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Nanotechnology and Precision Engineering 2021年第3期4卷 12-19页

作者： huijun xie Yanhua Zou Graduate School of Engineering Utsunomiya University7-1-2YotoUtsunomiyaTochigi 321-8585Japan

A magnetic abrasive finishing process using an alternating magnetic field is proposed for the finishing of complex *** an alternating field,the periodic changes in current will cause the magnetic cluster used as a magnetic brush to fluctuate,which will not only continuously replace the abrasive particles in contact with the workpiece,but also periodically adjust the shape of the magnetic cluster to better fit the surface of the *** this paper,the influence of a combination of alternating and static magnetic fields on the magnetic field in the finishing area is *** feasibility of this process for finishing micro-grooves is *** and experimental measurements show that the combination of alternating and static magnetic fields can retain the advantages of the alternating field while increasing the magnetic flux density in the finishing *** experimental results show that the process is feasible for finishing micro-grooves,with an excellent deburring effect on the groove edges.

关键词： Alternating magnetic field Complex surface Deburring Magnetic abrasive finishing Micro-groove

Sorption removal of cephalexin by HNO_3 and H_2O_2 oxidized activated carbons

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Science China Chemistry 2012年第9期55卷 1959-1967页

作者： LIU WeiFeng xie huijun ZHANG Jian ZHANG ChengLu Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityJinan 250100China Environment Research Institute Shandong UniversityJinan 250100China

Cephalexin＇s traces within pharmaceutical effluents have toxic impact toward ecological and human health. Low-cost activated carbon derived from Trapa natans husk was oxidized with hydrogen peroxide and nitric acid, and tested for their ability to re- move cephalexin from aqueous solutions. Oxidization with H202 showed negative effect on the cephalexin sorption, whereas HNO3 oxidization improved the adsorption. The cephalexin adsorption isotherms on the native and HNO3 oxidized carbons correlated well with the Freundlich equation while their kinetics followed the pseudo-second order model. The removal of cephalexin by the native and HNO3 oxidized carbons was found to be most favored at low ionic strength and strong acidic conditions. Based on the thermal and FTIR analyses, the interaction mechanisms of the interaction between cephalexin and the carbons were proposed. Electrostatic attraction, hydrophobic interaction and chemical bonding with surface functional groups were demonstrated as primary mechanisms for cephalexin removal. The nitrogen functionalities on the carbon surface were considered to be an important factor affecting the adsorption process.

关键词： cephalexin activated carbon oxidation adsorption mechanism

近20年中国西南地区植被碳利用率时空变化特征及驱动因素

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气候与环境研究 2024年第3期29卷 267-280页

作者：杨正兰冯雨实张廷斌吴欢张彩谢慧君李建重庆城市职业学院建筑工程学院重庆402160 成都理工大学地球与行星科学学院成都610059 国家环境保护水土污染协同控制与联合修复重点实验室(成都理工大学) 成都610059 重庆市地质矿产勘查开发局南江水文地质工程地质队重庆401121 重庆工程职业技术学院测绘地理信息学院重庆402260

植被碳利用率作为生物圈与大气圈碳循环的关键参数之一,对了解生态系统碳源和碳汇具有重要作用。本文基于MOD17A2H数据,采用Theil-Sen media趋势分析、空间插值以及偏相关分析法,分析2001~2020年西南地区植被碳利用率(Carbon Use Effici... 详细信息

植被碳利用率作为生物圈与大气圈碳循环的关键参数之一,对了解生态系统碳源和碳汇具有重要作用。本文基于MOD17A2H数据,采用Theil-Sen media趋势分析、空间插值以及偏相关分析法,分析2001~2020年西南地区植被碳利用率(Carbon Use Efficiency,CUE)时空分布格局及变化趋势,根据气象数据和数字高程模型(Digital Elevation Model,DEM)数据,重点研究了西南地区植被CUE对气候变化的响应。结果表明:(1)2001~2020年西南地区不同植被类型年内CUE整体呈上升—下降—再上升—再下降的变化特征,整体上各植被类型CUE呈下降趋势,下降速率依次为:灌木>森林>草地>农作物。(2)近20年西南地区植被CUE多年均值约为0.75,植被固碳能力较强,空间上表现出由南部和东北部向西北部递增的空间分布格局,趋势分析表明西南地区植被CUE整体表现为微弱下降趋势。(3)2001~2020年西南地区植被碳利用率与气温、降水以及日照时长均呈负相关关系,整体上西南地区植被CUE主要受气温和日照时长影响,其次为降水。

关键词： MODIS 植被碳利用率(CUE) 时空变化气候因子西南地区

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Sorption of norfloxacin from aqueous solutions by activated carbon developed from Trapa natans husk

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Science China Chemistry 2011年第5期54卷 835-843页

作者： xie huijun LIU WeiFeng ZHANG Jian ZHANG ChengLu REN Liang Environment Research Institute Shandong UniversityJinan 250100China Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong UniversityJinan 250100China

The low-cost activated carbon was prepared from a renewable aquatic plant residue,Trapa natans husk,and tested for its ability to remove norfloxacin (NOR) from aqueous solutions. Physical and chemical properties of the Trapa natans husk activated carbon (TAC) were characterized. TAC has a large surface area of 1274 m2/g and mesoporous structure. Carboxylic and hydroxyl groups contributed to the sorption of NOR onto TAC but they were not the most important factors in the sorption process. The rates of adsorption followed the pseudo-second-order kinetics and the overall rate of NOR uptake was controlled by both external mass transfer and intro particle diffusion during the entire adsorption period. The equilibrium data fitted well with the Freundlich and Tempkin models and the sorption was found to be a favorable process. The adsorption of NOR by TAC was strongly dependent on the solution pH. Electrostatic interaction and hydrophobic interaction were proposed to be the principal NOR sorption mechanism.

关键词： norfloxacin Trapa natans husk activated carbon adsorption kinetic and isotherms

Relationships of nitrous oxide fluxes with water quality parameters in free water surface constructed wetlands

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Frontiers of Environmental Science & Engineering 2009年第2期3卷 241-247页

作者： Juan WU Jian ZHANG Wenlin JIA huijun xie Bo ZHANG School of Environmental Science&Engineering Shandong UniversityJinan 250100China College of Resources&Environment Qingdao Agricultural UniversityQingdao 266109China Environment Research Institute Shandong UniversityJinan 250100China

The effects of chemical oxygen demand(COD)concentration in the influent on nitrous oxide(N_(2)O)emissions,together with the relationships between N_(2)O and water quality parameters in free water surface constructed wetlands,were investigated with laboratoryscale systems.N_(2)O emission and purification performance of wastewater were very strongly dependent on COD concentration in the influent,and the total N_(2)O emission in the system with middle COD influent concentration was the *** relationships between N_(2)O and the chemical and physical water quality variables were studied by using principal component scores in multiple linear regression analysis to predict N_(2)O *** multiple linear regression model against principal components indicated that different water parameters affected N_(2)O flux with different COD concentrations in the influent,but nitrate nitrogen affected N_(2)O flux in all systems.

关键词： free water surface constructed wetland nitrous oxide emission water quality parameter principal component analysis multiple linear regression

Substrate-induced changes in microbial community-level physiological profiles and their application to discriminate soil microbial communities

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Journal of Environmental Sciences 2008年第6期20卷 725-731页

作者： CHEN Jian xie huijun ZHUANG Xuliang ZHUANG Guoqiang BAI Zhihui ZHANG Hongxun Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Bureau of Science and Technology for Resources and Environment Chinese Academy of Sciences Beijing 100864 China

The addition of simple substrates could affect the microbial respiration in soils. This substrate-induced respiration is widely used to estimate the soil microbial biomass, but little attention has been paid to its influence on the changes of community-level physiological profiles. In this study, the process of microbial communities responding to the added substrate using sole-carbon-source utilization （BIOLOG） was investigated. BIOLOG is biased toward fast-growing bacteria; this advantage was taken to detect the prompt response of the active microbial communities to the added substrate. Four soil samples from agricultural fields adjacent to heavy metal mines were amended with L-arginine, citric acid, or D-glucose. Substrate amendments could, generally, not only increase the metabolic activity of the microbial communities, but also change the metabolic diverse patterns compared with no-substrate control. By tracking the process, it was found that the variance between substrate-induced treatment and control fluctuated greatly during the incubation course, and the influences of these three substrates were different. In addition, the application of these induced changes to discriminate soil microbial communities was tested. The distance among all samples was greatly increased, which further showed the functional variance among microbial communities in soils. This can be very useful in the discrimination of microbial communities even with high similarity.

关键词： substrate-induced respiration (SIR) BIOLOG community-level physiological profiles (CLPPs)

人工智能辅助系统在宫颈薄层液基细胞学研究中的应用

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浙江医学 2024年第2期46卷 177-181页

作者：王凯怡赵亚丹谢慧君邓再兴湖州市妇幼保健院妇产科 313000 湖州市妇幼保健院病理科 313000

目的探讨人工智能(AI)辅助系统在宫颈薄层液基细胞学研究中的应用。方法收集2022年7月至2023年2月湖州市妇幼保健院的1994例宫颈薄层液基细胞学涂片样本。以阴道镜活检结果宫颈上皮内病变(CIN)1级及以上(≥CIN 1级)为金标准,分别采用人... 详细信息

目的探讨人工智能(AI)辅助系统在宫颈薄层液基细胞学研究中的应用。方法收集2022年7月至2023年2月湖州市妇幼保健院的1994例宫颈薄层液基细胞学涂片样本。以阴道镜活检结果宫颈上皮内病变(CIN)1级及以上(≥CIN 1级)为金标准,分别采用人工阅片、AI阅片和AI辅助系统阅片(AI辅助阅片)3种方式对宫颈细胞学液基薄层涂片进行阅片。比较不同宫颈薄层液基细胞学检测(TCT)结果下不同年龄段样本3种阅片方式阳性率、灵敏度和特异度以及3种阅片方式的阅片时长。结果1994例样本中,活检结果≥CIN 1级共102例,总体阳性率为5.12%,TCT结果为意义不明的非典型鳞状细胞(ASCUS)及以上(≥ASC-US)的阳性率为9.63%,低度鳞状上皮内病变(LSIL)及以上(≥LSIL)的阳性率为4.91%。TCT结果≥ASC-US时,≥30岁组样本AI阅片阳性率高于18~29岁组,差异有统计学意义(P0.05)。TCT结果≥LSIL时,18~29岁和30岁组人工阅片、AI阅片和AI辅助阅片阳性率比较差异均无统计学意义(均P>0.05)。TCT结果≥ASC-US时,人工阅片的灵敏度及特异度分别为100.00%、95.30%,AI辅助阅片的灵敏度及特异度分别为95.10%、94.66%,两种阅片方式的灵敏度、特异度比较差异均无统计学意义(均P>0.05)。TCT结果≥LSIL时,人工阅片的灵敏度及特异度分别为66.67%、98.78%,AI辅助阅片的灵敏度及特异度分别为82.35%、97.15%,AI辅助阅片的灵敏度高于人工阅片,差异有统计学意义(P0.05)。与人工阅片比较,AI辅助阅片的总阅片时长减少25.34 h,总阅片时长减少率为50.76%(25.34/49.92);平均每张涂片减少45.75 s,平均阅片时长减少率为50.77%(45.75/90.12)。结论病理医师运用AI辅助系统进行宫颈癌变筛查时,可以保证阅片准确度,提高细胞学阅片效率。

关键词：宫颈癌人工智能细胞学阴道镜检查

Hovering rotor aerodynamics in extreme ground effect

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Chinese Journal of Aeronautics 2024年第7期37卷 204-219页

作者： Zhenlong WU Tianyu ZHANG huijun TAN Haoyu ZHOU Wei CHEN Maixiang xie College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China China Aviation Power Machinery Research Institute Zhuzhou 412002China

This paper presents an experimental and numerical study of the aerodynamics of a moderate-scale rotor hovering in the Extreme Ground Effect(EGE)where rotor height-offground is below half the rotor *** tip vortex field was visualized by using the PIV *** aerodynamic performance,tip vortex trajectory,wall jet characteristics,surface pressure and velocity fields were measured and *** explore more deeply the flow mechanisms of the extreme ground effect,Detached Eddy Simulation(DES)was conducted on completely structured *** results showed significant deviations of the rotor performance in EGE from that in Regular Ground Effect(RGE)with the rotor heights of more than half the rotor ***,the flow structures of the rotor in EGE are considerably complex,such as the wall jet and groundwash flow *** rotor wake flow and tip vortices impact the ground more frequently,resulting in distinctive characteristics of the surface pressure and velocity fields in EGE.

关键词： Rotor Ground effect Tip vortex Detached Eddy Simulation(DES) Groundwash

Advanced modeling of the absorption enhancement of black carbon particles in chamber experiments by considering the morphology and coating thickness

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Frontiers of Environmental Science & Engineering 2024年第9期18卷 129-142页

作者： Xiaodong Wei Jianlin Hu Chao Liu Xiaodong xie Junjie Yin Song Guo Min Hu Jianfei Peng huijun Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological Disaster(Ministry of Education)Nanjing University of Information Science and TechnologyNanjing 210044China Nansen−Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China East China Air Traffic Management Bureau CAAC Shanghai 200335China State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution Control(IJRC)(Ministry of Education)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Tianjin Key Laboratory of Urban Transport Emission Research&State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300071China

Measurements studies have shown that the absorption of radiation by black carbon(BC)increases as the particles ***,there are significant discrepancies between the measured and modeled absorption enhancement(E_(abs)),largely due to the simplifications used in modeling the mixing states and shape *** took advantage of chamber experiments on BC aging and developed an efficient method to resolve the particle shape based on the relationship between the coating fraction(ΔD_(ve)/D_(ve),0)and fractal dimension(D_(f)),which can also reflect the variations of D_(f)during the whole BC aging *** with externally and partly mixed states(0≤ΔD_(ve)/D_(ve),0≤0.5)can be considered to be uniformly distributed with the D_(f)values of 1.8–2.1,whereas the Df values are constrained in the range 2.2–2.8 for fully mixed states(ΔD_(ve)/D_(ve),0>0.5).The morphological parameters(i.e.,the effective density and the dynamic shape factor)were compared with the measured values to verify the simulated *** simulated mean deviations of morphological parameters were smaller than 8%for the method resolving the particle *** applying a realistic shape and refractive index,the mass absorption cross for fully mixed states can be improved by 11%compared with a simplified core–shell *** on our understanding of the influence of D_(f)andΔD_(ve)/D_(ve),0 on E_(abs),we propose a two-stage calibration equation to correct the E_(abs)values estimated by the core–shell model,which reduces the simulation error in the Mie calculation by 6%–14%.

关键词： Black carbon Mixing states Fractal dimension Dynamic shape factor Absorption enhancement

The gene encoding flavonol synthase contributes to lesion mimic in wheat

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The Crop Journal 2024年第3期12卷 814-825页

作者： Tingting Dong Hongchun Xiong huijun Guo Yongdun xie Linshu Zhao Jiayu Gu Huiyuan Li Shirong Zhao Yuping Ding Xiyun Song Luxiang Liu College of Life Sciences Key Laboratory of Major Crop Germplasm Innovation and Application in QingdaoQingdao Agricultural UniversityQingdao 266109ShandongChina State Key Laboratory of Crop Gene Resources and Breeding/National Engineering Laboratory of Crop Molecular Breeding/CAEA Research and Development Centre on Nuclear Technology Applications for Irradiation Mutation Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease *** this,only a few lesion mimic genes have been identified in *** this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in *** Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome *** gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb *** this region,we identified 16 high-confidence genes,with only two displaying mutations in ***,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression *** phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for *** sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis ***,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the *** to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the *** investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat.

关键词： Lesion mimic mutant Wheat Gene mapping Flavonol synthase gene Flavonoid