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Defence Technology（防务技术） 2018年第5期14卷 396-402页

作者： A.A.Daniyan L.e.Umoru O.S.i.Fayomi A.P.i.Popoola Department of Materials Science and engineering Obafemi Awolowo University Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology Department of Mechanical engineering Covenant University

Multifunctional nano composite coatings of Zn-TiO_2-WO_3 were deposited electrolytically on mild steel(MS) from Zn bath, having Zn^(2+) ions and uniform dispersion of TiO_2 and WO_3 nano particulates. The electrical, optical and corrosion resistance characteristics of the electrocodeposited coatings were assessed by Keithley 2400 Series Source meter with Multimeters, Newport Solar Simulator and a PGSTAT30 Autolab potentiostat respectively. The morphological characteristics of the composite coatings were characterized by scanning electron microscope(SeM) equipped with energy dispersive spectrometer(eDS). The result revealed that the electrocodeposits showed good stability and Zn-TiO_2-WO_3 nanocomposite deposits displayed enhanced microstructural qualities, good electrical conductivity and exhibited enriched corrosion resistance.

关键词： Nano-composite electrocodeposition Corrosion Conductivity and resistance

Groundwater occurrence and flow patterns in the ishiagu mining area of southeastern Nigeria

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Frontiers of earth Science 2012年第1期6卷 18-28页

作者： i.C.eZeKWe e.ODUBO G.N.CHiMA i.S.ONWUCHeKWA Department of Geography and environmental Management Niger Delta UniversityWilberforce IslandPMB 071YeneganaNigeria Department of Geography and Planning Abia State UniversityPMB 2000UtumNigeria

The ishiagu area is a water scarce region and has played host to mining activities for more than four decades. Mining-related activities have become a threat to potable water supply in the area. This paper is an attempt to show the extent of this threat and in particular, investigate the regional groundwater occurrence and flow pattem based on GPS, water well and geological data. This basin- wide model can be used for further groundwater assess- ment, pollution control and contaminant management. Groundwater occurs between 2.4 and 9 m in the Lekwesi- Lokpaukwu area; 1.5-3.7 m in the Ndi-Ugbugbor-Ayaragu axis and 1.2-4.6 m in the ishiagu area. Recharge areas include the Leru-Amaubiri-Lekwesi sandstone hills and the ihetutu-Ugwuajirija mine field. While the ultimate sink of contamiants is the ivo River system, other discharge axis is the ishiagu-Ayaragu axis and the Ogwor Ndi- Ugbugbor zone. An unconfined and a confined （〉 10） circulation groundwater system was inferred, and flow model reveals that a large part of ishiag-Ayaragu and Ndi- Ugbugbor part of the study area suffer polluted recharge from the Pb/Zn mining area. Groundwater was also subjected to hierarchical cluster analysis and the existence of 3-4 hydrological regimes, which revealed： Unpolluted recharge areas, areas affected by polluted recharge, a deep water and shallow water circulation and mine effluents.

关键词： groundwater flow mining heavy metals,pollution cluster analysis ishiagu Nigeria

Systematic experimental study of the temperature dependence of viscosity and rheological behavior of water-based drilling fluids with nano-additives

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Petroleum 2023年第4期9卷 534-544页

作者： A.V.Minakov M.i.Pryazhnikov e.i.Mikhienkova Y.O.Voronenkova Siberian Federal University KrasnoyarskRussia Kutateladze institute of Thermophysics SB RASNovosibirskRussia

The paper presents the results of a systematic study of the influence of nano-additives of various concentrations,average sizes and composition on the temperature dependence of the viscosity and rheological behavior of water-based drilling *** compositions of drilling fluids,such as water suspensions of various clay solutions and gammaxan-based polymer solutions,were *** nanoparticles of silicon and aluminum oxides were used as nano-additives at concentrations ranging from 0.25 to 3 wt%.The average nanoparticle size varied from 10 to 151 *** temperature of drilling fluids varied from 25℃ to 80℃.it is shown that the addition of nanoparticles to drilling fluids leads to a significant change in their rheological properties depending on the *** was found that with increasing temperature,the yield stress and consistency index of drilling fluids with nanoparticles increase,while the behavior index,on the contrary,*** behavior depends on the size of the *** the particle size increases,their influence on the temperature dependence of the drilling fluids’viscosity *** general,it is shown that the addition of nanoparticles makes the viscosity of drilling fluid more stable with regard to the *** is an essential fact for practical application.

关键词： Drilling fluid Nano-additive Viscosity Rheology Temperature

electron-phonon coupling and spin fluctuations in the ising superconductor NbSe_(2)

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npj Computational Materials 2023年第1期9卷 1686-1694页

作者： S.Das H.Paudyal e.R.Margine D.F.Agterberg i.i.Mazin Department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Quantum Science and engineering Center George Mason UniversityFairfaxVA 22030USA Department of Physics Applied Physicsand AstronomyBinghamton University-SUNYBinghamtonNY 13902USA Department of Physics University of WisconsinMilwaukeeWI 53201USA

ising superconductivity,observed in NbSe2 and similar materials,has generated tremendous ***,attention was called to the possible role that spin fluctuations(SF)play in this phenomenon,in addition to the dominant electron–phonon coupling(ePC);the possibility of a predominantly triplet state was discussed and led to a conjecture of viable singlet–triplet Leggett ***,these hypotheses have not been put to a quantitative *** this paper,we report first principle calculations of the ePC and also estimate coupling with SF,including full momentum *** find that:(1)ePC is strongly anisotropic,largely coming from the K-K0 scattering,and therefore excludes triplet symmetry even as an excited state;(2)superconductivity is substantially weakened by SF,but anisotropy remains as above;and,(3)we do find the possibility of a Leggett mode,not in a singlet–triplet but in an s_(++)–s_(±)channel.

关键词： coupling phonon superconductivity

Nano-enhanced Dairy Scum Biodiesel Blends:Unleashing the Power of Aluminium Oxide for Sustainable and efficient engine Performance

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Journal of Thermal Science 2025年第1期 283-302页

作者： Veeranna MODi Prasad B.RAMPURe Sunil Kumar SHeTTY Madeva NAGARAL Channa Keshava NAiK N Johar MGM Muhammad irsyad ABDULLAH Abdullah i.AL-MANSOUR Shamshad ALAM KLe College of engineering and Technology ChikodiVisvesvaraya Technological University Nitte (Deemed to be University) NMAM Institute of Technology (NMAMIT)Department of Mechanical Engineering Aircraft Research and Design Centre HAL Department of Mechanical engineering BGS College of Engineering and TechnologyBengaluruAffiliated to Visvesvaraya Technological University Management and Science University Department of Civil engineering College of EngineeringKing Saud University

This study investigates the effect of aluminium oxide nanoparticlesaddition to biodiesel blends made from dairy milk scum on performance and combustion characteristics of the diesel *** dispersion of Al2O3nanoparticles in B20 blends at different concentrations was done with the help of *** number of blends were prepared for the *** Machine learning algorithms(Random Forest（RF）and CatBoost) was used for the *** results show that in comparison to biodiesel blends without nanoparticles,the kinematic viscosity and density is higher for fuel blends with *** these Fuel blends have higher calorific *** blends exhibited reduced Brake Specific Fuel Consumption（BSFC） of2.85% than the blends without nano particles(Dairy Scum Methyl ester Biodiesel 20%+Neat Diesel 80%（in volume）,DSMeB20),57.14% less CO,40.8% less hydrocarbon,and increased NOxemissions compared to conventional diesel,contributing to the development of environmentally friendly and renewable biofuel blends with *** B20NP30 is the optimal blend for performance and emission *** study concludes with findings on enhanced Brake Thermal efficiency（BTe） of 26.29% in 3×10-5（in volume） Al2O3nanoparticle-blended DSMe B20 and other DSMe B20 fuel blends,emphasizing the importance of optimal nanoparticle *** correlation matrix shows how engine load,efficiency measures（BTe,BSFC）,and emissions（CO,CO2,NOx,Smoke） are connected in complex *** results help us understand the complicated dynamics of engine performance and emission characteristics ***'s diagram for BTe and BSFC shows that CatBoost-based BTe models perform superior to RF-based models during the training as well as testing *** results were obtained for CO and CO2emission results.

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Photoluminescence properties of eu3+-doped MgAl2O4 nanoparticles in various surrounding media

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Journal of Rare earths 2019年第8期37卷 806-811,I0001页

作者： i.e.Kolesnikov e.V.Golyeva e.V.Borisov e.Yu Kolesnikov e.Lahderanta A.V.Kurochkin M.D.Mikhailov St.Petersburg State University St.PetersburgRussia Lappeenranta University of Technology LUT LappeenrantaFinland Peter the Great St.Petersburg Polytechnic University St.PetersburgRussia Scientific and Technological institute of Optical Material Science VNTs S.I.Vavilov State Optical InstituteSt.PetersburgRussia Volga State University of Technology Yoshkar-OlaRussia

eu3+-doped MgAl2O4 nanoparticles were prepared by modified Pechini method.X-ray diffraction analysis shows pure tetragonal spinel phase without any *** average size of synthesized nanoparticles was determined to be about 50-60 nm using scanning electron microscopy and static light scattering *** and excitation spectra as well as lifetimes of MgAl2O4:eu3+ nanophosphors were explored in surrounding media with different refractive *** medium does not affect luminescence bands position,whereas 5D0 lifetime monotonically decreases along with increase of medium refractive *** of surrounding media on radiative and nonradiative decay rates,which were calculated using 4f-4f intensity theory,was studied and *** factor of prepared nanoparticles is defined using both radiative and observed lifetimes.

关键词： eu3+ Nanoparticles Filling factor Luminescence Lifetime Rare earths

From blood to breath: New horizons for esophageal cancer biomarkers

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World Journal of Gastroenterology 2016年第46期22卷 10077-10083页

作者： Roger Yazbeck Simone e Jaenisch David i Watson Department of Surgery Flinders Centre for Innovation in Cancer Flinders University

esophageal cancer is a lethal cancer encompassing adenocarcinoma and squamous cell carcinoma subtypes. The global incidence of esophageal cancer is increasing world-wide, associated with the increased prevalence of associated risk factors. The asymptomatic nature of disease often leads to late diagnosis and five-year survival rates of less than 15%. Current diagnostic tools are restricted to invasive and costly endoscopy and biopsy for histopathology. Minimally and non-invasive biomarkers of esophageal cancer are needed to facilitate earlier detection and better clinical management of patients. This paper summarises recent insights into the development and clinical validation of esophageal cancer biomarkers, focussing on circulating markers in the blood, and the emerging area of breath and odorant biomarkers.

关键词： Breath analysis Cancer Micro RNA Noninvasive esophageal cancer Biomarker

High-Strength Nanostructured Cold-Resistant Steels for Continental Shelf Development

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Journal of iron and Steel Research international 2011年第S1期18卷 66-71页

作者： Oryshchenko A S Khlusova e i Orlov V V FSUe CRiSM PROMeTeY St.PetersburgRussia

The article describes principles of developing steels for maritime structures and main *** scientific approach lies in forming an ultra fine-grained and submicrocrystal structure through thermomechanical treatment of low-carbon low-alloyed steels,providing higher strength and resistance to brittle *** article presents results of assessing the operability characteristics and introducing new steels.

关键词： low-alloyed steels microstructure mechanical properties thermomechanical treatment

Audio-frequency heating of particulate magnetic systems

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China Particuology 2007年第1期5卷 84-92页

作者： B.e. Kashevsky i.V. Prokhorov S.B. Kashevsky A.V. Luikov Heat and Mass Transfer institute Belarus Academy of Sciences P. Brovka str. 15 Minsk 220072 Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy dissipation in suspensions of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. energy absorption by particles suspended in a solid, liquid or gas environment and subjected to high frequency magnetic fields is of great interest for cancer treatment by hyperthermia, chemical technology, biotechnology and smart materials science. Sub-micron needle-like γ-Fe2O3 particles dispersed in liquid were subjected in this study to a 430 Hz magnetic field with an intensity of up to 10^5 A/m. Dynamic magnetization loops were measured in parallel to the energy dissipated in the samples. Combined magnetomechanical dynamics of particle dispersions was simulated by using a chain-of-spheres model allowing for incoherent magnetic field reversal. in liquid dispersions, within the kilohertz frequency range, the mechanical mobility of particles does not interfere with their hysteretic magnetic reversal that makes heat release comparable to that observed with solids; for instance, in the present study using γ-Fe2O3 particles in liquid subjected to 10^4 Hz field exhibited heat release rates from 250 up to 600W oer 1 cm^3 of the dry oarticle content.

关键词： AC magnetic field Particulate materials Audio-frequency heating

effects of manganese doping on magnetocaloric effect in Ge-rich Gd_5Ge_(2.05)Si_(1.95) alloy

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Journal of Rare earths 2012年第3期30卷 217-221页

作者： e.Yüzüak i.Dincer Y.elerman Department of engineering Physics Faculty of EngineeringAnkara University

The structure, magnetic and magnetocaloric properties of the Ge-rich Gd5Ge2.05-xSi1.95-xMn2x （x=0.01 and 0.03） alloys were investigated by scanning electron microscopy, X-ray powder diffraction, differential scanning calorimeter （DSC） and magnetization measurements. The results of energy dispersive X-ray analysis （eDX） and X-ray diffraction analyses showed that the composition and crystal structure of the alloys were desired. DSC measurements were performed to determine the transformation temperatures for each alloy. Both alloys exhibited the first order phase transition around room temperature. The alloys showed an anti-ferromagnetic transition around 60 K. The isothermal magnetic entropy changes of the alloys were determined from the isothermal magnetization measurements by using the Maxwell relation. The maximum values of isothermal magnetic entropy change of the Gd5Ge2.05-xSi1.95-xMn2x alloy with x=0.01 was found to be -12.1 and -19.8 J/（kg·K） using Maxwell equation around 268 K in applied fields of 2 and 5 T, respectively.

关键词： magnetocaloric effect entropy change magnetic materials rare earths