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Sequential decay analysis of^(235)U(n^(th),f)reaction using fragmentation approach

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Chinese Physics C 2024年第6期48卷 145-154页

作者： Nitin sharma Ashutosh Kaushik Manoj K.sharma School of Physics and Materials Science Thapar Institute of Engineering&TechnologyPatiala-147004PunjabIndia

Numerous experimental and theoretical observations have concluded that the probability of the three fragment emission(ternary fission)or binary fission increases when one proceeds towards the heavy mass region of nuclear periodic *** factors affect fragment emission,such as the shell effect,deformation,orientation,and fissility *** and ternary fissions are observed for both ground and excited states of the *** collinear cluster tripartition(CCT)channel of the^(235)U(n^(th),f)reaction is studied,and we observe that the CCT may be a sequential or simultaneous emission *** date,different approaches have been introduced to study the CCT process as a simultaneous or sequential process,but the decay dynamics of these modes have not been not fully *** the three fragments of the sequential process and exploring their related dynamics using an excitation energy dependent approach would be of further ***,in this study,we investigate the sequential decay mechanism of the^(235)U(n^(th),f)reaction using quantum mechanical fragmentation theory(QMFT).The decay mechanism is considered in two steps,where initially,the nucleus splits into an asymmetric *** the second step,the heavy fragment obtained in the first step divides into two *** I analysis is conducted by calculating the fragmentation potential and preformation probability for the spherical and deformed choices of the decaying *** most probable fragment combination of stage I are identified with respect to the dips in the fragmentation structure and the corresponding maxima of the preformation probability(P0).The light fragments of the identified decay channels(obtained in step I)agree closely with the experimentally observed *** excitation energy of the decay channel is calculated using an iteration *** excitation energy is shared using an excitation energy dependent level density *** obtained excitation

关键词： fission cluster radioactivity ternary fission spontaneous fission cluster model total kinetic energy preformation probability

Comprehending drivers of land use land cover change from 1999 to 2021 in the Pithoragarh District,Kumaon Himalaya,Uttarakhand,India

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Journal of Mountain Science 2024年第7期21卷 2394-2407页

作者： Mahika PHARTIYAL Sanjeev sharma Centre for the Study of Regional Development Jawaharlal Nehru UniversityNew Delhi 110067India

The Himalayan region has been experiencing stark impacts of climate change,demographic and livelihood pattern *** analysis of land use and land cover(LULC)change provides insights into the shifts in spatial and temporal patterns of *** changes are the combined effects of anthropogenic and natural/climatic *** present study attempts to monitor and comprehend the main drivers behind LULC changes(1999-2021)in the Himalayan region of Pithoragarh district,*** district is a border district,remotely located in the north-east region of Uttarakhand,*** study draws upon primary and secondary data sources.A total of 400 household surveys and five group discussions from 38 villages were conducted randomly to understand the climate perception of the local community and the drivers of *** imagery,CRU(Climatic Research Unit)climate data and climate perception data from the field have been used to comprehensively comprehend,analyze,and discuss the trends and reasons for LULC *** and remote sensing techniques were used to construct LULC *** multifaceted approach ensures comprehensive and corroborated *** classes were identified and formed viz-cultivation,barren,settlement,snow,and *** show that vegetation and builtup have increased whereas cultivation,barren land,and snow cover have *** study further aims to elucidate the causes behind LULC changes in the spatially heterogeneous region,distinguishing between those attributed to human activities,climate shifts,and the interconnected impacts of *** study provides a comprehensive picture of the study area and delivers a targeted understanding of local drivers and their potential remedies by offering a foundation for formulating sustainable adaptation policies in the region.

关键词： Himalayan region Land use/land cover change Anthropogenic factors Climate change Socioecological system

Hydrogen Spillover Effect in Electrocatalysis:Delving into the Mysteries of the Atomic Migration

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Energy & Environmental Materials 2024年第5期7卷 185-209页

作者： Ashish Gaur Jatin sharma HyukSu Han Department of Energy Science Sungkyunkwan University Institute of Nano Science and Technology Department of Energy Sungkyunkwan University

Hydrogen spillover effect has recently garnered a lot of attention in the field of electrocatalytic hydrogen evolution reactions. A new avenue for understanding the dynamic behavior of atomic migration in which hydrogen atoms moving on a catalyst surface was opened up by the setup of the word"hydrogen spillover."However, there is currently a dearth of thorough knowledge regarding the hydrogen spillover effect. Currently, the advancement of sophisticated characterization procedures offers progressively useful information to enhance our grasp of the hydrogen spillover effect. The understanding of material fabrication for hydrogen spillover effect has erupted. Considering these factors, we made an effort to review most of the articles published on the hydrogen spillover effect and carefully analyzed the aspect of material fabrication. All of our attention has been directed toward the molecular pathway that leads to improve hydrogen evolution reactions performance. In addition, we have attempted to elucidate the spillover paths through the utilization of DFT calculations. Furthermore, we provide some preliminary research suggestions and highlight the opportunities and obstacles that are still to be confronted in this study area.

关键词： electrocatalysis hydrogen evolution reaction hydrogen spillover effect interfacial atomic migration metal–support interaction

Study of plasma parameters of coaxial plasma source using triple Langmuir probe and Faraday cup diagnostics

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Plasma Science and Technology 2024年第4期26卷 94-100页

作者： Sunil KANCHI Rohit SHUKLA Archana sharma Pulsed Power and Electromagnetics Division Bhabha Atomic Research CentreVisakhapatnam 531011India Homi Bhabha National Institute Mumbai 400085India Beam Technology Development Group Bhabha Atomic Research CentreMumbai 400085India

Coaxial plasma guns are a type of plasma source that produces plasma which propagates radially and axially controlled by the shape of the ground electrode, which has attracted much interest in several applications. In this work, a 120° opening angle of CPG nozzle is used as a plasma gun configuration that operates at the energy of 150 J. The ionization of polyethylene insulator between the electrodes of the gun produces a cloud of hydrogen and carbon *** triple Langmuir probe and Faraday cup are used to measure plasma density and plasma temperature. These methods are used to measure the on-axis and off-axis plasma divergence of the coaxial plasma gun. The peak values of ion densities measured at a distance of 25 mm on-axis from the plasma gun are(1.6±0.5)×10^(19)m^(-3)and(2.8±0.6)×10^(19)m^(-3)for hydrogen and carbon plasma respectively and the peak temperature is 3.02±0.5 eV. The mean propagation velocity of plasma is calculated using the transit times of plasma at different distances from the plasma gun and is found to be 4.54±0.25 cm/μs and 1.81±0.18 cm/μs for hydrogen and carbon plasma respectively. The Debye radius is obtained from the measured experimental data that satisfies the thin sheath approximation. The shot-to-shot stability of plasma parameters facilitates the use of plasma guns in laboratory experiments. These types of plasma sources can be used in many applications like plasma opening switches, plasma devices, and as plasma sources.

关键词： coaxial plasma source triple Langmuir probe Faraday cup plasma density plasma temperature

Mitigating fire risks in hospitals:Are we primed and geared up?

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 141-142页

作者： Raman sharma Sruti sharma Department of Hospital Administration PGIMERChandigarhIndia Department of Hospital Administration Satellite CentreSangrurPGIMERChandigarhIndia

The recent incidents have confirmed that fires in COVID-19 hospitals have become a gruelling and nerve-testing challenge[1-3].The increased volumes of oxygen flow,abundance of inflammable alcohol sanitizers,wearing of inflammable kits,and abundance of equipment make it more acquiescent for such incidents and even difficult to *** density of equipment(especially ventilators)“enriches”air with oxygen,thereby increasing the“combustion risk”.

关键词： nit thereby control

A Comprehensive Review of Design and Technological Advancements across Various Types of Solar Dryers

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Energy Engineering 2024年第10期121卷 2851-2892页

作者： Ganesh There Rohit sharma School of Mechanical Engineering VIT Bhopal UniversitySehore466114India

This analysis investigates the widespread use of solar drying methods and designs in developing countries,particularly for agricultural products like fruits,vegetables,and bee *** techniques like hot air oven drying and open sun drying have drawbacks,including nutrient loss and exposure to harmful *** and thermal drying are viewed as sustainable solutions because they rely on renewable *** article highlights the advantages of solar drying,including waste reduction,increased productivity,and improved *** is also cost-effective and *** review study provides an overview of different solar drying systems and technologies used in poor nations,aiming to identify the most effective and efficient *** focus is on comparing current models of solar dryers for optimal *** review underscores the importance of solar drying as a long-term,eco-friendly approach to drying food in developing *** review aims to evaluate how using solar-powered drying techniques can enhance food preservation,minimize waste,and enhance the quality and marketability of agricultural *** paper will specifically focus on examining the efficacy of these methods for drying bee pollen and pinpointing where enhancements can be made in their advancement.

关键词： Renewable energy solar dryers open sun drying design parameters bee pollen drying

Effect of organic component(tartrate) addition on cerium nitrate's ability to inhibit corrosion of mild steel in NaCl solution

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Journal of Rare Earths 2024年第10期42卷 1995-2002页

作者： Minakshi Koundal Chhaya sharma A.K.Singh Department of Applied Science and Engineering Indian Institute of Technology RoorkeeSaharanpur CampusSaharanpurU.247001India Department of Pulp and Paper Technology Indian Institute of Technology Roorke Saharanpur CampusSaharanpurU.p247001India

Cerium tartrate(Cetar),produced in this study by precipitating cerium nitrate with potassium sodium tartrate(KNatar),was examined as a corrosion *** loss tests show inhibition efficiency of 71.7% with Ce(NO_(3))_(3) and 88.7% with Cetar inhibitor for one-month exposure to mild steel in 7 g/L NaCl *** inhibition efficiency drops to 28.6% with the fo rmer and remains around 8 7% with the latter inhibitor after six months of *** results from electrochemical testing indicate that the inhibition efficiency decreases by adding cerium ***,the cerium tartrate inhibitor demonstrates a nearly constant inhibition efficiency for up to 30 d,i.e.,≈90%.Electrochemical impedance spectroscopy(EIS) performed in these cases shows the following results:(ⅰ) with cerium nitrate,a film of iron and cerium oxide,which on prolonged exposure diminishes,and(ⅱ) with cerium tartrate,the formation of a bimetallic film(Fe-tartrate-Ce) and a mixture of cerium hydroxide and iro n oxide that protects steel for a longer *** inferences are based on the analyses of scanning electron microscopy/energydispersive X-ray analysis(SEM/EDAX),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron(XPS),and Raman spectroscopy results.

关键词： Cerium tartrate Cerium nitrate Corrosion inhibition Mild steel Inhibitor film characterization Rare earths

Process engineering of demineralisation of moderate to high ash Indian coals through NaOH‑HCl leaching and HF leaching

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International Journal of Coal Science & Technology 2024年第2期11卷 111-122页

作者： Heena Dhawan D.K.sharma ANRF Ministry of ScienceNew DelhiIndia Department of Energy Science and Engineering Indian Institute of Technology DelhiNew Delhi 110016India

Chemical leaching of coals would be required to produce cleaner coals for some special applications where physical benefi-ciation may not be effective *** would also help in recovering Li and rare earth metals besides in the sequestration of CO_(2).About 20 Indian coals having complexly distributed moderate to high ash contents were sequentially treated with various alkali–acid such as NaOH-HCl,HF,HCl,HCl-HF,and NaOH-HCl-HF *** aimed to establish and design the best stepwise sequential process for the highest degree of demineralisation through a chemical leaching *** and process intensification studies were carried *** than 80%demineralisation of Madhaipur and Neemcha coals was observed using the best sequential treatment designed *** repeated stepwise treatment of the alkali and the acid was also studied,which was found to significantly enhance the degree of demineralisation of *** integrated process of alkali–acid leaching followed by solvent extraction(Organo-refining)and vice versa of the treated coal was also studied for producing cleaner coals.

关键词： Alkali–acid leaching Demineralisation Integrated process Rare earth elements

Optimizing sampling frequency of surface and downhole measurements for efficient stick-slip vibration detection

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Petroleum 2024年第1期10卷 30-38页

作者： Saket Srivastava Aditya sharma Catalin Teodoriu Mewbourne School of Petroleum and Geological Engineering The University of OklahomaNormanOK73019USA

Drilling vibrations significantly impact drilling operations with high costs due to early downhole equipment failure and loss of productive ***-slip vibrations,a severe form of torsional vibrations,is known to be present up to 50%of total drilling time,making it a topic of immense concern and *** ongoing discussion in the industry is regarding the reliability of surface measurements for early detection of severe downhole bit ***,most surface measurements are sampled at lower frequency rates closer to 1 ***,the implementation of advanced data acquisition modules in downhole subs has greatly improved our understanding of drilling vibrations through high resolution data,sampled up to 10 ***,with a wide range of sampling frequency to choose from different available tools,a critical question remains *** is an optimal and adequate sampling frequency for early detection of downhole vibrations using both surface and downhole measurements?The paper addresses the question with a focus on stick-slip vibrations through an experimental *** slip tests are repeated for different sampling frequencies of surface and downhole measurements and the stick slip index for each case is *** stick-slip index varies for different sampling frequency even though the vibration tests remain completely *** was inferred that sampling frequency of measurements greatly impact the detection of downhole *** though stick-slip vibrations are characteristically low frequency vibrations(2Hz),a minimum of 10Hz sampling frequency is recommended for detection of stick-slip ***,all characteristics of stick-slip vibrations including bit sticking,bit RPM peaks and negative bit RPMs are clearly observed at a minimum of 100Hz sampling rate.

关键词： Drilling closer downhole