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Symmetric Workpiece Localization Algorithms: Convergence and Improvements

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自动化学报 2006年第3期32卷 428-432页

作者： CHEN Shan-yong li sheng-Yi DAI Yi-Fan School of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073

Symmetric workpiece localization algorithms combine alternating optimization and linearization. The iterative variables are partitioned into two groups. Then simple optimization approaches can be employed for each subset of variables, where optimization of configuration variables is simplified as a linear least-squares problem (LSP). Convergence of current symmetric localization algorithms is discussed firstly. It is shown that simply taking the solution of the LSP as start of the next iteration may result in divergence or incorrect convergence. Therefore in our enhanced algorithms, line search is performed along the solution of the LSP in order to find a better point reducing the value of objective function. We choose this point as start of the next iteration. Better convergence is verified by numerical simulation. Besides, imposing boundary constraints on the LSP proves to be another efficient way.

关键词：对称加工件局限性线性搜索收敛性

Corrosion Behavior of Fe–Al Coatings Fabricated by Pack Aluminizing Method

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 813-819页

作者： Ning-Ning li Min-Zhi Wang yong-sheng li Guang Chen Pei li Engineering Research Center of Materials Behavior and Design Ministry of Education Nanjing University of Science and Technology

In this study, the two kinds of Fe-Al coatings were fabricated by pack aluminizing on low-carbon steel at different temperatures. The corrosion behavior of the Fe-Al coatings in artificial seawater was investigated by the electrochemical and weight loss techniques. Results show that the thickness of coating layer increases with increasing aluminizing temperature. The coatings exhibit high micro-hardness and good metallurgical bonding with the substrate. In comparison with the steel substrate, the corrosion current density Ico^r of the Fe-AI coatings is always lower than that of substrate, about 1/38 or 1/33 after 2 h immersion, and 1/3 or 1/6 for 720 h immersion. As can be seen from the weight loss curve, the Fe-AI coatings show less loss than that of the substrate within 30-day immersion. The corrosion products formed on the surface of the coatings include oxides of Al, Mg, Fe and Ca, and pitting defect has also been found. The Fe-Al coating with higher content of Fe2Al5 has better corrosion resistance.

关键词： Fe-Al coatin2s: Corrosion: Pack aluminizing: X-rav diffraction

Photoresponsive organic field-effect transistors involving photochromic molecules

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Chinese Chemical Letters 2016年第8期27卷 1319-1329页

作者： li-Na Fu Bing Leng yong-sheng li Xi-Ke Gao Laboratory of Low-Dimensional Materials Chemistry Key Laboratory for Ultrafine Materials of the Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and Technology Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of Sciences

In recent years,organic field-effect transistors（OFETs） with high performance and novel multifunctionalities have attracted considerable ***,featured with reversible photoisomerization and the corresponding variation in color,chemical/physical properties,photochromic molecules have been applied in sensors,photo-switches and *** of photochromic molecules to blend in the device functional layers or to modify the interfaces of OFETs is common way to build *** this review,we focus on the recent advantages on the study of photoresponsive transistors involving one of three typical photochromic compounds spiropyran,diarylethene and *** main strategies are demonstrated in ***,photochromic molecules are doped in active layers or combined with semiconductor structure thus forming photoreversible active ***,the modification of dielectric layer/active layer interface is mainly carried out by bilayer ***,the photo-isomerization of self-assembled monolayer（SAM） on the electrode/active layer interface can reversibly modulate the work functions and charge injection barrier,result in bifunctional *** in all,the combination of photochromic molecules and OFETs is an efficient way for the fabrication of organic photoelectric *** transistors consisted of photochromic molecules are potential candidate for real applications in the future.

关键词： Organic field-effect transistors Photoresponsive transistors Photochromic molecules Spiropyran Diarylethene Azobenzene

Experimental Computed Tomography-guided Vena Cava Puncture in Pigs for Percutaneous Brachytherapy of Middle Mediastinal Lymph Node Metastases

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Chinese Medical Journal 2015年第8期128卷 1079-1083页

作者： Min Zhao Bin liu sheng-yong li yong-Zheng Wang Yu-liang li Yancu Hertzanu Physical Examination Centre The Hospital of Shandong University Shandong 250033 China Department of Interventional Medicine The Second Hospital of Shandong University Shandong 250033 China Department of Hepatobiliary Surgery Weihai Municipal Hospital Weihai Shandong 264200 China Faculty of Health Sciences Ben Gurion University of the Negev Beersheba Israel

Background： Percutaneous brachytherapy is a valuable method for the treatment of lung cancer and mediastinal lymph nodes metastasis. However, in some of the metastatic lymph nodes in the middle mediastinum, the percutaneous approach cannot be used safely due to possible damage to surrounding anatomical structures. We established an animal model （group of 12 pigs） to assess the safety and feasibility of computed tomography （CT）-guided vena cava puncture. Methods： Under CT guidance, an 18G needle was used to puncture the anterior wall of the anterior vena cava （AVC） in 12 pigs. The 18G needle was chosen as it is similar in size to the needles employed for clinical application in brachytherapy. The incidence of complications and vital signs was monitored during the procedure. Thoracotomy was performed to remove AVC specimens, which were analyzed for histological evidence of vessel wall damage and repair. Results： Following postoperative enhanced CT, two animals were found to have a small pneumothorax （one being hemopneumothorax）. The intraoperative oxygen saturation of both animals was not significantly decreased and was maintained at 93-100%. No animals developed mediastinal hematoma. Preoperative, intraoperative, and postoperative changes in blood pressure, heart rate, hemoglobin, and blood oxygen saturation were not significant. Histological evaluation of AVC specimens showed that by 7 days following the procedure, the endothelial layer was smooth with notable scar repair in the muscularis layer. Conclusions： CT performed after the procedure and histological preparations confirmed the safety of the procedure. This indicates that percutaneous brachytherapy for metastatic middle mediastinal lymph nodes can be carried out via the superior vena cava.

关键词： Anterior Vena Cava Brachytherapy Computed Tomography-guided Puncture Imaging-based Procedures, Swine

Photoresponsive n-channel organic field-effect transistors based on a tri-component active layer

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Chinese Chemical Letters 2018年第1期29卷 175-178页

作者： li-Na Fu Bing Leng yong-sheng li Xi-Ke Gao Laboratory of Low-Dimensional Materials Chemistry Key Laboratory for Ultrafine Materials of the Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of Sciences

Introducing photochromic molecules into the active layer of organic field-effect transistors （OFETs） is a direct way to implement a photoresponse nature in OFETs. However, active layer blended photo- responsive transistors based on n-type semiconductors are challenging and rarely studied, which are crucial for multifunctional organic-based logic applications. Herein, we fabricated n-channel photo- responsive OFETs based on a tri-component active layer spin-coated from the mixed solution of an n-type semiconductor （NDI2OD-DTYM2）, spiropyran and polystyrene with a weight ratio of 1：1：1. The morphology of the blended films was improved by the introduction of the polymer matrix. Photochromic spiropyran molecules dispersed in the semiconductor layer could switch between the closed-ring state and ionic open-ring state flexibly under the irradiation of different wavelengths of light, and thus change the channel conductivity reversibly and modulate the OFET characteristics. Therefore, under the irradiation of alternate UV and vis light, both the device carrier mobility and current on and off ratio successfully realized a reversible switch.

关键词： Organic field-effect transistorsPhotoresponsen-Type organic semiconductorSpiropyranPolystyrene

Temperature gradient driving interdiffusion interface and composition evolution in Ni-AI-Cr alloys

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Rare Metals 2022年第9期41卷 3186-3196页

作者： yong-sheng li Hui-Yu Wang Jing Chen Shuai-Ge Yang Peng Sang Hong-li Long School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Advanced Metallic and Intermetallic Materials Technology Ministry of Industry and Information Technology of People’s Republic of ChinaNanjing210094China

The interdiffusion interface microstructures and composition evolution of Ni-Al-Cr/Ni-Al-Cr layered alloys under different temperature gradients were studied using phase-field simulation.A precipitate-free zone forms near the interface of the layered alloys,and the interface does not move with time under temperature *** Cr concentrations in the alloy layers are different,Al diffuses from a low-to high-temperature region,whereas Cr from a high-to low-temperature *** width of the precipitate-free zone changes from 0.5 to 2.5μm as the temperature gradient changes fromΔT=0.625 K·μm^(−1) to 1.250 K·μm^(−1);the width of the interdiffusion zone is also ***,the temperature gradient promotes the interdiffusion of elements through the *** contrast,when the initial Al concentration is different in the alloy layers,an uphill diffusion of Al occurs,which is driven by the chemical potential of Al.

关键词： Superalloy Interdiffusion Interface microstructure Phase-field

First-Principle Studies on Adsorption of Cu^+ and Hydrated Cu^+ Cations on Clean Si(111) Surface

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Chemical Research in Chinese Universities 2010年第3期26卷 472-478页

作者： CHENG Feng-ming sheng yong-li li Meng-hua liU yong-jun YU Zhang-yu liU Cheng-bu School of Chemistry and Chemical Engineering School of Environmental Science and Engineering Shandong University Jinan 250100 P. R. China School of Chemistry and Chemical Engineering University of Jinan Jinan 250022 P. R. China

To study the adsorption behavior of Cu^＋ in aqueous solution on semiconductor surface, the interactions of Cu^＋ and hydrated Cu^＋ cations with the clean Si（111） surface were investigated via hybrid density functional theory（B3LYP） and Moller-Plesset second-order perturbation（MP2） method. The clean Si（111） surface was described with cluster models（Si14H17, Si16H20 and Si22H21） and a four-silicon layer slab under periodic boundary conditions. Calculation results indicate that the bonding nature of adsorption of Cu^＋ on Si surface can be viewed as partial covalent as well as ionic bonding. The binding energies between hydrated Cu^＋ cations and Si（111） surface are large, suggesting a strong interaction between them. The coordination number of Cu^＋（H2O）n on Si（111） surface was found to be 4. As the number of water molecules is larger than 5, water molecules form a hydrogen bond network. In aqueous solution, Cu^＋ cations will safely attach to the clean Si（111） surface.

关键词： Silicon surface Copper Ion-solid interaction Adsorption Density functional calculation

Phase-field simulation of re-dissolution of γ’phase in Ni-Al alloy by continuous and second-order aging treatment

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Rare Metals 2021年第5期40卷 1155-1163页

作者： Kun-Wu Lai Shu-Jing Shi Zheng-Wei Yan yong-sheng li sheng-Shun Jin Dong Wang Shahid Maqbool School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology Nanjing 210094China

The morphology and kinetics evolution of the γ’(Ni3 Al)phase during re-dissolution are studied in Ni-15 at% Al alloy,the changes of volume fraction and average particle radius of theγ’phase were clarified with phasefield *** isothermal aging,the interdistance of the neighboringγ’phase affects the interface concentration gradient of Al,which dominates the growth or redissolution of the γ’phase *** isothermal aging at 700 K,the alloy is continuously heated to 900 K with different heating rates,the re-dissolution lag happens,meaning the coalescence coarsening of adjacent γ’phase particles still proceeds at the initial heating *** predissolution of γ’phase with cubic shape is re-dissolved firstly at the edges and corners,in continuous heating to 900 K or by second-order aging from 700 to 900 *** from continuous heating,in the second-order aging process,the connected particles with band shape are broken initially by *** different heating rates,the similar dynamic relationships are abstracted for the volume fraction and the heating rates,and the average particle radius and the heating rates.

关键词： Ni-based superalloy γ’phase Re-dissolution Kinetics

Triarylborane π-electron systems with intramolecular charge-transfer transitions

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Chinese Chemical Letters 2016年第8期27卷 1131-1138,1464页

作者： Zuo-Bang Sun sheng-yong li Zhi-Qiang liu Cui-Hua Zhao School of Chemistry and Chemical Engineering Key Laboratory of Special Functional Aggregated Materials Ministry of EducationShandong University State Key Laboratory of Crystal Materials Shandong University

The incorporation of B element into π-conjugated system is an efficient strategy to tune the steric and electronic structure and thus optoelectronic properties of π-electron *** vacant p orbital on the tricoordinate B center makes it exhibit several electronic and steric features,such as electron-accepting ability through p-π~＊ conjugation,the high Lewis acidity to coordinate with Lewis bases,as well as the steric bulk arising from the aryl substituent on the B center to get enough kinetic *** a result,the boryl group is a very unique electron *** an electron-donating amino group is present,the triarylboranes would display intense intramolecular charge transfer transitions,which lead to interesting optoelectronic properties and great *** short review summarizes the recent progress in π-electron systems,which contain both B and N elements and thus display intramolecular charge-transfer *** triarylboranes are introduced based on their structural features,including the linear π-system with boryl and amino groups at the terminal positions,the lateral borylsubstituted π-system with amino groups at the terminal positions,the biphenyl π-system with an amino and a boryl groups at o,o＇-positions,nonconjugated U- and V-shaped π-system,macrocylcic π-system with B and N embedded in the ring,B,N-bridged ladder-type π-system,as well as the polycyclicπ-system with B embedded in the center.

关键词： Triarylborane Electron-acceptor Electron-donor Charge-transfer