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Structure and Properties of Nanostructured vacuum-Deposited Foils of Invar Fe–(35–38 wt%)Ni Alloys

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Journal of Materials Science & Technology 2015年第11期31卷 1079-1086页

作者： v.M.Nadutov A.I.Ustinov S.A.Demchenkov Ye.o.Svystunov v.S.Skorodzievski G.v.Kurdyumov Institute for Metal Physics of National Academy of Sciences of Ukraine E.o.Paton Electric Welding Institute of National Academy of Sciences of Ukraine

The process of electron beam vacuum deposition of the Fe-（35-38 wt%）Ni alloys at substrate temperatures Ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size of characteristic microstructural elements （grains and subgrains）. It was shown that refinement of foil microstructural elements to nanoscale is accompanied by their microhardness increase up to 4-5 GPa. The change of the thermal expansion coefficient （TEC） of the nanostructured （NS） foil of the Fe-35.1Ni alloy within the temperature range from -50 to 150 ℃ has some deviation from that observed for cast Invar alloy of the same composition. It has been found that the main factors affecting the peculiarities of thermal expansion of the NS foil can be related to the presence of small fraction of BCC- phase in them, high level of crystalline lattice microstrains and inhomogeneous magnetic order in FCC- phase. It was shown that as a result of additional thermal treatment of NS foils their invar properties become similar to that observed for cast Invar alloy but mechanical properties remain on the same level.

关键词： Fe-Ni alloys Electron beam physical vapor deposition (EBPvD) Nanostructured materials Hardness Thermal expansion Mossbauer spectroscopy

Assessment of two persistent bioaccumulative toxicants in the UNESCo protected river of osun-osogbo, Nigeria

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Ecological Processes 2017年第1期6卷 323-330页

作者： Emmanuel o.Akindele Godwin o.olutona oyeshina G.oyeku Akinkunle v.Adeniyi Department of Zoology Obafemi Awolowo UniversityIle-IfeNigeria Department of Chemistry and Industrial Chemistry Bowen UniversityIwoNigeria Department of Biological Sciences Bowen UniversityIwoNigeria Institute of Ecology and Environmental Studies Obafemi Awolowo UniversityIle-IfeNigeria

Introduction:osun River dissecting the osun-osogbo Sacred Grove,though inscribed on the World Heritage List,has been rarely assessed for biodiversity values or *** this study,we investigated the concentrations of Cu and Zn in the benthic sediments and two dominant gastropod species(Melanoides tuberculata and Lanistes varicus)of the osun *** sediment and gastropod samples were collected on quarterly basis from June 2015 to March 2016 along the longitudinal stretch of the *** samples were digested and analysed for Cu and Zn using the atomic absorption ***:With the exception of September sampling period,the two metals recorded higher values in the animals than in the ***(1.23±0.81μg/g)was much lower(pvein,Cu was significantly lower(poth *** metals recorded much lower values than their average concentrations in the Earth’s crust as well as the recommended limits for freshwater ***,*** recorded higher bioaccumulation factor than ***:Findings from this study suggest that both metals posed no toxicological risk to the freshwater system of osun *** of both metals in the sediments as well as their accumulation factors in both gastropod species were indicative of an unimpacted freshwater system.

关键词： :Accumulation Benthic sediments Contamination Ecotoxicology Heavy metals Freshwater gastropods

Study of Sorption Properties of Anion Exchangers with Long-Chained Cross-Linking Agents for Tungsten Hydrometallurgy

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Chinese Journal of Chemical Engineering 2000年第3期8卷 241-246页

作者： A.G.Kholmogorov o.N.Kononova S.v.Kachin o.P.Kalyakina G.L.Pashkov Institute of Chemistry and Chemical Technology Siberian Department fo Academy of ScienceKarl Marx Pr.42660049 KrasnoyarskRussia Department of Chemistry KrasnoyarskState UniversitySvobodny Pr.79660062 KrasnoyarskRussia

The macroporous anion exchangers with long-chained cross-linking agents were investigated for the tungsten recovery from salt *** physical-chemical characteristics of these sorbents were studied by means of sorption-desorption experiment aswell as electron and *** anion exchangers on the basis of macroporous copolymers of methylacrylate and divinyl-ester of diethyleneglycol or tetravinyl-ester of pentaerythritol possess the exchange capacity to tungsten 2--5 times greater than the porous anion exchangers on the basis of styrene and divinylbenzene,therefore they can be used for selective tungsten recovery from comulex salt solutions.

关键词： anion exchangers macroporous structure long-chained cross-linking agents tungsten recovery salt solution

Methane oxidative carbonylation catalyzed by rhodium chalcogen halides over carbon supports

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Journal of Natural Gas Chemistry 2008年第1期17卷 1-7页

作者： G.R.Kosmambetoval P.E.Strizhak v.I.Gritsenko S.v.volkov L.B.Kharkova o.G.Yanko o.M.Korduban L.v Pisarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine pr.Nauki 31Kiev03039Ukraine v.I.vernadsky Institute of General and Inorganic Chemistry of National Academy of Sciences of Ukraine pr.PaUadina 32/34Kiev03680Ukraine v.I.vernadsky Institute of General and Inorganic Chemistry of National Academy of Sciences of Ukraine pr.Palladina 32/34Kiev03680Ukraine G.v.Kurdyumov Institute of Metal Physics of National Academy of Sciences of Ukraine 36Vernadskij avKyiv03680Ukraine

Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carbon supports. XPS and IR-spectroscopy data show the formation of rhodium chalcogen halides in solids prepared by different methods. We have found that the productivity of acetic acid by carbon supported rhodium chalcogen halides depends strongly on the carbon carrier and the method of the catalyst preparation. Namely, the catalyst with highest productivity for the acetic acid is prepared by synthesizing the rhodium chalcogen halide over the carbon support followed by thermal destruction. We have also found that rhodium chalcogen halides over activated carbons are more active compared with fullerene supported catalysts.

关键词： catalysts methane oxidative carbonylation rhodium chalcogen halides carbon supports

Coercivity kinetics upon step annealing of sintered Sm(Co0.88-xFexCu0.09Zr0.03)7 magnets

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Journal of Rare Earths 2019年第10期37卷 1059-1065页

作者： A.G.Popov o.A.Golovnia A.v.Protasov v.S.Gaviko D.A.Kolodkin R.Gopalan M.N.Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences Str.S.Kovalevskoy18Ekaterinburg620990Russia Institute of Natural Sciences and Mathematics Ural Federal Universitypr.MiraEkaterinburg19620002Russia International Advanced Research Centre for Powder Metallurgy and New Materials(ARCI) IITM Research ParkChennai 600113India

Behavior of the coercivity of the high-temperature Sm(Co0.88-xFexCu0.09Zr0.03)7 magnets depending on the temperature and time of annealing with the temperature decreasing stepwise from 700 to 400℃ was *** is shown that the growth rate of coercivity abruptly increases at the initial stage of annealing in the vicinity of the Curie temperature of the SmCo5 *** origin of the effect is the counter diffusion of Cu and Co atoms through dislocation tubes,which form because of enhanced stresses and a partial breakage of coherent coupling at the interface of the Sm2 Co17 and SmCo5 *** enrichment of the SmCo5 phase in Cu close to the interface with Sm2 Co17 leads to relaxation of stresses and increases in the gradient of the magnetic domain-wall energy and coercivity.

关键词： Sm-Co-Fe-Cu-Zr Permanent magnet Sm2Co17 SmCo5 Coercivity kinetics

Comparative carbon emission assessments of recycled and natural aggregate concrete: Environmental influence of cement content

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Geoscience Frontiers 2021年第6期12卷 66-75页

作者： Marian Sabǎu Dan v.Bompa Luis F.o.Silva Department of Civil and Environmental Engineering Universidad de la Costa080020 BarranquillaColombia Department of Civil and Environmental Engineering University of SurreyGuildford GU27XHUK Departamento de Ingeniería Civil y Arquitectura Universidad de LimaAvenida Javier Prado Este 4600Santiago de Surco 1503Peru

This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural *** environmental influence of cement content,aggregate production,transportation,and waste landfilling is analysed by undertaking a life cycle assessment and considering a life cycle inventory largely specific for the *** obtain a detailed insight into the optimum life cycle parameters,a sensitivity study is carried out in which supplementary cementitious materials,different values of natural-to-recycled aggregate content ratio and case-specific transportation distances were *** results show that carbon emissions were between 323 and 332 kgCo_(2)e per cubic metre of cement only natural aggregate *** values can be reduced by up to 17%by replacing 25%of the cement with fly *** contrast,carbon emissions can increase when natural coarse aggregates are replaced by recycled aggregates in proportions of 50%and 100%,and transportation is not included in ***,the concrete with 50%recycled aggregate presented lower increase,only 0.3%and 3.4%for normal and high strength concrete,*** some cases,the relative contribution of transportation to the total carbon emissions increased when cement was replaced by fly ash in proportions of 25%,and case-specific transportation distances were *** absolute values,the concrete mixes with 100%recycled aggregates and 25%fly ash had lower carbon emissions than concrete with cement and natural aggregates *** environmental benefits can be obtained when the transportation distances of fly ash are relatively short(15–25 km)and the cement replacement by fly ash is equal or higher than 25%,considering that the mechanical properties are adequate for practical *** observations from this paper show that recycled aggregate concrete with strength characteristics representative for structural members can have lowe

关键词： Life cycle assessment Recycled aggregate Natural aggregate Transportation distance openLCA

Cross-sections for the 27Al(γ,x)22Na multichannel reaction with the 28.3 Mev difference of reaction thresholds

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Chinese Physics C 2022年第6期46卷 129-137页

作者： o.S.Deiev I.S.Timchenko S.N.olejnik v.A.Kushnir v.v.Mytrochenko S.A.Perezhogin National Science Center"Kharkov Institute of Physics and Technology" 1 Akademichna St.61108 KharkivUkraine

The bremsstrahlung flux-averaged cross-sections(σ(Eγmax))and the cross-sections per equivalent photon(σ(Eγmax)Q)were first measured for the photonuclear multichannel reaction ^(27)Al(γ,x)22 Na at end-point bremsstrahlung gamma energies ranging from 35 Mev to 95 *** experiments were performed with the beam from the NSC KIPT electron linear accelerator LUE-40 using theγ-activation *** bremsstrahlung quantum flux was calculated with the GEANT4.9.2 program and was also monitored via the ^(100)Mo(γ,n)^(99)Mo *** flux-averaged cross-sections were calculated using the partial cross-sectionσ(E)values computed with the TALYS1.95 code for different level density *** is given to special features of calculating the cross-sectionsandfor the case of the final nucleus ^(22)Na via several partial channels x:nα+dt+npt+2 n^(3) He+n2d+2 npd+2 p3 n.

关键词： bremsstrahlung flux-averaged cross-section bremsstrahlung end-point energy of 35-95 Mev activation and off-lineγ-ray spectrometric technique TALYS1.95 GEANT4.9.2

Isomeric ratio of the ^(181)Ta(γ,3n)^(178m,g)Ta reaction products at energy Eγmax up to 95 Mev

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Chinese Physics C 2022年第1期46卷 102-109页

作者： o.S.Deiev I.S.Timchenko S.N.olejnik v.A.Kushnir v.v.Mytrochenko S.A.Perezhogin National Science Center"Kharkiv Institute of Physics and Technology" 1 Akademicheskaya St.61108 KharkivUkraine

The photoneutron reaction^(18)Ta(y,3m)(178m,g)Ta was investigated with the beam from the NSC KIPT electron linear accelerator *** measurements were performed using the residual y-activity *** bremsstrahlung flux-averaged cross sections((E_(γmax))>.(r(E_(γmax))>m.omerie ratio of the re-action products d(E_(γmax))were *** theoretical values of the averaged cross-sections and isomeric ratio were calculated using the partial cross-sections from the TALYS1.95 code for different level density models LD 1-6..The obtained experimental d(E_(γmax))agree with the data in the lterature,but differ from the theoretical values in ab-solute magnitude and the behavior of the energy dependence.A comparison of the determined averaged cross-sec-tions with the calculated cross sections showed the best agreement for the case of the LD 5 model.

关键词： bremsstrahlung flux-averaged cross-section isomeric ratio bremsstrahlung end-point energy of 35-95 Mev activation and off-line 7-ray spectrometric technique TALYS1.95 GEANT4.9.2

Magnetic Behaviour of Tb/Si Nanoscale Multilayers with Small Thickness of Rare Earth Layers

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Chinese Physics Letters 2007年第6期24卷 1717-1719页

作者： A.v. Svalov v.o. vas'kovskiy G.v. Kurlyandskaya J.M. Barandiaran N.N. Schegoleva A.N. Sorokin Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Universidad del Pals vasco UPv-EHU Facultad de Ciencias Depto Electricidad yVElectr6nica Apdo. 644'48080 Bilbao Spain Institute of Metal Physics Ural Branch of RAS Kovalevskaya str. 18 620219 Ekaterinburg Russia

We report the magnetic properties of Tb/Si multilayers obtained by rf-sputtering at the Tb layer thickness LTb = 3 nm. Analysis of the magnetization processes indicates more complex behaviour than canonical spinglass transition. It is more probable that these multilayers contain both Tb superparamagnetic particles and Tb-Si spin-glass alloys.

关键词： SPIN-GLASS TRANSITIoN GD/W MULTILAYERS TERBIUM FILMS NANoPARTICLES