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Interaction phenomena between liquid droplets and hot particles—Captured via high-speed camera

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Particuology 2009年第4期7卷 260-263页

作者： sebastian Gehrke Karl-Ernst Wirth Institute of Particle Technology Cauerstrasse 4Erlangen 91058Germany

The interaction of evaporating droplets and hot catalyst particles plays a major role in heterogeneously catalysed reactions. The liquid feed is injected into a gas-solid flow and is mixed with the catalyst. The interaction phenomena determine the evaporation time which should be minimised to keep the reactor vessel small. First measurements with a bed of fixed hot FCC-particles （fluid catalytic cracking） and two model fluids have been conducted. The interactions of ethanol and water droplets with the hot bed surface were captured via a high-speed camera. While the ethanol droplet developed a stable steam cushion due to Leidenfrost phenomena, water showed intense interaction and steam explosions which induced repulsion and atomisation of the droplet.

关键词： Particle-droplet-interaction Leidenfrost phenomenon Direct heat transfer Liquid-feed-injection

The impact of dielectrics on the electrical capacity, concentration, efficiency ozone generation for the plasma reactor with mesh electrodes

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Plasma Science and Technology 2018年第8期20卷 89-95页

作者： Ernest GNAPOWSKI sebastian GNAPOWSKI Jaroslaw PYTKA University College of Enterprise and Administration in Lublin Bursaki 12 20-150 Lublin Poland Fundamentals of Technology Faculty Lublin University of Technology ul. Nadbystrzycka 38 20-618 Lublin Poland Faculty of Mechanical Engineering Lublin University of Technology ul. Nadbystrzycka 36 20-618 Lublin Poland

This paper presents experimental results concerning the effect of dielectric type on ozone concentration and the efficiency of its generation in plasma reactor with two mesh *** types of dielectric solid were used in the study; glass, micanite and Kapton insulating foil. The experiments were conducted for voltage ranges from 2.3 to 13 k V. A plasma reactor equipped with two 0.3×0.3 mm^2 mesh electrodes made of acid resistant AISI 304 mesh was used in the experiments. The influence of the dielectric type on the concentration and efficiency of ozone generation was described. The resulting maximum concentration of the ozone was about 2.70–9.30 g O3 m^-3, depending on the dielectrics used. The difference between the maximum and the minimum ozone concentration depends on the dielectric used,this accounts for 70% at the variance. The reactor capacity has also been described in the paper; total Ct and dielectric capacitance Cd depending on the dielectric used and its thickness.

关键词： ozone generation efficiency dielectric mesh electrode ozone generator electrical capacity

Occult hepatitis B—the result of the host immune response interaction with different genomic expressions of the virus

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World Journal of Clinical Cases 2022年第17期10卷 5518-5530页

作者： George sebastian Gherlan Department of Infectious Diseases “Carol Davila”University of Medicine and PharmacyBucharest 030303Romania Department of Infectious Diseases “Dr.Victor Babes”Hospital of Infectious and Tropical DiseasesBucharest 030303Romania

With over 40 years of history,occult hepatitis B infection(OBI)continues to remain an important and challenging public health *** as the presence of replication-competent hepatitis B virus(HBV)DNA(i.e.,episomal HBV covalently closed circular DNA)in the liver and/or HBV DNA in the blood of people who test negative for hepatitis B surface antigen(HBsAg)in currently available assays,OBI is currently diagnosed using polymerase chain reaction(PCR)and real-time PCR ***,all efforts should be made to exclude a false negative HBsAg in order to completely follow the definition of *** recent years,significant advances have been made in understanding the HBV lifecycle and the molecular mechanisms that lead to the persistence of the virus in the occult *** factors are mainly related to the host immune system and,to a smaller proportion,to the *** innate and adaptive immune responses are important in HBV infection management,and epigenetic changes driven by host mechanisms(acetylation,methylation,and microRNA implication)are added to such *** greater genetic variability in the S gene of HBV isolated from OBIs was found compared with overt infection,the mechanisms of OBI are not mainly viral mutations.

关键词： Hepatitis B virus Occult hepatitis B Covalently closed circular DNA Epigenetic factors Immune factors MicroRNA

Robustness analysis metrics for worldwide airport network：A comprehensive study

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Chinese Journal of Aeronautics 2017年第2期30卷 500-512页

作者： Sun Xiaoqian Volker Gollnick sebastian Wandelt School of Electronic and Information Engineering Beihang University 100083 Beijing China Beijing Key Laboratory for Network-based Cooperative A TM Beijing 100083 China Beijing Laboratory for General Aviation Technology Beijing 100083 China Institute of Air Transportation Systems German Aerospace Center Blohmstrasse 18 21079 Hamburg Germany

Robustness of transportation networks is one of the major challenges of the 21 st *** paper investigates the resilience of global air transportation from a complex network point of view,with focus on attacking strategies in the airport network,i.e.,to remove airports from the system and see what could affect the air traffic system from a passenger＇s ***,we identify commonalities and differences between several robustness measures and attacking strategies,proposing a novel notion of functional robustness：unaffected passengers with *** apply twelve attacking strategies to the worldwide airport network with three weights,and evaluate three robustness *** find that degree and Bonacich based attacks harm passenger weighted network *** evaluation is geared toward a unified view on air transportation network attack and serves as a foundation on how to develop effective mitigation strategies.

关键词： Air transportation systems resilience Airport network Attacking strategy Robustness measure

The essence of bidirectional programming

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Science China(Information Sciences) 2015年第5期58卷 76-96页

作者： FISCHER sebastian HU ZhenJiang PACHECO Hugo Department of Computing Science Christian-Albrechts-University of Kiel Information Systems Architecture Research Division National Institute of Informatics Department of Informatics The Graduate University for Advanced Studies (SOKENDAI) School of Electronics Engineering and Computer Science Peking University Department of Computer Science Cornell University

Bidirectional transformations(BXs), programs with a forward transformation and a backward transformation that maintain consistency between input and output, are routinely written in ways that do not let programmers specify their behavior completely. Several bidirectional programming languages exist to aid programmers in writing BXs with increased maintainability but decreased expressiveness. Such languages allow programmers to write BXs as one program for both directions, which is easier to maintain than separate programs for each direction. However, the maintainability provided by existing bidirectional languages comes at the cost of expressiveness because the ambiguity of synchronization is solved by default strategies which are hidden from programmers. The programmers’ inability to influence synchronization strategies has led to the proposal of a vast number of approaches that consider tailor-made synchronization strategies for particular *** this paper, we argue that such ambiguity is essential for BX and advocate that the synchronization strategy should not be hidden from programmers but considered from the start. We propose a novel approach to specifying so-called well-behaved bidirectional programs by their backward transformations, capable of expressing all aspects of a BX while retaining maintainability. Soundness of our approach results from a systematic analysis, based on existing mathematical concepts, of the instrumental laws of well-behaved BXs. We show that well-behaved BXs are uniquely determined by their backward transformations and corresponding forward transformations can be obtained for free.

关键词： bidirectional transformation software adaption and coevolution bidirectional programming

Deep Drawing with Local Hardening on Digital Multi-axis Servo Press

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1490-1495页

作者： sebastian Kriechenbauer Reinhard Mauermann Dirk Landgrebe Fraunhofer IWU

The paper discusses a new drawing technology, based on a synchronized movement of ram and cushion with multiple bending operations in alternating directions called ＂bi-directional deep drawing（BDD）.＂ The goal is to avoid local thinning by strengthening the weak point using local hardening. BDD operations are realized before the conventional deep drawing process. This results in a local strain hardening at the weak point of the workpiece, which is usually located at the bottom punch radius. Two major aspects have to be given attention due to the high number of process parameters. On the one hand, for process design, it is helpful to have a tool by means of which it is possible to simultaneously create both the machine program for the servo press and the initial configuration for the process simulation. From the authors＇ point of view, this complexity can only be represented by a numerical analysis method, on the other hand. Consequently, both aspects are given attention in this paper.

关键词： Bi-directional deep drawing(BDD) Local hardening Servo press Pulsation

Exploiting global information in complex network repair processes

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Chinese Journal of Aeronautics 2017年第3期30卷 1086-1100页

作者： Tianyu WANG Jun ZHANG sebastian WANDELT School of Electronic and Information Engineering Beihang University 100083 Beijing ChinaBeoing Key Laboratory Jor Network-based Cooperative ATM 100083 Beijing China

Robustness of complex networks has been studied for decades,with a particular focus on network *** on network repair,on the other hand,has been conducted only very lately,given the even higher complexity and absence of an effective evaluation metric.A recently proposed network repair strategy is self-healing,which aims to repair networks for larger components at a low cost only with local *** this paper,we discuss the effectiveness and efficiency of self-healing,which limits network repair to be a multi-objective optimization problem and makes it difficult to measure its *** leads us to a new network repair evaluation *** the time complexity of the computation is very high,we devise a greedy ranking *** on both real-world and random networks show the effectiveness of our new metric and repair *** study contributes to optimal network repair algorithms and provides a gold standard for future studies on network repair.

关键词： Complex network Global information Greedy ranking Optimality Self-healing

Experimental and computational analysis of the coolant distribution considering the viscosity of the cutting fluid during machining with helical deep hole drills

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Advances in Manufacturing 2022年第2期10卷 235-249页

作者： Ekrem Oezkaya sebastian Michel Dirk Biermann Institute of Machining Technology Dortmund University of Technology(TU Dortmund)Dortmund 44227Germany

An experimental analysis regarding the distribution of the cutting fluid is very difficult due to the inaccessibility of the contact zone within the bore ***,suitable simulation models are necessary to evaluate new tool designs and optimize drilling *** this paper the coolant distribution during helical deep hole drilling is analyzed with high-speed *** particles are added to the cutting fluid circuit bya developed high-pressure mixing *** the evaluation of suitable particle size,particle concentration and coolant pressure,a computational fluid dynamics(CFD)simulation is validated with the experimental *** comparison shows a very good model quality with a marginal difference for the flow velocity of 1.57%between simulation and *** simulation considers the kinematic viscosity of the *** results show that the fluid velocity in the chip flutes is low compared to the fluid velocity at the exit of the coolant channels of the tool and drops even further between *** velocity and the flow pressure directly at the cutting edge decrease to such an extent that the fluid cannot generate a sufficient cooling or *** the CFD simulation a deeper understanding of the behavior and interactions of the cutting fluid is *** on these results further research activities to improve the coolant supply can be carried out with great potential to evaluate new tool geometries and optimize the machining process.

关键词： Computational fluid dynamics(CFD)analysis:Viscosity-Tracermicro particles Fluidbehavior Helical deep hole drilling

Conductivity improvement of Ce_(0.8)Gd_(0.2)O_(1.9) solid electrolyte

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Journal of Rare Earths 2009年第4期27卷 655-660页

作者： sebastian Molin Maria Gazda Piotr Jasinski Faculty of Electronics Telecommunications and Informatics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland Faculty of Applied Physics and Mathematics Gdansk University of Technology ul.Narutowicza 11/12 80-952 Gdansk Poland

Solid oxide fuel cells based on doped cefia electrolytes offer operating temperatures of -600℃. During recent years much atten- tion was aimed at successful powder preparation with high sinter activity and high conductivity. The properties of ceria electrolyte are very sensitive to impurities introduced during powder and electrolyte fabrication. One of the most successful and commercially available processes for the production of clean powders is based on the addition of several percent metallic cations that will react with impurities and segregate into the triple points of grain boundaries. In this work the results obtained from doping of CGO20 by 2% Ca and prepared by different routes were presented. The way of introducing Ca seemed to play an important role.

关键词： rare earth solid elecllolyte electrical properties impedance spectroscopy fuel cell solid oxide fuel cells (SOFC)