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Climate Change and Environmental Impact Caused by Anthropogenic

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Journal of Environmental Science and Engineering(b) 2012年第5期1卷 668-672页

作者： Omar Khodjet Kesba Mustapha kamel Mihoubi Abdelhamid Hebbouche Laboratory of Water Sciences National School for Hydraulics Blida 09000 Algeria

For the last two decades the world has undergone a population explosion which has been accompanied by a speeding up of urbanization and land use for industrial and agricultural products. These involve a vast increase in the discharge of pollutants into very different receiving water bodies, and have had adverse effects on the various components of the environment. For a long time, human has concerned a little of the natural environment. It is obvious that this variation in surface temperature of the earth increases the level of sea due to snowmelt. So climate change is manifested by many phenomena： floods, droughts, fires, tornadoes, cyclones, earthquakes, volcanic eruptions, diseases etc.. The statement today is dramatic. Entire regions were devastated and many rivers and lakes have become polluted around the world. Pollution has it nature which is hard to be absorbed. Where did the different pollutants come from？ What are the risks to the aquatic environment？ To prevent and combat the general decline of these ecosystems, it is important to distinguish and determine the effects of different sources of pollution and any changes that may suffer the physical environment. The climate depends primarily on changes in earth orbit parameters, which affect the solar radiation received by the earth surface. Therefore, human participates strongly to these changes, for example, pollution is the main reason to argue the greenhouse effect, an increase of anthropogenic carbon dioxide （CO2） into the atmosphere, which promotes global warming to the planet. These modifications are already applied in order to ensure durable development in water resources by controlling discharges into streams to preserve water resources for future generations and to ensure reconciliation between man-climate and environment.

关键词： Human climate environment anthropogenic pollution soil water.

Generating a New Higher-Dimensional Coupled Integrable Dispersionless System:Algebraic Structures,bcklund Transformation and Hidden Structural Symmetries

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Communications in Theoretical Physics 2013年第8期60卷 145-149页

作者： Souleymanou Abbagari Thomas b.bouetou Timoleon C.Kofane National Advanced School of Engineering University of Yaounde IP.O.Box 8390Cameroon Department of Physics Faculty of ScienceUniversity of Yaounde IP.O.Box 812Cameroon The Max Planck Institute for the Physics of Complex Systems Nthnitzer Strasse 3801187 DresdenGermany

The prolongation structure methodologies of Wahlquist-Estabrook [H.D. Wahlquist and F.b. Estabrook, J. Math. Phys. 16 （1975） 1] for nonlinear differential equations are applied to a more general set of coupled integrable dispersionless system. based on the obtained prolongation structure, a Lie-Algebra valued connection of a closed ideal of exterior differential forms related to the above system is constructed. A Lie-Algebra representation of some hidden structural symmetries of the previous system, its biicklund transformation using the Riccati form of the linear eigenvalue problem and their general corresponding Lax-representation are derived. In the wake of the previous results, we extend the above prolongation scheme to higher-dimensional systems from which a new （2 ＋ 1）-dimensional coupled integrable dispersionless system is unveiled along with its inverse scattering formulation, which applications are straightforward in nonlinear optics where additional propagating dimension deserves some attention.

关键词： coupled integrable dispersionless system algebraic structures b^cklund transformation Hiddenstructural symmetries

Dedicated to Professor Dr.-Ing. ***.h.c. Jurgen Zierep for his 80^(th) birthday Pattern Formation in Rotating Fluids

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Journal of Thermal Science 2009年第2期18卷 109-118页

作者： Karl bühler Department of Mechanical and Process Engineering University of Applied Sciences

Flows in nature and technology are often associated with specific structures and pattern. This paper deals with thedevelopment and behaviour of such flow pattern. Flow structures are important for the mass, momentum and energytransport. The behaviour of different flow pattern is used by engineers to obtain an efficient mass and energyconsumption. Mechanical power is transmitted via the momentum of rotating machine parts. Therefore thephysical and mathematical knowledge of these basic concepts is important. Theoretical and experimental investigationsof principle experiments are described in the following. We start with the classical problem of the flowbetween two concentric cylinders where the inner cylinder rotates. Periodic instabilities occur which are calledTaylor vortices. The analogy between the cylindrical gap flow, the heat transfer in a horizontal fluid layer exposedto the gravity field and the boundary layer flow along concave boundaries concerning their stability behaviour isaddressed. The vortex breakdown phenomenon in a cylinder with rotating cover is also described. A generalizationto spherical sectors leads then to investigations with different boundary conditions. The spherical gap flowexhibits interesting phenomena concerning the nonlinear character of the Navier-Stokes equations. Multiple solutionsin the nonlinear regime give rise to different routes during the laminar-turbulent transition. The interactionof two rotating spheres results in flow structures with separation and stagnation lines. Experimental results areconfirmed by numerical simulations.

关键词： Rotating Fluids Stability behaviour bifurcation Vortices Laminar-turbulent Transition

Evaluation of gravimetric sampler bias, effect on measured concentration, and proposal for the use of harmonised performance based dust sampler for exposure assessment

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International Journal of Mining Science and Technology 2019年第3期29卷 445-452页

作者： b.belle Anglo American Coal UNSW SydneyAustralia

The last three years has brought about alarming news of re-identification of coal worker’s pneumoconiosis(CWP)or‘black lung’in Australia after reporting nearly being absent for over five ***,the CWP statistics in South Africa(SA)are unverifiable,but certainly CWP has not been *** events have re-kindled the need for better understanding of the dust monitoring,performance of sampling devices,and compliance *** the last half century,gravimetric sampling has been the fundamental means for dust exposure monitoring using recognised respirable size-selective *** both South Africa and Australia,the gravimetric sampling technique in coal mines has been followed since 1988 and 1983 respectively using samplers of original Higgins-Dewell(HD)type *** paper provides the evaluation results of currently used South African and Australian gravimetric samplers compared against the original UK SIMPEDS‘true reference’*** results consistently suggested that the South African and Australian cyclones do not conform to the required size selective curve or even the‘true’reference *** results show that the currently used SA and Australian samplers showed a D50 sampling bias as high as 59%and 47%respectively against the size-selective ***,under the controlled laboratory coal dust test conditions measuring the same coal mine dust level in a chamber,the South African,Australian and UK standard SIMPEDS sampler were 7.87,9.79 and 6.71 mg/m3 respectively,which aligned with the sampling *** differences can in part be attributed to the‘un-auditable’inherent design and manufacturing quality,or unverifiable data on sizeselective sampling *** finding has significant implications towards exposure data collected over the last 25 years and their subsequent use in the arrival of the dose-response ***,it is strongly recommended that the harmonised use of‘true reference’SIMPEDS cyclone that meets the IS

关键词： Dust Respirable Sampling

Irreversibility investigation of Casson fluid flow in an inclined channel subject to a Darcy-Forchheimer porous medium:a numerical study

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 95-108页

作者： A.ROJA b.J.GIREESHA b.NAGARAJA Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShimoga 577451KarnatakaIndia

The heat transfer and entropy generation characteristics of the magnetohydrodynamic Casson fluid flow through an inclined microchannel with convective boundary conditions are ***,the effects of the viscous forces,Joule heating,heat source/sink,and radiation on the flow are taken into *** non-dimensional transformations are used to solve the governing ***,the reduced system is resolved by the fourth-fifth order Runge-Kutta-Fehlberg method along with the shooting *** effects of different physical parameters on the heat transfer and entropy generation are discussed in detail through *** the perspective of numerical results,it is recognized that the production of entropy can be improved with the Joule heating,viscous dissipation,and convective heating *** is concluded that the production of entropy is the maximum with increases in the Casson parameter,the angle of inclination,and the Hartmann *** the Reynolds number and the radiation parameter cause the dual impact on entropy generation.

关键词： inclined channel Casson fluid magnetism radiation entropy generation bejan number

How relevant are engineering samples in the management of personal dust exposure?

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International Journal of Mining Science and Technology 2018年第4期28卷 697-703页

作者： b.belle Anglo American Coal BrisbaneQueenslandAustralia Department of Mining Engineering UNSWSydneyNSW 2052Australia

A directive, legislated by the South African Department of Minerals and Energy(DME) in 1997, was introduced to reduce the dust exposures of continuous miner(CM) operators to below 5 mg/m3, when measured at the operator's cab position. The focus of this paper is to review the effectiveness of observing this rule for almost two decades and discuss industry perceptions arising from the application of this rule. The results have demonstrated that the engineering sample cannot predict the personal shift dust exposure of a CM operator. Therefore, it is recommended that the engineering sampling, as currently practiced,should be reviewed with the objective to discontinue and replace it by the approved PDM3700 realtime dust monitor.

关键词： Continuous miner (CM) Dust exposure Personal Engineering sample

Identification of the normal and abnormal glow discharge modes in a neon-xenon gas mixture at low pressure

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Plasma Science and Technology 2018年第11期20卷 70-75页

作者： b HECHELEF A bOUCHIKHI University of Saida Faculty of Technology Department of Electrical Engineering Saida 20000 Algeria

In this paper, we focused on the identification of the normal and abnormal glow discharge modes in a neon-xenon gas mixture at low pressure. We considered four gas mixtures： 90%Ne-10%Xe, 80%Ne-20%Xe, 70%Ne-30%Xe and 50%Ne-50%Xe at 1.5 Torr. The range of the gap voltage is 150-500 V. A one-dimensional fluid model with multiple species was used in this work, and the metastable state of the atoms as well as the radiation effects were integrated into the model too. The input data changed for each percentage in the gas mixture, and was calculated by bOLSIG＋ software. The parameters of particle transport and their rate coefficients strictly depend on the mean electron energy. The results show that the neon ion density is negligible compared to the xenon ion density, mostly in the case of 50%Ne-50%Xe.

关键词： gas mixtures boltzmann's equation Poisson's equation blanc's law two-order fluid model

Oscillating multidromion excitations in higher-dimensional nonlinear lattice with intersite and external on-site potentials using symbolic computation

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Chinese Physics b 2014年第1期23卷 98-107页

作者： b. Srividya louiskavitha@yahoo.co.in Department of Chemistry Periyar University Salem 636 011 India

We show by an extensive method of quasi-discrete multiple-scale approximation that nonlinear multi-dimensional lattice waves subjected to intersite and external on-site potentials are found to be governed by （N＋ 1 ）-dimensional nonlinear Schr6dinger （NLS） equation. In particular, the resonant mode interaction of （2＋l）-dimensional NLS equation has been identified and the theory allows the inclusion of transverse effect. We apply the exponential function method to the （2＋ I ）- dimensional NLS equation and obtain the class of soliton solutions with a purely algebraic computational method. Notably, we discuss in detail the effects of the external on-site potentials on the explicit form of the soliton solution generated recursively. Under the action of the external on-site potentials, the model presents a rich variety of oscillating multidromion patterns propagating in the system.

关键词： solitons partial differential equations lattice dynamics exact solutions

Genes for resistance to stripe rust on chromosome 2b and their application in wheat breeding

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Progress in Natural Science:Materials International 2009年第1期19卷 9-15页

作者： Peigao Luo a,b,Xueyun Hu a,Huaiyu Zhang a,Zhenglong Ren a,b,a State Key Laboratory of Plant breeding and Genetics,Sichuan Agriculture University,Ya’an,Sichuan 625014,China b School of Life Science and Technology,University of Electronic Science and Technology of China,Chengdu 610054,China [a]State Key Laboratory of Plant breeding and Genetics Sichuan Agriculture University Ya’an Sichuan 625014 China [b]School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Stripe rust,caused by Puccinia striiformis ***,is one of the most damaging diseases of wheat *** resistant cultivars is the most economic and environmental friendly way to control the *** are many resistance genes to stripe rust located on wheat chromosome ***,we propose a strategy to construct the recombinant wheat chromosome 2b with multiple resistances to stripe rust by making crosses between wheat lines or cultivars carrying Yr genes and using marker-assisted selection,based on the reported information about resistance spectrum,chromosomal location,and linked markers of the *** the resistance genes on 2b would afford a valuable strategy to control the disease by cultivating varieties with durable *** possibility,efficiency,and prospect of the suggested strategy are reviewed in the paper.

关键词： Puccinia striiformis Yr gene 2b chromosome Stripe rust Marker-assisted selection