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Optimization of Performance and Emission Characteristics of PPCCI Engine fuelled with Ethanol and Diesel blends Using Grey-Taguchi Method

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Journal of Thermal Science 2018年第1期27卷 89-94页

作者： S.natarajan K.Pitchandi n.v.Mahalakshmi Department of Mechanical Engineering Sri Venkateswara College of EngineeringSriperumbudur-602117TamilnaduIndia. Department of Mechanical Engineering Sri Venkatcswara College of EngineeringSriperumbudur-602117TamilnaduIndia. Internal combustion Engineering Division Department of Mechanical EngineeringCollege of EngineeringAnna UniversityChennai-600025TamilnaduIndia.

The performance and emission characteristics of a PPCCI engine fuelled with ethanol and diesel blends were car- ded out on a single cylinder air cooled CI engine. In order to achieve the optimal process response with a limited number of experimental cycles, multi objective grey relational analysis had been applied for solving a multiple response optimization problem. Using grey relational grade and signal-to-noise ratio as a performance index, a combination of input parameters was prefigured so as to achieve optimum response characteristics. It was observed that 20% premixed ratio of blend was most suitable for use in a PPCCI engine without significantly affecting the engine performance and emissions characteristics.

关键词： PPCCI Biodiesel Optimization Grey-Taguchi method

Effect of multiaxial deformation on structure, mechanical properties, and corrosion resistance of a Mg-Ca alloy

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Journal of Magnesium and Alloys 2022年第1期10卷 284-298页

作者： n.Yu.Yurchenko n.D.Stepanov G.A.Salishchev v.n.Serebryany n.S.Martynenko E.A.Lukyanova L.L.Rokhlin n.Birbilis S.v.Dobatkin Y.Z.Estrin Belgorod State national Research University BelgorodRussia Federal State Budget Institution of Science A.A.Baikov Institute of Metallurgy and Materials Science.Russian Academy of SciencesMoscowRussia national University of Science and Technology"MISiS" MoscoicRussia Department of Materials Engineering Monash UniversityClaytonVIC 3800Australia Department of Mechanical Engineering The University of Western AustraliaMedian ds WA 6009、Australia

This article provides a report on the effect of multiaxial deformation(MAD) on the structure, texture, mechanical characteristics, and corrosion resistance of the Mg-0.8(wt.)% Ca alloy. MAD was carried out on the alloy in the as-cast and the annealed states in multiple passes, with a stepwise decrease in the deformation temperature from 450 to 250 ℃ in 50 ℃ steps. The cumulative true strain at the end of the process was 22.5. In the case of the as-cast alloy, this resulted in a refined microstructure characterized by an average grain size of 2.7 μm and a fraction of high-angle boundaries(HABs) of 57.6%. The corresponding values for the annealed alloy were 2.1 μm and 68.2%. The predominant mechanism of structure formation was associated with discontinuous and continuous dynamic recrystallization acting in concert. MAD was also shown to lead to the formation of a rather sharp prismatic texture in the as-cast alloy, whilst in the case of the annealed one the texture was weakened. A displacement of the basal poles {00.4} from the periphery to the center of a pole figure was observed. These changes in the microstructure and texture gave rise to a significant improvement of the mechanical characteristics of the alloy. This included an increase of the ultimate tensile strength reaching 308 MPa for annealed material and 264 MPa for the as-cast one in conjunction with a twofold increase in ductility. A further important result of the MAD processing was a reduction of the rate of electrochemical corrosion, as indicated by a significant decrease in the corrosion current density in both microstructural states of the alloy studied.

关键词： Metals and alloys Multiaxial deformation Microstructure Recrystallization Mechanical properties Corrosion

Structural Peculiarities and Magnetic Properties of nanoscale Terbium in Tb/Ti and Tb/Si Multilayers

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Chinese Physics Letters 2006年第1期23卷 196-199页

作者： A. v. Svalov v. O. vas'kovskiy G. v. Kurlyandskaya J. M. Barandiaran I. Orue n. n. Schegoleva A. n. Sorokin Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Universidad del Pals vasco UPv-EHU Facultad de Ciencias Depto Electricidad y ElectrOnica Apdo. 644 48080 Bilbao Spain Institute of Metal Physics Ural Branch of RAS Kovalevskaya str. 18 620219 Ekaterinburg Russia

The structure and the magnetic properties of rf-sputtered nauoscale Tb in [Tb/Ti]n and [Tb/Si] multilayers have been studied experimentally. It is found that the structure of Tb layers changes, transforming from a fine-crystalline state of Tb into an amorphous state as the magnetic layer thickness decreases. The observed displacement of a magnetic ordering temperature to the lower temperature range and the shift of magnetic hysteresis obtained in the ZFC-FC terms may be caused by the size effect and the amorphization. Both the first and the second suppress the exchange interaction and decrease the crystalline magnetic anisotropy. The type of material of nonmagnetic spacers between the Tb layers plays a certain role in these changes.

关键词： FERROMAGnETIC-RESOnAnCE FILMS TEMPERATURE DEPEnDEnCE THICKnESS LAYERS

Protozoan colonization on artificial substrates in relation to water quality in a tropical Indian harbour

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Journal of Environmental Sciences 2001年第2期13卷 143-147页

作者： v.R.Bharati R.n.Khan C.Kalavati A.v.Raman Department of Zoology Andhra UniversityVisakhapatnam 530003India.

A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma, and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, vorticella, Lagynophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi disc transparency(0.48m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 ℃. Here, the nanoflagellates( spumella ) colonized first, followed by microcilliate( Tetrahymena ) and sessile form( vorticella ). Station B, located on the seaward side, was characterized by relatively less stressed environmental conditions with transparency 1.85m and dissolved oxygen value of 6 04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 ℃ were recorded at “B'. At this station, the nanoflagellate Polytoma was first documented to colonize on the substrates, followed by microcilliate( Lagynophrya ) and suctorid( Heliophyra ). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities.

关键词： Protozoan colonization on artificial substrates in relation to water quality in a tropical Indian harbour

Biomass Industrial Effluent Effect on Carbohydrates,Aminoacids,nitrite and nitrite Enzyme Activities of Arachis hypogaea L.

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Agricultural Sciences in China 2009年第2期8卷 203-215页

作者： P C nagajyoti n Dinakar S Suresh Y Udaykiran C Suresh T n v K v Prasad T Damodharam Department of Environmental Sciences Sri Venkateswara University national Institute of nutrition Hyderabad Regional Agricultural Research Station N.G. Ranga Agriculture University

The objectives of the present investigations are to see the effects of biomass power plant effluent on the carbohydrates, aminoacids, nitrite and nitrite enzyme activitiesand proline of Arachis hypogaea L. var TCGS 320 under controlled pot culture methods. Plants were cultivated with 25, 50, 75 and 100% of the effluent and a control without the effluent. The treatment of the crop with 25% of the effluent has shown stimulatory effect on all the biochemical parameters studied. Carbohydrates, starch, aminoacids, protein, nitrate and nitrite reductase enzymatic activities have increased in 10, 15, 20 DAS （days after sowing）. In 25 and 30 DAS all biochemical parameters have decreased, due to environmental factors （rainfall, temperature, humidity, etc.）. The present investigation clearly indicated that the biomass power plant effluent has stimulatory effect on all the biochemical contents at lower concentration, and at higher concentration they have deleterious effects.

关键词： biomass power plant effluent biochemical parameters Arachis hypogaea stimulatory effect

La^(3+) -doped SrBi_2Ta_2O_9 thin films for FRAM synthesized by sol-gel method

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Journal of Rare Earths 2014年第3期32卷 277-281页

作者： v.v.Sidsky A.v.Semchenko A.G.Rybakov v.v.Kolos A.S.Turtsevich A.n.Asadchyi W.Strek F.Skorina Gomel State University JSC ?InTEGRAL? 121A Kazintsa st. Minsk 220108 Belarus Institute of Low Temperature and Structures Research PAn Okolna st.2 Wroclaw Poland

This paper discusses the possibility of synthesis of SBTL sol-gel films for use as active layers for non-volatile memory （FRAM）. La-doped SrBi2Ta209 thin films were synthesized by sol-gel method on Pt/TiO2/BPSG/SiO2/Si substrates. The structural features of the surface （AFM）, crystallization behavior （XRD） during the heating and ferroelectric properties of synthesized films were discussed. It was shown that an optimum surface structure and a high share of perovskite phase of SBTL-films were compared to SBT-films （Theating=800 ℃）. Achieved ferroelectric parameters suggested the possibility of using synthesized SBTL sol-gel films in non-volatile memory devices.

关键词： ferroelectric thin films sol-gel method lanthanum ion non-volatile memory rare earths

Dibaryon resonances and short-range nn interaction

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Chinese Physics C 2022年第11期46卷 238-261页

作者： v.I.Kukulin v.n.Pomerantsev O.A.Rubtsova M.n.Platonova I.T.Obukhovsky Skobeltsyn Institute of nuclear Physics Lomonosov Moscow State UniversityLeninskie Gory 1/2119991 MoscowRussia

The dibaryon concept for nuclear force is presented,assuming that the attraction between nucleons at medium distances is mainly due to the s-channel exchange of an intermediate six-quark(dibaryon)*** construct the respective nn interaction model,a microscopic six-quark description of the nn system is used,in which symmetry aspects play a special *** is shown that the nn interaction in all important partial waves can be described by the superposition of long-range t-channel one-pion exchange and s-channel exchange by an intermediate *** model developed in this study provides a good description of both elastic phase shifts and inelasticities of nn scattering in all S,P,D,and F partial waves at energies from zero to 600-800 Mev and even *** parameters of the intermediate six-quark states,corresponding to the best fit of nn scattering data,are found to be consistent with the parameters of the known dibaryon resonances in those nn partial configurations,where their existence has been experimentally *** for new dibaryon states are given as well.

关键词： nucleon-nucleon interaction dibaryon resonances short-range nuclear force

Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

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Plasma Science and Technology 2024年第9期26卷 32-39页

作者： victor F TARASEnKO Dmitry v BELOPLOTOv Alexei n PAnCHEnKO Dmitry A SOROKIn Institute of High Current Electronics Siberian BranchRussian Academy of SciencesTomsk 634055Russia national Research Tomsk State University Tomsk 634050Russia

The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark *** and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were ***-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)*** minimum delay between the camera channels could be as short as≈0.1 *** made it possible to study the gap breakdown process with subnanosecond *** was observed that a wide-diameter streamer develops from the high-voltage pointed *** ionization processes near the grounded pin electrode started when the streamer crossed half of the *** bridging the gap by the streamer,a diffuse discharge was *** development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next *** was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter *** thin luminous tracks were observed against the background of a discharge plasma *** has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

关键词： needle electrodes short voltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles

Low-Frequency Hydroacoustic Experiments on the Shelf Using the Data of Geoacoustic Sediment Model

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Chinese Physics Letters 2014年第12期31卷 66-69页

作者： SAMCHEnKO A. n. KOSHELEvA A.v. SHvYREv A. n. PIvOvAROv A. A. Il'icheve's Pacific Oceanological Institute (POI) FEB RAS Vladivostok 690041 Russia

Acoustic and seismoacoustic methods have become the most perspective and intensely developed meth- ods in the research of dynamic processes and inho- mogeneities in shallow water. Seismoacoustic moni- toring allows one to draw conclusions about the pres- ence of different inhomogeneities in the water environ- ment and to identify various dynamic processes in the oceanic shelf zone. Studies of the propagation of hy- droacoustic signals of different frequencies and config- urations are widely discussed in scientific publications in Russia, China and the United States Solutions to inversion problems in acoustics, the con- struction of geoacoustic models and research of low- frequency acoustic signals with respect to the absorb- ing bottom are without any doubt at the forefront of underwater acoustics.

关键词： UnDERWATER acoustics SEDIMEnTS (Geology) ACOUSTIC signal processing WATER COnTInEnTAL shelf MATHEMATICAL models