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defence Technology（防务技术） 2020年第6期16卷 1098-1105页

作者： Suhad d.Salman Mechanical Engineering department College of EngineeringMustansiriyah UniversityBaghdadIraq

due to notable characteristics,sustainability concept and environmental issues,hybridisation natural with synthetic fibres to fabricate composites have been rapidly gaining market share in different applications(structural,military,aerospace and automotive vehicles).Compression,tension and fatigue tests of various stacking sequences of plain jute/carbon reinforced(PVB)polyvinyl butyral by hot hydraulic press technique were experimentally *** types of fabricated composites with various constituents(jute,carbon and their hybrids)were fabricated and ***,fatigue lifetime of hybrids increases with increasing the carbon content relative to the jute fibre *** the other hand,Jute composites possess high strain compared to pure carbon composite,which gives an overall improvement in mechanical ***,H1 hybrid with Carbon/Jute/Carbon sequences offers similar fatigue stiffness behaviour of H3 hybrid with Carbon/Jute/Carbon/Jute sequences when subjected to cyclic *** composite(C)exhibited the highest fatigue resistance,whiles jute composite(J)possessed the highest strain and semi brittle trends in both mechanical and fatigue *** concluded that plain jute fibres could partially replace high-cost synthetic carbon fibres to produce more eco-friendly hybrids to be utilised in different composites industries.

关键词： Plain woven jute Carbon fabric Hybrid composite Mechanical Cyclic loading Morphological Fatigue properties

A Hybrid Joining Technology for Aluminum/Zinc Coated Steels in Vehicles

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Journal of Materials Science & Technology 2010年第9期26卷 858-864页

作者： C.Y.Choi d.C.Kim d.G.Nam Y.d.Kim Y.d.Park School of Materials Science and Engineering Pusan National UniversityBusan Advanced Welding & Joining R&d division Institute of Industrial Technology Incheon dongnam Technology Service division Korea Institute of Industrial TechnologyBusan department of Advanced Materials Engineering Dong-Eui UniversityBusan

Currently,in the automotive industry,joining of the aluminum alloys with the steel is a crucial problem to be *** joining techniques including resistance spot and gas metal arc welding are not acceptable for those applications due to a number of metallurgical *** investigation was carried out to develop the hybrid joining process combining the resistance spot welding and *** this study,an attempt was made to apply hybrid process to the joining of dissimilar sheet metals,Al-Mg-Si（6000 series） alloy and low carbon steel *** process（resistance spot weld/brazing） using filler metal was found to be effective to overcome the incompatibility between aluminum alloy and *** hybrid joining process of Al alloy sheet and steel sheet did not produce acceptable bond strength,it was proved to have reasonable interfacial bond layer if the optimal process condition was applied.

关键词： Hybrid joining Aluminum alloy Steel Resistance welding Brazing

Characteristics of urban ozone level in Hong kong

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Journal of Environmental Sciences 2001年第1期13卷 1-7页

作者： d.Y.C.LEUNG d.N.ZHANG department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina Research Institute of Environmental Engineering East China University of Science and TechnologyShanghai 200237China

The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contrary, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.

关键词： ozone urban air pollution Hong kong China

Advanced analytical determination of volatile organic compounds (VOC) and other major contaminants in water samples using GC-Ion Trap MS

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Journal of Environmental Sciences 2001年第1期13卷 25-36页

作者： B M Koroma K X Wang d d Jinya Laboratory of Socioeconomic Science of Food Production Nagoya University Japan.

The GC-Ion Trap MS is recently one of the most efficient instrumental analysis recommended for understanding the chemistry of volatile organic compounds, not only in water but even in the food chain and other environmental media (air and soil). Results of the experiment conducted on water samples from Kuguri and Yatsutani sampling stations showed considerably higher levels of organic enrichment (COd = 10 mg/L and 11 mg/L respectively). Total concentrations of Pb (0.072 mg/L and 0.093 mg/L) and Cd (0.004 mg/L and 0.011 mg/L) on the other hand, invariably exceeded the maximum allowable concentrations for human health and the living environment (Pb = 0.005 mg/L; Cd = 0.001 mg/L respectively). And the toxicity levels for these contaminants at LC50 showed critical impact on rainbow trout (hypersensitive species) at 0.14 mg/L for Pb and 0.007 mg/L for Cd in 96 hours respectively. Although these major contaminants including phenol and 3-, 4-cresol, showed relatively higher toxicity impact in the experimental media, it would remain contentious to justify any associated potential dangers without regular routine water monitoring, at least for a period of one year. Nevertheless, the data could serve as a benchmark through which other phenomena can easily be investigated.

关键词： www Advanced analytical determination of volatile organic compounds and other major contaminants in water samples using GC-Ion Trap MS VOC EB GC

Effectiveness of a fixed-depth sensor deployed from a buoy to estimate water-column cyanobacterial biomass depends on wind speed

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Journal of Environmental Sciences 2020年第7期32卷 23-29页

作者： Justin d.Chaffin douglas d.Kane Alex Johnson F.T Stone Laboratory and Ohio Sea Grant the Ohio State UniversityOH 43456USA division of Natural Science Applied Scienceand MathematicsDefiance CollegeDefiance OHF.T Stone LaboratoryThe Ohio State University and Ohio Sea GrantOH 43456USA

Water quality sondes have the advantage of containing multiple sensors,extended deployment times,high temporal resolution,and telecommunication with stakeholder accessible data ***,sondes that are part of buoy deployments often suffer from typically being fixed at one *** water treatment plants are interested in water quality at a depth of the water intake and other stakeholders(*** and swimmers)are interested in the surface,we examined whether a fixed depth of approximately 1 m could cause over-or under-estimation of cyanobacterial *** sampled the vertical distribution of cyanobacteria adjacent to a water quality sonde buoy in the western basin of Lake Erie during the summers of 2015–2017.A comparison of buoy cyanobacteria RFU(Relative Fluorescence Unit)at 1 m to cyanobacteria chlorophyll a(chla)measured throughout the water column showed occurrences when the buoy both under and overestimated the cyanobacteria chl a at specific *** differences between buoy measurements and at-depth grab samples occurred during low wind speeds(ds allowed cyanobacteria to accumulate at the surface above the buoy’s *** wind speeds(>4.5 m/sec)resulted in better agreement between the buoy and at-depth *** wind speeds 12 hr before sample collection decreased the difference between the buoy and at-depth samples for high wind speeds but not low *** suggest that sondes should be placed at a depth of interest for the appropriate stakeholder group or deploy sondes with the ability to sample at various depths.

关键词： Buoyancy Harmful algal bloom Lake Erie Microcystis Water quality

Release rate kinetics of corrosion inhibitor loaded halloysite nanotube-based anticorrosion coatings on magnesium alloy AZ91d

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Journal of Magnesium and Alloys 2021年第1期9卷 202-215页

作者： Swapnil H.Adsul Uday d.Bagale Shirish H.Sonawane R.Subasri Centre for Sol-Gel Coatings International Advanced Research Centre for Powder Metallurgy and New Materials(ARCI)BalapurHyderabad 500005Telangana StateIndia department of Food and Biotechnology South Ural State UniversityChelyabinsk 454080Russia department of Chemical Engineering National Institute of TechnologyWarangal 506004Telangana StateIndia

Halloysite nanotubes were used as nanocontainers to hold corrosion inhibitors such as Ce^(3+)-Zr^(4+),2-mercaptobenzothiazole and 8-hydroxyquinoline in their *** acid assisted etching of the nanotubes was carried out with a view to increase the lumen diameter and thereby,increase the amount of loading of the corrosion *** morphology of as-received and etched halloysite nanotubes was ob-served using TEM *** loading of corrosion inhibitors was confirmed using SEM-EdS and BET *** microcapsules were used as capping agents for the ends of the loaded HNTs following which,they were dispersed into a hybrid sol-gel silica *** coating method was used to generate coatings on AZ91d substrates followed by heat treatment at 130℃ for 1 *** release rate kinetics of corrosion inhibitors from as-received and etched nanotubes was investigated in buffer solutions of 3.5 wt%NaCl at different *** release mechanism of corrosion inhibitors from the HNT lumen was validated using various semi-empirical *** were also evaluated for their corrosion protection ability using electrochemical techniques after exposure to 3.5 wt%NaCl solution for 120 *** generated using Ce^(3+)-Zr^(4+)loaded into as-received halloysite nanotubes have shown more effective corrosion protection when compared to other corrosion inhibitors after 120 h exposure to the corrosive medium.

关键词： Sol-gel coating Halloysite nanotubes Corrosion inhibitors Release rate Magnesium alloy AZ91d

Luminescence properties of Gd^(3+) containing glasses for ultra-violet(UV) light

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Journal of Rare Earths 2014年第5期32卷 389-393页

作者： d.d.Ramteke R.S.Gedam department of Applied Physics Visvesvaraya National Institute of Technology

Effect of Gd2O3 addition on optical properties of 27.5 Li2O-72.5 B2O3 glass systems was studied. density, differential thermal analysis （dTA）, optical absorption spectra and luminescence technique were used to characterize the prepared glasses. Emis- sion spectra showed two band 6p7/2→8S7/2 （311.5 nm） and 6p5/2→8S7/2 （305 nm） under the excitation of 274 nm. The intense emission at 311.5 nm suggested that these glasses could be useful as source of narrowband UV light.

关键词： glasses rare earths absorption band gap luminescence UV light

Electrical and optical properties of lithium borate glasses doped with Nd_2O_3

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Journal of Rare Earths 2012年第8期30卷 785-789页

作者： R.S. Gedam d.d. Ramteke department of Applied Physics Visvesvaraya National Institute of Technology

Glass series with general formula 25Li2O-（75-x）B2O3-xNd2O3 was prepared by conventional melt quench technique. Electrical and optical characterizations of these glasses were carried out. It was observed that conductivity of glasses decreased and activation energy in- creased with the addition of Nd2O3. The density and refractive index of the glasses increased while optical band gap and radiation length de- creased due to structural changes.

关键词： conductivity density refractive index optical absorption Tauc's plot rare earths

Response of mollusk assemblages from the Luochuan loess section to orbital forcing since the last 250 ka

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Chinese Science Bulletin 2000年第17期45卷 1617-1622页

作者： d.d.Rousseau Laboratoire de Palynologie-URA 327 University Montpellier Ⅱ 34095 Montpellier France

This note presents a new result of terrestrial mollusk study from the Luochuan loesssection since the last 250 ka. A total of 213 samples, taken at intervals of 10 cm in the S0-L3 portion, were analyzed for fossil mollusks. Generally, 150-600 individuals were counted in each sample. According to the distribution of mollusk fossil assemblages in the loess section, 11 mollusk fossil zones have been recognized, representing different climatic and ecological conditions. Three main ecological groups were identified according to the temperature and moisture requirements of each taxon. The cold-aridiphilous group shows maxima at about 240-220, 190-182, 150-140 and 74 -66 ka BP. The thermo-humidiphilous set has high abundances for at least 6 times in the section at about 246-240, 220-216, 170-158, 92-86, 60-44 and 10 kaBP. Our results show that variations in mollusk ecological groups are related with changes in the Earth orbital parameters at the 41 and 20 ka frequencies. Maxima in thermo-humidiphilous taxa

关键词： mollusk assemblage loess orbital forcing.

Structure and Properties of Chemically-reduced Functionalized Graphene Oxide Platelets

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Journal of Materials Science & Technology 2015年第5期31卷 458-462页

作者： A.Pruna d.Pullini d.Busquets University of Bucharest 405 Atomistilor Str077125 Bucharest-MagureleRomania Institute of Materials Technology University Politecnica of ValenciaCamino de Vera s/n46022 ValenciaSpain Fiat Research Centre

Green reduction of graphene oxide(GO) functionalized with 3-aminopropyltriethoxysilane and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide was performed by using ascorbic acid and sodium *** obtained materials were characterized by thermo-gravimetric analysis,transmission electron microscopy.X-ray diffraction,UV-Vis,Fourier transform infrared and Raman spectroscopy *** results indicated a strong dependence of the materials properties such as deoxygenation degree,absorption peak shift,crystallite size and functionalization degree on the functionalization approach and reducing agent.

关键词： Covalent functionalization Graphene oxide Reductio