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Gastrointestinal dysfunction in liver cirrhosis

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World Journal of Gastroenterology 2014年第40期20卷 14686-14695页

作者： evangelos Kalaitzakis Department of Gastroenterology Sk?ne University Hospital University of Lund 22185 Lund Sweden

Patients with liver cirrhosis exhibit several features of gut dysfunction which may contribute to the development of cirrhosis complications as well as have an impact on nutritional status and health-related quality of *** symptoms are common in cirrhosis and their pathophysiology probably involves factors related to liver disease severity,psychological distress,and gut dysfunction(e.g.,increased gastric sensitivity to distension and delayed gut transit).They may lead to reduced food intake and,thus,may contribute to the nutritional status deterioration in cirrhotic *** tense ascites appears to have a negative impact on meal-induced accommodation of the stomach,published data on gastric accommodation in cirrhotics without significant ascites are not *** emptying and small bowel transit have generally been shown to be *** may be related to disturbances in postprandial glucose,insulin,and ghrelin levels,which,in turn,appear to be associated to insulin resistance,a common finding in ***,small bowel manometry disturbances and delayed gut transit may be associated with the development of small bowel bacterial ***,several studies have reported intestinal barrier dysfunction in patients with cirrhosis(especially those with portal hypertension),which is related to bacterial translocation and permeation of intestinal bacterial products,e.g.,endo-toxin and bacterial DNA,thus potentially being involved in the pathogenesis of complications of liver cirrhosis.

关键词： Liver cirrhosis Gut motility Gastric accommodation Malnutrition Gastrointestinal symptoms Intestinal permeability

Turbulent structure in uniform inclined open channel flow over different rough porous beds

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International Journal of Sediment Research 2017年第1期32卷 45-52页

作者： evangelos Keramaris University of Thessaly Department of Civil EngineeringDivision of Hydraulic and Environmental Engineering

In this study the effects of the different rough porous beds in an open inclined channel are studied experimentally for impermeable and permeable porous *** the simulation of porous bed two different types of permeable bed with the same thickness(s’ = 3 cm) and the same porosity ε=0.70 are used:(a) porous filters and(b) gravel *** experiments were used for the calculation of turbulent velocity *** of velocity were taken for inclined channel for three different slopes(S=-0.002,S=-0.004 and S=-0.006) and for five different flow depths(h=5 cm,7 cm,9 cm,11 cm and 13 cm).The total discharge Q varies from 0.78 to 1.31 1/*** measurements were obtained using a two-dimensional(2D) Particle Image Velocimetry(PIV).The total discharge was estimated using a calibrated venture *** showed that the presence of rough porous bed in inclined open channels influence significantly the turbulent characteristics of the flow in comparison with impermeable open channels with the same slopes.

关键词： Particle image velocimetry Porous filters Gravel bed Channel slope Turbulent characteristics

A new framework for population balance modeling of spray fluidized bed agglomeration

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Particuology 2015年第2期13卷 141-154页

作者： Mubashir Hussain Jitendra Kumar evangelos Tsotsas Chair of Thermal Process Engineering Otto-von-Guericke University Magdeburg Department of Mathematics Indian Institute of Technology Kharagpur

Previous work （Hussain et al. （2013）. Chemical Engineering Science, 101, 35） has pointed out that the conventional, one-dimensional population balance equation for aggregation can be expanded to accurately reproduce the results of discrete simulations of spray fluidized bed agglomeration. However, some parameters had to be imported from the discrete simulation （Monte-Carlo）. The present paper shows how the expanded population balance can be run without importing parameters from the Monte-Carlo simulation. The expanded population balance still reproduces the results of Monte-Carlo simulations accurately, taking into account key micro-scale phenomena （sessile droplet drying, efficiency of collisions）, but with much lower computational cost. Required input parameters are just the drying time of sessile droplets （calculated in advance）, and the prefactor of an equation that correlates particle collision frequency with fluidized bed expansion. In this way, the expanded population balance is, apart from autonomous, also （nearly） predictive. Its performance is demonstrated by comparisons with both Monte-Carlo results and experimental data for various operating conditions （binder mass flow rate, gas temperature）. Despite formally being a one-dimensional expression, the expanded population balance captures additional properties, such as the number of wet particles and the number of droplets in the system, which are even difficult to measure in exoeriments.

关键词： Population balances Kinetics Aggregation Monte Carlo simulation Fluidized bed Modeling

Determination of particle exchange rates at over-flow weirs in horizontal fluidised beds by particle tracking velocimetry

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Particuology 2017年第3期15卷 1-9页

作者： Katja Meyer Andreas Buck evangelos Tsotsas Thermal Process Engineering Otto von Guericke University Magdeburg UniversitStsplatz 2 D-39106 Magdeburg Germany

Residence time distributions （RTDs） in horizontal fluidised beds have a huge effect on solid product properties and are infuenced by the internal design of the apparatus, e.g. the separation into different compartments by weirs. Weirs can be passed in or against the overall solid transport direction, with the back-flow resulting in axial dispersion, which is a measure of the spread of the RTD. Therefore, the ratio of exchange rates at weirs under different fluidisation conditions provides information on axial dispersion. In this work, a methodology based on particle tracking velocimetry is presented to obtain information on the exchange rates of particles at weirs in horizontal fluidised beds. The internal recirculation is studied for over-flow weirs with respect to different fluidisation conditions, providing a first step towards determining the effects of weirs and fluidisation conditions on axial dispersion and RTDs in horizontal fluidised beds.

关键词： Particle tracking velocimetry Horizontal fluidised bedAxial dispersion Granulation Drying

Ballistic design and testing of a composite armour reinforced by CNTs suitable for armoured vehicles

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Defence Technology（防务技术） 2024年第2期32卷 173-195页

作者： evangelos Ch.Tsirogiannis evangelos Daskalakis Mohamed H.Hassan Abdalla M.Omar Paulo Bartolo EODH SA Research and Development DepartmentLakkoma Chalkidikis63080Greece School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological University639798Singapore

This paper is investigating the use of composite armour reinforced by nanomaterials, for the protection of light armoured(LAV) and medium armoured military vehicles(MAV), and the interaction between the composite materials and high-performance ballistic projectiles. Four armour materials, consisted of front hybrid fibre reinforced polymer cover layer, ceramic strike-face, fibre reinforced polymer intermediate layer and the metal matrix composite reinforced backplate, were manufactured and assembled by adhesive technology. The proposed laminated protection system is suitable for armoured ground vehicles;however, it could be used as armour on ground, air and naval platforms. The design of the protection system, including material selection and thickness, was elaborated depending on the performance requirements of Level 4 + STANAG 4569 military standard(projectile 14.5 mm × 114 mm API B32) and especially on a design philosophy which is analysed with the specifications. The backplate of this new composite is a hybrid material of Metal Matrix Composite(MMC) reinforced with carbon nanotubes(CNTs), manufactured with the use of powder metallurgy technique. The composite backplate material was morphologically, mechanically and chemically analysed. Results show that all plates are presenting high mechanical properties and ballistic characteristics, compared to commonly used armour plates. Real military ballistic tests according to AEP-STANAG 4569 were carried out for the total composite armour systems. After the ballistic tests, AA2024-CNT3 showed the best protection results, compared with the other plates(AA2024-CNT1 and AA2024-CNT2), with the projectile being unable to fully penetrate the composite plate.

关键词： Passive armour protection Protective armour Ballistic performance Hybrid composites Vehicle protection

Study of water renewal and sedimentation of a square harbor encapsulated in a coastal front with seawalls due to wind-induced hydrodynamic circulation

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International Journal of Sediment Research 2021年第3期36卷 373-383页

作者： Yiannis Savvidis evangelos Keramaris InternationalHellenicUniversity DepartmentofEnvironmentalEngineering UniversityofThessaly DepartmentofCivilEngineering

In the current study in the middle of a coastal zone, a harbor basin in the form of a square area recessed to the front is considered. A breakwater of variable length and position offers protection from waves. The water renewal time and the self-purification capacity of the harbor under the influence of alongshore currents due to wind-induced water circulation of varying intensities were examined. Furthermore, the transport of particulate matter released from the upstream side of the coastal zone and the possible influence(via sedimentation) on the lateral basin was investigated. The current study was based on the use of a two-dimensional depth-averaged hydrodynamic model and a quasi-three-, dimensional transport model while the effect of partial closing of the harbor’s entrance was examined. The(1) adjustment and(2) validation of the reliability of the numerical model at a laboratory level were done using a recent research based on the use of a particle image velocimetry(PIV) measurements ensuring very good agreement between numerical and experimental results. The current study showed that the partial closing of the opening between the harbor basin and the extended coastal zone, with a breakwater of length equal to 1/3 of the opening, seems to be the most acceptable technical solution.

关键词： Coastal zone Numerical model PIV measurements Renewal time Self-purification capacity Matter transport

Parametric analysis of a solar-driven trigeneration system with an organic Rankine cycle and a vapor compression cycle

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Energy and Built Environment 2021年第3期2卷 278-289页

作者： evangelos Bellos Christos Tzivanidis Thermal Department School of Mechanical EngineeringNational Technical University of AthensZografouHeroon Polytechniou 915780 AthensGreece

The objective of this paper is the parametric analysis of a solar-fed trigeneration system ideal for the building sector that produces useful heat,electricity and *** examined unit is driven by 100 m^(2)of parabolic trough collectors which are combined with a sensible storage tank with thermal *** organic Rankine cycle is fed by solar useful heat production and it produces electricity while a part of its power drives a vapor compression cycle with *** is also produced by separate heat exchangers in the solar *** parametric analysis is conducted in steady-state conditions with a developed model in Engineering Equation *** examined parameters are the following:superheating degree in the turbine inlet,cooling production,heating production,solar beam irradiation intense,sun angle,pressure level in the turbine inlet and heat source temperature *** the nominal scenario of 10 kW cooling production at 5°C and 10 kW heating production at 60°C,the system produces 6.14 kW electricity,while the exergy and energy efficiencies are found 12.14%and 37.34%*** that the system operates 2500 h yearly,the simple payback period of the investment is calculated at 8.5 *** maximum examined values for both heating and cooling production are at 20 kW.

关键词： Solar concentrating power Trigeneration ORC Exergy Parabolic trough collector

Ultrathin coating of particles in fluidized bed using submicron droplet aerosol

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Particuology 2020年第6期18卷 23-29页

作者： Maksim Mezhericher Christian Rieck Nikolay Razorenov evangelos Tsotsas Mechanical and Aerospace Engineering Princeton UniversityPrincetonNJ 08544USA Thermal Process Engineering Otto-von-Guericke University39106 MagdeburgGermany Mechanical Engineering Shamoon College of EngineeringBeer Sheva84100Israel

In this work,we demonstrate that particles can be coated in a fluidized bed w让h coating solution provided by a novel aerosol *** droplets are smaller than 1 pim in volume-based diameter,hence they are very much smaller than droplets in conventional spray fluidized bed processes(around 40μm).A proof-of-principle experiment with 30%aqueous coating solution of sodium benzoate and γ-Al2O3 core particles in 150 mm fluidized bed fed with droplet aerosol supplied from the chamber side is *** simultaneously coat and dry the particles,inlet of fluidization air was at 50℃ .Moreover,Monte Carlo simulations of coating with small aerosol and large spray droplets were *** to dramatically smaller building blocks,ultrathin particle coating of high-resolution(very small layer thickness)can be attained with the new aerosol process,with the potential of even going *** coverage of particles is reached substantially faster than in the conv entional process,so that material dema nd is much lower and sensitive materials can be processed in short reside nee *** yield of around 30%was much higher than expected,that is considered to be technically viable and may be enhanced by the recycling of entrained solids or better equipment design.

关键词： Aerosol Fluidized bed Particle Submicron droplet Ultrathin coating

Dual Control Strategy for Grid-tied Battery Energy Storage Systems to Comply with Emerging Grid Codes and Fault Ride Through Requirements

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 977-988页

作者： Maxime Berger Ilhan Kocar evangelos Farantatos Aboutaleb Haddadi Department of Electrical Engineering Polytechnique MontréalMontréalCanada Electric Power Research Institute(EPRI) Palo AltoUSA

Battery energy storage systems(BESSs)need to comply with grid code and fault ride through(FRT)requirements during disturbances whether they are in charging or discharging *** literature has shown that constant charging current control of BESSs in charging mode can prevent BESSs from complying with emerging grid codes such as the German grid code under stringent unbalanced fault *** address this challenge,this paper proposes a new FRTactivated dual control strategy that consists of switching from constant battery current control to constant DC-link voltage control through a positive droop *** results show that the strategy ensures proper DC-link voltage and current management as well as adequate control of the positive-and negative-sequence active and reactive currents according to the grid code *** is also shown that the proposed FRT control strategy is tolerant to initial operating conditions of BESS plant,grid code requirements,and fault severity.

关键词： Battery energy storage system inverter-based resource fault ride through electromagnetic transient