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Solutions to the Modified Poschl-Teller Potential in d-dimensions

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Chinese Physics Letters 2010年第4期27卷 9-12页

作者： d. Agboola department of Pure and Applied Mathematics Ladoke Atdntola University of Technology Oyo State P.M.B. 4000 Nigeria

An approximate solution of the d-dimensional Schrodinger equation with the modified Posehl-Teller potential is obtained with an approximation of the centrifugal term. Solution to the corresponding hyper-radial equation is given using the conventional Nikiforov-Uvarov method. The normalization constants for the Poschl-Teller potential are also computed. The expectation values of 〈r^-2 and 〈V（r）〉 are also obtained using the Feynman- Hellmann theorem.

关键词： Quantum information and quantum mechanics

Aquatic community structure and stream habitat in a karst agricultural landscape

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Ecological Processes 2022年第1期11卷 155-170页

作者： Neal d.Mundahl Erik d.Mundahl department of Biology and Southeastern Minnesota Water Resources Center Winona State UniversityWinonaMN 55987USA Mundahl Nordic Services Glennallen/McCarthyP.O.Box MXYAlaska 99588USA

Background:Watersheds dominated by agriculture often have significant,negative impacts on local stream habitats and *** study examined stream biota and habitats within an entire stream in a karst agricultural landscape to determine if several decades of watershed conservation and management had reversed the severe degradation caused by poor land use and catastrophic soil erosion during the 1920s and ***:Fish communities and stream habitats were degraded at over half of the 22 stream sites examined,and benthic macroinvertebrate communities were mostly poor throughout the entire *** fish communities were associated with missing or narrow riparian buffers,high percent fine sediments,high embeddedness of coarse sub-strates,and homogeneous run *** communities were dominated by filter-feeding taxa and those adapted to life on or within fine *** sites with wide buffers and influenced by groundwater springs had higher fish community integrity and good to excellent instream ***:Our results suggest that wide riparian buffers and karstic springs may have allowed recovery of some stream reaches,but more extensive buffers and additional soil conservation practices in upland areas likely are necessary to protect most stream segments and their biota from on-going agricultural *** state stream buffer laws instituted after this study resulted in establishment of vegetated buffers at all study sites,which may lead to improved stream habitat and biotic communities in future *** invertebrate community improvement also may require translocation of sensitive taxa from nearby watersheds due to limited dispersal abilities of many species currently absent from the study *** frequency and intensity of storm events and flooding may hinder future recovery of stream habitats and biota.

关键词： Agricultural stream Fish Macroinvertebrates Stream habitats Karst

Sustainable oil-in-water analysis using a supercritical fluid carbon dioxide extraction system directly interfaced with infrared spectroscopy

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Journal of Environmental Sciences 2010年第9期22卷 1462-1468页

作者： Edward d.Ramsey School of Chemical Engineering University of Science and Technology Liaoning

A direct aqueous supercritical fluid extraction （SFE） system using carbon dioxide provides a sustainable means by which a vast range of industries may continue to depend on well established infrared （IR） techniques to determine oil-in-water. The SFE-IR method provides an environmentally friendly substitute for current national standard IR reference methods for measuring oil-in-water that rely on using increasingly restricted ozone depleting solvents whose manufacture is being phased out in accordance with international law. The SFE-IR analysis of a 500 mL water sample can be accomplished in 15 min. A rapid on-line SFE-IR calibration method has been implemented. With this calibration method, SFE-IR accuracy for determining diesel oil in 500 mL spiked water samples using single wave number measurement was 86.0%-98.8% with precision （RSd） ranging from 2.5%-7.0%. Using a general purpose calculation which involves measuring infrared absorbance values at three different wave numbers, SFE-IR method accuracy for determining diesel oil in 500 mL spiked water samples was 83.7%-92.2% with RSd 1.0%-9.3%. data is presented that indicates current long established national standard IR reference methods involving three wave number calculations should be reviewed since, without careful consideration, the inclusion of calculated aromatic hydrocarbon species contributions to final oil-in-water concentration values may provide less accurate results.

关键词： oil-in-water supercritical fluid extraction infrared spectroscopy sustainable green technology

New insight into the phylogenetic and biogeographic history of genus Ficus:Vicariance played a relatively minor role compared with ecological opportunity and dispersal

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Journal of Systematics and Evolution 2011年第6期49卷 546-557页

作者： Rhett d.HARRISON Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences

Studies on the evolution of tropical taxa emphasize the role of vicariance and the break-up of Gondwana in explaining modern *** studies on figs(Ficus spp.)support this *** the current study,we used an expanded sample(208 spp.)and improved molecular dating techniques to reconstruct the phylogenetic and biogeographic history of *** with previous studies,our biogeographic analysis indicated that the ancestor of Ficus was present in ***,a relaxed clock analysis relying on uncorrelated rates in BEAST suggested that the Neotropical section Pharmacosycea split-off in South America 86.67 Mya,and that other Ficus lineage ancestors originated in *** of the basal lineages appeared to have diverged following KT extinction,then rapidly diversified after India collided with continental *** Afrotropical species most likely evolved initially in the Indian subcontinent then dispersed to Africa,either in the late Cretaceous of Madagascar or even later,following the Eocene collision of India with *** Neotropical section Americana,either islandhopped to South America or took a northern route to the Americas through Europe prior to the terminal Eocene global cooling *** may have arrived in eastern Malesia following the collision of India with Asia,then widely dispersed *** the wide ranges in our date estimates,several other scenarios are ***,contrary to earlier reports,our analyses suggest that vicariance played a relatively minor role compared with ecological opportunity and dispersal in the diversification of genus Ficus.

关键词： biogeographic history evolution Ficus molecular phylogeny vicariance.

High level arsenic resistance in bacteria present in biooxidation tanks used to treat gold-bearing arsenopyrite concentrates:A review

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中国有色金属学会会刊：英文版 2008年第6期18卷 1311-1318页

作者： d.E.RAWLINGS department of Microbiology University of StellenboschPrivate Bag X1

在连续流动的、搅动的坦克过程使用到金忍受的毒砂集中的对待的微生物引起的协会变得在很多年适应了砷的高集中。主导的微生物， Acidithiobacillus caldus 和 Leptospirillum ferriphilum，被发现包含砷抵抗基因的二个集合。艺术基因... 详细信息

在连续流动的、搅动的坦克过程使用到金忍受的毒砂集中的对待的微生物引起的协会变得在很多年适应了砷的高集中。主导的微生物， Acidithiobacillus caldus 和 Leptospirillum ferriphilum，被发现包含砷抵抗基因的二个集合。艺术基因的一个集合在所有是在场的不管他们是否是，种孤立高度砷抵抗。艺术基因的第二个集合在象 Tn21 一样 transposons 上是在场的并且在测试的所有紧张被发现那被使适应了砷的高集中。在在场的砷抵抗 transposons 在。caldus 和 L。ferriphilum 为他们密切相关，却足够地不同独立地被获得了而非从一个细菌被传递了给其它。transposons 在 Escherchia coli 是置换地活跃的并且被显示比测试这是可能的定位 chromosomally 的艺术基因授与砷抵抗的高水平。相同的 Transposons 包含砷抵抗基因或仔细与从 L 的 transposon 有关。ferriphilum，原来在南非发现，也在两 L 被发现。ferrooxidans 和 L。ferriphilum 从南美洲和欧洲孤立。一个 arsB 基因大美人在。caldus 被两个都表明了 chromosomal 艺术基因的能力授与砷抵抗的底层在的相应再结合生产在。caldus 和为猛烈异种的创造的一个基因系统的发展。

关键词：砷电阻因子转座子微生物毒砂

development，Application，Markets，and　Patent　Situation　of　Magnetostrictive　TERFENOL－d

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Journal of Rare Earths 1995年第4期13卷 295-301页

作者： McMasters, O.d. ETREMA Products Inc. 2500 North Loop Drive Ames Iowa 50010

The development of the giant magnetostrictive rare earth-iron materials is reported from their discovery in the early 1970's to their present use in transducer and sensor applications. Fifteen broad market areas, ranging from miniature devices in the medical industry to high powder sonar and seismic sources have been identified. A world-wide customer base in these high technology fields has been established and the superior properties of these materials are responsible for the rapid growth of the magnetostrictive transducer industries. The critical design criteria that lead to efficient devices are reported and the performance of several of these products is presented. The key patents associated with these giant magnetostrictive materials and devices using these materials are reviewed. The present and future of these technologies in reference to commercialization, market growth and the impact on the many transduction industries are discussed. (Author abstract) 9 Refs.

关键词： Magnetostrictive Situation Patent TERFENOL and development Application

Biodiversity and interactions of acidophiles:Key to understanding and optimizing microbial processing of ores and concentrates

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中国有色金属学会会刊：英文版 2008年第6期18卷 1367-1373页

作者： d.B.JOHNSON School of Biological Sciences Bangor University

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，... 详细信息

采矿公司为从低档矿石恢复贱、宝贵的金属，并且为重新调停变得逐渐地知道 microbiological 途径的潜力从操作和放弃的矿地点排干的酸的、充满金属的废水。生物系统出现很多环境并且(有时) 超越常规途径的节俭的优点尽管他们的申请是，例如热冶学，别处于每种状况拨出。矿物质用微生物处理为提取黄金，铜，铀和钴被利用了，并且当前的开发正在指向另外的贱金属。最近，我们 biomining 环境，并且微生物怎么与对方一起交往的微生物学的差异的知识和理解有大增加。从模仿了搅动的坦克和堆生物反应器系统的实验室实验的结果证明了微生物引起的协会比氧化矿物质的 acidophiles 的纯文化更柔韧，并且也趋于在 bioleaching 和氧化简历的矿石更有效并且专注。纸论述了性质的简明评论和涉及硫化物矿物质的氧化的微生物引起的协会的相互作用，并且这些怎么可能被改编在 biomining 操作遇见未来挑战。

关键词：嗜酸细胞生物采矿生物多样性微生物加工

Passive electrochemical hydrogen recombiner for hydrogen safety systems:prospects

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Nuclear Science and Techniques 2023年第6期34卷 215-224页

作者： A.V.Avdeenkov d.G.Bessarabov d.G.Zaryugin All Russian Research Institute for Nuclear Power Plants Operation JSC 25 Ferganskaya Str.MoscowRussia109507 HySA Center Faculty of EngineeringNorth-West UniversityPotchefstroom2520South Africa State Atomic Energy Corporation Rosatom 24 Bolshaya Ordynka Str.MoscowRussia119017

This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design *** experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(MEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were *** simplest MEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.

关键词： Recombiner Catalytic ignition Hydrogen explosion safety Hydrogen fuel cell Membrane electrode assembly

Coating particles using liquids and foams based on viscous formulations with industrial mixers: Batch operation

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Particuology 2020年第3期18卷 13-24页

作者： d.Kontziampasis M.S.Manga d.W.York School of Chemical and Process Engineering Faculty of EngineeringUniversity of LeedsLS29JTLeedsW.YorkshireUK

Particle or powder coating with viscous liquids has been essential in industry for surface modification purposes to induce and enhance specific *** paper evaluates the performance of using foams (of different bubble diameters) versus liquids as a means of coating powder beds based on viscous liquid *** with viscous liquids present numerous industrial challenges and therefore preparing foam equivalents can render the liquid component weak enough (through pre shearing to form the foam),to allow it to break up and coat particles under the shear forces exerted in a mixing *** this study,two shear mixers are used;the first type consists of paddles in different configurations attached to a single rotating shaft,whilst the second type is a commercial twin screw mixer (TSM).The quality of coating achieved on the bulk powder bed using liquids and foams (stained with a dye) is assessed by image analysis to determine the homogeneity of the color *** addition,scanning electron microscopy provides a tool to further investigate the coating quality of individual particles from the bulk *** results show that large bubble (centimeter size) foams are much more effective at distributing within the fluidized powder bed compared to the starting viscous liquid and small bubble foams (submillimeter size).Furthermore,there is a maximum ratio of foam to powder beyond which agglomeration occurs and is insufficient to fully coat the *** of individual particles is achieved in the case of the TSM,whereas SEM proves that the single shaft paddle mixer crushes the particles and subsequently granulates them together to form granules of a size comparable to the size of coated particles seen after coating with the TSM.

关键词： Powder coating Viscous liquid Foam Image analysis Foam rheology Surface modification