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C–H allylation of N-aryl-tetrahydroisoquinolines by merging photoredox catalysis with iodide catalysis

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Science China Chemistry 2016年第2期59卷 171-174页

作者： Zhujia Feng Tingting Zeng Jun Xuan Yunhang Liu Liangqiu lu Wen-Jing xiao CCNU-u Ottawa Joint Research Center College of Chemistry Central China Normal University

A dual catalytic system, combing visible light photoredox catalysis and iodide catalysis, has been developed for the functionalization of inert C–H bonds. By doing so, radical allylation reactions of N-aryl-tetrahydroisoquinolines(THIQs) were realized under extremely mild conditions, affording a wide variety of allyl-substituted THIQs in up to 78% yields.

关键词： visible light photocatalysis iodide catalysis allylation tetrahydroisoquinolines

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荧光素快速鉴别酸败食用油的方法研究

粮食与油脂 2024年第9期37卷 158-162页

作者：王韦达杨睿刘晓晗张瑾如张洁吟林长虹深圳市计量质量检测研究院广东深圳518131

建立利用荧光素快速鉴别酸败食用油的方法。在以1.0 mL 5×10^(-5) mol/L荧光素-体积分数95%乙醇溶液为检测液,2 mL体积分数80%异丙醇溶液为前处理提取剂,样品使用量为0.3 mL的条件下,对8种正常食用油和2种酸败食用油进行检测。结果表明... 详细信息

建立利用荧光素快速鉴别酸败食用油的方法。在以1.0 mL 5×10^(-5) mol/L荧光素-体积分数95%乙醇溶液为检测液,2 mL体积分数80%异丙醇溶液为前处理提取剂,样品使用量为0.3 mL的条件下,对8种正常食用油和2种酸败食用油进行检测。结果表明:正常油的检测液颜色和荧光均无变化,2种酸败油的检测液由浅黄色褪至无色,同时荧光发生猝灭,表明建立的方法可以准确地鉴别酸败食用油。与传统检测方法相比,建立的方法可用裸眼和荧光观测结果,适用于现场的快速检测。

关键词：鉴别酸败食用油荧光素

Comprehensive recovery of W,V,and Ti from spent selective reduction catalysts

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Rare Metals 2023年第10期42卷 3518-3531页

作者： Li-Wen Ma xiao-Li Xi Jia-Peng Chen Fan Guo Zi-jie Yang Zuo-Ren Nie Key Laboratory of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China Collaborative Innovation Center of Capital Resource-Recycling Material Technology Beijing University of TechnologyBeijing100124China National Engineering Laboratory for Industrial Big-Data Application Technology Beijing University of TechnologyBeijing100124China

In this study,spent WO_(3)/V_(2)O_(5)-TiO_(2) catalysts used for selective catalytic reduction were treated by a hydrometallurgical process to comprehensively recover valuable metallic elements,such as W,V,and *** and Si impurities were preferentially removed by selective micro wave-assisted alkali leaching.W and V were leached by enhanced high-pressure leaching with efficiencies estimated at 95% and 81%.The leaching of W and V followed the nuclear shrinkage model controlled by the combination of product layer diffusion and interfacial chemical reaction.A synergistic extraction was applied to separate W and V using an extractant mixture of di-(2-ethylhexyl)phosphoric acid P204 and the primary amine *** extraction efficiencies of V and W reached 86.5% and 6.3%,respectively,with a separation coefficient(V/W) of *** product was precipitated after extraction to yield ammonium paratung state(APT) and NH_(4)VO_(3).The TiO_(2)catalyst carrier residue meets commercial specifications for *** comprehensive recovery process with the characteristics of high-pressure leaching and synergistic extraction realizes the resourceful utilization of the spent catalysts.

关键词： Spent selective catalytic reduction(SCR)catalysts Microwaveleaching Pressure leaching Synergistic extraction Comprehensive recovery

Inversion tillage with straw incorporation affects the patterns of soil microbial co-occurrence and multi-nutrient cycling in a Hapli-Udic Cambisol

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Journal of Integrative Agriculture 2023年第5期22卷 1546-1559页

作者： CHEN Xu HAN xiao-zeng WANG xiao-hui GUO Zhen-xi YAN Jun lu Xin-chun ZOU Wen-xiu Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081P.R.China Agricultural Technology Extension Center of Wafangdian City Wafangdian 116300P.R.China Modern Agricultural Development Service Center of Tieling County Tieling 112600P.R.China

Inversion tillage with straw amendment is widely applied in northeastern China, and it can substantially increase the storage of carbon and improve multiple subsoil functions. Soil microorganisms are believed to be the key to this process,but research into their role in subsoil amelioration is limited. Therefore, a field experiment was conducted in 2018 in a region in northeastern China with Hapli-Udic Cambisol using four treatments: conventional tillage(CT, tillage to a depth of 15 cm with no straw incorporation), straw incorporation with conventional tillage(SCT, tillage to a depth of 15 cm),inversion tillage(IT, tillage to a depth of 35 cm) and straw incorporation with inversion tillage(SIT, tillage to a depth of 35 cm). The soils were managed by inversion to a depth of 15 or 35 cm every year after harvest. The results indicated that SIT improved soil multi-nutrient cycling variables and increased the availability of key nutrients such as soil organic carbon, total nitrogen, available nitrogen, available phosphorus and available potassium in both the topsoil and *** contrast to CT and SCT, SIT created a looser microbial network structure but with highly centralized clusters by reducing the topological properties of average connectivity and node number, and by increasing the average path length and the modularity. A Random Forest analysis found that the average path length and the clustering coefficient were the main determinants of soil multi-nutrient cycling. These findings suggested that SIT can be an effective option for improving soil multi-nutrient cycling and the structure of microbial networks, and they provide crucial information about the microbial strategies that drive the decomposition of straw in Hapli-Udic Cambisol.

关键词： soil microbiome microbial co-occurrence networks straw amendment soil nutrient

High-throughput transcriptional profiling of perturbations by Panax ginseng saponins and Panax notoginseng saponins using TCM-seq

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Journal of Pharmaceutical Analysis 2023年第4期13卷 376-387页

作者： Junyun Cheng jie Chen jie Liao Tianhao Wang Xin Shao Jinbo Long Penghui Yang Anyao Li Zheng Wang xiaoyan lu xiaohui Fan Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou310058China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxingZhejiang314100China State Key Laboratory of Medical Molecular Biology Department of Biochemistry and Molecular BiologyInstitute of Basic Medical SciencesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100005China Innovation Center in Zhejiang University State Key Laboratory of Component-Based Chinese MedicineHangzhou310058China Jinhua Institute of Zhejiang University JinhuaZhejiang321016China

Panax ginseng(PG)and Panax notoginseng(PN)are highly valuable Chinese medicines(CM).Although both CMs have similar active constituents,their clinical applications are clearly *** the past decade,RNA sequencing(RNA-seq)analysis has been employed to investigate the molecular mechanisms of extracts or ***,owing to the limited number of samples in standard RNA-seq,few studies have systematically compared the effects of PG and PN spanning multiple conditions at the transcriptomic ***,we developed an approach that simultaneously profiles transcriptome changes for multiplexed samples using RNA-seq(TCM-seq),a high-throughput,low-cost workflow to molecularly evaluate CM perturbations.A species-mixing experiment was conducted to illustrate the accuracy of sample multiplexing in *** from repeated samples were used to verify the robustness of *** then focused on the primary active components,Panax notoginseng saponins(PNS)and Panax ginseng saponins(PGS)extracted from PN and PG,*** also characterized the transcriptome changes of 10 cell lines,treated with four different doses of PNS and PGS,using TCM-seq to compare the differences in their perturbing effects on genes,functional pathways,gene modules,and molecular *** results of transcriptional data analysis showed that the transcriptional patterns of various cell lines were significantly *** exhibited a stronger regulatory effect on genes involved in cardiovascular disease,whereas PNS resulted in a greater coagulation effect on vascular endothelial *** study proposes a paradigm to comprehensively explore the differences in mechanisms of action between CMs based on transcriptome readouts.

关键词： Panax ginseng Panax notoginseng Sample multiplexing RNA sequencing

Symbolic representation based on trend features for knowledge discovery in long time series

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Frontiers of Information Technology & Electronic Engineering 2015年第9期16卷 744-758页

作者： Hong YIN Shu-qiang YANG xiao-qian ZHU Shao-dong MA lu-min ZHANG College of Computer National University of Defense Technology Xiangyang School for NCOs School of Engineering University of Hull

The symbolic representation of time series has attracted much research interest recently. The high dimensionality typical of the data is challenging, especially as the time series becomes longer. The wide distribution of sensors collecting more and more data exacerbates the problem. Representing a time series effectively is an essential task for decision-making activities such as classification, prediction, and knowledge discovery. In this paper, we propose a new symbolic representation method for long time series based on trend features, called trend feature symbolic approximation （TFSA）. The method uses a two-step mechanism to segment long time series rapidly. Unlike some previous symbolic methods, it focuses on retaining most of the trend features and patterns of the original series. A time series is represented by trend symbols, which are also suitable for use in knowledge discovery, such as association rules mining. TFSA provides the lower bounding guarantee. Experimental results show that, compared with some previous methods, it not only has better segmentation efficiency and classification accuracy, but also is applicable for use in knowledge discovery from time series.

关键词： Long time series Segmentation Trend features Symbolic Knowledge discovery

The anti-Temperature-vibration properties of viscoelastic anticorrosive tape

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Petroleum Science 2022年第5期19卷 2413-2419页

作者： Hai-Liang Nie Wei-Feng Ma xiao-Wei Hu Wei Dang Jun-jie Ren Ke Wang Jun Cao Tian Yao xiao-Bin Liang Institute of Safety Assessment and Integrity State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment MaterialsCNPC Tubular Goods Research InstituteXi'an710077China No.2 Oil Extraction Plant Changqing Oilfield BranchPetroChinaGansu745100China

Viscoelastic anticorrosive tape is extensively used for repairing anticorrosive layers on compressor outlet pipelines in the oil and gas ***,there is no relevant research on the coupling effect of temperature and vibration on the performance of viscoelastic anticorrosive *** this paper,acceleration tests of temperature and vibration coupling conditions were conducted to investigate the performance of viscoelastic anticorrosive *** temperature and vibration treatment,the specimens showed wide variance in thickness,and the adhesion and chemical soaking resistance of the tape was ***,the viscoelastic anticorrosive tape still showed high *** to theoretical calculations,the tested viscoelastic body can repair pipes with a maximum diameter of 903 ***,this viscoelastic anticorrosive tape is suitable for the compressor outlets of buried pipelines with diameters smaller than 903 *** research in this paper provides a method and basis for the selection of repairing materials for the anticorrosion coatings of compressor outlet pipelines.

关键词： Station Compressor outlet Anticorrosive coating Viscoelastic anticorrosive tape

Large linear electrostrain of acceptor-donor Co-doped ZnO films

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Journal of Materials Science & Technology 2022年第14期109卷 12-19页

作者： Chang Gao Yu Zhao Weili Li Yulong Qiao Zhao Wang lu Jing jie Sheng Wei-Dong Fei School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Precision Heat Processing of Metals Harbin Institute of TechnologyHarbin 150001China Laboratory for Space Environment and Physical Science Research Center of Basic Space ScienceHarbin Institute of TechnologyHarbin 150001China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

In this paper we present the effective strategy of Fe^(3+)and Li^(+)co-doping to enhance the electrostrain of ZnO thin ***_(0.88)(Fe_(0.06)Li_(0.06))O thin film exhibits an excellent d_(33)^(*)value of 415 pm/V and large linear electrostrain of 0.68%after thermal-electric *** the X-ray diffraction and first principle calculation results have indicated that the Fe^(3+)and Li^(+)ions are inclined to adopt a preferential alignment along the edges approximately parallel to[001]direction in the zinc-oxygen tetrahedron and constitute a defect dipole(ionic pairs).It is considered that the local lattice distortion and the electric field-triggered polarization extension and rotation generated by preferential distributed Fe^(3+)-Li^(+)ionic pairs are responsible for the outstanding piezoelectric properties and large linear electrostrain.

关键词： Zno Piezoelectric Donor-acceptor ionic pairs Local lattice distortion Lead-free

Plate-based cylinder metamaterial with negative Poisson's ratio and outstanding mechanical performance

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Science China(Technological Sciences) 2023年第3期66卷 793-806页

作者： LI Xiang xiao Ran CHEN JuZheng LI JingQi FAN Rong SONG Jian lu Yang School of Sciences Nanjing University of Science and TechnologyNanjing 210094China Nano-Manufacturing Laboratory(NML) Shenzhen Research Institute City University of Hong KongShenzhen 518057China Department of Mechanical Engineering City University of Hong KongHong Kong 999077China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China CityU-Xidian Joint Laboratory of Micro/Nano-Manufacturing Shenzhen 518057China

Plate-based cellular materials exhibit greater stiffness and strength than conventional cellular materials formed by *** this study,we designed and fabricated a plate-based auxetic cylinder metamaterial using high-resolution projection micro-stereolithography three-dimensional printing *** and modeling results validated the auxetic behavior of the plate-based *** normalized Young’s modulus and yield strength of a four-layer auxetic cylinder are increased by 141%and 32%,respectively,compared with the conventional auxetic *** study presents a universal strategy for fabricating plate-based auxetic metamaterials with appropriate mechanical performance for various structural applications.

关键词： auxetic plate-based cylinder mechanical metamaterial 3D printing