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MoS_2 Nanosheet Arrays Rooted on Hollow rGO Spheres as Bifunctional Hydrogen Evolution Catalyst and Supercapacitor Electrode

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Nano-Micro Letters 2018年第4期10卷 70-80页

作者： shizheng zheng Lijun zheng zhengyou Zhu Jian Chen Jianli Kang Zhulin Huang Dachi Yang Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Department of Electronics College of Electronic Information and Optical Engineering Nankai University School of Material Science and Engineering Tianjin Polytechnic University Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology Institute of Solid State Physics Chinese Academy of Sciences

MoS_2 has attracted attention as a promising hydrogen evolution reaction(HER) catalyst and a supercapacitor electrode material. However, its catalytic activity and capacitive performance are still hindered by its aggregation and poor intrinsic conductivity. Here, hollow rGO sphere-supported ultrathin MoS_2 nanosheet arrays(hrGO@MoS_2) are constructed via a dual-template approach and employed as bifunctional HER catalyst and supercapacitor electrode material. Because of the expanded interlayer spacing in MoS_2 nanosheets and more exposed electroactive S–Mo–S edges, the constructed h-rGO@MoS_2 architectures exhibit enhanced HER performance. Furthermore, benefiting from the synergistic effect of the improved conductivity and boosted specific surface areas(144.9 m^2 g^(-1), ca. 4.6-times that of pristine MoS_2), the h-rGO@MoS_2 architecture shows a high specific capacitance(238 F g^(-1) at a current density of 0.5 A g^(-1)), excellent rate capacitance, and remarkable cycle stability. Our synthesis method may be extended to construct other vertically aligned hollow architectures,which may serve both as efficient HER catalysts and supercapacitor electrodes.

关键词： MoS2 Reduced graphene oxide(rGO) Hollow spheres Hydrogen evolution reaction(HER) Supercapacitor

Improved photocatalytic activity of TiO_2 produced by an alcohothermal approach through in-situ decomposition of NH_4HCO_3

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Journal of Energy Chemistry 2016年第3期25卷 489-494页

作者： Changyuan Hu Chengjiang Lian shizheng zheng Xiaoyu Li Tiewen Lu Quanhong Hu Shuwang Duo Rongbin Zhang Yingying Sun Fei Chen Jiangxi Key Laboratory of Surface Engineering Jiangxi Science and Technology Normal University School of Materials and Mechanical & Electrical Engineering Jiangxi Science and Technology Normal University Chemistry and Chemical Engineering College Jiangxi Science and Technology Normal University College of Chemistry Nanchang University

High crystallinity of TiOwas prepared by a modified alcohothermal method, in which titanium isopropoxide was used as the titania precursor, absolute ethanol as the reaction medium, and NHHCOas the raw materials for release of water, ammonia and carbon dioxides via in-situ decomposition. The X-ray powder diffraction（XRD） and transmission electron microscope（TEM） measurements showed that water and ammonia from the in-situ decomposition of NHHCOplayed an important role in conducting the size, shape, crystallinity and microstructure of TiO. The photoluminescence spectroscopy and photocurrent measurements indicated that enhanced crystallinity could hinder the recombination and promote the separation of electron-hole pairs in TiO, which contribute to the improvement of photocatalytic *** orange photodegradation under UV light confirmed that high crystallinity of TiOdid present a high photocatalytic activity due to the effective separation of photoinduced charges.

关键词： Titanium dioxide Solvothermal method NH_4HCO_3 Photocatalysis

条件非线性最优扰动和繁殖向量相结合的一种集合预报方法

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科学通报 2017年第21期62卷 2392-2398页

作者：周仕政郑琴沙建新解放军理工大学理学院解放军94906部队

集合初始扰动的好坏对集合预报效果有着至关重要的影响.为了产生能够捕捉到初始场不确定性的初始扰动,在不考虑模式误差的情况下,用Lorenz-96模式探讨了条件非线性最优扰动(conditional nonlinear optimal perturbation,CNOP)在集合预... 详细信息

集合初始扰动的好坏对集合预报效果有着至关重要的影响.为了产生能够捕捉到初始场不确定性的初始扰动,在不考虑模式误差的情况下,用Lorenz-96模式探讨了条件非线性最优扰动(conditional nonlinear optimal perturbation,CNOP)在集合预报中的应用,并与传统的增长繁殖模方法(breeding of growing mode,BGM)进行了比较.发现用CNOPs代替2L范数较大的繁殖向量(breeding vectors,BVs)的集合预报技巧明显高于BGM方法.在分析误差是快速增长型扰动的条件下,新方法对预报结果的改善幅度随预报时间的延长而增大,特别是在中期预报范围(6~14 d)内,改善效果更加明显.按照通常距平相关系数(ACC)不小于0.6则视为有效预报的标准,新方法和BGM方法得到的集合预报相对于参照预报而言,都能够将有效预报时间延长4 d左右.

关键词：集合预报条件非线性最优扰动繁殖向量预报技巧

基于改进灰度重心法的轨道扣件重构与故障诊断

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中国激光 2024年第8期51卷 85-93页

作者：肖圳孙世政郑天成庞珂魏子杰重庆交通大学机电与车辆工程学院重庆400074

针对轨道扣件表面结构复杂导致的线结构光照射分布不均匀问题,研究了一种基于改进灰度重心法的光条中心线提取方法,精准重构了轨道扣件点云模型。基于点云模型提取了轨道扣件的结构特征信息,建立了轨道扣件缺陷检测组合分类器模型,实现... 详细信息

针对轨道扣件表面结构复杂导致的线结构光照射分布不均匀问题,研究了一种基于改进灰度重心法的光条中心线提取方法,精准重构了轨道扣件点云模型。基于点云模型提取了轨道扣件的结构特征信息,建立了轨道扣件缺陷检测组合分类器模型,实现了轨道扣件的弹条缺失、扣件歪斜、螺母缺失等缺陷检测。研究了基于表面法向量的螺母上平面解析方法,通过螺母松动测量实验实现了轨道扣件的松动检测。搭建了扣件故障诊断实验平台并开展了相关实验研究,实验结果表明,系统扣件故障检出率达到96%,扣件松紧度测量的总体误差低于0.2 mm,扣件故障诊断系统的检测效果和鲁棒性较好,对列车安全运行具有重要的现实意义。

关键词：测量三维图像处理轨道扣件线结构光中心线提取故障诊断

A telomere-to-telomere genome assembly of Zhonghuang 13,a widely-grown soybean variety from the original center of Glycine max

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The Crop Journal 2024年第1期12卷 142-153页

作者： Anqi Zhang Tangchao Kong Baiquan Sun shizheng Qiu Jiahe Guo Shuyong Ruan Yu Guo Jirui Guo Zhishuai Zhang Yue Liu zheng Hu Tao Jiang Yadong Liu Shuqi Cao Shi Sun Tingting Wu Huilong Hong Bingjun Jiang Maoxiang Yang Xiangyu Yao Yang Hu Bo Liu Tianfu Han Yadong Wang Center for Bioinformatics School of Computer Science and TechnologyHarbin Institute of TechnologyHarbin 150001HeilongjiangChina Ministry of Agriculture Key Laboratory of Soybean Biology(Beijing) Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

Soybean(Glycine max)stands as a globally significant agricultural crop,and the comprehensive assembly of its genome is of paramount importance for unraveling its biological characteristics and evolutionary ***,previous soybean genome assemblies have harbored gaps and incompleteness,which have constrained in-depth investigations into ***,we present Telomere-to-Telomere(T2T)assembly of the Chinese soybean cultivar Zhonghuang 13(ZH13)genome,termed ZH13-T2T,utilizing PacBio Hifi and ONT ultralong *** employed a multi-assembler approach,integrating Hifiasm,NextDenovo,and Canu,to minimize biases and enhance assembly *** assembly spans 1,015,024,879 bp,effectively resolving all 393 gaps that previously plagued the reference *** annotation efforts identified 50,564 high-confidence protein-coding genes,707 of which are ***13-T2T revealed longer chromosomes,421 not-aligned regions(NARs),112 structure variations(SVs),and a substantial expansion of repetitive element compared to earlier ***,we identified 25.67 Mb of tandem repeats,an enrichment of 5S and 48S rDNAs,and characterized their genotypic *** summary,we deliver the first complete Chinese soybean cultivar T2T *** comprehensive annotation,along with precise centromere and telomere characterization,as well as insights into structural variations,further enhance our understanding of soybean genetics and evolution.

关键词： Soybean Telomere-to-Telomere assembly Zhonghuang 13 Structure variations

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放射性气溶胶自适应分离设计与特性研究

重庆理工大学学报（自然科学） 2024年第6期38卷 127-132页

作者：何泽银黄思成孙世政郑天成重庆交通大学机电与车辆工程学院重庆400074

研究针对不同颗粒物密度环境下人工放射性气溶胶氡的分离与监测,提出了一种基于虚拟冲击原理的环境自适应分离技术。基于虚拟冲击原理,建立亚微米虚拟冲击器二维模型。结合流体动力学,数值计算虚拟冲击器在不同颗粒物密度、结构和流量... 详细信息

研究针对不同颗粒物密度环境下人工放射性气溶胶氡的分离与监测,提出了一种基于虚拟冲击原理的环境自适应分离技术。基于虚拟冲击原理,建立亚微米虚拟冲击器二维模型。结合流体动力学,数值计算虚拟冲击器在不同颗粒物密度、结构和流量条件下内流道分离效率与壁面损失,阐明多因素对分离效率的影响规律,揭示亚微米虚拟冲击器在不同颗粒物密度下对氡气溶胶的自适应分离规律。结果表明,亚微米虚拟冲击器对氡气溶胶的分离曲线陡度较好,具有良好的分离性能与较低的壁面损失;颗粒物密度与流量因素对分离效率的影响大于结构因素;亚微米虚拟冲击器自适应流量调节可实现不同颗粒物密度下氡气溶胶的高效分离,颗粒物密度为2200 kg/m 3时亚微米虚拟冲击器较自适应前分离效率提升18.35%且具有较低的壁面损失。

关键词：虚拟冲击器环境自适应数值模拟分离效率

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正癸烷/空气旋转爆轰波形成与传播数值模拟

哈尔滨工程大学学报 2024年第4期45卷 730-738页

作者：邵晓峰赵宁波刘世铮孟庆洋李雅军郑洪涛哈尔滨工程大学动力与能源工程学院黑龙江哈尔滨150001 中国船舶集团有限公司第七〇三研究所黑龙江哈尔滨150078

针对气液两相旋转爆轰波形成与传播问题,本文以液态正癸烷为燃料,采用欧拉-拉格朗日方法,通过三维数值模拟给出了两相旋转爆轰波的形成演变特点和自持传播机理。研究结果表明:在起爆阶段,通过调控初始燃料分布能够获得强度不同的爆轰波... 详细信息

针对气液两相旋转爆轰波形成与传播问题,本文以液态正癸烷为燃料,采用欧拉-拉格朗日方法,通过三维数值模拟给出了两相旋转爆轰波的形成演变特点和自持传播机理。研究结果表明:在起爆阶段,通过调控初始燃料分布能够获得强度不同的爆轰波和压力波;在对撞阶段,爆轰波与压力波共发生4次对撞,由于缺乏燃料供给,压力波逐渐衰减并消失,爆轰波以单波模态传播;在稳定传播阶段,未燃燃料在三叉点处聚集形成未反应气流区并诱导产生局部爆炸。未反应气流区的周期性出现和局部爆炸是两相爆轰波自持传播的重要影响因素。

关键词：正癸烷气液两相非预混旋转爆轰掺混流场特性自持传播未反应气流区

An intensive study on aerosol optical properties and affecting factors in Nanjing,China

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Journal of Environmental Sciences 2016年第2期28卷 35-43页

作者： Fenping Cui Mindong Chen Yao Ma Jun zheng Zhou Yaoyao shizheng Li Lu Qi Li Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring & Pollution Control Nanjing 210044China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing 210044China School of Physics & Opto-electronic Engineering Nanjing University of Information Science & TechnologyNanjing 210044China School of Environmental Science and Engineering Nanjing University of Information Science & TechnologyNanjing 210044China

The optical properties of aerosol as well as their impacting factors were investigated at a suburb site in Nanjing during autumn from 14 to 28 November 2012. More severe pollution was found together with lower visibility. The average scattering and absorption coefficients（B sca and B abs） were 375.7 ± 209.5 and 41.6 ± 18.7 Mm^（-1）, respectively. Higher ？ngstr？m absorption and scattering exponents were attributed to the presence of more aged aerosol with smaller particles. Relative humidity（RH） was a key factor affecting aerosol extinction. High RH resulted in the impairment of visibility, with hygroscopic growth being independent of the dry extinction coefficient. The hygroscopic growth factor was 1.8 ± 1.2 with RH from 19% to 85%.Light absorption was enhanced by organic carbon（OC）, elemental carbon（EC） and EC coatings,with contributions of 26%, 44% and 75%（532 nm）, respectively. The B sca and B abs increased with increasing N_（100）（number concentration of PM_（2.5）with diameter above 100 nm）, PM_1 surface concentration and PM_（2.5）mass concentration with good correlation.

关键词： Aerosol optical properties Single scattering albedo Angstrom exponent Hygroscopic growth factor

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电容对石英晶体微天平质量灵敏度影响分析

国外电子测量技术 2024年第7期43卷 170-175页

作者：孙世政郑天成何泽银黄思成刘鑫鹏重庆交通大学机电与车辆工程学院重庆400074

为探究振荡电路中电容对石英晶体微天平质量灵敏度的影响,提出了振荡电路的等效电路模型阻抗分析方法。首先,建立等效电路模型,分析阻抗与频率关系,揭示了电容容值与其质量灵敏度对应关系;其次,进行多物理场耦合仿真实验,探究了电容容... 详细信息

为探究振荡电路中电容对石英晶体微天平质量灵敏度的影响,提出了振荡电路的等效电路模型阻抗分析方法。首先,建立等效电路模型,分析阻抗与频率关系,揭示了电容容值与其质量灵敏度对应关系;其次,进行多物理场耦合仿真实验,探究了电容容值对其质量灵敏度的影响规律;最后,搭建实验系统平台,开展了质量灵敏度实验。结果表明,并联电容对其质量灵敏度影响较小;串联1.01 pF电容其质量灵敏度提升8.01×10^(-2)Hz/ng,串联15.84 pF电容其质量灵敏度提升1.49×10^(-2)Hz/ng。该结论有助于更好地理解电容对石英晶体微天平质量灵敏度影响,为该类传感器便携化、微型化设计提供有力支持。

关键词：石英晶体微天平质量灵敏度压电效应阻抗分析