886 resultados para dextran coating


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A kind of 1,6,10,15,19,24,28,33-octa-iso-pentyloxy-2,3-metallonaphthalocyanines complexes MNc(iso-PeO)(8) (M = Co, Cu, Pd) are used as spincoating film-forming materials. The surface morphologies of the films prepared were studied first. These films were then used for the experiments of NO2 sensing. The effects of sensing temperature as well as the NO concentration on the sensing properties were studied. The experimental results showed that the three MNc(iso-PeO)(8) films were uniform, smooth and dense. Due to the different metal ions (M) on the center of naphthalocyanine, the CoNc(iso-PeO)(8) film had a higher film resistance and response-recovery rate in the NO2 sensing experiments. On the contrary, the response to NO2 of the PdNc(iso-PeO)(8) and CuNc(iso-PeO)(8) films were superior to that of CoNc(iso-PeO)(8). By varying the sensing temperature, it was found that the elevation of sensing temperature could improve the sensing response, recovery ratio, and sensitivity of the sensing films. At high concentrations of NO2, the response time became shorter. (c) 2007 Elsevier B.V. All rights reserved.

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Smooth thin films of three kinds of nickel(II)-azo complexes were prepared by the spin-coating method. Absorption spectra of the thin films on K9 glass substrate in the 300-600 nn wavelength region were measured. Optical constants (complex refractive index N = n + ik) and thickness of the thin films prepared on single-crystal silicon substrate in the 300-600 nm wavelength region were investigated on rotating analyzer-polarizer type of scanning ellipsometer, and dielectric constants epsilon (epsilon = epsilon(1) + i epsilon(2)), absorption coefficients a as well as reflectance R of thin films were then calculated at 405 nm. In addition, in order to examine the possible use of nickel(II)-azo complex thin film as an optical recording medium, one of the nickel(II)-azo complex thin film prepared on K9 glass substrate with an Ag reflective layer was also studied by atomic force microscopy and static optical recording. The results show that the nickel(II)-azo complex thin film is smooth and has a root mean square surface roughness of 2.25 nm, and the recording marks on the nickel(II)-azo complex thin film are very clear and circular, and their size can reach 200 nn or less. (c) 2006 Elsevier Ltd. All rights reserved.

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Two kinds of nickel(II) and copper(II) P-diketone complexes derived from thenoyltrifluoroacetone ligand with blue-violet light absorption were synthesized by reacting free ligand and different metal(II) ions in sodium methoxide solution. Their structures were postulated based on elemental analysis, ESI-MS, FT-IR spectra and UV-vis electronic absorption spectra. Smooth films on K9 glass substrates were prepared using the spin-coating method. Their solubility in organic solvents, absorption properties of thin film and thermal stability of these complexes were evaluated. (c) 2006 Elsevier B.V. All rights reserved.

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A new chelating ligand, 2-(2-(5-tert-butylisoxazol-3-yl)hydrazono)-N-(2,4-dimethylphenyl)-3-oxobutanamide (HL), and its four binuclear transition metal complexes, M-2(L)(2) (mu-OCH3)(2) [M = Ni(II), Co(II), Cu(II), Zn(II)], were synthesized using the procedure of diazotization, coupling and metallization. Their structures were postulated based on elemental analysis, H-1 NMR, MALDI-MS, FT-IR spectra and UV-vis electronic absorption spectra. Smooth films of these complexes on K9 glass substrates were prepared using the spin-coating method and their absorption properties were evaluated. The thermal properties of the metal(II) complexes were investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC. Different thermodynamic and kinetic parameters namely activation energy (E

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合成了2-(2-氨基-6-乙氧基苯并噻唑基偶氮)-5-(N,N-二乙基氨基)三氟甲基磺酰苯胺偶氮染料(EBTDATFS)及其与乙酸镍、乙酸钴、乙酸铜、乙酸锌等金属盐鏊合的金属鏊合物。通过红外光谱、紫外-可见吸收光谱和MALDI质谱等对染料及其金属鏊合物进行了结构表征;使用旋涂方法在K9玻璃和抛光的单晶硅基片上制备薄膜;研究了镍金属鏊合物的热学性能;使用椭偏仪研究了Ni和Zn鏊合物的光学常数。结果表明:4种金属鏊合物薄膜最大吸收光谱为621-629nm,且长波边吸收峰陡峭;TGA-DSC测试结果表明镍金属鏊

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Three kinds of rare earth complexes derived from dibenzoylmethane (DBM) ligand were synthesized by reacting free ligand and different rare earth ions(La (3+), Sm3+ and Gd3+). Their contents and structures were postulated based on elemental analysis, LDI-TOF-MS, FT-IR spectra and UV-Vis spectra. Smooth films on K9 glass substrates were prepared using the spin-coating method. Their solubility in organic solvents, absorption and reflection properties of thin film and thermal stability of these complexes were evaluated. These complexes would be a promising recording material for high-density digital versatile disc-recordable (HD-DVD-R) system. (c) 2007 Elsevier B.V. All rights reserved.

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Two new hydrazone chelating ligands, 2-(2-(5-methylisoxazol-3-yl)hydrazono)-5,5-dimethylcyclohexane-1,3-dione (HL1) and 2-(2-(5-tert-butylisoxazol-3-yl)hydrazono)-5,5-dimethylcyclohexane- 1,3-dione (HL2), and their nickel(II) and copper(II) complexes were synthesized using the procedure of diazotization, coupling and metallization. Their structures were postulated based on elemental analysis, H-1 NMR, ESI-MS, FT-IR spectra and UV-vis electronic absorption spectra. Smooth films of these complexes on K9 glass substrates were prepared using spin-coating and their absorption properties were evaluated. The thermal properties of the metal(II) complexes were investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). Different thermodynamic and kinetic parameters namely activation energy (E

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针对非合作小目标激光测距系统,目标表面的反射特征对激光回波信号有很大的影响。建立测量表面双向反射分布函数(BRDF)的装置,对常用的两种热控材料——白漆涂层和F36多包层,测量了其在1064 nm波长下的双向反射分布函数。得出了白漆涂层镜面反射很小,散射角较大,利于各方向接收回波信号;而F36多包层镜面反射很强,散射角-2°~2°,不利于探测。通过由表面BRDF与由朗伯散射计算得到的最小接收功率的比较,得出了入射角大于45°入射白漆涂层时,回波信号较小;大于2°入射F36多包层时,没有回波信号。

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Nesta dissertação são apresentados resultados de simulações Monte Carlo de fluorescência de raios X (XRF), utilizando o programa GEANT4, para medidas de espessura de revestimento metálico (Ni e Zn) em base metálica (Fe). As simulações foram feitas para dois tamanhos de espessura para cada metal de revestimento, (5μm e 10μm), com passos de 0,1 μm e 0,001 μm e com 106 histórias. No cálculo da espessura do revestimento foram feitas as aproximações de feixe de raios X monoenegético, com a análise da transmissão apenas da energia do K-alfa e para uma geometria compatível com um sistema real de medição (ARTAX-200). Os resultados mostraram a eficiência da metodologia de simulação e do cálculo da espessura do revestimento, o que permitirá futuros cálculos, inclusive para multirevestimentos metálicos em base metálica.

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The LB films and spin-coated films of tetra-neopentoxy phthalocyanine zinc (TNPPcZn) were prepared and annealed at different temperatures. Their refractive index (n) and extinction coefficient (k) were measured by p-polarized reflectance. The similar value of n and k, as well as similar changing tendency of it and k at varied annealing temperatures, was found between LB films and spin-coated films. In addition, the absorption curves of TNPPcZn LB films and spin-coated films in visible range at different annealing temperature were investigated. The results indicate that the changing tendency of the extinction coefficient of two kinds of TNPPcZn films obtained from two methods mentioned above were coincident. When the annealing temperature increased to 150 degrees C, the monomers of TNPPcZn films transformed to aggregates, n(f) and k(f) of the films increased. Further, n(f) and k(f) decreased as aggregates changed back to monomers again at the annealing temperature of 300 degrees C. The experimental results coincide well with the theoretical analysis. (C) 2004 Elsevier B.V. All rights reserved.

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Two kinds of silanes, 3-glycidoxypropyltrimethoxysilane (GLYMO) and 3-trimethoxysililpropylmethacrylate (TMSPM), were used to prepare ormosil waveguide films by the sol-gel method. Thirty percent Ti(OBu)(4) and 70% silane were contained in the precursor sets. The properties of films were measured by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV/VIS/NIR spectrophotometer (UV-vis), atomic force microscopy (AFM), m-line and scattering-detection method. The films from GLYMO and TMSPM precursors exhibit similar thickness (2.58 mu m for GLYMO, 2.51 mu m for TMSPM) and refractive index (1.5438 for GLYMO, 1.5392 for TMSPM, lambda=632.8 nm), but the film from TMSPM precursor has higher propagation loss (1.024 dB/cm, lambda=632.8 nm) than the film prepared from GLYMO (0.569 dB/cm, lambda=632.8 nm). Furthermore, the film prepared from TMSPM is easy to be opaque and cracks during coating whereas the same phenomenon was not found for the film prepared with GLYMO. It is confirmed that GLYMO is a better precursor than TMSPM for waveguide film preparation. (C) 2005 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

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成功制备了高质量的Nd:YAG透明陶瓷,激光测试样品的尺寸为3mm×3mm×3mm,双面抛光、未镀膜,最高连续输出能量为1003mW,斜率效率为14%.

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水热法生长了复合钛宝石(Al2O3/Ti:Al2O3)激光晶体.对外层Al2O3X射线ω扫描表明其晶体质量很高.外层生长的Al2O3和内部的钛宝石激光棒结合牢固、紧密,因而能适应高强度泵浦所带来的激光介质内部的热应力.复合激光晶体界面层带来的光损耗很小.就我们所知,这是首次用水热法生长复合激光晶体.

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在预先镀有ZnO纳米层的(0001)蓝宝石衬底上利用低温水热法制备出ZnO薄膜。SEM和XRD显示此ZnO膜是由六棱柱状阵列构成的,基于蓝宝石衬底生长,具有高度的c轴择优取向,且(0004)摇摆曲线的FWHM达到1.8°。并发现了在水热溶液中加入一定量六次甲基四胺可以调节六棱柱状ZnO尺寸比例。

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Well-aligned ZnO films have been successfully prepared by using low-temperature hydrothermal approach on (0001) sapphire substrates that were pre-coated with a ZnO nano-layer by dip-coating. The characterizations of scanning electron microscopy (SEM) and X-ray diffraction (XRD) indicate that the ZnO films consist of hexagonal rods that grow along the c axis based on the sapphire substrates. It is found that the size of ZnO rods can be adjusted by an aqueous solution with some methenamine. (c) 2006 Elsevier B.V. All rights reserved.