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731.
This paper is concerned with nonlocal Kirchhoff?s equation
732.
A novel 3D polymer 1 (C26H22CoN4O4, Mr = 513.41) constructed from H2C4BIm (2,2'-(1,4-butanediyl)bis(1H-benzimidazole)], 1,3-bdc (1,3-benzenedicarboxylate) and Co(II) has been successfully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analysis. The crystal belongs to the tetragonal system, space group I-42d with a = 24.315(5), b = 24.315(5), c = 8.343(2), V = 4933(2)3, Z = 8, Dc = 1.383 g/cm3, μ(MoKα) = 0.735 mm-1, F(000) = 2120, S = 1.156, the final R = 0.0596 and wR = 0.1346 for 1529 reflections with I > 2σ(I). Complex 1 contains 1D chains which are connected by extensive hydrogen-bonding interactions to form the 2D folded layer and 3D framework, which also stabilize the structure. 相似文献
733.
Wanting Sun Mingzheng Xie Liqiang Jing Yunbo Luan Honggang Fu 《Journal of solid state chemistry》2011,184(11):3050-3054
In this work, monoclinic scheelite-type BiVO4 nanoparticle with large surface area has been successfully synthesized, using Bi(NO3)3 and NH4VO3 as raw materials, through a hydrothermal process in the presence of ethylene diamine tetraacetic acid (EDTA). It is demonstrated that the nanoparticle size of as-prepared BiVO4 becomes small by decreasing hydrothermal temperature, shortening hydrothermal reaction time and increasing EDTA amount used. The resulting BiVO4 nanoparticle with large surface area exhibits a good photocatalytic performance for degrading phenol solution as a model organic pollutant under visible illumination. The key of this method is the chelating role of EDTA group in the synthetic process that it can greatly control the concentration of Bi3+, leading to the growth inhibition of BiVO4 crystallite. The work provides a route for the synthesis of Bi-containing nano-sized composite oxides with large surface area. 相似文献
734.
Ga2O3:In films with different indium (In) content x [x=In/(Ga+In) atomic ratio] have been deposited on MgO (1 0 0) substrates by metalorganic chemical vapor deposition (MOCVD). Structural analyses revealed that the film deposited with actual In content (x′) of 0.09 was an epitaxial film and the films with x′=0.18 and 0.37 had mixed-phase structures of monoclinic Ga2O3 and bixbyite In2O3. The absolute average transmittance of the obtained films in the visible region exceeded 95%, and the band gap was in the range of 4.74-4.87 eV. Photoluminescence (PL) measurements were performed at room temperature, in which the visible luminescences were strong and could be seen by the naked eye. The strong emissions in the visible light region were proposed to originate from the gallium vacancies, oxygen deficiencies and other defects in these films. 相似文献
735.
736.
Han P Luan F Gao Y Wang J Liu H 《Combinatorial chemistry & high throughput screening》2011,14(7):601-615
A linear quantitative structure-visible light absorption wavelength (λ) relationship model for one hundred and forty-two photosensitizers was proposed using heuristic method and multiple linear regression analysis. The statistical parameters of the model were R2 = 0.916; F = 372.16; and RMSE = 5.0873. A fivefold cross-validation algorithm was applied, and the results indicated that the model has a satisfactory statistical stability and validity. The proposed model was evaluated for predictive ability with an external validation set, and the statistical parameters obtained were and R2EXT = 0.908; Q2EXT = 0.897; F = 118.14; and RMSEEXT = 5.6338 for the external test set. The results obtained demonstrated that the simple linear quantitative structure-wavelength relationship model was robust and satisfactory. It could be a feasible and effective tool for predicting λ of photosensitizers, which is an important parameter for their effect on photodynamic therapy for cancer, and could be a potential way for instructing synthesis of this kind of new photosensitizers. 相似文献
737.
Structure and photoluminescence properties of epitaxial SnO2 films grown on α-Al2O3 (0 1 2) by MOCVD
SnO2 thin films have been successfully deposited on α-Al2O3 (0 1 2) substrates by metalorganic chemical vapor deposition (MOCVD) in the temperature range 500-700 °C. The films were epitaxially grown in the tetragonal SnO2 phase and were (1 0 1) oriented. In-plane orientation relationship [0 1 0]SnO2||[1 0 0]Al2O3 and [1 0 1?]SnO2||[1? 2? 1]Al2O3 was determined between the film and substrate. Photoluminescence (PL) spectra measured at room temperature revealed that the film grown at 700 °C showed an intense ultra-violet (UV) PL peak at 333 nm, which was a band-edge emission peak in SnO2 films. At a temperature of 13 K, a new broad PL band centered at about 480 nm was observed. The corresponding PL mechanisms are discussed in detail. 相似文献
738.
A novel fiber design of large mode area (LMA) all-glass leakage channel fibers (LCF) with triangular core is proposed. The effective single mode behavior and bend characteristics of the fiber are numerically investigated. The designed LCFs can achieve LMA larger than 1400 μm2, effective single mode operation and low bend loss by carefully choosing the diameters of the fluorine-doped silica rods. 相似文献
739.
Luan L Lippman TM Hicks CW Bert JA Auslaender OM Chu JH Analytis JG Fisher IR Moler KA 《Physical review letters》2011,106(6):067001
We measure the penetration depth λab(T) in Ba(Fe(1-x)Co(x))(2)As(2) using local techniques that do not average over the sample. The superfluid density ρs(T) ≡ 1/λab(T)2 has three main features. First, ρs (T = 0) falls sharply on the underdoped side of the dome. Second, λab(T) is flat at low T at optimal doping, indicating fully gapped superconductivity, but varies more strongly in underdoped and overdoped samples, consistent with either a power law or a small second gap. Third, ρs (T) varies steeply near Tc for optimal and underdoping. These observations are consistent with an interplay between magnetic and superconducting phases. 相似文献
740.
Coatings with a thickness of 22-32 μm were formed on an AM60B magnesium alloy by plasma electrolytic oxidation (PEO) in electrolytes containing 12.0-24.0 g/l NaAlO2 and other additives. SEM analyses of the coated samples showed that the coatings were compact with relatively low porosity. X-ray diffraction revealed that the coatings consisted of mainly MgAl2O4 and MgO phases. The relative amount of MgAl2O4 in the coating increased with increasing NaAlO2 concentration. The relatively compact and thick coatings provide good corrosion protection for magnesium, as indicated by the results of potentiodynamic polarization tests. In addition, the PEO treatment also significantly improved the wear resistance of the alloy. Pin-on-disk wear tests showed that the PEO treatment reduced the wear volume loss by a factor of 10. 相似文献