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Effect of rock joints on lined rock caverns subjected to high internal gaspressure

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1625-1635页

作者： Davi Rodrigues Damasceno johan Spross Fredrik johansson Division of Soil and Rock Mechanics KTH Royal Institute of TechnologySE-10044StockholmSweden

The storage of hydrogen gas in lined rock caverns(LRCs)may enable the implementation of the firstlarge-scale fossil-free steelmaking process in Sweden,but filling such storage causes joints in the rockmass to open,concentrating strains in the *** structural interaction between the LRC componentsmust be able to reduce the strain concentration in the sealing steel lining;however,this interaction iscomplex and difficult to predict with analytical *** this paper,the strain concentration in LRCsfrom the opening of rock joints is studied using finite element(FE)analyses,where the large-and small-scale deformation behaviors of the LRC are *** model also includes concrete crack initiation anddevelopment with increasing gas pressure and rock joint *** interaction between the jointed rockmass and the reinforced concrete,the sliding layer,and the steel lining is *** results showthat the rock mass quality and the spacing of the rock joints have the greatest influence on the straindistributions in the steel *** largest effect of rock joints on the maximum strains in the steellining was observed for geological conditions of“good”quality rock masses.

关键词： Lined rock cavern(LRC) Rock joints Strain concentrations Lining interaction Finite element(FE)analysis High gas pressure

Postprandial triglyceride metabolism in elderly men with subnormal testosterone levels

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Asian Journal of Andrology 2008年第4期10卷 542-549页

作者： Ingvild Agledahl John-Bjarne Hansen johan Svartberg Department of Medicine University Hospital of North Norway TromsO 9038 Norway Center for Atherothrombotic Research in TromsФ （CART） Institute of Clinical Medicine University of TromsФ TromsФ 9037 Norway institute of Clinical Medicine University of TromsФ TromsФ 9037 Norway

Aim： To investigate the level of postprandial triglycerides （TG）s in elderly men with subnormal testosterone level （≤ 11.0 nmol/L） compared to men with normal testosterone level （〉 11.0 nmol/L）. Methods： Thirthy-seven men with subnormal and 41 men with normal testosterone aged 60-80 years underwent an oral fat load and TG levels were measured fasting and 2, 4, 6 and 8 h afterwards. Results： Men with subnormal testosterone had significantly higher body mass index （BMI） and waist circumference （P 〈 0.001） than men with normal testosterone. They had significantly higher area under curve （AUC, P = 0.037）, incremental area under curve （AUCi, P = 0.035） and TG response （TGR, P = 0.014） for serum-TG and significantly higher AUC （P = 0.023）, AUCi （P = 0.023） and TGR （P = 0.014） for chylomicron-TG compared to men with normal testosterone level. Adjusting for waist circumference erased the significant differences between the groups in postprandial triglyceridemia. Conclusion： Men with subnormal testosterone have increased postprandial TG levels indicating an impaired metabolism of postprandial TG-rich lipoproteins （TRL）, which may add to an unfavourable lipid profile and promote development of atherosclerosis.

关键词： testosterone sex hormone-binding globulin postprandial triglycerides abdominal obesity waist circumference

Isolation of Thermally Stable Cellulose Nanocrystals from Spent Coffee Grounds via Phosphoric Acid Hydrolysis

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Journal of Renewable Materials 2020年第2期8卷 187-203页

作者： Brody A.Frost E.johan Foster Virginia Tech Department of Materials Science and EngineeringMacromolecules Innovation Institute117 SurgeVirginia TechBlacksburgVA 24061USA

As the world's population exponentially grows,so does the need for the production of food,with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few *** rapid growth in food production results in an ever increasing amount of agricultural wastes,of which already occupies nearly 50%of the total landfill *** example,is the billions of dry tons of cellulose-containing spent coffee grounds disposed in landfills *** paper seeks to provide a method for isolating cellulose nanocrystals(CNCs)from spent coffee grounds,in order to recycle and utilize the cellulosic waste material which would otherwise have no *** have already been shown to have vast applications in the polymer engineering field,mainly utilized for their high strength to weight ratio for reinforcement of polymer-based nanocomposites.A successful method of purifying and hydrolyzing the spent coffee grounds in order to isolate usable CNCs was *** CNCs were then characterized using current techniques to determine important chemical and physical properties.A few crucial properties determined were aspect ratio of 12±3,crystallinity of 74.2%,surface charge density of(48.4±6.2)mM/kg cellulose,and the ability to successfully reinforce a polymer based *** characteristics compare well to other literature data and common commercial sources of CNCs.

关键词： Cellulose nanocrystals phosphoric acid hydrolysis agricultural waste industrial waste spent coffee grounds polymeric nanocomposites renewable cellulosic materials

Mycelium as a self-growing biobased material for the fabrication of single-layer masks

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Journal of Bioresources and Bioproducts 2023年第4期8卷 399-407页

作者： Victoria French Chuanshen Du E.johan Foster Department of Chemical and Biological Engineering Vancouver Bioproducts InstituteUniversity of British ColumbiaVancouverBCV6T 1Z3Canada

Disposable face masks are an essential piece of personal protective equipment for workers in medical facilities,laboratories,and the general public to prevent the spread of illnesses and/or ***-19 resulted in an uptick in the usage and production of face masks,exacerbating issues related to the waste and recycling of these ***,face masks are derived from petrochemicals,such as melt-blown or spunbound *** such,there is a need to find sustainable mask materials that can maintain or improve the performance of petrochemical *** paper explores an alternative mask material that utilizes fungal mycelium as self-growing filaments to enhance the efficiency of individual polypropylene mask *** engineering the growth pattern and time,breathability and filtration efficiency was optimized such that one layer of the mycelium-modified mask could replace all three layers of the traditional three-layer ***,it was found that the mycelium-modified mask exhibits asymmetric hydrophobicity,with super-hydrophobicity at the composite-air interface and lower hydrophobicity at the composite-medium *** property can improve the performance of the modified mask by protecting the mask from external liquids without trapping water vapor from the user’s *** findings from this study can provide a basis for further development of mycelium to create sustainable filtration materials with enhanced functionality.

关键词： Mycelium Filtration Functional material Pleurotus ostreatus Water resistance

Economic overview of a two-agent process for underground coal gasification with Fischer-Tropsch- based poly-generation

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Clean Energy 2019年第1期3卷 34-46页

作者： johan F.Brand johan C.van Dyk Frans B.Waanders African Carbon Energy PO Box 450Standerton 2430South Africa Centre of Excellence in Carbon-based Fuels North-West UniversityPotchefstroom 2520South Africa African Carbon Energy PO Box 254SasolburgSouth Africa

Underground Coal Gasification(UCG)is a mining-gasification process that produces synthesis gas from in situ coal by injecting air(or oxygen and steam)and extracting the produced gas via *** resulting synthesis gas(‘syngas’)produced by UCG can be used directly as a fuel-gas or deep-cleaned to produce many other products like chemicals,liquid fuels,hydrogen and synthetic natural *** has significant environmental,safety and practical advantages over conventional coal mining and utilization,foremost being cost and emissions *** South Africa,facilities of an industrial-scale Fischer-Tropsch(FT)have been operating for decades on coal-to-liquid and gas-to-liquid ***-blown UCG produces syngas,which contains a mixture of carbon monoxide(CO)and hydrogen,and these molecules can be conditioned to serve as feed for synthetic-crude-oil(‘syncrude’)conversion technologies based on the FT *** Carbon Energy(Pty)Ltd.(Africary)completed a study integrating its UCG technology with mini gas-to-liquids *** from Africary’s Theunissen Underground Coal Gasification(TUCG)project will be used for power production and synthesis of liquid fuels in a unique poly-generation *** TUCG process will consist of two parallel gasifiers,operated on different agents,making the component parts of UCG and coal-to-(any product)(CtX)tightly linked and interdependent,but reducing both cost and ***-CtX offers a lower capital investment to conventional underground mining and surface gasification due to the removal of the surface gasifier and coal-mine *** gas clean-up systems will remove undesirable components from each gasifier and blend the cleaned syngas for H2:CO ratio control and provide implementation of carbon capture and *** study has minimized the complexity and optimized the process flow to provide own-use electricity and about 4000 barrels/day equivalent fuels at a capital cost estimate(2017)of

关键词： underground coal gasification Fischer-Tropsch coal to liquids gas to liquids CCS UCG FT LNG CtX economic study South Africa

Exhuming Asia-A thermochronological perspective： Preface

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Geoscience Frontiers 2016年第2期7卷 153-154页

作者： Stijn Glorie johan De Grave Centre for Tectonics Resources and Exploration(TRaX)Department of Earth SciencesSchool of Physical SciencesThe University of AdelaideAdelaideSA 5005Australia Department of Geology &Soil Science MINPET GroupGhent University281-S8 KrijgslaanGhent 9000Belgium

Asia is the largest continent on Earth and records a prolonged history of continental growth and tectonic reactivation during the Phanerozoic. Several tectonic forces at the continental palaeomargins induced mountain building, both at the margins themselves （e.g. the Himalayas） and into the continental interior （e.g. the Tianshan）.

关键词： Asia Exhuming Asia-A thermochronological perspective

Mapping of decentralised photovoltaic and solar thermal systems by remote sensing aerial imagery and deep machine learning for statistic generation

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Energy and AI 2023年第4期14卷 559-577页

作者： johan Lindahl Robert johansson David Lingfors Becquerel Sweden AB SE-74142 KnivstaSweden Department of Engineering Sciences Uppsala UniversitySE-75121 UppsalaSweden

As a mean to monitor the rapid expansion of the highly decentralized PV market,identifying solar energy systems in aerial imagery by deep machine learning,is a research field that is getting increasing *** general challenge in the field is to create testing data of high quality that are representative of the end-use *** this study we use the open source convolutional neural network developed within the DeepSolar project and apply it in the country of Sweden,for the purpose of generating market statistics,by scanning three complete municipalities for small decentralized photovoltaic and solar thermal *** evaluation of the performance is done against a highly accurate ground truth,which was created by cross-checking the classification results with the inventory of the local distribution system operators and the database of photovoltaic systems that have received a capital subsidy in Sweden,and combining that with physical onsite inspections.A process of generate additional training data and re-training the algorithm after each municipality scan was developed,which suc-cessively improved the accuracy,resulting in that 95%of all detectable photovoltaic,excluding building inte-grated and vertical systems,and 80%of all detectable solar thermal systems were correctly identified in the last municipality *** accurate ground truth allowed a quantification of why some systems are not *** generated dataset of solar energy systems could be connected to existing building and property inventories,which allowed creation of market segment statistics with remarkably high detail information.

关键词： Photovoltaics Solar thermal Aerial imagery Remote sensing Object recognition Convolutional neural networks

Distributed attitude synchronization using backstepping and sliding mode control

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Control Theory and Technology 2014年第1期12卷 48-55页

作者： johan THUNBERG Wenjun SONG Yiguang HONG Xiaoming HU KTH Royal Institute of Technology S-100 44 Stockholm Sweden Key Laboratory of Systems and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We consider the problem of attitude synchronization for systems of rigid body agents with directed topologies. Two different scenarios for the rotation matrices of the agents are considered. In the first scenario, the rotations are contained in a convex subset of SO（3）, which is a ball of radius less than π/2, whereas in the second scenario the agents are contained in a subset of SO（3）, which is a ball of radius less than ~. Using a control law based on backstepping and sliding mode control, we provide distributed, semi-global, torque control laws for the agents so that the rotations asymptotically synchronize. The control laws for the agents in the first scenario only depend on the relative rotations between neighboring agents, whereas the control laws in the second scenario depend on rotations defined in a global coordinate frame, lllustrative examples are provided where the synchronization is shown for both scenarios.

关键词： Attitude synchronization Distributed control Multi-agent systems

Collaboration Exercises——The Lack of Collaborative Benefits

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International Journal of Disaster Risk Science 2014年第3期5卷 192-205页

作者： johan M.Berlin Eric D.Carlstrom Department of Social and Behavioral Studies University West46186 TrollhattanSweden Sahlgrenska Academy Institute of Health and Care SciencesUniversity of Gothenburg40530 GothenburgSweden

The purpose of this article is to analyze what professional emergency personnel learn during collaboration exercises and the benefits of what they have ***(n = 19) and semistructured interviews(n = 32) were carried out in conjunction with major exercises held in Sweden(2007–2012). The results show that exercises tend to be based on their own logic, which differs from actual events. Exercise participants believe that they mainly learn single-track, parallel, and pathdependent behavior. The exercises do not facilitate the use of cross-boundary activities. This means that learning, as well as benefits from the exercises for actual events, is limited. The exercises would be more appropriate if those participating had the opportunity to identify weaknesses,try alternative ways, and engage in comprehensive organizational analyses at the conclusion of the *** on the results of the study, alternative models for collaboration exercises are suggested, with elements that would better develop collaboration and contribute to learning.

关键词： Ambulance Collaboration exercises Emergency personnel Police Rescue services Sweden