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Photoluminescence and Electroluminescence Studies on Tb-Doped Silicon Rich Oxide Materials and Devices

Journal of Rare Earths 2006年第6期24卷 673-678页

作者： Yoshi Ono Sheng-Teng Hsu Sharp Labs of America 5750 N.W. Pacific Rim Blvd. Camas Washington 98607USA

Photoluminescence （PL） characteristics of Tb-doped silicon rich oxide （SRO） films prepared by DC-sputtering and post-annealing processes were studied. The silicon richness of the SRO film could be controlled by varying the sputtering power and oxygen concentration in the sputtering chamber. PL emission from the as-deposited sample was found to be composed of Th^3 ＋ intra 4f transition-related emission and the silicon nano particle-related broad bandwidth emission. Thermal annealing could significantly improve the material properties as well as the PL signals. PL properties depended strongly upon the annealing scheme and silicon richness. Annealing at high temperatures （900- 1050℃） enhanced Tbrelated emission and suppressed the silicon nano particle-related emission. For samples with different silicon richness, annealing at 950 ℃ was found to produce higher PL signals than at other temperatures. It was attributed more to lifetime quenching than to concentration quenching. Electroluminescent （EL） devices with a capacitor structure were fabricated, the optimized process condition for the EL device was found to be different from that of PL emission. Among the annealing schemes that were used, wet oxidation was found to improve device performance the most, whereas, dry oxidation was found to improve material property the most. wet oxidation allowed the breakdown electrical field to increase significantly and to reach above 10 mV·cm^-1. The EL spectra showed a typical Th^3＋ emission, agreeing well with the PL spectra. The I-V measurements indicated that for 100 nm thick film, the Fowler-Nordheim tunneling started at an electrical field of around 6 mV·cm^-1 and the light emission became detectable at a current density of around 10-4 A·cm^-2 and higher. Strong electroluminescence light emission was detected when the electrical field was close to 10 mV·cm^-1.

关键词： electroluminescence device silicon rich oxide rare earths

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A Spatio-Temporal Odyssey Around the Concepts of Sustainable Development and Corporate Social Responsibility： Boundaries to Be Determined？

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Journal of Modern Accounting and Auditing 2011年第10期7卷 1158-1168页

作者： Azzedine Tounes wafa Chakroun Fafani Gribaa groupe ESC Chambery Savoie France Sousse University Tunisia Montpellier 1 University France

The aim of this research is to analyze the emergence of the concepts of sustainable development （SD） and corporate social responsibility （CSR） in companies in time and space. A spatio-temporal reading will indicate the most important socio-political and environmental events that have emerged with these two concepts. In order to complete the odyssey, a spatio-temporal analysis has retraced the epistemological evolution of these latter, whilst at the same time remarking the appropriation that has been made by the different institutional and organizational actors. The historical and epistemological reviews tell us that these two concepts, which came into existence almost 80 years, have indefinite outlines; one can be substituted for the other. However, thanks to this odyssey, we have reduced the boundaries even further between sustainable development and social responsibility and shown their theoretic and historical association. The perspective adopted shows that the concept of corporate social responsibility is closely connected to that of sustainable development. This connection means that researchers in management science are faced with more new problem issues reaching further than the simple lack of conceptual consensuses.

关键词： corporate social responsibility eco-development spatio-temporal analysis sustainable development

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Simulating hydrodynamics of hot and large Group A particle systems at cold conditions to obtain data for scale-up

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Particuology 2010年第6期8卷 501-502页

作者： Ted M.Knowlton Particulate Solid Research Inc.4201 W.36th StreetChicagoILUSA

Scaling laws based on the concept of dimensional similitude are proposed to simulate the hydrodynamics of hot and large particle systems at conditions of cold and small particle systems. This technique uses the concept of dimensional similitude to accomplish this by maintaining certain dimensional groups constant in the large, hot and small, cold systems. However, there are certain limitations with this technique. One of them is that the particle size in the small, cold system is usually smaller than in the large, hot system. Because particle size is such a dominant parameter in fluidized systems, this can certainly affect the simulation. An alternative method of simulating hot hydrodynamics in ambient-temperature Group A particle systems has been proposed. In this method, the same calculated drag force is maintained between the two systems. The drag force is varied by changing the gas density of the cold system so that it matches the drag force in the hot system.

关键词： Drag Drag force Simulation Modeling

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Middle Ordovician Conodont Biostratigraphy of Australasia

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Journal of Earth Science 2021年第3期32卷 474-485页

作者： Yong Yi Zhen w.B.Clarke Geoscience Centre Geological Survey of New South WalesLondonderry NSW 2753Australia

Seven conodont biozones are recognized in the carbonate-dominated shelf-marine Middle Ordovician developed in the intracratonic sedimentary basins(Canning,Amadeus and Georgina)of central and north-western Australia,in the Lachlan and New England orogens of New South wales,and in the Takaka Terrane of New Zealand.A separate scheme identifying seven conodont biozones spanning the Middle Ordovician has also been developed for siliciclastic sequences deposited in slopebasinal environments in the Lachlan Orogen in New South wales and *** biozonal classification consisting of two parallel biostratigraphic schemes for the shelf-marine and deep-marine successions respectively has significantly increased precision in regional and global biostratigraphic correlation and laid a solid foundation for the Middle Ordovician chronostratigraphy of Australia and New *** of short-ranging pandemic species as the eponymous species of the biozones also supports direct correlation with the classical conodont successions established in Baltoscandia and the North American Midcontinent,and with those of the major Chinese terranes(South and North China and Tarim).The Lachlan Orogen appears to be globally unique in enabling correlation of contemporaneous conodont faunas over a considerable spectrum of water depths and biofacies ranging from carbonate shelves,slopes to deep-water basins.

关键词： conodont Ordovician correlation Australia New Zealand

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Quantifying growth and breakage of agglomerates in fluid-particle flow using discrete particle method

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Chinese Journal of Chemical Engineering 2018年第5期26卷 914-921页

作者： Lingfeng Zhou Junwu wang wei Ge Shiwen Liu Jianhua Chen Ji xu Limin wang Feiguo Chen Ning Yang Rongtao Zhou Lin Zhang Qi Chang Philippe Ricoux Alvaro Fernandez State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Tianjin University Tianjin 300072 China TOTALSA - R&D groupe Paris 92069 France Total Research & Technology Feluy Belgium Germany

The cohesive solids in liquid flows are featured by the dynamic growth and breakage of agglomerates, and the difficulties in the development, design and optimization of these systems are related to this significant *** this paper, discrete particle method is used to simulate a solid–liquid flow system including millions of cohesive particles, the growth rate and breakage rate of agglomerates are then systematically investigated. It was found that the most probable size of the agglomerates is determined by the balance of growth and breakage of the agglomerates the cross point of the lines of growth rate and breakage rate as a function of the particle numbers in an agglomerate, marks the most stable agglomerate size. The finding here provides a feasible way to quantify the dynamic behaviors of growth and breakage of agglomerates, and therefore offers the possibility of quantifying the effects of agglomerates on the hydrodynamics of fluid flows with cohesive particles.

关键词： Agglomerate Growth and breakage Quantification Discrete particle method

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Alloying metal cations in perovskite nanocrystals is a new route to controlling hot carrier cooling

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Light(Science & Applications) 2023年第12期12卷 2535-2537页

作者： Navendu Mondal Ben P.Carwithen Artem A.Bakulin Department of Chemistry and Centre for Processable Electronics Imperial College LondonLondon W120BZUK

Hot carrier cooling is slowed down upon alloying tin in lead-halide perovskite nanocrystals through the engineering of carrier-phonon and carrier-defect interactions.

关键词： alloying Alloying perovskite

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SINGULAR LIMITS FOR INHOMOGENEOUS EQUATIONS OF ELASTICITY

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Acta Mathematica Scientia 2009年第3期29卷 645-649页

作者：陆云光 Christian Klingenberg Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016 China Department of Mathematics National University of ColombiaBogota Colombia Mathematisches Institut Universitt Würzburg Am Hubland 97074 Würzburg Germany

Based on the framework introduced in [4] or [5], the singular limits of stiff relaxation and dominant diffusion for the Cauchy problem of inhomogeneous equations of elasticity is studied. we are able to reach equilibr... 详细信息

关键词： relaxation limit equations of elasticity compensated compactness invariantregions theory

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The role of tree uprooting in the transporting of sediment and mixing of soil in the Tatra Mountains

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Journal of Mountain Science 2021年第1期18卷 38-50页

作者： Dariusz STRZYŻOwSKI Institute of Geography and Spatial Management Jagiellonian UniversityGronostajowa 7Kraków 30-387Poland

Tree uprooting is an important process which leads to many geomorphic *** of the most important are the transport of sediment and mixing of *** aim of this article is to make a detailed examination of the magnitude of sediment transport caused by an extreme windthrow event in three severely affected ***,a comparison is made of the windthrow event with a mass movement event in the aspect of the magnitude of sediment transport and soil *** study was conducted in three second-to third-order catchments in the Tatra Mountains,where a strong foehn wind event caused extensive windthrow in 2013,and a high-magnitude rainfall event triggered mass movements in *** volume of sediment uplifted by the uprooting event was calculated based on the mapping of root plates using high-resolution(0.04 m)aerial images and measurements of root plate volumes conducted in the *** volume of sediment transported by shallow landslides was determined based on a Digital Elevation Model(DEM1-m resolution).windthrows affected 34%,76%,and94%of the area of the investigated *** of the trees had fallen *** direction of treefall was influenced by the slope aspect and *** plates and pits covered 1.3%,4.8%,and 5.4%of the area of the *** flux generated by the uprooting event,calculated for the entire area of each investigated catchment ranged from 8.1×10^(–4) to 9.9×10^(–3) m^(3) m^(–1) event^(–1).This was notably lower than the sediment flux generated by the mass movement event(also calculated for the entire area of each catchment),which was 1.8-6.1×10^(–2)m^(3) m^(–1) event^(–1).By contrast,uprooting affected a much larger area than the mass movement event,which underlines its significant role in the mixing of soil.

关键词： Tree uprooting windthrow event Slope processes Sediment flux Tatra Mountains

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The intensity of slope and fluvial processes after a catastrophic windthrow event in small catchments in the Tatra Mountains

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Journal of Mountain Science 2021年第6期18卷 1405-1423页

作者： Dariusz STRZYŻOwSKI Elżbieta GORCZYCA Kazimierz KRZEMIEŃ Mirosław ŻELAZNY Institute of Geography and Spatial Management Jagiellonian UniversityGronostajowa 7Kraków 30-387Poland

Strong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second-to third-order catchments with area ranging from 0.09 km^(2) to 0.8 km^(2). Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. we mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. we also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small(total area w landslides were created. The mean distance of bedload transport was similar(t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.

关键词： Fluvial processes Slope processes windthrow Tree uprooting Channel morphology Tatra Mountains

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Integrity of the pancreatic duct-acinar system in the pathogenesis of acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2010年第3期9卷 242-247页

作者： wang, Guo-Jun Li, Yuan Zhou, Zong-Guang wang, Cun Meng, wen-Jian Sichuan Univ W China Hosp Inst Digest Surg Chengdu 610041 Peoples R China Sichuan Univ W China Hosp Dept Gen Surg Chengdu 610041 Peoples R China

BACKGROUND: Acute pancreatitis is an acute inflammatory process of the pancreas that frequently involves peripancreatic tissues and at times remote organ systems. For a long time, the etiology and pathogenesis of acute pancreatitis has been intensively investigated worldwide, but the pathogenetic theories are controversial. The integrity of the pancreatic duct-acinar system might play an important role in the pathogenesis of this disease. DATA SOURCES: web of Science and PubMed databases were searched for published studies (between January 1966 and June 2009) to identify relevant articles using the keywords 'acinar hyperstimulation', 'pathogenesis', 'acute pancreatitis', 'pancreatic duct-acinar system', and 'pancreatic duct pressure'. Most of the relevant articles were reviewed. RESULTS: From critical reading of the relevant articles, we found that the underlying mechanisms involved in the pathogenesis of acute pancreatitis are still under debate and ill-understood. On the basis of the relevant studies, we propose a hypothesis for the pathogenesis of acute pancreatitis, in which the integrity of the pancreatic duct-acinar system plays an essential role in the onset and progression of various forms of the disease. CONCLUSIONS: In our hypothesis, pancreatic duct obstruction and hyperstimulation of the exocrine pancreas are preconditions for the onset of acute pancreatitis; under the common conditions of pancreatic duct obstruction and acinar hyperstimulation, acute pancreatitis arises and develops. This may be an important common pathophysiological mechanism causing various forms of acute pancreatitis. (Hepntobiliary Pancreat Dis Int 2010; 9: 242-247)

关键词： pancreatic duct-acinar system pathogenesis acute pancreatitis acinar hyperstimulation pancreatic duct pressure

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