检索结果-南通市图书馆

Migration of ammonium nitrogen in ion-absorbed rare earth soils during and post in situ mining: a column study and numerical simulation analysis

在线全文

学校读者我要写书评

暂无评论

环境科学与工程前沿(英文) 2023年第8期17卷 137-151页

作者： Gaosheng Xi Xiaojiang Gao Ming Zhou Xiangmei Zhai Ming Chen xingxiang wang Xiaoying Yang Zezhen Pan Zimeng wang Department of Environmental Science and Engineering Fudan UniversityShanghai 200438China School of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuary Shanghai 202151China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200001China

Ion-absorbed rare earth mines,leached in situ,retain a large amount of ammonium nitrogen(NH4–N)that continuously releases into the surrounding environments.However,quantitative descriptions and predictions of the transport of NH4–N across mining area with hill slopes are not fully established.Here,laboratory column experiments were designed with an inclined slope(a sand box)to examine the spatial temporal transport of NH4–N in soils collected from the ionic rare earth elements(REE)mining area.An HYDRUS-2D model simulation of the experimental data over time showed that soils had a strong adsorption capacity toward NH4–N.Chemical non-equilibrium model(CNEM)could well simulate the transport of NH4–N through the soil-packed columns.The simulation of the transport-adsorption processes at three flow rates of leaching agents revealed that low flow rate enabled a longer residence time and an increased NH4-N adsorption,but reduced the extraction efficiency for REE.During the subsequent rainwater washing process,the presence of slope resulted in the leaching of NH4–N on the surface of the slope,while the leaching of NH4–N deep inside the column was inhibited.Furthermore,the high-intensity rainfall significantly increased the leaching,highlighting the importance of considering the impact of extreme weather conditions during the leaching process.Overall,our study advances the understanding of the transport of NH4–N in mining area with hills,the impact of flow rates of leaching agents and precipitation intensities,and presents as a feasible modeling method to evaluate the environmental risks of NH4–N pollution during and post REE in situ mining activities.

关键词： Ion-absorbed rare earth Ammonium nitrogen transport HYDRUS-2D Numerical simulation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于生态安全的我国土壤镉环境基准研究

地学前缘 2024年第2期31卷 130-136页

作者：丁昌峰周志高王玉荣张桃林王兴祥中国科学院南京土壤研究所江苏南京210008 中国科学院大学北京100049 中国科学院红壤生态实验站江西鹰潭335211

土壤镉(Cd)污染的生态安全问题不容忽视,我国目前尚缺乏基于生态风险的土壤Cd环境基准。本研究通过调研国内外关于土壤Cd的生态毒性研究,收集并筛选基于我国土壤的Cd毒性效应数据,采用物种敏感性分布法并结合Cd的生态毒性预测模型,推导... 详细信息

土壤镉(Cd)污染的生态安全问题不容忽视,我国目前尚缺乏基于生态风险的土壤Cd环境基准。本研究通过调研国内外关于土壤Cd的生态毒性研究,收集并筛选基于我国土壤的Cd毒性效应数据,采用物种敏感性分布法并结合Cd的生态毒性预测模型,推导不同用地方式下的土壤全量和EDTA提取态Cd生态安全环境基准。共收集与筛选出包含13个物种或生态过程的126个土壤Cd生态毒性数据,其中陆生植物毒性数据60个(6个物种)、无脊椎动物毒性数据39个(3个物种)、生态过程毒性数据27个(4种指标)。土壤Cd生态毒性预测模型研究结果表明,土壤pH是影响Cd生态毒性的最重要因子。自然保护地和农业用地、公园用地、住宅用地、商服及工业用地不同土壤pH值范围的土壤全量Cd生态安全基准分别为1.91~5.25、3.94~11.1、7.59~22.0和10.5~30.8 mg·kg^(-1),基于EDTA提取态Cd的生态安全基准分别为1.13~3.12、2.34~6.62、4.51~13.1和6.24~18.4 mg·kg^(-1)。研究结果可为我国土壤污染风险管控标准的制修订提供依据。

关键词：土壤镉生态毒性物种敏感性分布环境基准

Rice(Oryza sativa L.)seedlings enriched with zinc or manganese:Their impacts on cadmium accumulation and expression of related genes

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2021年第6期31卷 849-858页

作者： Gaoxiang HUANG Changfeng DING Yibing MA Yurong wang Zhigao ZHOU Shun'an ZHENG xingxiang wang Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) School of Geography and Environment Key Laboratory of Poyang Lake Wetland and Watershed ResearchMinistry of EducationJiangxi Normal UniversityNanchang 330022(China) Macao Environmental Research Institute Macao University of Science and TechnologyTaipa 999078Macao(China) Rural Energy and Environment Agency Ministry of Agriculture and Rural AffairsBeijing 100125(China) Ecological Experimental Station of Red Soil Chinese Academy of SciencesYingtan 335211(China) University of Chinese Academy of Sciences Beijing 100049(China)

Cadmium(Cd)contamination in paddy soils means that the rice produced there may be unsafe for human consumption.A hydroponic study was conducted to enrich rice seedlings with zinc(Zn)or manganese(Mn),and the uptake and transport characteristics of Cd in these Zn-and Mn-rich seedlings were subsequently investigated using a greenhouse pot trial.The results showed that hydroponic cultivation in 10-50μmol L^(-1) Zn(ZnSO_(4)·7 H_(2)O)or50-250μmol L^(-1) Mn(MnSO_(4)·H_(2)O)for 30 d had no significant impact on rice growth,while the accumulation of Zn and Mn was 7.31-18.5 and 25.4-47.7 times higher,respectively,than in the control(no Zn or Mn addition).The accumulation of Cd in the Zn-and Mn-rich rice plants was 26.3%-38.6% and 34.4%-44.5% lower than that in the control,respectively,and the translocation factors of Cd from roots to shoots also decreased by 23.3%-41.3% and 25.3%-37.0%,respectively,after transplanting to Cd-contaminated soils.Furthermore,the relative expression levels of OsIRT1(Oryza sativa iron-regulated transporter 1)were downregulated by 40.1%-59.3% and 16.0%-25.9%,respectively,in the Zn-and Mn-rich seedling roots.This downregulation may indicate a possible mechanism contributing to the reductions in Cd absorption.Field experiments confirmed that the Zn-and Mn-rich seedlings produced brown rice(unpolished rice grains)with significantly decreased concentrations of Cd(34.2%-44.4%).This study provides an innovative method for reducing the food safety risks from rice grown on slightly to moderately Cd-contaminated paddy soils.

关键词： absorption enrichment Cd contamination contaminated paddy soil gene expression hydroponics translocation factor

在线全文

学校读者我要写书评

暂无评论

基于机器学习方法的花生镉富集系数预测

农业环境科学学报 2024年第6期43卷 1230-1238页

作者：毕卫冬丁昌峰周志高王兴祥土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 南京210008 中国科学院大学北京100049 中国科学院红壤生态实验站江西鹰潭335211

通过采集我国14个省份花生主产区的100组土壤-花生样品,分析土壤-花生系统镉(Cd)污染特征及土壤理化性质,基于机器学习方法建立花生Cd富集系数预测模型并识别花生富集Cd的重要影响因素。结果表明,采集的全国范围土壤样品总体以酸性为主,... 详细信息

通过采集我国14个省份花生主产区的100组土壤-花生样品,分析土壤-花生系统镉(Cd)污染特征及土壤理化性质,基于机器学习方法建立花生Cd富集系数预测模型并识别花生富集Cd的重要影响因素。结果表明,采集的全国范围土壤样品总体以酸性为主,有60%的土壤pH<6.50,花生籽粒Cd含量均值为0.27 mg·kg^(-1),富集系数均值达到2.42。利用全国以及南北方产区分组数据构建的随机森林模型(R^(2)=0.930~0.966)对花生Cd富集系数的预测性能均明显优于相应的多元线性回归模型(R^(2)=0.471~0.657)。随机森林模型分析结果表明不同区域相对重要性较高的特征变量有所差异,影响北方产区花生Cd富集系数预测最重要的特征变量为土壤游离锰氧化物、游离铁氧化物含量和pH,而影响南方产区花生Cd富集系数预测最重要的特征变量为土壤游离锰氧化物、黏粒、游离铁氧化物和有机质含量。研究表明,相较于传统多元线性回归模型,随机森林模型对花生Cd富集系数的预测性能更为优越,为田间大尺度下土壤-花生系统中Cd的迁移预测提供了新的视角和解决方案。

关键词：土壤花生镉随机森林预测模型

Enrichment of Phosphate on Ferrous Iron Phases during Bio-Reduction of Ferrihydrite

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Geosciences 2012年第2期3卷 314-320页

作者： Qingman Li xingxiang wang Dan Kan Rebecca Bartlett Gilles Pinay Yu Ding Wei Ma Clinical Department School of Medicine Northwest University for Nationalities Lanzhou China Institute of Hydrobiology Chinese Academy of Sciences Wuhan China Institute of Soil Science Chinese Academy of Sciences Nanjing China School of Geography Earth and Environmental Sciences University of Birmingham Birmingham UK

The reduction of less stable ferric hydroxides and formation of ferrous phases is critical for the fate of phosphorus in anaerobic soils and sediments. The interaction between ferrous iron and phosphate was investigated experimentally during the reduction of synthetic ferrihydrite with natural organic materials as carbon source. Ferrihydrite was readily reduced by dissimilatory iron reducing bacteria (DIRB) with between 52% and 73% Fe(III) converted to Fe(II) after 31 days, higher than without DIRB. Formation of ferrous phases was linearly coupled to almost complete removal of both aqueous and exchangeable phosphate. Simple model calculations based on the incubation data suggested ferrous phases bound phosphate with a molar ratio of Fe(II):P between 1.14 - 2.25 or a capacity of 246 - 485 mg·P·g-1 Fe(II). XRD analysis indicated that the ratio of Fe(II): P was responsible for the precipitation of vivianite (Fe3(PO4)2·8H2O), a dominant Fe(II) phosphate mineral in incubation systems. When the ratio of Fe(II):P was more than 1.5, the precipitation of Fe(II) phosphate was soundly crystallized to vivianite. Thus, reduction of ferric iron provides a mechanism for the further removal of available phosphate via the production of ferrous phases, with anaerobic soils and sediments potentially exhibiting a higher capacity to bind phosphate than some aerobic systems.

关键词： Phosphate Iron Reduction Ferrihydrite Ferrous Iron Vivianite

Effects of several amendments on rice growth and uptake of copper and cadmium from a contaminated soil

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2008年第4期20卷 449-455页

作者： LI Ping wang xingxiang ZHANG Taolin ZHOU Dongmei HE Yuanqiu Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Heavy metals in variable charge soil are highly bioavailable and easy to transfer into plants. Since it is impossible to completely eliminate rice planting on contaminated soils, some remediation and mitigation techniques are necessary to reduce metal bioavailability and uptake by rice. This pot experiment investigated the effects of seven amendments on the growth of rice and uptake of heavy metals from a paddy soil that was contaminated by copper and cadmium. The best results were from the application of limestone that increased grain yield by 12.5-16.5 fold, and decreased Cu and Cd concentrations in grain by 23.0%--50.4%. Application of calcium magnesium phosphate, calcium silicate, pig manure, and peat also increased the grain yield by 0.3-15.3 fold, and effectively decreased the Cu and Cd concentrations in grain. Cd concentration in grain was slightly reduced in the treatments of Chinese milk vetch and zinc sulfate. Concentrations of Cu and Cd in grain and straw were dependent on the available Cu and Cd in the soils, and soil available Cu and Cd were significantly affected by the soil pH.

关键词： heavy metals amendment bioavailability uptake rice

Hemin-functionalized polypyrrole/paper-derived biochar electrocatalysts:Enhanced sensor platforms for H2O2

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2024年第2期34卷 280-289页

作者： Yuhang Jiang Tianshuang Bao Xiangchuan Zhao Qi wang Yue Cao Jun Cao xingxiang Ji Weimeng Si School of Materials Science and Engineering Shandong University of Technology State Key Laboratory of Biobased Material and Green Papermaking Qilu University of Technology (Shandong Academy of Sciences)

As a H2O2electrochemical biomimetic enzyme sensor,the stability,repeatability and sensitivity of hemin-based composites are closely connected with the loading of hemin on high-performance matrix.Herein,polypyrrole/paper-derived carbon（PPy/PC） nanocomposite was used for the construction of a hemin-based non-enzymatic sensor to detect H2O2.Where the poplar wood is used to obtain crude cellulose through a straightforward papermaking process.This crude cellulose is then subjected to pyrolysis to yield the desired paper-based carbon material.The hemin-decorated PPy/PC was demonstrated possessing remarkable electrocatalytic activity for H2O2reduction,and the possible mechanism of the reactions was discussed.The electrochemical sensor,utilizing the HPPy/PC composite,achieved a low detection limit of 30 nM,along with enhanced selectivity and stability under optimized conditions.The favorable results observed can primarily be attributed to the superior electrochemical performance of PPy/PC,as well as its unique 3D interconnected structure.This structure effectively impedes the self-dimerization of hemin,thereby ensuring the generation of active catalytic species.

关键词： Biochar H2O2 sensing Hemin Paper-based carbon materials Paper-making process

Triggerable Mutually Amplified Signal Probe Based SERS Microfluidics Platform for the Efficient Enrichment and Quantitative Detection of miRNA

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Triggerable Mutually Amplified Signal Probe Based SERS Micro...

Suppression of tissue inhibitors of metalloproteinases may reverse severe pulmonary arterial hypertension

第十一届全国化学生物学学术会议

作者： xingxiang wang Zhen-xing wang Na Zhang Xun Liu Meng-lei wang Su-juan Ye Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOE Qingdao University of Science and Technology

Sensitive detection of microRNAs（miRNAs） that serve as a disease marker could advance the diagnosis and treatment of diseases.Many methods used for quantitative detection of miRNAs,such as PCR-based approaches or the hybridization chain reaction,have presented challenges due to the complicated and time consuming-procedures that are required.In this manuscript,a simple triggerable mutually amplified signal（TMAS） probe was designed and enriched within the center of a microfluidic chip and then used for one-step quantitative detection of microRNAs via surface enhanced Raman scattering（SERS） technology.First,many mutually amplified double strands are produced via an enzyme-free target strand displacement recycling reaction initiated by the target miRNA,that result in the generation of an enhanced SERS signal.Second,microfluidic chips that utilize alternating current（AC） electrokinetic flow technology produce efficient mixing and rapid concentration to improve the DNA hybridization rate and further enhance the SERS signal intensity.This method enables the sensitive and rapid detection of miR-21 in human breast cancer cells within 30 min with a detection limit of 2.33 fM.Compared with traditional methods,this novel method overcomes the shortcomings resulting from complex operations,and has the advantages of high sensitivity,short assay time,and reduced sample usage.

关键词： AC electrokinetics gold nanoparticles microRNAs microfluidic chip SERS

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Suppression of tissue inhibitors of metalloproteinases may r...