The interaction of high-power laser pulses with undercritical foams produced by different techniques but with the same average density is studied at the PALS laser facility.The spatial-temporal evolution of X-ray emis...The interaction of high-power laser pulses with undercritical foams produced by different techniques but with the same average density is studied at the PALS laser facility.The spatial-temporal evolution of X-ray emission is observed using an X-ray streak camera,electron and ion temperatures are measured by X-ray spectroscopy,and hot-electron production is characterized by monochromatic X-ray imaging.Transmission of a femtosecond laser probe pulse through foams is observed in the near and far fields.In spite of large differences in pore size and foam structure,the velocity of ionization front propagation is quite similar for all the foams studied and is slower than that in a homogeneous material of the same average density.The ion temperature in the plasma behind the ionization front is a few times higher than the electron temperature.Hot-electron production in plastic foams with small pores is strongly suppressed compared with that in solid targets,whereas in foams produced by additive manufacturing,it is significantly increased to the level observed in bare copper foil targets.展开更多
The kinetics of mild steel corrosion in aqueous acetic acid solution has been investigated by weight loss and polarization techniques at 25,35 and 45℃.The weight loss of mild steel at room temperature （25℃） has be...The kinetics of mild steel corrosion in aqueous acetic acid solution has been investigated by weight loss and polarization techniques at 25,35 and 45℃.The weight loss of mild steel at room temperature （25℃） has been found to be quite significant,indicating poor corrosion resistance in acetic acid.The maximum corrosion rate has been observed in 25% acetic acid solution at all three experimental temperatures.The decrease in corrosion rate after attaining a maximum value has been attributed to the deposition of corrosion product on the surface.Anodic polarization curves exhibit active behaviour at each concentration and temperature with a shift towards higher current density region and increased corrosion rates at higher temperatures.The cathodic polarization curves are almost identical irrespective either of the concentration of acetic acid or temperature.The results obtained by both the techniques are in good agreement,while the surface studies support the conclusions drawn from the weight loss method.展开更多
Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development...Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development,tunneling and hydroelectric power projects and climate change.The parameters which are more crucial among these are a matter of scientific study and analysis.This research,taking Solan district,Himachal Pradesh,India,as the study area,aims to assess the impact of anthropogenic activities on landslide susceptibility at a regional scale.Landslide distribution was characterized into two groups,namely Rainfall-Induced Landslide(RIL)and Human-Induced Landslide(HIL)based on triggering factors.Multiple data such as slope angle,aspect,profile curvature,distance to drainage,distance to lineament,lithology,distance to road,normalized difference vegetation index(NDVI)and land use land cover(LULC)have been considered for delineating the landslide susceptibility zonation(LSZ)map.The effect of anthropogenic activities on landslide occurrences has been examined through the distribution of landslides along national highways and land use land cover changes(LULCC).Two sets of LSZ maps with a LULC of time interval covering five years(2017&2021)were prepared to compare the temporal progression of LULC and landslide susceptibility during the five years.The results indicated the significant impact of anthropogenic activities on the landslide susceptibility.LSZ map of the year 2021 shows that 23%area falls into high and very high susceptible classes and 48%area falls into very low and low susceptibility classes.Compared to LSZ map of 2017,high and very high susceptible classes have been increased by 15%,whereas very low and low susceptible classes have been reduced by 7%.The present case study will help to understand the potential driving parameters responsible for HIL and also suggest the inclusion of LULC in landslide susceptibility analysis.The study will demonstrate new opportunities for research that could help decision-makers prepare for future disasters,both in the Indian Himalayan region and other areas.展开更多
An account of 20 species under 11 genera of the family Fabaceae is presented based upon a thorough study of the collected specimens and field surveys in this paper from Sechu Tuan Nalla Wildlife Sanctuary,Chamba distr...An account of 20 species under 11 genera of the family Fabaceae is presented based upon a thorough study of the collected specimens and field surveys in this paper from Sechu Tuan Nalla Wildlife Sanctuary,Chamba district,Himachal Pradesh.Of these,five taxa are reported first time from the Chamba district of the state.The updated nomenclature of the species,local name if any,a brief description of the plant,flowering and fruiting period,distribution in the study area,habitat and ecology and specimen examined have been provided.展开更多
Industry 4.0 is one of the hot topic of today’s world where everything in the industry will be data driven and technological advancements will take place accordingly.In the fourth phase of industrial revolution,manuf...Industry 4.0 is one of the hot topic of today’s world where everything in the industry will be data driven and technological advancements will take place accordingly.In the fourth phase of industrial revolution,manufacturers are dependent upon data produced by the consumers to invent,innovate or change anything for the product.Internet of things devices like OBD,RFID,IIoT,Smart devices are the major source of data generation and represents trends in the industry.Since the IoT device are vulnerable to hackers due to its limitation,consumer data security should be tighten up and enhanced.This paper gives an overview of industrial revolutions as well as proposes Blockchain Cloud Computing as a solution to store data for Industry 4.0.展开更多
Inspired by the structural adaptations of natural biological organisms,helicoidal composite architectures have shown significant potential for enhancing toughness,strength,and weight efficiency in engineering applicat...Inspired by the structural adaptations of natural biological organisms,helicoidal composite architectures have shown significant potential for enhancing toughness,strength,and weight efficiency in engineering applications.However,temperature and moisture's adverse effects pose challenges during service,potentially compromising their overall performance.This study meticulously analyzes the buckling and vibration behavior of carbon nanotube(CNT)-reinforced bioinspired helicoidal composite plates under different hygrothermal conditions.A novel aspect of this study lies in the proposition of a multiscale analysis combining the analytical and numerical techniques to assess the effects of temperature,moisture,weight fraction of CNTs,layup configurations of bioinspired designs,aspect ratios,loading and boundary conditions,and geometric shapes of bioinspired helicoidal composite structures on their vibration and buckling characteristics.In this context,the stiffness properties are computed with the Halpin-Tsai model,incorporating the size-dependent features of CNTs along with their waviness and agglomeration.In addition,the Chamis micro-mechanical equations are used to determine the elastic properties of individual layers constituting bioinspired composites,considering the effects of temperature and moisture.The kinematics of the laminated bioinspired structures are captured with the third-order shear deformation theory(TSDT)within the isogeometric framework employing the non-uniform rational B-splines(NURBSs)as the basis functions.The isogeometric framework ensures higher-order inter-element continuity and provides an exact geometric representation,offering various advantages over the traditional finite element method.The developed framework is validated against the existing literature,and thereafter several numerical examples are presented,providing valuable insights for the design and optimization of bioinspired composite structures,with potential benefits for various engineering fields,including marine and aerospace sectors.展开更多
基金supported by the Center of Advanced Applied Sciences(CAAS)Project No.(CZ.02.1.01/0.0/0.0/16019/0000778)from the European Regional Development Fundalso supported in part by the Czech Technical University in Prague Project No.SGS22/184/OHK4/3T/14+1 种基金partial funding via EUROfusion Enabling Research Project No.AWP24-ENR-03-CEA-02“Foams as a pathway to energy from high gain direct drive ignition,”within the framework of the EUROfusion Consortium,funded by the European Union via the Euratom Research and Training Program(Grant Agreement No.101052200-EUROfusion)the Czech Ministry of Education,Youth and Sports(CMEYS)for funding the operation of the PALS facility(Grant No.LM2023068)。
文摘The interaction of high-power laser pulses with undercritical foams produced by different techniques but with the same average density is studied at the PALS laser facility.The spatial-temporal evolution of X-ray emission is observed using an X-ray streak camera,electron and ion temperatures are measured by X-ray spectroscopy,and hot-electron production is characterized by monochromatic X-ray imaging.Transmission of a femtosecond laser probe pulse through foams is observed in the near and far fields.In spite of large differences in pore size and foam structure,the velocity of ionization front propagation is quite similar for all the foams studied and is slower than that in a homogeneous material of the same average density.The ion temperature in the plasma behind the ionization front is a few times higher than the electron temperature.Hot-electron production in plastic foams with small pores is strongly suppressed compared with that in solid targets,whereas in foams produced by additive manufacturing,it is significantly increased to the level observed in bare copper foil targets.
文摘The kinetics of mild steel corrosion in aqueous acetic acid solution has been investigated by weight loss and polarization techniques at 25,35 and 45℃.The weight loss of mild steel at room temperature （25℃） has been found to be quite significant,indicating poor corrosion resistance in acetic acid.The maximum corrosion rate has been observed in 25% acetic acid solution at all three experimental temperatures.The decrease in corrosion rate after attaining a maximum value has been attributed to the deposition of corrosion product on the surface.Anodic polarization curves exhibit active behaviour at each concentration and temperature with a shift towards higher current density region and increased corrosion rates at higher temperatures.The cathodic polarization curves are almost identical irrespective either of the concentration of acetic acid or temperature.The results obtained by both the techniques are in good agreement,while the surface studies support the conclusions drawn from the weight loss method.
文摘Landslides in the Himalayan region are primarily controlled by natural parameters,including rainfall,seismic activity,and anthropogenic parameters,such as the construction of large-scale projects like road development,tunneling and hydroelectric power projects and climate change.The parameters which are more crucial among these are a matter of scientific study and analysis.This research,taking Solan district,Himachal Pradesh,India,as the study area,aims to assess the impact of anthropogenic activities on landslide susceptibility at a regional scale.Landslide distribution was characterized into two groups,namely Rainfall-Induced Landslide(RIL)and Human-Induced Landslide(HIL)based on triggering factors.Multiple data such as slope angle,aspect,profile curvature,distance to drainage,distance to lineament,lithology,distance to road,normalized difference vegetation index(NDVI)and land use land cover(LULC)have been considered for delineating the landslide susceptibility zonation(LSZ)map.The effect of anthropogenic activities on landslide occurrences has been examined through the distribution of landslides along national highways and land use land cover changes(LULCC).Two sets of LSZ maps with a LULC of time interval covering five years(2017&2021)were prepared to compare the temporal progression of LULC and landslide susceptibility during the five years.The results indicated the significant impact of anthropogenic activities on the landslide susceptibility.LSZ map of the year 2021 shows that 23%area falls into high and very high susceptible classes and 48%area falls into very low and low susceptibility classes.Compared to LSZ map of 2017,high and very high susceptible classes have been increased by 15%,whereas very low and low susceptible classes have been reduced by 7%.The present case study will help to understand the potential driving parameters responsible for HIL and also suggest the inclusion of LULC in landslide susceptibility analysis.The study will demonstrate new opportunities for research that could help decision-makers prepare for future disasters,both in the Indian Himalayan region and other areas.
文摘An account of 20 species under 11 genera of the family Fabaceae is presented based upon a thorough study of the collected specimens and field surveys in this paper from Sechu Tuan Nalla Wildlife Sanctuary,Chamba district,Himachal Pradesh.Of these,five taxa are reported first time from the Chamba district of the state.The updated nomenclature of the species,local name if any,a brief description of the plant,flowering and fruiting period,distribution in the study area,habitat and ecology and specimen examined have been provided.
文摘Industry 4.0 is one of the hot topic of today’s world where everything in the industry will be data driven and technological advancements will take place accordingly.In the fourth phase of industrial revolution,manufacturers are dependent upon data produced by the consumers to invent,innovate or change anything for the product.Internet of things devices like OBD,RFID,IIoT,Smart devices are the major source of data generation and represents trends in the industry.Since the IoT device are vulnerable to hackers due to its limitation,consumer data security should be tighten up and enhanced.This paper gives an overview of industrial revolutions as well as proposes Blockchain Cloud Computing as a solution to store data for Industry 4.0.
文摘Inspired by the structural adaptations of natural biological organisms,helicoidal composite architectures have shown significant potential for enhancing toughness,strength,and weight efficiency in engineering applications.However,temperature and moisture's adverse effects pose challenges during service,potentially compromising their overall performance.This study meticulously analyzes the buckling and vibration behavior of carbon nanotube(CNT)-reinforced bioinspired helicoidal composite plates under different hygrothermal conditions.A novel aspect of this study lies in the proposition of a multiscale analysis combining the analytical and numerical techniques to assess the effects of temperature,moisture,weight fraction of CNTs,layup configurations of bioinspired designs,aspect ratios,loading and boundary conditions,and geometric shapes of bioinspired helicoidal composite structures on their vibration and buckling characteristics.In this context,the stiffness properties are computed with the Halpin-Tsai model,incorporating the size-dependent features of CNTs along with their waviness and agglomeration.In addition,the Chamis micro-mechanical equations are used to determine the elastic properties of individual layers constituting bioinspired composites,considering the effects of temperature and moisture.The kinematics of the laminated bioinspired structures are captured with the third-order shear deformation theory(TSDT)within the isogeometric framework employing the non-uniform rational B-splines(NURBSs)as the basis functions.The isogeometric framework ensures higher-order inter-element continuity and provides an exact geometric representation,offering various advantages over the traditional finite element method.The developed framework is validated against the existing literature,and thereafter several numerical examples are presented,providing valuable insights for the design and optimization of bioinspired composite structures,with potential benefits for various engineering fields,including marine and aerospace sectors.
