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Chinese Chemical Letters 2011年第12期22卷 1395-1398页

作者： yi yi Weng Jian jun li Wei Ke Su Key Laboratory of Pharmaceutical Engineering of Ministry of Education College of Pharmaceutical Sciences Zhejiang University of Technology Hangzhou 310014 China

A series of（Z）-2-chloro-1,3-diarylpropen-1-ones were unexpectedly synthesized in moderate yields by treatment of easily available 2,3-epoxy-1,3-diarylpropan-1-ones with Vilsmeier reagent,which was derived from bis（trichloromethyl） carbonate（BTC, triphosgene） and DMF.A possible mechanism was also proposed,where sequential ring-opening,halogenation and elimination reactions were involved.

关键词： Ring-opening Halogenation Vilsmeier reagent Bis-(trichloromethyl)carbonate (Z)-2-Chloro-1 3-diaryl-2-enones

A Comprehensive Review of Redirected Walking Techniques:Taxonomy,Methods,and Future Directions

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Journal of Computer Science & Technology 2022年第3期37卷 561-583页

作者： yi-jun li Frank Steinicke Miao Wang State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang UniversityBeijing 100191China Department of Informatics Universität HamburgHamburg 20146Germany Peng Cheng Laboratory Shenzhen 518055China

Virtual reality(VR)allows users to explore and experience a computer-simulated virtual environment so that VR users can be immersed in a totally artificial virtual world and interact with arbitrary virtual ***,the limited physical tracking space usually restricts the exploration of large virtual spaces,and VR users have to use special locomotion techniques to move from one location to *** these techniques,redirected walking(RDW)is one of the most natural locomotion techniques to solve the problem based on near-natural walking *** core idea of the RDW technique is to imperceptibly guide users on virtual paths,which might vary from the paths they physically walk in the real *** a similar way,some RDW algorithms imperceptibly change the structure and layout of the virtual environment such that the virtual environment fits into the tracking *** this survey,we first present a taxonomy of existing RDW *** on this taxonomy,we compare and analyze both contributions and shortcomings of the existing methods in detail,and find view manipulation methods offer satisfactory visual effect but the experience can be interrupted when users reach the physical boundaries,while virtual environment manipulation methods can provide users with consistent movement but have limited application ***,we discuss possible future research directions,indicating combining artificial intelligence with this area will be effective and intriguing.

关键词： virtual reality locomotion redirected walking

VR content creation and exploration with deep learning: A survey

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Computational Visual Media 2020年第1期6卷 3-28页

作者： Miao Wang Xu-Quan Lyu yi-jun li Fang-Lue Zhang State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China. Peng Cheng Laboratory Shenzhen 518000China School of Engineering and Computer Science Victoria University of WellingtonNew Zealand

Virtual reality(VR)offers an artificial,computer generated simulation of a real life *** originated in the 1960 s and has evolved to provide increasing immersion,interactivity,imagination,and *** deep learning systems are able to represent and compose information at various levels in a deep hierarchical fashion,they can build very powerful models which leverage large quantities of visual media *** of VR methods and applications has been significantly boosted by the recent developments in deep learning *** content creation and exploration relates to image and video analysis,synthesis and editing,so deep learning methods such as fully convolutional networks and general adversarial networks are widely employed,designed specifically to handle panoramic images and video and virtual 3 D *** article surveys recent research that uses such deep learning methods for VR content creation and *** considers the problems involved,and discusses possible future directions in this active and emerging research area.

关键词： virtual reality deep learning neural networks 360°image and video virtual content

Theoretical Study on the Structural and Electronic Properties of the Reduced SnO_2 (110) Surface

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Chinese Journal of Structural Chemistry 2007年第5期26卷 606-612页

作者： ZHANG Yong-Fan liN Wei WANG Qi-Wei li yi li jun-Qian Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The reduced SnO2（110） surface has been investigated by using first-principles method with a slab model. By examining the vacancy formation energy of three kinds of reduced SnO2（110） surfaces, the most energetically favorable defect surface is confirmed to be the surface with the coexistence of bridging and in-plane oxygen vacancies, which is different with the traditional model by only removing bridging oxygen. The results of band structure calculations indicate that the electronic structure of this defect surface is similar to the SnO surface.

关键词： SnO2(110) surface band structure defect state

Tensile properties and fracture behavior of friction stir welded joints of Fe-32Mn-7Cr-1Mo-0.3N steel at cryogenic temperature

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Journal of Materials Science & Technology 2018年第1期34卷 157-162页

作者： yi-jun li Rui-dong Fu Yan li Yan Peng Hui-jie liu State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdaa 066004 China State Key Lab of Advanced Welding and Joining Harbin Institute of Technalogy Harbin 150000 China College of Mechanical Engineering Yanshan University Qinhuangdao Hebei 066004 China

This study investigates the cryogenic tensile properties and fracture behavior of fiction stir welded and post-weld heat-treated joints of 32Mn-7Cr-1Mo-0.3N steel. Cryogenic brittle fracture, which occurred in the as-welded joint, is related to the residual particles that contain tungsten in the joint band structure. Post-weld water toughening resulted in the cryogenic intergranular brittleness of the joint, which is related to the non-equilibrium segregation of solute atoms during the post-weld water toughening. Annealing at 55OC for 30rain can effectively inhibit the cryogenic intergranular brittleness of the post- weld water-toughened joint. The yield strength, ultimate tensile strength, and uniform elongation of the annealed joint are approximately 95%, 87%, and 94% of the corresponding data of the base metal.

关键词： High nitrogen steel Friction stir welding Post-weld beat treatment Tensile properties Fracture behavior Cryogenic

Characterization of heat shock protein 90, 70 and their transcriptional expression patterns on high temperature in adult of Graphofita molesta （Busck）

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Insect Science 2014年第4期21卷 439-448页

作者： Hao Chen Xiang-li Xu yi-Ping li jun-Xiang Wu Key Laboratory of Plant Protection Resources and Pest Management (Northwest A&F University) Ministry of Education Key Laboratoryof Appfied Entomology Northwest A&F University Yangling Shaanxi China

Grapholita molesta （Busck） is a worldwide insect pest damaging stone and pome fruits. High temperature can significantly affect insect survival, development and fecundity. Heat shock protein （Hsp） genes were speculated to possess a pivotal function in response to high temperature stress. In this study, two full-length Hsp genes, Gmhsp90 and GmhspTO, were cloned from G. molesta using rapid amplification of complementary DNA ends （RACE）. The open reading frames of Gmhsp90 and Gmhsp70 obtained were 2 148 bp and 1 998 bp in length, respectively. Their deduced amino acids showed high homology to Hsp genes of other species. Subsequently, the transcriptional expression of Gmhsp90 and Gmhsp70 in G. molesta adults exposed at various temperatures （26, 29, 32, 35, 38, 41 and 44℃） for 1 h and at 41℃ for various time duration （0, 15, 30, 45, 60, 75, 90 and 105 min） were investigated via real time quantitative polymerase chain reaction （qPCR）. The relative expression levels of Gmhsp90 and Gmhsp70 in G. molesta adults were both up-regulated with the rise of temperature and time duration. In addition, the Gmhsp70 usually showed a higher transcription accumulation than Gmhsp90. Interestingly, Gmhsp90 and Gmhsp 70 in female adults could be induced much earlier than that in males, and the effective induction temperature in females was also lower than that in males. The distinct expression profiles of Gmhsp90 and Gmhsp 70 indicated that Gmhsp90 and Gmhsp 70 may play important roles in G. molesta adults responding to a thermal threat, and there is difference on induction between sexes.

关键词： Grapholita molesta heat shock protein high temperature sex difference

Elastic-viscoplastic constitutive equations of K439B superalloy and thermal stress simulation during casting process

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中国铸造:英文版 2023年第5期20卷 403-413页

作者： Da-shan Sui Yu Shan Dong-xin Wang jun-yi li Yao Xie yi-qun Yang An-ping Dong Bao-de Sun Institute of Forming Technology&Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Special Rare Metal Materials Northwest Rare Metal Materials Research Institute Ningxia Co.Ltd.Shizuishan 753000NingxiaChina Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

K439B nickel-based superalloy is a new type of high-temperature *** is insufficient research on its constitutive equations and numerical modeling of thermal *** tensile experiments of K439B superalloy at different temperatures(20°C-1,000°C)and strain rates(1.33×10^(-3)s^(-1)-5.33×10^(-3)s^(-1))were performed by using a Gleeble-3800 *** elastic moduli at different temperatures(20°C-650°C)were measured by resonance ***,stress-strain curves were measured for K439B superalloy under different *** elastic-viscoplastic constitutive equations were established and the correspongding parameters were solved by employing the Perzyna *** verification results indicate that the calculated values of the constitutive equations are in good agreement with the experimental *** this basis,the influence of process parameters on thermal stress was investigated by numerical simulation and orthogonal experimental *** results of orthogonal experimental design reveal that the cooling mode of casting has a significant influence on the thermal stress,while pouring temperature and preheating temperature of shell mold have minimal *** distribution of physical fields under optimal process parameters,determined based on the orthogonal experimental design results,was *** simulation results determine separately the specific positions with maximum values for effective stress,plastic strain,and displacement within the *** maximum stress is about 1,000.0 MPa,the plastic strain is about 0.135,and the displacement is about 1.47 ***,the distribution states of thermal stress,strain,and displacement are closely related to the distribution of the temperature gradient and cooling rate in the *** research would provide a theoretical reference for exploring the stress-strain behavior and numerical modeling of the effective stress of the alloy during the casting process.

关键词： nickel-based superalloy investment casting Perzyna model elastic-viscoplastic thermal stress numerical simulation

Finite-time control for periodic systems with random transmission delays

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Finite-time control for periodic systems with random transmi...

Hydrogen-Bonded Engineering Enhancing Phase Transition Temperature in Molecular Perovskite Ferroelastic

第36届中国控制会议

作者： Lu Zhang Renquan Lu jun-yi li Xiao-Meng li Hongyi li The Key Lab for IOT and Information Fusion Technology of Zhejiang the Institute of Information and ControlHangzhou Dianzi University School of Automation Guangdong University of Technologyand Guangdong Key Laboratory of IoT Information Processing

ISBN: (纸本)9781538629185

This paper concentrates on the issue of flnite-time controller design for periodic systems with random transmission delays over networked control *** definitions of stochastic flnite-time stability and flnite-time boundedness are respectively given at the beginning of this ***,based on the Lyapunov function and the linear matrix inequalities（LMIs）technique,the sufficient conditions that can guarantee the system to be flnite-time stable are derived via state *** last,a numerical example is presented to illustrate the effectiveness of the proposed method.

关键词： Networked control systems finite-time control periodic systems random transmission delays

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Chinese Journal of Chemistry 2022年第13期40卷 1559-1565,I0002页

作者： Tie Zhang Kun Ding jun-yi li Guo-Wei Du Lu-Lu Chu yi Zhang Da-Wei Fu Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjingJiangsu211189China

The broad operating temperature range is sought for molecular ferroic materials who are expected to be applied to flexible and electronic *** bonds,an effective force between molecules,are important to regulate the molecule structure and their condition,helping a higher temperature range for ferroic ***,we report a molecular perovskite ferroelastic(Me-Hdabco)Rb[BF_(4)]_(3)(Me-Hdabco=N-methyldabconium)which shows high temperature(T_(1)=322.5 K and T_(2)=381K)ferroelastic phase *** ferroelastic phase transition temperature range of(Me-Hdabco)Rb[BF_(4)]_(3) is significantly increased by 71 K compared with[Meda-bco-F]Rb[BF_(4)]_(3)(Medabco-F=1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane).Structural analysis and thermal analysis demonstrate the ferroelastic phase transition is mainly attributed to dynamic cations order and disorder ***,new hydrogen bonds generated between cations and the Rb_(8)[BF_(4)]_(12) frame increase their intermolecular force,which is beneficial to improving the phase transition *** finding has an important impact on the utilization of weak interactionforces to design and optimize functional materials.

关键词： Molecular dynamics Ferroelastic crystal Dielectric Hydrogen bonds Phase transitions

Microbiome changes in esophageal cancer:implications for pathogenesis and prognosis

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Cancer Biology & Medicine 2024年第2期21卷 163-174页

作者： yi li Bing Wei Xia Xue Hongle li jun li Department of Molecular Pathology Clinical Pathology CenterAffiliated Cancer Hospital of Zhengzhou University and Henan Cancer HospitalZhengzhou 450003China Henan Key Laboratory of Molecular Pathology Zhengzhou 450003China Henan Key Laboratory of Helicobacter pylori&Microbiota and Gastrointestinal Cancer Marshall Medical Research CenterThe Fifth Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Esophageal cancer(EC)is an aggressive malignancy with a poor *** factors,including dietary habits,and antacid and antibiotic use,have been shown to influence the esophageal ***,enrichment and diversity of the esophageal microbiome can also impact its *** studies have revealed prevalent changes in the esophageal microbiome among patients with EC,thus suggesting the potential contribution of the esophageal microbiome to EC ***,distinct microbiome compositions have been observed in patients with different responses to radiotherapy and chemotherapy,indicating the role of the esophageal microbiome in modulating treatment *** this review,we have examined previous studies on the esophageal microbiome in healthy individuals and patients with EC or other esophageal diseases,with a focus on identifying microbial communities associated with EC pathogenesis and *** the role of the microbiome in EC may aid in early detection and optimized treatment strategies,ultimately leading to better outcomes for patients.

关键词： Esophageal cancer microbiome dysbiosis microenvironment carcinogenesis