检索结果-南通市图书馆

cognition on oxidation behavior of Ni-based superalloy GH4742 when exposed to water vapor

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第7期174卷 15-22页

作者： H.Xu S.F.Yang E.H.Wang c.Y.Guo Y.S.liu X.M.Hou Y.l.Zhang State Key laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute for carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The oxidation behavior of Ni-based superalloy GH4742 exposed to water vapor was investigated at 900-1100℃for 50 h in Ar+20%H_(2)O,with Ar+20%O_(2)included for *** presence of H_(2)O is adverse to formation of continuous cr_(2)O_(3)oxide layer but contributes to generation of big *** on this,Ni^(2+)and co^(2+)are more easily to diffuse towards the outermost oxide layer(OOl),forming non-protective Ni-and co-rich oxides with high *** leads to a higher weight gain in Ar+20%H_(2)O than that in Ar+20%O_(2).At elevated temperatures,the spallation of oxide scale occurs while the consumption of cr is reduced in Ar+20%H_(2)O,and the contents of Ni-and co-rich oxides at this moment are reduced in the *** oxidation mechanism was also discussed.

关键词： GH4742 Superalloy H_(2)O Diffusion Oxidation Mechanism

Sensitivity of precipitation statistics to urban growth in a subtropical coastal megacity cluster

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第9期29卷 6-12页

作者： christopher claus Holst johnny c.l.chan chi-Yung Tam School of Energy and Enuironment City Uniuersity of liong KongHong KongChina Guy carpenter Asia-Pacific climate Impact centre City Uniuersity of Hong KongHong KongChina Earth System Science Programme The Chinese Uniuersity of Hong KongHong KongChina

This short paper presents an investigation on how human activities may or may not affect precipitation based on numerical simulations of precipitation in a benchmark case with modified lower boundary conditions, representing different stages of urban development in the model. The results indicate that certain degrees of urbanization affect the likelihood of heavy precipitation significantly, while less urbanized or smaller cities are much less prone to these effects. Such a result can be explained based on our previous work where the sensitivity of precipitation statistics to surface anthropogenic heat sources lies in the generation of buoyancy and turbulence in the planetary boundary layer and dissipation through triggering of convection. Thus only mega cities of sufficient size, and hence human-activity-related anthropogenic heat emission, can expect to experience such effects. In other words, as cities grow, their effects upon precipitation appear to grow as well.

关键词： Urban precipitation Micro climate sensitivity Urbanization

comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable Mg-3Y alloy prepared by selective laser melting and spark plasma sintering

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.Minárik M.Zemková S.Šašek J.Dittrich M.Knapek F.lukáˇc D.Koutný J.Jaroš R.Král Faculty of Mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of Machine and Industrial Design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SlM).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SlM material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 MPa in tension and compression and relatively good deformability of∼9%and∼21%for the SlM and SPS materials,*** corrosion resistance of the SPS material in 0.1 M Nacl solution was superior to the SlM one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SlM *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： Magnesium Yttrium Powder metallurgy Microstructure Mechanical strength corrosion resistance

Importance of Air-Sea coupling in Simulating Tropical cyclone Intensity at landfall

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2022年第10期39卷 1777-1786页

作者： charlie c.F.lOK johnny c.l.cHAN Ralf TOUMI School of Energy and Environment City University of Hong KongHong KongChina Department of Physics Imperial CollegeLondon SW72AZUK

An atmosphere-only model system for making seasonal prediction and projecting future intensities of landfalling tropical cyclones(Tcs)along the South china coast is upgraded by including ocean and wave models.A total of 642 Tcs have been re-simulated using the new system to produce a climatology of Tc intensity in the South china *** comparisons of the simulations from the atmosphere-only and the fully coupled systems reveal that the inclusion of the additional ocean and wave models enable differential sea surface temperature responses to various Tc characteristics such as translational speed and *** particular,interaction with the ocean does not necessarily imply a weakening of the Tc,with the coastal bathymetry possibly playing a role in causing a near-shore intensification of the *** results suggest that to simulate the evolution of Tc structure more accurately,it is essential to use an air-sea coupled model instead of an atmosphere-only model.

关键词： tropical cyclone intensity tropical cyclone landfall seasonal prediction air-sea coupling

Extracellular vesicles-coupled miRNAs from oviduct and uterus modulate signaling pathways related to lipid metabolism and bovine early embryo development

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2024年第4期15卷 1528-1549页

作者： Rosane Mazzarella Karina canon‑Beltran Yulia N.cajas Meriem Hamdi Encina M.Gonzalez Juliano c.da Silveira claudia l.V.leal D.Rizos Department of Animal Reproduction INIA-CSICMadridSpain Department of Biochemistry and Molecular Biology Veterinary FacultyComplutense University of Madrid(UCM)MadridSpain Department Agrarian Production Technical University of MadridUPMMadridSpain Departamento de ciencias Biologicas Universidad Tecnica Particular de LojaUTPLLojaEcuador Department of Anatomy and Embryology FV-UCMMadridSpain Department of Veterinary Medicine FZEA-USPPirassunungaBrazil

Background Extracellular vesicles(EVs) present in oviductal(OF) and uterine fluid(UF) have been shown to enhance bovine embryo quality during in vitro culture by reducing lipid contents and modulating lipid metabolism-related genes(lMGs), while also influencing cell proliferation, suggesting their involvement on the regulation of different biological pathways. The regulation of signaling pathways related to cell differentiation, proliferation, and metabo-lism is crucial for early embryo development and can determine the success or failure of the pregnancy. Bioactive molecules within EVs in maternal reproductive fluids, such as micro RNAs(miRNAs), may contribute to this regulatory process as they modulate gene expression through post-transcriptional *** This study evaluated miRNA cargo in OF-EVs from the early luteal phase and UF-EVs from the mid-luteal phase, coinciding with embryo transit within oviduct and uterus in vivo, and its possible influence on lMGs and sign-aling pathways crucial for early embryo development. A total of 333 miRNAs were detected, with 11 exclusive to OF, 59 to UF, and 263 were common between both groups. From the 20 differentially expressed miRNAs, 19 up-regulated in UF-EVs(bta-miR-134, bta-miR-151-3p, bta-miR-155, bta-miR-188, bta-miR-181b, bta-miR-181d, bta-miR-224, bta-miR-23b-3p, bta-miR-24-3p, bta-miR-27a-3p, bta-miR-29a, bta-miR-324, bta-miR-326, bta-miR-345-3p, bta-miR-410, bta-miR-652, bta-miR-677, bta-miR-873 and bta-miR-708) and one(bta-miR-148b) in OF-EVs. These miRNAs were predicted to modulate several pathways such as Wnt, Hippo, MAPK, and lipid metabolism and degradation. Differ-ences in miRNAs found in OF-EVs from the early luteal phase and UF-EVs from mid-luteal phase may reflect differ-ent environments to meet the changing needs of the embryo. Additionally, miRNAs may be involved, particularly in the uterus, in the regulation of embryo lipid metabolism, immune system, and *** Our study su

关键词： Embryo-maternal interaction Epigenetic Exosomes Mammalian Preimplantation Reproductive fluids

Effect of biochar on the metabolome of soybean seedlings

在线全文

学校读者我要写书评

暂无评论

Oil crop Science 2024年第1期9卷 60-68页

作者： Nathalia E.Silva Mariana G.Aguilar Osania E.Ferreira Gleicia M.Paulino Jaqueline c.l.carvalho lúcia P.S.Pimenta Alan R.T.Machado Programa de Pos-graduaçao em ciencias Ambientais Universidade do Estado de Minas GeraisFrutalMinas Gerais38202-436Brazil Departamento de Química Universidade Federal de Minas GeraisMinas GeraisBelo Horizonte31270-901Brazil Departamento de Engenharia Aplicada e Tecnologias Ambientais Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil Departamento de ciencias Exatas Universidade do Estado de Minas GeraisJoao MonlevadeMinas Gerais35930-314Brazil

The use of biochar can have several effects on plant germination,depending on raw material,preparation method and application ***,the molecular mechanisms that lead to those results have yet to be *** aim of this research was to improve the understanding of these mechanisms by characterizing the metabolic effects of sugarcane bagasse biochar on soybean *** types of biochars were prepared by pyrolysis at 300℃(ScB300),400℃(ScB400)and 600℃(ScB600).Then,each one was mixed into sand at 1%,3%,5%(w/w)dose,*** experiment was performed in 8 days of incubation,when the number of germinated seeds and the average radicle length were *** evaluate the metabolome,the dry biomass(DB)was subjected to extraction with a mixture of methanol-d4 and D2O(1:1 v/v).The extracts were submitted to metabolomics analysis by Proton Nuclear Magnetic *** Relative Germination,Relative Average Radicle Growth and Germination Index increased in all treatments compared to *** the other hand,the DB increased in all treatments,except for ScB300,at doses of 1%and 3%w/*** metabolites(alanine,asparagine,acetic acid,citric acid,glycerol,fatty acids and sucrose)were identified and quantified in DB extracts as the most influential finding for the separation of *** together,these results strongly suggested that biochars accelerated the catabolism of triacylglycerols to sucrose and induced a slight osmotic stress.

关键词： Germination Metabolomics 1H NMR Pyrolysis Sugarcane bagasse

corrosion testing of X52 and X80 steels immersed in stimulated emulsions using a real petroleum sample

在线全文

学校读者我要写书评

暂无评论

Petroleum Research 2024年第2期9卷 304-316页

作者： l.M.Quej-Ake J.l.Alamilla A.contreras Instituto Mexicano del Petróleo Eje Central Lázaro CárdenasNorte 152San Bartolo AtepehuacanGustavo A.MaderoCiudad de MéxicoC.P.07730México

The aim of this study is to evaluate the internal corrosion process on X52 and X80 steels/real petroleum interfaces containing condensed hydrocarbon plus oilfield-produced water,which were subjected to stimulated emulsions using 50/50 vol ratio mixtures at 45℃,different hydrodynamic conditions,1 h,and 24 h.A washing process by using deionized water was proposed to simulate and identify the corrosiveness of the hydrocarbon phase after 24 h of exposure *** characterization by electrochemical impedance spectroscopy and the monitoring of the polarization curves indicated that X80 steel/oilfield-produced water interfaces were more susceptible to corrosion than X52 steel exposed to oilfield-produced *** combined speed rotation of 600 rpm using a magnetic stirrer+600 rpm using a rotating disk electrode decreased the corrosion rate on X52 *** stimulated emulsions made of hydrocarbon+oilfield-produced water and hydrocarbon+deionized water at 24 h increased the corrosion rate on X80 steel(0.34 mm/year and 0.43 mm/year,respectively),promoting the formation of erosion and pitting *** types of corrosion depended mainly on the physicochemical properties of the hydrocarbon,oilfield-produced water,exposure times,and hydrodynamic systems in which the hydrocarbon was studied.

关键词： corrosion Emulsions X52 steel X80 steel

First-principles calculation on the electronic structures, phonon dynamics, and electrical conductivities of Pb_(10)(PO_(4))_(6O) and Pb_(9)cu(PO_(4))_(6O) compounds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第6期173卷 218-224页

作者： l.Y.Hao E.G.Fu State Key laboratory of Nuclear Physics and Technology Department of Technical PhysicsSchool of PhysicsPeking UniversityBeijing 100871China

Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power ***,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature *** 2023,a preprint by lee et *** South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in cu-doped lead-apatite(lK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and ***,the electronic structures,phonon dynamics,and electrical conductivities of lK-99 and its parent compound lead-apatite have been calculated using first-principles *** results show that the lead-apatite compound and the lK-99 compound are insulator and half-metal *** flat band characteristic is consistent with previous *** electrical conductivity of the lK-99 compound shows two extreme points,and the electrical conductivity along the c-axis increases significantly after 400 *** phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.

关键词： Superconductivity lK-99 lead-apatite First-principles calculation

Death from caustic ingestion:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Acute Disease 2024年第2期13卷 81-84页

作者： Shao Hui Koh Jacqueline c.l.Tan Department of Emergency Medicine Sengkang General HospitalSingapore

Rationale:Acute caustic ingestion from suicidal intent is not usual in emergency departments in developed *** of the substances commonly ingested by suicidal patients,phosphoric acid,tends to cause multi-system ***’s concern:A 41-year-old male patient presented with complaints of throat discomfort,severe generalized abdominal pain,and multiple episodes of hematemesis after ingesting a restroom cleaning ***:Poisoning by acute caustic ingestion(containingc acid andlene glycol).Interventions:The patient was administered 50 ml of 8.4%sodium bicarbonate solution followed by an isotonic sodium bicarbonate solution running at 500 ml/h,a hyperkalemia kit,ceftriaxone,metronidazole,omeprazole,and *** patient then underwent urgent ***:The patient suffered gastrointestinal bleeding as a result of local caustic *** addition,his course of illness was complicated by severe acidemia from high anion gap metabolic acidosis and deranged electrolytes(hyperphosphatemia,hyperkalemia,and hypocalcemia).He developed multi-organ failure and eventually ***:The clinician needs to be mindful of the multi-system complications arising from such a caustic *** patients need to be monitored closely for deterioration,and have prompt management of the various arising complications,to reduce the high morbidity and mortality associated with this condition.

关键词： Phosphoric acid poisoning caustic ingestion Acid ingestion cleaner ingestion corrosive ingestion