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101.
102.
We report our results on effective third-harmonic generation (THG) by cascading quasi-phase-matched second-harmonic and sum-frequency generation in a dual-period-periodically-poled KTP crystal. Significant improvement of the output powers were achieved for the 440 nm blue light and 660 nm red light based on Q-switched frequency-tripling and frequency-doubling 1319-nm radiation inside an adhesive-free bond composite Nd:YAG laser. The highest output powers of 197 mW and 1.19 W were achieved for the blue and red light at the corresponding input powers of 12.9 and 17.1 W for the diode laser. 相似文献
103.
We demonstrate the coherent beam combination of eight Watt-level polarization-maintained fiber amplifiers. The phase control signal of each amplifier is generated by running a stochastic parallel gradient descent algorithm on a digital signal processor (DSP). The experimental result shows that the whole system in close-loop performs well for long-time observation. Energy encircled in the target pinhole is 6.68 times more than that in open-loop. The combination efficiency is as high as 84.5%. 相似文献
104.
Gary Shambat Albert Deberardinis Petra Reinke Lin Pu John Bean 《Applied Surface Science》2009,255(20):8533-8538
Studies were performed to determine the chemical addition of a metal complex molecule, chlorotris(triphenylphosphine)iridium(I), on hydrogen passivated Si(1 1 1) surfaces to form a self-assembled monolayer (SAM). The iridium complex was synthesized prior to chemical addition, for which modified reaction conditions were chosen. Following addition, the silicon surfaces were characterized with X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). The XPS results revealed that the surfaces consisted of the expected elemental percentages and that the iridium has a slightly higher success rate at attaching to oxide-free surfaces. XPS data also strongly indicate that the iridium complex remained intact upon chemisorption and did not decompose during the addition reaction. CV data show a difference between iridium treated surfaces and control samples. Hydrogen passivated wafers with iridium complex were much more conductive than those which were terminated with just an oxide or with an oxide and iridium complex. Furthermore, no free iridium reagent was detected as an additional feature in the current profile, indicating there was no physisorbed layer. 相似文献
105.
Jibin Pu Xiufang Liu Liping Wang Qunji Xue 《Surface and interface analysis : SIA》2011,43(10):1332-1340
Several single‐component and two‐component imidazolium ionic liquids (ILs) ultrathin films were formed on Si substrates by a dip‐coating and heat treatment process. The formation and surface properties of the films were analyzed by means of ellipsometric thickness measurement, X‐ray photoelectron spectra and atomic force microscope. The adhesive and nanotribological behaviors of the films were evaluated by a homemade colloidal probe. A ball‐on‐plate tribometer was used to test the microtribological performances of these films. As a result, the two‐component ILs ultrathin film containing 80% solid‐like ILs phase shows more homogenous surface morphologies and optimal micro/nano‐tribological properties as compared to single‐component ILs films, which is ascribed to a synergic effect between the steady solid‐like ILs phase as the backbone and the proper amount of flowable liquid‐like ILs phase. By studying the influence of various solid/liquid ILs ratios on tribological properties of the two‐component ILs films, we might find the way to design ILs films with excellent comprehensive tribological properties. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
106.
建立了电视机外壳样品中10种多溴二苯醚的微波萃取-气质联用测定方法。10种多溴二苯醚的定量峰面积与其浓度在一定范围内成线性关系,检出限从0.08μg/m L到0.60μg/m L。采用索氏萃取法进行方法验证,测试结果的RSD≤2.83,两种方法经t检验无显著性差异。该方法具有简便、快速、试剂消耗量少的优点,可应用于电视机等国推污染控制认证产品塑料材料中多溴二苯醚测定。 相似文献
107.
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109.
Liangru Yang Yunfei Li Pu Mao Jinwei Yuan Yongmei Xiao 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):780-788
AbstractThe catalytic activity of a series of chiral heteroaryl coordinated chelating N-heterocyclic carbene (NHC) palladium complexes towards asymmetric allylic alkylation (AAA) were presented here. The effects of different N-substituents, NHC backbones and chelate rings on the catalytic activity and the enantioselectivity of the alkylation of (E)-1,3-diarylallyl acetates with dialkyl malonate were investigated. The results showed that, under the optimized conditions, complexes 3a, 3b, and 3i carrying the pyridinyl-coordinated five-membered chelate ring showed high catalytic activity and chiral induction efficiency. The corresponding alkylated products were obtained in high yields with moderate ee. Furthermore, it was found that the substituents of (E)-1,3-diarylallyl acetates and the type of the nucleophile affect the results as well. 相似文献
110.
Guang-Feng Hong Zhen-Hua Dong Yong-Mei Xiao Pu Mao Ling-Bo Qu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):771-779
AbstractA practical metal-free procedure for the synthesis of (E)-vinyl sulfones has been developed through the coupling of β-nitrostyrenes with sodium sulfinates under microwave irradiation. This methodology provides a convenient and efficient approach to various (E)-vinyl sulfones from readily available starting materials with excellent regioselectivity. The present oxidative reaction involves an efficient denitrative radical cross-coupling of β-nitrostyrenes with sodium sulfinates via using AcOH as an additive. 相似文献