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991.
992.
Minju Ying Yueyuan Xia Yuming Sun Yuchen Ma Mingwen Zhao Xiaotao Hao Xiangdong Liu 《Optics & Laser Technology》2003,35(6):475-480
Optical emission spectra of Nd:YAG laser ablation of KTiOPO4 (KTP) crystal and SnO2:Sb transparent conducting thin film were recorded and analyzed in vacuum and in air. The integral intensities of spectral lines from laser-ablated KTP crystal were obtained as functions of distance from the target surface and laser power density in vacuum and in air. The ambient gas effects on pulsed laser ablation of target were discussed. We also performed laser ablation of SnO2:Sb transparent conducting thin film in air and the electron temperature and full-width at half-maximum (FWHM) of atomic and ionic spectral lines in the plasma were quantified using Boltzmann plot method and Lorentzian fit, respectively. Integral intensities of atomic and ionic Sn spectral lines were also obtained as functions of distance from the target surface and laser irradiance. The intensity ratio of ionic and atomic Sn spectral lines as a function of laser power density was got which gives some information about the variation of ionization ratio with laser irradiance in the plasma produced by high-power laser. 相似文献
993.
A. L. Thomann A. Basillais M. Wegscheider C. Boulmer-Leborgne A. Pereira P. Delaporte M. Sentis T. Sauvage 《Applied Surface Science》2004,230(1-4):350-363
This study focuses on the chemical, morphological and structural characterization of iron surfaces treated by laser in ambient air. Incorporation of nitrogen over a 1–2 μm thickness (10–30 at.% at the profile maximum) and superficial oxidation on 200–400 nm depth have been evidenced by nuclear reaction analyses. X-ray diffraction at grazing incidence has shown the formation of FeO and Fe3O4 oxide phases as well as γ-Fe(N), and ε-FexN for a sufficiently high amount of nitrogen incorporated. Treatments performed with different laser beams indicate that the parameter playing the major role in surface modification processes is the wavelength. Nitrogen incorporation has been found to occur via the interaction of reactive N, present in the laser-induced plasma, and the iron molten bath. The nitriding process is promoted in the IR wavelength range. Oxidation takes place by chemical reaction during the cooling step, and is furthered in the case of UV treatment. 相似文献
994.
以1 030 nm高反,940,980 nm高透的波长分离膜作为实例,为提高该薄膜元件的波长分离效果,从膜系的优化方面做了一系列的研究,诸如采用带通滤光片的设计思想,在膜堆两侧加入了匹配层,调整膜堆的周期厚度,并用膜系设计软件对通带作进一步的优化.通过这一系列的优化设计后,利用RF双离子束溅射工艺在BK7玻璃基底上沉积样品薄膜,并在基底背面加镀通带增透膜.结果显示,透射带在940和980 nm处的透过率分别为97.73%和93.63%,反射带在1 030 nm的反射率为99.99%.对所制备的样品薄膜进行了激光损伤阈值测量,得到了35 J/cm2(1 064 nm,12 ns)的结果. 相似文献
995.
996.
稀土在激光熔覆涂层中的分布和行为 总被引:23,自引:2,他引:23
用激光快速熔凝法研究了加入钢表层稀土的行为和分布。结果表明,因用激光处理含稀土的涂层能够使较多的稀土偏聚到钢的表层;偏聚到钢表层的过饱和稀土除与氧、硫作用外,还可固溶于晶内、晶界或晶界附近,甚至能形成金属间化合物RE2Fe17;经过激光处理后表面稀土的作用更为明显 相似文献
997.
《Electrophoresis》2018,39(17):2246-2252
Upconversion nanoparticles (UCNPs) are an emerging class of optical materials with high potential in bioimaging due to practically no background signal and high penetration depth. Their excellent optical properties and easy surface functionalization make them perfect for conjugation with targeting ligands. In this work, capillary electrophoretic (CE) method with laser‐induced fluorescence detection was used to investigate the behavior of carboxyl‐silica‐coated UCNPs. Folic acid, targeting folate receptor overexpressed by wide variety of cancer cells, was used for illustrative purposes and assessed by CE under optimized conditions. Peptide‐mediated bioconjugation of antibodies to UCNPs was also investigated. Despite the numerous advantages of CE, this is the first time that CE was employed for characterization of UCNPs and their bioconjugates. The separation conditions were optimized including the background electrolyte concentration and pH. The optimized electrolyte was 20 mM borate buffer with pH 8. 相似文献
998.
A laser processed micro-supercapacitor (LPMS) based on carbon nanotubes/manganese dioxide composite is fabricated through slurry dispensing and laser scribing techniques. This device presents superior electrochemical performance and aesthetic property. 相似文献
999.
A simple method utilizing laser writing technology to fabricate all-solid-state micro-supercapacitors was reported. The solid-state micro-supercapacitors based on MnO2/graphene nanocomposites deliver high volumetric capacitances, promising energy density, good stability and low leakage current. 相似文献
1000.
Gadolinium oxide - Graphene (Gd2O3-G) nanocomposites were prepared with different weight ratio of graphene using low temperature solution process. The structural, morphological, electrochemical and photocatalytic properties of the composites were investigated by X-ray diffraction, Raman, FE-SEM, HRTEM, Cyclic voltammetric and photo-degradation analysis. The chemical composition of the composites was studied by elemental mapping analysis using EPMA. The binding states of various elements present in the composites were analyzed by XPS. Cyclic voltammetric studies revealed that the nanocomposite with 5% graphene exhibits the specific capacitance of 26 F g−1, which is higher than that of pure Gd2O3 (18 F g−1). The presence of graphene has greatly enhanced the photocatalytic performance of Gd2O3G composites as the rate of degradation of MB dye is relatively higher in the composites compared to pure Gd2O3. The significant increase in the specific capacitance and rate of degradation of dye suggest that the Gd2O3G is a promising material for energy storage and environmental applications. 相似文献