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Volumetric lattice Boltzmann method for pore-scale mass diffusionadvection process in geopolymer porous structures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2126-2136页

作者： Xiaoyu Zhang Zirui Mao Floyd W.Hilty Yulan Li Agnes Grandjean Robert Montgomery hans-Conrad zur Loye Huidan Yu Shenyang Hu Purdue university IndianapolisIN46202USA Pacific Northwest National Laboratory RichlandWA99352USA CEA DESISECDMRCUniv.MontpellierMarcouleFrance Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC29208USA

Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste *** improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material *** this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous *** structures are created using the phase field method(PFM)to precisely control pore *** our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population *** address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPu)*** of the developed model involves examining the flow and diffusion fields in porous ***,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,***,all three parameters exert an influence on the diffusion-advection *** background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,***,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore *** comprehensive parametric study provides valuable insights into the kinetics of isotope

关键词： Volumetric lattice Boltzmann method(VLBM) Phase field method(PFM) Pore-scale diffusion-advection Nuclear waste treatment Porous media flow Graphics processing unit(GPu) parallelization

A Note on Moments of Dividends

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Acta Mathematicae Applicatae Sinica 2011年第3期27卷 353-354页

作者： hansjrg Albrecher hans.u.Gerber Professor of Actuarial Science Faculty of Business and EconomicsUniversity of LausanneCH-1015 LausanneSwitzerland and Faculty Member of the Swiss Finance Institute Distinguished Visiting Professor at the university of Hong Kong Honorary Professor of Actuarial Science Faculty of Business and EconomicsUniversity of LausanneCH-1015 LausanneSwitzerland

We reconsider a formula for arbitrary moments of expected discounted dividend payments in a spectrally negative Lévy risk model that was obtained in Renaud and Zhou （2007, [4]） and in Kyprianou and Palmowski （2007... 详细信息

关键词： dividends barrier strategies stationary Markov process scale function

A Population Balance Model for Disperse Systems:Particle Size Distribution in Suspension Polymerization

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Chinese Journal of Chemical Engineering 1999年第4期7卷 332-344页

作者：陈中 Werner Pauer H.-u.Moritz Jan Prss hans-Joachim Warnecke Chemical Engineering University of PaderbornPaderborn 33098Germany

On the basis of population balance a mathematical model is developed to describe the formation of polymer particle in styrene suspension polymerization. The characteristics of coalescence and breakage of droplets and the gel effect are analyzed in particular. Parameters of the models are estimated by experimental data on reaction conversion and particle size distribution. The results show that the model is suitable for predicting polymerization processes.

关键词： population balance model styrene suspension polymerization particle size distribution

辽东湾浅海湿地表层沉积物重金属污染变化及其生态风险：基于2005和2013年度调查数据对比分析

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中国地质 2024年

作者：陈洋洋叶思源丁喜桂谢柳娟周攀裴理鑫袁红明高宗军 Edward A.Laws hans Brix 山东科技大学地球科学与工程学院青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室路易斯安那州立大学海岸和环境学院环境科学系中国地质调查局滨海湿地生物地质重点实验室自然资源部北方滨海盐沼湿地生态地质野外科学观测研究站青岛海洋地质研究所奥胡斯大学生物科学系

【研究目的】查明重金属分布特征及来源，为辽东湾重金属污染历史变化提供新的量化数据和深刻认识，为政府根据经济发展指标变化示踪近海污染演变趋势提供历史案例。【研究方法】通过对2005年及2013年的辽东湾浅海湿地表层沉积物样品中... 详细信息

【研究目的】查明重金属分布特征及来源，为辽东湾重金属污染历史变化提供新的量化数据和深刻认识，为政府根据经济发展指标变化示踪近海污染演变趋势提供历史案例。【研究方法】通过对2005年及2013年的辽东湾浅海湿地表层沉积物样品中7种重金属(As、Cd、Pb、Zn、Cu、Cr、Hg)、有机碳 (Corg) 和粒度进行分析，研究了辽东湾表层沉积物中重金属及Corg的空间分布特征、污染来源和生态风险贡献。【研究结果】结果表明，2005年和2013年各元素的重金属空间分布特征一致，都在小凌河西南端显著富集，且受粒度控制。重金属浓度空间分布整体呈现南部>中部>北部和西部>东部>中部。2005年(2013年)重金属来源于工业、农业和母岩分别占40.68%(29.03%)、36.69%(48.03%)、22.63%(22.94%)。相较于2005年，2013年随着沿岸城市产业结构调整，重金属来源发生显著变化，且地理探测器分析揭示农业生产对重金属总体生态风险 (RI) 增加贡献最高。通过对地质累积指数 (Igeo) 和正交矩阵因子分解法 (PMF) 分析研究发现，相较于2005年，2013年表层沉积物中Cr、Cu、Pb、Zn元素污染轻微加重，As和Hg元素明显加重，相反Cd元素污染明显减轻。暗示工业排污控制对减少Cd污染起到重要作用，而其他重金属污染主要源于农业生产活动，亦或海上运输对Pb污染也有一定的贡献。【结论】虽然辽东湾附近城市经济增长2-3倍，但是政府注重控制工业废水的处理与排放，使重金属污染增长的较为平缓，但重金属Hg、Cu、Pb和Zn元素的污染仍不能忽略，特别是在粒度较细的泥质沉积物区，重金属As和Hg的生态风险程度较严重。

关键词：重金属污染来源污染变化沉积物粒度 PMF模型地理探测器生态风险评价辽东湾浅海湿地环境地质调查工程

Imaging for deep brain stimulation:The zona incerta at 7 Tesla

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World Journal of Radiology 2013年第1期5卷 5-16页

作者： hans.u kerl Lars Gerigk Marc A Brockmann Sonia Huck Mansour AlZghloul Christoph Groden Thomas Hauser Armin M Nagel Ingo S Nlte Department of Neuroradiology University Medical Center MannheimUniversity of Heidelberg68167 MannheimGermany Division of Radiology German Cancer Research Center69120 HeidelbergGermany Department of Medical Physics and Radiology German Cancer Research Center69120 HeidelbergGermany

AIM:To evaluate different promising magnetic resonance imaging(MRI) methods at 7.0 Tesla(T) for the pre-stereotactic visualization of the zona incerta(ZI).METHODS:Two neuroradiologists qualitatively and quantitatively examined T2-turbo spin-echo(T2-TSE),T1-weighted gradient-echo,as well as FLASH2D-T2Star and susceptibility-weighted imaging(SWI) for the visualization of the ZI at 7.0 T *** and image quality for the ZI were independently examined using a 6-scale grading ***-rater reliability using Cohen's kappa coefficient(κ) were ***-tonoise ratios(CNR),and signal-to-noise ratios(SNR) for the ZI were calculated for all *** in delineation,SNR,and CNR between the sequences were statistically assessed using a paired *** the anatomic validation the coronal FLASH2D-T2Star images were co-registered with a stereotactic atlas(Schaltenbrand-Wahren).RESuLTS:The rostral part of the ZI(rZI) could easily be identified and was best and reliably visualized in the coronal FLASH2D-T2Star *** caudal part was not definable in any of the *** major artifacts in the rZI were observed in any of the ***2D-T2Star and SWI imaging offered significant higher CNR values for the rZI compared to T2-TSE images(P > 0.05).The co-registration of the coronal FLASH2D-T2Star images with the stereotactic atlas schema(Schaltenbrand-Wahren) confirmed the correct localization of the ZI in all ***:FLASH2D-T2Star imaging(particularly coronal view) provides the reliable and currently optimal visualization of the rZI at 7.0 *** results can facilitate a better and more precise targeting of the caudal part of the ZI than ever before.

关键词： Deep brain stimulation Essential tremor Magnetic resonance imaging Parkinson’s disease Zona incerta 7 Tesla

Severe chronic diarrhea and weight loss in cholesteryl ester storage disease: A case report

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World Journal of Gastroenterology 2005年第15期11卷 2364-2366页

作者： uta Drebber Matthias Andersen hans.u Kasper Peter Lohse Manfred Stolte hans P Dienes Institute of Pathology Department of Internal Medicine Department of Clinical Chemistry-Grosshadern

AIM: An inherited deficiency of human lysosomal acid lipase (LAL)results in the rare conditions of Wolman disease and cholesteryl ester storage disease (CESD). We want to present the rare case of CESD in an ***: We report about an adult female patient with severe chronic diarrhea and weight loss as a consequence of CESD. Clinical examination revealed signs of malabsorption and slightly elevated liver ***: Histopathologic changes in the liver tissue and DNA sequence analysis confirmed the diagnosis of CESD due to homozygosity for the most common CESD mutation,a G934A splice site defect encoded by exon 8 of the lysosomal acid lipase (LIPA) ***: It is the first case in the literature with diarrhea as a putative symptom of CESD in adult patients.

关键词： CESD Acid esterase Hydrolase Liver biopsy Pathology Diarrhea

Metamorphic Evolution of Chloritoid-Bearing Micaschist from the Variscan Elstergebirge: Evidences for Stacking of High-Pressure Rocks in the Saxothuringian Zone of Central Europe

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Journal of Earth Science 2020年第3期31卷 425-446页

作者： Gelareh Rahimi hans-Joachim Massonne Fakultat Chemie Universitat Stuttgart70569 StuttgartGermany School of Earth Sciences China University of GeosciencesWuhan 430074China

A chloritoid-garnet-bearing micaschist from the southern part of the Elstergebirge was studied to better understand the Variscan orogenic evolution in the Saxothuringian zone of the northwestern Bohemian *** on the textural relations and compositions of minerals,especially of zoned garnet and potassic white mica,a P-T path was reconstructed using contoured P-T *** u-Th-Pb dating of monazite in the micaschist was undertaken with the electron *** micaschist experienced P-T conditions along a clockwise path between 16 kbar at 510℃and 5 kbar at 555℃followed by isobaric heating to about 600℃.Monazite ages range between 315 and 480 Ma with the most prominent maxima and side maxima at 346.0±1.1(2σ),357.3±2.3,and 368.3±1.7 *** older than 380 Ma were related to detrital monazite pointing to a Devonian sedimentary *** ages around 325 Ma were assigned to the isobaric heating by nearby post-tectonic *** high-pressure event,being the result of the collision of Laurussia and Gondwana after closure of the Rheic Ocean,occurred in the Late *** exhumation to 15-20 km(5 kbar)ended probably in the Early *** high-pressure micaschists from the Fichtelgebirge to the Erzgebirge crystalline complexes are suggested to represent a single nappe within a metamorphic nappe *** nappe is composed of metasedimentary slices,which experienced different peak pressures rather than representing a coherent crustal section.

关键词： Saxothuringian micaschist chloritoid garnet monazite dating Variscan P-T path

Morrey smoothness spaces:A new approach

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Science China Mathematics 2023年第6期66卷 1301-1358页

作者： Dorothee D.Haroske hans Triebel Institute of Mathematics Faculty of Mathematics and Computer ScienceFriedrich Schiller University JenaJena 07743Germany

In the recent years,the so-called Morrey smoothness spaces attracted a lot of *** can(also)be understood as generalisations of the classical spaces A_(p,q)^(s)(R^(n))with A∈{B,F}in R^(n),where the parameters satisfy s∈R(smoothness),0ummability).In the case of Morrey smoothness spaces,additional parameters are *** our opinion,among the various approaches at least two scales enjoy special attention,also in view of applications:the scales A_(p,q)^(s)(R^(n))with A∈{N,E}and u≥p,and A_(p,q)^(s),τ(R^(n))with A∈{B,F}andτ≥*** reorganise these two prominent types of Morrey smoothness spaces by adding to(s,p,q)the so-called slope parameter e,preferably(but not exclusively)with-n eut that|e|replaces n,and min(|e|,1)replaces 1 in slopes of(broken)lines in the(1/p,s)-diagram characterising distinguished properties of the spaces A_(p,q)^(s)(R^(n))and their Morrey *** attention will be paid to low-slope spaces with-1uite often independent of n∈*** aim is *** the one hand,we reformulate some assertions already available in the literature(many of which are quite recent).On the other hand,we establish on this basis new properties,a few of which become visible only in the context of the offered new approach,governed,now,by the four parameters(s,p,q,e).

关键词： Morrey space smoothness space of Morrey type Besov-Morrey space Triebel-Lizorkin-Morrey space Besov-type space Triebel-Lizorkin-type space

STRuCTuRE IMAGING OF SILICATES: SuPERSTRuCTuRE OF CALCIC PLAGIOCLASE AND DEFECTS IN GADOLINIuM SILICATE

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STRUCTURE IMAGING OF SILICATES: SUPERSTRUCTURE OF CALCIC PLA...