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Phosphorous and selenium tuning Co-based non-precious catalysts for electrosynthesis of H_(2)O_(2)in acidic media

Chinese Chemical Letters 2024年第1期35卷 475-481页

作者： jingxin xie Lijie Zhong Xin Yang Dequan He Kanglong Lin Xiaoxia Chen Huan Wang Shiyu Gan Li Niu Guangdong Engineering Technology Research Center for Photoelectric Sensing Materials&Devices Guangzhou Key Laboratory of Sensing Materials&DevicesCenter for Advanced Analytical ScienceSchool of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006China Department of Chemistry and Environment Science Fujian Provincial Key Laboratory of Modern Analytical Science and Separation TechnologyMinnan Normal UniversityZhangzhou 363000China

Electrosynthesis of hydrogen peroxide(H2O2)is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable *** crucial point remains developing highly active,selective and cost-effective *** electrosynthesis of H2O2 in acidic media is more practical owing to its stability and no need for further *** herein report a phosphorus and selenium tuning Co-based non-precious catalyst(CoPSe)toward two-electron oxygen reduction reaction(2e–ORR)to produce H2O2 in acidic *** starting point of using both P and Se is finding a balance between strong ORR activity of CoSe and weak activity of *** results demonstrated that the CoPSe catalyst exhibited the optimized 2e–ORR activity compared with CoP and *** disclosed an onset potential of 0.68 V and the H2O2 selectivity 76%-85%in a wide potential range(0–0.5 V).Notably,the CoPSe catalyst overcomes a significant challenge of a narrow-range selectivity for transitionmetal based 2e–ORR ***,combining with electro-Fenton reaction,an on-site system was constructed for efficient degradation of organic *** work provides a promising non-precious Co-based electrocatalyst for the electrosynthesis of H2O2 in acidic media.

关键词： Oxygen reduction reaction Electrochemical H2O2 production Electrocatalysis Non-precious electrocatalyst Acidic media

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城镇化发展中后期我国农村劳动力迁移年龄模式研究——基于迁移次序和队列差异视角

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人口与经济 2024年第3期 57-69页

作者：王亚楠谢晶鑫河海大学经济与金融学院江苏常州213200

随着我国城镇化发展进入中后期,农村劳动力迁移呈现增速放缓以及回流趋势,在当前农村人口总量依然庞大、农业与非农部门劳动生产率仍存在较大差距的背景下,上述变化趋势显然有悖于刘易斯二元经济理论框架下的劳动力迁移规律。基于迁移... 详细信息

随着我国城镇化发展进入中后期,农村劳动力迁移呈现增速放缓以及回流趋势,在当前农村人口总量依然庞大、农业与非农部门劳动生产率仍存在较大差距的背景下,上述变化趋势显然有悖于刘易斯二元经济理论框架下的劳动力迁移规律。基于迁移次序和队列差异视角,利用中国劳动力动态调查(CLDS)数据,采用二元选择模型和多层次APC—交叉分类随机效应模型,理论探讨并实证检验我国农村劳动力初次迁移与回流再迁移、不同出生队列劳动力初次迁移的年龄模式差异,以期深入理解劳动力迁移规律并准确研判未来发展趋势。研究发现:第一,回流劳动力的再迁移意愿显著大于从未迁移劳动力的初次迁移意愿,在20—45岁的中青年劳动力群体中体现得最为明显;第二,我国农村劳动力初次迁移行为具有典型的年龄特征且存在明显的队列差异,越晚出生队列初次迁移率与年龄倒“U”型关系越显著,尖峰态势越明显。为推动我国城镇化水平持续提升、促进城乡统一劳动力大市场形成,建议应重点围绕提升农村人口自然增长水平、加强中青年劳动力迁移稳定性以及挖掘农村中老年劳动力迁移潜力制定适应性政策。

关键词：劳动力迁移年龄模式迁移次序队列差异

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纳米碳材料在低碳烷烃直接脱氢中应用的研究进展

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石油学报（石油加工） 2024年第4期40卷 1002-1012页

作者：王玮谢婧新于鹏吴耿煌宗明生荣峻峰中石化石油化工科学研究院有限公司北京100083

低碳烷烃直接脱氢是生产低碳烯烃的重要方式,其关键在于催化剂。纳米碳材料原料来源广泛、存在形式多样且结构可调变性强,获得了研究者们的广泛关注。基于纳米碳材料在低碳烷烃直接脱氢领域中的研究现状,总结了纳米碳催化剂及以纳米碳... 详细信息

低碳烷烃直接脱氢是生产低碳烯烃的重要方式,其关键在于催化剂。纳米碳材料原料来源广泛、存在形式多样且结构可调变性强,获得了研究者们的广泛关注。基于纳米碳材料在低碳烷烃直接脱氢领域中的研究现状,总结了纳米碳催化剂及以纳米碳材料为载体的Pt/纳米碳催化剂催化低碳烷烃直接脱氢的反应机理,分析了元素掺杂、缺陷改性和形貌调控这3种修饰方式对纳米碳催化剂及Pt/纳米碳催化剂的电子结构、几何形貌及其脱氢性能的影响。未来可以结合原位表征和理论计算深入研究修饰方式的作用机理,指导制备脱氢性能优异的纳米碳催化剂及Pt/纳米碳催化剂,并通过系统研究催化剂成型及再生工艺推动催化剂的工业化应用。

关键词：纳米碳材料烷烃脱氢元素掺杂缺陷改性形貌调控催化剂

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定量核磁共振氢谱法测定4种盐酸莫西沙星杂质对照品的含量

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中国药学杂志 2024年第12期59卷 1151-1155页

作者：何雨张雅军谢晶鑫王青邵长军孙会敏路勇吴先富中国食品药品检定研究院北京102629

目的建立测定4种盐酸莫西沙星杂质A、B、C、D对照品含量的定量核磁共振氢谱法(quantitative proton nuclear magnetic resonance,qHNMR)。方法采用核磁共振波谱仪采集4种盐酸莫西沙星杂质对照品的一维定量氢谱(^(1)H-NMR),以1,3,5-三甲... 详细信息

目的建立测定4种盐酸莫西沙星杂质A、B、C、D对照品含量的定量核磁共振氢谱法(quantitative proton nuclear magnetic resonance,qHNMR)。方法采用核磁共振波谱仪采集4种盐酸莫西沙星杂质对照品的一维定量氢谱(^(1)H-NMR),以1,3,5-三甲氧基苯作为内标物,氘代二甲亚砜(DMSO-d6)或氘代氯仿(CDCl_(3))作为溶剂,脉冲程序为noesyigld1d,扫描次数(NS)为32次,弛豫延迟时间(D1)为30 s,测试温度为25℃,对4种盐酸莫西沙星杂质对照品进行定量研究。结果4种盐酸莫西沙星杂质对照品定量峰和1,3,5-三甲氧基苯定量峰信号在核磁共振氢谱上分离度良好,在线性范围内线性关系良好(r^(2)>0.9994),进样精密度和重复性良好。qHNMR法测定含量结果与质量平衡法测定含量结果基本一致。结论建立的qHNMR法准确可靠、简便快速,为该类杂质含量测定提供了新的方法,也可作为该类化学对照品采用质量平衡法定值结果的验证方法。

关键词：定量核磁共振氢谱法盐酸莫西沙星杂质对照品定值含量测定

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Carbon Encapsulated Nickel Nanocomposites for the Cathode in Advanced Lithium Sulfur Batteries

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China Petroleum Processing & Petrochemical Technology 2021年第4期23卷 1-6页

作者： Yang Yuxiang xie jingxin Wu Genghuang Zhu Na Li Huan Rong Junfeng SINOPEC Research Institute of Petroleum Processing Beijing 100083

Lithium sulfur(Li-S)batteries are poised to be the next generation of high-density energy storage *** recent years,the concept of“electrocatalysis”has been introduced into the field of Li-S batteries,and some transition metals have been proved to catalyze the electrochemical conversion reaction of sulfur *** this study,carbon encapsulated nickel nanoparticles(Ni@C)with a specific surface area of 146 m^(2)/g are shown to play a definitive electrocatalytic role for the sulfur *** Ni@C incorporated,the Ni@C/G-S electrode achieved a better electrochemical performance than the G-S ***,the reversible capacity and cycle stability were further improved through chemical modifications of the carbon *** influence of doping with different elements on the Li-S battery performance was also investigated in *** specific capacities of 1229 mA·h/g,927 mA·h/g,and 830 mA·h/g were achieved at 0.2 C,0.5 C,and 1.0 C for the N-Ni@C-G/S ***,the B-Ni@C-G/S electrode possessed a best cycle stability.

关键词： lithium sulfur batteries electrocatalysis electrochemical conversion reaction Ni@C chemical modifications

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Cost-effective method for degradability identification of MSW using convolutional neural network for on-site composting

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 233-237页

作者： Jingjing Huang Sihui Dai Heming Hu Hongduo Zhang jingxin xie Ming Li Hunan Agricultural University Changsha 410128China Hunan Agricultural Equipment Research Institute Changsha 410125China Graduate School of Agricultural and Life Sciences the University of TokyoTokyo 113-0033Japan

Automatically identifying the degradability of municipal solid waste(MSW)is one of the key prerequisites for on-site composting to prevent contaminations from undegradable *** this study,a cost-effective method was proposed for the degradability identification of ***,the trainable images in the datasets were increased by performing four different sizes of cropping operations on the original images captured ***,a lite convolutional neural network(CNN)model was built with only 3.37 million parameters,and then a total of eight models were trained on these datasets with and without the image augmentation operations,***,a degradability identification system was built for on-site composting,where the images were cut to different sizes of small squares for prediction,and the experiments were conducted to find the best combinations of the trained models and the cutting *** results showed that the validation accuracies of the models trained with the augmentation operations were 0.91-2.07 percentage points higher,and in the evaluation of the degradability identification system the best result was achieved by the combination of W8A dataset and cutting size of 1/14 reached an accuracy of 91.58%,which indicated the capability of this cost-effective method to identify the degradability of MSW.

关键词： municipal solid waste degradability identification cost-effective CNN on-site composting image classification

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Ultrafine Co nanoparticles confined in nitrogen-doped carbon toward two-electron oxygen reduction reaction for H_(2)O_(2) electrosynthesis in acidic media

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Chinese Chemical Letters 2023年第11期34卷 263-268页

作者： Xiaoqing Cui Lijie Zhong Xu Zhao jingxin xie Dequan He Xin Yang Kanglong Lin Huan Wang Li Niu Guangdong Engineering Technology Research Center for Sensing Materials&Devices Guangzhou Key Laboratory of Sensing Materials&DevicesCenter for Advanced Analytical ScienceSchool of Chemistry and Chemical EngineeringSchool of Civil EngineeringGuangzhou UniversityGuangzhou 510006China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Electrocatalytic production of hydrogen peroxide(H_(2)O_(2))by two-electron oxygen reduction reaction(2e^(-)ORR)under acidic condition has been considered to have great application *** nanoparticles(CoNPs)coupled with N-doped carbon are a class of potential *** effective strategies to further enhance their performances are to improve the active sites and ***,the material containing ultrafine CoNPs confined in a nitrogen-doped carbon matrix(NC@CoNPs)was synthesized by pyrolyzing corresponding precursors,which was obtained through regulating the topological structure of ZIF-67/ZIF-8 with dopamine(DA).The DA self-polymerization process induced the formation of CoNPs with smaller sizes and formed polydopamine film decreased the detachment of CoNPs from the *** density of Co-N_(x) active sites and defective sites could be identified on NC@CoNPs,leading to high activity and H_(2)O_(2) selectivity,with an onset potential of 0.57 V(***)and∼90%selectivity in a wide potential *** on-site electrochemical removal of organic pollutant was achieved rapidly through an electro-Fenton process,demonstrating its great promise for on-site water treatment application.

关键词： Oxygen reduction reaction H_(2)O_(2)production Confined Co nanoparticles Electrocatalysis Acidic media

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一种消除椒盐噪声的迭代自适应加权均值滤波

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青岛大学学报（工程技术版） 2024年第3期39卷 39-45页

作者：秦承刚张建施赣明张学阁谢敬心徐世许山东中烟工业有限责任公司青岛卷烟厂山东青岛266101 山东中烟工业有限责任公司山东济南250014 青岛大学自动化学院山东青岛266071

针对传统的均值滤波和多种中值滤波不能有效去除高密度椒盐噪声的不足,提出一种迭代自适应加权均值滤波算法。为了能够对图像外围的像素点进行滤波,沿四周进行图像扩展。根据椒盐噪声的极值特性,将像素点分为噪声点和信号点,噪声点采用... 详细信息

针对传统的均值滤波和多种中值滤波不能有效去除高密度椒盐噪声的不足,提出一种迭代自适应加权均值滤波算法。为了能够对图像外围的像素点进行滤波,沿四周进行图像扩展。根据椒盐噪声的极值特性,将像素点分为噪声点和信号点,噪声点采用多轮迭代,利用前次滤波的结果,求取滤波窗口非噪声点灰度值的加权均值,基于与窗口中心像素的空间距离计算加权系数;信号点保持原值。滤波窗口尺寸根据窗口内是否含有非噪声点自适应地由小变大。选用5种不同的算法在噪声密度20%~80%范围内进行仿真对比,验证算法的有效性。仿真结果表明,与其它4种算法相比,在低密度噪声时,该算法的峰值信噪比(Peak Signal-to-Noise Ratio, PSNR)和结构相似性指数(Structural Similarity Index, SSIM)优势明显,在80%高密度噪声时仍然保持突出效果,PSNR值至少提高4.26 dB,验证了该算法对高密度椒盐噪声具有更好的滤波性能,很好地保持图像的纹理边缘和细节。

关键词：椒盐噪声图像扩展均值滤波中值滤波迭代自适应加权均值滤波

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Method for C/N ratio estimation using Mask R-CNN and a depth camera for organic fraction of municipal solid wastes

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 222-229页

作者： Jingjing Huang Hongduo Zhang Xu Xiao Jingqi Huang jingxin xie Liang Zhang Heming Hu Sihui Dai Ming Li Yongwei Xu College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China Graduate School of Agricultural and Life Sciences the University of TokyoTokyo 113-0033Japan Hunan Agricultural Equipment Research Institute Changsha 410125China College of Horticulture Hunan Agricultural UniversityChangsha 410128China Center for Spatial Information Science University of TokyoKashiwa 277-8568Japan

Fast assessment of the initial carbon to nitrogen ratio(C/N)of organic fraction of municipal solid waste(OFMSW)is an important prerequisite for automatic composting control to improve efficiency and stability of the bioconversion *** this study,a novel approach was proposed to estimate the C/N of OFMSW,where an instance segmentation model was applied to predict the masks for the waste ***,by combining the instance segmentation model with the depth-camera-based volume calculation algorithm,the volumes occupied by each type of waste were obtained,therefore the C/N could be estimated based on the properties of each type of ***,an instance segmentation dataset including three common classes of OFMSW was built to train mask region-based convolutional neural networks(Mask R-CNN)***,a volume measurement algorithm was proposed,where the measurement result of the object was derived by accumulating the volumes of small rectangular cuboids whose bottom area was calculated with the projection *** the calculated volume was corrected with linear regression *** results showed that the trained instance segmentation model performed well with average precision scores AP_(50)=82.9,AP_(75)=72.5,and mask intersection over unit(Mask IoU)=45.1.A high correlation was found between the estimated C/N and the ground truth with a coefficient of determination R2=0.97 and root mean square error RMSE=*** relative average error was 0.42%and the maximum error was only 1.71%,which indicated this approach has potential for practical applications.

关键词： carbon to nitrogen ratio estimation volume measurement organic fraction of municipal solid waste depth camera instance segmentation

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Occupational Mercury Exposure at a Thermometer Facility-Jiangsu Province, 2019

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China CDC weekly 2020年第42期2卷 827-831,I0001页

作者： Yanqiong Xu Xiaoling Zhang Yiliang Xin Xiaowen Liu Xing Sheng Enmin Ding jingxin xie Lei Han Hengdong Zhang Xin Liu Department of Occupational Disease Prevention and Control Jiangsu Provincial Center for Disease Control and PreventionNanjingJiangsuChina Department of Technique Service Jiangsu Provincial Center for Disease Control and PreventionNanjingJiangsuChina

Summary What is already known about this topic?Mercury is still used in the manufacture of some thermometers in *** may pose health risks if exposure is not properly prevented and *** is added by this report?An onsite investigation of a workplace at a thermometer facility in Jiangsu Province in 2019 found heavily elevated airborne and urinary mercury levels among a massive number of workers exposed to mercury.

关键词： Mercury mercury properly

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