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Fluid Structure Interaction Problems:the Necessity of a Well Posed,Stable and Accurate Formulation

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Communications in Computational Physics 2010年第10期8卷 1111-1138页

作者： jan Nordstrom Sofia Eriksson School of Mechanical Industrial and Aeronautical EngineeringUniversity of the WitwatersrandJohannesburgWITS 2050South Africa Department of Aeronautics and Systems Integration FOIThe Swedish Defense Research AgencySE-16490 StockholmSweden Department of Information Technology Division of Scientific ComputingUppsala UniversitySE-75105 UppsalaSweden

We investigate problems of fluid structure interaction type and aim for a formulation that leads to a well posed problem and a stable numerical *** first objective is to investigate if the generally accepted formulations of the fluid structure interaction problem are the only possible *** second objective is to derive a stable numerical *** accomplish that we will use a weak coupling procedure and employ summation-by-parts operators and penalty *** compare the weak coupling with other common *** also study the effect of high order accurate *** multiple dimensions this is a formidable task and we start by investigating the simplest possible model problem *** a flow model we use the linearized Euler equations in one dimension and as the structure model we consider a spring.

关键词： Fluid structure interaction well posed finite difference high accuracy stability

Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

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Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen Erik jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

Language, Conceptualization and TAM Marking： A Cognitive-functional Perspective

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外国语 2009年第1期32卷 2-43页

作者： jan Nuyts University of Antwerp Belgium

At the level of empirical phenomena,this paper deals with the system of 'Tense Aspect Modality' marking or of 'qualificational categories' in *** is this system organized? What are the principles behind it? The major focus is on the modal *** the theoretical level,this paper addresses issues pertaining to the organization and functioning of the cognitive systems involved in language use,with special focus on the differences and correspondences between two major theoretical strands in present day linguistics,viz.'functional linguistics' and 'cognitive linguistics'.

关键词：语言概念化认知功能英语语法

Mechanical circulatory support in cardiogenic shock and post-myocardial infarction mechanical complications

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Journal of Geriatric Cardiology 2022年第2期19卷 130-136页

作者： Daniel Rob jan Bělohlávek nd Department of Medicine-Department of Cardiovascular Medicine First Faculty of MedicineCharles University and General University HospitalPragueCzech Republic

Despite advanced therapies,the mortality of patients with myocardial infarction(MI)complicated by cardiogenic shock(CS)remains around 50%.Mechanical complications of MI are rare nowadays but associated with high mortality in patients who present with *** treatment strategies and mechanical circulatory support(MCS)devices have been increasingly used to improve the grim prognosis of refractory *** article discusses current evidence regarding the use of MCS in MI complicated by CS,ventricular septal rupture,free wall rupture and acute mitral *** selection should be tailored according to the cause and severity of *** MCS initiation and multidisciplinary team cooperation is mandatory for good *** associated bleeding remains a major complication and an obstacle to better *** prospective randomized trials will improve current knowledge regarding MCS indications,timing,and patient selection in the coming years.

关键词： mortality infarction rupture

IGC 2004——Urbino International Workshop to discuss some new concepts in global tectonics

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Episodes 2005年第1期28卷 55-57页

作者： jan Passava GEOCHIM Courses Czech Geological Survey

In the context of the 32^nd International Geological Congress, the University of Urbino which is about to celebrate its 500^th anniversary hosted the post-Congress Workshop PWO-09 from 29^th to 31^st August 2004 dedicated to “New Concepts in Global Tectonics：Emphasis on Some Fundamental Questions in Geology”, convened and organized by Forese Carlo Wezel.

关键词： 2004年世界地质学大会地质构造学术成果成岩作用

Ability for Self-Pelletization of Iron Ores and Magnetite Concentrates

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Journal of Iron and Steel Research International 2011年第6期18卷 1-7页

作者： Francik Przemysaw jan Mróz Czestochowa University of Technology Czestochowa 42-200Poland

A procedure for evaluating the susceptibility of raw materials for the process of sintering of iron ore mixes is presented. The procedure relies on the evaluation of the amount and quality of the finest grain fraction. The method is based on determination of particular grain fractions. For the grain less than 0.15 mm, the determination of the a- mount is performed using an IPS （Infrared Particles Sizer） grain size analyzer and for the grain larger than 0.15 ram, the fraction is determined using the （wet and dry） screening methods. This allows for quantity assessment of the quality of material in terms of its susceptibility to self-pelletizing by calculating Total Ability for SelPPelletizing （TASP） index fT. The presented method, in combination with the grain size and chemical analyses, can serve for evaluation of suitability of raw material and mixes for the sintering process. Furthermore, the TASP index for 10 types of iron ores and concentrates was determined. The usability of the TASP index was verified by determination of its impact on yield of sintering process both in laboratory and in industry scale.

关键词： iron ore concentrate grain composition pelletization process sintering process productivity

高温高压下Saraline基超轻完井液黏度预测模型优选

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石油勘探与开发 2016年第5期43卷 793-798页

作者： AMIR Zulhelmi jan Badrul Mohamed WAHAB Ahmad Khairi Abdul KHaliL Munawar ali Brahim Si CHONG Wen Tong University of Malaya Center for Sustainable Infrastructure Development(CSID) University of Indonesia

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度... 详细信息

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度降幅较小,且黏度对压力变化不敏感。将实验测量数据与4个常用黏度-温度-压力模型进行拟合,发现利用改进型Mehrotra-Svreck模型和Ghaderi模型预测的黏度值与测量值吻合度较高,能够描述高温高压下Saraline基超轻完井液的黏度特性。与Sarapar基超轻完井液对比后发现,温度对Saraline基超轻完井液黏度的影响更小,压力对Saraline基超轻完井液黏度的影响可以忽略不计,改进型Mehrotra-Svreck模型和Ghaderi模型在各种温度和压力条件下对Saraline基超轻完井液的黏度预测精度优于对Sarapar基超轻完井液的黏度预测。

关键词：高温高压黏度预测超轻完井液 Saraline合成油欠平衡射孔

Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： Katerina Kusova Ivan Pelant jan Valenta Institute of Physics of the ASCR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNCs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNCs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNCs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

Electrodynamics of Abrikosov vortices： the field theoretical formulation

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Frontiers of physics 2011年第4期6卷 357-369页

作者： Aron J. Beekman jan Zaanen Instituut-Lorentz for Theoretical Physics Universiteit Leiden P. O. Box 9506 2300 RA Leiden The Netherlands

Electrodynamic phenomena related to vortices in superconductors have been studied since their prediction by Abrikosov, and seem to hold no fundamental mysteries. However, most of the effects are treated separately, with no guiding principles. We demonstrate that the relativistic vortex worldsheet in spacetime is the object that naturally conveys all electric and magnetic information, for which we obtain simple and concise equations. Breaking Lorentz invariance leads to down-to-earth Abrikosov vortices, and special limits of these equations include for instance dynamic Meissner screening and the AC Josephson relation. On a deeper level, we explore the electrodynamics of two-form sources in the absence of electric monopoles, in which the electromagnetic field strength itself acquires the characteristics of a gauge field. This novel framework leaves room for unexpected surprises .

关键词： Abrikosov vortex, electromagnetism, Maxwell equations, differential geometry multivalued fields