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Contrasting plant growth performance of invasive polyploid and native diploid Prosopis is mediated by the soil bacterial community

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Ecological Processes 2023年第1期12卷 193-203页

作者： rishabh Kaushik Meesha Sharma Ch.v.ramana Ch.Sasikala Maharaj K.Pandit Jealott’s Hill International research Centre WarfieldBracknell RG426EYEnglandUK Department of Environmental Studies University of DelhiDelhi 110007India Department of Plant Sciences School of Life SciencesUniversity of HyderabadP.O.Central UniversityHyderabad 500046India Bacterial Discovery Laboratory Centre for EnvironmentInstitute of Science and TechnologyJ.N.T.University HyderabadKukatpallyHyderabad 500085India Jindal School of Environment&Sustainability OP Jindal Global UniversitySonipatHaryana 131001India

Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth *** studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been ***,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis *** Plant growth performance of invasive *** was significantly reduced when grown in sterilized soils,whereas native *** showed enhanced growth performance in the sterilized *** grown in the soil inoculated with the specific Streptomyces isolate from ***(PJ1),the growth performance of invasive *** was significantly enhanced while that of native *** seedlings was significantly ***,inoculation of *** and *** seedlings with Streptomyces isolate from the rhizosphere of native ***(PC1)had no significant effect on the growth performances either of *** or *** Our study reveals that invasive *** experiences positive feedback from the non-native soil bacterial community,while the native *** experiences negative feedback from its soil bacterial *** results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.

关键词： Soil bacteria Streptomyces Invasive Prosopis juliflora Prosopis cineraria Soil microbiota

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Microstructure and mechanical properties of similar and dissimilar metal gas tungsten constricted arc welds:Maraging steel to 13-8 Mo stainless steel

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Defence Technology（防务技术） 2019年第1期15卷 111-121页

作者： C.v.S.murthy A.Gopala Krishna G.M.reddy Defence research and Development Laboratory Jawaharlal Nehru Technological University Defence Metallurgical research Laboratory

Maraging steel (250) and 13-8 Mo stainless steel plates were joined by gas tungsten constricted arc welding(GTCAW) process in similar and dissimilar metal combinations using 13-8 Mo stainless steel filler wire. The similar and dissimilar metal welds made in solutionized condition were subjected to standard post weld hardening treatments direct ageing at 485 ℃, soaking for 31/2 hours followed by air cooling(ageing treatment of maraging steel) and direct ageing at 510 ℃, soaking for 4 h followed by air cooling(ageing treatment of 13-8 Mo stainless steel). The joint characterization studies include microstructure examination, microhardness survey across the weldments and transverse weld tensile *** and dissimilar metal weldments responded to both the post weld ageing treatment. After post weld aging, increase in yield strength, UTS and slight reduction in % elongation of similar and dissimilar metal were observed. The observed tensile properties were correlated with microstructure and hardness distribution across the welds.

关键词： Maraging steel(250) 13-8 Mo stainless steel Mechanical properties Microstructure

Effects of yttria content on the CMAS infiltration resistance of yttria stabilized thermal barrier coatings system

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Journal of Materials Science & Technology 2020年第8期36卷 74-83页

作者： Juan JGomez Chavez ravisankar Naraparaju Peter Mechnich Klemens Kelm Uwe Schulz C.v.ramana University of Texas at El Paso Department of Mechanical EngineeringEl PasoTX79968USA German Aerospace Center(DLr) Institute of Materials ResearchCologne51170Germany

The effects of YO(1.5)doping in yttria-zirconia based thermal barrier coatings(TBCs)against CMAS interaction/infiltration are *** TBCs with an YO(1.5)content ranging from 43–67 mol.%(balance Zr O2)were produced by electron beam physical vapor deposition(EB-PvD)*** results reveal a trend of higher apatite formation probability with the higher free YO(1.5)available in the yttriazirconia ***,the infiltration resistance and amount of consumed coating appears to be strongly dependent on the YO(1.5)content in the *** thinnest reaction layer and lowest infiltration was found for the highest produced 67 YO(1.5)*** XrD experiments with volcanic ash/YO(1.5)powder mixtures with higher yttria contents than in the coatings(80 YO(1.5)and pure YO(1.5))also showed higher apatite formation with respect to increasing yttria *** threshold composition to promote apatite-based reaction products was found to be around 50 YO(1.5)in zirconia which was proved in the coatings and XrD powder *** YO(1.5)-ZrO2-Fe O-TiO2 bearing zirconolite-type phase was formed as a reaction product for all the coating compositions which implicates that TiO2 in the melt acts as a trigger for zirconolite *** phase could be detrimental for CMAS/volcanic ash infiltration resistance since it can be formed alongside with apatite which controls or limits the amount of Y^(3+)available for glass *** Fe rich garnet phase containing all the possible elements exhibited a slower nucleation compared to apatite and its growth was enhanced with slow cooling *** implications of phase stability and heat treatment effects on the reaction products are discussed for tests performed at 1250°C.

关键词： CMAS volcanic ash Infiltration Electron beam physical vapor deposition Thermal barrier coating

Mechanical and thermal properties of AA7075/TiO2/Fly ash hybrid composites obtained by hot forging

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Progress in Natural Science:Materials International 2017年第4期27卷 474-481页

作者： K.v.Shivananda murthy D.P.Girish r.Keshavamurthy Temel varol Praveennath G.Koppad Department of Mechanical Engineering Government Engineering Colleg 2. Department of Mechanical Engineering Dayananda Sagar College of Engineering 3. Department of Metallurgical and Materials Engineering Karadeniz Technical University 4. Department of Mechanical Engineering CMR Institute of Technology

In the present paper, multiple reinforcements TiO2 and fly ash were utilized for the fabrication of AA7075 matrix based hybrid composites using stir casting technique followed by hot forging. In hybrid composites, the fly ash content was fixed to 3 wt% while that of TiO2 was varied from 2.5 to 10 wt%. Scanning electron microscopy images revealed homogenous dispersion of both the reinforcements in AA7075 *** test was conducted to study the mechanical behaviour of hybrid composites. The hybrid composites showed increase in compressive strength with the incorporation of multiple reinforcements and further increased with the increase in the weight fractions of TiO2 particles. The coefficient of thermal expansion was measured between 50 and 250 ℃ with a high precision thermal mechanical analyser. The thermal coefficient of hybrid composites decreased with the addition of TiO2 and fly ash. However a slight decrease in thermal conductivity of hybrid composites was observed when compared to that of AA7075 alloy.

关键词： Hybrid composites Hot forging Mechanical properties Thermal properties

Development of Heat Transfer Coefficient and Friction Factor Correlations for Serrated Fins in Water Medium using CFD

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Journal of Physical Science and Application 2015年第3期5卷 238-248页

作者： K v ramana murthy C ranganayakulu T P Ashok Babu General systems Directorate Aeronautical Development Agency Bangalore -560017 India Mechanical Engineering Dept National Institute of Technology Surathkal -575025 India.

Abstract： The most popularly used fin types in compact heat exchangers are the serrated fins, wavy fins, louvered fins and plain fins. Amongst these fin types the serrated fins assume lot of importance due to its enhanced thermo-hydraulic performance. Thermo-hydraulic design of CHEs （Compact heat exchangers） is strongly dependent upon the predicted/measured dimensionless performance （Colburnj factor and Fanning friction vs. reynolds number） of heat transfer surfaces. This paper describes the numerical analysis to study the heat transfer coefficient and friction factor of Serrated fins in water medium. CFD （Computational fluid dynamics） methodology has been used to develop the single phase water heat transfer coefficient and friction factor correlations for serrated fins using ANSYS Fluent 14.5. The results are compared with previous air-cooled models and experimental results of water. The water cooled CFD analysis results shows that the Prandtl number has a large effect on the Nusselt number of the serrated fin geometry. Finally, the generalized correlations are developed for serrated fins taking all geometrical parameters into account. This numerical estimation can reduce the number of tests/experiments to a minimum for similar applications.

关键词： Compact heat exchanger serrated fins CFD (Computational fluid dynamics) analysis water medium thermo-hydraulicperformance colburnj factor friction factors

Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine for the reduction of NOx emissions

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Frontiers in Energy 2012年第3期6卷 304-310页

作者： K. vENKATESWArLU B. S. r. murthy v. v. SUBBArAO K. vijaya KUMAr Mechanical Engineering Department K.L University Guntur 522502India Mechanical Engineering Department Q.I.S College of Engineering and Technology Ongole 523272 India Mechanical Engineering Department J.N.T.U Kakinada Kakinada533033 India

Cetane improvers reduce the ignition delay, which in turn reduces the combustion temperatures thereby reduce NOx emissions. Exhaust gas recirculation （EGr） proved to be an effective way to reduce the NOx emissions. In this present experimental work, a combination of exhaust gas recirculation and cetane improver ethyl hexyl nitrate （EHN） is used to investigate the performance and exhaust emissions of a single cylinder four stroke naturally aspirated direct injection and air cooled diesel engine. Test results show that the brake thermal efficiency increases with the increase in the percentage of EGr which is accompanied by a reduction in brake specific fuel consumption and exhaust gas temperatures, and that bio- diesel with cetane improver under 20% EGr reduces NOx emissions by 33% when compared to baseline fuel without EGr. However carbon monoxide （CO）, hydro carbon （HC） and smoke emissions increase with an increase in percentage of EGr.

关键词： additive exhaust gas recirculation (EGr),emissions ethyl hexyl nitrate (EHN) performance

Coarse to Fine: The role of Severe Plastic Deformation in Advancing Titanium-Based Medical Implants - A Comprehensive review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana r Mihajlović Bojan I Međo Ivana Lj Cvijović-Alagić veljko r Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia vinča Institute of Nuclear Sci-ences-National Institute of the republic of Serbia University of Belgrade11001BeogradSerbia Innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Single-pulse ultrafast real-time simultaneous planar imaging of femtosecond laser-nanoparticle dynamics in flames

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Light(Science & Applications) 2024年第10期13卷 2312-2320页

作者： Yogeshwar Nath Mishra Peng Wang Florian J.Bauer murthy S.Gudipati Lihong v.Wang Caltech Optical Imaging Laboratory Andrew and Peggy Cheng Department of Medical EngineeringDepartment of Electrical EngineeringCalifornia Institute of Technology1200 East California BoulevardMail Code 138-78PasadenaCA 91125USA Science Division Jet Propulsion LaboratoryCalifornia Institute of Technology4800 Oak Grove DrivePasadenaCA 91109USA Lehrstuhl für Technische Thermodynamik(LTT)and Erlangen Graduate School in Advanced Optical Technologies(SAOT) Universität Erlangen-NürnbergErlangen 91058Germany

The creation of carbonaceous nanoparticles and their dynamics in hydrocarbon flames are still debated in environmental,combustion,and material *** this study,we introduce single-pulse femtosecond laser sheetcompressed ultrafast photography(fsLS-CUP),an ultrafast imaging technique specifically designed to shed light on and capture ultrafast dynamics stemming from interactions between femtosecond lasers and nanoparticles in flames in a ***-CUP enables the first-time real-time billion frames-per-second(Gfps)simultaneous twodimensional(2D)imaging of laser-induced fluorescence(LIF)and laser-induced heating(LIH)that are originated from polycyclic aromatic hydrocarbons(PAHs)and soot particles,***,fsLS-CUP provides the real-time spatiotemporal map of femtosecond laser-soot interaction as elastic light scattering(ELS)at an astonishing 250 *** contrast to existing single-shot ultrafast imaging approaches,which are limited to millions of frames per second only and require multiple laser pulses,our method employs only a single pulse and captures the entire dynamics of laserinduced signals at hundreds of *** a single pulse does not change the optical properties of nanoparticles for a following pulse,thus allowing reliable spatiotemporal ***,we found that particle inception and growth are derived from *** essence,as an imaging modality,fsLS-CUP offers ultrafast 2D diagnostics,contributing to the fundamental understanding of nanoparticle’s inception and broader applications across different fields,such as material science and biomedical engineering.

关键词： pulse scattering dynamics

Effect of wall temperature modulation on the heat transfer characteristics of droplet-train flow inside a rectangular microchannel

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Chinese Journal of Chemical Engineering 2020年第3期28卷 685-697页

作者： vivekanand S.v.B.,raju v.r.K. Department of Mechanical Engineering National Institute of TechnologyWarangalTelangana 506004India

The numerical studies of water–oil two-phase slug flow inside a two-dimensional vertical microchannel subjected to modulated wall temperature boundary conditions have been discussed in the present *** researchers have contributed their efforts in exploring the characteristics of Taylor flows inside microchannel under constant wall heat flux or isothermal wall ***,there is no study available in the literature which discusses the impact of modulated thermal wall boundary conditions on the heat transfer behavior of slug flows inside ***,to bridge this gap,an effort has been made to understand the heat transfer characteristics of the flow under sinusoidal wall temperature ***,a single phase flow and heat transfer study was performed in microchannels,and the results of the fully developed velocity profile and heat transfer rate were validated with benchmark analytical *** an optimal selection of the combination of sinusoidal thermal wall boundary conditions has been made for the two-phase slug flow ***,the effects of amplitude(0 bεb 0.03)and frequency(0 bωb 750πrad·s-1)of the sinusoidal wall temperature profile on the heat transfer have been studied using the optimal combination of the wall boundary *** results of the numerical study using modulated temperature conditions on channel walls showed a significant improvement in the heat transfer over liquid-only flow by approximately 50%as well as over two-phase flow without wall temperature *** non-dimensional temperature contours obtained for different cases of temperature modulation clearly explain the root cause of such improvement in the heat ***,the results based on the hydrodynamics of the flow have also been reported in terms of variation of droplet shapes and film *** influence of Capillary number on the film thickness as well as heat transfer rates has also been *** addition,the measured fil

关键词： Heat transfer Microchannel Modulation Surface tension Taylor flow