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Com.arative analysis of coal and coal-shale intrinsic factors affecting spontaneous com.ustion

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International Journal of Coal Science & Technology 2018年第3期5卷 282-294页

作者： m. Onifade b. Genc The School of m.ning Engineering University of the Witwatersrand P.O. WITS Johannesburg 2050 South Africa

Coal and coal-shales tend to undergo spontaneous com.ustion under favourable atm.spheric conditions. Spontaneous com.ustion liability index and intrinsic properties of coals and coal-shales varies between （above and below） coal seam.. The spontaneous com.ustion liability index （obtained from.the Wits-Ehac Index） and intrinsic properties （obtained from.proxim.te, ultim.te, and petrographic analysis） of fourteen sam.les representative of in situ coal （bitum.nous） and fourteen coal-shales obtained in Witbank coalfield, South Africa were experim.ntally studied. Com.arative analysis of the relationships between the spontaneous com.ustion liability index and intrinsic properties of coals and coalshales were established to evaluate their effects on self-heating potential. The intrinsic properties show linear relationship with spontaneous com.ustion liability and therefore, identifies the factors affecting spontaneous com.ustion of these m.terials. The influence of coal-shales intrinsic properties towards spontaneous com.ustion liability shows higher correlation coefficients than the coals. both coals and coal-shales show inertinite m.ceral as m.jor constituents than the vitrinite and liptinite m.cerals, hence the reactivity of inertinite m.cerals m.y show greater influence on spontaneous com.ustion liability. A definite positive or negative trends exists between the intrinsic properties and spontaneous com.ustion liability index. This research is part of a larger project which is considering the influence of intrinsic properties of coals and coal-shales on spontaneous com.ustion liability.

关键词： Coal-shales Spontaneous com.ustion Liability index Statistical analysis and correlation coefficient

Effects of calcination tem.erature and tim. on the Ca3Co4O9 purity when synthesized using starch-assisted sol-gel com.ustion m.thod

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Journal of Advanced Ceram.cs 2020年第2期9卷 162-172页

作者： m.A.m.HAm.ED m.b.UDAY S.IZm.N School of m.chanical Engineering Faculty of EngineeringUniversiti Teknologi Malaysia(UTM)UTM Skudai 81310JohorMalaysia Centre for Advanced Com.osite m.terials(CACm. Institute for Vehicle Systems and EngineeringUniversiti Teknologi MalaysiaUTM Skudai 81310JohorMalaysia Departm.nt of m.terials Engineering College of EngineeringUniversity of BasrahBasrahIraq

Ca3Co4O9 is a p-type sem.conducting m.terial that is well-known for its therm.electric(TE),m.gnetic,electronic,and electro-optic *** this study,sol–gel autoignition was used to prepare Ca3Co4O9 at different calcination tem.eratures(773,873,973,and 1073 K)and tim.(4,6,8,10,12,and 14 h)using starch as a *** phase and m.crostructure of the prepared Ca3Co4O9 powder were ***–differential therm.l analysis(TGA)confirm. that the final weight loss occurred at 1073 K to form.Ca3Co4O9 stable *** variable-pressure scanning electron m.croscopy(VP-SEm.im.ges show that the size of powder particles increases from.1.15 to 1.47μm.as calcination tim. increases from.4 to 12 h,and the size rem.ins alm.st constant thereafter.A sim.lar pattern is also observed on the increm.nt of the crystallite size and percentage of crystallinity with X-ray diffraction(XRD)*** highest crystallinity is found about 92.9%when the powder was calcinated at 1073 K for 12 and 14 h with 458 and 460Åcrystallite size,*** dispersive X-ray spectroscopy(EDS)analysis dem.nstrates that the calcinated powder has a high intensity of Ca,Co,and O with uniform.***-resolution transm.ssion electron m.croscopy(HRTEm.im.ges prove that there is no distinct lattice distortion defect on the crystal structure.

关键词： calcium.cobalt oxide sol-gel starch com.ustion m.thod crystallite size crystallinity

Perform.nce, em.ssion and com.ustion characteristics of CI engine fuelled with diesel and hydrogen

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Frontiers in Energy 2015年第4期9卷 486-494页

作者： R. Senthil KUm.R m. LOGANATHAN E. james GUNASEKARAN Departm.nt of m.chanical Engineering Annamalai University Chi- dambaram 608002 India

Hydrogen （H2） is being considered as a prim.ry autom.tive fuel and as a replacem.nt for conventional fuels. Som. of the desirable properties, like high flam. velocity, high calorific value m.tivate us to use hydrogen fuel as a dual fuel m.de in diesel engine. In this experim.nt, hydrogen was inducted in the inlet m.nifold with intake air. The experim.nts were conducted on a four stroke, single cylinder, water cooled, direct injection （DI）, diesel engine at a speed of 1500r/m.n. Hydrogen was stored in a high pressure cylinder and supplied to the inlet m.nifold through a water-and-air-based flam. arrestor. A pressure regulator was used to reduce the cylinder pressure from.140 bar to 2 bar. The hydrogen was inducted with a volum. flow rate of 41 pm. 61 pm.and 81 pm. respectively by a digital volum. flow m.ter. The engine perform.nce, em.ssion and com.ustion param.ters were analyzed at various flow rates of hydrogen and com.ared with diesel fuel operation. The brake therm.l efficiency （bTE） was increased and brake specific fuel consum.tion （bSFC） decreased for the hydrogen flow rate of 81 pm.as com.ared to the diesel and lower volum. flow rates of hydrogen. The hydrocarbon （HC） and carbon m.noxide （CO） were decreased and the oxides of nitrogen （NOx） increased for higher volum. flow rates of hydrogen com.ared to diesel and lower volum. flow rates of hydrogen. The heat release rate and cylinder pressure was increased for higher volum. flow rates of hydrogen com.ared to diesel and lower volum. flow rates of hydrogen.

关键词： hydrogen brake therm.l efficiency crankangle com.ressed ignition (CI)

Cosm.logical Expansion and Its Effect on Sm.ll System.

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Com.unications in Theoretical Physics 2006年第6X期46卷 987-990页

作者： b. m.rza m. Zam.ni-Nasab Departm.nt of Physics Isfahan University of Technology (IUT) Isfahan (84156) Iran

In order to study the effect of large scale cosm.logical expansion on sm.ll system., we assum. a Friedm.nn- Robertson-Walker type coordinate system.in presence of a nonzero cosm.logical constant and derive a non-static Reissner-Nrdstr6m.m.tric. It is an analytic function of r for all values except at r = O, which is singular. by determ.ning the equation of m.tion in this m.tric we can estim.te how expansion of the universe m.y affect Pioneer＇s m.tion. because the m.tric does not have any event horizon and so high potential regions are accessible, this m.y help us in better understanding AGN phenom.non.

关键词： general relativity exact solution

Ham.er-Im.act SH-Wave Seism.c Reflection m.thods in Neotectonic Investigations: General Observations and Case Histories from.the m.ssissippi Em.aym.nt, U.S.A.

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Journal of China University of Geosciences 2009年第3期20卷 513-525页

作者： james b Harris m.llsaps College Jackson MississippiUSA

Shallow shear-wave seism.c reflection im.ging, using a sledgeham.er and m.ss energy source and standard processing, has becom. increasingly com.on in m.pping near-surface geologic features, especially in water-saturated, unconsolidated sedim.nts. Tests of the m.thod in the m.ssissippi Em.aym.nt region of the central United States show interpretable reflection arrivals in the depth range of 〈10 m.to 〉100 m.with the potential for increased resolution when com.ared with com.ressional-wave data. Shear-wave reflection prof＇des were used to help interpret the significance of neotectonic surface deform.tion at five sites in the m.ssissippi Em.aym.nt. The interpreted profiles show a range of shallow structural styles that include reverse faulting, fault propagation folding, and reactivated norm.l faulting, and provide crucial subsurface evidence in support of paleoseism.logic trenching and shallow drilling.

关键词： shear wave seism.c reflection neotectonics.

Perform.nce evaluation of up-flow anaerobic sludge blanket(UASb) reactor for treatm.nt of paper m.ll wastewater

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Journal of Environm.ntal Sciences 2004年第2期16卷 194-198页

作者： m. m.hadevaswam. b.m. Sadashiva m.rthy A.R. Girijam.a Departm.nt of Environm.ntal Engineering S.J.College of EngineeringDepartment of Environmental EngineeringS.J.College of EngineeringDepartment of Environmental EngineeringS.J.College of Engineering Mysore-570 006Karnataka StateIndiaMysore-570 006Karnataka StateIndiaMysore-570 006Karnataka StateIndia

The present study deals with the perform.nce evaluation of the UASb reactor under varied organic loading rate(OLR) for the treatm.nt of paper m.ll wastewater. The sludge granulation process started after 120 days from.the start-up period. Sludge granules size was found to be 0 8 m. at OLR of 1 72 kgCOD/(m. 3·d), which reached m.xim.m.size of about 1 0 to 1 2 m. at OLR of 2 1 kgCOD/(m. 3·d). At the end of initial OLR of 1 0 kgCOD/(m. 3·d) the VSS concentration was 12 86 gVSS/L, which got increased to 38 05 gVSS/L at the end of an OLR 2 1 kgCOD/(m. 3·d). m.st of the tim.s VFA recorded were well within the lim.t of VFA reported in anaerobic ferm.ntation process. m.ny tim.s the pH observed was between 6 5 and 7 8, which is m.re favorable for any anaerobic process. It is also found that pH within the reactor increases along with the height of reactor. The total m.xim.m.biogas production was found to be 0 40 L/gCOD rem.vals at OLR of 2 1 kgCOD/(m. 3·d) and the m.xim.m.bOD rem.val at this stage was observed to be 90%.

关键词： UASb biogas anaerobic digestion sludge loading rate organic loading rate

Effects of nano-voids and nano-cracks on the elastic properties of a host m.dium. xfem.m.deling with level-set function and free surface energy

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Acta m.chanica Sinica 2019年第4期35卷 799-811页

作者： b.E. Hachi D. Hachi m. Haboussi Laboratoire de Développem.nt en m.canique et m.tériaux (LDm.) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire d’Autom.tique Appliquée et Diagnostics Industriels (LAADI) Université de Djelfa PB 3117 Djelfa Algérie Laboratoire des Sciences des Procédés et des m.tériaux (LSPm. Université Paris 13 UPR 3407 CNRS Paris France

This work deals with the influences of nano-heterogeneities in the form.of voids/cavities or cracks on the elastic (please confirm.which word is correct. effective or elastic? According to the title of paper, I choose elastic.) properties of a host m.dium. With a relatively large ratio of apparent-surface to volum. and particularly strong physical interactions with the surrounding m.dium.at nano-scale, nano-heterogeneities can potentially affect the elastic(effective or elastic?) properties of the parent m.dium.(m.trix) containing them.in a significant m.nner. This has been reported by various theoretical and experim.ntal studies, som. of them.are discussed in the present paper. To describe the positive (reinforcem.nt) or negative (degradation) effect of the nano-heterogeneities from.the m.deling perspective, it is necessary to take into account the energy of interfaces/surfaces between nano-heterogeneities and the m.trix which, by the fact of the relatively large extent of their apparent surface and their strong physical interaction with their neighborhood, can no longer be neglected com.ared to those of the volum. energy. Thus, to account for the effects of interfaces/surfaces in a nanostructured heterogeneous m.dium. the coherent interface m.del is considered in the present investigation within a periodic hom.genization procedure. In this interface/surface m.del, the displacem.nt vector is assum.d to be continuous across the interface while the stress vector is considered to be discontinuous and satisfying the Laplace-Young equations. To solve these equations coupled to the classical m.chanical equilibrium.problem. a num.rical sim.lation tool is developed in a two-dim.nsional (2D) context using the eXtended Finite Elem.nt m.thod (XFEm. and the Level-Set functions. The developed num.rical tool is then used to carry out a detailed analysis about the effect of nano-heterogeneities on the overall m.chanical properties of a m.dium. The nano-heterogeneities are present

关键词： Interface/Surface energy XFEm Level-Set function Periodic hom.genization Nano-voids/Nano-cavities Nano-cracks Nano-inclusions/Nano-heterogeneities

Synthesis, spectroscopic characterization, and therm.l decom.osition kinetics of som. lanthanide(III) nitrate com.lexes of 2-(N-o-hydroxyacetophenone) am.no-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

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Journal of Rare Earths 2008年第4期26卷 463-468页

作者： K. m.hanan m. Thankam.ny b. Sindhu Kum.ri Departm.nt of Chem.stry University of Kerala Kariavattom Campus Trivandrum-695 581. Kerala India

Com.lexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm.Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb（Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）am.no-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene （HAAT） form.d by the condensation of o-hydroxyacetophenone and 2-am.no-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene were synthesized and characterized on the basis of elem.ntal analyses, m.lar conductance m.asurem.nts, m.gnetic susceptibility data, UV-Visible, IR, and Nm. spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the m.tal ion through ONO donor sequence. A coordination num.er nine was proposed for the com.lexes. Therm.l decom.osition studies of the ligand and lanthanum.Ⅲ） com.lex were carried out and kinetic param.ters were calculated using Coats-Redfem.equation. The decom.osition reactions followed random.nucleation m.chanism.with one nucleus on each particle.

关键词： lanthanides o-hydroxyacetophenone m.lar conductance m.gnetic susceptibility therm.l study rare earths

Hot-nanoparticle-m.diated fusion of selected cells

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Nano Research 2017年第6期10卷 2034-2045页

作者： Azra bahadori Lene b. Oddershede Poul m. bendix blegdam.vej 17 Niels Bohr Institute University of Copenhagen 2100 Copenhagen Denmark Lundbeck Foundation Center for biom.m.ranes in Nanom.dicine University of Copenhagen 2100 Copenhagen Denmark

Com.lete fusion of two selected ceils allows for the creation of novel hybrid cells with inherited genetic properties from.both original cells. Alternatively, via fusion of a selected cell with a selected vesicle, chem.cals or genes can be directly delivered into the cell of interest, to control cellular reactions or gene expression. Here, we dem.nstrate how to perform.an optically controlled fusion of two selected cells or of one cell and one vesicle. Fusion is m.diated by laser irradiating plasm.nic gold nanoparticles optically trapped between two cells （or a vesicle and a cell） of interest. This hot-particle-m.diated fusion causes total m.xing of the two cytoplasm. and the two cell m.m.ranes resulting in form.tion of a new hybrid cell with an intact cell m.m.rane and enzym.tic activity following fusion. Sim.larly, fusion between a vesicle and a cell results in delivery of the vesicle cargo to the cytoplasm. and after fusion, the cell shows signs of viability. The m.thod is an im.lem.ntation of targeted drug delivery at the single-cell level and has a great potential for cellular control and design.

关键词： cell fusion m.m.rane fusion gold nanoparticle plasm.nic heating optical trapping