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Ion-Beam Bombarding Effects on Deposition of Carbon Nitride Films by Laser Ablation

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Chinese Physics Letters 1996年第11期13卷 878-880页

作者： YING Zhi-feng ren Zhong-min DU Yuan-cheng LI Fu-ming LIN Jing ren yun-zhu ZONG Xiang-fu Department of Physics and State Key Lab oratory for Materials Modification by LaserIon and Electron beamsFudan UniversityShanghai 200433 Institute of Materials Science Fudan UniversityShanghai 200433

In order to obtain high quality carbon nitride films,x-ray photoelectron spectroscopy and Raman spectrum were used to analyze several kinds of film:(a)laser-ablated amorphous carbon(a-C)films,(b)a-C films after a 1 keV nitrbgen ion beam bombardment.(c)carbon nitride(CN_(x))films synthesized by ablation assisted with ion beam bombardment,(d)CN_(x) films after a 50eV nitrogen ion beam bombardment,and(e)CN_(x) films after a 1 keV nitrogen ion beam *** comparison among these films showed that the concurrent deposition of CN_(x) films by ablation and a nitrogen ion beam should be better than the post-treatment of a-C films by nitrogen ion beam *** the case of concurrent deposited CN_(x) films,a post-treatment by a nitrogen ion beam bombardment with an appropriate energy(possibly less than 1 keV)was proposed to improve the ratio of C-N binding structures in the deposited films.

关键词： beam films amorphous

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社会化医疗保洁的调查与分析

中华医院感染学杂志 2011年第12期21卷 2510-2511页

作者：汪素珍陆杏仁任云珠余姚市人民医院妇产科浙江余姚315400

目的了解目前医疗保洁社会化后的环境卫生状况,探索提高医疗保洁管理质量的方法和措施。方法采用自行设计的调查表,以现场调查、访谈等方法进行调查分析。结果保洁公司对医院感染管理的专业知识缺乏了解,对保洁的用物清洗消毒不规范,拖... 详细信息

目的了解目前医疗保洁社会化后的环境卫生状况,探索提高医疗保洁管理质量的方法和措施。方法采用自行设计的调查表,以现场调查、访谈等方法进行调查分析。结果保洁公司对医院感染管理的专业知识缺乏了解,对保洁的用物清洗消毒不规范,拖把、尘推、抹布随意清洗和放置,极易造成污染和交叉感染。结论医疗保洁迫切需要建立行业标准,规范清洁消毒的工艺流程和保洁用物的消毒方法。

关键词：医院保洁感染管理

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双十字轴万向节传动力学建模与仿真

上海交通大学学报 2004年第11期38卷 1922-1927页

作者：任少云朱正礼张建武上海交通大学机械与动力工程学院上海200030

通过对典型双十字轴万向节传动空间运动约束分析,分别建立了万向节传动系统运动学和动力学模型;利用数值仿真分析软件,观察到万向节传动运动存在简谐特性,在车辆加速工况和准静态工况下,万向节传动支反力也存在周期简谐特性.分析得到的... 详细信息

通过对典型双十字轴万向节传动空间运动约束分析,分别建立了万向节传动系统运动学和动力学模型;利用数值仿真分析软件,观察到万向节传动运动存在简谐特性,在车辆加速工况和准静态工况下,万向节传动支反力也存在周期简谐特性.分析得到的结论与传统矢量分析方法的结论相吻合;文中的建模和仿真分析方法为传统件结构的疲劳设计和失效分析提供了理论定量分析依据;对车辆中其他型式的万向节传动设计和研究具有参考价值.

关键词：双十字轴万向节运动铰主约束方程动力学建模

GPU加速条件下基于相位补偿反投影算法的太赫兹ISAR成像

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红外与毫米波学报 2022年第2期41卷 448-456页

作者：梁美彦任竹云李光辉张存林 Aly.E.Fathy 山西大学物理电子工程学院山西太原030006 首都师范大学物理系北京100048 田纳西大学电气工程与计算机科学系美国诺克斯维尔37996-2250

介绍了0.22 THz步进频率雷达系统及二维高分辨率ISAR成像方法。该雷达系统的合成带宽为12GHz,可以同时实现近场及远场成像。在近场条件下,该系统在距离向和方位向实现二维高精度成像,通过相位补偿反投影算法,太赫兹ISAR图像的分辨率可... 详细信息

介绍了0.22 THz步进频率雷达系统及二维高分辨率ISAR成像方法。该雷达系统的合成带宽为12GHz,可以同时实现近场及远场成像。在近场条件下,该系统在距离向和方位向实现二维高精度成像,通过相位补偿反投影算法,太赫兹ISAR图像的分辨率可以达到厘米量级。研究结果表明,采用同样的太赫兹频率步进雷达系统,基于反投影算法的太赫兹ISAR成像可以实现更高的精度和更精细的分辨率。为了加速成像过程,采用了GPU的加速平台,该方法为进一步开展近场高分辨率雷达成像,特别是太赫兹波段雷达成像提供了研究基础。

关键词：太赫兹 ISAR成像 BP算法高分辨率

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： Qing-yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词：

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Study on HOBEM Based on Analytical Panel Integrals Related to Translating-Pulsating Source for Hydrodynamic Responses of Vessels Sailing in Waves

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China Ocean Engineering 2022年第3期36卷 348-362页

作者： YANG yun-tao zhu ren-chuan LI Yu-long School of Naval Architecture and Civil Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China State Key Laboratory of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Technology Centre for Offshore and Marine Singapore(TCOMS)Singapore

A higher-order boundary element method(HOBEM)incorporated with analytical panel integrals related to translat-ing-pulsating source Green’s function is proposed for the hydrodynamic response prediction of ships advancing in *** this method,the 9-node bi-quadratic curvilinear elements employed to discretize the mixed-source/dipole boundary integral equation are mapped into the parametric plane through a coordinate *** in order to ease the numerical instability problem,a novel analytical quadrature is derived to calculate the influence coefficients by changing the integral order and using integration by *** singularity caused by infinite discontinuity is analyzed and eliminated by adopting some mathematical *** the calculations of panel integrals of Green’s function and its x-derivative,the analytical integral method is proved to be always accurate even for field points approaching the free surface,where numerical quadrature is impossible to give reasonable *** on this,a higher-order seakeeping program is developed and applied in the motion response prediction of two different types of ships(i.e.,a wall-sided ship Wigley III and a non-wall-sided ship S175).By comparing the computed results with the corresponding experimental data and numerical solutions of the translating-pulsating and higher-order Green’s function methods based on traditional Gauss quadrature,it is found that the HOBEM based on analytical quadrature is of better accuracy and *** the non-wall-sided ship,only the present method can produce reasonable pre-diction of motion responses,while obvious oscillatory phenomenon is observed in the results of the other two numerical methods based on Gauss quadrature.

关键词： HOBEM translating-pulsating Green’s function analytical quadrature seakeeping forward speed

Numerical Study on Motion Responses of Two Parallel Ships During Underway Replenishment by the Semi-Analytical HOTP Method

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China Ocean Engineering 2022年第2期36卷 233-246页

作者： YANG yun-tao zhu ren-chuan MA Chao GAO Hui School of Naval Architecture and Civil Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China State Key Laboratory of Ocean Engineering Collaborative Innovation Center for Advanced Ship and Deep-Sea ExplorationSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of High Performance Ship Technology(Wuhan University of Technology) Ministry of EducationWuhan 430063China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China

Motion responses of two ships advancing parallel in waves with hydrodynamic interactions are investigated in this paper. Within the framework of the frequency-domain potential flow theory, a semi-analytical higher-order translating-pulsating source(HOTP) method is presented to solve the problems of coupled radiation and diffraction potential. The method employs nine-node bi-quadratic curvilinear elements to discretize the boundary integral equations(BIEs) constructed over the mean wetted surface of the two ship hulls. In order to eliminate the numerical oscillation, analytical quadrature formulas are derived and adopted to evaluate the integrals related to the Froudedependent part of the Green’s function along the horizontal direction in the BIEs. Based on the method, a numerical program is originally coded. Through the calculations of hydrodynamic responses of single ships, the numerical implementation is proved successful. Then the validated program is applied in the investigations on the hydrodynamic interactions of two identical Wigley Ⅲ hulls and the underway replenishment of a frigate and a supply ship in waves with and without stagger, respectively. The comparison between the present computed results with experimental data and numerical solutions of other methods shows that the semi-analytical HOTP method is of higher accuracy than the pulsating source Green’s function method with speed correction and better stability than the traditional HOTP method based on Gauss quadrature. In addition, for two ships with obviously different dimensions,the influence of hydrodynamic interactions on the smaller ship is found to be more noticeable than that on the larger ship, which leads to the differences between the motions of frigate with and without the presence of supply ship.

关键词： semi-analytical HOTP method two parallel ships underway replenishment coupled motions

TSR: algorithm of image hole-filling based on three-step repairing

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The Journal of China Universities of Posts and Telecommunications 2022年第5期29卷 83-91页

作者： Li Fucheng Deng Junyong zhu yun Luo Jiaying ren Han School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

In order to solve the hole-filling mismatch problem in virtual view synthesis, a three-step repairing(TSR) algorithm was proposed. Firstly, the image with marked holes is decomposed by the non-subsampled shear wave transform(NSST), which will generate high-/low-frequency sub-images with different resolutions. Then the improved Criminisi algorithm was used to repair the texture information in the high-frequency sub-images, while the improved curvature driven diffusion(CDD) algorithm was used to repair the low-frequency sub-images with the image structure information. Finally, the repaired parts of high-frequency and low-frequency sub-images are synthesized to obtain the final image through inverse NSST. Experiments show that the peak signal-to-noise ratio(PSNR) of the TSR algorithm is improved by an average of 2-3 dB and 1-2 dB compared with the Criminisi algorithm and the nearest neighbor interpolation(NNI) algorithm, respectively.

关键词： virtual view point synthesis hole-filling three-step repairing(TSR) Criminisi algorithm curvature driven diffusions(CDD)algorithm

Vanadium Haloperoxidases Model Compounds: Synthesis, Structural Characterization and Mimic Catalytic Bromination Activity of [VO(C_2O_4)(2,2′-bipy)(H_2O)]·C_2H_5OH and VO(C_2O_4)(phen)(H_2O)

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Chemical Research in Chinese Universities 2012年第5期28卷 768-774页

作者： ren Dong-xue CAO yun-zhu CHEN Chen XING Yong-heng College of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 116029R R.China

Two oxo-vanadium（IV） complexes, [VO（C2O4）（2,2′-bipy）（H2O）]·C2H5OH（1） and VO（C2O4）（phen）（H2O）（2）, where 2,2′-bipy=2,2′-bipyridyl, phen=1,10-phenanthroline, were synthesized as potential functional models of vanadium haloperoxidases（VHPOs） in mixed solvent of ethanol and water at room temperature. The complexes were characterized by elemental analysis, infrared（IR）, UV-Vis and X-ray crystallography. Structural analyses showed that vanadium atom was coordinated by a terminal oxygen, one oxygen atom from coordinated water, two oxygen atoms from the carboxylate group of oxalic acid, and two nitrogen atoms（N1 and N2） from 2,2′-bipy/phen. Central vanadium atoms in complexes 1 and 2 were both in a distorted-octahedral environment, and some intermolecular hydrogen bonding linkages were also observed in each complex. Bromination reaction activity of the two complexes was evaluated with phenol red as organic substrate in the presence of H2O2, Br-and phosphate buffer, indicating that they can be considered as a potential functional model of VHPO. In addition, thermal analysis was also performed and discussed in detail.

关键词： Oxo-vanadium complex Bromination reaction activity Vanadium haloperoxidase