检索结果-南通市图书馆

blasius flow and heat transfer of fourth-grade fluid with slip

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2013年第12期34卷 1465-1480页

作者： b.s.HOO s.PONCET Department of Mathematics National Institute of Technology Laboratoire de Mecanique Modelisation and Procedes PropresAix-Marseille Universite

This investigation deals with the effects of slip, magnetic field, and non- Newtonian flow parameters on the flow and heat transfer of an incompressible, electrically conducting fourth-grade fluid past an infinite porous plate. The heat transfer analysis is carried out for two heating processes. The system of highly non-linear differential equations is solved by the shooting method with the fourth-order Runge-Kutta method for moderate values of the parameters. The effective broyden technique is adopted in order to improve the initial guesses and to satisfy the boundary conditions at infinity. An exceptional cross-over is obtained in the velocity profile in the presence of slip. The fourth-grade fluid parameter is found to increase the momentum boundary layer thickness, whereas the slip parameter substantially decreases it. similarly, the non-Newtonian fluid parameters and the slip have opposite effects on the thermal boundary layer thickness.

关键词： blasius flow partial slip fourth-grade fluid shooting method broyden'smethod

Invasion syndromes:hypotheses on relationships among invasive species attributes and characteristics of invaded sites

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2013年第3期5卷 275-283页

作者： Lora b PERKINs Robert s NOWAK Department of Natural Resource Management South Dakota State UniversityBrookings SD 57007USA Department of Natural Resources & Environmental science University of NevadaReno NV 89557USA

As invasion science accepts that there is no single causal factor for biological invasion, the identification of groups of traits that are often associated, or ＂syndromes＂, is a logical move forward. Invasion syndromes are proposed to identify suites of site conditions （biotic and environmental） that render a site vulnerable to invasion by different types of invaders. This paper proposed four invasion syndromes which relate invader attributes （competitive ability, niche construction, phenotypic plasticity, and phenological niche separation） to the biotic characteristics （biodiversity and enemies） and environmental conditions （resource abundance and fluctuation） of invaded sites. The four invasion syndromes described in this paper are a development of hypotheses of how the many factors that influence species invasion might be associated. Invasion syndrome 1 proposes that sites with relatively high resource abundance and high diversity should be vulnerable to invasion by species with high competitive ability. Invasion syndrome 2 hypothesizes that sites with relatively low resource abundance and low diversity should be vulnerable to invasion by species with niche construction ability. Invasion syndrome 3 postulates that sites with moderate or fluctuating resources and moderate diversity should be vulnerable to invasion by species with high phenotypic plasticity. Invasion syndrome 4 hypothesizes that species introduced into a site where it has phenological niche separation from natives will not have to contend with interference from the biotic community at a site （diversity or natural enemies） and may invade where ever site environmental conditions suit its life history. Further work is needed to support, contradict, or refine these hypotheses and almost certainly will identify more invasion syndromes.

关键词： non-native competitive ability niche construction ecosystem engineering phenotypic plasticity phenological niche separation

Consequence of exponential heat generation on non-Darcy- Forchheimer flow of water b.s.d carbon nanotub.s.driven by a curved stretching sheet

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2020年第11期41卷 1723-1734页

作者： b.J.GIREEsHA b.NAGARAJA s.sINDHU G.sOWMYA Department of P.G.studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India

The present article comprises the study on the influence of exponential space b.s.d heat generation on the non-Darcy-Forchheimer flow of carbon nanotub.s.CNTs).The flow is considered over a curved stretching *** variables are used to reduce the flow descriptive nonlinear partial derivative equations to simple *** equations are then solved by the exploiting Runge-Kutta-Fehlberg fourth-and fifth-order *** numerical solutions are shown in graphs and *** between single and multi-walled CNTs has been established through the tabulated values and plotted *** is concluded that the heat source parameter plays a prime role in enhancement of temperature,and the curvature parameter has adverse impact on velocity and temperature *** the inertial parameter and inverse-Darcy number affect the fluid velocity.

关键词： exponential heat generation non-Darcy-Forchheimer flow carbon nanotube(CNT) curved stretching sheet

DeNOx study in Diesel Engine Exhaust Using barrier Discharge Corona Assisted by V_2O_5/TiO_2 Catalyst

在线全文

学校读者我要写书评

暂无评论

Plasma science and Technology 2004年第4期6卷 2411-2415页

作者： b.s.Rajanikanth V.Ravi Indian Institute of science Bangalore 560012IndiaIndian Institute of ScienceBangalore 560012India

A plasma-assisted catalytic reactor was used to remove nitrogen oxides (NOx)from diesel engine exhaust operated under different load conditions. Initial studies were focused onplasma reactor (a dielectric barrier discharge reactor) treatment of diesel exhaust at varioustemperatures. The nitric oxide (NO) removal efficiency was lowered when high temperature exhaust wastreated using plasma reactor. Also, NO removal efficiency decreased when 45% load exhaust wastreated. studies were then made with plasma reactor combined with a catalytic reactor consisting ofa selective catalytic reduction (sCR) catalyst, V_2O_5/TiO_2. Ammonia was used as a reducing agentfor sCR process in a ratio of 1:1 to NOx. The studies were focused on temperatures of the sCRcatalytic reactor below 200℃. The plasma-assisted catalytic reactor was operated well to remove NOxunder no-load and load conditions. For an energy input of 96 J/l, the NOx removal efficienciesobtained under no-load and load conditions were 90% and 72% respectively at an exhaust temperatureof 100 ℃.

关键词： non-thermal plasma DeNOx barrier discharge diesel exhaust

Upgradation of bauxite by molecular hydrogen and hydrogen plasma

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第10期23卷 1141-1149页

作者： b.R.Parhi s.K.sahoo s.C.Mishra b.bhoi R.K.Paramguru b.K.satapathy Department of Metallurgical and Materials Engineering National Institute of Technology Rourkela 769008 Odisha India Institute of Minerals and Materials Technology Bhubaneswar 751013 Odisha India Kalinga Institute of Industrial Technology Bhubaneswar 751024 Odisha India National Aluminium Company Ltd. Bhubaneswar 751013 Odisha India

An approach was developed to upgrade the bauxite ore by molecular hydrogen and hydrogen plasma. A gib.s.te-type bauxite sample was obtained from National Aluminium Company（NALCO）, Odisha, India. The obtained sample was crushed and sieved（to 100 μm） prior to the chemical analysis and grain-size distribution study. The bauxite sample was calcined in the temperature range from 500 to 700°C for different time intervals to optimize the conditions for maximum moisture removal. This process was followed by the reduction of the calcined ore by molecular hydrogen and hydrogen plasma. Extraction of alumina from the reduced ore was carried out via acid leaching in chloride media for 2 h at 60°C. X-ray diffraction, scanning electron microscopy, thermogravimetry in conjunction with differential scanning calorimetry, and Fourier transform infrared spectroscopy were used to determine the physicochemical characteristics of the material before and after extraction. Alumina extracted from the reduced ore at the optimum calcination temperature of 700°C and the optimum calcination time of 4 h is found to be 90% pure.

关键词： upgrading bauxite calcination leaching alumina extraction

A Cascaded Discharge plasma—Adsorbent Technique for Engine Exhaust Treatment

在线全文

学校读者我要写书评

暂无评论

Plasma science and Technology 2003年第3期5卷 1825-1833页

作者： b.s.Rajanikanth A.D.srinivasan b.AryaNandiny DeptofHighVoltageEngineering IndianInstituteofScienceBangalore560012India

A cascaded system of electrical discharges (non-thermal plasma) andadsorption process was investigated for the removal of oxides of Nitrogen (NO_x) and totalhydrocarbons (THC) from an actual diesel engine exhaust. The non-thermal plasma and adsorptionprocesses were separately studied first and then the cascaded process was studied. In this study,different types of adsorbents were used. The NO_x removal efficiency was higher withplasma-associated adsorption (cascaded) process compared to the individual processes and the removalefficiency was found almost invariant in time. When associated by plasma, among the adsorbentsstudied, activated charcoal and Ms-13X were more effective for NO_x and THC removal *** experiments were conducted at no load and at 50 % load conditions. The plasma reactor was keptat room temperature throughout the experiment, while the temperature of the adsorbent reactor wasvaried. A relative comparison of adsorbents was discussed at the end.

关键词： discharge plasma engine exhaust adsorbent non-thermal plasma

Coastal transgression and regression from 1980 to 2020 and shoreline forecasting for 2030 and 2040,using DsAs along the southern coastal tip of Peninsular India

在线全文

学校读者我要写书评

暂无评论

Geodesy and Geodynamics 2022年第6期13卷 585-594页

作者： s.Chrisben sam b.Gurugnanam Centre for Applied Geology The Gandhigram Rural Institute Deemed to be UniversityDindigulTamil NaduIndia

This study explains the multi-decadal shoreline changes along the coast of Kanyakumari from 1980 *** shorelines are extracted from the Landsat images to estimate the shoreline dynamics and future predictions using Digital shoreline Analysis system(DsAs).by the estimation of End Point Rate(EPR)and Linear Regression Rate(LRR),it is quantified that the maximum erosion is 5.01 m/yr(EPR)and 6.13 m/yr(LRR)consistently with the maximum accretion of 3.77 m/yr(EPR)and 3.11 m/yr(LRR)along the entire coastal stretch of 77 *** future shoreline predicted using the Kalman filter forecasted that Inayam,Periyakattuthurai and Kodimunai are highly prone to erosion with a shift of 170 m,157 m and 145 m by 2030 and 194 m,182 m and 165 m by 2040 towards the ***,the western coast is highly prone to erosion and it is predicted that certain villages are prone to loss of economy and *** outcome of this study may guide the coastal researchers to understand the evolution and decisionmakers to evolve with alternative sustainable management plans in the future.

关键词： shoreline change rates Future prediction DsAs Kalman filter Erosion and accretion

Chloride binding and time-dependent surface chloride content models for fly ash concrete

在线全文

学校读者我要写书评

暂无评论

Frontiers of structural and Civil Engineering 2016年第1期10卷 112-120页

作者： s. MUTHULINGAM b. N. RAO Department of Civil Engineering SSN College of Engineering Kalavakkam 603 110 India structural Engineering Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely： 1） surface chloride content under tidal exposure condition; and 2） chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed b.s.d upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms chloride ingress concrete fly ash surface chloride content

Nuclear structure and decay modes of Ra isotopes within an axially deformed relativistic mean field model

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2018年第8期42卷 121-129页

作者： Rashmirekha swain s.K.Patra b.b.s.hu school of Applied sciences KIIT Deemed to be UniversityBhubaneswar-751024OdishaIndia Institute of Physics Bhubaneswar-751005India

We examine the structural properties and half-life decay of Ra isotopes within the axially deformed Relativistic Mean-Field（RMF）theory with NL3 force *** work out the binding energy（bE）,RMs radii,two-neutron separation energies（s（2n））,and some other *** results are in good agreement with the finite-range droplet model（FRDM）and experimental *** the possibility of neutron magic number,theα-decay and cluster decay half-lives of Ra isotopes are calculated systematically using the Q-values obtained from the RMF *** decay half-life calculations are carried out by taking three different empirical *** calculated decay half-lives are found to be highly sensitive to the choice of *** shell or sub.s.ell closures are found at daughter nuclei with N=128 and N=126 when alpha and 8be,12C,18O respectively are emitted from Ra *** the cluster radioactivity is affected by the shell closure of parent and daughter,a long half-life indicates the stability of the parent,and a small parent half-life indicates that the shell stability of the daughter against decay.

关键词： relativistic mean field nuclear bulk properties alpha and cluster decay half-life