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Hydrogen transport in metals: integration of permeation, thermal desorption and degassing

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journal of Materials Science & Technology 2017年第12期33卷 1433-1447页

作者： E.i.Galindo-Nava b.i.Y.basha P.E.j.Rivera-Díaz-del-Castillo Department of Materials Science and Metallurgy University of Cambridge Department of Engineering Lancaster University

A modelling suite for hydrogen transport during electrochemical permeation, degassing and thermal desorption spectroscopy is presented. The approach is based on Fick＇s diffusion laws, where the initial concentration and diffusion coefficients depend on microstructure and charging conditions. The evolution equations are shown to reduce to classical models for hydrogen diffusion and thermal desorption spectroscopy. The number density of trapping sites is found to be proportional to the mean spacing of each microstructural feature, including dislocations, grain boundaries and various precipitates. The model is validated with several steel grades and polycrystalline nickel for a wide range of processing conditions and microstructures. A systematic study of the factors affecting hydrogen mobility in martensitic steels showed that dislocations control the effective diffusion coefficient of hydrogen. However,they also release hydrogen into the lattice more rapidly than other kind of traps. it is suggested that these effects contribute to the increased susceptibility to hydrogen embrittlement in martensitic and other high-strength steels. These results show that the methodology can be employed as a tool for alloy and process design, and that dislocation kinematics play a crucial role in such design.

关键词： Hydrogen Diffusion Modelling Trapping Permeation Desorption

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Acta Mechanica Sinica 2010年第4期26卷 567-572页

作者： D.j.Colquitt A.b.Movchan i.S.jones W.Daniels Department of Mathematical Sciences University of Liverpool School of Engineering John Moores University Serco Assurance Walton House 404 The QuadrantBirchwood ParkRisleyWarringtonCheshireWA3 6GAUK

The paper presents a computational model for elastic waves in a structured weld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of waves with the micro-structure of the weld. Effects of localisation and channeling of waves are addressed. A model of a grain structure within the weld is also considered.

关键词： Macro-structured welds Waves in stratified media Dispersion Localisation

Small extrachromosomal circular DNA in amyotrophic lateral sclerosis matter

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Neural Regeneration Research 2025年第5期20卷 1411-1413页

作者： Marcos j.Arauzo-bravo Daniela Gerovska Matthias Schwab Alexandra Kretz Computational biology and Systems biomedicine Biodonostia Health Research InstituteSan SebastianSpain basque Foundation for Science IKERBASQUEBilbaoSpainMax Planck Institute for Molecular BiomedicineComputational Biology and Bioinformatics GroupMünsterNorth Rhine-WestphaliaGermany Department of Cell biology and Histology Faculty of Medicine and NursingUniversity of Basque Country(UPV/EHU)LeioaSpain Department of Neurology Jena University HospitalJenaThuringiaGermany

Comprehensive studies identify motor neuron spectrum disorders including amyotrophic lateral sclerosis(ALS)as globally rising fatal disorders with the highest prevalence in aging populations,influenced by ethnicity and ancestry(GbD 2016 Motor Neuron Disease Colla borators,2018).While~10% of diagnoses involve a family history(fALS),most cases are considered sporadic(sALS).However,population-based studies suggest that even cases without a common index mutation impart heritability(Ryan et al.,2019),indicating a crucial role of rare and as yet unknown genetic denominators.

关键词： amyotrophic sclerosis

The price of protection:a defensive endosymbiont impairs nymph growth in the bird cherry-oat aphid,Rhopalosiphum padi

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insect Science 2020年第1期27卷 69-85页

作者： Daniel j.Leyboume jorunn i.b.bos Tracy A.Valentine Alison j.Karley Division of Plant Sciences School of Life SciencesUniversity of DundeeDundeeU K Cell and Molecular Sciences the James Hutton InstituteInvergowrieDundeeUK Ecological Sciences the James Hutton InstituteInvergowrieDundeeUK

bacterial endosymbionts have enabled aphids to adapt to a range of stressors,but their effects in many aphid species remain to be *** bird cherry-oat aphid,Rhopalosiphum padi(Linnaeus),is an important pest of cereals worldwide and has been reported to form symbiotic associations with Serratia symbiotica and Sitobion miscanthi L-type symbiont endobacteria,although the resulting aphid phenotype has not been *** study presents the first report of *** infection with the facultative bacterial endosymbiont Hamiltonella *** of *** were sampled from populations in Eastern Scotland,UK,and shown to represent seven *** genotypes based on the size of polymorphic microsatellite markers;two of these genotypes harbored *** parasitism assays,survival of ***-infected nymphs following attack by the parasitoid wasp Aphidius colemani(Viereck)was 5 fold higher than for uninfected *** genotype was a major determinant of aphid performance on two Hordeum species,a modern cultivar of barley *** and a wild relative ***,although aphids infected with *** showed 16%lower nymph mass gain on the partially resistant wild relative compared with uninfected *** findings suggest that deploying resistance traits in barley will favor the fittest *** genotypes,but symbiontinfected individuals will be favored when parasitoids are abundant,although these aphids will not achieve optimal performance on a poor quality host plant.

关键词： cereal aphid Hamiltonella defensa Hordeum spontaneum Hordeum vulgare symbiosis

Transverse approach between real world concentrations of SO_2, NO_2, bTEX, aldehyde emissions and corrosion in the Grand Mare tunnel

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journal of Environmental Sciences 2012年第7期24卷 1240-1250页

作者： i. Ameur-bouddabbous j. Kasperek A. barbier F. Harel b. Hannoyer GPM-UMR 6634 CNRS. UFR Science and Technology University of Rouen BP 12 76801 Saint Etienne du Rouvray Cedex France LCAE Chemistry Department Science Faculty of Tunis Campus Universitaire 2092 El Manar Tunis Tunisie DiRNO Rue de Verdun 76160 Darnetal France

With regard to automotive traffic, a tunnel-type semi enclosed atmosphere is characterized by a higher concentration of gaseous pollutants than on urban traffic roads and highlights the gaseous effluent species having an impact on material degradation. Therefore, a transverse approach between air quality and its consequences upon the longevity of materials is necessary, implying better knowledge of tunnel atmosphere and a better understanding of material degradation inside a tunnel for operating administration. Gaseous pollutant measurements carried out in a road tunnel in Rouen （Normandy） give the real world traffic concentrations of experimental exposure conditions. The sampling campaigns, achieved in summer and winter include SO2, NO2, bTEX and aldehyde analyses. Effluent profiles in the upward and downward tubes have been established. The current work shows that SO2, NO〉 formaldehyde, acetaldehyde, propanal and butanal must be considered in the degradation process of materials in a stuffy environment. As regards NO,, its concentration depends on the modification of the automotive fleet. The total aldehyde concentrations indicate no particular trend between the two bores. Formaldehyde, acetaldehyde, propanal, butanal and acrolein species are the most abundant species emitted by vehicles and represent 90% to 95% of the total aldehyde emissions.

关键词： SO2 tunnel study aldehydes NO2 bTEX atmospheric corrosion

GREEN bUiLDiNG MATERiALS:A REViEW OF STATE OF THE ART STUDiES OF iNNOVATiVE MATERiALS

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journal of Green building 2017年第4期12卷 141-161页

作者： P.De Luca i.Carbone j.b.Nagy Department of ingegneria per l’Ambiente ed il Territorio ed ingegneria Chimica University of CalabriaRendeItaly Department of ingegneria Civile University of CalabriaRendeItaly

***is paper presents a comprehensive survey of the latest international publications(2012-2017)regarding innovative and environmentally sustainable materials that reduce the production of *** is recognised that world construction is responsible for substantial amounts of harmful *** particular,the survey collected data on new sustainable solutions and innovative materials,such as cement,wood,glass and ceramics that are essential to minimize the environmental impact of buildings on the ecosystem and to reduce the consumption of natural resources.erefore,the paper’s intent is to give an overview of the current state of the art and research in theeld of bio-building,gathering information on the environmental impacts of these innovative materials and listing the benets that can be obtained with their *** findings of this study support the growing importance of grecn building as a componcnt of the whole construction market and provide a benchmark against which to mcasure futurc changes in the industry over time.

关键词： innovative materials sustainable materials bio-building green building

Numerical simulation on borehole breakout and borehole size effect using discrete element method

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international journal of Mining Science and Technology 2020年第5期30卷 623-633页

作者： H.Lin W.H.Kang j.Oh i.Canbulat b.Hebblewhite School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW 2052Australia Centre for infrastructure Engineering Western Sydney UniversityPenrithNSW 2751Australia

Estimation of horizontal stress magnitudes from borehole breakouts has been an attractive topic in the petroleum and mining industries,although there are critical research gaps that remain *** this paper,numerical simulation is conducted on Gosford sandstone to investigate the borehole breakout and its associated borehole size effect,including temperature *** discrete element method(DEM)model shows that the borehole breakout angular span is constant after the initial formation,whereas its depth propagates along the minimum horizontal stress *** indicates that the breakout angular span is a reliable parameter for horizontal stress *** borehole size effect simulations illustrated the importance of borehole size on breakout geometries in which smaller borehole size leads to higher breakout initiation stress as well as the stress re-distribution from borehole wall outwards through *** implies that the stress may be averaged over a distance around the borehole and breakout initiation occurs at the borehole wall rather than some distance into the *** addition,the numerical simulation incorporated the thermal effect which is widely encountered in deep geothermal *** on the results,the higher temperature led to lower breakout initiation stress with same borehole size,and more proportion of shear cracks was generated under higher *** indicates that the temperature might contribute to the micro-fracturing mode and hence influences the horizontal stress estimation results from borehole breakout *** simulation showed that breakout shape and dimensions changed considerably under high stress and high temperature conditions,suggesting that the temperature may need to be considered for breakout stress analysis in deep locations.

关键词： borehole breakout breakout angular span borehole size effect Numerical simulation Thermal effect

Degradation of Synthetic Dyeing Wastewater by Underwater Electrical Discharge Processes

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Plasma Science and Technology 2013年第7期15卷 659-665页

作者： S.D.KiM D.i.jANG b.j.LiM S.b.LEE Y.S.MOK Yeongsan River Environment Research Center National Institute of Environmental ResearchGwangju 500-480 Korea Department of Chemical and biological Engineering Jeju National UniversityJeju 690-756 Korea

Electrical discharge treatments of synthetic dyeing wastewater were carried out with two different systems： underwater pulsed electrical discharge （UPED） and underwater dielectric barrier discharge （UDbD）. Reactive blue 4 （Rb4） and Acid Red 4 （AR4） were used as model contaminants for the synthetic wastewater. The performance of the aforementioned systems was compared with respect to the chromaticity removal and the energy requirement. The results showed that the present electrical discharge systems were very effective for degradation of the dyes. The dependences of the dye degradation rate on treatment time, initial dye concentration, electrical energy, and the type of working gas including air, 02, and N2 were examined. The change in the initial dye concentration did not largely affect the degradation of either Rb4 or AR4. The energy delivered to the UPED system was only partially utilized for generating reactive species capable of degrading the dyes, leading to higher energy requirement than the UDbD system. Among the working gases, the best performance was observed with O2. As the degradation proceeded, the concentration of total dissolved solids and the solution conductivity kept increasing while pH showed a decreasing trend, revealing that the dyes were effectively mineralized.

关键词： degradation dyeing wastewater pulsed electrical discharge dielectric barrierdischarge

Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： byeongchan Ahn Sua jo jonggeol Na j.jay Liu Young-ju Kim Wangyun Won Department of Chemical and biological Engineering Korea University Department of Chemical Engineering (integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy b, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Carbon capture and utilization