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Sorption and phase distribution of ethanol and butanol blended gasoline vapours in the vadose zone after release

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Journal of Environmental Sciences 2014年第3期26卷 608-616页

作者： Ejikeme Ugwoha John M. andresen Chemical and Environmental Engineering University of Nottingham School of Engineering and Physical Sciences Heriot-Watt University

The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOM） and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient （Kd） of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane （MCP） and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for MCP and 49% for benzene, The retardation factor （R） of E20 gasoline compounds decreased by 53% for pentane, 53% for MCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for MCP and 38% for benzene. For all SOM and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline 〉 B20 〉 E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination,

关键词： butanol-blended gasoline ethanol-blended gasoline phase distribution soil organic matter soil water content sorption vadose zone

Secondary seed dispersal by dung beetles in an Amazonian forest fragment of Colombia:influence of dung type and edge effect

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Integrative Zoology 2011年第4期6卷 399-408页

作者： Carolina SANTOS-HEREDIA Ellen andresen Pablo STEVENSON Department of Biological Sciences University of the AndesBogotaColombia Center for Ecosystem Research at the National Autonomous University of Mexico MoreliaMexico

Seeds of many plant species are secondarily dispersed by dung beetles,but the outcome of this interaction is highly *** is known about how certain anthropogenic disturbances affect this plant-animal *** aims of this study were to assess the effect of dung type on secondary dispersal by dung beetles in a forest fragment,and to determine whether this interaction is affected by edge *** pitfall traps,we captured dung beetles attracted to dung of 2 frugivorous mammals:woolly monkeys and howler *** found differences between both dung beetle assemblages,but these differences were not consistent in *** seeds surrounded by both dung types,we carried out a field experiment using seeds of 2 plant *** found that the probability of secondary dispersal by dung beetles was higher for seeds placed in woolly monkey ***,we carried out a field experiment using plastic beads as seed mimics to assess edge *** found that secondary seed dispersal by dung beetles was negatively affected by *** disruption of plant-animal interactions along anthropogenic forest edges could have long-term negative effects on forest dynamics by affecting processes of regeneration.

关键词： fragmentation plant-animal interaction Scarabaeidae seed fate

Oscillating Casimir force between two slabs in a Fermi sea

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Chinese Physics B 2012年第1期21卷 110-114页

作者： Chen Li-Wei Su Guo-zhen Chen Jin-can andresen Bjarne Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen UniversityXiamen 361005China Niels Bohr Institute University of CopenhagenUniversitetsparken 5DK-2100 Copenhagen∅Denmark

The Casimir effect for two parallel slabs immersed in an ideal Fermi sea is investigated at both zero and nonzero temperatures. It is found that the Casimir effect in a Fermi gas is distinctly different from that in an electromagnetic field or a massive Bose gas. In contrast to the familiar result that the Casimir force decreases monotonically with the increase of the separation L between two slabs in an electromagnetic field and a massive Bose gas, the Casimir force in a Fermi gas oscillates as a function of L. The Casimir force can be either attractive or repulsive, depending sensitively on the magnitude of L. In addition, it is found that the amplitude of the Casimir force in a Fermi gas decreases with the increase of the temperature, which also is contrary to the case in a Bose gas, since the bosonic Casimir force increases linearly with the increase of the temperature in the region T 〈 Tc, where Tc is the critical temperature of the Bose Einstein condensation.

关键词： Casimir effect Fermi gas parallel slab oscillation

Biologically Inspired Girder Structure for the Synchrotron Radiation Facility PETRA IV

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Journal of Bionic Engineering 2023年第5期20卷 1996-2017页

作者： Simone andresen Norbert Meyners Daniel Thoden Markus Körfer Christian Hamm Bionic Lightweight Design&Functional Morphology Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research(AWI)Am Handelshafen 1227570BremerhavenGermany Deutsches Elektronen-Synchrotron(DESY) Notkestraße 8522607HamburgGermany

Lightweight structures are widely used across different industry ***,they get easily excited by external influences,such as *** high vibration amplitudes can be avoided by shifting the structural eigenfrequencies,which can be achieved adapting the structural design considering optimisation procedures and structures primarily inspired by *** procedures has been applied to the development process of a girder structure installed in a synchrotron radiation facility to support heavy magnets and other *** objective was to design a 2.9 m long girder structure with high eigenfrequencies,a high stiffness and a low *** on a topology optimisation result,a parametric beam–shell model including biologically inspired structures(e.g.,Voronoi combs,ribs,and soft and organic-looking transitions)was built *** subsequent cross-sectional optimisation using evolutionary strategic optimisation revealed an optimum girder structure,which was successfully manufactured using the casting *** measurements validated the numerical *** changes in the specifications can be implemented in the bio-inspired development process to obtain adapted girder structures.

关键词： Biomimetics Eigenfrequency maximisation Evolutionary structural optimisation Lightweight design Topology optimisation Voronoi combs

THE ROLE OF ADVANCED INTEGRATED FACADES IN THE DESIGN OF SUSTAINABLE BUILDINGS

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Journal of Green Building 2009年第1期4卷 76-98页

作者： Matthias Haase Inger andresen Tor Helge Dokka SINTEF Building and Infrastructure TrondheimNorway

1 BACKGROUND Sustainability issues have been the focus of building design for *** international agreements like the Kyoto protocol have pointed out the importance of reducing energy consumption related CO_(2)*** has become obvious that buildings consume a large amount of energy worldwide and thus bear the greatest potential for energy savings.

关键词： RATE greatest Kyoto

Active Thermal Control for Delaying Maintenance of Power Electronics Converters

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Chinese Journal of Electrical Engineering 2018年第3期4卷 13-20页

作者： Markus andresen Johannes Kuprat Vivek Raveendran Johannes Falck Marco Liserre Christian-Albrechts-Universität zu Kiel KielGermany

Several studies have reported about power semiconductors and capacitors being the most sensitive components in power *** lifetime of these devices is associated with the mission profile and the resulting temperature *** preventing failures,it is of interest to estimate the Remaining Useful Lifetime(RUL)and several condition monitoring methods have been proposed for this ***,modular power converters consist of a high number of components and methods have been proposed to reduce the thermal stress and therefore extend the lifetime of a system with software,referred to as active thermal *** power converters with limited accessibility,the RUL detected by the condition monitoring system may not fit to the scheduled maintenance of the system and devices may still have a significant RUL when their replacement is ***,this work proposes to control the stress of the most deteriorated components in the system such that the failure probability of multiple building blocks is equalized when the next maintenance is ***,this concept is proposed to extend the time to the next maintenance and reduce the number of maintenance instances without affecting the mean lifetime of the system.

关键词： Power electronics reliability condition monitoring active thermal control prognostic maintenance

Neoproterozoic basin evolution in Fennoscandia, East Greenland and Svalbard

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Episodes 2008年第1期31卷 35-43页

作者： Johan Petter Nystuen Arild andresen Risto A. Kumpulainen Anna Siedlecka Department of Geosciences University of Oslo Norway. Department of Geology and Geochemistry Stockholm University Sweden. Geological Survey of Norway Trondheim Norway.

Neoproterozoic successions of Fennoscandia, East Greenland and Svalbard are related to crustal extension and formation of sedimentary basins along the margins of northern Baltica （ Fennoscandia ） and eastern Laurentia （East Greenland and Svalbard）, preceding final break-up of Rodinia. The early rift stage （late Tonian-Cryogenian） is characterized by up to 16 km thick sedimentary successions of deep-marine sandstones and conglomerates linked to rift and strike-slip basins. Pericratonic basins expanded during Cryogenian-Cambrian coastal onlap. Cryogenian tropical climate is reflected by carbonate and evaporitic formations, most of which predate Cryogenian-Ediacaran glaciations. Glacial units, collectively referred to the Varanger Ice Age, may be equivalent to the Marinoan （c. 630 Ma） and the Gaskiers （c. 580 Ma） glacial periods. The final stage in break-up of Rodinia commenced with the emplacement of dolerite dyke swarms along the Baltoscandian margin at c. 600 Ma and the opening of the lapetus Ocean and other sea ways. No such dyke swarms have been recorded along the East Greenland segment of the Laurentian margin. Several Tonian-Cambrian tectonic and magmatic events recorded within the Kalak Nappe Complex in northern Finnmark make this unit an exotic terrane relative to the autochthonous Baltoscandian platform.

关键词：元古代盆地演化过程格陵兰岛芬诺斯坎底亚斯瓦尔巴特群岛

PROPOSAL OF A NORWEGIAN ZEB DEFINITION:ASSESSING THE IMPLICATIONS FOR DESIGN

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Journal of Green Building 2011年第3期6卷 133-150页

作者： I.Sartori T.H.Dokka Inger andresen 不详 NTNU Norwegian University of Science and TechnologyFaculty of Architecture and Fine ArtTrondheimNorway

Conceptually a Zero Emission Building(ZEB)is a building with greatly reduced energy demand and able to generate electricity(or other carriers)from renewable sources in order to achieve a carbon neutral ***,a clear and agreed definition of Zero Emission Building(ZEB)is yet to be achieved,both internationally and in ***,it is understood that both the definition and the surrounding energy supply system will affect significantly the way buildings are designed to achieve the ZEB goal.A formal definition of ZEB is characterized by a set of criteria that are:the system boundary,feeding-in possibilities,balance object,balancing period,credits,crediting method,energy performance and mismatch *** each criterion different options are available,and the choice of which options are more appropriate to define ZEBs may depend on the political targets laying behind the promotion of ZEBs,hence may vary from country to *** paper focuses on two of these criteria:energy performance and credits used to measure the ZEB *** each criterion different options are considered and the implications they have on the building design are *** case study is on a typical Norwegian single family *** is shown that for certain choices on the two criteria options,a paradoxical situation could *** using off-site generation based on biomass/biofuels,achieving the ZEB balance may be easier for high energy consuming buildings than for efficient *** is the exact opposite of what ZEBs are meant to promote:design of energy efficient buildings with on-site generation *** on how to avoid such a paradox are suggested.

关键词： ZEB definition design low energy passive house

Volume and surface effects on two-photonic and three-photonic processes in dry co-doped upconversion nanocrystals

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Nano Research 2022年第3期15卷 2362-2373页

作者： Bettina Grauel Christian Würth Christian Homann Lisa Krukewitt Elina andresen Janina Roik Sebastian Recknagel Markus Haase Ute Resch-Genger Federal Institute for Materials Research and Testing(BAM) Division 1.2 BiophotonicsRichard-Willstaetter-Str.1112489 BerlinGermany Federal Institute for Materials Research and Testing(BAM) Division 1.6 Inorganic Reference MaterialsRichard-Willstaetter-Str.1112489 BerlinGermany Institute of Chemistry of New Materials Department Biology/ChemistryUniversity OsnabrueckBarbarastr.749076 OsnabrueckGermany Department of Anesthesiology and Intensive Care Medicine University Medical Center RostockSchillingallee 3518057 RostockGermany

Despite considerable advances in synthesizing high-quality core/shell upconversion(UC)nanocrystals(NC;UCNC)and UCNC photophysics,the application of near-infrared(NIR)-excitable lanthanide-doped UCNC in the life and material sciences is still hampered by the relatively low upconversion luminescence(UCL)of UCNC of small size or thin protecting *** obtain deeper insights into energy transfer and surface quenching processes involving Yb^(3+) and Er^(3+) ions,we examined energy loss processes in differently sized solid core NaYF_(4) nanocrystals doped with either Yb^(3+)(YbNC;20%Yb^(3+))or Er^(3+)(ErNC;2%Er^(3+))and co-doped with Yb^(3+) and Er^(3+)(YbErNC;20%Yb^(3+) and 2%Er^(3+))without a surface protection shell and coated with a thin and a thick NaYF_(4) shell in comparison to single and co-doped bulk *** studies at 375 nm excitation demonstrate back-energy transfer(BET)from the ^(4)G_(11/2) state of Er^(3+) to the ^(2)F_(5/2) state of Yb^(3+),through which the red Er^(3+) ^(4)F_(9/2) state is efficiently *** power density(P)-dependent steady state and time-resolved photoluminescence measurements at different excitation and emission wavelengths enable to separate surface-related and volume-related effects for two-photonic and three-photonic processes involved in UCL and indicate a different influence of surface passivation on the green and red Er3+*** intensity and lifetime of the latter respond particularly to an increase in volume of the active UCNC *** provide a three-dimensional random walk model to describe these effects that can be used in the future to predict the UCL behavior of UCNC.

关键词： upconversion luminescence core/shell nanoparticles dopant concentration lifetime volume effect surface quenching