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Understanding arsenic behavior in alluvial aquifers:Evidence from sediment geochemistry,solute chemistry and environmental isotopes

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Geoscience Frontiers 2024年第5期15卷 222-238页

作者： Shailesh kumar Yadav AL.Ramanathan Chidambaram Sabarathinam Alok kumar Manoj kumar Anshula dhiman School of Environmental Sciences Jawaharlal Nehru UniversityNew Delhi 110067India Water Research Center Kuwait Institute for Scientific ResearchKuwait department of Environmental Studies University of Delhi110007India department of Earth and Environmental Sciences Indian Institute of Science Education and Research MohaliSector 81140306India

The hyd.o-geochemistry and isotopic variations in groundwater,coupled with sediment geochemistry,were investigated in the Middle Gangetic Plain,India,to better understand the aquifer dynamics that influence the arsenic(As)evolution and ***-four groundwater samples,thirteen River water samples,and two sediment cores(33 mbgl)were *** samples were analyzed for major ions and trace metals,including As and stable isotopic variability(δ^(2)H,δ^(18)o,andδ^(13)C).The study area was categorized into older and younger alluvium based.on existing geomorphological *** alluvium exhibits higher As enrichment in sediment and groundwater,ranging of 2.59–31.52 mg/kg and bdl to 0.62 mg/*** samples were thermodynamically more stable with As(oH)_(3)species ranging from 88.5%to 91.4%and FeooH from 69%to 81%,*** and mineralogical analysis suggested goethite and siderite act as a source and sink for ***,statistical analysis suggested reductive dissolution as the primary mechanism for As mobilization in the study ***-temporal analysis revealed elevated concentrations of As in the central and northeastern regions of the study *** isotope(δ^(2)H andδ^(18)o)analysis inferred active recharge conditions primarily driven by *** depleted d-excess value and enrichedδ^(18)o in the groundwater of younger alluvium indicate the effect of groundwater recharge with significant evaporation *** recharge potentially decreased the quantity of arsenic in groundwater,whereas evaporation enrichment increased *** infiltration during recharge introduces oxygenated water into the aquifer,leading to changes in the redox conditions and facilitating biogeochemical *** carbon isotope(δ^(13)C)results suggest that high microbial activity in younger alluvium promotes As leaching from sediment into the groundwater.

关键词： Groundwater recharge Reductive dissolution older alluvium Younger alluvium Ghazipur Stable isotope

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Refining aquifer heterogeneity and understanding groundwater recharge sources in an intensively exploited agrarian dominated region of the Ganga Plain

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Geoscience Frontiers 2024年第4期15卷 134-147页

作者： Abhinav Patel Shive Prakash Rai Nijesh Puthiyottil Abhinesh kumar Singh Jacob Noble Rajesh Singh dharmappa Hagare U.d.Saravana kumar Nachiketa Rai Kossitse Venyo Akpataku department of Geology Institute of ScienceBanaras Hindu UniversityVaranasiUttar Pradesh 221005India Isotope and Radiation Application division Bhabha Atomic Research CentreTrombayMumbai 400085India Environmental Hyd.ology division National Institute of HydrologyRoorkeeUttarakhand 247667India School of Engineering Design and Built EnvironmentWestern Sydney UniversityAustralia Isotope Hyd.ology Section Division of Physical and Chemical SciencesInternational Atomic Energy Agency(IAEA)ViennaAustria department of Earth Sciences Indian Institute of TechnologyRoorkeeUttarakhand 247667India Laboratory of organic Chemistry and Environmental Science Department of ChemistryUniversity of KaraPO Box 404KaraTogo

densely populated region of Ganga Plain is facing aquifer vulnerability through waterborne pollutants and groundwater stress due to indiscriminate abstraction,causing environmental and socio-economic *** address long-term groundwater resilience,it is crucial to understand aquifer heterogeneity and connectivity,groundwater recharge sources,effects of groundwater abstraction *** this con-text,present study aims to understand factors responsible for vertical and spatial variability of groundwater chemistry and to identify groundwater recharge sources in an intensively exploited agrarian region of the Ganga *** of chemometric,statistical,and isotopic analysis categorises the alluvial aquifer into zone 1(G1;ground surface to 100 m)and zone 2(G2;>100 m-210 m).The group G1 samples are characterized by a wide variation in hyd.ochemical species,noted with pockets of F-and No3-rich groundwater,and fresh to more evolved water types,while group G2 groundwater is characterized by a sharp increase in freshwater types and limited variation in their isotopic and hyd.ochemical *** G1 groundwater chemistry is governed by soil mineralogy,local anthropogenic inputs(So42-,Cl-,and No3-),and manifested by multiple recharge sources(local precipitation,river,canal water,pond).The G2 group is dominated by geogenic processes and mainly recharged by the local *** signatures confirm more evolved water type for group G1 in northwestern region,while fresh-water type covers the rest of the study *** rich groundwater is attributed to sodic water under alkaline conditions and enrichedδ18o values emphasizing role of evaporation in F-mobilization from micas and amphiboles abundant in the *** findings provide insight into potential groundwater vulnerability towards inorganic contaminants,and ground water recharge *** outcome of this study will help to develop aquifer resilience towards indiscriminate groundwater extrac

关键词： Stable isotopes Hyd.ogeochemical attributes Groundwater recharge sources Ganga Plain

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MXenes: Versatile 2d materials with tailored surface chemistry and diverse applications

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Journal of Energy Chemistry 2024年第3期90卷 253-293,I0008页

作者： Sunil kumar Nitu kumari Yongho Seo department of Nanotechnology and Advanced Materials Engineering and HMC Sejong UniversitySeoul 05006South Korea School of Studies in Chemistry Jiwaji UniversityGwalior 474011India

MXenes,the most recent addition to the 2d material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical strength,*** review begins by presenting MXenes,providing insights into their structural characteristics,synthesis methods,and surface functional *** review covers a thorough analysis of MXene surface properties,including surface chemistry and termination group *** properties of MXenes are influenced by their synthesis,which can be fluorine-based.or ***-based synthesis techniques involve etching with fluorine-based reagents,mainly including HF or LiF/HCl,while fluorine-free methods include electrochemical etching,chemical vapor deposition(CVd),alkaline etching,Lewis acid-based etching,*** techniques result in the emergence of functional groups such as-F,-o,-oH,-Cl,*** the MXenes surface,depending on the synthesis method *** of MXenes,such as electrical conductivity,electronic properties,catalytic activity,magnetic properties,mechanical strength,and chemical and thermal stability,are examined,and the role of functional groups in determining these properties is *** review delves into the diverse applications of MXenes,encompassing supercapacitors,battery materials,hyd.ogen storage,fuel cells,electromagnetic interference(EMI) shielding,pollutant removal,water purification,flexible electronics,sensors,additive manufacturing,catalysis,biomedical and healthcare fields,***,this article outlines the challenges and.opportunities in the current and future development of MXenes research,addressing various aspects such as synthesis scalability,etching challenges,and multifunctionality,and exploring novel *** review concludes with future prospects and conclusions envisioning the impact of MXenes on future technologies and innovation.

关键词： MXenes 2d materials Surface chemistry MXenes structure Synthesis Applications

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Bamboo resources of Sikkim Himalaya: diversity, distribution and utilization

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Journal of Forestry Research 2014年第4期25卷 929-934页

作者： d.o kumar tamang dinesh dhakal d. G. Shrestha Sikkim State Remote Sensing Application Centre Sikkim State Council of Science and Technology Development Area Gangtok 737101 Sikkim

We recorded 8 genera and.over 30 species of bamboo in Sikkim of the reported 23 genera and 125 species in Indi＆ Thirty percent of bamboo species were recorded in tropical forests （0-900 m）, 40% of species in sub-tropical forests （900-1,800 m）, 17% of species in temper- ate forests （1,800-2,700 m）, 9% of species in sub-alpine forests （2,700-3,500 m） and 4% of species in alpine vegetation （3,500-4,500 m）. Bamboo is used for various purposes and its versatility qualifies it to be a multiple-use alternative to timber, food for villagers and for tribal in particular. Bamboo is also equally important to Red Panda （Ailurusful- gens）, the state animal of Sikkim. We develop a list of bamboos occur- ring in Sikkim with their vernacular names, distributions and uses in the Himalayan state. However, more extensive study is required to fully describe the bamboo diversity of the Himalayan state.

关键词： bamboo dend.ocalamus diversity uses Sikkim

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Crystal structure and luminescence dynamics of highly pure LiM(Po_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting d.odes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij H.C.Swart Vinay kumar department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(Po_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(Po_(3))_(3) and LiCa(Po_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)d_(0)→^(7)F_(1).^(5)d_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(Po_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be d_(2) type for both *** photometric properties of LiCa(Po_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard.one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting d.odes.

关键词： Photoluminescence Phosphate WLEds Stark splitting Rare earths

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Metrology for sub-Rayleigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser Science and Engineering 2024年第3期12卷 90-105页

作者： E.A.Vishnyakov A.Sagisaka K.ogura T.Zh.Esirkepov B.Gonzalez-Izquierdo C.d.Armstrong T.A.Pikuz S.A.Pikuz W.Yan T.M.Jeong S.Singh P.Hadjisolomou o.Finke G.M.Grittani M.Nevrkla C.M.Lazzarini A.Velyhan T.Hayakawa Y.Fukuda J.K.Koga M.Ishino K.Kondo Y.Miyasaka A.Kon M.Nishikino Y.V.Nosach d.Khikhlukha I.P.Tsygvintsev d.kumar J.Nejdl d.Margarone P.V.Sasorov S.Weber M.Kando H.Kiriyama Y.Kato G.Korn K.Kondo S.V.Bulanov T.Kawachi A.S.Pirozhkov ELI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic Kansai Institute for Photon Science(KPSI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for open and Transdisciplinary Research Initiatives Osaka UniversityOsakaJapan HB11 Energy Holdings FreshwaterAustralia Key Laboratory for Laser Plasmas(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Physics ASCR PragueCzech Republic FZU-Institute of Physics ASCR PragueCzech Republic Czech Technical University in Prague FNSPEPragueCzech Republic Institute of Laser Engineering Osaka UniversityOsakaJapan Institute of Physics National Academy of Sciences of UkraineKyivUkraine ISTEQ AR YerevanArmenia

Tight focusing with very small f-numbers is necessary to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray diagnostics employed in a~10^(22)W/cm^(2)laser±plasma *** used nearly 10 J total energy femtosecond laser pulses focused into an approximately1.3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5μm accuracy(i.e.,around half of the short Rayleigh length)and show that several diagnostics(in particular,3ωreflection and.on-axis hard X-rays)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity *** approach is relatively fast(it requires 10±20 laser shots)and does not rely on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-rays

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Extracellular vesicles as tools and targets in therapy for diseases

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Signal Transduction and Targeted Therapy 2024年第3期9卷 872-912页

作者： Mudasir A.kumar Sadaf K.Baba Hana Q.Sadida Sara Al.Marzooqi Jayakumar Jerobin Faisal H.Altemani Naseh Algehainy Mohammad A.Alanazi Abdul-Badi Abou-Samra Rakesh kumar Ammira S.Al-Shabeeb Akil Muzafar A.Macha Rashid Mir Ajaz A.Bhat Watson-Crick Centre for Molecular Medicine Islamic University of Science and TechnologyAwantiporaKashmir 192122India department of Human Genetics-Precision Medicine in diabetes Obesity and Cancer ProgramSidra MedicineDohaQatar Qatar Metabolic Institute Academic Health SystemHamad Medical CorporationDohaQatar department of Medical Laboratory Technology Prince Fahad Bin Sultan Chair for Biomedical ResearchFaculty of Applied Medical SciencesUniversity of TabukTabukSaudi Arabia School of Biotechnology Shri Mata Vaishno Devi UniversityKatraIndia

Extracellular vesicles(EVs)are nano-sized,membranous structures secreted into the extracellular *** exhibit diverse sizes,contents,and surface markers and are ubiquitously released from cells under normal and pathological *** serum is a rich source of these EVs,though their isolation from serum proteins and non-EV lipid particles poses *** vesicles transport various cellular components such as proteins,mRNAs,miRNAs,dNA,and lipids across distances,influencing numerous physiological and pathological events,including those within the tumor microenvironment(TME).Their pivotal roles in cellular communication make EVs promising candidates for therapeutic agents,drug delivery systems,and disease *** in cancer diagnostics,EV detection can pave the way for early identification and.offers potential as diagnostic ***,various EV subtypes are emerging as targeted drug delivery tools,highlighting their potential clinical *** need for non-invasive biomarkers to monitor biological processes for diagnostic and therapeutic purposes remains *** into the unique composition of EVs could unlock advanced diagnostic and therapeutic avenues in the *** this review,we discuss in detail the roles of EVs across various conditions,including cancers(encompassing head and neck,lung,gastric,breast,and hepatocellular carcinoma),neurodegenerative disorders,diabetes,viral infections,autoimmune and renal diseases,emphasizing the potential advancements in molecular diagnostics and drug delivery.

关键词： diseases sized sizes

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Robust Facial Biometric Authentication System Using Pupillary Light Reflex for Liveness detection of Facial Images

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 725-739页

作者： Puja S.Prasad Adepu Sree Lakshmi Sandeep Kautish Simar Preet Singh Rajesh kumar Shrivastava Abdulaziz S.Almazyad Hossam M.Zawbaa Ali Wagdy Mohamed CSE department Geethanjali College of EngineeringHyderabadTelangana501301India department of Computer Science LBEF CampusKathmandu44600Nepal School of Computer Science Engineering and Technology(SCSET) Bennett UniversityGreater Noida201310India department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia CeAdAR Ireland’s Centre for AI Technological University DublinDublinD07 EWV4Ireland operations Research department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied Science Research Center Applied Science Private UniversityAmman11937Jordan

Pupil dynamics are the important characteristics of face spoofing *** face recognition system is one of the most used biometrics for authenticating individual *** main threats to the facial recognition system are different types of presentation attacks like print attacks,3d mask attacks,replay attacks,*** proposed model uses pupil characteristics for liveness detection during the authentication *** pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light *** proposed framework consists of two-phase *** the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different vid.o *** above measurement is converted into feature space using Kohn and Clynes model-defined *** Support Vector Machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,vid.o,or 3d mask of the subject in front of the *** the second phase,we perform the facial recognition ***-invariant feature transform(SIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional *** features are scale,rotation,and.orientation invariant and are used for recognizing facial *** brute force matching algorithm is used for matching features of two different *** threshold value we considered is 0.08 for good *** analyze the performance of the framework,we tested.our model in two Face antispoofing datasets named Replay attack datasets and CASIA-SURF datasets,which were used because they contain the vid.os of the subjects in each sample having three modalities(RGB,IR,depth).The CASIA-SURF datasets showed an 89.9%Equal Err

关键词： SIFT pupil CASIA-SURF pupillary light reflex replay attack dataset brute force

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Estimation of drift limits for different seismic damage states of RC frame staging in elevated water tanks using Park and Ang damage index

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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 161-177页

作者： Suraj o.Lakhade Ratnesh kumar o.R.Jaiswal department of Applied Mechanics Visvesvaraya National Institute of Technology

damage to elevated water tanks in past earthquakes can be attributed to the poor performance of their supporting frame staging. In order to ascertain the performance of these elevated water tanks, it is crucial to categorize the damage in quantifiable damage states. Among various parameters to quantify the damage states, the top drift of frame staging can be conveniently correlated to the different damage levels. In literature, drift limits corresponding to different damage states of the frame staging of the elevated water tank are not available. In the present study, drift limits for RC frame staging in elevated water tanks corresponding to different seismic damage states have been proposed. Various damage states of the elevated water tank have been determined using the Park and Ang damage index. The Park and Ang damage index utilizes results of both pushover analysis and incremental dynamic analysis. Twelve models of elevated water tanks have been developed considering variation in staging height and tank capacity. Incremental dynamic analysis has been performed using the suite of twelve actual earthquake ground motions. Based.on the regression analysis between damage indexes and drift, limiting drift values for each damage state are proposed.

关键词： elevated water tank frame staging damage states drift limit 3d modelling incremental dynamic analysis pushover analysis

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Multi-length scale modeling of carburization,martensitic microstructure evolution and fatigue properties of steel gears

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Journal of Materials Science & Technology 2020年第14期47卷 157-165页

作者： Edward Charles Henry Crawford.o’Brien Hemantha kumar Yeddu School of Engineering Newcastle UniversityNewcastle upon TyneNE17RUUnited Kingdom

Multi-length scale modeling is performed to(i)predict the carburized case depth of SAE8620 steel gears by solving the Fick’s second law of diffusion,(ii)model the martensitic microstructure evolution in a grain inside the carburized case as well as to study the effect of stress cycling on retained austenite(RA)and martensite using a 3d phase-field model,(iii)simulate the effect of carburization and different RA contents on macroscale fatigue behavior of SAE8620 steel spur gear using the finite element *** diffusion model predicts that the case depth increases with increasing heat treatment time and *** phase-field simulations show that RA can transform to martensite during fatigue loading,where the extent of the transformation will depend.on the type of stresses applied,*** in a high stress regime or low stress regime of fatigue *** transformation of martensite to austenite is also observed in low RA sample under high stress *** macroscale simulations show that the carburized case with high RA gives rise to better fatigue life compared to that with low RA.

关键词： Phase-field model Martensitic transformation Microstructure Gear steel Carburization

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