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evaluating the effectiveness of marine actinobacterial extract and its mediated titanium dioxide nanoparticles in the degradation of azo dyes

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Journal of environmental Sciences 2014年第4期26卷 775-782页

作者： S Priyaragini S Veena d Swetha l Karthik g Kumar K V Bhaskara Rao Molecular and Microbiology Research laboratory Environmental Biotechnology Division School of Bio Sciences and Technology VIT University

Aim of the present study was to synthesize titanium dioxide nanoparticles （YiO2 NPs） from marine actinobacteria and to develop an eco-friendly azo-dye degradation method. A total of five actinobacterial isolates were isolated from Chennai marine sediments, Tamilnadu, India and analyzed for the synthesis of TiO2 NPs using titanium hydroxide. Among these, the isolate PSV 3 showed positive results for the synthesis of TiO2 NPs, which was confirmed by UV analysis. Further characterization of the synthesized TiO2 NPs was done using XRd, AFM and FI＇-IR analysis. Actinobacterial crude extract and synthesized TiO2 NPs was found efficient in degrading azo dye such as Acid Red 79 （AR-79） and Acid Red 80 （AR-80）. degradation percentage was found to be 81% for AR-79, 83% for AR-80 using actinobacterial crude extract and 84% for AR-79, 85% for AR-80 using TiO2 NPs. Immobilized actinobacterial ceils showed 88% for AR-79 and 81% for AR- 80, dye degrading capacity. degraded components were characterized by FT-IR and gC-MS analysis. The phytotoxicity test with 500 μg/ml of untreated dye showed remarkable phenotypic as well as cellular damage to Tagetes erecta plant. Comparatively no such damage was observed on plants by degraded dye components. In biotoxicity assay, treated dyes showed less toxic effect as compared to the untreated dyes.

关键词： actinobacteria azo dye degradation ZiO2 NPs biotoxicity Tagetes erecta

High refractive index of melanin in shiny occipital feathers of a bird of paradise

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light(Science & Applications) 2015年第1期4卷 518-523页

作者： doekele g Stavenga Hein l leertouwer daniel C Osorio Bodo d Wilts Computational Physics University of Groningen9747 AGThe Netherlands School of life Sciences University of SussexBrightonBN19QGUK Adolphe Merkle Institute University of FribourgCH-1700 FribourgSwitzerland

Male lawes’s Parotia,a bird of paradise,use the highly directional reflection of the structurally colored,brilliant-silvery occipital feathers in their courtship *** in other birds,the structural coloration is produced by ordered melanin *** barbules of the Parotia’s occipital feathers,with thickness,3 μm,contain 6–7 layers of densely packed melanin rodlets(diameter,0.25 μm,length,2 μm).The effectively,0.2 μm thick melanin layers separated by,0.2 μm thick keratin layers create a multilayer interference *** measurements yielded peak wavelengths in the near-infrared at,1.3 μm,i.e.,far outside the visible wavelength *** the Jamin-lebedeff interference microscopy method recently developed for pigmented media,we here determined the refractive index of the intact *** thus derived the wavelength dependence of the refractive index of the barbules’melanin to be 1.7–1.8 in the visible wavelength *** the anatomical and refractive index data in an optical multilayer model,we calculated the barbules’reflectance,transmittance and absorptance spectra,thereby confirming measured spectra.

关键词： bird of paradise interference reflector iridescence Jamin-lebedeff microscopy multilayer

Simulation of dike-break processes in the Yellow River

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Science China(Technological Sciences) 2002年第6期45卷 606-619页

作者：梁林倪晋仁 A.g.l.Borthwick B.d.Rogers department of environmental engineering Peking University Beijing 100871 China The Key laboratory of Water and Sediment Sciences Ministry of Education Beijing 100871 China

Although dike-break and dam-break processes have similar unsteady and discontinuous hydrodynamic characteristics, there are significant differences. In general, dam-break simulations focus on the flood discharge, whereas dike-break simulations are required to provide detailed information on the hydraulic and breach evolution processes, such as pit-scour and breach-expansion. In order to overcome the difficulties inherent in applying existing dam-break models to dike-breaks, this paper presents an integrated model that combines the shallow water, sediment transport, riverbed deformation and breach-expansion equations. A godunov-type finite volume method is used for the flow simulation, based on a fixed quadtree grid system. The hydrodynamic aspects of the model are validated for an idealized rectangular dam break. A representative reach in the Yellow River is selected at a location where there is a significant risk of a dike-break, and full-scale topographic and hydrologic data are available. Typical dike-break processes are successfully simulated, with predicted hydraulic characteristics and terrain changes qualitatively in agreement with laboratory data. The modeling study is of practical importance for implementation of engineering countermeasures in the Yellow River, such as breach blocking and head wrapping.

关键词： Yellow River dike-break shallow water godunov finite volume breach

Strength criterion of porous media: Application of homogenization techniques

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Journal of Rock Mechanics and geotechnical engineering 2017年第1期9卷 62-73页

作者： l. dormieux e. lemarchand d. Kondo S. Brach CNRS UMR 8205 ENPC Laboratoire Navier 6 et 8 avenue Blaise Pascal 77455 Marne-la-Vallée France UPMC Institut Jean le Rond d’Alembert Paris France

The present paper aims at giving some general ideas concerning the micromechanical approach of the strength of a porous material. It is shown that its determination theoretically amounts to solving a nonlinear boundary value problem defined on a representative elementary volume(ReV). The principle of nonlinear homogenization is illustrated based on the case of a solid phase having a green’s strength criterion. An original refinement of the so-called secant method(based on two reference strains) is also provided. The paper also describes the main feature of the gurson’s model which implements the principle of limit analysis on a conceptual model of hollow sphere. The last part of the paper gives some ideas concerning poromechanical couplings.

关键词： Strength criterion Porous media Homogenization techniques Nonlinear behavior limit analysis gurson’s model

energy and momentum of rotating frames in tetrad gravity

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Chinese Physics B 2011年第10期20卷 101-111页

作者： gamal g l Nashed Mathematics department Faculty of Science Ain Shams University

Within the framework of the tetrad formulation of general relativity theory, we compute the total energy and momentum of four rotating frames using the gravitational energy-momentum 3-form. We show how the effect of inertia always makes the total energy divergent. We use a natural regularization method to obtain physical values for the total energy of the system and show how it works on a number of explicit examples. We also show by calculation that inertia has no effect on the momentum components.

关键词： teleparallel gravity, energy-momentum WeitzenbSck connection, regularization telepar-allelism

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

exploring unconventional attributes of red blood cells and their potential applications in biomedicine

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Protein & Cell 2024年第5期15卷 315-330页

作者： Alkmini T.Anastasiadi Vasiliki-Zoi Arvaniti Krystalyn e.Hudson Anastasios g.Kriebardis Constantinos Stathopoulos Angelo d’Alessandro Steven l.Spitalnik Vassilis l.Tzounakas department of Biochemistry School of MedicineUniversity of Patras26504 PatrasGreece department of Pathology and Cell Biology Columbia University Irving Medical CenterNew York CityNY 10032USA laboratory of Reliability and Quality Control in laboratory Hematology(HemQcR) Department of Biomedical SciencesSchool of Health&Caring SciencesUniversity of West Attica(UniWA)12243 EgaleoGreece department of Biochemistry and Molecular genetics University of Colorado Anschutz Medical Campus13001 AuroraCOUSA Present address:Institute for Fundamental Biomedical Research(IFBR) Biomedical Sciences Research Center“Alexander Fleming”Vari11527 AthensGreece

We need to talk about red blood *** cells are defined as cells containing distinct nuclei and other membranous ***,red blood cells(RBCs)lack a nucleus and organelles—perhaps to limit the generation of reactive oxygen species(Zhang et al.,2011)—and are filled with hemoglobin(Hb).This oxygen carrier is limited to the cytosol by the cell membrane and cytoskeleton,which maintain cellular integrity and deformability as RBCs pass through narrow capillaries(gratzer,1994)to perform their primary function of gas exchange.

关键词： membranous maintain

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

APPlICATION OF A NOVel AlgORITHM FOR MOVINg SURFACe FlOWS

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Journal of Hydrodynamics 1997年第1期9卷 87-95页

作者： Xu Wei-xing, g. d. Raithby, g. d. Stubleydepartment of Mechanical engineering, University of Waterloo, Waterloo, Ontario, CanadaN2l3g1 Univ of Waterloo Waterloo Canada

Purpose:To demonstrate a novel algorithm for simulating moving surface flows. Methods: A fully conservative control volume method, on an adaptive eulerian grid, has been developed to guarantee that the 'kinematic free surface condition 'is automatically satisfied by solving the mass and momentum conservation equations. No separate free surface tracing equation is needed. The basic idea has been extended to solve general moving surface problems by adding 'boundary-node-constraints' to the solution equation set. Results; Two application problems, a critical free surface flow over an obstruction and flow past a 2-d inflated building, were predicted by the proposed method. The predicted results were in good agreement with the corresponding experimental findings. Conclusions: The proposed moving surface model permits prescribed moving walls, free surfaces, and compliant surfaces to be simulated by the same computer code. The moving surface shape is obtained as part of the solution of the conservation equations; no surface-tracing step is needed.

关键词： CFd simulation moving surface flows algorithm