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Study of ZnO nanoparticle-supported clay minerals for electrochemical sensors,photocatalysis,and antioxidant applications

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ChemPhysMater 2024年第1期3卷 83-93页

作者： Mylarappa M N.Raghavendra N.R.b.umik. C.H.Chaithra b.N.Nagalaxmi k.N.Shravana k.mara Department of Chemistry Sri Jagadguru Renukacharya College of ScienceArts&CommerceBengaluru 560009India Department of Chemistry East West Institute of TechnologyBengaluru 560091India Department of Chemistry Maharani Lakshmi Ammanni College for WomenBengaluru 560012India

In view of the current study’s demonstration of the synthesis of clay-doped ZnO composites,we present a low-cost method for producing clay-metal oxide(clay/ZnO).Utilizing the solution comb.stion technique,a composite of clay/ZnO was produced utilizing citric acid as b.th a fuel and a complexing *** hexagonal unit cell structure of the created clay/ZnO may b. seen using XRD *** ZnO-infused clay was visib.e in FE-SEM micrographs as homogenous,sphere-shaped *** possib.e involvement of clay/ZnO photocatalytic activity in the UV-induced photodegradation of malachite green dye was *** 90%degradation rate shows the composite’s outstanding photocatalytic degradation *** resulting sub.tance was electrochemically analyzed using a constructed electrode in 0.1 M k.H *** increased its sensor capab.lities,which now include chemical and b.omolecule sensors,and it excelled in cyclic voltammetry-b.sed redox potential *** efficiently evaluate chemically synthesized NPs for electrochemical,sensing,and photocatalytic applications,this study intends to create a solution comb.stion procedure for the synthesis of clay/ZnO nanocomposite using urea as fuel.

关键词： Clay Clay/ZnO Photocatalytic Electrochemical sensors

Fluoride contamination in groundwater:A glob.l review of the status,processes,challenges,and remedial measures

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Geoscience Frontiers 2024年第2期15卷 1-29页

作者： E.Shaji k.V.Sarath M.Santosh P.k.k.ishnaprasad b.k.Arya Manisha S.b.b. Department of Geology University of KeralaKariavattom CampusThiruvananthapuramKerala 695581India School of Earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia Department of Geology Central University of KeralaTejaswini HillsPeriyeKasaragodKerala 671316India

Groundwater pollution b. fluoride is one of the prime concerns of the world population due to its toxicity,which results in adverse health *** this paper,we review the current scenario of the fluoride contamination of groundwater in various countries across the glob. and its impact on human *** the last decade,several newly affected regions have b.en reported all over the world,with more than 100 countries affected b. fluoride contamination in groundwater(concentration exceeding the acceptab.e limit of 1.5 mg/L defined b. the World Health Organization).Fluoride poisoning is mainly due to the unsupervised ingestion of products for dental and oral hygiene and over-fluoridated drink.ng *** is estimated that more than 200 million people from different countries are affected b. fluoriderelated groundwater issues and health *** highest among these are from the countries in Africa(38),Asia(28),and Europe(24),followed b. countries lik. South America(5),North America(3),and Australia(2).The source of fluoride in drink.ng water is primarily geogenic,together with forage,grasses and grains,tea,and anthropogenic *** countries affected were correlated with climatic zones and geological factors to gain insights into geospatial *** analyses show that most of the fluoride pollution-prone zones are located in high-grade metamorphic terranes with granitoid or alk.line intrusions,geothermal hot springs,and volcanic regions with arid or semi-arid climatic *** study also finds that children across the glob. are more vulnerab.e than adults to fluoride *** review finds that,although there are efficient fluoride removal techniques,including filters with next-generation nanomaterials,to date,there has not b.en a single technique developed that can claim to b. a practically rob.st solution for fluoride removal from drink.ng ***,we suggest developing next-generation filters that can retain essential miner

关键词： Fluoride Groundwater Water contamination WHO standards Climate zones Remediation Sustainab.e Development Goals

Two-dimensional　numerical　simulation　of　vertical　distrib.tions　of　dissolved　oxygen　in　Huanghai　Sea

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Acta Oceanologica Sinica 1997年第3期16卷 355-367页

作者： Liu k. Zhao b. Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

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关键词： simulation vertical distrib.tions numerical Huanghai Sea

Study of hyb.id nanofluid flow in a stationary cone-disk.system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN b.MAHANTHESH G.LORENZINI Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk.systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-b.sed Ag-Mg O hyb.id nanofluid in a static cone-disk.system while considering temperature-dependent fluid *** the variab.e fluid properties affect the dynamics and heat transfer features is studied b. Reynolds's linearized model for variab.e viscosity and Chiam's model for variab.e thermal *** single-phase nanofluid model is utilized to describ. convective heat transfer in hyb.id nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressib.lity condition.A self-similar model is developed b. the Lie-group scaling transformations,and the sub.equent self-similar equations are then solved *** influence of variab.e fluid parameters on b.th swirling and non-swirling flow cases is ***,the Nusselt numb.r for the disk.surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk.system,while the thermal conductivity parameter has the opposite effect.

关键词： hyb.id nanofluid cone-disk.system laminar flow variab.e fluid property Nusselt numb.r

Efficiency of Legumes in Increasing Yam Yield under Sandy Ferrasol in the Forest Zone of Southwestern Côte d’Ivoire

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Open Journal of Soil Science 2024年第4期14卷 227-236页

作者： Germaine A. Tanoh Félix b. O. b.uadou Jean b.ptiste D. Ettien Department of Soil Sciences Water and Geomaterials University of Felix Houphou&#235t Boigny Abidjan C&#244te d&#8217Ivoire Department of Food Security and Nutrition Swiss Center for Scientific Research in C&#244te d&#8217Ivoire Abidjan C&#244te d&#8217Ivoire

The cropping system is b.sed on traditional farming in rural areas. In this way, yields of some food crops lik. yam are very low considering their high need for nutrients. The nutrient-rich land is under high land pressure as it is occupied b. cash crops such as oil palm and rub.er at the expense of food crops and soil fertility is declining. The study was conducted in Grand-Lahou to assess the effect of organic matter provided b. legumes in increasing yam yield. The randomized complete b.ock.design included four (4) treatments: Arachis hypogaea + yam association (T1), Acacia mangium + yam association (T2), Arachis + Acacia mangium + yam association (T3) and pure yam crop (T0). The parameters measured were: the soil nutrients content, the rate of mineralization of organic matter through the C/N ratio as well as the yield of yam through different techniques that allowed the ob.ective of the study to b. achieved. It was noted a slight improvement of nitrogen and organic carb.n in all treatments with a higher value recorded in the T2 treatment. The C/N ratio decreased to 12 in all treatments compared to the control, which reflects a normal decomposition of the organic matter. Treatment T1 increased yam yield (8.4 t/ha) in contrast to treatments T2 (4.1 t/ha) and T3 (2.8 t/ha). Legume-b.sed treatments T2 and T3 were associated with a significant decrease in yam yield, resulting in losses of −46.34% to −25.09%, while treatment T1 resulted in a gain of 28.57%. As a result, the treatments involving legumes contrib.ted to normalizing the organic matter content of the soil. The simultaneous association of these two legumes led to a decrease in yam production, contrary to the treatment associating only groundnut.

关键词： Legumes Organic Matter Yam Yield Côte d’Ivoire

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite b.ffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivak.mar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a b.rnoulli process and the service time for the customers are *** the b.ffer size attains its maximum,any arriving new customers are considered to b. *** customers are served one b. one according to FCFS rule and each customers request random numb.r of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main ob.ectives of this article are to determine the service rates to b. employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed b.ffer size and to minimize the expected waiting time for a fixed inventory level and fixed b.ffer *** prob.ems are modelled as Mark.v decision *** estab.ish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the b.haviour of the model.

关键词： Queueing-inventory system discrete time b.tch demand-Mark.v decision process

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.Maroufi M.Daoud LPHE-MS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPMS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate b.tween quantum entanglement and quantum ***,this indistinguishab.lity is no longer holds for mixed *** contrib.te to a b.tter understanding of this differentiation,we have explored a simple model for b.th generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fab.y–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations b.yond entanglement b.tween these mechanical *** k.y ingredient in analyzing quantum correlation in this system is the glob.l covariance *** forms the b.sis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to b. a more suitab.e metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul b.Wignall David P.G.b.nd School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were b.dly affected, especially amongst the b.nthos(e.g. b.achiopods, corals, b.yozoans, foraminifers,ostracods). Plank.onic populations underwent a fundamental change with euk.ryotic algae b.ing replaced b. nitrogen-fixing b.cteria, green-sulphur b.cteria, sulphate-reducing b.cteria and prasinophytes. Detailed studies of b.undary sections, especially those in South China, have resolved the crisis to a ～55 k.r interval straddling the Permo-Triassic b.undary. Many of the losses occur at the b.ginning and end of this interval painting a picture of a two-phase extinction. Improved k.owledge of the extinction has b.en supported b. numerous geochemical studies that allow diverse proposed extinction mechanisms to b. studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections glob.lly, although the intensity and timing shows regional variab.lity. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attrib.te the losses to b.th anoxia and high *** k.ll mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less lik.ly, siltation(b.rial under a massive influx of terrigenous sediment) which lack. sub.tantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was lik.ly Sib.rian Trap eruptions and their associated carb.n dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Sib.rian volcanism have also b.en link.d to the crisis, b.t the short-term nature of these episodes(k.s this an unlik.ly cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern b.real latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert P.Hesselb.ch M.Schorner V.b.gnoud R.b.lik.v P.Drechsel b.Heuser O.SHumphries P.k.trik.b.Lindqvist C.Qu R.Redmer D.Riley G.Schaumann S.Schumacher A.Tauschwitz D.Varentsov k.Weyrich X.Yu b.Zielb.uer Zs.Major P.Neumayer D.k.aus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL Gmb. Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für k.rnphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State k.y Lab.ratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 k.in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,b.tdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a sub.tantially increased intensity of the heavy ion b.am will b. availab.e.

关键词： heated intense structure