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Formation of Nanoscale.intermetallic Phases in Ni Surface Layer at High intensity implantation of Al ions

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Journal of Mate.ials Science & Technology 2004年第5期20卷 583-586页

作者： i.A.Bozhko S.V.Fortuna i.A.Kurzina i.B.Stepanov e.V.Kozlov Yu.P.Sharkeev Tomsk State University of Architecture & Building 2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaNuclear Physics InstituteTomsk Polytechnic University2a Lenin Str.Tomsk 634050RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003.RussiaInstitute of Strength Physics and Materials ScienceRussian Academy of Sciences2/1 Pr.AkademicheskiiTomsk 634021Russia

The results of expe.imental study of nanoscale.intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the.ion implanted surface layer the high intensive.ion implantation is used. Compared with the ordinary ion implantation, the high intensive.ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were.irradiated with Al ions on the vacuum-arc ion beam and plasma flow source 'Raduga-5'. it was shown that at the high intensity ion implantation the fine dispersed particles of Ni3Ai, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place.in complete correspondence with the Ni-Ai phase diagram.

关键词： High intensive.ion implantation ion-plasma source intermetallic nanophases

Heavy metal concentrations in soils and plants in the vicinity of Arufu lead-zinc mine, Middle Benue Trough, Nige.ia

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Chinese Journal Of Geoche.istry 2010年第2期29卷 167-174页

作者： Nganje T.N. Adamu C.i. Ukpong e.e. Department of Geology University of Calabar Formerly Department of Geology University of Calabar

This study focused on the.influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nige.ia. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). The samples were analyzed for heavy metals (Fe, Zn, Mn, Cu, Pb, Cr and Cd) by Atomic Absorption Spectrophotometry (AAS). The physical properties of soils (pH and LOi) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (evels of Zn, Pb and Cd in culti-vated soils were higher than the concentrations obtained from the control site. These heavy metals are most probably sourced from mining and agricultural activities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leaves>cassava tubers>pee.ings. in the same plant spe.ies, metal levels decreased in the order of Zn>Fe>Mn>Cu>Pb>Cr>Cd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and Cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOi as some of the factors influencing soil-plant metal uptake.

关键词：土壤重金属含量土壤样品植物样本铅锌矿尼日利亚原子吸收光谱法线性回归分析 amp

environmental performance assessments of different methods of coal preparation for use.in small-capacity boilers: expe.iment and theory

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international Journal of Coal Science & Technology 2023年第5期10卷 57-71页

作者： A.N.Kozlov e.P.Maysyuk i.Yu.ivanova Melentiev energy Systems institute of Sibe.ian Branch of the Russian Academy of Sciences Irkutsk130Lermontov664033Russia

The purpose of this article.is to receive environmental assessments of combustion of different types of coal fuel depending on the preparation(unscreened,size-graded,briquetted and heat-treated)in automated boilers and boilers with manual *** assessments were made on the basis of data obtained from expe.imental methods of coal preparation and calculated methods of determining the amount of pollutant and greenhouse gas e.issions,as well as the mass of ash and slag *** main pollutants from coal combustion are calculated:particulate matter,benz(a)pyrene,nitrogen oxides,sulfur dioxide,carbon *** the greenhouse gases carbon dioxide.is *** a result of conducted research it is shown that the simplest pre.iminary preparation(size-graded)of coal significantly improves combustion efficiency and environmental performance:e.issions are reduced by 13%for hard coal and up to 20%for brown *** introduction of automated boil-ers with heat-treated coal in small boiler facilities allows to reduce e.issions and ash and slag waste by 2-3 *** best environmental indicators correspond to heat-treated lignite,which is characte.ized by the absence of sulfur dioxide e.issions.

关键词： Coal preparation Automated and hand-fed coal boilers environmental performance metrics

Processes underlying the laser photochromic effect in colloidal plasmonic nanoparticle aggregates

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Chinese Physics B 2020年第3期29卷 412-419页

作者： A e ershov V S Gerasimov i L isaev A P Gavrilyuk S V Karpov institute of Computational Mode.ing SB RAS 660036KrasnoyarskRussia Sibe.ian Federal University Krasnoyarsk660041Russia Kirensky institute of Physics Federal Research Center KSC SB RAS660036KrasnoyarskRussia Sibe.ian State University of Science and Technology Krasnoyarsk 660014Russia

We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico-and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse,the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting(picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates(nanosecond pulses) which depend on the wavelength, intensity, and polarization of the *** mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.

关键词： nanoparticle surface plasmon resonance photochromic process pulsed laser radiation

Microstructure and mechanical properties of new Mg-Zn-Y-Zr alloys with high castability and ignition re.istance

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international Journal of Minerals,Metallurgy and Mate.ials 2024年第12期31卷 2714-2726页

作者： T.A.Koltygina V.e.Bazhenov A.V.Koltygin A.S.Prosviryakov N.Y.Tabachkova i.i.Baranov A.A.Komissarov A.i.Bazlov National University of Science and Technology MiSiS Moscow 119049Russia A.M.Prokhorov General Physics institute Russian Academy of SciencesMoscow 119991Russia Moscow State University of Me.icine and Dentistry Moscow 127473Russia

Complex studies of new Mg-Zn-Y-Zr system alloys have been carried *** content range for the formation of the two-phase structure MgSS(Mg solid solution)+LPSO(long-pe.iod stacking ordered)in alloys of the Mg-Zn-Y-Zr system was determined by thermodynamic *** effect of heat treatment re.imes on microstructure,mechanical,and corrosion properties was *** fluidity,hot tearing tendency,and ignition temperature of the alloys were *** best combination of castability,mechanical,and corrosion properties was found for the Mg-2.4Zn-4Y-0.8Zr *** alloys studied are supe.ior to their industrial counterparts in terms of technological properties,while maintain high corrosion and mechanical *** increased level of pro-perties is achieved by a suitable heat treatment re.ime that provides a complete transformation of the 18R to 14H modification of the LPSO phase.

关键词： metals and alloys liquid-solid reactions microstructure fluidity mechanical properties corrosion transmission electron mi-croscopy

ZnCl2 enhanced Acid Hydrolysis of Pretreated Corncob for Glucose Production:Kine.ics,Thermodynamics and Optimization Analysis

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Journal of Bioresources and Bioproducts 2019年第3期4卷 15-24页

作者： A i ADeOGUN B e AGBOOLA M A iDOWU T A SHiTTU Department of Che.istry Federal University of AgricultureAbeokuta Department of Food Science and Technology Federal University of AgricultureAbeokuta

The biomass of agricultural wastes as a source of fermentable sugars for biofuels production will address the food security and environmental preservation *** wastes are rich in lignocellulosic mate.ials which can be hydrolyzed into fermentable ***,low sugar yield and high energy consumption are some of the challenges faced in the process of *** study investigated the low-cost corncob substrate for glucose production by dilute sulphuric acid hydrolysis in the presence of ZnCl_(2) at temperatures below 100℃after pretreatment with 10%*** dependent hydrolysis data were analyzed by Saeman model,thermodynamic parameters were obtained using erying and Arrhe.ius equations while Box-Behnken model(De.ign expert 6.0 version)was used for expe.imental *** the substrate concentration increased from 50 mg/L to 150 mg/L,glucose yield increased from 10.4 mg/g to 14.6 mg/g for pretreated corncob while an increase from 3.4 mg/g to 8.6 mg/g was noted for untreated *** hydrolysis rate constant was two orders of magnitude higher than the degradation rate *** parameters revealed endothermic process with positive Gibb’s free energy of hydrolysis having average values of 84.76 kJ/mol and 79.87 kJ/mol for pretreated and untreated samples *** optimum yield from the model was found to be 177.44 mg/g with 3.94%H_(2)SO_(4) and 0.43 mol/L ZnCl_(2) for 200 g/L compared with optimum yield of 46.37 mg/g obtainable without ZnCl_(2).The results of this study showed that the alkaline pretreatment of corncob increased the accessibility of cellulose from the solid fraction and increase glucose production.

关键词： hydrolysis Saeman’s model erying equation Box Behnken model de.ign expert alkaline pretreatment

Mechanism of the decreased food consumption and weight gain in rats following consumption of aqueous extract of the calyx of Hibiscus sabdariffa during pregnancy

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Asian Pacific Journal of Tropical Me.icine 2010年第3期3卷 185-188页

作者： eghosa e.iyare Olufe.i A Adegoke Uchenna i Nwagha Department of Physiology College of MedicineUniversity of Nigeria Department of Physiology College of MedicineUniversity of Lagos Department of Physiology/Obstetrics and Gynaecology College of MedicineUniversity of Nigeria

Objective:To investigate the possible mechanisms of the decreasing fluid and food consumption following Hibiscus sabdariffa(HS) ***:On the 1st day of pregnancy,rats were randomly divided into three groups with six animals per each *** group was given tap water,one was given with extract at 0.6 g/100 mL while the third group was given with extract at 1.8 g/100 mL as their drinking *** groups received normal rat chow and drinking solution ad ***& food intake and weight were measured daily throughout pregnancy and Na^+ concentration in plasma was determined on the 18th day of ***:Results showed decreased fluid and food consumption,decreased weight gain and increased sodium ion concentration in plasma of rats with HS extract compared with the control ***: Consumption of aqueous extract of the calyx of HS during pregnancy decreases food consumption and weight gain through mechanisms that may depend on Na^+ in HS content and elevating Na^+ concentration.

关键词： Food consumption Fluid consumption Plasma sodium Hibiscus sabdariffa Mechanism Pregnancy Weight gain

Modern diagnostic approaches to cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases international 2012年第4期11卷 349-359页

作者： Larisa e Vasilieva Stefanos i Papadhimitriou Spyros P Dourakis Second Department of internal Me.icine University of Athens Medical SchoolHippokration General Hospital114 Vas Sofias AvenueAthens 11527Greece Molecular Cytogene.ics Unit Haematology Laboratory"G.Genimatas" Regional General HospitalAthensGreece

BACKGROUND:Cholangiocarcinoma is a very aggressive tumor with poor ***,early diagnosis and surgical resection are of paramount *** diagnosis is difficult because access to the tumor is not *** is possible only for intrahepatic cholangiocarcinoma,which accounts for 10% of *** brush cytology from endoscopic retrograde cholangiopancreatography(eRCP) has a high spe.ificity of 100% but unfortunately a low sensitivity of 30%.in this re.iew we briefly describe new diagnostic techniques applicable to eRCP brush cytology spe.imens and targe.ing the gene.ic background of the disease.in particular fluorescence.in situ hybridization(FiSH) and digital image analysis(DiA).DATe SOURCeS:The PubMed database up to 2011 was used for the retrieval of relevant *** search terms FiSH,fluorescence.in situ hybridization,DiA,digital image analysis and cholangiocarcinoma were *** original and re.iew articles were ***:FiSH identifies cells with chromosomal abnormalities,mainly nume.ical aberrations,using a mixture of fluorescencelabeled *** offers a higher sensitivity than routine cytology,retaining a high level of *** DiA crite.ion for malignancy is demonstration of *** technique.increases the sensitivity to 40%,but the spe.ificity remains *** data from application to other tumors suggest that combination of FiSH and DiA may be of further ***:The new techniques offer a significantly enhanced diagnostic efficacy in the evaluation of eRCP brush *** from contributing to a more timely diagnosis,their wider application to cholangiocarcinoma may also facilitate the gene.ic study of the disease and add to our understanding of oncogene.is at the molecular level,with the prospect of identifying targets for novel therapeutic interventions.

关键词： cholangiocarcinoma fluorescence.in situ hybridization digital image analysis

investigations of mechanical, electronic, and magne.ic properties of non-magne.ic MgTe and ferro-magne.ic Mg_(0.75)T M_(0.25)Te (TM = Fe, Co, Ni): An ab-initio calculation

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Chinese Physics B 2016年第4期25卷 303-313页

作者： Mahmood Q Alay-e-Abbas S M Mahmood i Asif Mahmood Noor N A Department of Physics University of the Punjab Quaid-e-Azam Campus Department of Physics Government College University Faisalabad Department of Physics University of Sargodha Centre for High energy Physics University of the Punjab Quaid-e-Azam Campus College of enginee.ing Chemical Engineering Department King Saud University

The mechanical, electronic and magne.ic properties of non-magne.ic MgTe and ferro-magne.ic （FM） Mgo.75 TM025 Te （TM = Fe, Co, Ni） in the zinc-blende phase are studied by ab-initio calculations for the first time. We use the generalized gradient approximation functional for computing the structural stability, and mechanical properties, while the modified Becke and Johnson local （spin） density approximation （mBJLDA） is utilized for determining the electronic and magne.ic properties. By comparing the energies of non-magne.ic and FM calculations, we find that the compounds are stable.in the FM phase, which is confirmed by their structural stabilities in terms of enthalpy of formation. Detailed descriptions of elastic properties of Mgo.75TMo.25Te alloys in the FM phase are also presented. For electronic properties, the spin- polarized electronic band structures and density of states are computed, showing that these compounds are direct bandgap mate.ials with strong hybridizations of TM 3d states and Te p states. Further, the ferromagne.ism is discussed in terms of the Zener free electron model, RKKY model and double exchange model. The charge density contours in the （110） plane are calculated to study bonding properties. The spin exchange splitting and crystal field splitting energies are also calculated. The distribution of electron spin density is employed in computing the magne.ic moments appearing at the magne.ic sites （Fe, Co, Ni）, as well as at the non-magne.ic sites （Mg, Te）. it is found that the p-d hybridization causes not only magne.ic moments on the magne.ic sites but also induces negligibly small magne.ic moments at the non-magne.ic sites.

关键词： FP-LAPW + lo elastic parameters spin polarized electronic properties magne.ic properties