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effect of excitation wavelength(blue vs near UV)and dopant concentrations on afterglow and fast decay of persistent phosphor SrAl_(2)O_(4):eu^(2+),Dy^(3+)

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Journal of Rare earths 2022年第7期40卷 1022-1028页

作者： Bernhard Walfort Nando Gartmann Jafar Afshani Arnulf Rosspeintner hans Hagemann LumiNova AG SwitzerlandSpeicherstrasse 60aCH-9053TeufenSwitzerland Dépt.de Chimie Physique Universitéde Genève30Quai E.AnsermetCH 1211Geneva 4Switzerland

The persistent phosphor SrAl_(2)O_(4):eu^(2+),Dy^(3+)is the subject of numerous *** often neglected aspect is that in this phosphor,as well as in Sr_(4)Al_(14)O_(25):eu^(2+),Dy^(3+),there are two different Sr^(2)+sites which can be occupied by the dopant eu^(2+)ions,We first introduce a general scheme of possible energy transfers in these persistent phosphor materials including explicitly both europium ions,This scheme is used as a generic starting point to study experimentally specific *** illustrate this application with the study of the effect of excitation wavelength(444 and 382 nm)on the afterglow of differently doped SrAl_(2)O_(4):eu^(2+),Dy^(3+)samples,as well as on the emission decay *** the same excitation intensity under 444 nm excitation,the resulting afterglow intensity is stronger than under near UV *** 382 nm,eu^(2+)ions on both Sr^(2)+s ites in SrAl_(2)O_(4)are excited,but at room temperature the blue emission is quenched,leading to a loss of *** observed effects can further be associated with the ratio of eu^(2+)ions and trap states which are modulated by the concentrations of eu^(2+)and Dy^(3+)in SrAl_(2)O_(4),as well as by temperature,Increasing the nominal Dy^(3+)content from 0.1 mol%to 0.5 mol%with respect to Sr results in the doubling of the integrated afterglow intensity and confirms thus that Dy^(3+)ions are indeed involved in the trapping process,The concentration of trap states is much lower than the concentration of eu^(2+)ions,as even with low excitation densities,a plateau of integrated afterglow intensity(corresponding to the total number of accessible traps)is *** postulate that an important fraction of excited eu^(2+)ions can potentially transfer their energy to trap *** that all traps are filled or in a dynamical filling-depletion process under illumination(with thermal and/or optical depletion processes),for the remaining eu^(2+)a"normal"steady-state emission is observed

关键词： Persistent phosphor Strontium aluminate europium Forster energy transfer Rare earths

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Ground-based and additional science support for SMILe

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earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter M.Dunlop C.Forsyth K.Oksavik e.Donovon A.Kavanagh S.e.Milan T.sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.James L.Juusola K.Kauristie e.A.Kronberg M.Lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae L.Ren F.Sigernes e.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton Laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and environment Beihang UniversityBeijing 100191China Key Laboratory of Space environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada eSTeC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China Finnish Meteorological Institute(FMI) Finland Department of earth and environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GFZ German Research Centre for Geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint european Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link explorer(SMILe)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILe ***,we describe current community efforts to prepare for SMILe,and the benefits and context various experiments that have explicitly expressed support for SMILe can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SMILe Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMILe mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMILe conjunctions missions

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Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Advances in Atmospheric Sciences 2024年第8期41卷 1559-1568页

作者： Astrid e.J.OGILVIe Leslie A.KING Noel KeeNLYSIDe François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels eINARSSON sergey GULeV Ke FAN Torben KOeNIGK James R.MCGOODWIN Marianne H.RASMUSSON Shuting YANG Institute of Arctic and Alpine Research(INSTAAR) University of ColoradoBoulder CO 80303USA Stefansson Arctic Institute AkureyriÍS-600Iceland Royal Roads University BC V9B 5Y2Canada University of Bergen Bergen N-5007Norway Nansen environmental and Remote sensing Centre Bergen N-5007Norway University of Iceland Reykjavík 102Iceland Shirshov Institute of Oceanology Moscow 117218Russia Moscow State University Moscow 11991Russia Chinese Academy of Sciences Beijing 100045China Swedish Meteorological and Hydrological Institute SE-60176 NorrköpingSweden Danish Meteorological Institute CopenhagenØ2100Denmark Obukhov Institute of Atmospheric Physics RAS119017MoscowRussia

This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATH(https://***/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATH made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATH was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATH served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities.

关键词： Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Multimodal pain stimulation of the gastrointestinal tract

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World Journal of Gastroenterology 2006年第16期12卷 2477-2486页

作者： Asbjφrn Mohr Drewes hans Gregersen Center for Biomechanics and Pain Department of GastroenterologyAalborg Hospital & Center for Sensory-Motor Interactions (SMI)Department of Health Science and TechnologyAalborg UniversityAalborgDenmark Center for Biomechanics and Pain Department of GastroenterologyAalborg Hospital

Understanding and characterization of pain and other sensory symptoms are among the most important issues in the diagnosis and assessment of patient with gastrointestinal disorders. Methods to evoke and assess experimental pain have recently developed into a new area with the possibility for multimodal stimulation （e.g., electrical, mechanical, thermal and chemical stimulation） of different nerves and pain pathways in the human gut. Such methods mimic to a high degree the pain experienced in the clinic. Multimodal pain methods have increased our basic understanding of different peripheral receptors in the gut in health and disease. Together with advanced muscle analysis, the methods have increased our understanding of receptors sensitive to mechanical, chemical and temperature stimuli in diseases, such as systemic sclerosis and diabetes. The methods can also be used to unravel central pain mechanisms, such as those involved in allodynia, hyperalgesia and referred pain. Abnormalities in central pain mechanisms are often seen in patients with chronic gut pain and hence methods relying on multimodal pain stimulation may help to understand the symptoms in these patients. sex differences have been observed in several diseases of the gut, and differences in central pain processing between males and females have been hypothesized using multimodal pain stimulations. Finally, multimodal methods have recently been used to gain more insight into the effect of drugs against pain in the GI tract. Hence, the multimodal methods undoubtedly represents a major step forward in the future characterization and treatment of patients with various diseases of the gut.

关键词： Pain Gut experimental Allodynia Hyperalgesia Neurophysiology

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The Role of Stationary and Transient Planetary Waves in the Maintenance of Stratospheric Polar Vortex Regimes in Northern Hemisphere Winter

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Advances in Atmospheric Sciences 2011年第1期28卷 187-194页

作者：李倩 hans-F.GRAF 崔雪锋 Key Laboratory of Middle Atmosphere and Global environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences School of GeoSciences University of Edinburgh Center for Atmospheric Science University of Cambridge State Key Laboratory of earth Surface Processes and Resource ecology College of Global Change and Earth System ScienceBeijing Normal University

Using 1958-2002 NCePNCAR reanalysis data, we investigate stationary and transient planetary wave propagation and its role in wave-mean flow interaction which influences the state of the polar vortex （PV） in the stratosphere in Northern Hemisphere （NH） winter. This is done by analyzing the eliassen-Palm （e-P） flux and its divergence. We find that the stationary and transient waves propagate upward and equatorward in NH winter, with stronger upward propagation of stationary waves from the troposphere to the stratosphere, and stronger equatorward propagation of transient waves from mid-latitudes to the subtropics in the troposphere. Stationary waves exhibit more upward propagation in the polar stratosphere during the weak polar vortex regime （WVR） than during the strong polar vortex regime （SVR）. On the other hand, transient waves have more upward propagation during SVR than during WVR in the subpolar stratosphere, with a domain of low frequency waves. With different paths of upward propagation, both stationary and transient waves contribute to the maintenance of the observed stratospheric PV regimes in NH winter.

关键词： stratospheric polar vortex planetary waves stationary transient

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恶性间皮瘤29例分析

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中国肿瘤临床 1991年第4期18卷 227-229页

作者：周晓南 hans.,e 宁夏医学院

本文回顾加拿大金斯顿总医院从1950～1987年经组织活检或尸检证实的恶性间皮瘤死亡病例29人,发现该病逐年增长,男与女之比为3:1,胸膜间皮瘤与腹膜间皮瘤之比亦为3:1,近半数患者年龄为50～59岁。胸膜间皮瘤的初始症状为气短、胸痛、咳嗽... 详细信息

本文回顾加拿大金斯顿总医院从1950～1987年经组织活检或尸检证实的恶性间皮瘤死亡病例29人,发现该病逐年增长,男与女之比为3:1,胸膜间皮瘤与腹膜间皮瘤之比亦为3:1,近半数患者年龄为50～59岁。胸膜间皮瘤的初始症状为气短、胸痛、咳嗽和体重减轻,胸片表现为胸腔积液、块影和胸膜增厚,原发灶约2/3在右侧。腹膜间皮瘤主要表现为腹块、腹痛及腹水,预后较胸膜间皮瘤更差。手术组预后略好,其他各治疗组与未治组的存活时间无显著性差异。分析各组患者确诊时的一般状况、接受治疗者所承担的风险、痛苦及花费,建议今后对已确诊的恶性间皮瘤病人,特别是Ⅱ期以上患者,在未有更有效疗法前,均可停止治疗,任其安乐死亡。

关键词：恶性间皮瘤胸膜腹膜预后

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Pacing and predictors of performance during cross-country skiing races:A systematic review

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Journal of Sport and Health Science 2018年第4期7卷 381-393页

作者： Thomas Stogg Barbara Pellegrini hans-Christer Holmberg Department of Sport and exercise Science University of SalzburgHallein/Rif 5400Austria CeRiSM Research Centre＂Sport Mountainand Health＂Rovereto 36068Italy Department of Neuroscience Biomedicine and MovementUniversity of VeronaVerona 37100Italy Swedish Winter Sports Research Centre Mid Sweden UniversityOstersund 83128Sweden School of Sport Sciences UiT Arctic University of NorwayTroms（）9037Norway School of Kinesiology University of British ColumbiaVancouverBC V6T 121Canada Department of Physiology and Pharmacology Karolinska InstitutetStockhol 17177Sweden Corresponding author.e-mail address：thomas.stoeggl@sbg.ac.at

Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the english language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single d

关键词： Classic style Competition Cycle characteristics Positive pacing Skating

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The pairwise velocity difference of over 2000 BHB stars in the Milky Way halo

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Research in Astronomy and Astrophysics 2009年第11期9卷 1230-1240页

作者： Xiang-Xiang Xue hans-Walter Rix Gang Zhao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Max-Planck-Institute for Astronomy Konigstuhl 17 D-69117 Heidelberg Germany Graduate University of Chinese Academy of Sciences Beijing 100049 China

Models of hierarchical galaxy formation predict that the extended stellar halos of galaxies like our Milky Way show a great deal of sub-structure, arising from disrupted satellites. Spatial sub-structure is directly observed, and has been quantified, in the Milky Way＇s stellar halo. Phase-space conservation implies that there should be sub-structure in position-velocity space. Here, we aim to quantify such position-velocity sub-structure, using a state-of-the art data set having over 2000 blue horizontal branch （BHB） stars with photometry and spectroscopy from SDSS. For stars in dynamically cold streams （＂young＂ streams）, we expect that pairs of objects that are physically close also have similar velocities. Therefore, we apply the well-established ＂pairwise velocity difference＂（PVD） statistic （｜ △Vlos ｜）（△r）, where we expect （｜ △Vlos ｜） to drop for small separations At. We calculate the PVD for the SDSS BHB sample and find 〈｜ △Vlos ｜〉（△r） ≈ const., i.e. no such signal. By making mock-observations of the simulations by Bullock ＆ Johnston and applying the same statistic, we show that for individual, dynamically young streams, or assemblages of such streams, （｜ △Vlos ｜） drops for small distance separations At, as qualitatively expected. However, for a realistic complete set of halo streams, the pair-wise velocity difference shows no signal, as the simulated halos are dominated by ＂dynamically old＂ phase-mixed streams. Our findings imply that the sparse sampling and the sample sizes in SDSS DR6 are still insufficient to use the position-velocity sub-structure for a stringent quantitative data-model comparison. Therefore, alternate statistics must be explored and much more densely sampled surveys, dedicated to the structure of the Milky Way, such as LAMOST, are needed.

关键词： cosmology dark matter-- galaxies individual (Milky Way) -- galaxy halo -- stars horizontal-branch- stars kinematics

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Heat Transfer and Hydrodynamics in Annular Chromatography: CFD-Simulation and experiments

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Journal of Thermal Science 2000年第2期9卷 129-134页

作者： hans－JoergBart JorgBrozio 等 UniversitaetKaisersautern LehrstuhifuerThermischeVerfachrenstechnikPostfach3049D－67653KaiserslauternGermanyE－amil：bart@mv.uni－kl.de UniversitaetKaisersautern LehrstuhifuerThermischeVerfachrenstech

Continuous annular chromatography(CAC) is a separation process for multicomponent liquid mixtures. The performance of the apparatus can be seriously decreased by temperature gradients inside the adsorbent bed. It is shown, that the temperature gradients can be significantly reduced by a pre-heating of the entering liquid in the apparatus itself. Heat transfer and hydrodynamics in the porous media are described by two different modelling approaches. Both are based on a pseudo-homogeneous model for heat transfer with temperature dependent fluid viscosities. The first model considers one-dimensional fluid now and two-dimensional heat transfer. The second, more rigorous one is a three-dimensional model for heat transfer and hydrodynamics. The simulation results obtained with both models are in good agreement with experimental results. The experiments have been performed with glass beads as the stationary phase and water as the liquid phase under different boundary conditions. The temparature profiles inside the packed bed have been measured with thermocouples.

关键词： porous media numerical heat transfer chromatography computational fluid dynamics.

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Solubility Product of Ni-Struvite, NH4NiPO4·6H2O, at 25°C

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Advances in Chemical engineering and Science 2017年第2期7卷 206-214页

作者： hans e. Lundager Madsen Chemistry Department University of Copenhagen Copenhagen Denmark

Solubility product of a sparingly soluble salt is an important parameter in both pure and applied physical chemistry such as determination of values of thermodynamic functions or environmental implications of components of the substance. This paper presents the determination of the solubility product of ammonium nickel phosphate hexahydrate (Ni-struvite) at 25°C by analysis of equilibria attained from both supersaturated and undersaturated solutions, i.e. precipitation and dissolution, respectively. Writing the dissolution process as NH4NiPO4·6H2O → NH3 + Ni2+ ++ 6 H2O, the value pKsp = 11.03 ± 0.03 is found for both precipitation and dissolution. The solubility is a little lower than that of the isomorphous Mg salt. This is to be expected from the lattice dimensions of the two phases, the crystals of Ni-struvite being slightly more compact.

关键词： Ammonium Nickel Phosphate Ni-Struvite Solubility Product

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