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Preparation of rod-like Aluminum Doped Zinc Oxide Powders by Sol-gel Technique Using Metal Chlorides and Acetylacetone Precursors

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS GARCIA Jorge Roberto GALAVIZ PEREZ Jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico Escuela Superior de Ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico Universidad Juárez Autònoma de Tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

Sine-Gordon Solitons and Breathers in rod-like Magnetic Liquid Crystals under External Magnetic Field

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Communications in Theoretical Physics 2018年第12期69卷 759-764页

作者：李妍鲁小波侯春风 Department of Physics Harbin Institute of Technology Department of Physics Science and Technology Heilongjiang University

To study the nonlinear phenomena in rod-like magnetic liquid crystals(RMLCs), this paper establishes the dynamic model of molecular motion when giving a twisting disturbance to the molecules under external magnetic field.We find the twist of the molecules under magnetic field can be propagated in the form of a traveling wave. The dynamic equation of the molecular twisting we derived satisfies the form of Sine-Gordon equation. We obtain two solutions of the Sine-Gordon equation by theoretical calculation: the kink and anti-kink solitons and breathers. The characteristics of those solitons and breathers are discussed.

关键词： rod-like magnetic liquid crystals Sine-Gordon equation kink and anti-kink solitons breathers

Formation and dispersal of rod-like α-SiAlON seed crystals synthesized by combustion method

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中国有色金属学会会刊：英文版 2005年第S3期15卷 439-442页

作者：傅仁利 J.M.F.Ferreira 杨克涛陈克新 College of Materials and Engineering Nanjing University of Aeroautics and Astroautics Nanjing 210016 China Department of Ceramics and Glass Engineering CICECO University of Aveiro 3810-193 Aveiro Portugal State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Beijing 100084 China

rod-like single-phase seed crystals of yttrium-α-SiAlONs were synthesized by combustion synthesis method. The XRD patterns, the morphologies of products and formation mechanism were investigated. The SEM observation of crystals exhibits well developed elongated hexagonal crystals with highly agglomerative features, assigned to pure and well-crystallized α-SiAlON. After special chemical treatments and water washing, the powders are well dispersed and still keep elongated hexagonal crystals, and the XRD pattern shows that the rod-like structure is crystalline yttrium-α-SiAlON with only a trace of β-SiAlON.

关键词： rod-like seed crystals Y-α-SiAlON combustion synthesis

1,4-DHP-lipid parameters and rod like micellae

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Journal of Biophysical Chemistry 2011年第4期2卷 386-394页

作者： Inta Liepina Cezary Czaplewski Adam Liwo Gunars Duburs Latvian Institute of Organic Synthesis Faculty of Chemistry University of Gdansk

The cationic amphiphilic lipid type compound 1,1’-{[3,5-bis(dodecyloxycarbonyl)-4-phenyl-1,4- dihydropyridin-2,6-diyl]dimethylene} bispyridinium dibromide (1,4-DHP lipid) (charge +2), is a gene transfection agent. The electronic structure of 1,4-DHP lipid molecule was investigated by ab initio quantum mechanics, the charges were derived, and the supramolecular structure formed by 1,4-DHP lipid molecules in water was investigated by means of molecular dynamics simulation, f99 force field, version AMBER 8.0. During the molecular dynamics simulations of 10 ns of MD 1,4-DHP lipid formed a worm-like micellae, which was preserved during the time course of 300 ns of MD simulations. Result was confirmed with the electron microscopy showing extended, rod-like structures as one of the 1,4-DHP lipid supramolecular structures, which are expected to be formed at high 1,4-DHP lipid concentrations.

关键词： Lipid Gene Transfection rod-like Structure Worm-like Micellae Tubular Micellae Molecular Dynamics

Synthesis and Luminescence Properties of(Y, Gd)(P, V)O_4:Eu^(3+), Bi^(3+) Red Nano-phosphors with Enhanced Photoluminescence by Bi^(3+), Gd^(3+) Doping

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Nano-Micro Letters 2013年第2期5卷 117-123页

作者： Yong Pu Ke Tang Da-Chuan Zhu Tao Han Cong Zhao Ling-Ling Peng College of Material Science and Engineering Sichuan University College of Information Engineering Chengdu University of Technology Chongqing Key Laboratory of Micro/Nano Materials Engineering and Technology

A series of(Y_(1-y), Gdy)_(0.95-x)(P_y, V_(1-y))O_4 :0.05Eu^(3+), xBi^(3+)+phosphors have been successfully prepared by a subsection method. The crystal structure, surface morphology and luminescence properties were investigated. It was found that the sintered samples crystallized in a tetragonal crystal system with space group I_(41)/amd(a = b = 0.7119 nm, c = 0.6290 nm). The products presented rod-like morphology with length of 100-150 nm and width of 50-100 nm. A maximum peak at 619 nm(~5D_0 →~7F_2) was observed in emission spectrum of the phosphors. It was also found that co-doping of Bi^(3+)+, P5+and Gd^(3+)ions into YVO_4:Eu^(3+)can not only made the right edge of the excitation band shift to the long-wavelength region, but also increased the emission intensity at 619 nm sharply and decreased the lifetime of fluorescence decay. These results may expand the application scope of the phosphors.

关键词： (Y,Gd)(P,V)O4:Eu3+,Bi3+ rod-like Red phosphors Photoluminescence Doping

Study of Photocatalytic Degradation of Methyl Orange on Different Morphologies of ZnO Catalysts

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Modern Research in Catalysis 2013年第2期2卷 19-24页

作者： Chih-Wei Tang Department of General Education Army Academy Taoyuan Chinese Taipei

In this study, several ZnO catalysts were prepared using different zinc sources as precursors. The different catalyst mor- phologies obtained were used to degrade photocatalytically a methyl orange (MO) dye solution, which was used to model wastewater pollution. The precursors, Zn(CH3COO)2, ZnCl2 and Zn(NO3)2, were individually added to a solution containing cetyltrimethylammonium bromide (CTAB) and sodium hydroxide (NaOH) for the hydrothermal synthesis of ZnO. After the hydrothermal reaction, the samples of ZnO were filtered, washed, dried at 110?C and calcined at 550?C, resulting in the formation of the rod-like (designated ZnO(I)), the rice-like (designated ZnO(II)) and the granular-like (designated ZnO(III)) catalysts. The catalysts were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM) and their UV-visible diffuse reflectance spectra (UV-Vis DRS). The results indicate that the photocatalytic degradation of the MO solution, after 60 min of UV irradiation, can reach percentages of 40%, 96% and 99% using the catalysts ZnO(I), ZnO(II) and ZnO(III), respectively. The morphology of the ZnO catalyst had an ap- parent effect on the rate of the photocatalytic degradation of MO. The ZnO(II) and ZnO(III) catalysts have higher S/V ratios and a greater content of oxygen vacancies, resulting in different absorbances of ultraviolet light, which leads to different rates of photocatalytic degradation of MO.

关键词： ZnO Morphology Hydrothermal rod-like Rice-like Granular-like