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Cage type and mineral nutrition had independent impact on skeletal development in Lohmann LSL-Lite pullets from hatch to 16 weeks of age

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Animal Nutrition 2021年第3期7卷 631-640页

作者： Tanka Khanal gregoy y.Bedecarrats Elijah g.Kiarie Department of Animal Biosciences University of GuelphGuelphN1G2W1Canada

The effects of rearing cage type and dietary Ca,available P and vitamin D_(3)(VitD_(3))on body and skeletal development were studied.A total of 3,420 Lohmann LSL-Lite day-old chicks were reared in conventional(CON)or furnished cages(FUR)to 16 wk of ***,40 and 150 chicks/cage were placed in CON and FUR and transitioned to 20 and 75 chicks/cage at 8 wk of age,*** diets:Diet 1,Diet 1.5 and Diet 2 were formulated to meet nutrient specifications with Diet 1.5 and Diet 2 containing 1.5 and 2 times more Ca,P and VitD_(3)than Diet 1,*** were allocated within cage type to give 6 replicates and fed in 3 feeding programs:starter,grower and *** 4,12 and 16 wk of age,BW was recorded,and femur,tibia and blood samples for bone quality and related *** were no interactions(P>0.05)of cage type,diet and pullet age on BW,plasma Ca and inorganic P,femur and tibia morphometry,mineral density(MD),breaking strength(BS)and ash concentration(AC).Concentration of Ca,P and VitD_(3)linearly decreased BW(Pght(P=0.013).A quadratic increase on femur MD(P=0.03)and BS(P=0.026)was observed with dietary concentration of Ca,P and VitD_(3).Femur(P=0.031)was longer for CON than FUR pullets,however,femur for FUR pullets had higher(P=0.003)*** had no effect(P≥0.415)femoral MD and *** reared in FUR cages exhibited higher tibial MD(P=0.015),BS(P=0.071),AC(Py mineral content(Pge type and diets showed independent effect on femur and tibia quality with FUR pullets exhibiting enhanced indices of *** pullets twice the recommended Ca,P and VitD_(3)decreased BW,relative weight of leg bone but enhanced femoral strength with no effects on tibia attributes.

关键词： Housing Vitamin D_(3) Calcium Bone quality Mineral Pullets

Effect of yttrium Addition on Microstructural Characteristics and Superplastic Behavior of Friction Stir Processed ZK60 Alloy

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Journal of Materials Science & Technology 2013年第12期29卷 1116-1122页

作者： Z.A.Luo g.M.Xie Z.y.Ma g.L.wang g.D.wang State Key Laboratory of Rolling and Automation Northeastern University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

As-extruded ZK60 and ZK60-y magnesium alloy plates were successfully processed via friction stir processing （FSP） at a tool rotation rate of 1600 r/rain and a traverse speed of 200 mm/min. FSP resulted in the formation of equiaxed recrystallized microstructures with the average grain sizes of ,-8.5 and -4.7 μm in the ZK60 and ZK60-y alloys, respectively. Moreover, FSP broke and dispersed the MgZn2 and W-phase （Mg3Zn3y2） particles and dissolved MgZn2 phase in the FSP ZK60 alloy. With the addition of rare earth element yttrium （y） into the ZK60 alloy, the ratio of the high angle grain boundaries （HAgBs） in the FSP alloys increased from 64% to 90%, and a certain amount of twins appeared in the FSP ZK60-y alloy. The maximum elongation of 1200% and optimum strain rate of 3 X 10-3 s-1 achieved at 450 °C in the FSP ZK60-y alloy were substantially higher than those of the FSP ZK60 alloy. This is attributed to the fine grains with high ratio of HAgBs and the distribution of a large number of dispersed second phase particles with high thermal stability in the FSP ZK60-y alloy. grain boundary sliding was identified as the primary deformation mechanism in the FSP ZK60 and ZK60-y alloys from the superplastic data analyses and surficial morphology observations.

关键词： Magnesium alloy Friction stir processing Rare earth element Microstructure Superplasticity

Microstructure and mechanical behavior of laser aided additive manufactured low carbon interstitial Fe_(49.5)Mn_(30)Co_(10)Cr_(10)C_(0.5)multicomponent alloy

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Journal of Materials Science & Technology 2021年第18期77卷 38-46页

作者： y.Chew Z.g.Zhu F.Weng S.B.gao F.L.Ng B.y Lee g.J.Bi Singapore Institute of Manufacturing Technology 73 Nanyang Drive637662Singapore School of Mechanical Aerospace Engineering Nanyang Technological University50 N any ang Avenue639798Singapore

Laser aided additive manufacturing(LAAM)was used to fabricate bulk Fe_(49.5)Mn_(30)Co_(10)Cr_(10)C_(0.5)interstitial multicomponent alloy using pre-alloyed *** room temperature yield strength(σ_y),ultimate tensile strength(σ_(UTS))and elongation(ε_(UTS))were 645 MPa,917 MPa and 27.0%*** asbuilt sample consisted of equiaxed and dendritic cellular structures formed by elemental *** cellular structures together with oxide particle inclusions were deemed to strengthen the *** other contributing components include dislocation strengthening,friction stress and grain boundary *** highε_(UTS)was attributed to dislocation motion and activation of both twinning and transformation-induced plasticity(TWIP and TRIP).Tensile tests performed at-40℃and-130℃demonstrated superior tensile strength of 1041 MPa and 1267 MPa ***,almost no twinning was observed in the fractured sample tested at-40℃and-130℃.Instead,higher fraction of strain-induced hexagonal close-packed(HCP)εphase transformation of 21.2%were observed for fractured sample tested at-40℃,compared with 6.3%in fractured room temperature sample.

关键词： Multicomponent alloys Laser aided additive manufacturing Additive manufacturing Microstructure Mechanical property

Methodology for determination of correction factors in direct gamma spectrometric measurement of radionuclides in sediments

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International Journal of Sediment Research 2017年第3期32卷 324-330页

作者： Esra Uyar Alptug ?zer yksel Rufiyet gven Haluk ycel Ankara University Institute of Nuclear Sciences

In this study, the practical methodologies are described for the determination of the factors for the selfabsorption effect（Fs）, spectral interferences(Fcsi), and true coincidence summing effects(Fcoi), which are used in direct gamma-spectrometric measurement of radionuclides such as210Pb,238U,234Th,226Ra,214Pb,228Ac,208Tl,214Bi,137Cs and40K in samples. To validate the applied methods, certified reference materials（CRMs） of lake and stream sediments were measured with an n-type germanium（ge）detector-calibrated using a multinuclide reference source. The highest self-absorption correction factors ranged from Fs= 1.44-2.10 for 46.5 keV peak（210 Pb） and Fs= 1.25-1.60 for 63.3 keV peak(234Th) lying in the low energy region of the spectrum. The systematic influence was observed for 186.2 keV（226 Ra）peak due to spectral interferences with the 235 U contribution. For this peak, Fcsiis changed from 0.921 to0.955. Additionally, the present study suggests that true coincidence summing（TCS） effects are not dominant, except for 208 T1 and 214 Bi for which Fcoiranged from 1.179 to 1.192 an ranged from 1.140 to1.151, respectively.

关键词： Correction factor Self-absorption Spectral interference True coincidence summing Sediment gamma-ray spectrometry

Synthesis and characterization of salt-impregnated anodic aluminum oxide composites for low-grade heat storage

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 112-118页

作者： Bengisu yilmaz Behiye yüksel gökhan Orhan Devrim Aydin Zafer Utlu stanbul University-Cerrahpasa Faculty of EngineeringDepartment of Metallurgy and Materials EngineeringIstanbul 34320Turkey Istanbul gedik University Department of Mechanical EngineeringIstanbul 34876Turkey Eastern Mediterranean University Faculty of EngineeringDepartment of Mechanical EngineeringMersin 10Turkey

Thermochemical heat storage(THS)systems have recently attracted a lot of attention in research and *** this study,an anodic aluminum oxide(AAO)template,fabricated by a two-step anodization method,was used for the first time as the matrix material for a THS *** salts were studied as thermochemical materials for their suitability in low-grade heat storage application driven by solar energy for an open *** were prepared by absorbing CaCl2,MgCl2,LiCl,LiNO3 and mixtures of these salts under a vacuum in an AAO *** Emission Scanning Electron Microscopy was used to examine the morphology of the produced AAO *** energy storage capacities of the composites were characterized using a differential scanning *** analysis showed that anodized Al plates were suitable matrix materials for THS systems,and composite sorbent prepared with a 1:1 ratio LiCl/LiNO3 salt mixture had the highest energy value among all composites,with an energy density of 468.1 k J·kg-1.

关键词： thermal energy storage salt impregnation thermochemical heat storage anodizing salt in matrix

EFFECT OF STRUCTURAL PARAMETERS ON THE THERMAL STRESS OF A NiFe_(2)O_(4)-BASED CERMET INERT ANODE IN ALUMINUM ELECTROLySIS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 139-147页

作者： J. Li Z.g. wang y.Q. Lai y.y. Wu S.L. ye School of Metallurgy Science and Engineering Central South University Changsha 410083 China

Inert anode has been a hot issue in the aluminum industry for many decades. With the help of FEA （finite element analysis） software ANSyS, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, and the radius of inner chamfer and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the major cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.

关键词： inert anode thermal stress structural parameter aluminum electrolysis

LOW CyCLE FATIgUE AND DEFORMATION BEHAVIOR IN AN 8090 Al-Li ALLOy

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 1-11页

作者： S.H.Ai y.Q.Wu Z.g.wang y.Zhang Chinese Acad of Sciences Shenyang China

Low cycle fatigue (LCF)tests under different total strain amplitudes have been conducted in order to ascertain the effect of precipitate sizes on LCF behavior of 8090 Al-Li alloy. A constant strain rate of 3×10-3s-1 and symmetrical triangular waveform were employed for all tests. It is found that the cyclic stress response of the alloy varied with the precipitate sizes and strain amplitudes. The materials in all conditions cyclically handen at first and the higher the strain amplitude, the greater the amount of hardening. The low cyclic flow stress is the highest in the peakaged condition. TEM and SEM observations demonstrated that cyclic stress-strain behavior and fracture mode of Al-Li alloy are closely related to an increase in the dislocation density and interaction between the precipitates and dislocations, sizes of δ particles and pricipitate free zone (PFZ) at grain boundaries.

关键词： Al-Li alloy low cycle fatigue aged condition

STABLE SOLUTION OF TIME DOMAIN INTEgRAL EQUATION METHODS USINg QUADRATIC B-SPLINE TEMPORAL BASIS FUNCTIONS

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Journal of Computational Mathematics 2007年第3期25卷 374-384页

作者： M.y.Xia g.H.Zhang g.L.Dai C.H.Chan School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China Department of Electronic Engineering City University of Hong KongKowloonHong KongChina

This paper is concerned with stable solutions of time domain integral equation （TDIE） methods for transient scattering problems with 3D conducting objects. We use the quadratic B-spline function as temporal basis functions, which permits both the induced currents and induced charges to be properly approximated in terms of completeness. Because the B-spline function has the least support width among all polynomial basis functions of the same order, the resulting system matrices seem to be the sparsest. The TDIE formula-tions using induced electric polarizations as unknown function are adopted and justified. Numerical results demonstrate that the proposed approach is accurate and efficient, and no late-time instability is observed.

关键词： TDIE methods B-spline temporal basis functions Transient scattering prob-lems.

Efect of Nanometer WC Coating on Thermal Conductivity of Diamond/6061 Composites

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Acta Metallurgica Sinica(English Letters) 2023年第1期36卷 118-126页

作者： Z.y.Dong D.wang W.g.wang B.L.Xiao Z.y.Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Liaoning Shihua University Fushun 113001China

Diamond has poor interface tolerance with *** enhance interface bonding,in this study,tungsten carbide(WC)nanocoatings on the surface of diamond particles were prepared using sol–gel and in-situ reaction ***_(3) sol–gel with two concentrations,0.2 mol/L,and 0.5 mol/L,was,respectively,coated on diamond particles,then sintered at 1250℃for 2 h to produce WC *** concentration of 0.2 mol/L WO_(3) sol–gel was not enough to cover the surface of the diamond completely,while 0.5 mol/L WO_(3) sol–gel could fully cover ***,WO_(3) was preferentially deposited on{100}planes of the ***_(3) converted to WC in-situ nanocoatings after sintering due to the in-situ reaction of WO_(3) and *** diamond-reinforced Al composites with and without WC coating were fabricated by powder *** diamond/Al composite without coating has a thermal conductivity of 584.7 W/mK,while the composite with a coating formed by 0.2 mol/L and 0.5 mol/L WO_(3) sol–gel showed thermal conductivities of 626.1 W/mK and 584.2 W/mK,*** moderate thickness of nanocoatings formed by 0.2 mol/L WO_(3) sol–gel could enhance interface bonding,therefore improving thermal *** nanocoating produced by 0.5 mol/L WO_(3) sol–gel cracked during the fabrication of the composite,leading to Al12W formation and a decrease in thermal conductivity.

关键词： Diamond Al matrix composite Nanometer coating WC Thermal conductivity