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Full scale amendment of a contaminated wood impregnation site with iron water treatment residues

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Frontiers of Environmental Science & Engineering 2016年第4期10卷 169-178页

作者： Sanne skov NIELSEN Peter KJELDSEN Rasmus JAKOBSEN Orbicon Ringstedvej 20 DK-4000 Roskilde Denmark Department of Environmental Engineering Technical University of Denmark Miljovej 113 DK-2800 Kgs. Lyngby Denmark Geological Survey of Denmark and Greenland Geological Survey of Denmark and Greenland Oster Voldgade 10 DK-1350 Copenhagen K Denmark

Iron water treatment residues （Fe-WTR） are a free by-product of the treatment of drinking water with high concentration of iron oxides and potential for arsenic sorption. This paper aims at applying Fe- WTR to a contaminated site, measuring the reduction in contaminant leaching, and discussing the design of delivery and mixing strategy for soil stabilization at field scale and present a cost-effective method of soil mixing by connnon contractor machinery. Soil contaminated by As, Cr, and Cu at an abandoned wood impregnation site was amended with 0.22% （dw） Fe-WTR. To evaluate the full scale amendment a 100 mtest site and a control site （without amendment） were monitored for 14 months. Also soil analysis of Fe to evaluate the degree of soil and Fe-WTR mixing was done. Stabilization with Fe-WTR had a significant effect on leachable contaminants, reducing pore water As by 93%, Cu by 91% and Cr by 95% in the upper samplers. Dosage and mixing of Fe-WTR in the soil proved to be difficult in the deeper part of the field, and Pire water concentrations of arsenic was generally *** water logged conditions no increase in dissolved iron or arsenic was observed in the amended soil. Our field scale amendment of contaminated soil was overall successful in decreasing leaching of As, Cr and Cu. With minor improvements in the mixing and delivery strategy, this stabilization method is suggested for use in cases, where leaching ofCu, Cr and As constitutes a risk for groundwater and freshwater.

关键词： Field experiment Iron oxide Arsenic Stabilization Wood preservation sites

Silicone rubbers for dielectric elastomers with improved dielectric and mechanical properties as a result of substituting silica with titanium dioxide

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International Journal of Smart and Nano Materials 2015年第4期6卷 268-289页

作者： Liyun Yu Anne Ladegaard skov The Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of Denmark2800 Kgs.LyngbyDenmark

One prominent method of modifying the properties of dielectric elastomers(DEs)is by adding suitable metal oxide ***,almost all commercially available sili-cone elastomers are already heavily filled with silica to reinforce the otherwise rather weak silicone network and the resulting metal oxide filled elastomer may contain too much *** therefore explore the replacement of silica with titanium dioxide to ensure a relatively low concentration of *** silicone rubber(LSR)has relatively low viscosity,which is favorable for loading inorganic *** the present study,four commercial LSRs with varying loadings of silica and one benchmark room-temperature vulcanizable rubber(RTV)were *** resulting elastomers were evaluated with respect to their dielectric permittivity,tear and tensile strengths,electrical breakdown,thermal stability and dynamic *** silicone elasto-mers with high loadings of nano-sized titanium dioxide(TiO_(2))particles were also *** best overall performing formulation had 35 wt.%TiO_(2) nanoparticles in the POWERSIL®XLR LSR,where the excellent ensemble of relative dielectric permittivity of 4.9 at 0.1 Hz,breakdown strength of 160 V µm^(−1),tear strength of 5.3 MPa,elongation at break of 190%,a Young’s modulus of 0.85 MPa and a 10% strain response(simple tension)in a 50 Vμm^(−1) electric field was obtained.

关键词： silicone rubber titanium dioxide dielectric permittivity mechanical properties electrical breakdown

Incorporation of liquid fillers into silicone foams to enhance the electro-mechanical properties

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International Journal of Smart and Nano Materials 2020年第1期11卷 11-23页

作者： Min Liu Liyun Yu Sindhu Vudayagiri Anne Ladegaard skov School of Materials Science and Engineering East China University of Science and TechnologyShanghaiChina Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkKongens LyngbyDenmark

Silicone foams with and without liquid fillers(silicone oils of various types and glycerol,respectively)are synthesized and analyzed to be used as dielectric layers in capacitive sensors.A simple fabrication technique involving only four components *** 184,glycerol,sodium hydroxide and ethanol is used to make these silicone foams after which they are filled with silicone oil or glycerol by soaking the foam in respective *** and dielectric properties of the foams are *** oil reinforces the foam’s dielectric properties,softens the foam and improves its capacitive response,making it a very good dielectric material for fabricating capacitive pressure *** to dry silicone foams,foams filled with-and swollen by-chloropropyl-functional silicone oil,show a low Young’smodulus(31 kPa),a high and stable relative dielectric permittivity of around 5,and a high capacitive response of 132%for an appliedpressureof 12 *** of oil stabilizes the soft foam and ensures that it does not buckle under high pressure.

关键词： Silicone foams electro-mechanical capacitive pressure sensors glycerol silicone oil chloropropyl-functional silicone oil

A methodological framework for analyzing PPGIS data collected in 3D

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International Journal of Digital Earth 2023年第1期16卷 3435-3455页

作者： Kamyar Hasanzadeh Nora Fagerholm Hans skov-Petersen Anton Stahl Olafsson Department of Geography and Geology University of TurkuTurkuFinland Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark

Public participation geographic information system(PPGIS)is a facilitated Volunteered Geographic Information approach and data collection method that aims to capture the spatial experiences of *** we experience the space around us three-dimensionally,altitude,as the third dimension,has been often absent from PPGis research and *** is largely because of the complexity of implementing surveys in 3D but can also be attributed to a lack of analytical preparedness for using such *** study complements 3D PPGIS data collected from a pilot study of the Aninkainen block in Turku,Finland with synthetic,*** manufactured,data to propose an analytical framework for the study of 3D PPGIS *** analytical framework divides methods based on the geographical scale into two groups:micro-and macro-scale *** this framework,we propose the use of geospatial metrics to analyze 3D PPGIS *** argue that while this multidisciplinary area of research is in its infancy,use of intuitive 3D adapted geometric and landscape metrics can help overcome some of complexities associated with use of this emerging participatory *** conclude by outlining the limitations and envisioning areas for future research.

关键词： 3D GIS landscape metrics PPGIS

Degradation patterns of silicone-based dielectric elastomers in electrical fields

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International Journal of Smart and Nano Materials 2018年第4期9卷 217-232,I0001页

作者： Liyun Yu Frederikke B.Madsen Anne L.skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

Silicone elastomers have been heavily investigated as candidates for the flexible insulator material in dielectric elastomer transducers and are as such almost ideal candidates because of their inherent softness and ***,silicone elastomers suffer from low dielectric *** shortcoming has been attempted optimized through different approaches during recent *** optimization with the sole purpose of increasing the dielectric permittivity may lead to the introduction of problematic phenomena such as premature electrical breakdown due to high leakage currents of the thin elastomer *** this work,electrical breakdown phenomena of various types of permittivity-enhanced silicone elastomers are *** showed that different types of polymer backbone chemistries lead to differences in electrical breakdown patterns,which were revealed through SEM *** may pave the way towards a better understanding of electrical breakdown mechanisms of dielectric elastomers and potentially lead to materials with increased electrical breakdown strengths.

关键词： Silicone elastomers dielectric electrical breakdown voltage stabilization characterization

Temperature dependence of dielectric breakdown of silicone-based dielectric elastomers

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International Journal of Smart and Nano Materials 2020年第2期11卷 129-146页

作者： Liyun Yu Sindhu Vudayagiri Lucy Ajakaiye Jensen Anne Ladegaard skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkLyngbyDenmark

A large number of insulation/dielectric failures in power systems are related to thermally-induced dielectrical breakdown,also known as‘thermal breakdown’,at higher operating *** this work,the thermal breakdown behavior of typical silicone formulations,used as dielectrics in stretchable electronic devices,is analyzed at practically relevant operating temperatures ranging from 20℃ to 80℃.An effective way of delaying the thermal breakdown of insulating materials is to blend micro-or nano-sized inorganic particles with high thermal conductivity,to dissipate better any losses generated during energy ***,two types of commercial silicone formulations,blended with two types of rutile hydrophobic,high-dielectric TiO_(2) fillers,are investigated in relation to their dielectric properties,namely,relative permittivity,the dissipation factor,and electrical breakdown *** breakdown strengths of these silicone composites are subsequently evaluated using Weibull analysis,which indicates a negative correlation between temperature and shape parameter for all compositions,thus illustrating that the homogeneity of the samples decreases in line with temperature,but the breakdown strengths nevertheless increase initially due to the trapping effect from the high-permittivity fillers.

关键词： Silicone elastomers titanium dioxide fillers dielectric breakdown strength Weibull temperature

Reduced energy consumption by using streamlined gating systems

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China Foundry 2008年第4期5卷 272-279页

作者： Sфren skov-Hansen Niels Skat Tiedje DISA Industries A/S Technical University of Denmark

In foundries a lot of effort is done to minimize energy consumption in the production to reduce costs and hence increase the competitiveness. At the same time the foundries must live up to the increased demands for high quality castings. Traditional gating systems are known for a straight tapered down runner, a well base and 90° bends in the runner system. Previous work has shown that the traditional way of designing gating systems creates high inconsistency in flow patterns during filling. In the streamlined gating systems there are no sharp changes in direction and a large effort is done to confine and control the flow of the molten metal during mould filling. The main objective in the work presented here is to use the principles of the streamlined gating systems to reduce the weight of the gating system relative to the traditional layouts. By reducing the weight of gating system and thereby improving yield, the amount of molten iron needed is also reduced, hence reducing the energy consumption for melting. Experiments in real production lines have proven that it is possible to achieve a reduction in the poured weight by using the streamlined gating systems. In a layout for casting of three valve housings in a vertically parted mould the weight of the gating system was reduced by 1.1 kg changing from the traditional layouts to the streamlined gating systems. This weight reduction corresponds in this case to a 20% weight reduction for the gating system. Using streamlined gating systems with fan gates to give a beneficial heat distribution in the castings may be an efficient tool to eliminate the need for heat treatment. In the experiments the change in gating system from the traditional layout to the streamlined layout removed the need for heat treatment. This obviously means a huge energy saving in the foundry. The energy consumption for heat treatment of iron has been found to be 0.489 kWh/ kg. The valve housing in the experiments weighs 3 kg so when the need

关键词： streamlined gating systems energy consumption mould filling weight layout

Potential Significance of the EU Water Framework Directive to China

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人民长江 2009年第8期40卷 54-62页

作者： Lars skov Andersen Martin Griffiths EU China River Basin Management Advisory Team

The European Union Water Framework Directive (EU WFD) is a unique piece of legislation, which may be of great significance to on-going reforms of the water sector in China. First and foremost it unites 27 European member states behind a common goal, which is "to achieve good chemical and ecological status" of all water bodies across the EU. Other significant characteristics of the EU WFD are that (1) it sets a clear timeframe with a number of time-bound actions for member states to achieve the goal, but leaves it to member states to achieve this goal in a decentralised process, which makes allowance for the different socio-economic conditions, (2) it defines the river basin as the management unit for water thus departing with the traditional fragmented management by administrative units and it appoints a single competent authority for water management within each river basin, thus facilitating resolution of sector conflicts, (3) it requires a financial and economic analysis of the costs of implementing the EU WFD to enable decision makers to assess whether the required improvements are affordable to government and to the population within the river basin, and (4) it requires a structured process for information and consultation with stakeholders and the public throughout the planning and implementation process.

关键词： Potential Significance of the EU Water Framework Directive to China EU

Electron transfer in phosphorylated peptide--Study of laser photolysis on N-dipp-TrpH-TyrOH peptide

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Chinese Journal of Chemistry 1995年第4期13卷 324-333页

作者： WANG, ZY ZHANG, ZC ZHANG, mw UNIV SCI & TECHNOL CHINA DEPT CHEM PHYSHEFEI 230026PEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST NUCL RESRADIAT CHEM LABSHANGHAI 201800PEOPLES R CHINA

The Laser photolysis of N-diisopropyl phosphoryl tryptophyl. tyrosine dipeptide methyl ester (N-DiPP-TrpH-TyrOH) has been carried out utilizing a KrF(248 nm) laser. The direct intramolecular ET between TrpH(+) residue and TyrOH residue was detected first and the ET between Trp. and TyrOH became dow. It was suggested that phosphoryl group stabilize neighbour radical of aromatic ring by hyperconjugation. In combination with computer modeling we obtained the kinetic parameters of the ET and proved that phosphoryl groups took part in the process of ET. The results should be significant for biological system since every biological process involves the phosphorylations or nonphosphorylation.

关键词： ELECTRON TRANSFER PHOSPHORYLATED PEPTIDE PHOTOLYSIS