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Novel Catalytic Method for Synthesis of Glycosyl Esters by Combining PTC with DMAP

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Chemical Research in Chinese Universities 2007年第4期23卷 426-429页

作者： YANG Song-tao ZHANG Suo-qin ZHANG Guang-liang WANG Xiao-ming li Yao-xian College of Chemistry Jilin University Changchun 130021 P. R. China

This article presents a novel catalytic method by combining phase-transfer catalyst, benzyltriethylammonium chloride, with 4-dimethylaminopyridine for the syntheses of glycosyl esters from substituted phenoxyaeetie acids and the peracetate of α-D-l-bromosugars to produee eight novel β-glyeosyl esters in high yields. The struetures of the syn-thesized eompounds were established by IR, MS, ^1H NMR, and ^13C NMR speetra and elemental analyses.

关键词： Glycosyl ester Substituted phenoxyacetic acid Phase-transfer catalyst 4-Dimethylaminopyridine

Mechanism of high-energy pulsed current-assisted rolling of 08AL carbon steel ultra-thin strip

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Journal of Iron and Steel Research International 2024年第2期31卷 416-427页

作者： Zhong-kai Ren Ya-nan Xu Jia-zhao Chen He li Rui-lin Yuan zhen-hua Wang Tao Wang Xiao liu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment(Ministry of Education) Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710016ShaanxiChina

To improve the plastic deformation performance of a 08AL carbon steel ultra-thin strip,a pulsed electric field was integrated into the plastic processing of the ultra-thin strip,and the effects of high-energy current on its deformation ability were ***-assisted tensile tests were employed,and the results clarified that the pulsed current could reduce the activation energy of faults and promoted dislocation slip within grains and at grain boundaries,leading to a decrease in the deformation resistance of the metal and an increase in its plastic *** the current density of 2.0 A/mm2,the yield strength,tensile strength,and elongation of the rolled sample reached 425 MPa,467 MPa,and 12.5%,*** the rolling process,it was found that the pulsed current promoted the dynamic recrystallization of the ultra-thin strip,reduced its dislocation density and deformation resistance,and promoted the coordinated deformation of the metal.

关键词： 08AL ultra-thin strip High-energy pulsed current Mechanical property Dislocation density Dynamic recrystallization

Identification and activity evaluation of Astragalus Radix from different germplasm resources based on specific oligosaccharide fragments

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Chinese Herbal Medicines 2021年第1期13卷 33-42页

作者： Shu-ying li Di Wang Xian-rong li Xue-mei qin Yu-guang Du Ke li National Glycoengineering Research Center Shandong Key Laboratory of Carbohydrate Chemistry and GlycobiologyShandong UniversityQingdao 266237China Modern Research Center for Traditional Chinese Medicine Shanxi UniversityTaiyuan 030006China College of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan 030006China Shanxi Jianshuo Food and Drug Research Institute Co. Ltd.Taiyuan 030000China Shanxi Academy of Traditional Chinese Medicine Taiyuan 030000China Institure of Process Engineering Chinese Academy of SciencesBeijing 100190China

Objective: Based on trifluoroacetic acid(TFA) hydrolysis, polyacrylamide gel electrophoresis(PAGE) and high performance thin layer chromatography(HPTLC) analysis, the carbohydrate responsible for immunomodulatory activity are used as quality indicators for Astragalus Radix(AR).Methods: In this study, 24 batches of AR from different germplasm resources were selected as the research object, and AR polysaccharides were extracted. PAGE and HPTLC methods were used to analyze the partial acid hydrolyzate of AR polysaccharides and obtain a series of saccharide fingerprints. The data were analyzed by principal component analysis to obtain the difference between AR from different germplasm ***: The results showed that trisaccharide and tetrasaccharide could be used as differential fragments to distinguish AR of different cultivation methods;Disaccharides and trisaccharides can be used as differential fragments to distinguish different species of AR. The immunological activity analysis of the specific oligosaccharide fragment of AR showed that the specific oligosaccharide fragment of AR could promote the secretion of TNF-α, IL-1β, IL-6, and NO in THP-1 cells in a concentration-dependent ***: Both PAGE and HPTLC methods can be used to evaluate AR from different germplasm resources. This study laid the foundation for the quality evaluation of AR medicinal herbs.

关键词： Astragalus Radix germplasm resources hydrolyzate polysaccharide saccharide fingerprints

Schiff-base-rich g-C_(x)N_(4) supported PdAg nanowires as an efficient Mott-Schottky catalyst boosting photocatalytic dehydrogenation of formic acid

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Rare Metals 2021年第4期40卷 808-816页

作者： Hu liu Xue-Xiang li Xin-Yang liu zhen-Hui Ma Zhou-Yang Yin Wei-Wei Yang Yong-Sheng Yu School of Chemistry and Chemical Engineering Xi’an University of Architecture and TechnologyXi'an 710055China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi'an 710072China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China Department of Chemistry Brown UniversityRI 02912USA

Developing an efficient photocatalyst,catalyzing formic acid(FA) dehydrogenation,can satisfy the demand of the H_(2) ***,a graphitic carbon nitride(gC_(x)N_(4))-based nanosheet(x=3.2,3.6 or 3.8) with melem rings conjugated by Schiff-base bond(N=C-C=N) was synthesized,tuning the bandgaps(Eg) of graphitic carbon nitride(g-C_(3) N_(4)) in the range of 1.8 400 nm) without any additive at 25℃,which is the best value among ever-reported *** work provides a new strategy to boost dehydrogenation photocatalysis of FA,which will be promising for practical application of H2 in future energy field.

关键词： Dehydrogenation of formic acid Graphitic carbon nitride Schiff base PdAg nanowires Mott-Schottky heterojunction

Overview of 3D Human Pose Estimation

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1621-1651页

作者： Jianchu lin Shuang li Hong qin Hongchang Wang Ning Cui Qian Jiang Haifang Jian Gongming Wang Huaiyin Institute of Technology Huai’an223000China Jiangsu Outlook Shenzhou Big Data Technology Co. Ltd.Nanjing210002China Institute of Semiconductors Chinese Academy of SciencesBeijing100083China Center of Materials Science and Optoelectronics Engineering&School of Integrated Circuits University of Chinese Academy of SciencesBeijing100049China Inspur Software Group Company Ltd.Jinan250104China China GreatWall Industry Corporation Beijing100054China China GreatWall Industry Corporation Navigation Co. Ltd.Beijing100144China

3D human pose estimation is a major focus area in the field of computer vision,which plays an important role in practical *** article summarizes the framework and research progress related to the estimation of monocular RGB images and *** overall perspective ofmethods integrated with deep learning is *** image-based and video-based inputs are proposed as the analysis *** this viewpoint,common problems are *** diversity of human postures usually leads to problems such as occlusion and ambiguity,and the lack of training datasets often results in poor generalization ability of the *** methods are crucial for solving such *** image-based input,the multi-view method is commonly used to solve occlusion ***,the multi-view method is analyzed *** referring to video-based input,the human prior knowledge of restricted motion is used to predict human *** addition,structural constraints are widely used as prior ***,weakly supervised learningmethods are studied and discussed for these two types of inputs to improve the model generalization *** problem of insufficient training datasets must also be considered,especially because 3D datasets are usually biased and ***,emerging and popular datasets and evaluation indicators are *** characteristics of the datasets and the relationships of the indicators are explained and ***,this article can be useful and instructive for researchers who are lacking in experience and find this field *** addition,by providing an overview of 3D human pose estimation,this article sorts and refines recent studies on 3D human pose *** describes kernel problems and common useful methods,and discusses the scope for further research.

关键词： 3D human pose estimation monocular camera deep learning multi-view indicator

Trajectory prediction of cyclist based on dynamic Bayesian network and long short-term memory model at unsignalized intersections

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Science China(Information Sciences) 2021年第7期64卷 104-116页

作者： Hongbo GAO Hang SU Yingfeng CAI Renfei WU zhengyuan HAO Yongneng XU Wei WU Jianqing WANG Zhijun li zhen KAN Department of Automation University of Science and Technology of China Institute of Advanced Technology University of Science and Technology of China The Dipartimento di Elettronica Informazione e Bioingegneria Politecnico di Milano Automotive Engineering Research Institute Jiangsu University College of Traffic and Transportation Southeast University School of Automation Nanjing University of Science and Technology School of Vehicle and Mobility Tsinghua University

Cyclist trajectory prediction is of great significance for both active collision avoidance and path planning of intelligent vehicles. This paper presents a trajectory prediction method for the motion intention of cyclists in real traffic scenarios. This method is based on dynamic Bayesian network(DBN) and long short-term memory(LSTM). The motion intention of cyclists is hard to predict owing to potential large uncertainties. The DBN is used to infer the distribution of cyclists’ intentions at intersections to improve the prediction time. The LSTM with encoder-decoder is used to predict the cyclists’ trajectories to improve the accuracy of prediction. Therefore, the DBN and LSTM are adopted to guarantee prediction accuracy and improve the prediction time. The experiment results are presented to show the effectiveness of the predict strategies.

关键词： trajectory prediction dynamic Bayesian network (DBN) long short-term memory (LSTM) unsignalized intersections motion intention

Exciton Properties of Diluted CdTe/CdMnTe Quantum Wells

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Chinese Physics Letters 1998年第10期15卷 734-736页

作者： WU Hui-zhen YANG Ai-ling WU Jian-zhong li zheng-zhi Department of Physics Hangzhou UniversityHangzhou 310028 Department of Electronic Engineering Hangzhou UniversityHangzhou 310028

Optical studies of the CdTe/CdMnTe multiple quantum well structures with diluted manganese in barriers are *** combined measurements of photoluminescence and photoluminescence excitation allowed direct observation of the binding energies of n=l heavy-and light-hole free *** quantitative approach of variation of exciton binding energies with well width and barrier potential height is *** calculated and measured exciton binding energies are in good *** studies also show exciton-acoustic phonon scattering dominates the broadening of the exciton line width up to T=50 K,while T>50 K longitudinal-optical phonon scattering contributes to the line width broadening significantly.

关键词： phonon diluted allowed

Non-contact cylindrical rotating triboelectric nanogenerator for harvesting kinetic energy from hydraulics

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Nano Research 2020年第7期13卷 1903-1907页

作者： Nan Zhang Cheng qin Tianxing Feng Jun li Zhirui Yang Xiupeng Sun Erjun liang Yanchao Mao Xudong Wang MOE Key Laboratory of Materials Physics School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Department of Materials Science and Engineering University of Wisconsin-MadisonMadisonWI53706USA

Hydraulics provide a unique and widely existed mechanical energy source around us,such as in water or oil pipes,and ***,a non-contact cylindrical rotating triboelectric nanogenerator(TENG)was developed to harvest the mechanical energy from water *** of the TENG was based on the non-contact free-rotating between a curved Cu foil and a flexible nanostructured fluorinated ethylene propylene(FEP)polymer *** free-standing distance between two rotating interfaces avoided abrading of electrode *** TENG was able to effectively convert mechanical energy of the water flow into *** driven by water flow,the output voltage and current of the TENG reached 1,670 V and 13.4 uA,*** any energy storage component,the produced electricity could instantaneously power 12 white light emitting diodes(LEDs)bulbs and a digital *** non-contact rotating TENG would provide new opportunities for harvesting energy from many types of hydraulics as a self-sustainable power source for sensing,detection,and protection.

关键词： mechanical energy hydraulics triboelectric nanogenerator nanowire thin films non-contact

Frequency-specific Alterations of Large-scale Functional Brain Networks in Patients with Alzheimer＇s Disease

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Chinese Medical Journal 2015年第5期128卷 602-609页

作者： Yuan-Yuan qin Ya-Peng li Shun Zhang Ying Xiong lin-Ying Guo Shi-Qi Yang Yi-Hao Yao Wei li Wen-zhen Zhu Department of Radiology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China Department of Control Science and Engineering Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Huazhong University of Science and Technology Wuhan Hubei 430074 China

Background：Previous studies have indicated that the cognitive deficits in patients with Alzheimer＇s disease （AD） may be due to topological deteriorations of the brain ***,whether the selection of a specific frequency band could impact the topological properties is still not *** hypothesis is that the topological properties of AD patients are also ***：Resting state functional magnetic resonance imaging data from l0 right-handed moderate AD patients （mean age：64.3 years; mean mini mental state examination [MMSE]：18.0） and 10 age and gender-matched healthy controls （mean age：63.6 years; mean MMSE：28.2） were enrolled in this *** global efficiency,the clustering coefficient （CC）,the characteristic path length （CpL）,and ＂small-world＂ property were calculated in a wide range of thresholds and averaged within each group,at three different frequency bands （0.01-0.06 Hz,0.06-0.11 Hz,and 0.11-0.25 Hz）.Results：At lower-frequency bands （0.01-0.06 Hz,0.06-0.11 Hz）,the global efficiency,the CC and the ＂small-world＂ properties of AD patients decreased compared to *** at higher-frequency bands （0.11-0.25 Hz）,the CpL was much longer,and the ＂small-world＂ property was disrupted in AD,particularly at a higher *** topological properties changed with different frequency bands,suggesting the existence of disrupted global and local functional organization associated with ***：This study demonstrates that the topological alterations of large-scale functional brain networks inAD patients are frequency dependent,thus providing fundamental support for optimal frequency selection in future related research.

关键词： Alzheimer's Disease Frequency Network

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