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Relationship between heavy metals and dissolved organic matter released from sediment by bioturbation/bioirrigation

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Journal of Environmental Sciences 2019年第1期31卷 216-223页

作者： Yi He Bin men Xiaofang Yang Yaxuan Li Hui Xu Dongsheng wang State Key Laboratory of Environmental Aquatic Chemistry Research Centre for Eco-Environmental Science Chinese Academy of Sciences

Organic matter(OM) is an important component of sediment. Bioturbation/bioirrigation can remobilize OM and heavy metals that were previously buried in the sediment. The remobilization of buried organic matter, thallium(Tl), cadmium(Cd), copper(Cu) and zinc(Zn) from sediment was studied in a laboratory experiment with three organisms: tubificid,chironomid larvae and loach. Results showed that bioturbation/bioirrigation promoted the release of dissolved organic matter(DOM) and dissolved Tl, Cd, Cu and Zn, but only dissolved Zn concentrations decreased with exposure time in overlying water. The presence of organisms altered the compositions of DOM released from sediment,considerably increasing the percentage of fulvic acid-like materials(FA) and humic acidlike materials(HA). In addition, bioturbation/bioirrigation accelerated the growth and reproduction of bacteria to enhance the proportion of soluble microbial byproduct-like materials(SMP). The DOM was divided into five regions in the three-dimensional excitation emission matrix(3 D-EEM), and each part had different correlation with the dissolved heavy metal concentrations. Dissolved Cu had the best correlation with each of the DOM compositions, indicating that Cu in the sediment was in the organic-bound ***, the organism type and heavy metal characteristics both played a role in influencing the remobilization of heavy metal.

关键词： Bioturb ation/bioirrigation Heavy metal Sediment DOM

Carbon fiber cannot always reduce the wear of PEEK for orthopedic implants under DPPC lubrication

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Friction 2023年第3期11卷 395-409页

作者： Shuai YAN Shichao men Hongbo ZOU Haoji wang Zhongjiang ZHANG Chunshen wang Tianyi SUI Bin LIN Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China

Excellent wear resistance is an important feature of orthopedic ***,although pure polyetheretherketone(PEEK)is outperformed by carbon fiber-reinforced PEEK(CF-PEEK)for stability and durability under laboratory conditions,it is not clear whether CF-PEEK should be preferred in all real-world *** indicate that,under dipalmitoylphosphatidylcholine(DPPC)lubrication,the wear rates of PEEK are 35%-80%lower than the wear rates of CF-PEEK for different implant materials,speeds,loadings,and DPPC *** dynamics calculations confirm that DPPC self-assembles on the PEEK surface to form an easily adsorbed continuous phospholipid lubricating *** contrast,the carbon fibers on the CF-PEEK surface hinder the formation of the protective DPPC film and the CF-PEEK surface is thus subject to faster wear.

关键词： polyetheretherketone(PEEK) carbon fiber-reinforced PEEK(CF-PEEK) dipalmitoylphosphatidylcholine(DPPC) orthopedic implants self-assembly

Design and biosynthesis of functional protein nanostructures

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Science China(Life Sciences) 2020年第8期63卷 1142-1158页

作者： Feng Li Dianbing wang Juan Zhou Dong men Xian-En Zhang State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China National Laboratory of Biomacromolecules CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China

Proteins are one of the major classes of biomolecules that execute biological functions for maintenance of *** kinds of nanostructures self-assembled from proteins have been created in nature over millions of years of evolution,including protein nanowires,layers and *** protein nanostructures can be reconstructed and equipped with desired new *** from and manipulating the self-assembly of protein nanostructures not only help to deepen our understanding of the nature of life but also offer new routes to fabricate novel nanomaterials for diverse *** review summarizes the recent research progress in this field,focusing on the characteristics,functionalization strategies,and applications of protein nanostructures.

关键词： protein nanostructures protein nanowires S-layer protein nanocages self-assembly biosynthesis functionalization

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二维气相色谱在乙烯装置分析中的研究与应用

化工设计通讯 2018年第3期44卷 240-240页

作者：王梦乔中沙(天津)石化有限公司天津300270

新时期我国石化产业规模的不断扩大,对性能可靠的乙烯装置依赖程度逐渐加深。实践中为了实现乙烯装置的平稳运行,保持其良好的裂解气效果,则需要注重多维气相色谱在该装置分析中的应用。基于此,就二维气相色谱在乙烯装置分析中的研究与... 详细信息

新时期我国石化产业规模的不断扩大,对性能可靠的乙烯装置依赖程度逐渐加深。实践中为了实现乙烯装置的平稳运行,保持其良好的裂解气效果,则需要注重多维气相色谱在该装置分析中的应用。基于此,就二维气相色谱在乙烯装置分析中的研究与应用展开论述,以便保持该装置良好的运行工况。

关键词：二维气相色谱乙烯装置应用裂解气

1999至2008年高血压专科住院患者病因构成的分析

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中华心血管病杂志 2010年第10期38卷 939-942页

作者：李南方林丽王磊王新玲祖菲亚张德莲常桂娟张艳敏周克明努尔古丽李涛胡君丽孔剑琼王梦卉骆秦新疆维吾尔自治区人民医院高血压科新疆维吾尔自治区高血压研究所乌鲁木齐830001

目的分析1999至2008年新疆维吾尔自治区人民医院高血压专科住院患者病因构成及演变趋势.方法采用回顾性研究方法 ,分析10年间7809例高血压专科住院患者的病因构成及在各年度分布情况,并对变化趋势进行分析.结果（1）7809例高血压专... 详细信息

目的分析1999至2008年新疆维吾尔自治区人民医院高血压专科住院患者病因构成及演变趋势.方法采用回顾性研究方法 ,分析10年间7809例高血压专科住院患者的病因构成及在各年度分布情况,并对变化趋势进行分析.结果（1）7809例高血压专科住院患者中原发性高血压5867例,占75.1%,继发性高血压1942例,占24.9%.（2）2008年和1999年继发性高血压所占的比例分别为39.3%（665/1692）、9.5%（32/338）.10年间继发性高血压所占的比例逐年升高（χ2=387.621,P＜0.001＝.病因构成中,睡眠呼吸暂停综合征（OSAS）2008年占20.3%（343/1692）,1999年占0.6%（2/338）（χ2=304.025,P＜0.001＝原发性醛固酮增多症（PA）2008年占5.3%（89/1692）,1999年占2.9%（10/338）（χ2=42.845,P＜0.001＝其他病因所占比例变化较小.（3）2004至2008年PA合并OSAS比例逐年升高（χ2=26.376,P＜0.001＝,PA中OSAS占23.9%（65/272）,OSAS中PA占6.7%（65/963）.结论 1999至2008年高血压住院患者中,继发性高血压所占的比例逐年升高.在继发性高血压中,OSAS、PA所占的比例最高,同时应注意OSAS与PA两种继发性因素可能并存.

关键词：高血压病因学

The electrocatalytic activity of BaTiO3 nanoparticles towards polysulfides enables high-performance lithium-sulfur batteries

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Journal of Energy Chemistry 2020年第9期29卷 208-216,I0007页

作者： Hongcheng Gao Shunlian Ning Jiasui Zou Shuang men Yuan Zhou Xiujun wang Xiongwu Kang New Energy Research Institute School of Environment and EnergySouth China University of TechnologyGuangzhou 510006GuangdongChina School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640GuangdongChina

The slow redox dynamics and dissolution of polysulfides in lithium-sulfur(Li-S)batteries result in poor rate performance and rapid decay of battery capacity,thus limiting their practical *** barium titanate(BT)nanoparticles have been reported to effectively improve the electrochemical performance of Li-S batteries due to the inherent self-polarization and high adsorption capacity of the BT nanoparticles towards *** in this paper,BT nanoparticles,behave as highly efficient electrocatalyst and demonstrate much higher redox dynamics towards the conversion reaction of polysulfides and Li2S than TiO2,as shown by both electrochemical measurements and density functional theory *** coupling of the sulfur host of the hollow and graphitic carbon flakes(HGCF)and the BT nanoparticles(HGCF/S-BT)enable excellent electrochemical performance of Li-S batteries,delivering a0.047%capacity decay per cycle in 1000 cycles at 1 C,788 mAh g^-1 at 2 C and a reversible capacity of613 mAh g^-1 after 300 cycles at a current density of 0.5 C at a S loading of 3.4 mg cm^-***/S-BT also shows great promise for practical application in flexible devices as demonstrated on the soft-packaged Li-S batteries.

关键词： Electrocatalysis Redox reaction Li-S battery Polysulfide DFT calculation

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甘蓝型油菜雄性不育基因转化体系的探索

西南农业学报 1999年第1期12卷 45-50页

作者：万萌王敬乔寸守铣邱仕芳李根泽曾黎琼和江明云南省农科院生物技术研究所

用携带ＴＡ２９—Ｂａｒｎａｓｅ雄性不育基因的农杆菌转化“双低”花培油菜，获得了大量转基因植株。用油菜的带柄子叶及下胚轴等外植体与携带载体质粒的农杆菌共培养后，将其转移到诱导愈伤组织及芽的培养基上培养，并同时进行卡那霉... 详细信息

用携带ＴＡ２９—Ｂａｒｎａｓｅ雄性不育基因的农杆菌转化“双低”花培油菜，获得了大量转基因植株。用油菜的带柄子叶及下胚轴等外植体与携带载体质粒的农杆菌共培养后，将其转移到诱导愈伤组织及芽的培养基上培养，并同时进行卡那霉素的抗性筛选，２～４周后，在子叶柄基部及愈伤组织上出现小丛芽，将其切下转入Ｂ５加卡那霉素的培养基中进一步筛选并生根，再将生根的正常绿色植株移栽于花盆中。在五叶期，用５０ｍｇ／ｍ１的卡那霉素注射于真叶的叶脉中，进一步筛选，可得到完全正常的绿苗，说明卡那霉素抗性标记基因（ＮＰＴⅡ）已转入油菜植株，进一步的植株鉴定及分子生物学检测另文详述。

关键词：甘蓝型油菜农杆菌雄性不育基因转化油菜

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洛阳基本烟田不同茬口土壤特征分析

江西农业学报 2010年第12期22卷 66-68页

作者：江凯李彰王闷灵李友军宋朝鹏王伟杰河南省烟草公司洛阳市公司河南洛阳471000 河南科技大学河南洛阳471000 河南农业大学河南郑州450002 洛阳市烟草公司嵩县分公司河南嵩县471400

通过对河南洛阳基本烟田不同茬口105个土壤样品分析,评价了洛阳基本烟田主要茬口植烟土壤的养分现状.结果表明:不同茬口(烟草、红薯、花生、大豆、谷子、芝麻、玉米、辣椒)土壤有机质含量平均为1.31%,其平均含量大小顺序为辣椒<花生<大... 详细信息

通过对河南洛阳基本烟田不同茬口105个土壤样品分析,评价了洛阳基本烟田主要茬口植烟土壤的养分现状.结果表明:不同茬口(烟草、红薯、花生、大豆、谷子、芝麻、玉米、辣椒)土壤有机质含量平均为1.31%,其平均含量大小顺序为辣椒<花生<大豆<谷子<烟草<芝麻<红薯<玉米;不同茬口土壤有效氮介于1.00%～1.50%之间,由低到高排列为辣椒<花生<谷子<烟草<大豆<芝麻<红薯<玉米,需注意氮肥使用量;不同茬口土壤全磷含量低于优质烟叶生产的适宜范围或在范围下限,需要增施磷肥并提高磷素有效性;不同前茬作物对土壤缓效钾、速效钾的影响都较小,均在生产优质烟叶的土壤速效钾含量范围内;不同茬口土壤水溶性氯含量之间差异较小,介于4.79～5.76 mg/kg之间,较为适宜生产优质烟叶;不同茬口土壤有效B、有效Cu处于缺乏至极度缺乏状态;不同茬口土壤有效Mn含量差异较大,处于丰富至极度缺乏状态;不同茬口土壤有效锌、有效铁含量处于中等供应水平.

关键词：洛阳不同茬口土壤有效锌特征分析 Different 优质烟叶土壤有机质含量芝麻玉米烟草土壤样品分析土壤速效钾生产辣椒花生红薯谷子大豆有效铁含量土壤有效氮

施氮量品种与密度互作对豫西烟叶产量和质量的影响

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干旱地区农业研究 2014年第5期32卷 127-131页

作者：毛家伟徐敏张翔叶红朝李国平王闷灵江凯孙洪魁孔德辉河南省农业科学院植物营养与资源环境研究所河南郑州450002 河南省烟草公司河南郑州450008 洛阳市烟草公司河南洛阳471000

为探讨豫西烟区最优的栽培措施组合,采用正交试验研究了不同品种、氮用量和密度对烟叶化学品质和经济性状的影响。结果表明:3个因素相比,品种对总糖和还原糖影响最大;施氮量增加使烟叶总氮含量增加;3个因素对中部叶化学成分协调性综合... 详细信息

为探讨豫西烟区最优的栽培措施组合,采用正交试验研究了不同品种、氮用量和密度对烟叶化学品质和经济性状的影响。结果表明:3个因素相比,品种对总糖和还原糖影响最大;施氮量增加使烟叶总氮含量增加;3个因素对中部叶化学成分协调性综合评价得分的影响大小顺序为施氮量>品种>密度,获得化学成分最协调的栽培组合为A1B2C2(品种:秦烟96;移栽密度:16 500株·hm-2;施氮量:67.5 kg·hm-2);从产量上分析,3个因素对产量的影响大小顺序为品种>施氮量>密度,要获得产量最高的组合为A3B3C3(品种:豫烟6号;移栽密度:18000株·hm-2;施氮量:90.0 kg·hm-2);从产值上分析,最好的组合为A1B2C2(品种:秦烟96;移栽密度:16 500株·hm-2;施氮量:67.5 kg·hm-2),其产值、均价和上等烟比例分别为62 770.5元·hm-2、19.21元·kg-1和58.6%。综合分析,在豫西烟区前期干旱后期降水分配较均匀且光照充足的条件下,可选择品种秦烟96,种植密度16500株·hm-2,氮肥施用量67.5 kg·hm-2的栽培技术进行推广应用。

关键词：氮用量品种密度产量产值化学品质