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Nanoscale resetting of the Th/Pb system in an isotopically-closed monazite grain: A combined atom probe and transmission electron microscopy study

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Geoscience Frontiers 2019年第1期10卷 65-76页

作者： A.-m.seydoux-Guillaume D.Fougerouse A.T.Laurent E.Gardés s.m.reddy D.W.saxey Univ Lyon UJM-Saint-Etienne CNRS IRD CNRs Université Clermont Auvergne school of Earth and Planetary sciences Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University Centre de recherche sur les Ions les Matériaux et la Photonique (CIMAP) Department of Physics and Astronomy Curtin University

Understanding the mechanisms of parent-daughter isotopic mobility at the nanoscale is key to rigorous interpretation of Ue The Pb data and associated dating. Until now, all nanoscale geochronological studies on geological samples have relied on either Transmission Electron microscope(TEm) or Atom Probe microscopy(APm) characterizations alone, thus suffering from the respective weaknesses of each technique. Here we focus on monazite crystals from a ~1 Ga, ultrahigh temperature granulite from Rogaland(Norway). This sample has recorded concordant UeP b dates(measured by LA-ICP-ms) that range over 100 my, with the three domains yielding distinct isotopic Ue Pb ages of 1034 ± 6 ma(D1; srich core), 1005 ± 7 ma(D2), and 935 ± 7 ma(D3), respectively. Combined APm and TEm characterization of these monazite crystals reveal phase separation that led to the isolation of two different radiogenic Pb(Pb*) reservoirs at the nanoscale. The s-rich core of these monazite crystals contains Cae srich clusters, 5 -10 nm in size, homogenously distributed within the monazite matrix with a mean interparticle distance of 40 -60 nm. The clusters acted as a sink for radiogenic Pb(Pb*) produced in the monazite matrix, which was reset at the nanoscale via Pb diffusion while the grain remained closed at the micro-scale. Compared to the concordant ages given by conventional micro-scale dating of the grain,the apparent nano-scale age of the monazite matrix in between clusters is about 100 myr younger, which compares remarkably well to the duration of the metamorphic event. This study highlights the capabilities of combined APm-TEm nano-structural and nano-isotopic characterizations in dating and timing of geological events, allowing the detection of processes untraceable with conventional dating methods.

关键词： monazite Nanoscale resetting Nano-clusters APm TEm UHT metamorphism

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Zircon geochronology reveals polyphase magmatism and crustal anatexis in the Buchan Block,NE scotland:Implications for the Grampian Orogeny

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Geoscience Frontiers 2017年第6期8卷 1469-1478页

作者： T.E.Johnson C.L.Kirkland D.R.Viete s.Fischer s.m.reddy N.J.Evans B.J.mcDonald Department of Applied Geology The Institute for Geoscience Research(TIGeR)CET-Curtin NodeJohn de Laeter CentreCurtin UniversityPerthWA 6102Australia morton K.Blaustein Department of Earth&Planetary sciences Johns Hopkins UniversityOlin Hall3400 N Charles StreetBaltimoreMD 21218USA school of Earth&Environmental science University of St AndrewsIrvine BuildingNorth StreetSt AndrewsKY16 9ALScotlandUK

The type locality for high-temperature,low-pressure regional metamorphism,the Buchan Block in NE scotland,exhibits profound differences to the rest of the Grampian *** differences have led some to regard the Buchan Block as an exotic crustal fragment comprising Precambrian basement gneisses and cover rocks thrust into their current position during Grampian *** rocks of the Buchan Block are now generally correlated with Dalradian strata elsewhere,the origin of the gneisses and the cause of the high heat flow and associated magmatism is *** report sIms U-Pb and LA-ICPms Hf isotopic data in zircon from high-grade rocks from the northeast(Inzie Head Gneiss)and northwest(Portsoy)corners of the Buchan *** Inzie Head,upper amphibolite to granulite facies metasedimentary gneisses coexist with diorite sheets that were emplaced contemporaneously with partial melting of their host rocks,at least locally.U-Pb geochronology indicates a crystallisation age for the diorite of 486±9 ***-deformed diorites within the Portsoy Gabbro have a crystallisation age of 493±8 *** of ca.490 ma for magmatism and high-grade metamorphism,which are broadly contemporaneous with ophiolite obduction and the onset of orogenesis,are significantly older than the established peak of Grampian metamorphism(ca.470 ma).We propose a new model for the Grampian Orogeny involving punctuated tectonothermal activity due to tectonic switching during accretionary *** of a NW-dipping subduction zone at ca.490 ma produced a back-arc environment(the Buchan Block)with associated arc magmatism and high dT/dP *** of an outboard arc resulted in shortening(the initial phase of the Grampian Orogeny)at ca.488 *** of a NW-dipping subduction zone to the sE of the ca.488 ma suture began at 473 ma and led to lithospheric-scale extension,decompression melting and advective heating of the middle crust,producing the widespread ca.470 ma Gram

关键词： Dalradian Grampian Orogeny Buchan Block Zircon geochronology magmatism metamorphism

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Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： P.s.reddy P.sREEDEVI Department of mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEPCms).The versatile finite element method(FEm)is implemented to numerically solve the governing *** effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEPCms,ranging from 2%to 6%,the stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented *** results indicate that the time taken by the NEPCms to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf ***,the contours of the heat capacity ratio Cr decrease with the increase in the stefan number ste.

关键词： volume fraction of nano-encapsulated phase change material(NEPCm) radiation stefan number heat capacity ratio entropy generation

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CompactChain:an efficient stateless chain for UTXO-model blockchain

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Frontiers of Computer science 2024年第2期18卷 167-179页

作者： B swaroopa reddy T Uday Kiran reddy Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)based blockchain systems into two RsA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called spent Transaction Output(sTXO)commitment which represents the sTXO *** this work,we discuss three algorithms:(i)To update the TXO and sTXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity by providing a membership witness in TXO commitment and non-membership witness against sTXO commitment for a coin being spent by a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPs)).

关键词： stateless blockchain RsA Accumulator sTXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPs)

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secure and efficient prediction of electric vehicle charging demand usingα^(2)-LsTm and AEs-128 cryptography

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Energy and AI 2024年第2期16卷 84-100页

作者： manish Bharat Ritesh Dash K.Jyotheeswara reddy A.s.R.murty Dhanamjayulu C. s.m.muyeen Department of Electrical and Electronics Engineering Visvesvaraya Technological UniversityBelgaumIndia school of Electrical and Electronics Engineering REVA UniversityBangaloreIndia school of Electrical Engineering Vellore Institute of TechnologyVelloreIndia Department of Electrical Engineering Qatar UniversityDoha2713Qatar

In recent years,there has been a significant surge in demand for electric vehicles(EVs),necessitating accurate prediction of EV charging *** prediction plays a crucial role in evaluating its impact on the power grid,encompassing power management and peak demand *** this paper,a novel deep neural network based onα^(2)-LsTm is proposed to predict the demand for charging from electric vehicles at a 15-minute time ***,we employ AEs-128 for station quantization and secure communication with *** proposed algorithm achieves a 9.2%reduction in both the Root mean square Error(RmsE)and the mean absolute error compared to LsTm,along with a 13.01%increase in demand *** present a 12-month prediction of EV charging demand at charging stations,accompanied by an effective comparative analysis of mean Absolute Percentage Error(mAPE)and mean Percentage Error(mPE)over the last five years using our proposed *** prediction analysis has been conducted using Python programming.

关键词： Charging demand forecasting Deep neural network Electric vehicles LsTm Peak demand management

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Comprehensive Overview and Analytical study on Automatic Bird Repellent Laser system for Crop Protection

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Journal of Harbin Institute of Technology(New series) 2024年第1期31卷 38-53页

作者： sireesha Abotula srinivas Gorla Prasad reddy PVGD mohankrishna s Department of Computer science and Engineering GITAM Deemed to be UniversityVisakhapatnam 530045India Department of Information Technology Andhra UniversityVisakhapatnam 530003India Department of Computer science and systems Engineering Andhra UniversityVisakhapatnam 530003India

Birds are a huge hazard to agriculture all around the world,causing harm to profitable field *** use a variety of techniques to keep them away,including visual,auditory,tactile,and olfactory deterrents. This study presents a comprehensive overview of current bird repellant approaches used in agricultural contexts,as well as potential new ways. The bird repellent techniques include Internet of Things technology,Deep Learning,Convolutional Neural Network,Unmanned Aerial Vehicles,Wireless sensor Networks and Laser biotechnology. This study’s goal is to find and review about previous approach towards repellent of birds in the crop fields using various technologies.

关键词： Bird repellent crop protection IoT UAV Deep Learning

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Entropy optimization on Casson nanofluid flow with radiation and Arrhenius activation energy over different geometries:A numerical and statistical approach

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Propulsion and Power Research 2024年第3期13卷 375-393页

作者： m.Priya P.Bala Anki reddy Department of mathematics S.A.S.Vellore Institute of TechnologyVellore 632014India

This study employs numerical and statistical approaches to investigate the entropy optimization of steady Casson nanofluidflow over three different geometries subject to boundary conditions induced by *** linear regression is employed to statistically *** present model incorporates several novel elements,such as Arrhenius activation energy,Brownian motion,the Cattaneo-Christov dualflux,thermophoresis,thermal radiation,and so ***,a comparison is presented between Newtonian and *** applying the proper similarity transformations,ordinary differential equations(ODEs)are ob-tained by converting foundational partial differential equations(PDEs).The Runge-Kutta fourth-order method is utilised to solve the obtained ODEs along with the shooting *** out-comes are visually depicted via tables and *** velocity drops with increasing Grashof number,and the magneticfield becomes progressively more forceful as the suction parameter *** temperature gets reduced with the increase of the suction parameter,solute Grashof number increases with the magneticfield,thermophoresis,and radiation *** entropy is observed to rise with the increase of the effective parameters(magneticfield,Brinkmann num-ber and radiation).The mAD(mean absolute deviation),msE(mean squared error),and RmsE(root mean square error)values are approaching zero,indicating that the derived outcomes are highly accurate.A lower mAPE(mean absolute percentage error)suggests that the model has a higher level of ***,the outcomes of the present model are more precise and *** study has various potential applications such as power plant heat exchangers,material processing industries,and solar thermal energy systems.

关键词： Cassonfluid Arrhenius activation energy Entropy generation Thermophoresis multiple linear regression

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Enhanced saturation magnetization in La^(3+) doped NiCo ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： maddileti Jelli Vidyasagar Thopudurthy Krishna reddy C.V. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Government PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)Co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FEsEm) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with m-O *** direct band measurements from ultraviolet-visible spectroscopy(UV-Vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 eV for x=0.05 to x=0.15,then increases to 1.28 eV for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(Vsm).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites sol-gel auto combustion La doping magnetic properties Rare earths

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Vitamin D, selenium in type 2 diabetes and Hashimoto's thyroiditis: Is it effective?

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World Journal of Diabetes 2024年第5期15卷 1048-1050页

作者： Kotha sugunakar reddy Vishakha Jain sakthivadivel Varatharajan Janardhana reddy Pallavali Department of General medicine All India Institute of Medical SciencesTelanganaHyderabad 508126India

The study by Feng et al,explores treatment approaches for these coexisting *** emphasizes the potential advantages of selenium and vitamin D supplementation but also raises methodological and patient selection *** indicate a complex interplay between interventions and disease markers,prompting the need for further *** limitations,the study offers valuable insights into managing the intricate relationship between type 2 diabetes mellitus and Hashimoto's *** authors'contributions shed light on potential treatment avenues,although careful consideration of study design and patient characteristics is warranted for future investigations in this domain.

关键词： Vitamin D selenium Type 2 diabetes mellitus Hashimoto’s thyroiditis

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Prediction,prevention and management of gastroesophageal reflux after per-oral endoscopic myotomy:An update

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World Journal of Gastroenterology 2024年第9期30卷 1096-1107页

作者： Zaheer Nabi Pradev Inavolu Nageshwar reddy Duvvuru Department of Gastroenterology Asian Institute of GastroenterologyHyderabad 500082TelanganaIndia Department of medical Gastroenterology Asian Institute of GastroenterologyHyderabad 500032TelanganaIndia

Achalasia cardia,the most prevalent primary esophageal motility disorder,is predominantly characterized by symptoms of dysphagia and *** principal therapeutic approaches for achalasia encompass pneumatic dilatation(PD),Heller's myotomy,and the more recent per-oral endoscopic myotomy(POEm).POEm has been substantiated as a safe and efficacious modality for the management of *** POEm demonstrates superior efficacy compared to PD and an efficacy parallel to Heller's myotomy,the incidence of gastroesophageal reflux disease(GERD)following POEm is notably higher than with the aforementioned *** symptomatic reflux post-POEm is relatively infrequent,the significant occurrence of erosive esophagitis and heightened esophageal acid exposure necessitates vigilant monitoring to preclude long-term GERD-related *** advancements in the field have enhanced our comprehension of the risk factors,diagnostic methodologies,preventative strategies,and therapeutic management of GERD subsequent to *** review focuses on the limitations inherent in the 24-h pH study for evaluating post-POEm reflux,potential modifications in the POEm technique to mitigate GERD risk,and the strategies for managing reflux following POEm.

关键词： Achalasia cardia Per-oral endoscopic myotomy Gastroesophageal reflux Esophagitis Gastroesophageal reflux disease

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