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Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−Noyce−Shockley recombination mechanism

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Journal of Semiconductors 2024年第8期45卷 25-33页

作者： Fedor i.Manyakhin Dmitry O.Varlamov Vladimir P.Krylov Lyudmila O.Morketsova Arkady A.Skvortsov Vladimir K.Nikolaev Dinamics Strength of Machines and Resisance of MaterialsMoscow Polytechnic UniversityRussia Biomedical and Electronic Means and Technologies Vladimir State UniversityRussia Computer-Aided Design and Engineering National University of Science and Technology"MISiS"Russia

Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their *** technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.

关键词： light-emitting diodes with quantum wells voltage−current relation nonideality factor recombination mechanism Sah−Noyce−Shockley model

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interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita i.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova Sergey V.Dmitriev Research Laboratory for Metals and Alloys under Extreme impacts Ufa University of Science and Technology institute for Metals Superplasticity Problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University institute of Mechanical Science Problems of RAS institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations Voids Boundary conditions

influence of donor age on liver transplantation outcomes: A multivariate analysis and comparative study

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 331-344页

作者： Miran Bezjak ivan Stresec Branislav Kocman Stipislav Jadrijević Tajana Filipec Kanizaj Miro Antonijević Bojana Dalbelo Bašić Danko Mikulić Department of Surgery University Hospital MerkurZagreb 10000Croatia Department of Electronics MicroelectronicsComputer and Intelligent SystemsFaculty of Electrical Engineering and ComputingZagreb 10000Croatia Department of Gastroenterology University Hospital MerkurZagreb 10000Croatia Development of Software Nanobit Ltd.Zagreb 10000Croatia

BACKGROUND The growing disparity between the rising demand for liver transplantation(LT)and the limited availability of donor organs has prompted a greater reliance on older liver ***,utilizing livers from elderly donors has been associated with outcomes inferior to those achieved with grafts from younger *** accounting for additional risk factors,we hypothesize that the utili-zation of older liver grafts has a relatively minor impact on both patient survival and graft *** To evaluate the impact of donor age on LT outcomes using multivariate analysis and comparing young and elderly donor *** in the period from April 2013 to December 2018,656 adult liver transplants were performed at the University Hospital *** multivariate Cox propor-tional hazards models were developed to independently assess the significance of donor *** age was treated as a continuous *** approach involved univariate and multivariate analysis,including variable selection and assessment of interactions and ***,to exemplify the similarity of using young and old donor liver grafts,the group of 87 recipients of elderly donor liver grafts(≥75 years)was compared to a group of 124 recipients of young liver grafts(≤45 years)from the *** rates of the two groups were estimated using the Kaplan-Meier method and the log-rank test was used to test the differences between *** Using multivariate Cox analysis,we found no statistical significance in the role of donor age within the constructed *** when retained during the entire model development,the donor age's impact on survival remained insignificant and transformations and interactions yielded no substantial effects on *** insigni-ficance and low coefficient values suggest that donor age does not impact patient survival in our ***,there was no statistical evidence that the five developed models did not adhe

关键词： Liver transplantation Elderly donors Survival analysis Postoperative complications Cox proportional hazard models

Genotypic effects on accelerated propagation of oil palm breeding materials selected(Elaeis guineensis jacq.)using somatic embryogenesis

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Oil Crop Science 2024年第2期9卷 111-120页

作者： Retno Puji Astari Mohammad Basyuni Luthfi A.M. Siregar Revandy i.M. Damanike Deni Arifiyanto Dadang Affandi indra Syahputra Doctoral Program of Agricultural Sciences Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia PT.Socfin indonesia Jl.K.L.Yos Sudarso No.106Medan20244North SumatraIndonesia Department of Forestry Faculty of ForestryUniversitas Sumatera UtaraJl.Tri Dharma Ujung No.1Medan20155North SumatraIndonesia Center of Excellence for Mangrove Universitas Sumatera UtaraMedan20155Indonesia Department of Agrotechnology Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia

Vegetable oil production from oil palm(Elaeis guineensis Jacq.)is an important industry due to the rising demand every *** somatic embryogenesis culture can propagate oil palm duplicate as parent plant,which can be selected as breeding material to produce new planting germplasm with high production or disease *** study aims to evaluate the genotypic effect of somatic embryogenesis,while immature leaflets were employed as *** culture used embryo induction medium based on Murashige and Skoog(MS)modifications that contained 5 mg/L Naphthalene Acetic acid(NAA)and 0.5 mg/L Benzyl Amino Purine(BAP).The genotypic effect was statistically significant in the percentage of callus induction,producing somatic embryos,and germination *** this study,we successfully cloned thirteen oil palm genotypes(GE-02,GE-03,GE-06,GE-07,GE-09,GE-23,GE-24,GE-27,GE-28,GE-32,GE-33,GE-34,and GE-35),with the highest number of somatic embryos formed on GE-27 with a percentage of 70.1%.The cloning was successful in accelerating the propagation of oil palm for materials breeding programs to create new varieties with high production and disease *** is necessary to observation the performance of these clones in the field in terms of mantle flower appearance.

关键词： Somatic embryogenesis Oil palm Genotypic effect Support breeding

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Exploring the impact of tacrolimus on kidney transplant recipients: insights into immunological outcomes

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Journal of Chinese Pharmaceutical Sciences 2024年第8期 737-750页

作者： Zainab A Abbood Ahmed Hamza AL-Shammari Eman M.Jasim Amjad i.Oraibi Department of Pharmacy Kut University College AL-Manara College For Medical Science/Department of Pharmacy

To minimize graft rejection, it is crucial to reduce immunosuppression. in the present study, we investigated immunological markers in the blood of transplant patients who did not receive tacrolimus. We also assessed alloreactive CD4+CD25+Fox P3+ Tregs both before transplantation and after tacrolimus reduction. The comparative analysis included 50 individuals experiencing early rejection after tacrolimus discontinuation and 100 non-rejectors. Before reducing tacrolimus, rejectors exhibited elevated levels of memory CD8+ T cells compared to Tregs, while non-rejectors displayed a lower ratio of memory CD4+ T cells to Tregs. Following tacrolimus removal, rejectors showed an increase in na?ve T cells and a decrease in effector T cells. After transplantation, CD4+ Treg levels declined, but their anti-donor regulatory function remained consistent in both rejectors and non-rejectors. immunological correlation revealed an association between acute rejection after tacrolimus discontinuation and the pre-reduction ratio of memory T cells to regulatory T cells. These indicators identified individuals whose immunosuppression could be safely reduced.

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Monitoring the transformation in New Cairo’s urban vitality and the accompanying social and economic phenomena

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Frontiers of Architectural Research 2023年第5期12卷 867-891页

作者： Tamir El-Khouly asmaa Eldiasty Basil Kamel Department of Architecture Faculty of EngineeringAin Shams UniversityCairo 11566Egypt Department of Architecture School of Sciences and EngineeringThe American University in CairoCairo 11835Egypt Department of Architecture Faculty of EngineeringHorus UniversityNew Damietta 34517Egypt

Many cities in Egypt have been built recently with spatial characteristics that differ structurally from the spatial configuration of the ancient Arab *** is a growing interest in understanding how social and economic phenomena related to the community are transformed in new cities,particularly those that extend from the old city,as is the case with the city of New *** have developed an analytical framework to study the effects of spatial configuration on the pace of growth of the new city and identify its characteristics in terms of phenomena related to movement and the distribution of economic activities,as well as urban vitality.A framework for combining quantitative and qualitative analysis helps in understanding phenomena related to the morphology of the development of the new *** syntactic analysis,place syntax and field observation,the spatial characteristics of the city of New Cairo were investigated,then compared with Old Cairo to determine which features were enriched in terms of the city’s vitality or what has been lost during the expansion phases,based on the planning concepts that were *** study concluded that changes in the characteristics of the spatial configurations of the new Egyptian cities by increasing the flow of vehicular traffic via wide arterial roads do not reflect the requirements of the local community,but instead impede local movement within the city and reduce the integration of its neighbourhoods,turning them into isolated *** greatest impact of this is the way in which the characteristics of society in these cities have been limited,resulting in isolation and a lack of connection with the identity of the place and the customs and traditions of the *** paper presents an analytical framework for evaluating similar cities in terms of the characteristics of this planning configuration,identifying the extent to which the old has been preserved or changed and emphasising the validity of the meth

关键词： Space syntax Naturalmovement Spatial configuration Urban vitality

Scheduling Multi-Mode Resource-Constrained Projects Using Heuristic Rules Under Uncertainty Environment

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Computers, Materials & Continua 2022年第1期70卷 847-874页

作者： Mohamed Abdel-Basset Ahmed Sleem asmaa Atef Yunyoung Nam Mohamed Abouhawwash Faculty of Computers and informatics Zagazig UniversityZagazig44519Egypt Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA

Project scheduling is a key objective of many models and is the proposed method for project planning and *** scheduling problems depend on precedence relationships and resource constraints,in addition to some other limitations for achieving a subset of *** scheduling problems are dependent on many limitations,including limitations of precedence relationships,resource constraints,and some other limitations for achieving a subset of *** project scheduling models consider all information about the scheduling problem such as activity durations and precedence relationships information resources available and required,which are known and stable during the implementation *** concept of deterministic project scheduling conflicts with real situations,in which in many cases,some data on the activity’s durations of the project and the degree of availability of resources change or may have different modes and strategies during the process of project implementation for dealing with multi-mode conditions surrounded by projects and their activity *** the multi-mode resource-constrained project problem is an optimization problem whose minimum project duration subject to the availability of resources is of particular interest to *** use the multi-mode resource allocation and schedulingmodel that takes into account the dynamicity features of all parameters,that is,the scheduling process must be flexible to dynamic environment *** this paper,we propose five priority heuristic rules for scheduling multi-mode resource-constrained projects under dynamicity features for more realistic situations,in which we apply the proposed heuristic rules(PHR)for scheduling multi-mode resource-constrained *** projects are considered test problems for the *** obtained results rendered by these priority rules for the test problems are compared by the results obtained from 10 well-known heuristics rules rendered for

关键词： Constrained resource scheduling multi-mode durations dynamic scheduling resource allocation heuristic rules

Experimental test of a building thermal system for preventive maintenance based on thermoeconomic analysis

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Energy Storage and Saving 2024年第1期3卷 42-51页

作者： i.Prol-Godoy A.Picallo-Perez J.M.Sala-Lizarraga J.Rey-Martínez Research group ENEDi Department of Thermal EngineeringUniversity of the Basque Country(UPV/EHU)Bilbao48013Spain Research Group Termotecnia University of ValladolidValladolid47002Spain

An analysis of the sectorial structure of energy consumption shows that residential and tertiary sector buildings are the third-highest consumers,responsible for 29.5%of a city’s final energy *** Building Quality Control Laboratory of the Basque Government aims to promote quality,innovation,and sustainability in *** accomplish this goal,it has constructed an experimental facility with different energy generation technologies and a very versatile control system for testing different energy systems and operation *** this study,we tested a facility for supplying domestic hot water and heating for a multi-family house by means of a condensing boiler and an aerothermal heat pump(together with the corresponding control).This installation could reproduce the thermal demands required to be satisfied by the generation equipment through a programmed operation of the installation based on real ***,this installation was analyzed using thermoeconomics(TE)to solve problems unable to be solved using traditional energy analyses based on the First Law of *** problems include:(1)Determining the costs of the products of the installation based on physical criteria,(2)detecting the places where losses actually occur,evaluating their costs,and proposing cost-effective improvements,and(3)diagnosing issues in the *** a result,this paper suggests a solution to the preventive maintenance problems confronting the technical maintenance personnel for thermal installations in buildings by applying TE knowledge and using real data collected from sensors.

关键词： Experimental essay Energy savings in thermal systems Thermoeconomics Thermoeconomic costs Diagnosis

Multi-Pollutant Formation and Control in Pressurized Oxy-Combustion:SO_(x),NO_(x),Particulate Matter,and Mercury

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Engineering 2024年第8期39卷 127-153页

作者： Gaofeng Dai Jiaye Zhang Zia ur Rahman Yufeng Zhang Yili Zhang Milan Vujanović Hrvoje Mikulčić Nebojsa Manic Aneta Magdziarz Houzhang Tan Richard L.Axelbaum Xuebin Wang MOE Key Laboratory of Thermo-Fluid Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Ecology and Environment Hainan UniversityHaikou 570228China Faculty of Mechanical Engineering&Naval Architecture University of ZagrebZagreb 10000Croatia Faculty of Mechanical Engineering University of MariborMaribor 2000Slovenia Faculty of Mechanical Engineering University of BelgradeBelgrade 11120Serbia AGH University of Krakow Krakow 30059Poland Consortium for Clean Coal Utilization Department of EnergyEnvironmental&Chemical EngineeringWashington University in St.LouisSt.LouisMO 63130USA

Oxy-combustion is a promising carbon-capture technology,but atmospheric-pressure oxy-combustion has a relatively low net efficiency,limiting its application in power *** pressurized oxycombustion(POC),the boiler,air separation unit,flue gas recirculation unit,and CO_(2)purification and compression unit are all operated at elevated pressure;this makes the process more efficient,with many advantages over atmospheric pressure,such as low NO_(x)emissions,a smaller boiler size,and *** is also more promising for industrial application and has attracted widespread research interest in recent *** can produce high-pressure CO_(2)with a purity of approximately 95%,which can be used directly for enhanced oil recovery or ***,the pollutant emissions must meet the standards for carbon capture,storage,and *** of the high oxygen and moisture concentrations in POC,the formation of acids via the oxidation and solution of SO_(x)and NO_(x)can be increased,causing the corrosion of pipelines and ***,particulate matter(PM)and mercury emissions can harm the environment and human *** main distinction between pressurized and atmospheric-pressure oxy-combustion is the former’s elevated pressure;thus,the effect of this pressure on the pollutants emitted from POC—including SO_(x),NO_(x),PM,and mercury—must be understood,and effective control methodologies must be incorporated to control the formation of these *** paper reviews recent advances in research on SO_(x),NO_(x),PM,and mercury formation and control in POC systems that can aid in pollutant control in such systems.

关键词： Pressurized oxy-combustion Sulfur oxides Nitrogen oxides Particulate matter Mercury Direct contact cooler Carbon capture and sequestration