Ganga-Brahmaputra-Meghna(GBM)river basin is the third-largest and one of the most populated river basins in the world.As climate change is affecting most of the hydrometeorological variables across the globe,this stud...Ganga-Brahmaputra-Meghna(GBM)river basin is the third-largest and one of the most populated river basins in the world.As climate change is affecting most of the hydrometeorological variables across the globe,this study investigated the existence of climate change signal in all four climatological seasons in the GBM river basin and assessed the contribution of anthropogenic activities,i.e.,Greenhouse Gases(GHGs)emission in the change.Significant decreasing trends in the monsoon and a small increase in pre-monsoon precipitation were observed.Negligible change was detected in post-monsoon and winter season precipitation.CMIP5 GCMs were used for climate change detection,change point estimation,and attribution studies.Support Vector Machine(SVM)regression method was adopted to downscale GCM variables at the local scale.Monte-Carlo simulation approach was used to detect changes in different seasons.The climate change‘signals’were detectable after the year 1980 using Signal to Noise ratio(SNR)method in the majority of central and north-western regions.The change point was detectable only in annual monsoon precipitation at the basin level.Attribution analysis indicated>50%contribution of anthropogenic activities(GHGs)to annual monsoon precipitation changes.So,there is high confidence that monsoon precipitation in GBM has significantly changed due to anthropogenic activities.Different mitigation and adaption measures are also suggested,which may be adopted to manage the growing demand and water availability in the basin.展开更多
Energy is a basic requirement for development in the world.The continuously rising demand for energy resources and the fast depletion of fossil fuel is raises researcher's concern to focus on alternative sources o...Energy is a basic requirement for development in the world.The continuously rising demand for energy resources and the fast depletion of fossil fuel is raises researcher's concern to focus on alternative sources of energy that can replace the shortage of fossil fuels soon.Biodiesel is recognized as one of the potential alternative renewable energy fuels that can be easily available in a wide range in every part of the world.This paper reviews biodiesel's prospect and focuses on the different fuel properties(physicochemical)of 100 biodiesels from first-,second-and third-generation followed by the evaluation of CI engine characteristics.It has been observed that the fuel properties of first-,second-and third-generation biodiesel are compatible with the ASTM standards.The present paper discussed the potential of various generations of biodiesel feedstocks from production perspectives.This paper also examined many aspects of these feedstocks which include different biodiesel feedstock sources,biodiesel conversion technology,and second-generation biodiesel performance and emission characteristics.Most of the studies showed that biodiesel derived from plant feedstock is costly than diesel.Thus,more influence is to be given to non-edible sources.However,the engine characteristics are shown promising behavior with biodiesel and a slight increase in NOX is also reported on using various biodiesel.展开更多
The multiferroic Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3),(where M=Ba(DB),La(DL)and Pb(DP))has been synthesized by using solid-state reaction technique.Effects of Ba,La and Pb substitution on the structure,electri...The multiferroic Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3),(where M=Ba(DB),La(DL)and Pb(DP))has been synthesized by using solid-state reaction technique.Effects of Ba,La and Pb substitution on the structure,electrical and ferroelectric properties of Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3) samples have been studied by performing X-ray diffraction,dielectric and magnetic measurements.The crystal structures of the ceramic samples have a tetragonal phase.The vibrating sample magnetometer(VSM)measurement shows a significant change in the magnetic properties of Ba-doped Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3) as compared to La-and Pb-doped ceramics.It is seen that coercive field(HC)and remanent magnetization(MR)increases with Ba-doped ceramics but decreases for La-and Pbdoped ceramics.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0208)CAS Pioneer Hundred Talents Program.
文摘Ganga-Brahmaputra-Meghna(GBM)river basin is the third-largest and one of the most populated river basins in the world.As climate change is affecting most of the hydrometeorological variables across the globe,this study investigated the existence of climate change signal in all four climatological seasons in the GBM river basin and assessed the contribution of anthropogenic activities,i.e.,Greenhouse Gases(GHGs)emission in the change.Significant decreasing trends in the monsoon and a small increase in pre-monsoon precipitation were observed.Negligible change was detected in post-monsoon and winter season precipitation.CMIP5 GCMs were used for climate change detection,change point estimation,and attribution studies.Support Vector Machine(SVM)regression method was adopted to downscale GCM variables at the local scale.Monte-Carlo simulation approach was used to detect changes in different seasons.The climate change‘signals’were detectable after the year 1980 using Signal to Noise ratio(SNR)method in the majority of central and north-western regions.The change point was detectable only in annual monsoon precipitation at the basin level.Attribution analysis indicated>50%contribution of anthropogenic activities(GHGs)to annual monsoon precipitation changes.So,there is high confidence that monsoon precipitation in GBM has significantly changed due to anthropogenic activities.Different mitigation and adaption measures are also suggested,which may be adopted to manage the growing demand and water availability in the basin.
基金Seed Grant Fund No. [Dean (R&C) 19/1012] dated 14/08/2019 provided by MANIT Bhopal for supporting the research work
文摘Energy is a basic requirement for development in the world.The continuously rising demand for energy resources and the fast depletion of fossil fuel is raises researcher's concern to focus on alternative sources of energy that can replace the shortage of fossil fuels soon.Biodiesel is recognized as one of the potential alternative renewable energy fuels that can be easily available in a wide range in every part of the world.This paper reviews biodiesel's prospect and focuses on the different fuel properties(physicochemical)of 100 biodiesels from first-,second-and third-generation followed by the evaluation of CI engine characteristics.It has been observed that the fuel properties of first-,second-and third-generation biodiesel are compatible with the ASTM standards.The present paper discussed the potential of various generations of biodiesel feedstocks from production perspectives.This paper also examined many aspects of these feedstocks which include different biodiesel feedstock sources,biodiesel conversion technology,and second-generation biodiesel performance and emission characteristics.Most of the studies showed that biodiesel derived from plant feedstock is costly than diesel.Thus,more influence is to be given to non-edible sources.However,the engine characteristics are shown promising behavior with biodiesel and a slight increase in NOX is also reported on using various biodiesel.
基金Radheshyam Rai is grateful to the Foundation for Science and Technology of Portugal(FCT)for financial support(grant SFRH/BPD/38001/2007).
文摘The multiferroic Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3),(where M=Ba(DB),La(DL)and Pb(DP))has been synthesized by using solid-state reaction technique.Effects of Ba,La and Pb substitution on the structure,electrical and ferroelectric properties of Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3) samples have been studied by performing X-ray diffraction,dielectric and magnetic measurements.The crystal structures of the ceramic samples have a tetragonal phase.The vibrating sample magnetometer(VSM)measurement shows a significant change in the magnetic properties of Ba-doped Bi_(0.8)Gd_(0.1)M_(0.1)Fe_(0.9)Ti_(0.1)O_(3) as compared to La-and Pb-doped ceramics.It is seen that coercive field(HC)and remanent magnetization(MR)increases with Ba-doped ceramics but decreases for La-and Pbdoped ceramics.
