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Chinese Chemical Letters 2008年第6期19卷 661-664页

作者： Qi Zhong zhou Chun lin He Zhen Chu Chen Department of Chemistry Zhejiang University Hangzhou 310027 China

Substituted 2-halomethyl-2,3-dihydrobenzofurans were synthesized in one pot and in mild yield from substituted o-allylphenols with diacetoxyiodobenzene in the presence of 12 or Br2 in dry CH2Cl2 under reflux.

关键词： 2-Halomethyl-2,3-dihydrobcnzofuran Diacetoxyiodobenzene Cyclization Halogenation

High-entropy pyrochlores with low thermal conductivity for thermal barrier coating materials

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Journal of Advanced Ceramics 2019年第4期8卷 576-582页

作者： Fei LI lin zhou Ji-Xuan LIU Yongcheng LIANG Guo-Jun ZHANG State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Institute of Functional Materials College of ScienceDonghua University

High-entropy pyrochlore-type structures based on rare-earth zirconates are successfully produced by conventional solid-state reaction method. Six rare-earth oxides(La2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, and Y2O3) and ZrO2 are used as the raw powders. Five out of the six rare-earth oxides with equimolar ratio and ZrO2 are mixed and sintered at different temperatures for investigating the reaction process. The results demonstrate that the high-entropy pyrochlores(5RE1/5)2 Zr2O7 have been formed after heated at 1000 ℃. The(5RE1/5)2Zr2O7 are highly sintering resistant and possess excellent thermal stability. The thermal conductivities of the(5RE1/5)2Zr2O7 high-entropy ceramics are below 1 W·m–1·K–1 in the temperature range of 300–1200 ℃. The(5RE1/5)2Zr2O7 can be potential thermal barrier coating materials.

关键词： thermal barrier coating(TBC) pyrochlore high-entropy ceramics thermal conductivity

Microphone Array Speech Separation Algorithm Based on TC-ResNet

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Computers, Materials & Continua 2021年第11期69卷 2705-2716页

作者： lin zhou Yue Xu Tianyi Wang Kun Feng Jingang Shi School of Information Science and Engineering Southeast UniversityNanjing210096China Center for Machine Vision and Signal Analysis University of OuluOuluFI-90014Finland

Traditional separation methods have limited ability to handle the speech separation problem in high reverberant and low signal-to-noise ratio(SNR)environments,and thus achieve unsatisfactory *** this study,a convolutional neural network with temporal convolution and residual network(TC-ResNet)is proposed to realize speech separation in a complex acoustic environment.A simplified steered-response power phase transform,denoted as GSRP-PHAT,is employed to reduce the computational *** extracted features are reshaped to a special tensor as the system inputs and implements temporal convolution,which not only enlarges the receptive field of the convolution layer but also significantly reduces the network computational *** blocks are used to combine multiresolution features and accelerate the training procedure.A modified ideal ratio mask is applied as the training *** results demonstrate that the proposed microphone array speech separation algorithm based on TC-ResNet achieves a better performance in terms of distortion ratio,source-to-interference ratio,and short-time objective intelligibility in low SNR and high reverberant environments,particularly in untrained *** indicates that the proposed method has generalization to untrained conditions.

关键词： Residual networks temporal convolution neural networks speech separation

Speech Enhancement via Residual Dense Generative Adversarial Network

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Computer Systems Science & Engineering 2021年第9期38卷 279-289页

作者： lin zhou Qiuyue Zhong Tianyi Wang Siyuan Lu Hongmei Hu School of Information Science and Engineering Southeast UniversityNanjing210096China Medizinische Physik and Cluster of Excellence“Hearing4all” Department of Medical Physics and AcousticsUniversity of Oldenburg26129OldenburgGermany

Generative adversarial networks(GANs)are paid more attention to dealing with the end-to-end speech enhancement in recent *** GANbased enhancement methods are presented to improve the quality of reconstructed ***,the performance of these GAN-based methods is worse than those of masking-based *** tackle this problem,we propose speech enhancement method with a residual dense generative adversarial network(RDGAN)contributing to map the log-power spectrum(LPS)of degraded speech to the clean *** detail,a residual dense block(RDB)architecture is designed to better estimate the LPS of clean speech,which can extract rich local features of LPS through densely connected convolution ***,sequential RDB connections are incorporated on various scales of *** significantly increases the feature learning flexibility and robustness in the time-frequency *** show that the proposed method achieves attractive speech enhancement performance in various acoustic ***,in the untrained acoustic test with limited priors,e.g.,unmatched signal-to-noise ratio(SNR)and unmatched noise category,RDGAN can still outperform the existing GAN-based methods and masking-based method in the measures of PESQ and other evaluation *** indicates that our method is more generalized in untrained conditions.

关键词： Generative adversarial networks neural networks residual dense block speech enhancement

Microstructure and properties of W-4.9Ni-2.1Fe heavy alloy with Dy2O3 addition

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Rare Metals 2019年第8期38卷 746-753页

作者： Yuan-Feng Xie Liang-Liang zhou Xiao-Yong Zhang Xiao-Xian Li Zeng-lin zhou Xue-Hui Zhang Institute of Engineering and Technology General Research Institute for Nonferrous Metals Beijing 100088China School of Materials Science and Engineering Jiangxi University of Science and Technology Ganzhou 341000China

The W-4.9 Ni-2.1 Fe-xDy2 O3 heavy alloy was fabricated by high-energy ball milling and spark plasma sintering(SPS)technique,and the microstructure,mechanical and friction behavior and anti-corrosion ability were investigated by scanning electron microscope(SEM),Rockwell hardness tester,X-ray diffraction(XRD),reciprocating friction and wear tester,electrochemical station,*** results show that the trace Dy2 O3 particles,which mainly distributes in the W-M(tungsten-matrix)interface and the tungsten matrix phase,can dramatically decrease the tungsten grain size and the amount of O and P impurities aggregating in the interface,promote the γ-(Ni,Fe)bonding phase and tungsten particles uniform distribution,and increase the relative density,hardness,and wear and corrosion resistance *** the excessive Dy2 O3 addition can make the inhibition effect weaken,resulting in the decrease in the comprehensive performances of the ***,the amount of Dy2 O3 should be *** the adding amount of Dy2 O3 particles is 0.7 wt%,the comprehensive performances of the heavy alloy are the best.

关键词： Dysprosium oxide W-4.9Ni-2.1Fe alloy Spark plasma sintering Mechanical property Anticorrosion ability

Proteolysis targeting chimera technology:a novel strategy for treating diseases of the central nervous system

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Neural Regeneration Research 2021年第10期16卷 1944-1949页

作者： Ke Ma Xiao-Xiao Han Xiao-Ming Yang Song-lin zhou Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury RepairCo-Innovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina College of Life Science Nantong UniversityNantongJiangsu ProvinceChina

Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are *** targeting chimera(PROTAC)technology is a novel strategy to solve this *** technology uses the ubiquitin-protease system to eliminate mutated,denatured,and harmful proteins in *** can be reused,and utilizes the protein destruction mechanism of the cells,thus making up for the deficiencies of traditional protein degradation *** can effectively target and degrade proteins,including proteins that are difficult to identify and ***,it has extremely important implications for drug development and the treatment of neurological *** present,the targeted degradation of mutant BTK,mHTT,Tau,EGFR,and other proteins using PROTAC technology is gaining *** is expected that corresponding treatment of nervous system diseases can be *** review first focuses on the recent developments in PROTAC technology in terms of protein degradation,drug production,and treatment of central nervous system diseases,and then discusses its *** review will provide a brief overview of the recent application of PROTAC technology in the treatment of central nervous system diseases.

关键词： Alzheimer’s disease disease treatment drug development Huntington’s disease proteolysis targeting chimera stroke targeted degradation

Lithofacies identi cation using support vector machine based on local deep multi-kernel learning

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Petroleum Science 2020年第4期17卷 954-966页

作者： Xing-Ye Liu lin zhou Xiao-Hong Chen Jing-Ye Li Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054ShaanxiChina Hunan Provincial Key Laboratory of Shale Gas Resource Utilization Hunan University of Science and TechnologyXiangtan 411201HunanChina State Key Laboratory of Petroleum Resources and Prospecting National Engineering Laboratory for Ofshore Oil ExplorationChina University of Petroleum-BeijingBeijing 102249China

Lithofacies identification is a crucial work in reservoir characterization and *** vast inter-well area can be supplemented by facies identification of seismic ***,the relationship between lithofacies and seismic information that is affected by many factors is *** learning has received extensive attention in recent years,among which support vector machine(SVM) is a potential method for lithofacies *** classification involves identifying various types of lithofacies and is generally a nonlinear problem,which needs to be solved by means of the kernel ***-kernel learning SVM is one of the main tools for solving the nonlinear problem about ***,it is very difficult to determine the kernel function and the parameters,which is restricted by human ***,its computational efficiency is low.A lithofacies classification method based on local deep multi-kernel learning support vector machine(LDMKL-SVM) that can consider low-dimensional global features and high-dimensional local features is *** method can automatically learn parameters of kernel function and SVM to build a relationship between lithofacies and seismic elastic *** calculation speed will be expedited at no cost with respect to discriminant accuracy for multi-class lithofacies *** the model data test results and the field data application results certify advantages of the *** contribution offers an effective method for lithofacies recognition and reservoir prediction by using SVM.

关键词： Lithofacies discriminant Support vector machine Multi-kernel learning Reservoir prediction Machine learning

电气石晶体内微结构对其压电性的影响及机制研究

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矿物学报 2025年第6期44卷 835-844页

作者：薛景源董发勤周琳张伟陈禹衡郑飞郭铭 Leonidovna Kotova Elena 西南科技大学固体废物处理与资源化教育部重点实验室四川绵阳 621010 西南科技大学环境与资源学院四川绵阳 621010 西南科技大学分析测试中心四川绵阳 621010 Mining Museum St. Petersburg Mining University Russia St Petersburg 199106

电气石是一种化学成分和结构复杂的非中心对称晶体，具有压电性。前人鲜有探究电气石内部微结构对其压电性的影响，为了深入探讨电气石晶体内微结构对其压电性的影响，本文研究了锂电气石和镁电气石的晶体内微结构（键长、键角）因素和... 详细信息

电气石是一种化学成分和结构复杂的非中心对称晶体，具有压电性。前人鲜有探究电气石内部微结构对其压电性的影响，为了深入探讨电气石晶体内微结构对其压电性的影响，本文研究了锂电气石和镁电气石的晶体内微结构（键长、键角）因素和压电性之间的联系，通过对电气石进行压电测试及X-射线单晶衍射测试，计算其晶体结构扭曲参数和固有电偶极矩，分析电气石压电性与晶体内微结构的关系。研究发现，Y位置主导元素阳离子半径大小会影响Y多面体内键长、键角扭曲参数，影响Y多面体扭曲变形程度，进而引起晶体中其他多面体发生不同程度的扭曲形变，导致其压电性强弱变化。研究结果表明，Li含量较高的电气石其Y多面体扭曲参数更高，压电性更强。且由于电气石围绕c轴旋转对称的结构导致a、b轴方向上提供的固有电偶极矩相互抵消使得同一种属电气石沿c轴方向上的压电性远强于a、b轴方向，同时发现电气石的固有电偶极矩的大小与电气石的压电性呈现正相关，说明利用固有电偶极矩来研究电气石的压电性能是有意义的。本研究为通过结构参数计算探讨具有压电特性的天然矿物或人造材料微结构对其压电性能的影响机制提供了新思路。

关键词：电气石压电性晶体内微结构 X-射线单晶衍射

Recent progress in thermoelectric nanocomposites based on solution-synthesized nanoheterostructures

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Nano Research 2017年第5期10卷 1498-1509页

作者： Wei Zheng Biao Xu lin zhou Yilong zhou Haimei Zheng Chenghan Sun Enzheng Shi Tanner Dale Fink Yue Wu Department of Chemical and Biological Engineering Iowa State University Ames IA 50011 USA Ames Laboratory Department of Energy Iowa State University Ames IA 50011 USA Material Science Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA

Thermoelectric materials, which can convert waste heat into electricity, have received increasing research interest in recent years. This paper describes the recent progress in thermoelectric nanocomposites based on solution-synthesized nanoheterostructures. We start our discussion with the strategies of improving the power factor of a given material by using nanoheterostructures. Then we discuss the methods of decreasing thermal conductivity. Finally, we highlight a way of decoupling power factor and thermal conductivity, namely, incorporating phase-transition materials into a nanowire heterostructure. We have explored the lead telluride-copper telluride thermoelectric nanowire heterostructure in this work. Future possible ways to improve the figure of merit are discussed at the end of this paper.

关键词： thermoelectrics nanoheterostructures phase change

Structure of GdMg(BO_2)_5 Crystal

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Chinese Journal of Structural Chemistry 2006年第6期25卷 709-713页

作者： FAN Jun-Mei lin zhou-Bin ZHANG Li-Zhen WANG Guo-Fu State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

The title compound GdMg（BO2）s crystallizes in monoclinic, space group P21/n with a = 8.6230（17）, b = 7.5860（15）, c = 9.3777（19） A, β= 93.19（3）°, V = 612.5（2） A3, Z = 4, Mr = 395.61, De= 4.290 g/cm^3,μ = 10.987 mm^-1, F（000） = 724, the final R = 0.0135 and wR= 0.0355 for 1373 observed reflections with I 〉 2σ（I）. The structure consists of BO3 triangles, BO4 tetrahedra, MgO6 distortion octahedra and GdO10 polyhedra. Furthermore, BO3 triangles and BO4 tetrahedra have been verified by infrared spectra. The Gd atoms form infinite zigzag chains along the b axis with the shortest distance of Gd--Gd being 3.958 A. The shorter Gd--Gd will result in a strong interaction between active ions and a large fluorescence concentration quenching effect.

关键词： crystal structure GdMg(BO2)5 crystal