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chinese Journal of Polymer Science 2007年第5期25卷 519-523页

作者： n.c. dafader m.e. haque.f. akhtar n.c.ear and Radiation.c.emistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

natural rubber latex （nRL） and methyl methacrylate （mmA） grafted rubber latex were blended in different ratios and irradiated at various absorbed doses by gamma rays from co-60 source at room tem.e.ature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of 8 kGy. modulus increases from 6.99 mPa to 9.87 mPa for an increase in proportion of mmA grafted rubber from 40% to 60% in the blend at similar absorbed dose. elongation at break and swelling ratio decrease with increasing absorbed dose as well as the mmA grafted rubber content in the blends. The decreasing trend of permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost flat.

关键词： natural rubber latex mmA grafted rubber latex Blend rubber Irradiation cross-link.

VARIATIOn Of PHYSIcO-cHemIcAL PROPeRTIeS Of RADIATIOn.c.OSSLInKeD RUBBeR WITH STORAGe TIme

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chinese Journal of Polymer Science 2005年第5期23卷 497-501页

作者： n.c.dafader m.e.haque.f.akhtar n.c.ear and Radiation.c.emistry Division

The effect of storage on physico-chemical properties of non-irradiated natural rubber and radiation vulcanized natural rubber （RVnR） were evaluated. The rubber films were stored under two different conditions, namely in open air and sealed polyethylene bags. The antioxidant, tris（nonylated phenyl） phosphite （TnPP） was used for preventing degradation of RVnR films. Gel content, cross-link density, tensile strength at break and 500% elongation of rubber films were measured. The results show that the retention （%） of tensile properties of rubber films with TnPP is higher than that of rubber films without antioxidants. The rubber films stored in polyethylene bags also show better retention of tensile properties than those of rubber films stored in open air.

关键词： Storage Radiation Tensile Properties Antioxidant.

Design of multilayer hybrid sol-gel coatings with bifunctional barrier-bioactive response on the elektron 21 magnesium alloy for biomedical applications

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Journal of magnesium and Alloys 2021年第6期9卷 2097-2112页

作者： K.S.Durán n.Hernández L.m.Rueda c.A.Hernández-Barrios A.e.coy f.Viejo Grupo de Investigación en Desarrollo y Tecnología de nuevos materiales(GImAT) Universidad Industrial de Santander9 Cra.27Colombia Grupo de Investigación de las ciencias de las Ingenierías(GIcI) Universidad de San BuenaventuraCartagenaCalle Real de TerneraDiagonal 32#30-966Colombia

The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate(TeOS)and glycidoxypropyltriethoxysilane(GPTmS)deposited on the elektron 21 magnesium *** purpose of the inner layer(barrier coating)was to provide corrosion protection to the magnesium alloy,whereas the outer layer(bioactive coating)was doped with different ca and mg contents to produce a bioactive *** coatings were characterised using scanning electron microscopy(Sem)and their corrosion behaviour was evaluated by anodic polarisation and electrochemical im.e.ance spectroscopy after im.e.sion in simulated body fluid(SBf)at 37±0.5°*** experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during im.e.sion in SBf *** the other hand,the presence of ca and mg in the bioactive coating promoted the growth of apatite-like ***,an increment of salt content favoured the formation of porous coatings,which allowed the access of the electrolyte to the substrate leading to their rapid *** the latter,this research endorses the premise that the TeOS-GPTmS hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

关键词： magnesium bioactivity coating sol-gel eIS corrosion

Regularized quantile regression for SnP marker estimation of pig growth curves

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Journal of Animal Science and Biotechnology 2017年第4期8卷 824-832页

作者： L.m.A.Barroso m.nascimento A.c.c.nascimento1 f.f.Silva n.V.L.Serao c.D.cruz m.D.V.Resende f.L.Silva c.f.Azevedo P.S.Lopes S.e.f.Guimaraes Department of Statistics Federal University of Vicosa Av. P H Rolfs s/nUniversity Campus Vicosa MG 36570-000 Brazil Department of Animal Science Federal University of Vicosa Av. P H Rolfs s/n University CampusVicosa MG 36570-000 Brazil Department of Animal Science Iowa State University Kildee Hall 50011 Ames Iowa USA Department of General Biology Federal University of Vicosa Av. P H Rolfs s/n University CampusVicosa MG 36570-000 Brazil embrapa forestry Estrada da Ribeira km 111Colombo PR Brazil. Department of Plant Science Federal University of Vicosa Av. P H Rolfs s/n University Campus Vicosa MG 36570-000 Brazil

Background: Genomic growth curves are general y defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression(QR). This methodology allows for the estimation of marker effects at different levels of the variable of interest. We aimed to propose and evaluate a regularized quantile regression for SnP marker effect estimation of pig growth curves, as well as to identify the chromosome regions of the most relevant markers and to estimate the genetic individual weight trajectory over time(genomic growth curve) under different quantiles(levels).Results: The regularized quantile regression(RQR) enabled the discovery, at different levels of interest(quantiles), of the most relevant markers al owing for the identification of QTL regions. We found the same relevant markers simultaneously affecting different growth curve parameters(mature weight and maturity rate): two(ALGA0096701 and ALGA0029483)for RQR(0.2), one(ALGA0096701) for RQR(0.5), and one(ALGA0003761) for RQR(0.8). Three average genomic growth curves were obtained and the behavior was explained by the curve in quantile 0.2, which differed from the ***: RQR allowed for the construction of genomic growth curves, which is the key to identifying and selecting the most desirable animals for breeding purposes. furthermore, the proposed model enabled us to find, at different levels of interest(quantiles), the most relevant markers for each trait(growth curve parameter estimates) and their respective chromosomal positions(identification of new QTL regions for growth curves in pigs). These markers can be exploited under the context of marker assisted selection while aiming to change the shape of pig growth curves.

关键词： Genome association Growth curve Pig QTL Regularized quantile regression

Inversion of electrical mobility measurements using bipolar or unipolar chargers for the arbitrary distribution of channels

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Particuology 2015年第3期13卷 114-123页

作者： m.Domat f.e.Kruis n.L.Azong-Wara J.m.fernandez-Diaz Department of Physics University of OviedoC/Calvo Sotelos/nE-33007 OviedoSpain Institute of Technology for nanostructures(nST) and center for nanointegration Duisburg-essen.c.nIDe) University of Duisburg-EssenBismarckstr.81D-47057 DuisburgGermany

The inversion of the particle size distribution from.e.ectrical mobility measurements is analyzed. Three different methods are adapted for a dot-matrix approach to the problem, especially for non-square or singular matrices, and applied to electrical mobility measurements from fixed or scanning voltages. mul- tiply charged particles, diffusion losses, arbitrary voltage steps and noise were considered, which results in non-adjoining and overlapping transfer functions. The individual contribution of the transfer func- tions in each size interval was geometrically estimated, which requires only its characteristic mobilities. The methodology is applied to mobility measurements from particles charged with unipolar and bipolar chargers. However, the method can be extrapolated to any charging method with a defined charge distribution, and retrieval of the singly charged particle distribution and mean.c.arge from a tandem differential mobility analysis configuration was successfully demonstrated.

关键词： Tandem differential mobility analysisInverse problem.e.ularization methodsSize distributionTransfer functionUnipolar charger

effect of Ringer's Solution on Wear and friction of Stainless Steel 316L after Plasma electrolytic nitrocarburising at Low Voltages

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Journal of materials Science & Technology 2011年第10期27卷 906-912页

作者： n.Afsar Kazerooni m.e.Bahrololoom m.H.Shariat f.mahzoon T.Jozaghi Department of materials Science and engineering Shiraz University

A plasma electrolytic nitrocarburising （Pen.c. process was performed on stainless steel 316L to improve the surface properties for using as medical implants. A bath was optimised to reduce the required voltage to 150 volts. Aqueous urea-based solutions with 10% nH4cl were prepared with slightly different amounts of na2cO3 to optimise the electrolyte composition. The surface and the cross-section morphologies were studied by scanning electron microscopy. The microstructure and the chemical composition of samples were investigated by X-ray diffraction （XRD） and energy dispersive X-ray （eDX） techniques. The microstructure of the outer layer of the coatings was found to be a complex oxide containing cr and fe. The wear properties of the samples were examined by using a pin on disk wear test with Ringer＇s solution and were compared with their wear properties in the ambient atmosphere. The Ringe（s solution acted as a lubricant, reducing friction.c.efficient. Hardness and roughness were also studied. The bath with the composition of 10% nH4cI and 3% na2cO3 exhibited the best tribological properties. The results showed that the tribological properties of treated samples were improved and the wear mechanism was abrasion of the pin.

关键词： Plasma electrolytic nitrocarburising Ringer's solution Tribological properties

effect of combined Use of Brackish Water and nitrogen fertilizer on Biomass and Sugar Yield of Sweet Sorghum

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Pedosphere 2012年第6期22卷 785-794页

作者： T.B.RAmOS n.L.cASTAnHeIRA m.c.GOnALVeS m.L.feRnAnDeS m.I.JAnURIO m.e.LOURenO f.P.PIReS J.c.mARTInS ceeR-Biosystems engineering Institute of Agronomy Technical University of Lisbon Tapada da Ajuda 1349-017 Lisbon (Portugal) estao Agronómica n.c.onal L-INIA Instituto Nacional de Recursos Biológicos Quinta do Marquês Av. República 2784-505 Oeiras (Portugal) Departamento de fitotecnia Instituto de Ci encias Agrrias e Ambientais Mediterrnicas Universidade de vora Apartado 94 7002-554 vora (Portugal)

Soil salinization and non-point source pollution are among the most important and widespread environmental problems in european mediterranean regions. Sweet sorghum （Sorghum bicolor （L.） m.e.ch var. saccharatum） is a moderate to high salinity tolerant crop with low water and nutrient needs, seen as an alternative to grow in the water scarce regions. A three-year multifactorial study was conducted in southern Portugal to evaluate the combined effects of saline water and nitrogen application on the dry biomass （total, stems, and leaves）, sugar content （total reducing sugars and sucrose eontents） and sugar yield （here defined as the product of total reducing sugars and stems dry biomass） functions of sweet sorghum. Sorghum dry biomass and sugar yield showed diminishing returns for each incremental change of nitrogen. The use of saline irrigation waters also led to yield reduction. exception was sucrose content which increased with increasing levels of sodium in the soil. nitrogen need decreased as the amount of sodium applied increased. Stem dry biomass, sucrose content, and sugar yield progressively increased with progress in the experiment. The effect could be attributed to the increase of the amount of irrigation applied throughout the years, thus increasing the leaching fraction which promoted salt leaching from the root zone, reduced the salinity stress, increased plant transpiration, nitrogen uptake and biomass yield.

关键词： mediterranean.c.nditions non-point source pollution salinity sweet sorghum yield functions

Improvements in tribological and anticorrosion performance of porous Ti–6Al–4V via PeO coating

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friction 2021年第5期9卷 1303-1318页

作者： c.Garcia-cabezón m.L.Rodríguez-méndez V.AmigóBorrás R.Bayón.c.Salvo-comino c.Garcia-Hernandez f.martin-Pedrosa materials engineering E.I.I.Universidad de ValladolidValladolid 47011Spain BioecoUVA Research Institute Universidad de ValladolidValladolid 47011Spain Group UVASenS Escuela de Ingenierías IndustrialesUniversidad de ValladolidValladolid 47011Spain Instituto de Tecnología de materials Univesitat Politécnica de ValenciaValencia 46022Spain Tribology Unit Fundación IK4-TeknikerEibar 20600Spain

medical implants manufactured using biomaterial Ti–6Al–4V exhibit some *** higher elastic modulus than that of natural bone can.c.use stress shielding *** can be avoided using Ti–6Al–4V with pores in the implant ***,poor corrosion and tribocorrosion behaviors are yielded because of the large area exposed to the *** mitigate both issues,coating technologies can be *** plasma electrolytic oxidation(PeO)process is a cost‐effective process that has been used successfully in nonporous Ti *** this study,two PeO coatings with different amounts of ca/P are ***,reports regarding their application in porous materials are *** effects of PeO treatments on.c.rrosion and tribocorrosion in Ti–6Al–4V powder metallurgy are analyzed *** porous materials provide an efficient surface for PeO coatings,as demonstrated via scanning electron microscopy(Sem)and atomic force microscopy(Afm),and the porosity of the substrates improved the adherence of the *** corrosion resistance measured via electrochemical im.e.ance spectroscopy confirmed the beneficial effect of the coatings,particularly for long exposure *** lower roughness,small pore size,and more compact film observed in the PeO–ca/P sample resulted in favorable tribological and corrosion properties.

关键词： Ti‐based alloys corrosion tribocorrosion surface modification

Study of the structural,ferroelectric,dielectric,and pyroelectric properties of the K0.5na0.5nbO3 system doped with Li+,La3+,and Ti4+

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Journal of Advanced ceramics 2020年第3期9卷 329-338页

作者： c.mOnTeRO-TAVeRA m.D.DURRUTHY-RODRiGUeZ f.D.cORTeS-VeGA J.m.YAneZ-LImOn center for Research and Advanced Studies of IPn Campus QueretaroMexico national evangelical University Paseo de los Periodistas#54Ensanche MirafloresSanto DomingoDistrito NacionalRepiblica Dominicana

Pure *** snbO3(Knn)and Knn doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state *** effects of the dopant on the physical properties of pure Knn have been evaluated based on the structural,ferroelectric,pyroelectric,and dielectric *** XRD measurements show that Knn pure sample contains a mixture of mon.c.in.c.and orthorhombic crystalline phases,with a slightly higher concentration of mon.c.in.c.*** contrast,all doped samples show a higher concentration of the orthorhombic phase,as well as the presence of a secondary phase(K6nb10.8O3o),also detected by Raman *** samples with a higher concentration of this secondary phase,also present greater dielectric losses and lower values of remnant *** dielectric measurements allowed us to detect tem.e.atures of structural transitions(orthorhombic-tetragonal,O-T)previous to the ferroelectric paraelectric transition(tetragonal-cubic,T-c),and also in this set of samples,a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.

关键词： K0.5na0.5nbO3(Knn) lead-free solid-state reaction structural properties pyroelectric properties dielectric properties Li,La,Ti doping elements

Sensory quality of meat from.e.ght different types of cattle in relation with their biochemical characteristics

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Journal of Integrative Agriculture 2016年第7期15卷 1550-1563页

作者： m Gagaoua e m c Terlouw D micol J-f Hocquette A P moloney K nuernberg D Bauchart A Boudjellal n D Scollan R I Richardson B Picard InRA UMRH 1213Unite de Recherches sur les HerbivoresTheix63122 Saint Genes ChampanelleFrance VetAgro Sup UMRH 1213Unite de Recherches surles HerbivoresTheix63122 Saint Genes ChampanelleFrance equipe maquav INA TAAUniversite Freres Mentouri ConstantineRoute de Ain El-Bey25000 ConstantineAlgeria Teagasc Animal and Grassland Research and Innovation CentreGrangeDunsanyCo.MeathIreland fBn Leibniz Institute for farm Animal Biology W-StahI-Allee 218196 DummerstorfGermany Institute of Biological Environmental and Rural Sciences(IBERS)Aberystwyth UniversityGogerddanAberystwyth SY23 3EBUnited Kingdom Division of farm Animal Science University of BristolLangford HouseBristol BS40 5DUUnited Kingdom

The present study compared eight breeds of cattle differing in gender （heifers, buls and steers） to determine associations between muscle characteristics and meat sensory qualities of theLongissimus thoracis muscle. Animal types differed in al the muscle characteristics and sensory qualities. many correlations among muscle characteristics and among sensory qualities were consistent for most animal types. Isocitrate dehydrogenase （IcDH） activities alowed discrimination of muscles with respect to myosin heavy chain （myHc）-I proportions for al animal types. Lactate dehydrogenase （LDH） and phos-phofructokinase （PfK） activities were positively correlated for most animal types. Overal liking was correlated with beef lfavour and abnormal lfavour in al animal types and with global tenderness for al animal types except for charolais cross breed steers. for al animal types except for Angus×friesian heifers, beef lfavour and abnormal lfavour were negatively correlated. Overal liking was not correlated with juiciness. PfK, IcDH and citrate synthase （cS） activities were strongly associated with tenderness, beef lfavour and overal liking when average values for al animal types were used. However, associations between muscle characteristics and sensory qualities within animal types were weak and inconsistent.

关键词： cattle muscle characteristics meat sensory qualities gender breed prediction