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Ultrasound enhanced friction stir welding of aluminum and steel： Process and properties of EN AW 6061/DC04-Joints

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Journal of Materials Science & Technology 2018年第1期34卷 163-172页

作者： Marco Thoma Guntram Wagner Benjamin Straβ bernd Wolter Sigrid Benferc Wolfram Furbeth Chair of Composites and Material Compounds Chemnitz University of Technology Chemnitz 09125 Germany Fraunhofer Institute for Nondestructive Testing IZFP Saarbrucken 66123 Germany DECHEMA-Forschungsinstitut Frankfurt am Main 60486 Germany

In this work, the joining of aluminum to steel was conducted by ultrasound enhanced friction stir weld- ing （USE-FSW）. The power ultrasound was introduced into one of the metal sheets by an ultrasonic roll seam module synchronously to the FSW-process. The effect of the ultrasound on the resulting welds, their microstructure and their corrosion properties was investigated by light and scanning electron microscopy and corrosion investigations. The USE-FSW-joints showed less and smaller steel particles in the nugget zone as well as a thinner continuous intermetallic phase of FeAl3 at the interface. The nondestructive testing method of computed laminography proved the observations made by optic microscopy due to non-porous joints for both techniques. Corrosion investigations showed only low corrosion current densities and no enhanced galvanic corrosion for the EN AW-6061/DC04-hybrid joints in sodium chloride solution.

关键词： Friction stir welding Ultrasound enhancement Dissimilar joints Corrosion

Antioxidant,nutritional and anti-nutritional composition of Garcinia kola and Chrysophyllum albidum from rainforest ecosystem of Ondo State,Nigeria

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Journal of Forestry Research 2015年第2期26卷 417-424页

作者： Jonathan C.Onyekwelu Olufunmilayo Oyewale bernd Stimm Reinhard Mosandl Department of Forestry and Wood Technology Federal University of Technology Institute of Silviculture Technische Universit?t Muenchen

Tropical forests contain many tree species that have supplied edible fruits for *** fruits have contributed to human diets due to their richness in nutrients,vitamins,minerals,antioxidants and their low antinutrients *** investigated the antioxidant,nutritional and anti-nutritional composition of Garcinia kola and Chrysophyllum albidum fruit *** nutritional,anti-nutritional and antioxidant compositions differed depending on the fruit *** of fruit part,moisture content was high（72–93 %）.While the edible part（fruit pulp） of *** proved a better source of protein（4）,fibre（17 %） and fat（2 %）,the seed kernel was a better source of ash（2 %） and carbohydrate（15 %）.Carbohydrate（22 %）,protein（2 %）,fat（1 %） and fibre（3 %） were higher in *** seed kernel（edible part） than in the pulp and ***-nutrient content in *** and *** fruits was low,indicating that their consumption would not pose nutritional or health *** antioxidant compositions（especially phenolic content（10–21 mg g-1） and DPPH（1,1-diphenyl–2 picrylhydrazyl）（26–55 %）） of *** fruit pulp and *** seed kernel were high,implying that they could be good sources of natural antioxidants and could be used as supplements in food manufacturing.

关键词： Forest food trees Livelihood Antioxidant Nutritional supplement Tropical forests Garcinia kola Chrysophyllum albidum Nigeria

Sustainable waste management for zero waste cities in China:potential,challenges and opportunities

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Clean Energy 2020年第3期4卷 169-201页

作者： Roh Pin Lee bernd Meyer Qiuliang Huang Raoul Voss Institute for Energy Process Engineering and Chemical Engineering TU Bergakademie FreibergGermany Fraunhofer IMWS Branch Lab‘Circular Carbon Technologies’ FreibergGermany Institute of Coal Chemistry Chinese Academy of SciencesTaiyuanChina

Waste is a valuable secondary carbon *** the linear economy,it is predominantly landfilled or *** disposal routes not only lead to diverse climate,environmental and societal problems;they also represent a loss of carbon *** a circular carbon economy,waste is used as a secondary carbon feedstock to replace fossil resources for *** contributes to environmental protection and resource *** furthermore increases a nation’s independence from imported fossil energy *** is at the start of its transition from a linear to circular carbon *** can thus draw on waste management experiences of other economies and assess the opportunities for transference to support its development of‘zero waste cities’.This paper has three main *** is an assessment of drivers for China’s zero waste cities initiative and the approaches that have been implemented to combat its growing waste *** is a sharing of Germany’s experience-a forerunner in the implementation of the waste hierarchy(reduce-reuse-recycle-recover-landfill)with extensive experience in circular carbon technologies-in sustainable waste *** is an identification of transference opportunities for China’s zero waste *** transference opportunities identified range from measures to promote waste prevention,waste separation and waste reduction,generating additional value via mechanical recycling,implementing chemical recycling as a recycling option before energy recovery to extending energy recovery opportunities.

关键词： circular carbon economy waste-to-energy zero waste cities sustainable waste management recycling

A new model describing Forbush Decreases at Mars: combining the heliospheric modulation and the atmospheric influence

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Earth and Planetary Physics 2020年第1期4卷 62-72页

作者： Jingnan Guo Robert FWimmer-Schweingruber Mateja Dumbović bernd Heber YuMing Wang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Institute of Experimental and Applied Physics Christian-Albrechts-UniversityKielDE 24118Germany Hvar Observatory Faculty of GeodesyUniversity of ZagrebCroatia

Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction regions (SIRs/CIRs). Forbush decreases have been studied extensively using neutron monitors at Earth;recently, for the first time, they have been measured on the surface of another planet, Mars, by the Radiation Assessment Detector (RAD) on board the Mars Science Laboratory’s (MSL) rover Curiosity. The modulation of GCR particles by heliospheric transients in space is energy-dependent;afterwards, these particles interact with the Martian atmosphere, the interaction process depending on particle type and energy. In order to use ground-measured Forbush decreases to study the space weather environment near Mars, it is important to understand and quantify the energy-dependent modulation of the GCR particles by not only the pass-by heliospheric disturbances but also by the Martian atmosphere. Accordingly, this study presents a model that quantifies both at the Martian surface and in the interplanetary space near Mars the amplitudes of Forbush decreases at Mars during the pass-by of an ICME/SIR by combining the heliospheric modulation of GCRs with the atmospheric modification of such modulated GCR spectra. The modeled results are in good agreement with measurements of Forbush decreases caused by ICMEs/SIRs based on data collected by MSL on the surface of Mars and by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft in orbit. Our model and these findings support the validity of both the Forbush decrease description and Martian atmospheric transport models.

关键词： ICME and Forbush decreases space weather at Mars Mars:atmosphere GCR radiation

Comparison of three different CFD methods for dense fluidized beds and validation by a cold flow experiment

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Particuology 2016年第6期14卷 34-47页

作者： Alexander Stroh Falah Alobaid Max Thomas Hasenzahl] Jochen Hilz Jochen Strohle bernd Epple Technische Universitdt Darmstadt Institute for Energy Systems and Technology Otto-Berndt-Straβe 2 64287 Darmstadt Germany

This work focuses on a comparison between three different numerical CFD methods, namely Euler-Euler, Euler-Lagrange-stochastic, and Euler-Lagrange-deterministic, to treat a dense spouted bed, A simple cold flow experiment was used to investigate the hydrodynamics of a gas-solid flow in a three dimensional lab-scale spouted bed, In this context, two different air mass flow rates, 0,005 and 0.006 kg/s, were applied during fluidization. The experimental bed behaviour was recorded with a high-speed camera to validate the numerical predictions in terms of bubble size, bed expansion rate, and particle velocities at different reactor heights. The numerical setup was kept similar between all three modelling approaches, At both gas mass flow rates all three approaches are able to capture the overall bed expansion. However, at higher gas mass flow rates, discrepancies between experiment and simulation increase for the Euler-Euler and Euler-Lagrange-stochastic models. The Euler-Lagrange deterministic model most accurately predicts the flow pattern at both mass flow rates. The main reasons for discrepancies between simulation and experiment result from modelling of the collision and friction forces.

关键词： Computational fluid dynamics Euler-Lagrange-deterministic collisionmodel Euler-EulerMP-PIC approach Experimental validation

Gut microbiota,fatty liver disease,and hepatocellular carcinoma

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Liver Research 2018年第1期2卷 43-51页

作者： Huikuan Chu Brandon Williams bernd Schnabl Division of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Medicine University of California San DiegoLa JollaCAUSA Department of Medicine VA San Diego Healthcare SystemSan DiegoCAUSA

Intestinal bacteria contribute to the pathogenesis of non-alcoholic fatty liver disease(NAFLD).Recently developed microbial profiling techniques are beginning to shed light on the nature of the changes in the gut microbiota that accompany NAFLD and non-alcoholic steatohepatitis(NASH).In this review,we summarize the role of gut microbiota in the development of NAFLD,NASH,and hepatocellular carcinoma(HCC).We highlight the mechanisms by which gut microbiota contribute to NAFLD/NASH,including through alterations in gut epithelial permeability,choline metabolism,endogenous alcohol production,release of inflammatory cytokines,regulation of hepatic Toll-like receptor(TLR),and bile acid *** addition,we analyze possible mechanisms for enhanced hepatic carcinogenesis,including alterations in bile acid metabolism,release of inflammatory cytokines,and expression of ***,we describe therapeutic approaches for NAFLD/NASH and preventive strategies for HCC involving modulation of the intestinal microbiota or affected host *** recent studies have provided useful information,large-scale prospective studies are required to better characterize the intestinal microbiota and metabolome,in order to demonstrate a causative role for changes in the gut microbiota in the etiology of NAFLD/NASH,to identify new therapeutic strategies for NAFLD/NASH,and to develop more effective methods of preventing HCC.

关键词： Gut microbiota Intestinal microbiome Metabolome Metagenome Fatty liver disease Non-alcoholic fatty liver disease(NAFLD) Non-alcoholic steatohepatitis(NASH)Hepatocellular carcinoma(HCC)

Salt lakes in China:Challenges for reconstructing ecological and climate variations

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 199-200页

作者： bernd WüNNEMANN School of Geographic and Oceanographic Sciences Nanjing University Institute of Geographical Science Freie Universitt Berlin

1 Introduction Studies on lakes have become an important concern for many scientists since it is well known that lakes can monitor detailed information about ecological,hydrological and sedimentary cycles which can be

关键词： Lake basin Lake catchment sediment variability tectonics climate change Tibetan Plateau China.

Greenhouse gas emission and its potential mitigation process from the waste sector in a large-scale exhibition

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Journal of Environmental Sciences 2015年第5期27卷 44-50页

作者： Ziyang Lou bernd Bilitewski Nanwen Zhu Xiaoli Chai Bing Li Youcai Zhao Peter Otieno School of Environmental Science and Engineering Shanghai Jiaotong University Institute for Waste Management and Contaminated Sites Treatment TU Dresden Faculty of Forestry Geo and Hydro SciencesPratzschwitzer Str.1501796 Pirna Germany State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Institute of Ecological Chemistry Helmholtz Zentrum Müenchen German National Research Centre for Environmental HealthIngolst?dter Landstrasse 1D-85764 Neuherberg Germany Maseno University Department of Chemistry

As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission（GHG）, and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment（LCA）. Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO2-equivalent（CO2-eq.）, 4.43 kg SO2-eq., 4.88 kg NO-3-eq., and 3509 m3 water per ton tourist waste were found to be released in terms of global warming（GW）, acidification（AC）,nutrient enrichment（NE） and spoiled groundwater resources（SGWR）, respectively. The total GHG emission was around 3499 ton CO2-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO2-eq.,and CH4, CO and other hydrocarbons（HC） were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton *** could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.

关键词： GHG emission Mitigation process Waste sector Expo 2010 Shanghai Life cycle assessment

Influence of Taxation on Supply and Demand in Tomorrow's Crowd Energy Paradigm

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Journal of Electronic Science and Technology 2015年第3期13卷 237-245页

作者： James Craven Evgenia Derevyanko Mario Gstrein bernd Teufel the International Institute of Management in Technology University of Fribourg

The emergence of the energy self-sufficient home presents a new role for government taxation. Policymakers now face the challenge of reflecting this technological change in their decision-making and must assume a greater level of engagement. This paper proposes a number of original fiscal concepts for policymakers to implement in the support of micro-grid development. These are designed to optimise a sustainable transition away from the centralised energy system whilst creating shared value among stakeholders throughout the value chain. Concepts are based on residential micro-grid schemata in Switzerland and are applicable in other countries.

关键词： Carbon tax crowd energy energy harvesting energy storage government micro-grids photovoltaic systems power generation economics