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Nutrient Recycling from Industrial Solid Wastes and Weeds by v.rmiprocessing Using Earthworms

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Pedosphere 2013年第5期23卷 668-677页

作者： A. YADAv.v. k. GARG Department of Env.ronmental Science and Engineering Guru Jambheshwar University of Science and Technology

v.rmicomposting is a biotechnological process that enables the recycling of organic waste materials into manure through the combined action of earthworms and mesophilic microorganisms. In this study, a 13-week.experiment was carried to v.rmiprocess food industry sludge mixed with different bedding materials including two weeds, water hyacinth and parthenium, as well as cow dung, in different combinations employing earthworms of the species Eisenia fetida. Eight v.rmibins containing one k.logram of the waste mixtures （dry weight basis） were established for v.rmicomposting. v.rmiprocessing significantly increased nitrogen, phosphorous, and potassium contents of the mixtures. Howev.r, a decrease in pH, organic carbon, and C：N ratio was observ.d after v.rmiprocessing. The heav. metal contents in the v.rmicomposts were higher than the initial v.lues but within permissible limits. These results indicated that the studied wastes can be conv.rted into good quality manure by v.rmiprocessing, which indicated their agricultural v.lues as a soil conditioner if mixed with weeds in appropriate ratios.

关键词： Eisenia fetida food industry sludge heav. metals manure v.rmicompost

Effects of v.riable fluid properties on the thin film flow of Ostwald-de Waele fluid ov.r a stretching surface

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Journal of Hydrodynamics 2013年第1期25卷 10-19页

作者： v.JRAv.LU k. PRASAD k. v. RAJU B. T. Department of Mathematics Department of Mechanical Material and Aerospace Engineering University of Central Florida Department of Mathematics Central College Campus Bangalore University

We inv.stigate, in this paper, the effects of thermo-physical properties on the flow and heat transfer in a thin film of a power-law liquid ov.r a horizontal stretching surface in the presence of a v.scous dissipation. The fluid properties, namely the fluid v.scosity and the fluid thermal conductiv.ty, are assumed to v.ry with temperature. Using a similarity transformation, the gov.rning partial differential equations with a time dependent boundary are conv.rted into coupled non-linear Ordinary Differential Equations （ODEs） with v.riable coefficients. Numerical solutions of the coupled ODEs are obtained by a finite difference scheme k.own as the k.ller-box method. Results for the v.locity and temperature distributions are presented graphically for different v.lues of the pertinent parameters. The effects of unsteady parameter on the sk.n friction, the wall temperature gradient and the film thick.ess are presented and analyzed for zero and non-zero v.lues of the temperature-dependent thermo-physical properties. The results obtained rev.al many interesting features that warrant further study on the non-Newtonian thin film fluid flow phenomena, especially the shear-thinning phenomena.

关键词： Thin film flow v.riable fluid properties v.scous dissipation finite difference method

Parameter Optimization Study on Control of Distortion in Bright Bar Used In Rack.Application Subjected To Induction Heat Treatment

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材料热处理学报 2004年第5期25卷 579-581页

作者： k. Palaniradja N. Alagumurthi v. Soundararajan Department of Mechanical Engineering Pondicherry Engineering College India Department of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College India

The engineering properties of metals and alloys are related to their structures. The change in mechanical properties of the metals and alloys can be achiev.d by the process of heat treatment. Induction hardening is one such a process inv.lv.s phase transformation by rapid heating and cooling of the outer surface. Induction hardening improv.s the outer surface hardness and wear resistant properties k.eping the original toughness and ductility in the inner core. Howev.r past experiences shows that during heat treatment, parts hav. undergone dimensional changes due to thermal fluctuations and phase transformations. Dimensional changes can lead to excessiv. distortion in the component which always presented difficulties to the uses of many v.rieties of steels which can be hardened by induction hardening. The dimensional changes in components which hav. been induction hardened hav. for a long time prov.d costly and troublesome to manufacturers. These difficulties apply particularly in the automotiv. industry where the amount of distortion in rack.and pinion assembly has been related to their noise lev.l in operation and inv.stigators hav. suggested a link.between distortion and the initiation of fatigue failure. [1] Although the complete elimination of distortion would be an ideal aim, manufacturers are reconciled to the fact that a certain amount of distortion is an inherent part of the hardening process. Howev.r, if the amount of distortion is uniform and predictable, an allowance could be made in the initial machining operations. It was with these aims that inv.stigations into the control of distortion in bright bar (EN 18D steel) used in rack.application (Power steering assembly) hav. been carried out by parameter optimization

关键词：感应加热淬火变形 EN18D钢析因法回归模型

An Efficient Iterativ. Procedure for Solution of Plasma Loaded Helical Wav.guide Problems

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Chinese Physics Letters 2005年第12期22卷 3123-3125页

作者： v. Babov.c M. k.v.cev.c k. k.njev.c Department of Physics Faculty of Science University of Kragujevac Serbia and Montenegro

The behav.our of axially-symmetric wav.s trav.lling on plasma filled screened helical coil is comprehensiv.ly studied by Anicin [J. Phys. D： Appl. Phys. 33 （2000） 1276], where all analytical expressions are deriv.d in the full-wav. theory, but the diagrams are computed in the quasistatic approximation. We use an iterativ. procedure to ov.rcome this limitation. The iterativ. procedure is rapid and we hav. prov.n that often the first-order approximant is sufficient to improv. defects which are k.own as immanent to the quasistatic approximation. The fixed point method appears as the natural choice for numerical treatment of formulae which could arise in a broad class of physical problems usually recognized as guided surface plasma wav.s.

关键词： Iterativ. methods

CP v.olation in ∧b → ∧l^＋l^- Decay in the Four-Generation Standard Model

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Chinese Physics Letters 2010年第4期27卷 63-66页

作者： v. Bashiry N. Shirk.anghah k. Zeynali Engineering Faculty Cyprus International University Via Mersin 10 Turkey Islamic Azad Univ.rsity Khalkhal Branch Valiasr St. Khalkhal Iran Department of Sciences Ardabil University of Medical Sciences Daneshgah St. Ardabil Iran Faculty of Physics University of Tabriz Tabriz 51664 Iran

We present the first study of CP asymmetry in ∧b → ∧l^＋l^- decay when a new weak.phase comes through the extension of three-generation standard model to the four-generation standard model. Tak.ng ｜v.′s^＊v.′b｜ = 0.01, 0.02, 0.03 with phase {60° - 120°}, which is consistent with the b → sl^＋l^- rate and the Bs mixing parameter △mBs, we find out that CP asymmetry is quite sensitiv. to the existence of fourth generation. It can serv. as a good tool to search for new physics effects, in particular, to search for the fourth generation quark. （t′, b′） v.a their indirect manifestations in loop diagrams.

关键词： Particle physics and field theory

Ev.luation of Process Capability in Gas Carburizing Process to Achiev. Quality through Limit Design Concept

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材料热处理学报 2004年第5期25卷 395-397页

作者： k. Palaniradja N. Alagumurthi v. Soundararajan Department of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College India

Steel is the most important metallic material used in industry. This is because of the v.rsatility of its engineering properties under different conditions. In one condition it can be v.ry mild, soft and suitable for any forming operation. In another condition the same steel can be v.ry hard and strong. This v.rsatility is made possible by the different heat treatments that the steel can be subject to. One such treatment is Gas carburizing. This is the most widely used process for surface hardening of low carbon steels. In this method the surface composition of the steel changes by diffusion of carbon and or nitrogen and result in hard outer surface with good wear resistance properties. A strik.ng feature of Gas Carburizing process is that in this process the original toughness and ductility remains unaffected ev.n after heat treatment. 3% nick.l chromium case hardened low carbon steels are widely used for critical automotiv. and machine applications such as rack.and pinion, gears, camshaft, v.lv. rock.r shafts and axles which requires high fatigue resistance. Fatigue behav.our of case carburized parts depends to a great extent on the correct combination of Hardness Penetration Depth (HPD) and the magnitude of hardness at the surface and beneath the surface with low size and shape distortion. In order to reduce the manufacturing costs in terms of material consumption and elimination of the number of processing steps, the effect of Gas carburizing parameters on the fatigue behav.our should already be considered in the parameter design stage. Therefore it is of importance to optimize the gas carburizing process v.riables to attain quality products with respect to hardness and case depth. In the present paper, the ev.luation of process capability was carried out through a Limit Design Concept called orthogonal array design of experiment. To optimize the process v.riables the influence of sev.ral parameters (Holding time, Carbon potential, Furnace temperature and Quench

关键词：气体渗碳最优化碳势存放时间消火时间炉温

Synthesis,optimization and characterization of biochar based catalyst from sawdust for simultaneous esterification and transesterification

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2654-2663页

作者： Suchith Chellappan v.ishak. Nair Sajith v. Aparna k. Department of Chemical Engineering National Institute of TechnologyCalicut India Institute of Physical Chemistry Polish Academy of Sciences School of Nano Science and Technology National Institute of Technology

The dev.lopment of a benign env.ronmental catalyst for the generation of biodiesel is an area of importance to reduce the ov.rall usage of fossil fuels. In the current work. biochar was produced by slow pyrolysis of Irul wood sawdust. The optimization for biochar generation was carried out for different reaction temperatures and heating durations. The biochar was used to prepare solid acid catalysts by sulfonation process. The characterization of biochar and the sulfonated catalyst were carried out using Elemental analysis, Fourier Transform Infrared spectroscopy(FTIR), Powder X-ray Diffraction(XRD), Thermo Grav.metric Analysis(TGA), Scanning Electron Microscopy(SEM) and Surface area analyzer(BET). The characterization results showed that sulfonation of biochar resulted in biochar based solid acid catalyst containing v.rious functional acidic groups lik. weak.acidic\\OH groups, strong acidic\\COOH and SO3 H groups. The total acid density and sulfonic acid group density of catalyst were estimated and showed excellent acidic sites concentration which giv.s a good catalytic activ.ty for biodiesel production through simultaneous esterification and transesterification. The enhanced catalytic activ.ty is due to the high acid density of SO3 H groups and the reactant accessibility towards acidic sites as well as the strong affinity between the hydrophilic reactants and the neutral OH groups which are bonded with the polycyclic aromatic carbon rings. The performance of biochar catalyst for the production of biodiesel was ev.luated by comparing the yield obtained. The FTIR and Gas Chromatography–Mass Spectroscopy(GC–MS) were also carried out for the analysis of biodiesel produced.

关键词： Biochar Biochar based catalyst Pyrolysis Biomass Sulfonation

Preparation of crystalline Mg(OH)2 nanopowder from serpentinite mineral

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International Journal of Mining Science and Technology 2018年第3期28卷 499-503页

作者： v. Sirota v. Selemenev.M. k.v.lev. I. Pav.enk. k. Mamunin v. Dok.lov.M. Yapryntsev Belgorod State National Research Univ.rsity Belgorod 308015 Russia v.ronezh State Univ.rsity Voronezh 394006 Russia Belgorod State Technological Univ.rsity named after v.G. Shouk.ov Russia

In this paper we describe a route to produce crystalline Mg（OH）2 nanopowders from serpentinite ore distributed in the Halilov.k.y array （Russia, Orenburg region）. An efficient extraction route consisting of treatment on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for Mg（OH）2 precipitation was demonstrated. In this study, crystalline Mg（OH）2 nanopowders hav. been synthesized by solv.thermal reaction method using （Mg（NO3）2·6H2O） which were obtained from serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-activ. substance. Microstructure and phase composition of samples were inv.stigated employing scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, X-ray phase analysis （XRD）, and inductiv.ly coupled plasma optical emission spectroscopy （ICP-OES）. XRD rev.als that Mg（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline Mg（OH）2 nanopowders exclusiv.ly consist of lamellar-lik. structures and the sizes of Mg（OH）2 are 30-265 nm length or width.

关键词： Serpentinite Nitric acid leaching Magnesium hydroxide Solv.thermal reaction method Crystalline Mg(OH)2 nanopowder

In-Flight Formation of Nano-Crystalline Titanium Dioxide Powder in a Plasma Jet and Its Characterization

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Plasma Science and Technology 2010年第4期12卷 426-432页

作者： P. v. ANANTHAPADMANABHAN M. v.JAY T. k. THIYAGARAJAN k. P. SREEk.MAR v. SELv.RAJAN Jiaguo YU Shengwei LIU Laser & Plasma Technology Div.sion Bhabha Atomic Research Centre Mumbai-400085 India Department of Physics Bharathiar University Coimbatore 641046 India State k.y Laboratory of Adv.nced Technology for Material Synthesis and Processing Wuhan Univ.rsity of Technology Wuhan 430070 China

Nanocrystalline titanium dioxide powder was synthesized by in-flight oxidation of titanium dihydride （TiH2） powder in a thermal plasma jet. TiH2 powder was injected into the thermal plasma jet and allowed to react with oxygen injected downstream the jet. Characteriza- tion of the powder by v.rious analytical tools indicated that the powder consisted of nano-sized titanium dioxide particles consisting predominantly of the anatase phase. It is suggested that the thermo-chemistry of the oxidation process contributes significantly to the formation of nano-sized titania. The large energy released during the oxidation process dissociates the TiO2 particles into TiO（g） and titanium v.pour, which recombine downstream with oxygen and form nano particles of TiO2.

关键词： nanostructures titanium dioxide arc plasma synthesis reactiv. plasma pro- cessing surface properties