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Journal of Environmental Sciences 2022年第2期34卷 269-279页

作者： Yanhong Wang Xinyan Shi Xianxin Huang Chunlei Huang Helin Wang hanqin yin Yixian Shao Ping Li State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Zhejiang Institute of Geological Survey Hangzhou 311203China

Selenium(Se)is an essential micronutrient for lives.Indigenous microbial communities play an important role on Se geochemistry in soils.In this study,the microbial community composition and functions of 53 soil samples were investigated using high-throughput sequencing.Samples were divided into 3 groups with different farming types based on the measured geochemical parameters and microbial functional structures.Results indicated that putative Se related bacteria Bacillus,Dyella,Paenibacillus,Burkholderia and Brevibacillus were dominant in dryland plantation soils which were characterized with higher available Se and low contents of H_(2)O,total organic carbon(TOC),NH_(4)^(+) and NO_(2)^(-).In contrast,the putative denitrifier Pseudomonas dominated in flooded paddy soils with higher TOC,NO_(3)^(-) and organic Se,whereas genera Rhizobium,Nitrosospira,and Geobacter preferred woodland soils with higher oxidation-reduction potential(ORP),pH,NH_(4)^(+) and Fe.Farming patterns resulted in distinct geochemical parameters including moisture,pH,ORP,TOC,and contents of soluble Fe,NO_(2)^(-) and NH_(4)^(+),shaping the microbial communities,which in turn affected Se forms in soils.This study provides a valuable insight into understanding of Se biogeochemistry in soils and prospective strategy for Se-rich agriculture production.

关键词： Selenium biogeochemistry Indigenous microbial community Farming patterns High-throughput sequencing FAPROTAX

Impact of Phosphate Solubilizing Bacterial Agent on Cadmium Bioavailability and Microbial Communities in Soil and Cd Accumulation in Lettuce Plants

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Journal of Earth Science 2023年

作者： Yue Yu Ping Li Yanhong Wang Xinzhe Lu Chunlei Huang Songle Zhang hanqin yin Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science China University of Geosciences Zhejiang Institute of Geosciences State Key Laboratory of Biogeology and Environmental Geology

Cadmium(Cd) contamination in soil can lead to food chain accumulation and greatly impacts on human health. Bioremediation has gained more and more attention due to its environmentfriendly, high efficiency and low-cost. In this work, we studied the impact of phosphate solubilizing bacterial agent(PSBA) on Cd bioavailability, microbial communities in soil and Cd accumulation in lettuce plants with pot experiment and field trial. Results of pot experiment showed that PSBA could decrease the bioavailability of Cd(Cd-acid extractable from 3.30 to 2.34 mg/kg, Cd-reducible from 1.94to 1.56 mg/kg), promote lettuce plants growth(increased with 33.85% height and with 33.65% fresh weight) and reduce the accumulation of Cd(from 5.85 to 3.73 mg/kg) in lettuce plants. High-throughput sequencing identified that PSBA could change the composition and structure of the soil microbial communities. The relative abundances of the three ecologically beneficial bacterial families of Pseudomonadaceae, Burkholderiaceae, and Enterobacteriaceae increased from 2.29% to 5.13%, 0.56% to 5.24%, and 1.87% to 16.93%, respectively. And the former two were positively correlated with redox potential(Eh)(R2: 0.474, p<0.05, R2: 0.590, p<0.01, respectively). The bacterial networks were more complex in PSBA treatment, reflecting through more links(from 1 893 to 2 185) and a higher average degree(from 38.242 to 45.052) and density(from 0.390 to 0.469). Results of field trial demonstrated that PSBA could also decrease Cd content in lettuce plants and microbial composition in soil. This study indicated that PSBA could be served as an alternative material in bioremediation of Cd contamination in soil.

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A novel selenite-reducing bacterium Bacillus pseudomycoides SA14 isolated from Se-enriched soil and its potential Se biofortification on Brassica chinensis L.

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Journal of Earth Science 2022年

作者： Xianxin Huang Yanhong Wang Helin Wang Xinyan Shi Chunlei Huang hanqin yin Yixian Shao Ping Li State Key Laboratory of Biogeology and Environmental Geology， China University of Geosciences Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science， China University of Geosciences Zhejiang Institute of Geological Survey

Microbial participation in biofortification can improve the availability of selenium (Se) in soil and contribute to the enrichment of Se in crops. In this study， a selenite (Se(Ⅳ)) reducing strain was isolated from Se-rich soil， and its Se transformation and bioenhancement ability were studied. The strain was identified as Bacillus pseudomycoides and could reduce more than 93.48% of 1.0 mmol/L Se(Ⅳ) in 54 h. The results of scanning electron microscope (SEM) and energy dispersive X-ray spectrometry (EDS) showed that Se(Ⅳ) was reduced to Se(0)， and Se nanoparticles (SeNPs) were eventually formed. In pot experiments， B. pseudomycoides SA14 could promote the bioavailable Se in soils and the concentration of Se in Brassica chinensis L.. The concentrations of water-soluble Se， ion exchange Se and carbonate-binding Se in soil were increased by 23.13%， 22.05% and 30.89%， respectively. The Se concentration of Brassica chinensis L. in pot experiments was increased by 145.05%. The relative abundance of Bacillus in soil increased from 0.97% to 2.08% in the pot experiments. As far as we know， this is the first report of Se reduction by B. pseudomycoides. This study might provide a prospective strategy for microbial fortification of Se in crops.

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Spatio-temporal variation prediction on Cd content in the rice grains from Northern Zhejiang Plain during 2014–2019 based on high-precision soil geochemical data

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Journal of Geographical Sciences 2023年第2期33卷 413-426页

作者： yin hanqin LU Xinzhe SUN Rui HUANG Chunlei KANG Zhanjun XU Mingxing WEI yingchun CAI ZiHua State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Technology Innovation Center of Ecological Evaluation and Remediation of Agricultural Land in Plain Area MNRHangzhou 311200China Zhejiang Institute of Geological Survey Hangzhou 311200China

In recent years,Cadmium(Cd)pollution has been found in many soil geochemical surveys in Northern Zhejiang Plain,a crucial rice production area in East China,located in the lower Yangtze River.To more scientifically predict the effect of soil Cd on rice safety,data including 348 local rhizosphere soil-rice samples obtained in 2014 were used in this study.Meanwhile,we extracted 90% of random samples as variables based on soil Cd content(Cd_(soil)),soil organic matter(SOM),pH,and other indicators.In addition,a multivariate linear model for rice Cd content(Cd_(rice))prediction based on the indicators including the soil Cd content(Cd_(soil)),the soil organic matter(SOM),and the pH value.The remaining 10%of random samples were used for the significance test.Based on the 2014 soil Cd content(Cd_(soil14))and the 2019 soil Cd content(Cd_(soil19)),this study predicted Cd content in 2019 rice grains(Cd_(p-rice19)).The spatio-temporal variation of Cdrice was contrasted in the five years from 2014 to 2019,and the risk areas of rice safety production were analyzed using the Geographical Information System(GIS).The results indicated that compared with the actual Cd content in 2014 rice grains(Cdrice14),the proportion of Cd_(p-rice19),which exceeded the standard food level in China(GB2762-2017),increased dramatically.Moreover,the high-value areas of Cdrice distributed greatly coincidentally in these two years.By contrast,both Cdrice and Cdsoil show very different spatial scales.The dominant reason is the distribution of the local canal systems,indicating that economic activities and agricultural irrigation may aggravate the risk of soil Cd pollution,thus threatening safe rice production.

关键词： Northern Zhejiang Plain soil cadmium pollution rice safety multivariate linear model

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页岩气水平井振动固井套管柱振动特性研究

振动与冲击 2024年第9期43卷 149-157,194页

作者：齐林山尹宜勇曲从锋刘斌辉王立琰白翰钦王通中国农业大学工学院北京100083 中国石油集团工程技术研究院有限公司北京102206 北京康布尔石油技术发展有限公司北京102206

为了求解页岩气水平井振动固井套管柱振动特性和动力响应,考虑扶正器分布支承的特点,运用传递矩阵法建立了页岩气水平井套管柱的动力学模型,并通过试验验证了套管柱动力学模型的准确性。在此基础上,研究了扶正器支承和套管柱参数对套管... 详细信息

为了求解页岩气水平井振动固井套管柱振动特性和动力响应,考虑扶正器分布支承的特点,运用传递矩阵法建立了页岩气水平井套管柱的动力学模型,并通过试验验证了套管柱动力学模型的准确性。在此基础上,研究了扶正器支承和套管柱参数对套管柱振动特性的影响,探索了振动固井工况下套管柱的动力响应和振幅衰减规律。研究结果表明:扶正器刚度增大、扶正器支承数量增加和套管外径增大均会导致套管柱固有频率的增加;扶正器刚度增大会加快套管柱振幅衰减;增大激振力的同时利用低频共振能提高套管柱振动有效传播距离。该研究能够为页岩气水平井振动固井装备设计提供有益参考。

关键词：页岩气水平井套管柱传递矩阵振动特性动力响应

铜陵市大气降尘中Cd元素污染特征及其对土壤的影响

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地质论评 2011年第2期57卷 218-222页

作者：殷汉琴周涛发陈永宁陈富荣袁峰李湘凌浙江省地质调查院杭州311203 安徽省地质调查院合肥230001 合肥工业大学资源与环境工程学院合肥230009

为了评价有色金属矿山城市大气降尘中重金属元素的污染状况、来源及其对土壤重金属累积的影响,分析测试了铜陵市大气降尘样品中Cd元素的含量。分析结果表明,降尘样品中Cd元素的平均含量为16.44μg/g,明显高于安徽省江淮流域多目标调查... 详细信息

为了评价有色金属矿山城市大气降尘中重金属元素的污染状况、来源及其对土壤重金属累积的影响,分析测试了铜陵市大气降尘样品中Cd元素的含量。分析结果表明,降尘样品中Cd元素的平均含量为16.44μg/g,明显高于安徽省江淮流域多目标调查中铜陵土壤Cd元素的平均含量;降尘中Cd元素含量较高的样品出现在矿山和冶炼厂附近。用富集因子法定性地判断了各采样点Cd元素的来源,大气降尘中Cd元素的富集因子均值为78.8,表明铜陵市大气降尘中Cd元素污染严重,且矿石的开采和冶炼对大气降尘中Cd污染的贡献较大,是研究区大气污染中重金属的主要来源。大气降尘对土壤Cd的输入通量较大,达到1.84mg/(m2·a),远高出合肥、马鞍山等城市。

关键词：大气降尘 Cd元素重金属污染矿山城市沉降通量铜陵

龙游硫铁矿区农田土壤重金属污染的空间变异及在水稻中的积累

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土壤 2017年第4期49卷 760-769页

作者：张奥博褚先尧殷汉琴徐明星黄春雷宋明义浙江省地质调查院杭州311203

为了解浙江龙游硫铁矿区农田重金属污染状况,采集矿区265件农田土壤样品,分析8种重金属Cu、As、Hg、Zn、Cd、Ni、Pb、Cr元素全量,利用地统计学软件GS+9.0对研究区土壤各元素指标进行半变异函数拟合,并利用普通克里格法进行插值并绘制空... 详细信息

为了解浙江龙游硫铁矿区农田重金属污染状况,采集矿区265件农田土壤样品,分析8种重金属Cu、As、Hg、Zn、Cd、Ni、Pb、Cr元素全量,利用地统计学软件GS+9.0对研究区土壤各元素指标进行半变异函数拟合,并利用普通克里格法进行插值并绘制空间分布图。采集30件水稻籽粒样品,分析重金属在研究区中水稻籽粒的累积特征,并进行了健康风险评价。结果表明:矿区土壤中8种重金属元素的变异系数从0.72到1.76,离散程度较高。8种重金属的土壤空间半变异函数Cu、As、Hg元素符合指数模型,Zn、Cd、Ni、Pb符合球状模型,Cr符合高斯模型。元素Cu、Pb、Zn、Cr、Ni的块金值与基台值的比值C0/C0+C都小于0.25,说明空间变化主要受地质背景等因素影响;元素Cd、Hg和As的块金值与基台值的比值C0/C0+C在0.25~0.75之间,说明除了地质背景因素,人为活动等随机因素也有影响。矿区水稻籽粒中重金属Ni和Cd的变异系数最高,分别为0.95和0.87,说明Ni和Cd元素可能存在异常积累。矿区水稻籽粒对重金属的富集能力由大到小依次为Cd、Zn、Cu、Ni、As、Hg、Cr、Pb。健康风险评价结果表明矿区农田水稻籽粒中元素As、Cd的风险商大于1,存在潜在健康风险;而其他6种重金属Cu、Hg、Zn、Ni、Pb和Cr基本属于安全范围。

关键词：龙游黄铁矿重金属污染空间分布变异函数健康风险

基于层次聚类法和主成分分析法的铜陵市大气降尘污染元素来源解析研究

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地质论评 2010年第2期56卷 283-288页

作者：李湘凌周涛发殷汉琴张鑫袁峰范裕陈永宁陈兴仁陈富荣贾十军合肥工业大学资源与环境工程学院合肥230009 安徽省地质调查院合肥230001 中国科学院地质与地球物理研究所北京100029

本文采用层次聚类法和主成分分析法对有色金属矿山城市-铜陵市的大气降尘中污染元素,主要是重金属元素的来源进行了识别,并分析了各来源所占的比例。结果显示,铜陵市大气降尘中污染物主要来源于冶金和采矿,其次为燃煤、交通和土壤扬尘等... 详细信息

本文采用层次聚类法和主成分分析法对有色金属矿山城市-铜陵市的大气降尘中污染元素,主要是重金属元素的来源进行了识别,并分析了各来源所占的比例。结果显示,铜陵市大气降尘中污染物主要来源于冶金和采矿,其次为燃煤、交通和土壤扬尘等,其贡献率分别为冶金源+采矿源43.29%,燃煤源32.23%,交通源和土壤源10.53%,其他源13.94%。因此,优先控制冶金尘、采矿尘和燃煤尘,可以有效降低铜陵市大气降尘中污染元素的含量。

关键词：大气降尘层次聚类法主成分分析法来源解析铜陵市

Microstructure and Mechanical Properties of Cu Matrix Composites Reinforced by TiB_(2)/TiN Ceramic Reinforcements

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1609-1617页

作者： Jinwei yin Peilong Zhou hanqin Liang Dongxu Yao Yongfeng Xia Kaihui Zuo YuPing Zeng State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Cu matrix composites reinforced by TiB_(2)/TiN ceramic reinforcements(Cu/TBN composites)were prepared by hot pressing method.Prior to the hot pressing,Cu/TiB_(2)/TiN composite powders(CTBN powders),which were used as the starting materials of Cu/TBN composites,were fabricated by self-propagating high-temperature synthesis method.The CTBN particles were found to be in a special core–shell structure with a Cu–Ti alloy core and a TiB_(2)/TiN ceramic shell.The test results presented obvious improvements in mechanical properties.The highest ultimate tensile strength reached up to 297 MPa,77 MPa higher than that of Cu.And the highest hardness reached up to 70.7 HRF,15.7 HRF higher than that of Cu.A comparative study indicated that the core–shell structured particles could bring about more obvious strengthening eff ect than the traditional irregularly shaped particles,which was due to the improved Cu/ceramics interfacial bonding,the linkage strengthening effect of both TiB_(2) and TiN,and higher load bearing ability of the core–shell structured reinforcements.

关键词： Cu matrix composite Microstructure Mechanical property Self-propagating high-temperature synthesis(SHS)

The improved mechanical properties of Al matrix composites reinforced with oriented β-Si3N4 whisker

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Journal of Materials Science & Technology 2019年第7期35卷 1345-1353页

作者： Chenxu Zhang Yu-Ping Zeng Dongxu Yao Jinwei yin Kaihui Zuo Yongfeng Xia hanqin Liang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China

The β-Si3N4 whiskers (β-Si3N4w) reinforced A1 matrix com posites were first fabricated by hot pressing, then treated through hot extrusion. The microstructure characterization dem onstrated the preferred orientations of both β-Si3N4w and A1 grains in the as-extruded composites. It indicated th at β-Si3N4w were aligned along the extrusion direction and A1 grains exhibited a distinct ai texture. The interface betw een β-Si3N4w and A1 was in a good bonding status without voids and reaction products. Effects of extrusion process on the mechanical properties of com posites were also investigated. The results indicated the extrusion process had a prom inent strengthening effect on the mechanical properties of composites. The maxim umyield strength and ultim ate tensile strength of com posites reached up to 170 and 289 MPa, respectively, accompanied by a 12.3% elongation at fracture w hen the w hisker fraction was 15 vol.%. This im provem ent was collectively attributed to the densification of composites, the strong interface, and the preferred orientation inside composites. The yield strength of the composites reinforced with 5 vol.%β-Si3N4w corresponded well w ith the theoretical value from different strengthening mechanisms.

关键词： Metal-matrix composites (MMC) β-Si3N4 whiskers Preferred orientation Interface Mechanical properties Extrusion