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International Journal of Digital Earth 2023年第1期16卷 1205-1223页

作者： Mohammad Mansourmoghaddam Iman Rousta Haraldur Olafsson Przemysław Tkaczyk Stanisław Chmiel Piotr Baranowski Jaromir Krzyszczak Center for Remote Sensing and GIS studies Shahid Beheshti UniversityTehranIran Department of Geography Yazd UniversityYazdIran Institute for Atmospheric Sciences-Weather and Climate University of IcelandReykjavikIceland Department of Agricultural and Environmental Chemistry University of Life SciencesLublinPoland Department of Hydrology and Climatology Institute of Earth and Environmental SciencesMaria Sklodowska-Curie UniversityLublinPoland Institute of Agrophysics Polish Academy of SciencesLublinPoland

Carbon Monoxide(CO)is an important urban pollutant with a relation to 5,transition economies based on emission *** this study,Sentinel-MODerate resolution Imaging Spectroradiometer(MODIS),and Landsat-8 images were used to investigate the variations of CO and urban environmental indices and the correlations between *** the assessed correlations for 932 Iranian cities,it occurred that the assessed indices were all *** highest CO levels were 0.031 in the spring of 2019 and 2020,whereas in 2021 it was equal to 0.030 in both the spring and winter,*** 2019 and 2020 the maximum values of the Enhanced Vegetation Index(EVI)in the spring were 0.181 and *** high Absorbing Aerosol Index(AAI)values of–0.834 and–1.0,along with Urban Index(UI)of 0.102 and 0.092,were correlated with recorded spikes in CO level,despite that these seasons’EVI values were not so *** was forecasted that in 2030 rises in the CO level by 13.2%in the winter and by 17.5%in the fall are expected,with the simultaneous increase of AAI by 204.5%and 980.2%,and Aerosol Optical Depth(AOD)by 27%and 5%in the winter and spring,respectively.

关键词： Urban pollutants enhanced vegetation index urban index absorbing aerosol index aerosol optical depth

Ⅲ-Ⅴ semiconductor nanocrystal formation in silicon nanowires via liquid-phase epitaxy

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Nano Research 2014年第12期7卷 1769-1776页

作者： Slawomir Prucnal Markus Glaser Alois Lugstein Emmerich Bertagnolli Michael Stoger-Pollach Shengqiang Zhou Manfred Helm Denis Reichel Lars Rebohle Marcin Turek Jerzy Zuk Wolfgang Skorupa Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-Rossendorf P.O. Box 510119 Dresden 01314 Germany Institute of Solid State Electronics Vienna University of Technology Floragasse 7 Vienna 1040 Austria USTEM Vienna University of Technology Wiedner HauptstraBe 8-10 Vienna 1040 Austria Center for Advancing Electronics Dresden Technische Universitat Dresden Dresden 01062 Germany maria curie-sklodowska university PL M. Curie-Sklodowskiej 1 Lublin 20-035 Poland

Direct integration of high-mobility III-V compound semiconductors with existing Si-based complementary metal-oxide-semiconductor （CMOS） processing platforms presents the main challenge to increasing the CMOS performance and the scaling trend. Silicon hetero-nanowires with integrated III-V segments are one of the most promising candidates for advanced nano-optoelectronics, as first demonstrated using molecular beam epitaxy techniques. Here we demonstrate a novel route for InAs/Si hybrid nanowire fabrication via millisecond range liquid-phase epitaxy regrowth using sequential ion beam implantation and flash-lamp annealing. We show that such highly mismatched systems can be monolithically integrated within a single nanowire. Optical and microstructural investigations confirm the high quality hetero-nanowire fabrication coupled with the formation of atomically sharp interfaces between Si and InAs segments. Such hybrid systems open new routes for future high-speed and multifunctional nanoelectronic devices on a single chip.

关键词： liquid phase epitaxy InAs hetero-nanowires silicon ion implantation

Assessing discharge periodicity in mountain catchments using classified environmental conditions(Tatra Mountains, Poland)

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Journal of Mountain Science 2022年第1期19卷 16-32页

作者： BOROWSKA-PAKUŁA Joanna MIĘSIAK-WÓJCIK Katarzyna Department of Hydrology and Climatology Institute of Earth and Envronmental ScienceMaria Curie-Skłodowska UniversityAleja Kraśnicka 2D20-031 LublinPoland

The periodicity of a river expressed in cycles of various lengths(monthly, seasonal,multiannual) is a result of climatic factors and overlapping environmental conditions within its catchment. In uncontrolled or poorly surveyed catchments, it is very difficult to determine the duration of a stream’s hydrological activity. This is especially relevant for catchments with complicated water circulation in karstic rocks. The present study concerns the small catchment of the Str??yski Potok river located in the area of the Tatra National Park, in the Western Tatras. The observation period covered the 2015 hydrological year, which differed hydrologically from average conditions. This study aims to develop a simple method to explain the processes shaping the mountain stream discharge periodicity. The research employed periodic field observations linked with climatic and non-climatic factors. Environmental conditions were assessed as four classes reflecting their influence on appearance or disappearance of mountain stream water. Class boundaries were the values of quartiles. The degree of correspondence between environmental factors and stream field observations was described via the Index DC(Degree Correspondence Index) *** correspondence(Index DC =0) was found in 23% catchments, a weak relationship between conditions favouring discharge and actual condition(Index DC=-1, +1) was noted within 11 catchments,while in 9 catchments, no such relationship was found(Index DC =-2, +2). The obtained results indicate a correspondence or lack thereof between the environmental potential of the catchment and its discharge periodicity. The discrepancies between the assessment of the influence of climatic and nonclimatic factors and the data collected during field observations provide a basis for more detailed *** of these studies based on the proposed classifications will allow for a more complete explanation of water disappearance in river channels and the d

关键词： Discharge periodicity Small mountain catchment Tatra Mountains Environmental analysis

Ultrabroadband wavelength-swept source based on total mode-locking of an Yb:CaF_(2)laser

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Photonics Research 2019年第2期7卷 182-186页

作者： MACIEJ KOWALCZYK TADEUSZ MARTYNKIEN PAWEL MERGO GRZEGORZ SOBON JAROSLAW SOTOR Laser & Fiber Electronics Group Faculty of ElectronicsWroclaw University of Science and Technology Department of Optics and Photonics Faculty of Fundamental Problems of TechnologyWroclaw University of Science and Technology Laboratory of Optical Fiber Technology Maria Curie-Sklodowska University

We present an ultrabroadband, high-speed wavelength-swept source based on a self-modulated femtosecond oscillator. Photonic crystal fiber was pumped by a mode-locked Yb:CaF2 laser, resulting in a strong spectral broadening from 485 to 1800 nm. The pump laser cavity could be realigned in order to achieve total mode-locking of the longitudinal and transverse TEM00 and TEM01 electromagnetic modes. This led to spatial oscillations of the output beam, which induced modulation of the coupling efficiency to the fiber. Due to the fact that nonlinear spectral broadening was intensity dependent, this mechanism introduced wavelength sweeping at the fiber output. The sweeping rate could be adjusted between 7 and 21.5 MHz by changing the geometry of the pump cavity. By controlling the ratio of the transverse mode amplitudes, we were able to tune the sweeping bandwidth, eventually covering both the 1300 nm and 1700 nm bioimaging transparency windows. When compared with previously demonstrated wavelength-swept sources, our concept offers much broader tunability and higher speed. Moreover,it does not require an additional intensity modulator.

关键词： Ultrabroadband wavelength-swept source

Microstructural Development of Ti-B Alloyed Layer for Hard Tissue Applications

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Journal of Materials Science & Technology 2013年第6期29卷 565-572页

作者： A.Miklaszewski M.U.Jurczyk M.Jurczyk Institute of Materials Science and Engineering Poznan University of TechnologyM.Sklodowska-Curie 5 Sq.60-965 PoznanPoland Mother's and Child's Health Division Poznan University of Medical SciencesPolna 3360-535 PoznanPoland

Microstructural development was analyzed due to the effect of different sizes of precursor powders during surface plasma alloying modification on titanium surface. Ti-B nano and micropowders with 10 wt% B were deposited onto microcrystalline titanium substrate by plasma alloying. As a result, modified surface layer composed of Ti matrix and TiB borides was obtained. The type of the powder precursor influenced recasting process, possible occurrence of porosity and finally the obtained properties and microstructure of the surface layer. Different morphologies and sizes of TiB phase from micro, submicro to even nano increased the hardness and wear resistance of the obtained surface layers. Discussed results referred to a strong TiB precipitation dispersion provided by a fine elements homogenization during mechanical alloying process. Additionally, results of in vitro test with normal human osteoblast cells revealed proper cellular adhesion to modified surfaces. Scanning electron microscopy observation revealed the influence of gas pore size on culturing osteoblast colony. The proposed surface alloying was an effective method of producing TiB phase dispersed in α-Ti matrix with high hardness, good corrosion resistance and good cytocompatibility. Results confirmed that different types of the precursor powders influenced the properties of the surface layer. TiB phase dispersed in α-Ti matrix layer can offer new structural and biofunctional properties for innovative products in hard tissue applications.

关键词： Titanium TiB phase Nano and micro precursors Microstructure Corrosion resistance Cytocompatibility

Machine learning-based decision tool for selecting patients with idiopathic acute pancreatitis for endosonography to exclude a biliary aetiology

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世界胃肠病学杂志:英文版 2023年第35期29卷 5138-5153页

作者： Simon Sirtl Michal Żorniak Eric Hohmann Georg Beyer Miriam Dibos Annika Wandel Veit Phillip Christoph Ammer-Herrmenau Albrecht Neesse Christian Schulz Jörg Schirra Julia Mayerle Ujjwal Mukund Mahajan Department of Medicine II LMU University HospitalMunich 81377Germany Department of Endoscopy Maria Sklodowska-Curie National Research Institute of OncologyGliwice 44-113Poland Department of Internal Medicine II School of MedicineUniversity Hospital Rechts der IsarTechnical University of MunichMunich 81675Germany Department of Gastroenterology Gastrointestinal Oncology and EndocrinologyUniversity Medical CenterGöttingen 37075Germany

BACKGROUND Biliary microlithiasis/sludge is detected in approximately 30%of patients with idiopathic acute pancreatitis(IAP).As recurrent biliary pancreatitis can be prevented,the underlying aetiology of IAP should be *** To develop a machine learning(ML)based decision tool for the use of endosonography(EUS)in pancreatitis patients to detect sludge and *** We retrospectively used routinely recorded clinical and laboratory parameters of 218 consecutive patients with confirmed AP admitted to our tertiary care hospital between 2015 and *** who did not receive EUS as part of the diagnostic work-up and whose pancreatitis episode could be adequately explained by other causes than biliary sludge and microlithiasis were *** trained supervised ML classifiers using H_(2)*** automatically selecting the best suitable predictor model to predict microlithiasis/*** predictor model was further validated in two independent retrospective cohorts from two tertiary care centers(117 patients).RESULTS Twenty-eight categorized patients’variables recorded at admission were identified to compute the predictor model with an accuracy of 0.84[95%confidence interval(CI):0.791-0.9185],positive predictive value of 0.84,and negative predictive value of 0.80 in the identification cohort(218 patients).In the validation cohort,the robustness of the prediction model was confirmed with an accuracy of 0.76(95%CI:0.673-0.8347),positive predictive value of 0.76,and negative predictive value of 0.78(117 patients).CONCLUSION We present a robust and validated ML-based predictor model consisting of routinely recorded parameters at admission that can predict biliary sludge and microlithiasis as the cause of AP.

关键词： Acute pancreatitis Idiopathic acute pancreatitis Biliary pancreatitis Microlithiasis Sludge Endosonography

The 4f-Hybridization Strength in Ce_(m)M_(n)In_(3m+2n) Heavy-Fermion Compounds Studied by Angle-Resolved Photoemission Spectroscopy

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Chinese Physics Letters 2021年第10期38卷 37-42页

作者： Jiao-Jiao Song Yang Luo Chen Zhang Qi-Yi Wu Tomasz Durakiewicz Yasmine Sassa Oscar Tjernberg Martin Mansson Magnus HBerntsen Yin-Zou Zhao Hao Liu Shuang-Xing Zhu Zi-Teng Liu Fan-Ying Wu Shu-Yu Liu Eric DBauer Ján Rusz Peter MOppeneer Ya-Hua Yuan Yu-Xia Duan Jian-Qiao Meng School of Physics and Electronics Central South UniversityChangsha 410083China Institute of Physics Maria Curie Sklodowska University20-031 LublinPoland Department of Physics and Astronomy Uppsala UniversityBox 516S-75120 UppsalaSweden Department of Physics Chalmers University of Technology41296 GoteborgSweden Department of Applied Physics KTH Royal Institute of TechnologyAlba Nova10691 StockholmSweden Condensed Matter and Magnet Science Group Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA

We systemically investigate the nature of Ce 4f electrons in structurally layered heavy-fermion compounds Ce_(m)M_(n)In_(3m+2n)(with M=Co,Rh,Ir,and Pt,m=1,2,n=0–2),at low temperature using on-resonance angle-resolved photoemission *** heavy quasiparticle bands f^(0),f^(1/7/2)and f^(1/5/2),are observed in all compounds,whereas their intensities and energy locations vary greatly with *** strong f0 states imply that the localized electron behavior dominates the Ce 4f *** Ce 4f electrons are partially hybridized with the conduction electrons,making them have the dual nature of localization and *** quantitative comparison reveals that the f^(1/5/2)–f^(0)intensity ratio is more suitable to reflect the 4f-state hybridization strength.

关键词： spectroscopy materials strength

Monitoring gully erosion in the European Union: A novel approach based on the Land Use/Cover Area frame survey (LUCAS)

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International Soil and Water Conservation Research 2022年第1期10卷 17-28页

作者： Pasquale Borrelli Jean Poesen Matthias Vanmaercke Cristiano Ballabio Javier Hervas Michael Maerker Simone Scarpa Panos Panagos Department of Earth and Environmental Sciences University of PaviaVia Ferrata127100PaviaItaly Department of Biological Environment Kangwon National UniversityChuncheon24341Republic of Korea Department of Earth and Environmental Sciences KU LeuvenBelgium Faculty of Earth Sciences and Spatial Management Maria-Curie Sklodowska UniversityLublinPoland Departement de Geographie Universite de LiegeLiegeBelgium European Commission Joint Research Centre(JRC)IspraItaly

The European Commission's Thematic Strategy for Soil Protection(COM(2012)46)identified soil erosion as an important threat to European Union's(EU)soil *** erosion is an important but hitherto poorly understood component of this *** we present the results of an unprecedented attempt to monitor the occurrence of gully erosion across the EU and *** integrate a soil erosion module into the 2018 LUCAS Topsoil Survey,which was conducted to monitor the soil health status across the EU and to support actions to prevent soil *** discuss and explore opportunities to further improve this *** 2018 LUCAS Topsoil Survey consisted of soil sampling(0-20 cm depth)and erosion observations conducted in ca.10%(n=24,759)of the 238,077 Land Use/Cover Area frame Survey(LUCAS)2018 in-field survey *** erosion channels were detected for ca.1%(211 sites)of the visited LUCAS Topsoil ***(false positives,2.5%)and omission errors(false negatives,5.6%)were found to be low and at a level that could not compromise the representativeness of the gully erosion ***,the findings indicate that the tested 2018 LUCAS Topsoil in-field gully erosion monitoring system is effective for detecting the incidence of gully *** morphogenesis of the mapped gullies suggests that the approach is an effective tool to map permanent gullies,whereas it appears less effective to detect short-lived forms like ephemeral *** patterns emerging from the LUCAS Topsoil field observations provide new insights on typical gully formation sites across the EU and *** can help to design further targeted research *** extension of this approach to all LUCAS sites of 2022 would significantly enhance our understanding of the geographical distribution of gully erosion processes across the *** every three years,LUCAS soil erosion surveys would contribute to assess the state of gully erosion in the EU over *** will also enable m

关键词： Soil erosion Soil Concentrated flow erosion Google earth Earth observations

Why Do the Main Sequence Stars Have Similar Chemical Composition?

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International Journal of Astronomy and Astrophysics 2012年第1期2卷 37-38页

作者： Stanislaw Halas Tomasz Durakiewicz Institute of Physics Maria Curie-Sklodowska University Lublin Poland Los Alamos National Laboratory MPA-CMMS Group Los Alamos USA

In this short note we have reconsidered the Jeans criterion for gravitational contraction of a gas nebula at different temperatures, from the present-day background radiation temperature (2.8 K) to those which existed at the early stage of the Universe. We demonstrate that the initial mass of quasars cannot be of the order of single galaxy masses, but rather 106 solar mass only. If they have larger masses, it must be the result of subsequent accretion process. Nevertheless quasars, formed prior to the stars, were the immediate source of the elements heavier than helium.

关键词： Stars Quasars Background Radiation Jeans Criterion Gravitational Contraction Nebulae