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Seasonal coolth storage system for residential buildings in Australia

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Journal of Central South University 2012年第3期19卷 740-747页

作者： t.lhendup l.Aye R.J.Fuller Renewable Energy and Energy Efficiency Group Department of Infrastructure EngineeringMelbourne School of EngineeringThe University of Melbourne

Night sky cooling is explored as an alternative to the conventional cooling technologies using fossil fuels. the night sky cooling method is based on the long wave radiation of unglazed collectors to the sky at night. An evaluation of the night sky cooling system is present for a residential building in three cities of Australia, namely Alice Springs, Darwin and Melbourne. the system comprises an unglazed flat plate solar collector integrated with borehole storage. It uses night sky radiation to reduce the temperature of the ground near to the boreholes. the system was simulated with tRNSYS, a transient simulation program. the simulation results for adequately sized systems show that night sky radiation is able to reduce the coolth storage borehole temperature and the proposed system is able to meet the cooling load of the residential building simulated in three locations. Borchole lengths of 270, 318 and 106 m are required for coolth storage with 90, 260 and 14 m2 collector area for heat rejection in Alice Springs, Darwin and Melbourne, respectively. At the 20th simulation year, the proposed system is able to achieve a system cooling coefficient of performance of 2.2 in Alice Springs, and 2.8 in Darwin and Melbourne.

关键词： night sky cooling borehole coolth storage unglazed solar collectors

Origin of extension twinning-mediated static recrystallization and unique parallel alignment of(0001) poles to transverse direction in Mg-3Al-0.4Mn(mass%) alloy sheet

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Journal of Magnesium and Alloys 2023年第9期11卷 3200-3213页

作者： t.Nakata C.Xu l.Geng S.Kamado Nagaoka University of technology 1603-1KamitomiokaNagaoka 940-2188Japan School of Materials Science and Engineering Harbin Institute of technology Harbin 150001China

the origin of unique parallel alignment of(0001) poles to transverse direction(tD) was investigated using Mg-3Al-0.4Mn(mass%)alloy sheets rolled with different process conditions. When rolling was performed with intermediate reheating, the alloy showed a sluggish static recrystallization(SRX) behavior during post-annealing, facilitating the nucleation and growth of statically recrystallized grains from extension twins. this resulted in the apparent texture component with the parallel alignment of the(0001) poles to the tD, and the sheet exhibited good ductility for both the rolling direction(RD) and tD. In contrast, continuous rolling without intermediate reheating led to the formation of severely deformed regions near double twins. SRX was promoted at such regions, forming a typical basal textural feature with weak RD-split of the(0001) poles. Although extension twins were formed after the continuous rolling, SRX was facilitated at the severely deformed regions with double twins, and the formation of the unique alignment of the(0001) poles to the tD was suppressed. the RD-split texture led to the large elongation to failure along the RD, while it along the tD decreased owing to the narrow distribution of the(0001)poles toward the tD, resulting in the in-plane anisotropy in ductility.

关键词： Magnesium Rolling twinning Static recrystallization texture

Preparation of stimuli-responsive nano-sized capsules based on cyclodextrin polymers with redox or light switching properties

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Nano Research 2016年第7期9卷 2070-2078页

作者： Ewelina Wajs thorbjorn t. Nielsen Kim l. larsen Alex Fragoso Nanobiotechnology & Bioanalysis Group Departament d'Enginyeria Quimica Universitat Rovira i Virgili Avinguda Paisos Catalans 26 43007 Tarragona Spain Department of Chemistry and Biosciences Aalborg University Frederik Bajers Vej 7H 9220 Aalborg SO Denmark

We report the preparation and encapsulation properties of stimuli-responsive nanocapsules, self-assembled by the noncovalent interactions of cyclodextrin- appended polymers （host） and complementary ferrocene or azobenzene carriers （guest）. the encapsulation process was significantly accelerated by applying （electro） chemical or light stimulus, enabling the easier and faster diffusion of guest molecules through the polymer layers. the nanocapsules were characterized by dynamic light scattering, confocal microscopy, ESEM, AFM, W-visible and fluorescence spectroscopy, and electrochemical techniques. the encapsulation and release properties of the nanocapsules were reversible and could be repeated several times, indicating that the prepared nanoassemblies are very stable.

关键词： nanocapsule cyclodextrin,ferrocene,azobenzene,stimuli-responsive materials,encapsulation

Nonlinear stability of functionally graded material(FGM)sandwich cylindrical shells reinforced by FGM stiffeners in thermal environment

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Applied Mathematics and Mechanics(English Edition) 2017年第5期38卷 647-670页

作者： D.V.DUNG N.t.NGA l.K.HOA Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam Faculty of Basic Science Military Logistic AcademyHanoi 100000Vietnam

In this paper, Donnell＇s shell theory and smeared stiffeners technique are improved to analyze the postbuckling and buckling behaviors of circular cylindrical shells of stiffened thin functionally graded material （FGM） sandwich under an axial loading on elastic foundations, and the shells are considered in a thermal environment. the shells are stiffened by FGM rings and stringers. A general sigmoid law and a general power law are proposed. thermal elements of the shells and reinforcement stiffeners are considered. Explicit expressions to find critical loads and postbuckling load-deflection curves are obtained by applying the Galerkin method and choosing the three-term approximate solution of deflection. Numerical results show various effects of temperature, elastic foundation, stiffeners, material and geometrical properties, and the ratio between face sheet thickness and total thickness on the nonlinear behavior of shells.

关键词： functionally graded material (FGM) stiffened cylindrical shell sandwich,thermal environment

A New troodontid Dinosaur from the lower Cretaceous Yixian Formation of liaoning Province,China

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 763-780页

作者： SHEN Caizhi l Junchang lIU Sizhao Martin KUNDRt Stephen l.BRUSAttE GAO Hailong Institute of Geology Chinese Academy of Geological Sciences Dalian Natural History Museum Department of Ecology Faculty of Natural SciencesComenius University Center for Interdisciplinary Biosciences Faculty of ScienceUniversity of Pavol Jozef afárik University of Edinburgh School of GeoSciences Institute of Geomechanics Chinese Academy of Geological Sciences

A new troodontid dinosaur, Daliansaurus liaoningensis gen. et sp. nov., is erected based on a nearly complete specimen from the lower Cretaceous Yixian Formation of Beipiao City, liaoning Province, China. this well preserved skeleton provides important new details of the anatomy for liaoning troodontids, and gives new insight into their phylogenetic relationships and evolution. Daliansaurus is distinguished from other troodontids by an enlarged ungual on pedal digit IV, which is approximately the same size as the sickle-shaped second ungual, and is differentiated from other liaoning troodontids by a number of characters of the skull, manus, pelvis, and hindlimb. A phylogenetic analysis recovers Daliansaurus within a subclade of liaoning troodontids that also includes Sinovenator, Sinusonasus, and Mel We erect a name for this group--Sinovenatorinae--and argue that it reflects a localized radiation of small-bodied troodontids in the Early Cretaceous of eastern Asia, similar to previously recognized radiations of liaoning dromaeosaurids and avialans. As more liaoning theropods are discovered, it is becoming apparent that small, feathered paravians were particularly diverse during the Early Cretaceous, and future work is needed to clarify how this diversity arose, which species coexisted, and how these numerous species partitioned niches.

关键词： troodontids Daliansaurus liaoningensis Early Cretaceous Yixian Formation liaoning

Numerical analysis of the effects of vesicle distribution characteristics on the engineering properties of volcanic rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3094-3104页

作者： P.l.P.Wasantha Z.Heng t.Xu College of Sport Health and EngineeringVictoria UniversityMelbourneVIC3011Australia Institute for Sustainable Industries and liveable Cities Victoria UniversityMelbourneVIC3011Australia Center for Rock Instability and Seismicity Research Northeastern UniversityShenyang110819China

Vesicles can be of different sizes and shapes and can be randomly distributed within vesicular volcanic rocks. this study investigates the variation of engineering properties of vesicular rocks due to the changes in vesicle distribution characteristics for different cases of bulk porosity and vesicle diameter using a systematic numerical simulation program using the finite element method-based rock failure process analysis (RFPA) software. Models with uniform-size vesicles and combinations of different proportions of different-sized vesicles were considered to resemble natural vesicular rocks more closely, and ten different random vesicle distributions were tested for each case. Increasing bulk porosity decreased the uniaxial compressive strength (UCS) and elastic modulus of the specimens, and the specimens with the lowest bulk porosity showed the greatest range of UCS values in the case of uniform-size vesicles. the effect of vesicle diameter on UCS showed an unsystematic response which was understood to be a result of different vesicle distribution patterns, some of which facilitated a shear failure. Specimens with multiple-size vesicles in different proportions revealed that the variation of UCS due to vesicle distribution characteristics is minimum when the bulk porosity is equally shared by different size vesicles. In addition, when the proportion of smaller-sized vesicles is higher, UCS showed an increase compared to that of the equal proportion of different size vesicles case at low porosities, but a decrease at higher porosities. Variation of elastic modulus showed minor, unsystematic fluctuations as a function of vesicle diameter and different proportions of different-sized vesicles, and the range for different vesicle distribution patterns was narrow in general. Overall, the findings of this study recommend cautious use of the engineering properties determined through a limited number of laboratory tests on vesicular rocks.

关键词： Vesicular rocks Porosity Vesicle size and distribution Numerical simulation Mechanical characteristics

Microstructure of Nitrided Aluminum Alloys Using an Electron-Beam-Excited-Plasma (EBEP)

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材料热处理学报 2004年第5期25卷 349-353页

作者： l.liu A.Yamamoto t.Hishida H.Shoyama t.Hara H.tsubakino GraduateSchool UniversityofHyogo2167ShoshaHimeji671-2201Japan FaultyofEngineering ToyotaTechnologicalInstituteNagoya468-8511Japan

Nitriding of surface of aluminum alloys was carried out with using an electron-beam-excited-plasma (EBEP) technique. the EBEP is sustained by electron impact ionization with energetic electron beam. two kinds of substrates, aluminum alloys AA5052 and AA5083, were exposed to the down flow of EBEP source at 843 K for 45min. the specimens were characterized with respect to following properties: crystallographic structure (XRD), morphology (SEM) and the cross sectional microstructures of the nitrided layer was observed using a scanning electron microscopy (SEM). there are some A12O3 particles on the surface of the nitrided AA5052 and AA5083. the A1N layers were formed on the substrates with the thickness of 4.5 fi m for AA5052 and 0.5 /z m for AA5083 . A relatively uniform nitrided surface layer composed of A1N can be observed on the AA5052 substrate. the grains size near the interfaces between the substrate and A1N layer were smaller than that near the surface. On the surface of A1N layer, the concentration of nitrogen was high and in the middle of A1N layer it had a constant concentration like the aluminum and the concentration was decreased with approaching to the interface. On the surface of nitrided AA5083, a uniform A1N layer was not formed as the reason for the high nitriding temperature.

关键词：显微结构铝合金渗氮 EBEP

Prediction of the flooding area of the northeastern Caspian Sea from satellite images

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Geodesy and Geodynamics 2023年第2期14卷 191-200页

作者： Anzhelika t.Kamza Irina A.Kuznetsova Eugene l.levin Satbayev University Almaty 050013Kazakhstan limited partnership"International Educational Corporation" Almaty 050043Kazakhstan School of Applied Computational Sciences Meharry Medical CollegeTennessee 37208USA

Studying the dynamic changes in the coastline of the northeastern Caspian Sea is significant since the level of the Caspian is unstable,and the coastline change can cause enormous damage to the ecology,economy,and population of the coastal part of *** this work,we use remote sensing and Geographic Information System(GIS)technologies to study the changes in the coastline of the northeastern Caspian Sea and predict the extent of flooding with increasing water *** proposed methodology for creating dynamic maps can be used to monitor the coastline and forecast the extent of flooding in the *** a result of this work,the main factors affecting changes in the coastline were *** analyzing the water level data from 1988 to 2019,it was revealed that the rise in water level was observed from 1980 to *** maximum sea level rise was recorded at-26.04 *** that,the sea level began to fall,and between 1996 and 2009,there were no significant changes;the water level fluctuated with an average of-27.18 ***,a map of the water level dynamics in the Caspian Sea from 1988 to 2019 was *** to the dynamics map,water level rise and significant coastal retreat were revealed,especially in the northern part of the Caspian Sea and the northern and southern parts of Sora *** method for predicting the estimated flooding area was *** a result,based on a single map,the flooding area of the northeast coast was predicted.A comparative analysis of landsat and SRtM data is presented.

关键词： Caspian Sea Seabed Earth remote sensing GIS landsat Prediction of the flooding area Ecology of coastline SRtM

li(2p←2s)+Na(3s)pressure broadening in the far-wing and line-core profiles

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Chinese Physics B 2022年第7期31卷 247-254页

作者： F talbi N lamoudi l Reggami M t Bouazza K Alioua M Bouledroua Physics Department Badji Mokhtar UniversityB.P.12Annaba 23000Algeria laboratoire de Physique des Rayonnements Badji Mokhtar UniversityB.P.12Annaba 23000Algeria laboratoire d’Etude des Surfaces et Interfaces de la Matiere Solide(lESIMS) Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria laboratoire lAMA Laboratoire des Materiaux Avances(LAMA)Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria laboratoire de Physique de la Matiere et du Rayonnement lPMR Universite Cherif MessaidiaB.P.1553Souk-Ahras 41000Algeria

this work reports pressure-broadening line-wing and line-core of the lithium li(2p←2s)resonance line perturbed by ground sodium Na(3s)*** far-wing regions,the calculations are performed quantum-mechanically and are intended to examine the photoabsorption coefficients at diverse *** results show the existence of three satellites,in the blue wing near the wavelengths 470 nm and in the red wing around 862 nm and 1070 *** the line-core region,by adopting the simplified Baranger model,the line-width and line-shift rates are determined,and their variation law with temperature is *** published data were found to compare these results with.

关键词： pressure broadening line-core broadening far-wing spectra photoabsorption