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Simulation of mass balance behavior in a large-scale circulating fluidized bed reactor

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Particuology 2016年第2期14卷 51-58页

作者： Artur Blaszczuk anna Zylka Jacek Leszczynski Czestochowa University of Technology Institute of Advanced Energy Technologies Dabrowskiego 73 42-200 Czestochowa Poland AGH University Science and Technology Faculty of Energy and Fuels Department of Hydrogen Energy Mickiewicza 30 30-059 Cracow Poland

We determine using a compound model the influence of the mass of granular matter on the behavior of a supercritical circulating fluidized bed （CFB） reactor. Population balance enables a stationary-regime modeling of the mass flow of granular matter inside a CFB unit in a large-scale. The simulation includes some important dynamic processes of gas-particle flows in fluidized bed such as attrition, fragmenta- tion, elutriation, and fuel combustion. Numerical calculations with full boiler loading were performed of operational parameters such as furnace temperature, furnace pressure, feeding materials mass flows, and excess air ratio. Furthermore, three bed inventory masses were adopted as experimental variables in the simulation model of mass balance. This approach enables a sensitivity study of mass flows of granular matter inside a CFB facility. Some computational results from this population balance model obtained for a supercritical CFB reactor are presented that show consistency with the operational data for large-scale CFB units.

关键词： Bed inventory mass Mass flow of solids Circulating fluidized bed Population mass balance mode Sensitivity analysis

Surface coal mine permit application for successful reclamation, semi-arid shortgrass prairie （Wyoming, USA）

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International Journal of Coal Science & Technology 2018年第1期5卷 8-17页

作者： anna Krzyszowska Waitkus Environmental Consulting 80 Eagle Nest LaramieWY 82070 USA

Approximately 40% of USA coal originates in an ecologically sensitive area of semi-arid shortgrass prairie in Wyoming. Before a surface coal mine can begin operation in the USA, it must secure a mining permit and comply with regulations and performance standards under the USA Surface Mining Control and Reclamation Act （SMCRA）, other federal environmental acts, and state programs. The Wyoming Department of Environmental Quality （WDEQ）/Land Quality Division （LQD） administers Wyoming＇s coal regulatory program. The permit application and bonding process for the largest surface coal mine permit in the USA, North Antelope Rochelle Mine （NARM） located in short grassland prairie in the northeast Wyoming, is discussed. The permit application process begins with the collection of baseline environ- mental data that characterizes premining conditions of the permit area. The permit application includes adjudication information, baseline information, mine and operation plans, and reclamation plans. Fulfillment of permit commitments and requirements of rules and regulations are inspected monthly by the LQD＇ s representative in the field. Before a mine permit is issued, the mine operator must submit a reclamation bond to secure the performance of reclamation obligations that is later revised annually. In Wyoming, four reclamation bond release phases indicate the completion of various stages of the reclamatikon process. NARM＇s specific bond release verification cirteria, performance standards, and field verificatoins of bond release phases are discussed. The Bond Release Geodatabase （a GIS/GPS approach） was developed for this mine to monitor progress in meeting criteria and performance standards for incremental bond release. The Bond Release Geodatabase significantly reduces the time needed to track bond release progress, reach agreement between operator and regulator, and improve the state inspector＇s ability to assess reclamation adequacy and progress.

关键词： Surface coal mine permitting Bonding Reclamation GIS/GPS geodatabase USA rules and regulations Inspections

Experimental analysis of ballistic trauma in a human body protected with 30 layer packages made of biaxial and triaxial Kevlar^(■)29 fabrics

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Defence Technology（防务技术） 2023年第3期21卷 73-87页

作者： Justyna Pinkos Zbigniew Stempien anna Smędra Institute of Textile Architecture Lodz University of TechnologyLodzPoland Chair and Department of Forensic Medicine Medical University of LodzLodzPoland

Behind armour blunt trauma(BABT)is a body injury resulting from the deformation of the back surface of armour as a result of a bullet *** the case of textile body armour,the severity of the injury may depend on the material of the fibres,but also on the geometric structure of the *** article focuses on experimental research into injuries of the human body protected by ballistic packets made of biaxial and triaxial fabrics,during a non-penetrating impact from a Parabellum 9 mm×19 mm Full Metal Jacket(FMJ)bullet,at a speed of 406±5 m/*** experimental research,the fabrics had a comparable surface weight and were made of the same Kevlar^(■)29 *** ballistic packages were made of 30 *** part of the work,a physical model of the human body was *** human body model consisted of a model of the heart,lungs,and skeletal and muscular *** the bullet impact,the pressure forces were recorded using sensors located at selected points of the human *** bullets hit five selected places on the body that were considered critical,from the point of view of maintaining a human’s vital *** was found that,during firing,pressure increases both at the site of impact and in the internal organs,which can lead to multi-organ *** a result of the experimental analysis,it has been shown that the pressures exerted on specific organs are always lower in the case of body protection with a ballistic packet made of triaxial fabrics,compared to a packet made of biaxial fabrics.

关键词： protected impact organs

Stem cells, a two-edged sword: Risks and potentials of regenerative medicine

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World Journal of Gastroenterology 2008年第27期14卷 4273-4279页

作者： anna Chiara Piscaglia Department of Internal Medicine and Gastroenterology "GI & Liver Stem Cell Research Group" Catholic University of Rome

The recent advancements in stem cell (SC) biology have led to the concept of regenerative medicine, which is based on the potential of SC for therapies aimed to facilitate the repair of degenerating or injured tissues. Nonetheless, prior to large scale clinical appli- cations, critical aspects need to be further addressed, including the long-term safety, tolerability, and efficacy of SC-based treatments. Most problematic among the risks of SC-based therapies, in addition to the pos- sible rejection or loss of function of the infused cells, is their potential neoplastic transformation. Indeed, SCs may be used to cure devastating diseases, but their specific properties of self-renewal and clonogenicity may render them prone to generate cancers. In this respect, ‘Stemness’ might be seen as a two-edged sword, its bright side being represented by normal SCs, its dark side by cancer SCs. A better understand- ing of SC biology will help fulfill the promise of regen- erative medicine aimed at curing human pathologies and fighting cancer from its roots.

关键词： Stem cells Regenerative medicine Gastrointestinal diseases Chronic liver diseases Cell-basedtherapy

Predetermination of potential plastic hinges on reinforced concrete frames using GFRP reinforcement

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Frontiers of Structural and Civil Engineering 2022年第5期16卷 624-637页

作者： Dominik KUERES Dritan TOPUZI Maria anna POLAK Department of Civil and Environmental Engineering University of WaterlooWaterlooON N2L 3G1Canada Schoeck Canada Inc. OttawaON K1P 5G3Canada

In the past,glass fiber-reinforced polymer(GFRP)-reinforcement has been successfully applied in reinforced concrete(RC)structures where corrosion resistance,electromagnetic neutrality,or cuttability were *** investigations suggest that the application of GFRP in RC structures could be advantageous in areas with seismic activity due to their high deformability and ***,especially the low modulus of elasticity of GFRP limited its wide application as GFRP-reinforced members usually exhibit considerably larger deformations under service loads than comparable steel-reinforced *** overcome the aforementioned issues,the combination of steel and GFRP reinforcement in hybrid RC sections has been investigated in the *** on this idea,this paper presents a novel concept for the predetermination of potential plastic hinges in RC frames using GFRP *** analyze the efficiency of the concept,nonlinear finite element simulations were *** results underscore the high efficiency of hybrid steel-GFRP RC sections for predetermining potential plastic hinges on RC *** results also indicate that the overall seismic behavior of RC structures could be improved by means of GFRP as both the column base shear force during the seismic activity as well as the plastic deformations after the earthquake were considerably less pronounced than in the steel-reinforced reference structure.

关键词： glass fiber-reinforced polymer GFRP hybrid section plastic hinge seismic design reinforced concrete

焊接速度及芯环比对热成形钢双光斑激光焊接接头组织与性能的影响

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精密成形工程 2024年第8期16卷 155-164页

作者：张婧珂刘岩杜安娜张文广沈阳大学机械工程学院沈阳110044 辽宁省先进材料制备技术重点实验室沈阳110044

目的研究焊接速度和芯环比对PHS2000热成形钢双光斑激光焊接接头组织与性能的影响。方法使用光学显微镜(OM)、扫描电子显微镜(SEM)等分析了不同参数下焊接接头的组织演变过程,并对焊接接头的抗拉强度和显微硬度进行了测量对比。结果随... 详细信息

目的研究焊接速度和芯环比对PHS2000热成形钢双光斑激光焊接接头组织与性能的影响。方法使用光学显微镜(OM)、扫描电子显微镜(SEM)等分析了不同参数下焊接接头的组织演变过程,并对焊接接头的抗拉强度和显微硬度进行了测量对比。结果随着焊接速度的增大,焊缝区(Weld Zone,WZ)平均晶粒尺寸由12.33μm逐渐减小至10.52μm。热影响区(HeatAffectedZone,HAZ)平均晶粒尺寸由11.37μm逐渐减小至9.12μm。随着芯环比的提高,WZ平均晶粒尺寸由11.13μm增加至12.62μm;其中,当芯环比为65%时,HAZ平均晶粒尺寸最小,为9.66μm。随着焊接速度和芯环比的提高,焊接接头处的抗拉强度大致呈先上升后下降的趋势。当焊接速度为150mm/min和芯环比为65%时,焊缝区的显微硬度普遍高于其他参数下焊缝区的显微硬度。结论与芯环比相比,焊接速度对焊接接头组织和力学性能的影响较大;在固定激光功率为4100 W、离焦量为–2 mm的情况下,当焊接速度为150 mm/min、芯环比为65%时,焊接接头的抗拉强度最优,达到1715MPa。

关键词：双光斑激光器 PHS2000热成形钢显微组织力学性能工艺参数

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论健康码的法律属性

中国卫生法制 2024年第1期32卷 9-14页

作者：刘宗胜蒋安娜湘潭大学信用风险管理学院湖南湘潭市411100

在新冠疫情防控背景下,“健康码”的诞生正是数字时代的产物,为政府提高政务诚信建设提供了有力的支撑点。健康码运行机理分为申请、生成、应用三个阶段。在法律属性上,健康码的申请是一种行政许可,健康码的生成是一种行政裁量,健康码... 详细信息

在新冠疫情防控背景下,“健康码”的诞生正是数字时代的产物,为政府提高政务诚信建设提供了有力的支撑点。健康码运行机理分为申请、生成、应用三个阶段。在法律属性上,健康码的申请是一种行政许可,健康码的生成是一种行政裁量,健康码的应用是一种行政强制,但从健康码运行的全流程来看,它是一种自动化行政辅助决策行为。公民对健康码申请、生成、应用的异议均具有行政可诉性,为公众后续合法权益受损提供更广阔的救济途径。

关键词：健康码法律属性行政可诉性

A critical review of national physical activity policies relating to children and young people in England

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Journal of Sport and Health Science 2021年第3期10卷 255-262,F0003页

作者： anna Chalkley Karen Milton School of Sport Exercise and Health SciencesLoughborough UniversityLoughborough LE113TUUK Norwich Medical School University of East AngliaNorwich NR47TJUK

Background:There has been an increasing focus on the importance of national policy to address population levels of physical *** has been suggested that the 4 cornerstones of policy comprise(1)national guidelines on physical activity(PA),(2)setting population goals and targets,(3)surveillance or health-monitoring systems,and(4)public *** current study aimed to review the policy actions that have addressed each of these elements for children and youth in England and to identify areas of progress and remaining ***:A literature search was undertaken to identify past and present documents relevant to PA policy for children and youth in *** document was analyzed to identify content relevant to the 4 cornerstones of ***:Physical activity guidelines(Cornerstone 1)for children and youth have been in place since 1998 and reviewed *** activity targets(Cornerstone 2)have focussed on the provision of opportunities for PA,mainly through physical education in schools rather than in relation to the proportion of children meeting recommended PA *** has been much surveillance(Cornerstone 3)of children’s PA,but this has been undertaken infrequently over time and with varying inclusions of differing domains of *** has been only 1 campaign(Cornerstone 4)that targeted children and their intermediaries,Change4Life,which was an obesity campaign focussing on dietary behavior in combination with *** recently,a government infographic supporting the PA guidelines for children and young people was developed,but details of its dissemination and usage are ***:There have been many developments in national PA policy in England targeted to children and young *** area of most significant progress is national PA *** prevalence targets,streamlining surveillance systems,and investing in public education with supportive policies,environments,and opportunities would st

关键词： Physical activity Policy Public education Recommendations Surveillance

Nonlinear interference in crystal superlattices

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Light(Science & Applications) 2020年第1期9卷 1239-1245页

作者： anna V.Paterova Leonid A.Krivitsky Institute of Materials Research and Engineering(IMRE) Agency for Science Technology and Research(A*STAR)138634 SingaporeSingapore

Nonlinear interferometers with correlated photons hold promise to advance optical characterization and metrology techniques by improving their performance and *** interferometers offer subshot noise phase sensitivity and enable measurements in detection-challenging regions using inexpensive and efficient *** sensitivity of nonlinear interferometers,defined by the ability to measure small shifts of interference fringes,can be significantly enhanced by using multiple nonlinear elements,or crystal ***,to date,experiments with more than two nonlinear elements have not been realized,thus hindering the potential of nonlinear ***,we build a nonlinear interferometer with up to five nonlinear elements,referred to as superlattices,in a highly stable and versatile *** study the modification of the interference pattern for different configurations of the superlattices and perform a proof-of-concept gas sensing experiment with enhanced *** approach offers a viable path towards broader adoption of nonlinear interferometers with correlated photons for imaging,interferometry,and spectroscopy.

关键词： spectroscopy nonlinear Nonlinear