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Groundwater Contamination with NO_3-N in a Wheat-Corn Cropping System in the North China Plain

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Pedosphere 2007年第6期17卷 721-731页

作者： ZHAO Bing-Zi ZHANG Jia-Bao m. FLURY ZHU An-Ning JIANG Qi-Ao BI Jin-Wei State Experimental Station for Agra-Ecology State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Department of Crop and Soil Sciences Center for Multiphase Environmental Research Washington State University Pullman WA 99164 （USA）

The North China Plain,where summer corn(Zea mays L.)and winter wheat(Triticum aestivum L.)are the major crops grown,is a major agricultural area in *** soils make the region susceptible to groundwater pollution by NO_3-N,which is applied to fields in large amounts of more than 400 kg NO_3-N ha^(-1)as fertilizer.A field experiment was established in 2002 to examine the relationship among N fertilization rate,soil NO_3-N,and NO_3-N groundwater *** adjacent fields were fertilized with local farmers' N fertilization rate(LN)and double the normal application rate(HN),respectively,and managed under otherwise identical *** fields were under a traditional summer corn/winter wheat *** a 22-month period,we monitored NO_3-N concentrations in both bulk soil and soil pore water in 20-40 cm increments up to 180 cm *** also monitored NO_3-N concentrations in groundwater and the depth of the groundwater *** significant differences in soil NO_3-N were observed between the LN and HN *** identified NO_3-N plumes moving downward through the soil *** HN treatment resulted in significantly higher groundwater NO_3-N,relative to the LN treatment,with groundwater NO_3-N consistently exceeding the maximum safe level of 10 mg L^(-1),but groundwater NO_3-N above the maximum safe level was also observed in the LN treatment after heavy *** rain in June,July,and August 2003 caused increased NO_3-N leaching through the soil and elevated NO_3-N concentrations in the *** rise of the groundwater table into NO_3-N- rich soil layers also contributed to the increased NO_3-N concentrations in the *** results indicate that under conditions of average rainfall,soil NO_3-N was accumulated in the soil *** subsequent significantly higher- than-average rainfalls continuously flushed the soil NO_3-N into deeper layers and raised the groundwater table,which caused continuous groundwater contami

关键词：中国北方平原小麦玉米地下水污染

山西交城断裂北端及中段3个大型探槽全新世断错现象分析

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地震地质 2012年第1期34卷 76-92页

作者：郭慧江娃利谢新生中国地震局地壳应力研究所北京100085

前人在山西交城断裂带上开挖过多个探槽,揭露出全新世3次古地震事件,但其研究结果尚不能确定该断裂带全新世活动段的北部边界。近期在该断裂带北端和中段又开挖了3个大型探槽,其中在阳曲县泥屯盆地西界开挖的龙王沟探槽,是一个由多个探... 详细信息

前人在山西交城断裂带上开挖过多个探槽,揭露出全新世3次古地震事件,但其研究结果尚不能确定该断裂带全新世活动段的北部边界。近期在该断裂带北端和中段又开挖了3个大型探槽,其中在阳曲县泥屯盆地西界开挖的龙王沟探槽,是一个由多个探槽组合成的大探槽,该探槽揭示的地层断错信息,将交城断裂带全新世活动的范围向北延伸了20km。另外2个大型探槽分别为交城断裂带中段瓦窑沟东侧台地前缘的瓦窑探槽与市儿口沟西侧T1阶地前缘的新民探槽。这3个大探槽均揭示出全新世中期(14C测年值为距今5～6ka)的垆土和淤泥层,以及多组平行分布的断面,所揭示的全新世3次古地震事件具有断错事件活动的同步性,可与前人探槽揭示的全新世断层活动事件相对比。3次断错活动时间分别距今3.06～3.53ka、5.32ka左右或6.14ka左右、8.36ka左右;3次事件的时间间隔分别为2.02～2.84ka和2.22～3.04ka。这些断错事件的同震垂直位移为1.5～4.7m,显示了7级以上地表破裂型的强震活动。最后讨论了探槽中14C测年样品的影响因素。

关键词：探槽古地震期次全新世交城断裂带

Nd_(28)Fe_(66)B_6/Fe_(50)Co_(50)双层纳米复合膜的结构和磁性

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物理学报 2005年第10期54卷 4889-4893页

作者：敖琪张瓦利张熠吴建生上海交通大学高温材料与高温测试教育部重点实验室上海200030

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜... 详细信息

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜具有垂直于膜面的磁各向异性.从起始磁化曲线和小回线的形状特征可知,矫顽力机制主要是由畴壁钉扎控制.2)对于固定厚度(10nm)层的硬磁相Nd-Fe-B和不同厚度(dFeCo=1—100nm)层软磁相FeCo双层纳米复合膜,剩磁随软磁相FeCo厚度的增加快速增加,而矫顽力则减少.当dFeCo=5nm时,最大磁能积达到160×103A/m.磁滞回线的单一硬磁相特征说明,硬磁相Nd-Fe-B层和软磁相FeCo层之间的相互作用使两相很好地耦合在一起.剩磁和磁能积的提高是由于两相磁性交换耦合所致.

关键词： Nd-Fe-B/FeCo双层纳米复合膜交换耦合磁性增强纳米复合膜磁性薄膜晶体结构 Nd-Fe-B 超导量子干涉仪俄歇电子能谱仪矫顽力机制

Narrative minireview of the spatial epidemiology of substance use disorder in the United States:Who is at risk and where?

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World Journal of Clinical Cases 2023年第11期11卷 2374-2385页

作者： Diego F Cuadros Adam J Branscum Claudia m moreno Neil J macKinnon Digital Futures University of CincinnatiCincinnatiOH 45206United States Department of Biostatistics Oregon State UniversityCorvallisOR 97331United States Department of Physiology and Biophysics University of WashingtonSeattleWA 98195United States Department of Population Health Sciences Augusta UniversityAugustaGA 30912United States

Drug overdose is the leading cause of death by injury in the United *** incidence of substance use disorder(SUD)in the United States has increased steadily over the past two decades,becoming a major public health problem for the *** drivers of the SUD epidemic in the United States have changed over time,characterized by an initial heroin outbreak between 1970 and 1999,followed by a painkiller outbreak,and finally by an ongoing synthetic opioid *** nature and sources of these abused substances reveal striking differences in the socioeconomic and behavioral factors that shape the drug ***,the geospatial distribution of the SUD epidemic is not *** United States has specific locations where vulnerable communities at high risk of SUD are concentrated,reaffirming the multifactorial socioeconomic nature of this epidemic.A better understanding of the SUD epidemic under a spatial epidemiology framework is necessary to determine the factors that have shaped its spread and how these patterns can be used to predict new outbreaks and create effective mitigation *** narrative minireview summarizes the current records of the spatial distribution of the SUD epidemic in the United States across different periods,revealing some spatiotemporal patterns that have preceded the occurrence of *** analyzing the epidemic of SUD-related deaths,we also describe the epidemic behavior in areas with high incidence of ***,we describe public health interventions that can be effective for demographic groups,and we discuss future challenges in the study and control of the SUD epidemic in the country.

关键词： Substance use disorder Spatial epidemiology Risk factors Spatial statistics Disease mapping

Coupling Discriminating Statistical Analysis and Artificial Intelligence for Geotechnical Characterization of the Kampemba’s municipality Soils (Lubumbashi, DR Congo)

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Geomaterials 2020年第3期10卷 35-55页

作者： Kavula Ngoy Elysée Kasongo wa mutombo Portance Libasse Sow Ngoy Biyukaleza Bilez Kavula mwenze Corneille Tshibwabwa Kasongo Obed Civil Engineering Section Higher Institute of Applied Techniques of Lubumbashi Lubumbashi Democratic Republic of Congo Department of Geology Faculty of Science University of Lubumbashi Lubumbashi Democratic Republic of Congo Civil Engineering Department Higher Polytechnic School Cheikh Anta Diop University of Dakar Dakar Senegal Department of mines Polytechnic Faculty University of Lubumbashi Lubumbashi Democratic Republic of Congo Anvil mining Congo Kapulo Copper Project Lubumbashi Democratic Republic of Congo

This study focuses on the determination of physical and mechanical characteristics based on in vitro tests, by using field samples for the Kampemba urban area in the city of Lubumbashi. At the end of this study, we identified the soils according to their parameters, and established the geotechnical classification by determining their bearing capacity by the group index method using from the identification tests carried out. By using the AASHTO classification method (American Association for State Highway Transportation Official), the results obtained after our studies revealed five classes of soil: A-2, A-4, A-5, A-6, A-7 in a general way, and particularly eight subgroups of soil: A-2-4, A-2-6, A-2-7, A-4, A-5, A-6, A-7-5 and A-7-6 for the concerned area. The latter has given statistical analysis and deep learning based on multi-layer perceptron, the global values of the physical parameters. It’s about: 31.77% ± 1.05% for the limit of liquidity;18.71% ± 0.76% for the plastic limit;13.06% ± 0.79% for the plasticity index;83.00% ± 3.33% for passing of 2 mm sieve;76.22% ± 3.2% for passing of 400 μm sieve;89.07% ± 2.99% for passing of 4.75 mm sieve;70.62% ± 2.39% passing of 80 μm sieve;1.66 ± 0.61 for the consistency index;−0.67 ± 0.62 for the liquidity index and 8 ± 1 for the group index.

关键词： Geotechnical Classification Discriminant Factorial Analysis Artificial Intelligence Deep Learning multi-Layer Perceptron

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浅谈江汉油区废弃井治理工艺

江汉石油职工大学学报 2015年第3期28卷 51-53,64页

作者：万明中国石化江汉油田分公司井下作业处湖北潜江433123

江汉油区废弃井治理应在严格执行《江汉油田石油天然气井井控实施细则》基础上,遵循地层流体不进入井筒、各层位之间不相互窜通、地下水不受污染的原则。废弃井治理可分为前期准备、重建井口、井筒准备、挤堵打塞和治理收尾5个阶段。常... 详细信息

江汉油区废弃井治理应在严格执行《江汉油田石油天然气井井控实施细则》基础上,遵循地层流体不进入井筒、各层位之间不相互窜通、地下水不受污染的原则。废弃井治理可分为前期准备、重建井口、井筒准备、挤堵打塞和治理收尾5个阶段。常规井、套漏井、套损井、落物井以及多种问题并存的复杂井的治理,应根据井况特点,结合油田废弃井的处置要求,采取不同的治理技术措施与封井工艺。在治理过程中要继续坚持方案准备充分、设计评审过关、严格遵照设计施工。

关键词：江汉油区废弃井治理工艺封井井下作业

Assessing the impact of conceptual mineral systems uncertainty on prospectivity predictions

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Geoscience Frontiers 2022年第6期13卷 182-207页

作者： mark D Lindsay Agnieszka m.Piechocka mark W Jessell Richard Scalzo Jeremie Giraud Guillaume Pirot Edward Cripps Commonwealth Scientific and Industrial Research Organisation Mineral Resources Australian Resources Research CentreWA 6151Australia mineral Exploration Cooperative Research Centre Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaPerthWA 6009Australia ARC Centre for Data Analytics for Resources and Environments(DARE) Perth and SydneyAustralia University of Sydney School of Mathematics and StatisticsSydneyAustralia Universitéde Lorraine GeoRessourcesCNRS54000 NancyFrance The University of Western Australia Department of Mathematics and StatisticsPerthAustralia

The past two decades have seen a rapid adoption of artificial intelligence methods applied to mineral exploration. more recently, the easier acquisition of some types of data has inspired a broad literature that has examined many machine learning and modelling techniques that combine exploration criteria,or ’features’, to generate predictions for mineral prospectivity. Central to the design of prospectivity models is a ’mineral system’, a conceptual model describing the key geological elements that control the timing and location of economic mineralisation. The mineral systems model defines what constitutes a training set, which features represent geological evidence of mineralisation, how features are engineered and what modelling methods are used. mineral systems are knowledge-driven conceptual models, thus all parameter choices are subject to human biases and opinion so alternative models are ***, the effect of alternative mineral systems models on prospectivity is rarely compared despite the potential to heavily influence final predictions. In this study, we focus on the effect of conceptual uncertainty on Fe ore prospectivity models in the Hamersley region, Western Australia. Four important considerations are tested.(1) Five different supergene and hypogene conceptual mineral systems models guide the inputs for five forest-based classification prospectivity models model.(2) To represent conceptual uncertainty, the predictions are then combined for prospectivity model comparison.(3)Representation of three-dimensional objects as two-dimensional features are tested to address commonly ignored thickness of geological units.(4) The training dataset is composed of known economic mineralisation sites(deposits) as ’positive’ examples, and exploration drilling data providing ’negative’sampling locations. Each of the spatial predictions are assessed using independent performance metrics common to AI-based classification methods and subjected to geological pl

关键词： Uncertainty modelling Prospectivity Economic geology Geological plausibility Forest-based classification

1000mW级汽轮发电机转子绕组轴向通风冷却系统

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上海交通大学学报 2002年第7期36卷 999-1003页

作者：胡晟谭茀娃金如麟上海交通大学电力学院上海200030

对 1 0 0 0 mW级大型汽轮发电机冷却系统进行了研究 ,给出了转子绕组本体部分各匝导体通风道的局部阻力系数和沿程阻力系数的计算方法 .以一台 93 0 mW汽轮发电机为例 ,建立了转子绕组本体部分节点单元热阻等效网络的准三维热模型 ,从... 详细信息

对 1 0 0 0 mW级大型汽轮发电机冷却系统进行了研究 ,给出了转子绕组本体部分各匝导体通风道的局部阻力系数和沿程阻力系数的计算方法 .以一台 93 0 mW汽轮发电机为例 ,建立了转子绕组本体部分节点单元热阻等效网络的准三维热模型 ,从而可以计算出转子各匝导体的风量、流速和每匝导体各单元的温度 ,以及转子绕组本体部分的平均温度和最高温度 .通过计算结果与试验结果的比较。

关键词： 1000 mW级汽轮发电机转子绕组轴向通风冷却系统阻力系数准三维热模型风量流速

Festosterone treatment and cardiovascular events in prescription database studies

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Asian Journal of Andrology 2018年第2期20卷 138-144页

作者： molly m Shores Department of Psychiatry and Behavioral Sciences University of Washington School of Medicine VA Puget Sound Health Care System 1660 South Columbian Way Seattle WA 98108 USA

Over the past decade, there has been a substantial increase in the number of men who are treated with testosterone. Despite this increase in the use of testosterone, the risks of adverse cardiovascular events are unclear as meta-analyses have reported conflicting findings and no clinical studies have been large enough or long enough to adequately assess for cardiovascular risks. The goal of this paper is to review large prescription database studies of testosterone treatment and adverse cardiovascular events and mortality with the aim of providing some guidance for clinicians and researchers in this controversial area.

关键词： cardiovascular diseases cohort studies myocardial infarction stroke testosterone/adverse effects thrombosis