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TRACE METALS IN VANDA LAKE IN ANTARCTICA——A VERTICAL MIGRATION MODEL OF TRACE METALS IN CLOSED BASIN

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Science China Chemistry 1992年第11期35卷 1397-1408页

作者：于昇松 W.j.green P.A.NIXON Institute of Salt Lakes Academia Sinica Xining 810008 PRC School of Interdisciplinary Studies Miami University Ohio U. S. A.

Vanda Lake, a typical dimictic CaCl_2 type salt lake, is located in the Wright Valley inAntarctica. Based on the chemical and physical features of the salt lake water, the authorsdiscussed the vertical geochemical distribution of Fe, Mn, Pb, Cr, Cu, Co, Ni, Cd in the lake,and their vertical migration in lake waters, and have tried to set up a model of vertical mi-gration of these trace elements in the water of a closed chloride type salt lake.

关键词： Antarctica trace elements ion activity product

Revolutionizing plasmonic platform via magnetic field-assisted confined ultrafast laser deposition of high-density,uniform,and ultrafine nanoparticle arrays

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International journal of Extreme Manufacturing 2024年第3期6卷 428-438页

作者： jin Xu Lingfeng Wang Peilin Yang Haoqing jiang Huai Zheng Licong An Xingtao Liu Gary j Cheng School of Industrial Engineering Purdue UniversityWest LafayetteIN 47906United States of America Institute of Technological Sciences Wuhan UniversityWuhanHubei 430072People’s Republic of China

The remarkable capabilities of 2D plasmonic surfaces in controlling optical waves havegarnered significant ***,the challenge of large-scale manufacturing of uniform,well-aligned,and tunable plasmonic surfaces has hindered their *** address this,we present a groundbreaking tunable plasmonic platform design achieved throughmagnetic field(MF)assisted ultrafast laser direct deposition in *** precise control of metal nanoparticles(NPs),with cobalt(Co)serving as the model material,employing an MF,and fine-tuning ultrafast laser parameters,we have effectively converted coarse and non-uniform NPs into densely packed,uniform,and ultrafine NPs(~3 nm).This revolutionary advancement results in the creation of customizable plasmonic‘hot spots,’which play a pivotal role insurface-enhanced Raman spectroscopy(SERS)*** profound impact of this designable plasmonic platform lies in its close association with plasmonic resonance and *** the plasmonic nanostructures resonate with incident light,they generate intense local electromagnetic fields,thus vastly increasing the Raman scattering *** enhancement leads to an outstanding 2–18 fold boost in SERS performance and unparalleled sensing sensitivity down to 10^(-10)***,the plasmonic platform also demonstratesrobustness,retaining its sensing capability even after undergoing 50 cycles of rinsing andre-loading of ***,this work adheres to green manufacturing standards,making it an efficient and environmentally friendly method for customizing plasmonic‘hot spots’inSERS *** study not only achieves the formation of high-density,uniform,and ultrafine NP arrays on a tunable plasmonic platform but also showcases the profound relation betweenplasmonic resonance and energy *** outstanding results observed in SERS sensors further emphasize the immense potential of this technology for energy-relatedapplications,including photocatalysis,ph

关键词： magnetic field manipulation laser deposition metasurface SERS

Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： j.Touche C.Calvaruso P.De Donato M.-P.Turpault INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Utilization of municipal solid waste incineration fly ash in lightweight aggregates

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journal of Central South University 2012年第3期19卷 835-841页

作者：谭文发王里奥黄川刘元元 j.E.green D.Newport T.green State Key Laboratory for Coal Mine Disaster Dynamics and Control Resource and Environmental Science CollegeChongqing University Faculty of Urban Construction and Environmental Engineering Chongqing University Sustainability Research Institute University of East London RTAL(H.K.)Limited

Washing pre-treatrnent of municipal solid waste incineration （MSWI） fly ash blended with shale and sludge was utilized in the manufacture of light-weight aggregates and processed to form ceramic pellets. A formula uniform design was performed to arrange the mixture ratio of the materials. The optimal mixture ratio of the materials was determined by measuring the bulk density, granule strength, and 1 h water absorption of the pellets. It is shown that the optimal mixture ratios of materials, MSWI fly ash, shale, and sludge, are 23.16%, 62.58%, and 14.25% （mass fraction）, respectively. The performance testing indicators of light-weight aggregates are obtained under the optimum mixture ratio： bulk density of 613 kg/m3, granule strength of 821N, and 1 h water absorption of 11.6%, meeting 700 grade light-aggregate of GB/T 17431.2--1998 standard. The results suggest that utilization of MSWI fly ash in light-weight aggregates is an effective method and a potential means to create much more values.

关键词： MSWI fly ash pre-treatment trefoil rotary kiln heavy metal light-weight aggregates

Rapid, cost-effective DNA quantification via a visuallydetectable aggregation of superparamagnetic silicamagnetite nanoparticles

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Nano Research 2014年第5期7卷 755-764页

作者： Qian Liu jingyi Li Hongxue Liu Ibrahim Tora Matthew S. Ide jiwei Lu Robert j. Davis david L. green james P. Landers Department of Chemistry University of Virginia McCormick Road P. O. Box 400319 Charlottesville 22904 Virginia USA Department of Pathology University of Virginia Health Science Center Charlottesville 22908 Virginia USA Department of Mechanical Engineering University of Virginia Charlottesville 22904 Virginia USA Center for Microsystems forthe Life Sciences University of Virginia Charlottesville 22904 Virginia USA Department of Materials Science & Engineering University of Virginia P. O. Box 400745 395 McCormick Road Charlottesville 22904-4745 Virginia USA Department of Chemical Engineering University of Virginia. 123 Engineers Way Charlottesville 22904 Virginia USA

DNA and silica-coated magnetic particles entangle and form visible aggregates under chaotropic conditions with a rotating magnetic field, in a manner that enables quantification of DNA by image analysis. As a means of exploring the mechanism of this DNA quantitation assay, nanoscale SiO2-coated Fe304 （Fe3O4@SiO2） particles are synthesized via a solvothermal method. Characterization of the particles defines them to be -200 nm in diameter with a large surface area （141.89 m2/g）, possessing superparamagnetic properties and exhibiting high saturation magnetization （38 emu/g）. The synthesized Fe3O4@SiO2 nanoparticles are exploited in the DNA quantification assay and, as predicted, the nanoparticles provide better sensitivity than commercial microscale Dynabeads for quantifying DNA, with a detection limit of 4 kilobase-pair fragments of human DNA. Their utility is proven using nanoparticle DNA quantification to guide efficient polymerase chain reaction （PCR） amplification of short tandem repeat loci for human identification.

关键词： silica/magnetite core-shell superparamagnetic DNA quantification polymerase chain reaction(PCR)

Promoting green transformation by ensuring food security while reducing the environmental footprint of food and farming with agriculture green development

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维普期刊数据库

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 1-4,I0005页

作者： William j.DAVIES jianbo SHEN Lancaster Environment Centre Lancaster UniversityLancaster LA14YQUK State Key Laboratory of Nutrient Use and Management National Academy of Agriculture Green DevelopmentCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Reconciling the challenges of producing adequate amounts of nutritious food for the increasing global population while limiting environmental damage that can result from operations of our food systems is an enormous *** many parts of the world,agriculture is undergoing major transformations and this has been and still is particularly the case in China.

关键词： operations agriculture transformation

用于光纤射频传输系统的多量子井半导体激光器的非线性模型(英文)

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用于光纤射频传输系统的多量子井半导体激光器的非线性模型(英文)

Globodera pallida,a non-transgenic invertebrate as a new model for investigating Alzheimer’s disease(and other proteinopathies)?

“科技增强国力，青年开创未来——携手走向辉煌的新世纪”中国科协第三届青年学术年会

作者：梁可非潘琦 Roger j.green Dept.of EIMC University of BradtordUK

本文基于激光器数率方程和Volterra非线性理论,对多量子井(MQW)半导体激光器提出了包含量子捕获和逃溢过程的一个新的非线性模型。该模型从三个分别表示动态光子密度,限制区和阻挡层中的动态载流子密度及有源层(量子井)中的动态载流子... 详细信息

本文基于激光器数率方程和Volterra非线性理论,对多量子井(MQW)半导体激光器提出了包含量子捕获和逃溢过程的一个新的非线性模型。该模型从三个分别表示动态光子密度,限制区和阻挡层中的动态载流子密度及有源层(量子井)中的动态载流子密度变化的微分方程出发,利用Volterra理论分析,给出了激光器小信号频率响应,弛豫振荡频率(f)和二、三阶互调及交调失真分量,其结果表明:(1)弛豫振荡频率与偏置电流(I-I)/2曲线的斜率不为常数,而是随偏置增加而逐渐减小,这一结果与实验数据相吻合,特别是在高偏置范围内,(2)三阶交调失真有一最小值,因而可随偏置电流优化。这个"落点"(dip)现象已在实验中有所报道,但没有被原有模型解释。

关键词：非线性失真多量子阱激光器 Volterra序列射频-光纤传输

来源： cnki会议评论

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cnki会议

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Neural Regeneration Research 2023年第1期18卷 113-114页

作者： Norah A.Althobaiti Farid Menaa johnathan j.Dalzell Brian D.green Biology Department College of Science and Humanities-Al QuwaiiyahShaqra UniversityAl QuwaiiyahSaudi Arabia Departments of Internal Medicine and Nanomedicine Fluorotronics-California Innovations CorporationSan DiegoCAUSA Department of grassland and Plant Science AgriFood and Biosciences InstituteNorthern IrelandUK Institute for Global Food Security School of Biological SciencesQueen’s University BelfastBelfastUK

Biological models of Alzheimer’s disease(AD):Non-human models have contributed tremendously to the understanding of AD and its underlying pathological *** models have aided the investigation of the genetic and environmental risk *** also have enabled the progression of candidate therapies into human clinical *** of similarities with human brain anatomy and genetics,rodent models have been used extensively to recapitulate some aspects of AD pathology,measure AD-associated behavioral parameters and related nervous system dysfunctions(Eriksen and janus,2007).For instance,transgenic mice overexpressing human amyloid precursor protein have furthered the development of the amyloid cascade hypothesis as a central pillar of familial AD.

关键词： anatomy Alzheimer amyloid

Influence of laser polarization on collective electron dynamics in ultraintense laser-foil interactions

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High Power Laser Science and Engineering 2016年第3期4卷 120-126页

作者： Bruno Gonzalez-Izquierdo Ross j.Gray Martin King Robbie Wilson Rachel j.Dance Haydn Powell david A.Mac Lellan john McCreadie Nicholas M.H.Butler Steve Hawkes james S.green Chris D.Murphy Luca C.Stockhausen david C.Carroll Nicola Booth Graeme G.Scott Marco Borghesi david Neely Paul McKenna SUPA Department of Physics University of Strathclyde Central Laser Facility STFC Rutherford Appleton Laboratory Department of Physics University of York Centro de Láseres Pulsados (CLPU) Centre for Plasma Physics Queens University Belfast

The collective response of electrons in an ultrathin foil target irradiated by an ultraintense(~6×10^(20)W cm^(-2)) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture', inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.

关键词： laser–plasmas interaction ultraintense ultrashort pulse laser interaction with matters