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DEPOSITION OF TiBN HARD FILMS ON HOT-WORKING-STEEL DIES FOR ALUMINIUM EXTRUSION VIA A DUPLEX PROCESS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 408-414页

作者： K. Muller (Forschungszentrum Stranpressen, TU berlin, 13355 berlin, Germany) Forschungszentrum Stranpressen TU Berlin 13355 Berlin Germany

Hot working steels have been used as die materials for hot extrusion of aluminium. Due to tribological interaction at elevated temperature between the die bearing and the surface of extruded aluminium profiles, not only the surface quality of the extruded product, but also the lifetime of the dies decreases. Deposition of TiBN hard films on the die bearing could improve the die performance. Treatment should be done in a duplex process process combining a plasma nitriding pretreatment (PN) and a plasma assisted chemical vapour deposition (PACVD) of TiBN. In this study the influence of the process conditions on the properties of the duplex coatings was investigated. The relationship between structure and mechanical property was researched. For testing these TIBN hard films under elevated temperature conditions and for comparison with other possible coatings special extrusion dies with different coated bearings were used. The extrusion trials were performed on the 8MN-extrusion press at the research a nd development center for extrusion, Technical University of berlin.

关键词： hard film plasma nitriding duplex process PN PA CVD and extrusion

Skeletal faunas from the Qiongzhusian of southern Shaanxi: biodiversity and lithofacies-biofacies links in the Lower Cambrian carbonate settings

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Progress in Natural Science:Materials International 2004年第1期14卷 92-97页

作者： Michael STEINER 13355 berlin Ackerstrasse 71～76 Germany Technische Universitt berlin Sekr.ACK 14

The Xiaoyang section, located in Zhenba County of Shaanxi Province, is important both for documenting the biodiversity of the Qiongzhusian Stage (Lower Cambrian) and for analyzing lithofacies biofacies links in carbonate depositing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, including linguloid valves, cambroclavid and chancelloriid sclerites, genal and occipital spines of polymerid trilobites, and tubular fossils, are described here as the Eoobolus Cambroclavus fauna, which mainly occurred in peritidal environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopods, eodiscoid trilobites, bivalved arthropods, microdictyoniid sclerites and siliceous sponge spicules, are regarded as the Palaeobolus Hupeidiscus Kunmingella fauna, which presumably lived in subtidal or deeper water environments. The faunal diversity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern Shaanxi will significantly contribute to a detailed documentation of the biodiversity during the Qiongzhusian interval on the Yangtze Platform and add new knowledge on the Cambrian bioradiation.

关键词： skeletal fauna Xihaoping Member Shuijingtuo Formation Lower Cambrian Shaanxi

Assessment of toxicity potential of metallic elements in discarded electronics:A case study of mobile phones in China

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Journal of Environmental Sciences 2008年第11期20卷 1403-1408页

作者： A.Middendorf Department of Environmental Engineering Fraunhofer IZMGustav-Meyer-Allee 2513355 BerlinGermany

The electronic waste (e-waste) is increasingly flooding Asia,especially China.E-waste could precipitate a growing volume of toxic input to the local environment if it was not handed *** makes the evaluation of environmental impact from electronics an essentially important task for the life cycle assessment (LCA) and the end-of-life management of electronic *** study presented a quantitative investigation on the environmental performance of typical *** types of disposed mobile...

关键词： e-waste enviromental impact toxicity potential indicator (TPI) mobile phones (MPs)

Phosphorus recovery from municipal and fertilizer wastewater:China's potential and perspective

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Journal of Environmental Sciences 2017年第2期29卷 151-159页

作者： Kuangxin Zhou Matthias Barjenbruch Christian Kabbe Goulven Inial Christian Remy berlin Centre of Competence for Water Berlin 10709Germany Department of Urban Water Management Technical University of BerlinBerlin 13355Germany Research&Innovation Asia Veolia EnvironmentBeijing 10004China

Phosphorus（P） is a limited resource, which can neither be synthesized nor substituted in its essential functions as nutrient. Currently explored and economically feasible global reserves may be depleted within generations. China is the largest phosphate fertilizer producing and consuming country in the world. China’s municipal wastewater contains up to 293,163 Mg year of phosphorus, which equals approximately 5.5% of the chemical fertilizer phosphorus consumed in China. Phosphorus in wastewater can be seen not only as a source of pollution to be reduced, but also as a limited resource to be recovered. Based upon existing phosphorus-recovery technologies and the current wastewater infrastructure in China, three options for phosphorus recovery from sewage sludge, sludge ash and the fertilizer industry were analyzed according to the specific conditions in China.

关键词： Phosphorus recovery Municipal Wastewater Fertilizer Industry Sewage sludge China

Closed-loop hydrometallurgical treatment of end-of-life lithium ion batteries: Towards zero-waste process and metal recycling in advanced batteries

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Journal of Energy Chemistry 2019年第8期28卷 220-227,I0008页

作者： Thomas Abo Atia Giuseppe Elia Robert Hahn Pietro Altimari Francesca Pagnanelli Department of Chemistry Sapienza University of RomeRome 00185 Italy Waste Recycling Technologies Flemish Institute for Technological ResearchMol 2400 Belgium Technische Universitat berlin Research Center of Microperipheric TechnologiesBerlin D-13355 Germany Fraunhofer-Institut für Zuverlassigkeit und Mikrointegration Berlin D-13355 Germany

This work presents an enhanced hydrometallurgical process for recycling lithium ion batteries. First, endof-life batteries were processed in a physical pre-treatment plant to obtain a representative electrode material. The resulting leachate was purified forth by iron-precipitation, liquid–liquid extractions, and an innovative Li–Na separation, in order to obtain valuable products. These products include high-grade graphite, cobalt oxide(Co3O4, purity 83%), cobalt oxalate(CoC2O4, purity 96%), nickel oxide(Ni O, purity89%), and lithium carbonate(Li2CO3, purity 99.8%). The recovery rate was quantitative for graphite, between 80% and 85% for cobalt depending on the nature of the recovery method, 90% for nickel, and 72%for lithium. Secondary streams were also valorized to obtain sodium sulfate(Na2SO4, purity 96%), and MnCoFe2O4 magnetic nano-sorbents according to the zero-waste concept. In order to close the loop, recycled Co3O4 and NiO were used as conversion-type anode materials for advanced lithium ion batteries showing promising performances.

关键词： LIB recycling Graphite Cobalt Nickel Lithium Advanced LIB

Wave propagation speeds and source term influences in single and integral porosity shallow water equations

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Water Science and Engineering 2017年第4期10卷 275-286页

作者： Ilhan Ozgen Jia-heng Zhao Dong-fang Liang Reinhard Hinkelmann Department of Civil Engineering Technische Universitat BerlinBerlin 13355Germany Department of Engineering University of CambridgeCambridge CB2 1PZUK

In urban flood modeling,so-called porosity shallow water equations(PSWEs),which conceptually account for unresolved structures, e.g.,buildings, are a promising approach to addressing high CPU times associated with state-of-the-art explicit numerical methods. The PSWE can be formulated with a single porosity term, referred to as the single porosity shallow water model(SP model), which accounts for both the reduced storage in the cell and the reduced conveyance, or with two porosity terms: one accounting for the reduced storage in the cell and another accounting for the reduced conveyance. The latter form is referred to as an integral or anisotropic porosity shallow water model(AP model). The aim of this study was to analyze the differences in wave propagation speeds of the SP model and the AP model and the implications of numerical model results. First, augmented Roe-type solutions were used to assess the influence of the source terms appearing in both models. It is shown that different source terms have different influences on the stability of the models. Second, four computational test cases were presented and the numerical models were compared. It is observed in the eigenvalue-based analysis as well as in the computational test cases that the models converge if the conveyance porosity in the AP model is close to the storage porosity. If the porosity values differ significantly, the AP model yields different wave propagation speeds and numerical fluxes from those of the BP model. In this study, the ratio between the conveyance and storage porosities was determined to be the most significant parameter.

关键词： Porosity Macroscopic modeling of urban flooding Wave propagation speed Godunov flux Single porosity shallow water model Anisotropic porosity

Comparison of depth-averaged concentration and bed load flux sediment transport models of dam-break flow

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Water Science and Engineering 2017年第4期10卷 287-294页

作者： Jia-heng Zhao Ilhan Ozgen Dong-fang Liang Reinhard Hinkelmann Department of Civil Engineering Technische Universitat BerlinBerlin 13355Germany Department of Engineering University of CambridgeCambridge CB2 1PZUK

This paper presents numerical simulations of dam-break flow over a movable bed. Two different mathematical models were compared: a fully coupled formulation of shallow water equations with erosion and deposition terms(a depth-averaged concentration flux model), and shallow water equations with a fully coupled Exner equation(a bed load flux model). Both models were discretized using the cell-centered finite volume method, and a second-order Godunov-type scheme was used to solve the equations. The numerical flux was calculated using a Harten, Lax, and van Leer approximate Riemann solver with the contact wave restored(HLLC). A novel slope source term treatment that considers the density change was introduced to the depth-averaged concentration flux model to obtain higher-order accuracy. A source term that accounts for the sediment flux was added to the bed load flux model to reflect the influence of sediment movement on the momentum of the water. In a onedimensional test case, a sensitivity study on different model parameters was carried out. For the depth-averaged concentration flux model,Manning's coefficient and sediment porosity values showed an almost linear relationship with the bottom change, and for the bed load flux model, the sediment porosity was identified as the most sensitive parameter. The capabilities and limitations of both model concepts are demonstrated in a benchmark experimental test case dealing with dam-break flow over variable bed topography.

关键词： Shallow water Sediment transport Bed load flux model Depth-averaged concentration flux model Dam break

Eocrinoid echinoderms from the Lower Cambrian Guanshan Fauna in Wuding,Yunnan,China

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Chinese Science Bulletin 2007年第5期52卷 717-719页

作者： HU ShiXue LUO HuiLin HOU ShuGuang Bernd-Dietrich ERDTMANN Yunnan Institute of Geological Sciences Kunming 650011 China Technische Universitat Bedin D-13355 Berlin Germany

This is a brief report of a new occurrence of eocrinoids from the Early Cambrian Wulongqing Formation in Yunnan, China. The eocrinoids from the Guanshan fauna are among the earliest known eocrinoids. Different from many other Early and Middle Cambrian eocrinoids, the Guanshan eocrinoids are char-acterized by the absence of sutural pores and epispires, the long and spiral brachioles, the extremely long stalk, and the ratio of the length of the stalk versus that of the calyx. The discovery of the eocri-noids from the Guanshan fauna not only provides new information to the investigation of the early evolution of this animal group, but also shed new light on the occurrence and migration of early eocrinoids.

关键词：棘皮类动物下寒武统关山动物群化石云南武定

The NMR core analyzing tomograph:a multi-functional tool for non-destructive testing of building materials

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Magnetic Resonance Letters 2023年第3期3卷 207-219,I0003页

作者： Sabine Kruschwitz Sarah Munsch Melissa Telong Wolfram Schmidt Thilo Bintz Matthias Fladt Ludwig Stelzner Bundesanstalt für Materialforschung und-prüfung Unter den Eichen 87Berlin12205Germany Technische Universitat berlin Gustav-Meyer-Allee 25Berlin13355Germany

NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the *** on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore *** it enables the determination of moisture transport properties and the(re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and ***,as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale(<10 mL)*** paper describes the capabilities of an NMR tomograph,which has been specifically optimized for the investigation of larger,heterogeneous building material samples(diameters of up to 72 mm,length of up to 700 mm)with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times(50-80 ms).

关键词： Natural stone Concrete Sensitivity Moisture transport Cement hydration Supplementary cementitious materials Frost and salt attack Fire spalling