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Efficient oxidation of benzyl alcohol with heteropolytungstate as reaction-controlled phase-transfer catalyst

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Chinese Chemical Letters 2007年第8期18卷 936-938页

作者： Zhi Huan weng Jin Yan wang Xi Gao Jian Department of Polymer Science and Materials Dalian University of Technology Liaoning Research Center of High Performance Resin Engineering and Technology Dalian 116012 China

A series of heteropolytungstates has been synthesized and utilized as catalysts to catalyze oxidation of benzyl alcohol with aqueous hydrogen peroxide. The results indicated that three of these catalysts showed the properties of reaction-controlled phasetransfer catalysis, and they had excellent catalytic ability to the oxidation of benzyl alcohol. No other by-products were detected by gas chromatography. Once the hydrogen peroxide was consumed completely, the catalyst precipitated from solvent, and the results of the catalyst recycle showed that the catalyst had high stability.

关键词： Heteropolytungstate Reaction-controlled phase-transfer Benzyl alcohol Benzaldehyde Hydrogen peroxide

A novel fault section locating method based on distance matching degree in distribution network

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Protection and Control of Modern Power Systems 2021年第1期6卷 253-263页

作者： Zhenxing Li Jialing Wan Pengfei wang Hanli weng Zhenhua Li College of Electrical Engineering and New Energy China Three Gorges UniversityYichang443002Hubei ProvinceChina State Grid BoZhou Power Supply Company Maintenance Branch BozhouChina

Fault section location of a single-phase grounding fault is affected by the neutral grounding mode of the system, transition resistance, and the blind zone. A fault section locating method based on an amplitude feature and an intelligent distance algorithm is proposed to eliminate the influence of the above factors. By analyzing and comparing the amplitude characteristics of the zero-sequence current transient components at both ends of the healthy section and the faulty section, a distance algorithm with strong abnormal data immune capability is introduced in this paper. The matching degree of the amplitude characteristics at both ends of the feeder section are used as the criterion and by comparing with the set threshold, the faulty section is effectively determined. Finally, simulations using Matlab/Simulink and PSCAD/EMTDC show that the proposed section locating method can locate the faulty section accurately, and is not affected by grounding mode, grounding resistance, or the blind zone.

关键词： Distribution network Section location Intelligent distance algorithm Wavelet decomposition and reconstruction Matching degree

Determination of 15 phthalate esters in air by gas-phase and particle-phase simultaneous sampling

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Journal of Environmental Sciences 2017年第5期29卷 137-145页

作者： Chenchen Chi Meng Xia Chen Zhou Xueqing wang Mili weng Xueyou Shen College of Environmental & Resource Sciences Zhejiang University Hangzhou 310058 China Zhejiang National Radiation Environmental Technology Co. Ltd. Hangzhou 310011 China School of Environmental and Resource Sciences Zhejiang Agriculture and Forestry University Hangzhou 310058 China Zhejiang Provincial Key Laboratory of Organic PollutionProcess and Control Hangzhou 3100S8 China

Based on previous research, the sampling and analysis methods for phthalate esters （PAEs） were improved by increasing the sampling flow of indoor air from 1 to 4 L/min, shortening the sampling duration from 8 to 2 hr. Meanwhile, through the optimization of chromatographic conditions, the concentrations of 9 additional PAE pollutants in indoor air were measured. The optimized chromatographic conditions required a similar amount of time for analysis as before, but gave high responsivity, the capability of simultaneously distinguishing 15 kinds of PAEs, and a high level of discrimination between individual sample peaks, as well as stable peak generation. The recovery rate of all gas-phase and particle-phase samples of the 15 kinds of PAEs ranged from 91.26% to 109.42%, meeting the quantitative analysis requirements for indoor and outdoor air sampling and analysis. For the first time, investigation of the concentration levels as well as characteristics of 15 kinds of PAEs in the indoor air from four different traffic micro-environments （private vehicles, busses, taxis and subways） was carried out, along with validation of the optimized sampling and analytical method. The results show that all the 9 additional PAEs could be detected at relatively high pollution levels in the indoor air from the four traffic micro-environments. As none of the pollution levels of the 15 kinds of PAEs in the indoor air from the 4 traffic micro-environments should be neglected, it is of great significance to increase the types of PAEs able to be detected in indoor air.

关键词： Air pollution Phthalate esters Traffic micro-environment Gas-phase and particle-phase Sampling and analytical method

基于全局和局部关系的类属特征多标记分类算法

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山东大学学报（理学版） 2024年第5期59卷 23-34页

作者：张珊丹翁伟谢小竹魏博文王劲波文娟厦门理工学院计算机与信息工程学院福建厦门361024 福建省模式识别与图像理解重点实验室福建厦门361024 厦门大学经济学院福建厦门361005

针对忽视局部关系中的二阶标记关系问题,本文提出了一种基于全局和局部关系的类属特征多标记分类(global and lo⁃cal relationships based on multi⁃label classification algorithm with label⁃specific features,LFGML)算法。通过全局关系的角度来获取类属特征,使用加权平均法计算每个实例的邻域信息,利用杰卡德相似度提取局部关系中的二阶标记关系。LFGML算法在10个多标记数据集Genbase、Medical、Arts、Health、Flags、Cal500、Yeast、Image、Education和Emotions进行了实验。结果表明,所提出的算法相对于其他对比算法在多标记分类中具有明显的的性能优势。

关键词：多标记学习全局关系局部关系类属特征优化

PREPARATION OF POLY(METHYL METHACRYLATE)/LAYERED DOUBLE HYDROXIDES NANOCOMPOSITES via in situ SOLUTION POLYMERIZATION

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Chinese Journal of Polymer Science 2007年第6期25卷 573-579页

作者： Ang-ran wang Yong-zhong Bao Zhi-xue weng Zhi-ming Huang State Key Laboratory of Chemical Engineering Zhejiang University Hangzhou 310027 China

An exfoliated layered double hydroxides/poly（methyl methacrylate）（LDHs/PMMA） nanocomposite was prepared by in situ solution polymerization of methyl methacrylate （MMA） in the presence of 4-vinylbenzenesulfonate intercalated LDHs（MgAl-VBS LDHs）. MgAl-VBS LDHs was prepared by the ion exchange method, and the structure and composition of the MgAl-VBS LDHs were determined by X-ray diffraction （XRD）, infrared spectroscopy and elemental analysis. XRD and transmission electron microscopy （TEM） were employed to examine the structure of LDHs/PMMA nanocomposite. It was indicated that the LDHs layers were well exfoliated and dispersed in the PMMA matrix. The grafting of PMMA onto LDHs was confirmed by the extraction result and the weight fraction of grafted PMMA increased as the weight fraction of LDHs in the nanocomposites increased.

关键词： Nanocomposite Poly(methyl methacrylate) Layered double hydroxides.

SDICN: A Software Defined Deployable Framework of Information Centric Networking

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China Communications 2016年第3期13卷 53-65页

作者： wang Xiulei CHEN Ming HU Chao weng Xi XING Changyou College of Command Information System PLA University of Science & Technology

the Information-Centric Networking(ICN) paradigm is proved to have the advantages of decreasing data delivery latency, enhancing user mobility, etc. However, current implementations of ICN require changing the infrastructure of Internet, which hinders its deployment and development. Meanwhile, Software Defined Networking(SDN) emerges as a viable solution to facilitate the deployment of new network paradigm without disrupting production traffic by decoupling the control plane from data forwarding plane. In this paper, the essential properties which reflect ICN working principles are summarized, and a framework called SDICN is designed in accordance to the SDN philosophy. The algorithmic frameworks of SDICN which can satisfy the essential properties are designed based on the programmability and virtualization functions of SDN. Based on Open Flow and data center technology, a prototype of SDICN is implemented. By comparing the performance with the CCNx, the SDICN is proved to be feasibility and availability.

关键词： ICN content routing SDN OpenFlow deployment

Damage evolution and failure mechanism of thermal barrier coatings under Vickers indentation by using acoustic emission technique

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Progress in Natural Science:Materials International 2018年第1期28卷 90-96页

作者： Caicai Li Xing Qiao Teng wang Weixiang weng Qiang Li School of Materials Science and Engineering Fuzhou University

Acoustic emission(AE) technique was adopted to monitor the damage evolution of air plasma-sprayed(APS) yttria-partially-stabilized zirconia(YSZ) thermal barrier coatings(TBCs) during instrumented indentation testing, and then the failure mechanisms were investigated by cluster analysis and wavelet transform *** results of cluster analysis showed that there were three classes associated with distinct failure types for the 8YSZ coatings under Vickers indentation. Based on wavelet transform, these three clusters could be clearly distinguished from their dominant frequency bands, which were concentrated on levels A5(0–156.25 kHz), D5(156.25–312.5 kHz) and D4(312.5–625 kHz), respectively. Thus, the failure mechanism of 8YSZ coatings under Vickers indentation could be clarified by the distribution of different failure types in indentation depth. To sum up, as indentation load increases, the 8YSZ coatings can accommodate the indenter by elastic or little plastic deformation, microcracks propagation and then debonding at the splat boundaries. By comparing the distribution of AE signals induced by different failure types in indentation depth for samples with different thermal exposure time, it can be inferred that thermal exposure treatment can accelerate the degradation of APS 8YSZ TBCs.

关键词： Thermal barrier coatings Instrumented indentation testing Acoustic emission Failure mechanism

Past review,current progress,and challenges ahead on the cocktail party problem

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Frontiers of Information Technology & Electronic Engineering 2018年第1期19卷 40-63页

作者： Yan-min QIAN Chao weng Xuan-kai CHANG Shuai wang Dong YU Tencent AI Lab Tencent Bellevue 98004 USA Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

The cocktail party problem,i.e.,tracing and recognizing the speech of a specific speaker when multiple speakers talk simultaneously,is one of the critical problems yet to be solved to enable the wide application of automatic speech recognition(ASR) *** this overview paper,we review the techniques proposed in the last two decades in attacking this *** focus our discussions on the speech separation problem given its central role in the cocktail party environment,and describe the conventional single-channel techniques such as computational auditory scene analysis(CASA),non-negative matrix factorization(NMF) and generative models,the conventional multi-channel techniques such as beamforming and multi-channel blind source separation,and the newly developed deep learning-based techniques,such as deep clustering(DPCL),the deep attractor network(DANet),and permutation invariant training(PIT).We also present techniques developed to improve ASR accuracy and speaker identification in the cocktail party *** argue effectively exploiting information in the microphone array,the acoustic training set,and the language itself using a more powerful *** optimization ob jective and techniques will be the approach to solving the cocktail party problem.

关键词： Cocktail party problem Computational auditory scene analysis Non-negative matrix factorization Permutation invariant training Multi-talker speech processing

Two-dimensional nanomaterials: fascinating materials in biomedical field

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Science Bulletin 2019年第22期64卷 1707-1727页

作者： Tingting Hu Xuan Mei Yingjie wang Xisheng weng Ruizheng Liang Min Wei State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Orthopaedics Peking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesBeijing 100730China

Due to their high anisotropy and chemical functions,two-dimensional(2D)nanomaterials have attracted increasing interest and attention from various scientific fields,including functional electronics,catalysis,supercapacitors,batteries and energy *** the biomedical field,2D nanomaterials have made significant contributions to the field of nanomedicine,especially in drug/gene delivery systems,multimodal imaging,biosensing,antimicrobial agents and tissue engineering.2D nanomaterials such as graphene/graphene oxide(GO)/reduced graphene oxide(r GO),silicate clays,layered double hydroxides(LDHs),transition metal dichalcogenides(TMDs),transition metal oxides(TMOs),black phosphorus(BP),graphitic carbon nitride(g-C3N4),hexagonal boron nitride(h-BN),antimonene(AM),boron nanosheets(B NSs)and tin telluride nanosheets(Sn Te NSs)possess excellent physical,chemical,optical and biological properties due to their uniform shapes,high surface-to-volume ratios and surface *** this review,we first introduce the properties,structures and synthetic strategies of different configurations of 2D *** advances and paradigms of 2D nanomaterials in a variety of biomedical applications,ranging from drug delivery,cancer treatment,bioimaging and tissue engineering to biosensing are discussed *** the final part,we foresee the development prospects and challenges of 2D nanomaterials after summarizing the research status of ultrathin 2D nanomaterials.

关键词： 2D nanomaterials Drug delivery Tissue engineering Biosensing