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Monthly composites from Sentinel-1 and Sentinel-2 images for regional major crop mapping with Google Earth Engine

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Journal of Integrative Agriculture 2021年第7期20卷 1944-1957页

作者： LUO Chong liu Huan-jun LU Lii-ping liu zheng-rong KONG Fan-chang ZHANG Xin-le Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102P.R.China School of Public Adminstration and Law Northeast Agricultural UniversityHarbin 150030P.R.China

Rapid and accurate access to large-scale,high-resolution crop-type distribution maps is important for agricultural management and sustainable agricultural *** to the limitations of remote sensing image quality and data processing capabilities,large-scale crop classification is still *** study aimed to map the distribution of crops in Heilongjiang Province using Google Earth Engine(GEE)and Sentinel-1 and Sentinel-2 *** obtained Sentinel-1 and Sentinel-2 images from all the covered study areas in the critical period for crop growth in 2018(May to September),combined monthly composite images of reflectance bands,vegetation indices and polarization bands as input features,and then performed crop classification using a Random Forest(RF)*** results show that the Sentinel-1 and Sentinel-2 monthly composite images combined with the RF classifier can accurately generate the crop distribution map of the study area,and the overall accuracy(OA)reached 89.75%.Through experiments,we also found that the classification performance using time-series images is significantly better than that using single-period *** with the use of traditional bands only(i.e.,the visible and near-infrared bands),the addition of shortwave infrared bands can improve the accuracy of crop classification most significantly,followed by the addition of red-edge *** common vegetation indices and Sentinel-1 data to the crop classification improved the overall classification accuracy and the OA by 0.2 and 0.6%,respectively,compared to using only the Sentinel-2 reflectance *** analysis of timeliness revealed that when the July image is available,the increase in the accuracy of crop classification is the *** the Sentinel-1 and Sentinel-2 images for May,June,and July are available,an OA greater than 80%can be *** results of this study are applicable to large-scale,high-resolution crop classification and provide key technologies f

关键词： Sentinel-1 Sentinel-2 monthly composites crop mapping Google Earth Engine

Removal of arsenic from water by silver nanoparticles and Fe-Ce mixed oxide supported on polymeric anion exchanger

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Journal of Environmental Sciences 2025年第5期151卷 540-549页

作者： Li Li Su-juan Yu rong-gang zheng Qing-cun Li Rui liu Jing-fu liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China University of Chinese Academy of Sciences Beijing 100049China Department of Ecology and Resources Engineering He Tao CollegeInner Mongolia 015000China

By encapsulating nanoscale particles of goethite(α-FeO(OH)),hydrous ceric oxide(CeO_(2)·H_(2)O,HCO)and silver nanoparticles(AgNPs)in the pores of polystyrene anion exchanger D201,a novel nanocomposite FeO(OH)-HCO-Ag-D201 was prepared for the effective removal of arsenic from *** isotherm study shows that FeO(OH)-HCO-Ag-D201 has excellent adsorption performance for As(III)and As(V),with an increased adsorption capacity of As(III)to 40.12 mg/g compared to that of 22.03 mg/g by the composite adsorbent without AgNPs(FeO(OH)-HCO-D201).The adsorption kinetics data showed that the sorption rate of FeO(OH)-HCO-Ag-D201 for As(III)is less than that for As(V),and the adsorption of As(III)and As(V)were consistent with the pseudo-second-order model and the pseudofirst-order model,*** or basic conditions are favored for the adsorption of As(III/V)by FeO(OH)-*** with nitrate/chloride/bicarbonate,sulfate/silicate/phosphate showed more remarkable inhibition of arsenic removal by FeO(OH)-HCO-Ag-D201,whereas natural organic matter showed no interference to the arsenic *** As(V)adsorption involved different interactions such as electrostatic attraction and surface complexation,while the adsorption of As(III)involved the part oxidization of As(III)to As(V)and the simultaneous adsorption of As(III)and As(V).In addition to the Ce(IV)in CeO_(2)·H_(2)O acted as an oxidant,the synergistic effect ofα-FeO(OH)and AgNPs also contributed to the oxidization of As(III)to As(V).Moreover,the reusable property suggested that this FeO(OH)-HCO-Ag-D201 nanocomposite has great potential for arsenic-contaminated water purification.

关键词： FeO(OH)-HCO-Ag-D201 Arsenic removal Synergistic effect Oxidation Electrostatic attraction Surface complexation

Foliar-applied zinc promotes cadmium allocation from leaf surfaces to grains in rice

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Journal of Environmental Sciences 2025年第5期151卷 582-593页

作者： Ya-Ting liu Bo-Fang Yan Xuan Cai Hong-Xiang zheng rong-Liang Qiu Ye-Tao Tang School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Institute of Facility Agriculture Guangdong Academy of Agricultural SciencesGuangzhou 510640China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology Sun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China

The accumulation of Cd by rice poses significant health *** fertilizationwith Zn can reduce grain Cd contents in rice grown in Cd-contaminated ***,atmospheric deposition on leaves is another vector of Cd contamination,and it remains unclear how Zn application affects the allocation of such *** conducted an experiment where the flag leaves of rice plants were treated with solutions with various Zn concentrations and a constant Cd *** 111Cd stable isotope was used to trace the flux of foliarapplied *** levels of foliar-applied Zn enhanced Cd efflux and grain *** is attributed to limited sequestration of foliar-applied Cd in the leaf cell symplasm and increased Cd desorption from leaf cell walls when a high Zn^(2+)concentration occurs in the *** Zn oxide nanoparticlesmitigated these ***,the expressions of OsLCT1 and OsZIP7 in flag leaves and OsHMA2 and OsZIP7 in the uppermost nodes were upregulated under high-Zn^(2+)treatment,which may facilitate Cd phloem loading and grain *** is advised in using foliar Zn in areas with high atmospheric Cd due to potential grain-contamination risks.

关键词： Atmospheric deposition Isotope labelling Metal interaction Phloem Cell wall

基于量子加密技术的集中型馈线自动化在20kV电网中的应用研究

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机电产品开发与创新 2025年第1期38卷 65-68页

作者：廖平军刘荣峥国网浙江省电力有限公司桐乡市供电公司浙江桐乡314500 国网江西省电力有限公司供电服务管理中心江西南昌330000

新时期,“用好电”成为人民追求美好生活新的意愿,传统单一的继电保护或者馈线自动化无法满足“供好电”要求。根据桐乡20kV配电网网架、设备以及故障特性等入手,减少分支线故障对主线影响,提升干线故障快速隔离及恢复。提出了支线或者... 详细信息

新时期,“用好电”成为人民追求美好生活新的意愿,传统单一的继电保护或者馈线自动化无法满足“供好电”要求。根据桐乡20kV配电网网架、设备以及故障特性等入手,减少分支线故障对主线影响,提升干线故障快速隔离及恢复。提出了支线或者环网柜出线保护与变电所出线开关保护极差配合,快速切除支线故障,主干线配置“三遥” 4G+量子开关或环网柜站所“三遥” DTU,大用户及大分支线配置“二遥”智能开关,主干线覆盖全自动FA助力配网秒级复电,保障电力系统安全稳定运行和社会经济高质量发展。

关键词：馈线自动化继电保护量子开关智能开关可靠性

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KdV方程和mKdV方程的新奇异解(英文)

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华南理工大学学报（自然科学版） 2012年第10期40卷 96-101页

作者：刘正荣唐昊华南理工大学数学系广东广州510640

研究了著名的KdV方程和mKdV方程的奇异解.首先,建立了与这两个方程相应的平面行波系统.然后,利用行波系统的一些特殊轨道,导出了新奇异解.最后,通过mKdV方程的奇异解以及Miura变换,获得了KdV方程其它的新奇异解.

关键词： KdV方程 mKdV方程奇异解 Miura变换

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基于俯仰频率分集技术的波束形成方法

电子与信息学报 2016年第12期38卷 3070-3077页

作者：吴旭姿刘峥谢荣西安电子科技大学雷达信号处理国家重点实验室西安710071

传统频率分集阵列雷达在水平阵元间引入线性频率偏差,其波束在方位维与距离维具有耦合性,且存在栅瓣。针对此问题,该文提出一种基于俯仰频率分集技术的波束形成方法。首先建立俯仰频率分集阵列雷达信号模型,详细分析了发射方向图的时间... 详细信息

传统频率分集阵列雷达在水平阵元间引入线性频率偏差,其波束在方位维与距离维具有耦合性,且存在栅瓣。针对此问题,该文提出一种基于俯仰频率分集技术的波束形成方法。首先建立俯仰频率分集阵列雷达信号模型,详细分析了发射方向图的时间依赖性和栅瓣特性。然后通过设计接收端的阵元参数,合成无栅瓣的发射-接收方向图。仿真实验验证了所提方法的有效性,所得波束在距离维与方位维无耦合,且主瓣宽度较窄。

关键词：相控阵雷达波束形成俯仰频率分集

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非正侧阵雷达距离模糊杂波抑制新方法

西安电子科技大学学报 2017年第2期44卷 1-7页

作者：吴旭姿刘峥谢荣西安电子科技大学雷达信号处理国家重点实验室

为了改善严重距离模糊情况下雷达对地面强杂波的抑制性能,提出了一种基于频率分集技术的杂波抑制方法.首先,推导了非正侧阵频率分集雷达空时信号模型,在此基础上,给出了频率增量的设计准则用来区分距离模糊杂波以及防止回波信号去相关.... 详细信息

为了改善严重距离模糊情况下雷达对地面强杂波的抑制性能,提出了一种基于频率分集技术的杂波抑制方法.首先,推导了非正侧阵频率分集雷达空时信号模型,在此基础上,给出了频率增量的设计准则用来区分距离模糊杂波以及防止回波信号去相关.然后,利用子空间投影算法抑制距离模糊杂波.仿真试验证明了该方法的有效性,在俯仰维自由度有限的情况下,该方法的性能优于传统俯仰滤波方法.

关键词：机载雷达杂波抑制频率分集距离模糊

An efficient conversion model between acceleration and pseudo-acceleration response spectra considering effects of magnitude,distance,and site class

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 15-30页

作者： liu zheng Zhao Yan-Gang Zhang Haizhong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China Faculty of Agriculture Yamagata University1-23Wakaba-machiTsuruoka-shiYamagata 997-8555Japan

Both acceleration and pseudo-acceleration response spectra play important roles in structural seismic ***,only one of them is generally provided in most seismic ***,many studies have attempted to develop conversion models between the acceleration response spectrum(SA)and the pseudo-acceleration response spectrum(PSA).Our previous studies found that the relationship between SA and PSA is affected by magnitude,distance,and site ***,we developed an SA/PSA model incorporating these ***,this model is suitable for cases with small and moderate magnitudes and its accuracy is not good enough for cases with large *** paper aims to develop an efficient SA/PSA model by considering influences of magnitude,distance,and site class,which can be applied to cases not only with small or moderate magnitudes but also with large *** this purpose,regression analyses were conducted using 16,660 horizontal seismic records with a wider range of *** magnitude of these seismic records varies from 4 to 9 and the distances vary from 10 to 200 *** ground motions were recorded at 338 stations covering four site *** comparing them with existing models,it was found that the proposed model shows better accuracy for cases with any magnitudes,distances,and site classes considered in this study.

关键词： acceleration response spectrum pseudo-acceleration response spectrum magnitude distance site class

来氟米特联合激素治疗难治性IgA肾病的临床观察

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南方医科大学学报 2007年第6期27卷 893-894,899页

作者：荣乐刘郑荣南方医科大学南方医院肾内科广东广州510515

目的观察应用来氟米特联合激素治疗难治性IgA肾病的疗效和安全性。方法收集2005年4月至2006年5月南方医院肾内科符合条件的13例IgA肾病患者接受来氟米特联合激素治疗,观察治疗前和治疗后2、4、8、12、16、20、24周的相关临床指标变化,... 详细信息

目的观察应用来氟米特联合激素治疗难治性IgA肾病的疗效和安全性。方法收集2005年4月至2006年5月南方医院肾内科符合条件的13例IgA肾病患者接受来氟米特联合激素治疗,观察治疗前和治疗后2、4、8、12、16、20、24周的相关临床指标变化,并进行评价。结果与加用来氟米特前比,联合治疗后,1、3、6个月24h尿蛋白定量均有下降(P0.05)。不良反应较轻,病人耐受性良好。结论来氟米特联合激素方案可以作为治疗难治性IgA肾病的选择之一,且安全、有效。

关键词：来氟米特 IgA肾病激素