesis (CMS) with fixed interface (denoted Craig–Bampton) method uses a combination of static and dynamic modes. The usual definition of this CMS leads to a coupling between static and dynamic modes which are not orthogonal with respect to the stiffness matrix. This type of basis is not well suited for dynamic explicit computations, because the resulting mass matrix is not diagonal. If one keeps the same basis mode set but uses an orthogonalization process with respect to the mass matrix, the quality of the reduced Craig–Bampton system is kept but the basis vectors are combined differently. The aim of this paper is to propose a new way to control the accuracy of the reduced dynamic system for a specific frequency domain. Thus a new CMS is defined in order to be accurate in the medium frequency range. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
996.
A simple and efficient activation process was conducted by deposition of palladium (Pd) nanoparticles on PMMA surface using a microwave-assisted polyol method with ethanol used as the reductant. The newly synthesized Pd nanoparticles were utilized as an activator for electroless nickel deposition. TEM images revealed that Pd nanoparticles of size 4-6 nm are formed evenly over the PMMA surface. A tight, smooth and continuous Ni plating layer was coated on these Pd nanoparticle activated PMMA microspheres. In contrast, a rough and discontinuous Ni film was obtained for the sample activated with a conventional sensitization/activation procedure. 相似文献
997.
Hexagonal ZnIn2S4 porous microspheres were synthesized via a cetylpyridinium bromide (CPBr)-assisted hydrothermal method. The structure, morphology and optical property of these prepared products were characterized by wide angle X-ray diffraction (WAXRD), small angle X-ray diffraction (SAXRD), UV-Vis diffusive reflectance spectroscopy (DRS), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analyzer (EDX) and nitrogen sorption analysis. The effects of CPBr and pH on the crystal structure, morphology and photocatalytic activity of ZnIn2S4 products were studied. The results demonstrated that the flowerlike ZnIn2S4 microspheres, which were composed of numerous nanosheets, performed higher visible-light photocatalytic activity than bulk ZnIn2S4 for hydrogen evolution. The CPBr addition influenced the crystal structure including the position and intensity of some peaks. Furthermore, the pH played a crucial role in the formation of ZnIn2S4 porous microspheres. The as-synthesized porous ZnIn2S4 microspheres possessed the specific surface area of 165.4 m2 g−1 and the slit-like porous configuration, which was beneficial to photocatalytic reaction. 相似文献
998.
Well dispersed Fe3O4 nanoparticles with mean size about 160 nm are synthesized by a simple chemical method at atmosphere pressure. The products are characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and Raman spectrum. Electrochemical properties of the as-synthesized Fe3O4 nanoparticles as anode electrodes of lithium ion batteries are studied by conventional charge/discharge tests, showing initial discharge and charge capacities of 1140 mAh g−1 and 1038 mAh g−1 at a current density of 0.1 mA cm−2. The charge and discharge capacities of Fe3O4 electrode decrease along with the increase of cycle number, arriving at minimum values near the 70th cycle. After that, the discharge and charge capacities of Fe3O4 electrode begin to increase along with the increase of cycle number, arriving at 791 and 799 mAh g−1 after 393 cycles. The morphology and size of the electrode after charge and discharge tests are characterized by SEM, which exhibits a large number of dispersive particles with mean size about 150 nm. 相似文献
999.
1000.