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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1663-1674页

作者： j.MACKOLIL b.MAHANTHESH Centre for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Bengaluru 560029KarnatakaIndia

The heat transfer rate of the thermal Marangoni convective flow of a hybrid nanomaterial is optimized by using the response surface methodology(RSM).The thermal phenomenon is modeled in the presence of a variable inclined magnetic field,thermal radiation,and an exponential heat *** estimated values of the thermal conductivity and viscosity of the hybrid nanomaterial are utilized in the *** governing intricate nonlinear problem is treated numerically,and a parametric analysis is carried out by using graphical visualizations.A finite difference-based numerical scheme is utilized in conjunction with the 4-stage Lobatto IIIa formula to solve the nonlinear governing *** interactive effects of the pertinent parameters on the heat transfer rate are presented by plotting the response surfaces and the contours obtained from the *** mono and hybrid nanomaterial flow fields are *** hybrid nanomaterial possesses enhanced thermal fields for nanoparticle volume fractions less than 2%.The irregular heat source and the thermal radiation enhance the temperature *** high level of the thermal radiation and the low levels of the exponential heat source and the angle of inclination(of the magnetic field)lead to the optimized heat transfer rate(Nux=7.46275).

关键词： inclined magnetic field Marangoni boundary layer flow sensitivity analysis hybrid nanofluid exponential heat source response surface methodology(RSM)

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Applied Mathematics(A journal of Chinese Universities) 2019年第2期34卷 229-252页

作者： j Dhivya b Sridevi Department of Mathematics Kumaraguru College of TechnologyCoimbatoreTamil NaduIndia Department of Mathematics PSG College of TechnologyCoimbatoreTamil NaduIndia

Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers is proposed. The proposed similarity measure provides reasonable results not only for the sets available in the literature but also gives very reasonable results, especially for fuzzy sets as well as for most intuitionistic fuzzy sets. To provide supportive evidence, the proposed similarity measure is tested on certain sets available in literature and is also applied to pattern recognition and medical diagnosis problems. It is observed that the proposed similarity measure provides a very intuitive quantification.

关键词： Fuzzy sets (FSs) Intuitionistic fuzzy sets (IFSs) Most intuitionistic fuzzy sets (MIFSs) Simi- larity measure (SM) Transformed triangular fuzzy numbers (TTFNs)

Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： b.j.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

Tracking moving magnetic features in the photosphere

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1737-1748页

作者： bCHNER jrg Max-Planck-Institut fr Sonnensystemforschung

This research aims for an objective identification, tracking, and a statistical analysis of the Moving Magnetic Features (MMFs) around sunspots using SOHO/MDI high-resolution magnetograms. To this end, we develop a computerized tracking program and study the motion and magnetism of the outflows of MMFs around 26 sunspots. Our method locates 4-27 MMFs per hour, with higher counts for large sunspots. We differentiate MMFs into type α that have a polarity opposite to the parent sunspots, and type β that share the sunspot's polarity. These sunspots' MMF subsets exhibit a wide range of central tendencies which have distinctive correlations with the sunspots. In general, α-MMFs emerge farther from the sunspot, carry less flux, and move faster than β-MMFs. The typical α/β-MMFs emerge at 2.2 - 8.1/0.1 - 3.2 Mm outside the penumbra limb, with lifetimes of 1.1 - 3.1/1.3 - 2.0 h. They are 1.1 - 6.6/1.4 - 3.6 Mm2 in area and carry 1.4 - 12.5/4.8 - 11.4 ×1018 Mx of flux. They travel a distance of 2.7 - 5.9/2.8 - 3.6 Mm with the speed of 0.5 - 0.9/0.4 - 0.7 km/s. Compared to the α-MMFs produced by large sunspots, those of small spots are smaller. They emerge closer to sunspot, move farther, live longer, and carry less flux. β-MMFs show much less correlation with the sunspots. The flux outflow carried by the MMFs ranges from 0.2 to 8.3 × 1019Mx· h-1 and does not show obvious correlation with the sunspots' evolution. The frequency distributions of the MMFs' distance traveled, area, and flux are exponential. This suggests the existence of numerous small, weak, and short-timescale magnetic objects which might contribute to the sunspot flux outflow.

关键词： sun activity magnetic fields photosphere sunspots moat moving magnetic features

Laser induced photo-detachment of O2 in DC discharge

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Plasma Science and Technology 2018年第7期20卷 98-105页

作者： j r legorreta j l patiNo f b yousif Centro de Investigacion en Ciencias Universidad Autonoma del Estado de Morelos.Av.UniversidadNo.1001 Col.Chamilpa Cuemavaca MorelosMexico

Determination of the negative ion number density of O2 and O in a DC discharge of oxygen plasma was made employing Langmuir probe in conjunction with eclipse laser photo- detachment technique. The temporal evolution of the extra electrons resulting from the photo- detachment of O2- and O- were used to evaluate the negative ion number density. The ratio of O2 number density to O varied from 0.03 to 0.22. Number density of both O~ and O increased with increasing power and decreased as the pressure was increased. Electron number density was evaluated from the electron energy distribution function （EEDF） using the I-V recorded characteristic curves. Electron temperature between 2 and 2.7 eV were obtained. Influence of the 02（al△g） metastable state is discussed.

关键词： electronegative plasma electron temperature Langmuir probe negative ion number density

Impact of La^(3+)substitution on electrical,magnetic,dielectric and optical properties of Ni_(0.7)Cu_(0.1)Zn_(0.2)LaxFe_(2-x)O_(4)(0

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journal of Rare Earths 2023年第5期41卷 740-746,I0004页

作者： b.b.Patil A.D.Pawar S.S.barate j.S.Ghodake j.b.Thorat T.j.Shinde P.G.Department of Physics Smt.KRP Kanya MahavidyalayaIslampurMS415409India Department of Physics Shivaji UniversityKolhapurMS416004India Departments of Physics PDVP MahavidyalayaMahavidyalayaTasgaonMS416312India Department of Physics Sadguru Gadage Maharaj CollegeKaradMS415110

The oxalate co-precipitation method was used to synthesize the La3+substituted Ni-Cu-Zn(La-NCZ)nanoferrites having chemical composition Ni_(0.7)Cu_(0.1)Zn_(0.2)LaxFe_(2-x)O_(4)(x=0.015,0.025 and 0.035).DC resistivity study of nanoferrites shows both the conducting and semiconducting *** room temperature DC electrical resistivity of Ni-Cu-Zn(NCZ)nanoferrites decreases,whereas Curie temperature increases with increasing La^(3+)*** the temperature range of 30-170℃nanoferrites show p-type semiconducting behavior except x=0.015;thereafter,they show n-type *** frequency dispersive initial permeability(μi)associated with its real and imaginary(μ’andμ")parts are attributed to the domain wall movement and magnetic spin ***μi,u’andμ"of La-NCZ nanoferrites are higher than those of pure NCZ *** constant(ε’),dielectric loss(ε")and AC resistivity(ρAC)of La-NCZ nanoferrites show normal dielectric *** is found thatε’of NCZ nanoferrites decreases with the increasing content of La3+*** bandgap energy of La-NCZ nanoferrites is achieved in the range 1.36-1.70 eV confirming the semiconducting nature of materials.

关键词： Ni-Cu-La-Zn nanoferrites DC electrical Resistivity Permeability Dielectric properties bandgap energy Rare earths

Deposition of Nano-Scaled Coatings Using Inductively Coupled Plasma

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journal of Rare Earths 2004年第Z2期22卷 153-156页

作者： D H jung b Park j j Lee School of Materials Science and Engineering College of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea

Nano-scaled Ti-b-N coatings could be produced by inductively coupled plasma (ICP) assisted magnetron spurtering. The properties and microstructure of the coating can be changed drastically by applying ICP to conventional magnetron sputtering. In this work, an internal type rf ICP process is used. The core of this technology is the efficient production and control of self-depositing ions and reactive gas ions by an induced electric field. Ti-b-N coatings were prepared by using a Tib2 target and a gas mixture of N2 and Ar at 200 ℃ and a pressure of 60 mTorr. In addition to ICP, the effect of the substrate bias voltage on the structure and properties of the coating was investigated. by applying ICP and a bias voltage to the substrate the hardness of the Ti-b-N coating is increased by more than 75 GPa, as a result of enhanced ionization in the plasma. The Ti-b-N coating, which has the highest hardness, shows the best surface uniformity and a very dense structure with a grain size of 3 nm. This sample also shows a high crystallinity compared to the coating prepared using other deposition parameters.

关键词： nano-scaled coatings industively conpled plasma

Uniform Query Framework for Relational and NoSQL Databases

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Computer Modeling in Engineering & Sciences 2017年第2期113卷 171-181页

作者： j.b.Karanjekar M.b.Chandak Shri Ramdeobaba College of Engineering and Management NagpurIndia and Izel Technologies Pvt Ltd.PuneIndia Shri Ramdeobaba College of Engineering and Management NagpurIndia

As the data managed by applications has evolved over the years with the arrival of Web 2.0,a large number of new databases have been developed to manage various types of *** the traditional relational databases continue to exist,NoSQL databases which are document oriented or key-value stores or columnar continue to evolve and are embraced very rapidly across the *** is not just the type of data handled by these databases that is different but also the query language they use is also *** paper talks about a uniform query framework that can be used for traditional relational databases and NoSQL *** query framework can also perform joins,aggregates,filter on data from various data sources in a single query.

关键词： NoSQL RDbMS data tetrieval inter-database joins SQL Cassandra MongoDb Calcite MySQL

UV/visible spectroscopic analysis of CO^(3+) and CO^(2+) during the dissolution of cobalt from mixed Co-Cu oxidized ores

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International journal of Minerals,Metallurgy and Materials 2011年第3期18卷 260-269页

作者： j. Ndalamo A.F. Mulaba-bafubiandi b.b. Mamba Department of Chemical Technology University of Johannesburg Department of Extraction Metallurgy University of Johannesburg

The leaching of cobalt from four-mixed Co-Cu oxidized ores containing cobalt at levels ranging from 0.5wt% to 34wt% was studied and the results has been reported. Conventional dissolution of these oxidized Co-Cu ores with diluted H2SO4 and SO2 as a reducing agent resulted in a substantial improvement in the solution based recovery of cobalt. UV/visible spectroscopic analysis of the leached solu-tions indicated that the increased cobalt content in the solution was a result of flushing the acidified cobalt leaching solution with SO2. Fur-thermore, UV/visible spectroscopy confirmed that as SO2 was flushed into the acidified leaching solution, Co3＋ bearing minerals were re-duced to the readily soluble Co2＋ bearing minerals, and this resulted in the increase of total cobalt in the collected solution. The mechanism of the reduction of Co3＋ to Co2＋ bearing minerals when SO2 is flushed during the leaching of mixed Co-Cu oxidized ores, including the stability trends of Co3＋, Co2＋, and Cu2＋ complexes, as shown by their UV/visible spectra, are also discussed.

关键词： cobalt metallurgy dissolution leaching reaction kinetics spectroscopic analysis

Influence of TiO_2 on the electrochemical performance of pasted typeβ-nickel hydroxide electrode in alkaline electrolyte

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journal of Energy Chemistry 2016年第1期25卷 41-48页

作者： b.Shruthi b.j.Madhu V.bheema Raju Department of Chemistry Dr. Ambedkar Institute of Technology Post Graduate Department of Physics Government Science College Department of Chemistry Dayananda Sagar College of Engineering

Nickel hydroxide was used as the positive electrode material in rechargeable alkaline batteries, which plays a significant role in the field of electric energy storage devices. β-nickel hydroxide（β-Ni（OH）2 ） was prepared from nickel sulphate solution using potassium hydroxide as a precipitating agent. Pure β-phase of nickel hydroxide was confirmed from XRD and FT-IR studies. The effects of TiO2 additive on the β-Ni（OH）2 electrode performance are examined. The structure and property of the TiO2 added β-Ni（OH）2 were characterized by XRD, TG-DTA and SEM analysis. A pasted–type electrode is prepared using nickel hydroxide powder as the main active material on a nickel sheet as a current collector. Cyclic voltammetry and electrochemical impedance spectroscopy studies were performed to evaluate the electrochemical performance of the β-Ni（OH）2 and TiO2 added β-Ni（OH）2 electrodes in 6 M KOH electrolyte. Anodic（Epa） and cathodic（Epc）peak potentials are found to decrease after the addition of TiO 2 into β-Ni（OH）2 electrode material. Further,addition of TiO2 is found to enhance the reversibility of the electrode reaction and also increase the separation of the oxidation current peak of the active material from the oxygen evolution current. Compared with pure β-Ni（OH）2 lectrode,TiO2 added β-Ni（OH）2 electrode is found to exhibit higher proton diffusion coefficient（D） and lower charge transfer resistance. These findings suggest that the TiO2 added β-Ni（OH）2 electrode possess improved electrochemical properties and thus can be recognized as a promising candidate for the battery electrode applications.

关键词： Nickel hydroxide Electrode material Thermogravimetric analysis Electrochemical properties Impedance spectroscopy