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同心连续油管用于水平井清砂

石油石化节能 1999年第8期 15-17页

作者： k.falk B．Fraser 赵小充长庆石油勘探局钻采院信息室

关键词：水平井连续油管射流泵除砂清砂

Phase imaging of irradiated foils at the OMEGA EP facility using phase-stepping X-ray Talbot–Lau deflectometry

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High Power Laser Science and Engineering 2023年第4期11卷 45-54页

作者： G.Pérez-Callejo V.Bouffetier L.Ceurvorst T.Goudal S.R.klein D.Svyatskiy M.Holec P.Perez-Martin k.falk A.Casner T.E.Weber G.kagan M.P.Valdivia Departamento de Física Teórica Atómica yÓptica Universidad de ValladolidValladolidSpain Universitéde Bordeaux-CNRS-CEA Centre Lasers Intenses et Applications(CELIA)UMR 5107TalenceFrance European XFEL GmbH SchenefeldGermany Laboratory for Laser Energetics RochesterNew YorkUSA CEA-DAM DIFArpajonFrance University of Michigan Ann ArborMichiganUSA Los Alamos National Laboratory Los AlamosNew MexicoUSA Lawrence Livermore National Laboratory LivermoreCaliforniaUSA Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany Institute of Physics of the ASCR PragueCzech Republic CEA-CESTA CS 60001Le Barp CedexFrance Blackett Laboratory Imperial College LondonLondonUK Department of Astrophysics and Astronomy The Johns Hopkins UniversityBaltimoreMarylandUSA Center for Energy Research University of California San DiegoSan DiegoCaliforniaUSA

Diagnosing the evolution of laser-generated high energy density(HED)systems is fundamental to develop a correct understanding of the behavior of matter under extreme ***–Lau interferometry constitutes a promising tool,since it permits simultaneous single-shot X-ray radiography and phase-contrast imaging of dense *** present the results of an experiment at OMEGA EP that aims to probe the ablation front of a laser-irradiated foil using a Talbot–Lau X-ray interferometer.A polystyrene(CH)foil was irradiated by a laser of 133 J,1 ns and probed with 8 keV laser-produced backlighter radiation from Cu foils driven by a short-pulse laser(153 J,11 ps).The ablation front interferograms were processed in combination with a set of reference images obtained ex situ using *** managed to obtain attenuation and phase-shift images of a laser-irradiated foil for electron densities above 1022 cm−*** results showcase the capabilities of Talbot–Lau X-ray diagnostic methods to diagnose HED laser-generated plasmas through high-resolution imaging.

关键词： deflectometry OMEGA EP phase-contrast imaging Talbot-Lau X-ray interferometry

P3: An installation for high-energy density plasma physics and ultra-high intensity laserematter interaction at ELI-Beamlines

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Matter and Radiation at Extremes 2017年第4期2卷 149-176页

作者： S.Weber S.Bechet S.Borneis L.Brabec M.Bucka E.Chacon-Golcher M.Ciappina M.DeMarco A.Fajstavr k.falk E.-R.Garcia J.Grosz Y.-J.Gu J.-C.Hernandez M.Holec P.Janecka M.Jantac M.Jirka H.kadlecova D.khikhlukha O.klimo G.korn D.kramer D.kumar T.Lastovicka P.Lutoslawski L.Morejon V.Olsovcova M.Rajdl O.Renner B.Rus S.Singh M.Smid M.Sokol R.Versaci R.Vrana M.Vranic J.Vyskocil A.Wolf Q.Yu ELI-Beamlines Institute of PhysicsAcademy of Sciences of the Czech Republic18221 PragueCzech Republic

ELI-Beamlines(ELI-BL),one of the three pillars of the Extreme Light Infrastructure endeavour,will be in a unique position to perform research in high-energy-density-physics(HEDP),plasma physics and ultra-high intensity(UHI)ð>10^(22) W=cm^(2)) lasereplasma *** the need for HED laboratory physics was identified and the P3(plasma physics platform)installation under construction in ELI-BL will be an *** ELI-BL 10 PW laser makes possible fundamental research topics from high-field physics to new extreme states of matter such as radiation-dominated ones,high-pressure quantum ones,warm dense matter(WDM)and ultra-relativistic *** is of fundamental importance for research in the field of laboratory astrophysics and inertial confinement fusion(ICF).Reaching such extreme states of matter now and in the future will depend on the use of plasma optics for amplifying and focusing laser *** article will present the relevant technological infrastructure being built in ELI-BL for HEDP and UHI,and gives a brief overview of some research under way in the field of UHI,laboratory astrophysics,ICF,WDM,and plasma optics.

关键词： High-energy-density-physics Ultra-high-intensity Warm dense matter Laboratory astrophysics High repetition rate lasers Plasma optics Inertial confinement fusion Lasereplasma interaction Relativistic plasmas

Wireless data transmission using visual codes

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Photonics Research 2014年第5期2卷 150-160页

作者： Thilo Fath falk Schubert Harald Haas Institute for Digital Communications University of EdinburghEH93JL EdinburghUK Innovation Works Germany EADS Deutschland GmbH81663 MunichGermany

In this paper,a new approach for wireless data transmission within an aircraft cabin is *** proposed application enables the transmission of data to a passenger’s user *** wireless in-flight applications are subject to strict frequency and electromagnetic compatibility(EMC)regulations,the data is transferred by optical wireless transmission,specifically by two-dimensional visual *** this end,black-and-white or colored visual code sequences are displayed on the in-flight entertainment *** visual codes are captured by the built-in camera of the passenger’s mobile device and are decoded to reconstruct the transmitted *** order to compensate for frame losses caused by effects like occlusion and motion blur,a temporal forward error correction coding scheme is *** experiments within an Airbus A330 cabin mock-up demonstrate the functionality of the implemented system under realistic conditions such as ambient illumination and geometric *** user devices are used for evaluation;specifically,a low-cost and a high-end smartphone are employed as *** evaluations show that the proposed transmission system achieves data rates of up to 120 kbit/s per individual passenger seat with these user *** the user device has no physical connection to the sensitive on-board system,the proposed transmission system provides an intrinsic safety feature.

关键词： visual illumination correction

Constructing Restricted Patterson Measures for Geometrically Infinite kleinian Groups

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Acta Mathematica Sinica,English Series 2006年第2期22卷 431-446页

作者： kurt falk Bernd O. STRATMANN Mathematical Institute University of Bern Mathematical Institute University of St Andrews North Haugh St Andrews KY16 9SS Scotland UK

In this paper, we study exhaustions, referred to as p-restrictions, of arbitrary nonelementary kleinian groups with at most finitely many bounded parabolic elements. Special emphasis is put on the geometrically infinite case, where we obtain that the limit set of each of these kleinian groups contains an infinite family of closed subsets, referred to as p-restricted limit sets, such that there is a Poincaré series and hence an exponent of convergence δp, canonically associated with every element in this family. Generalizing concepts which are well known in the geometrically finite case, we then introduce the notion of p-restricted Patterson measure, and show that these measures are non-atomic, δp-harmonic, δp-subconformal on special sets and δp-conformal on very special sets. Furthermore, we obtain the results that each p-restriction of our kleinian group is of δp-divergence type and that the Hausdorff dimension of the p-restricted limit set is equal to δp.

关键词： kleinian group Patterson measure Hausdorff dimension

Removal of perfluorinated surfactants from wastewater by adsorption and ion exchange--Influence of material properties,sorption mechanism and modeling

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Journal of Environmental Sciences 2017年第4期29卷 160-170页

作者： falk Schuricht Ekaterina S.Borovinskaya Wladimir Reschetilowski Institute of Industrial Chemistry Dresden University of Technology

Perfluorooctane sulfonate（PFOS） has attracted increasing concern in recent years due to its world-wide distribution, persistence, bioaccumulation and potential toxicity. The influence of sorbent properties on the adsorptive elimination of PFOS from wastewater by activated carbons, polymer adsorbents and anion exchange resins was investigated with regard to their isotherms and kinetics. The batch and column tests were combined with physicochemical characterization methods, e.g., N2 physisorption, mercury porosimetry, infrared spectroscopy, differential scanning calorimetry, titrations, as well as modeling. Sorption kinetics was successfully modelled applying the linear driving force（LDF） approach for surface diffusion after introducing a load dependency of the mass transfer coefficient β*** big difference in the initial mass transfer coefficient βs,0, when non-functionalized adsorbents and ion-exchange resins are compared, suggests that the presence of functional groups impedes the intraparticle mass transport. The more functional groups a resin possesses and the longer the alkyl moieties are the bigger is the decrease in sorption *** the selectivity for PFOS sorption is increasing when the character of the functional groups becomes more hydrophobic. Accordingly, ion exchange and hydrophobic interaction were found to be involved in the sorption processes on resins, while PFOS is only physisorptively bound to activated carbons and polymer adsorbents. In agreement with the different adsorption mechanisms, resins possess higher total sorption capacities than adsorbents. Hence, the latter ones are rendered more effective in PFOS elimination at concentrations in the low μg/L range, due to a less pronounced convex curvature of the sorption isotherm in this concentration range.

关键词： PFOS Activated carbon Anion exchange resin Sorption kinetics modeling Sorption isotherm Selectivity of sorption

Quantifying land degradation in the Zoige Basin,NE Tibetan Plateau using satellite remote sensing data

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Journal of Mountain Science 2017年第1期14卷 77-93页

作者： YU kai-feng Frank LEHMkUHL Dimitri falk Department of Geography RWTH Aachen University Templergraben 55 52056 Aachen Germany

Considerable efforts have been dedicated to desertification research in the arid and semi-arid drylands of central Asia. However,there are few quantitative studies in conjunction with proper qualitative evaluation concerning land degradation and aeolian activity in the alpine realm. In this study,spectral information from two Landsat-5 TM scenes(04.08.1994 and 28.07.2009,respectively) was combined with reference information obtained in the field to run supervised classifications of eight landscape types for both time steps. Subsequently,the temporal and spatial patterns of the alpine wetlands/grasslands evolutions in the Zoige Basin were quantified and assessed based on these two classification maps. The most conspicuous change is the sharp increase of ~627 km^2 degraded meadow. Concerning other land-covers,shallow wetland increases ~107 km^2 and aeolian sediments(mobile dunes and sand sheets) have an increase of ~30 km^2. Considering the deterioration,an obvious decrease of ~440 km^2 degraded wetland can be observed. Likewise,decrease of deep wetland(~78 km^2),humid meadow(~80 km^2) and undisturbed meadow(~88 km^2) were determined. These entire evolution matrixes undoubtedly hint a deteriorating tendency of the Zoige Basin ecosystem,which is characterized by significantly declined proportion of intact wetlands,meadow,rangeland and a considerable increase ofdegraded meadow and larger areas of mobile dunes. In particular,not only temporal alteration of the landcover categories,the spatial and topographical characteristics of the land degradation also deserves more attention. In the alpine rangelands,the higher terraces of the river channels along with their slopes are more liable to the degradation and desertification. This tendency has significantly impeded the nomadic and agriculture activities. The set of anthropozoogenic factors encompassing enclosures,overgrazing and trampling,rodent damaging and exceedingly ditching in the wetlands are assumed to be the main co

关键词： Alpine ecosystem Wetlands Degradation Desertification Zoige Basin Driving mechanisms

Glass transition temperature prediction of disordered molecular solids

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npj Computational Materials 2021年第1期7卷 1633-1639页

作者： kun-Han Lin Leanne Paterson falk May Denis Andrienko Max Planck Institute for Polymer Research Ackermannweg 1055128 MainzGermany Merck kGaA 64293 DarmstadtGermany

Glass transition temperature,Tg,is the key quantity for assessing morphological stability and molecular ordering of films of organic semiconductors.A reliable prediction of Tg from the chemical structure is,however,challenging,as it is sensitive to both molecular interactions and analysis of the heating or cooling *** combining a fitting protocol with an automated workflow for forcefield parameterization,we predict Tg with a mean absolute error of~20℃for a set of organic compounds with Tg in the 50–230℃*** study establishes a reliable and automated prescreening procedure for the design of amorphous organic semiconductors,essential for the optimization and development of organic light-emitting diodes.

关键词： automated prediction transition

Obtaining the best possible predictions of habitat selection for wintering Great Bustards in Cangzhou, Hebei Province with rapid machine learning analysis

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Chinese Science Bulletin 2014年第32期59卷 4323-4331页

作者： Chunrong Mi falk Huettmann Yumin Guo College of Nature Conservation Beijing Forestry University EWHALE Laboratory Department of Biology and WildlifeInstitute of Arctic Biology University of Alaska Fairbanks Biology Fairbanks AK 99775 USA

Great Bustards(Otis tarda dybowskii)are one of the world’s heaviest flying birds,occupying grassland habitats in Eastern *** study is located at the most eastern Chinese wintering site in Cangzhou,Hebei Province,where approximately 100 individuals are concentrated in a small area(17.53 km2).Solid information is still lacking about the wintering areas for this subspecies in its eastern range and specifically for *** study area consists of intensely used farmland in proximity to humans and is lacking conservation areas and wild,open ***,we present our results from two years of field data collection on habitat *** choose a machine learning model approach based on a rapid assessment methodology for the winter habitat of the Great *** is based on a spatial analysis of the best available environmental data,which were collected relatively *** relatively new methods in ecology are based on an ensemble of decision trees and include algorithms such as TreeNet,Random Forest and CART used in *** this study,we collected bustard droppings(presence only)from 48 locations between December 2011 and January 2012 and used the sites as training *** from 23 locations were collected in November 2012,and those sites were used as test *** used eight environmental variables as predictor layers for the response variable of bustard presence/*** employed a Geographic Information System(ArcGIS 10.1and Geospatial Modelling Environment)and Google *** with the other three models,we found that predictions from Random Forest obtained a significant difference between presence and *** to this model,the three most important factors for wintering Great Bustards are distance to residential area,distance to water pools,and farmland *** model shows that wintering Great Bustards prefer locations that are over 400 m away from residential areas,within 900 m of water pools and on areas of farmland smal

关键词：河北省沧州市栖息地选择机器学习越冬地大鸨预测地理信息系统野外数据采集