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QuEChERS-高效液相色谱法测定土壤中嘧霉胺和吡唑醚菌酯残留

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农药 2017年第8期56卷 596-599页

作者：李艳滕应赵玲刘方任文杰马文亭贵州大学资源与环境工程学院贵阳550025 中国科学院土壤环境与污染修复重点实验室南京土壤研究所南京210008

[目的]建立一种QuEChERS样品前处理联合高效液相色谱-二极管阵列(HPLC-PDA)同时测定土壤中嘧霉胺和吡唑醚菌酯残留量的分析方法。[方法]采用QuEChERS方法对土壤样品进行前处理,以乙腈作为提取剂,PSA+C18+无水Mg SO4净化,HPLC-PDA检测,... 详细信息

[目的]建立一种QuEChERS样品前处理联合高效液相色谱-二极管阵列(HPLC-PDA)同时测定土壤中嘧霉胺和吡唑醚菌酯残留量的分析方法。[方法]采用QuEChERS方法对土壤样品进行前处理,以乙腈作为提取剂,PSA+C18+无水Mg SO4净化,HPLC-PDA检测,外标法定量。[结果]嘧霉胺和吡唑醚菌酯的最低检出限分别为6.2、12.8μg/L,定量限分别为19.6、37.7μg/L,在3个农药添加水平下(100、400、800μg/kg)嘧霉胺及吡唑醚菌酯的回收率范围为86.3%~99.2%,相对标准偏差为2.0%~5.4%。[结论]该方法准确、快速、方便,适用于土壤中嘧霉胺、吡唑醚菌酯这2种杀菌剂农药的残留检测。

关键词：嘧霉胺吡唑醚菌酯 QuEChERS 高效液相色谱土壤

高等职业教育计算机专业应用型创新人才培养研究

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电脑知识与技术 2010年第23期6卷 6563-6565页

作者：赵小丽任文杰河南农业职业学院

高等职业教育旨在培养高素质的应用型人才,培养学生综合素质与自主创新能力。计算机专业作为科技发展的带头专业,要为社会培养出能够真正做到把技术应用到实际,在实际工作中做到有创新的应用型创新人才。

关键词：高等职业教育计算机专业应用型创新人才产学研结合

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基于多级中值滤波的小波去噪方法

计算机应用 2007年第9期27卷 2117-2119,2125页

作者：贺长伟刘英霞任文杰王欣山东大学信息科学与工程学院

经典图像去噪方法中,多级中值滤波有良好的保护细节的特性,近年来在小波域中对信号的处理,能使噪声抑制更加有效。结合两者的特点,提出了基于多级中值滤波的改进算法,利用最大最小中值之差判断平坦及边缘区域,实现了在小波域中平滑噪声... 详细信息

经典图像去噪方法中,多级中值滤波有良好的保护细节的特性,近年来在小波域中对信号的处理,能使噪声抑制更加有效。结合两者的特点,提出了基于多级中值滤波的改进算法,利用最大最小中值之差判断平坦及边缘区域,实现了在小波域中平滑噪声的同时还可以保护图像细节不受损失。实验表明该方法与Donoho的软门限方法相比较,可以得到更好的去噪效果。

关键词：小波变换图像去噪多级中值滤波最佳估计

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基于加权最大类间边缘准则的人脸识别

计算机工程 2008年第15期34卷 193-195页

作者：秦春霞任文杰贺长伟王欣山东大学信息科学与工程学院济南250100

在人脸识别中,特征提取技术被广泛应用于减少数据量和增强数据可分性。该文依据最大类间边缘准则,提出一种加权最大类间边缘准则的特征提取方法,引入加权函数,对类内和类间散布矩阵分别进行加权。并设计了一个基于离散小波分解、主成分... 详细信息

在人脸识别中,特征提取技术被广泛应用于减少数据量和增强数据可分性。该文依据最大类间边缘准则,提出一种加权最大类间边缘准则的特征提取方法,引入加权函数,对类内和类间散布矩阵分别进行加权。并设计了一个基于离散小波分解、主成分分析和加权最大类间边缘准则的人脸识别系统。在ORL人脸库上的测试结果证实,该方法提高了识别率,最高识别率达98.25%。

关键词：人脸识别特征提取加权最大类间边缘准则

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang wen-jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

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Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li wen Yi XiangHui Xue jie Zeng HaiLun Ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

四通道色谱分离仪净化/气相色谱-质谱法测定烟叶中的多环芳烃

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分析测试学报 2016年第8期35卷 968-973页

作者：马军滕应陆引罡甘信宏任文杰马文亭贵州大学农学院贵州贵阳550025 中国科学院南京土壤研究所土壤环境与污染修复重点实验室江苏南京210008 铜仁学院材料与化学工程学院贵州铜仁554300

建立了同时检测新鲜烟叶中16种多环芳烃（PAHs）的四通道色谱分离仪净化/气相色谱-质谱（GC-MS）分析方法。样品经二氯甲烷索氏提取,四通道色谱分离仪净化,GC-MS选择离子监测模式（SIM）测定和外标法定量,重点考察了新鲜烟叶提取液的分... 详细信息

建立了同时检测新鲜烟叶中16种多环芳烃（PAHs）的四通道色谱分离仪净化/气相色谱-质谱（GC-MS）分析方法。样品经二氯甲烷索氏提取,四通道色谱分离仪净化,GC-MS选择离子监测模式（SIM）测定和外标法定量,重点考察了新鲜烟叶提取液的分离净化条件。结果表明：16种PAHs类化合物在10～1 000μg/kg范围内定量离子的峰面积与质量浓度呈较好的线性关系（r〉0.99）。仪器检出限（LOD）为0.35～1.75μg/kg,方法检出限（MDLs）为1.01～2.87μg/kg。在10,50,200μg/kg 3个浓度水平下的加标回收率为81.0%～107.8%,相对标准偏差（RSD,n=6）为2.7%～8.0%。该方法简便、快捷、可操作性强、应用范围广,适合于烟草等作物中PAHs类化合物的分析检测。

关键词：四通道色谱分离仪气相色谱-质谱多环芳烃净化烟叶

江西省大米中黄曲霉毒素B_1分析及膳食暴露评估

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食品科技 2015年第3期40卷 315-319页

作者：唐笑任文洁陈波许杨李燕萍南昌大学食品科学与技术国家重点实验室南昌330047 中德联合研究院南昌330047

目的：分析江西省大米中黄曲霉毒素B1含量水平,并对该地区人群通过膳食暴露黄曲霉毒素B1的进行初步风险评估。方法：在2013-2014年期间,随机采集了517份大米样品,采用酶联免疫吸附法检测黄曲霉毒素B1,并且使用@Risk软件对一般消费人群... 详细信息

目的：分析江西省大米中黄曲霉毒素B1含量水平,并对该地区人群通过膳食暴露黄曲霉毒素B1的进行初步风险评估。方法：在2013-2014年期间,随机采集了517份大米样品,采用酶联免疫吸附法检测黄曲霉毒素B1,并且使用@Risk软件对一般消费人群和高消费人群通过膳食途径暴露黄曲霉毒素B1进行风险评估。结果：所有大米样品均未超过我国现行大米中黄曲霉毒素B1限量标准。通过蒙特卡罗模拟,2-6岁儿童、标准人、城市标准人、农村标准人中食用大米在高消费情况下对黄曲霉毒素B1贡献的P99百分位值（90%置信区间）分别为86.16（74.19-102.91）、34.54（29.74-41.25）、28.85（24.84-34.46）、36.32（31.27-43.38）ng/（kgbw·d）,可能引发原发性肝癌的风险分别为2.671（2.300-3.190）、1.071（0.922-1.279）、0.894（0.770-1.068）、1.126（0.969-1.345）例/（10万人·年）。结论：江西省总体人群大米中黄曲霉毒素B1膳食暴露风险不大,但2-6岁儿童具有潜在风险,需要引起重视。

关键词：黄曲霉毒素B1 膳食暴露风险评估蒙特卡罗

Sulfolane‑Based Flame‑Retardant Electrolyte for High‑Voltage Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 498-516页

作者： Xuanlong He jie Peng Qingyun Lin Meng Li Weibin Chen Pei Liu Tao Huang Zhencheng Huang Yuying Liu Jiaojiao Deng Shenghua Ye Xuming Yang Xiangzhong ren Xiaoping Ouyang Jianhong Liu Biwei Xiao Jiangtao Hu Qianling Zhang Graphene Composite Research Center College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Center of Electron Microscopy State Key Laboratory of Silicon and Advanced Semiconductor MaterialsSchool of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China GRINM(Guangdong)Research Institute for Advanced Materials and Technology FoshanGuangdong 528051People’s Republic of China College of Energy Engineering Zhejiang UniversityHangzhouZhejiang 310027People’s Republic of China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105People’s Republic of China Shenzhen Eigen-Equation Graphene Technology Co.Ltd Shenzhen 518000People’s Republic of China

Sodium-ion batteries hold great promise as next-generation energy storage ***,the high instability of the electrode/electrolyte interphase during cycling has seriously hindered the development of *** particular,an unstable cathode–electrolyte interphase(CEI)leads to successive electrolyte side reactions,transition metal leaching and rapid capacity decay,which tends to be exacerbated under high-voltage ***,constructing dense and stable CEIs are crucial for high-performance *** work reports localized high-concentration electrolyte by incorporating a highly oxidation-resistant sulfolane solvent with non-solvent diluent 1H,1H,5H-octafluoropentyl-1,1,2,2-tetrafluoroethyl ether,which exhibited excellent oxidative stability and was able to form thin,dense and homogeneous *** excellent CEI enabled the O3-type layered oxide cathode NaNi_(1/3)Mn_(1/3)Fe_(1/3)O_(2)(NaNMF)to achieve stable cycling,with a capacity retention of 79.48%after 300 cycles at 1 C and 81.15%after 400 cycles at 2 C with a high charging voltage of 4.2 *** addition,its nonflammable nature enhances the safety of *** work provides a viable pathway for the application of sulfolane-based electrolytes on SIBs and the design of next-generation high-voltage electrolytes.

关键词： Sodium-ion batteries Sulfolane-based electrolyte High voltage Layered oxide cathode Flame retardant