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Structural integrity evaluation of irradiated LEU targets for the production of molybdenum‑99 using thermo‑mechanical behavior simulation coupled with pressure of fission gas release calculation

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Nuclear Science and Techniques 2022年第12期33卷 12-23页

作者： N.mellel b.mohammedi m.Salhi m.Dougdag S.missaoui S.Hanini birine Nuclear Research Center PB 18017200 Ain OusseraDjelfaAlgeria LbmPT UniversitéDr Yahia Farès 26000 MédéaAlgeria

Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nuclear medicine.The behavior of this type of target must be known to prevent eventual failures during radiation.The present study aims to assess,via prediction,the thermal–mechanical behavior,physical integrity,and geometric stability of targets under neutron radiation in a nuclear reactor.For this purpose,a numerical simulation using a three-dimensional finite element analysis model was performed to determine the thermal expansion and stress distribution in the target cladding.The neutronic calculation results,target material properties,and cooling parameters of the KAERI research group were used as inputs in our developed model.Thermally induced stress and deflection on the target were calculated using Ansys-Fluent codes,and the temperature profiles,as inputs of this calculation,were obtained from a CFD thermal–hydraulic model.The stress generated,induced by the pressure of fission gas release at the interface of the cladding target,was also estimated using the Redlich–Kwong equation of state.The results obtained using the bonded and unbonded target models considering the effect of the radiation heat combined with a fission gas release rate of approximately 3%show that the predicted thermal stress and deflection values satisfy the structural performance requirement and safety design.It can be presumed that the integrity of the target cladding is maintained under these conditions.

关键词： Irradiated LEU target mo-99 production Integrity evaluation Thermo-mechanical analyses Fission gas pressure

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Effects of magnetic Reynolds number on swimming of gyrotactic microorganisms between rotating circular plates filled with nanofluids

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Applied mathematics and mechanics(English Edition) 2020年第4期41卷 637-654页

作者： Lijun ZHANG m.b.ARAIN m.m.bHATTI A.ZEESHAN H.HAL-SULAmI College of mathematics and Systems Science Shandong University of Science and Technology Nonlinear Analysis and Applied mathematics (NAAm)-Research Group Department of Mathematics Faculty of Science King Abdulaziz University Department of mathematics and Statistics International Islamic University

The three-dimensional(3D) nano?uid ?ow among the rotating circular plates ?lled with nanoparticles and gyrotactic microorganisms is studied. A generalized form of the magnetic Reynolds number is used for the mathematical modeling of the ferro-nano?uid ?ow. The torque e?ects on the lower and upper plates are calculated.A di?erential transform scheme with the Pad′e approximation is used to solve the coupled highly nonlinear ordinary di?erential equations. The results show that the squeeze Reynolds number signi?cantly suppresses the temperature, microorganism, and nanoparticle concentration distribution, and agree well with those obtained by the numerical method.

关键词： swimming of microorganism generalized magnetic Reynolds number nanofluid differential transform solution circular rotating plate

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Clinical potential of tensionlengthening strategies during nerve repair

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Neural Regeneration Research 2022年第4期17卷 779-780页

作者： Stanley bazarek Justin m.brown Sameer b.Shah Department of Neurosurgery Massachusetts General Hospital/Harvard Medical SchoolBostonMAUSA Department of Neurosurgery Brigham&Women’s Hospital/Harvard Medical SchoolBostonMAUSA Departments of Orthopedic Surgery and bioengineering University of California-San DiegoLa JollaCAUSA

A(very)brief history of tension in nerve repair:Successful nerve repair is achieved by conveying as many axons successfully to their targets as possible.Typically,this is best achieved through a direct end-to-end repair under minimal tension(millesi,1986).However,this is not feasible in most cases of trauma,where a segment of tissue damage must be excised and overcome.This has most commonly been addressed with the use of nerve grafts to bridge the gap.Autologous nerve grafts are considered the gold standard,with allograft or synthetic substitutes demonstrating some success over shorter distances.Despite their utility,autologous grafts pose challenges of their own.These include functional deficit in the donor distribution(typically sensory),extended operative duration,additional scarring,and a lack of intrinsic blood supply.They are also a poor anatomical match for the stumps being bridged,both internally(disparate neuronal size and composition)as well as externally(often requiring cabled bundles to approximate the caliber of the nerve being repaired).Finally,unlike end-to-end repairs,autologous grafts also require axons to traverse a second repair interface,where a large proportion of axons are lost across the anatomical discontinuity.

关键词： tension repair overcome

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Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： m.b.KIRKHAm Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the moon or mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the moon and mars.

关键词： soils soil bases

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Design and validation of a handheld capnography device for cardiopulmonary assessment based on the Arduino platform

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Journal of Innovative Optical Health Sciences 2021年第6期4卷 42-54页

作者： Om Prakash Singh Ismail m.El-badawy m.b.malarvili bio-signal Processing Research Group(bSPRG)School of biosciences and medical Engineering Universiti Teknologi malaysia(UTm) 81310 SkudaiJohorMalaysia Electronics and Communication Engineering Department Arab Academy for Science and Technology CairoEgypt School of Electrical Engineering Universiti Teknologi Malaysia(UTM)81310 SkudaiJohorMalaysia bio-Signal Processing Research Group(bSPRG)School of biosciences and medical Engineering Universiti Teknologi malaysia(UTm) 81310 SkudaiJohorMalaysia

The design of a handheld capnography device is in great demand because of its effective and practical uses in all cardiac arrest resuscitations,according to the recommendation of the American Heart Association.Herein,a handheld capnography device that can be used in clinical settings and the home environment is reported.The proposed device was developed by using an infrared CO_(2)sensor,Arduino mega2560,and a high-resolution display(2.8").Furthermore,two rechargeable batteries(7.6 V,0.99 A)and a secure digital card with a capacity of 16 Gb were incorporated to increase the portability and usability of the device.Algorithms were implemented to measure standard features,namely,inspired CO_(2)(ICO_(2)),end-tidal CO_(2)(EtCO_(2)),and re-spiratory rate(RR).The features of 15 healthy subjects were recorded by using the developed prototype and the standard capnography device(Capnostream^(Tm)20 model CS08798).Validation was performed with bland-Altman plots.Findings revealed that mean differences±standard deviations for the set limits of ICO_(2),EtCO_(2)and RR were 0.29±1.30 millimeters of mercury(mmHg),0.15±1.77 mmHg and 0.40±0.97 breaths per minute(bpm),respectively.most of the differences among device measurements across all features fell within the 95%limits of agreement.Thus,the developed device may help manage respiratory distress conditions in and outside of a hospital setting.

关键词： Arduino board capnogram carbon dioxide sensor cardiorespiratory monitoring system

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Alloy design by dislocation engineering

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Journal of materials Science & Technology 2018年第3期34卷 417-420页

作者： m.X.Huang b.b.He Department of mechanical Engineering The University of Hong Kong

Ultra-high strength alloys with good ductility are ideal materials for lightweight structural application in various industries. However, improving the strength of alloys frequently results in a reduction in ductility, which is known as the strength-ductility trade-off in metallic materials. Current alloy design strategies for improving the ductility of ultra-high strength alloys mainly focus on the selection of alloy composition （atomic length scale） or manipulating ultra-fine and nano-grained microstructure （grain length scale）. The intermediate length scale between atomic and grain scales is the dislocation length scale. A new alloy design concept based on such dislocation length scale, namely dislocation engineering, is illustrated in the present work. This dislocation engineering concept has been successfully substantiated by the design and fabrication of a deformed and partitioned （D＆P） steel with a yield strength of 2,2 GPa and an uniform elongation of 16%. In this D＆P steel, high dislocation density can not only increase strength but also improve ductility. High dislocation density is mainly responsible for the improved yield strength through dislocation forest hardening, whilst the improved ductility is achieved by the glide of intensive mobile dislocations and well-controlled transformation-induced plasticity （TRIP） effect, both of which are governed by the high dislocation density resulting from warm rolling and martensitic transformation during cold rolling. In addition, the present work proposes for the first time to apply such dislocation engineering concept to the quenching and partitioning （Q＆P） steel by incorporating a warm rolling process prior to the quenching step, with an aim to improve simultaneously the strength and ductility of the Q＆P steel. It is believed that dislocation engineering provides a new promising alloy design strategy for producing novel strong and ductile alloys.

关键词： Alioy design Dislocation engineering D＆P steel Q＆P steel TRIP Warm rolling

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Distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naphthofurans in source rock extracts from Niger Delta basin,Nigeria

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Acta Geochimica 2020年第6期39卷 973-987页

作者： Abiodun b.Ogbesejana Oluwasesan m.bello Department of Applied Chemistry Federal University Dutsin-MaP.M.B.5001Dutsin-MaKatsina StateNigeria

The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matography--mass spectrometry(GC--mS).The data obtained from the source rocks evaluation showed that the rock samples contained type 1/III kerogen capable of generating oil and gas and were within immature to early mature stage.The relative abundance of the Cor,C1-and C2-dibenzofurans range from 1.75%to 29.82%,27.60%to 40.52%and 29.66%to 6889%,respectively.The diben-zofurans were dominated by C-dibenzofurans.Among the C1-dibenzofurans,2-+3-methyldibenzofuran was the most abundant in the rock samples while 1-methy ldibenzofuran appeared to be the least.The relative abundance of benzo[b]naphtho[1,2-d]furan(1,2]bNF),benzo[b]naph-tha[2,1-d]furan(2.1]bNF)and benzo[b]naphtha[2,3-d]fu-ran([2.3]bNF)in the rock extracts range from 12.01%to 52.58%,32.61%to 75.219%and 10.27%to 52.43%.The wide range of values recorded for the three isomers of benzo[b lnapthofurans in the samples suggest source rocks formed from mixed organic matter.Among the pheny ldibenzofuran isomers,4-pheny ldibenzofuran was the most abundant while 1-phenyldibenzofuran was the least.Phenyldibenzofuran ratio-1(PhFR-1)and pheny ldibenzofuran ratio-2(PhFR-2)values range from 0.13 to 1.20 and 0.11 to 2.11,respectively.The resuls showed that the relative abundance of PhFR-1 and PhFR-2 increase gradually with increasing burial depth and maturity(VRo≤0.77%,mPI-1≤0.62.Tmax s 443℃),and have a good correlations with calculated vitrinite reflectance.mPI-I and maximum Temperature(Tmax)-This range of values suggested immature to early mature source rocks.The source rocks were found to have shale and coul lithologics and deposited in a lacustrine/fuvial deltaic settings within immature to early mature stages based on the distribution of dibenzofurans,pheny ldiben-zofurans and benzo[b]naphthofurans in the source rocks.This study showed that dibenzof urans,phenyldi

关键词： Dibenzofurans benzo[b]napthofurans Source rocks Niger delta Gas chromatography-mass spectrometry

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Crashworthiness performance of hybrid kenaf/glass fiber reinforced epoxy tube on winding orientation effect under quasi-static compression load

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Defence Technology（防务技术） 2020年第5期16卷 1051-1061页

作者： A.b.m.Supian S.m.Sapuan m.Y.m.Zuhri E.S.Zainudin H.H.Ya Advanced Engineering materials and Composites Research Centre Department of Mechanical and Manufacturing EngineeringUniversiti Putra Malaysia43400UPM SerdangSelangorMalaysia Laboratory of biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400UPM SerdangSelangorMalaysia Department of mechanical Engineering Universiti Teknologi Petronas32610Seri IskandarPerakMalaysia

This research was aimed to study the effect winding orientation on the crashworthiness performance of hybrid tube.The specimens tested under quasi-static compression load involve of three winding parameters(q?30,45and 70)of hybrid kenaf/glass fiber reinforced epoxy and glass fiber reinforced epoxy as contrast specimen.The automated filament winding technique has been used in fabrication of hybrid and non-hybrid composite tube and crashworthiness performance was investigated experimentally.The effects of winding orientation on energy absorption capabilities and crashworthiness characteristic were investigated through quasi-static compression load and the result are compared with the glass fiber composite tube to justify the capability of hybrid natural/synthetic as energy absorption application.Hybridized samples proved to enhancing the progressive crushing capability as combination of local buckling,delaminate and brittle fracturing as progressive crushing modes.In the view of winding orientation aspect,the results of high winding orientation of hybrid composite tube elevated the crush load efficiency,specific energy absorption and energy absorption capability compared to glass composite tube(GFRP).The hybrid kenaf/glass composite tube with high winding orientation showed the best winding orientation to enhance the energy absorber characteristics as energy absorption application.

关键词： composite laminate winding

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Evolution of metabolic scaling among the tetrapod:effect of phylogeny,the geologic time of class formation,and uniformity of species within a class

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Integrative Zoology 2022年第5期17卷 904-917页

作者： Valery m.GAVRILOV Tatiana b.GOLUbEVA Andrey V.bUSHUEV Department of Vertebrate Zoology M.V.Lomonosov Moscow State UniversityMoscowRussia Zvenigorod biological Station M.V.Lomonosov Moscow State UniversityMoscowRussia

The metabolic scaling in the animal has been discussed for over 90 years,but no consensus has been reached.Our analysis of 2126 species of vertebrates reveals a signiﬁcant allometric exponent heterogeneity.We show that classes of terrestrial vertebrates exhibit the evolution of metabolic scaling.both the allometric coefﬁcient“a”and the allometric exponent“b”change naturally,but differently depending on the geological time of group forma-tion.The allometric coefﬁcient“a”shows the measure of the evolutionary development of systems that forms resting metabolism in animals.Endothermic classes,such as birds and mammals,have a metabolic rate that is in an order of magnitude higher than that in ectothermic classes,including amphibians and reptiles.In the terrestrial vertebrate phylogeny,weﬁnd that the metabolic scaling is characterized by 3 main allometric exponent values:b=3/4(mammals),b>3/4(ectotherms,such as amphibians and reptiles),and bbirds).The hetero-geneity of the allometric exponent is a natural phenomenon associated with the general evolution of vertebrates.The scaling factor decreases depending on both the external design and the size(birds vs mammals)of the an-imal.The metabolic rate and uniformity of species within a class increase as the geological start date of for-mation of the class approaches the present time.The higher the mass-speciﬁc standard metabolic rate in the class,the slower metabolic rate grows with increasing body size in this class.Our results lay the groundwork for further exploration of the evolutionary and ecological aspects of the development of metabolic scaling in animals.

关键词： geological time metabolic rate scaling

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Influences of ascorbic acid and gibberellic acid in alleviating effects of salinity in Petunia under in vitro

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Phyton-International Journal of Experimental botany 2019年第1期88卷 15-23页

作者： Krupa-małkiewicz m b Smolik m Sędzik Department of Plant Genetics Breeding and BiotechnologyWest Pomeranian University of Technology in SzczecinSłowackiego str.71-434 SzczecinPoland Department of Plant Physiology and biochemistry West Pomeranian University of Technology in SzczecinSłowackiego str.71-434 SzczecinPoland

Salinity is one of the abiotic stresses that limits the growth and productivity of many crops.A possible survival strategy for plant under saline conditions is to use compounds that could minimize the harmful effects of salt stress on the plant development.The objective of the presented study was to investigate the effect of exogenous ascorbic acid(ASA)with or without gibberellic acid(GA3)on key growth and biochemical parameters in two petunia cultivars‘Prism Rose’and‘Prism White’under saline(150 mm NaCl)and non-saline in vitro condition.Nodal cutting with an axillary buds were used as explants.Application of 1 mm ascorbic acid with or without 0.05 mm gibberellic acid into the mS medium stimulated the length of shoots and the number of new shoots of‘Prism Rose’;whereas,it decreased the root length and the number of roots of both‘Prism Rose’and‘Prism White’under non-saline condition.The addition of ascorbic acid with or without gibberellic acid into the mS medium under saline condition,increased the length of plants and the number of new shoots,but did not affect their root number and length.NaCl treatments increased the proline content and lipid peroxidation which was indicated by the accumulation of malondialdehyde(mDA).The study revealed a correlation between chlorophylls a and b content and the leaf pigmentation intensity–parameter a*.Addition of 1 mm ascorbic acid with 0.05 mm gibberellic acid into the mS medium plays a protective role in salinity tolerance by improving the shoot growth and the development as well as increasing the activities of the antioxidant enzymes and other antioxidant substances.

关键词： AsA GA3 micropropagation Petunia x atkinsiana D.Don Salinity

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