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Replacement of annular domain with trapezoidal domain in computational modeling of nonaqueous-phase-liquid dissolution-front propagation problems

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Journal of Central South University 2015年第5期22卷 1841-1846页

作者：赵崇斌 Thomas POULET klaus REGENAUER-LIEB Computational Geosciences Research Centre Central South University CSIRO Division of Earth Science and Resource Engineering P.O.Box 1130 Bentley WA 6102 Australia School of Earth and Environment The University of Western Australia

In order to simulate the instability phenomenon of a nonaqueous phase liquid(NAPL) dissolution front in a computational model, the intrinsic characteristic length is commonly used to determine the length scale at which the instability of the NAPL dissolution front can be initiated. This will require a huge number of finite elements if a whole NAPL dissolution system is simulated in the computational model. Even though modern supercomputers might be used to tackle this kind of NAPL dissolution problem, it can become prohibitive for commonly-used personal computers to do so. The main purpose of this work is to investigate whether or not the whole NAPL dissolution system of an annular domain can be replaced by a trapezoidal domain, so as to greatly reduce the requirements for computer efforts. The related simulation results have demonstrated that when the NAPL dissolution system under consideration is in a subcritical state, if the dissolution pattern around the entrance of an annulus domain is of interest, then a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution ***, if the dissolution pattern away from the vicinity of the entrance of an annulus domain is of interest, then a trapezoidal domain can be used to replace an annular domain in the computational simulation of the NAPL dissolution system. When the NAPL dissolution system under consideration is in a supercritical state, a trapezoidal domain cannot be used to replace an annular domain in the computational simulation of the NAPL dissolution system.

关键词： nonaqueous phase liquid(NAPL) trapezoidal domain computational simulation dissolution front instability

Amine reclaiming technologies in post-combustion carbon dioxide capture

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Journal of Environmental Sciences 2015年第1期27卷 276-289页

作者： Tielin Wang Jon Hovland klaus J.Jens Telemark University College Tel-Tek Porsgrunn 3918 Norway

Amine scrubbing is the most developed technology for carbon dioxide（CO2） *** of amine solvents due to the presence of high levels of oxygen and other impurities in flue gas causes increasing costs and deterioration in long term performance,and therefore purification of the solvents is needed to overcome these problems. This review presents the reclaiming of amine solvents used for post combustion CO2capture（PCC）. Thermal reclaiming, ion exchange, and electrodialysis, although principally developed for sour gas sweetening, have also been tested for CO2 capture from flue *** three technologies all have their strengths and weaknesses, and further development is needed to reduce energy usage and costs. An expected future trend for amine reclamation is to focus on process integration of the current reclaiming technologies into the PCC process in order to drive down costs.

关键词： Carbon dioxide capture Amine reclaiming Distillation Ion exchange Electrodialysis

IEC 61850 as Backbone for Smart PAC Systems

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CSEE Journal of Power and Energy Systems 2016年第4期2卷 15-22页

作者： klaus-Peter Brand ABB Switzerland PGGA-AUABaden 5400Switzerland

This paper discusses a working definition of smartness in protection,automation and control systems(PACS)in substations.A summary is given about the standard IEC 61850 features that support smartness,i.e.,the data model,the multiple communication services,and the system configuration description language(SCL).With help of known examples of application functions for control,supervision,and protection,the building of smart systems out of the modules of IEC 61850 is *** the possible architectures,the standardized redundancy is *** process bus is exploited in detail since it is seen by users as the core of a smart *** this context,attention is given also to the time synchronization in theµs range over the communication network,a rather new part of the *** the last part,all features are summarized and it is concluded that IEC 61850 may really be named the backbone for smart PAC systems.

关键词： Automation communication control IEC 61850 process bus protection smart systems substations

Obesity and its influence on liver dysfunction,morbidity and mortality after liver resection

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Hepatobiliary Surgery and Nutrition 2023年第5期12卷 704-714,I0018页

作者： Stephanie Kampf Michael Sponder Fabian Fitschek Daniel Laxar Martin Bodingbauer Carina Binder Stefan Stremitzer klaus Kaczirek Christoph Schwarz Division of Visceral Surgery Department of General SurgeryMedical University of ViennaViennaAustria Division of Cardiology Department of Internal Medicine IIMedical University of ViennaViennaAustria Clinical Institute of Pathology Medical University of ViennaViennaAustria

Background:Obesity and associated steatosis is an increasing health problem *** influence on post-hepatectomy liver failure(PHLF)and after liver resection(LR)is still ***:Patients who underwent LR were investigated and divided into three groups[normal weight:body mass index(BMI)18.5-24.9 kg/m2,overweight:BMI 25.0-29.9 kg/m2,obese:BMI≥30 kg/m2]in this retrospective *** aim of this study was to assess the influence of BMI and nonalcoholic steatohepatitis(NASH)on PHLF and ***:Of 888 included patients,361(40.7%)had normal weight,360(40.5%)were overweight,167(18.8%)were *** age was 62.5 years(IQR,54-69 years).The primary indication for LR was colorectal liver metastases(CLM)(n=366,41.2%).NASH was present in 58(16.1%)of normal weight,84(23.3%)of overweight and 69(41.3%)of obese patients(P<0.001).PHLF occurred in 16.3%in normal weight,15.3%in overweight and 11.4%in obese patients(P=0.32).NASH was not associated with *** was no association between patients’weight and the occurrence of postoperative complications(P=0.45).At multivariable analysis,solely major LR[odds ratio(OR):2.7,95%confidence interval(CI):1.83-4.04;P<0.001]remained a significant predictor for ***:Postoperative complications and PHLF are comparable in normal weight,overweight and obese patients and LRs using modern techniques can be safely performed in these patients.

关键词： Obesity liver resection(LR) post-hepatectomy liver failure(PHLF) morbidity

Actuation of Liquid Flow by Guided Acoustic Waves on Punched Steel Tapes with Protruding Loops

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Journal of Bionic Engineering 2021年第3期18卷 534-547页

作者： Alexander Backer Johannes Landskron klaus Stefan Drese Gerhard Lindner Institute of Sensor and Actuator Technology Coburg University of Applied Sciences and Arts96450 CoburgGermany

In a biomimetic approach the feasibility of liquid flow actuation by vibrating protruding structures excited via guided acoustic waves is *** by periodically beating cilia the loop part of a punched metallic hook-and-loop tape with tilted protruding loops was used as a waveguide for plate waves in *** waves were excited in the frequency range of 110 Hz to 220 Hz by directly coupling the tape to a loudspeaker membrane.A flow generated in the tilt direction of the loops with velocities up to 60 mm s 1 was visualized by ink droplets deposited on the *** phenomenon persisted,when the protruding length of the loops was reduced by decreasing the protrusion ***,after closing the punch holes near the loops with sticking tape streaming could not be observed any *** same happened with open punch holes when the ink was replaced by ***-frequency acoustic streaming around vibrating sharp edges is proposed as an explanation for the observed *** are expected with respect to the modification of flow profiles and the enhancement of transport processes along and across liquid-solid boundaries.

关键词： bio-inspired guided acoustic waves metallic hook-and-loop tape artificial cilia liquid propulsion Copyright

Low-Temperature Plasticity of Naturally Deformed Calcite Rocks

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Acta Geologica Sinica(English Edition) 2002年第3期76卷 292-299页

作者：刘俊来 klaus WEBER Department of Geology Jilin University Changchun 130061 China Institute of Geololgy and Dynamics of the Lithoshere University of GoettingenGoettingen 37077Germany

Optical, cathodoluminescence and transmission electron microscope (TEM)analyses were conducted on four groups of calcite fault rocks, a cataclastic limestone, cataclasticcoarse-grained marbles from two fault zones, and a fractured mylonite. These fault rocks showsimilar microstructural characteristics and give clues to similar processes of rock *** are characterized by the structural contrast between macroscopic cataclastic (brittle) andmicroscopic mylonitic (ductile) microstructures. Intragranular deformation microstructures (*** twins, kink bands and microfractures) are well preserved in the deformed grains inclasts or in primary rocks. The matrix materials are of extremely fine grains with diffusivefeatures. Dislocation microstructures for co-existing brittle deformation and crystalline plasticitywere revealed using TEM. Tangled dislocations are often preserved at the cores of highly deformedclasts, while dislocation walls form in the transitions to the fine-grained matrix materials andfree dislocations, dislocation loops and dislocation dipoles are observed both in the deformedclasts and in the fine-grained matrix materials. Dynamic recrystallization grains from subgrainrotation recrystallization and subsequent grain boundary migration constitute the major parts of thematrix materials. Statistical measurements of densities of free dislocations, grain sizes ofsubgrains and dynamically recrystallized grains suggest an unsteady state of the rock *** and cathodoluminescence analyses prove that fluid activity is one of the major partsof faulting processes. Low-temperature plasticity, and thereby induced co-existence of macroscopicbrittle and microscopic ductile microstructures are attributed to hydrolytic weakening due to theinvolvement of fluid phases in deformation and subsequent variation of rock rheology. Duringhydrolytic weakening, fluid phases, e.g. water, enhance the rate of dislocation slip and climb, andincrea

关键词： calcite rocks low-temperature deformation fluid phase fracturing crystalline plasticity

NF-κB Regulates B-Cell-Derived Nerve Growth Factor Expression

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Cellular & Molecular Immunology 2006年第1期3卷 63-66页

作者： klaus Heese Noriko Inoue Tohru Sawada Department of Molecular and Cell Biology School of Biological SciencesNanyang Technological University60 Nanyang DriveSingapore 637551Singapore BF Research Institute Inc.Itoyoshi Building 2012-5-9 DoshomachiChuo-kuOsaka 541-0045Japan BF Research Institute Inc. Itoyoshi Building 2012-5-9 DoshomachiChuo-kuOsaka 541-0045Japan

In the mammalian brain, four neurotrophins have been identified： nerve growth factor （NGF）, brain-derived neurotrophic factor （BDNF）, neurotrophin-3 （NT-3） and neurotrophin-4/5 （NT-4/5）. NGF exerts an important role in the development and functions of the central and peripheral nervous system. However, it has recently been documented that several types of immune cells, such as mast ceils, iymphocytes, basophils and eosinophils, produce, store and release NGF. Accumulating preclinical and clinical data indicate that dysfunctions of NGF and the other neurotrophins may contribute to impaired immune responses and concentration of NGF frequently correlates with disease severity. Thus, the aim of this study was to elucidate the potential signaling mechanisms of cytokineneurotrophins interactions contributing to increased NGF levels. Our data show that the transcription factor NF-κB plays a pivotal role in regulating B-cell-derived NGF expression.

关键词： immune system inflammation interleukin NGF neurotrophin

The impact of autophagy in spermiogenesis

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Asian Journal of Andrology 2017年第6期19卷 617-618页

作者： Nihan Ozturk klaus Steger Undraga Schagdarsurengin Clinic of Urology Pediatric Urology and AndrologySection Molecular Andrology Justus-Liebig-UniversityGiessen Schubertstrasse 81 35392 GiessenGermany.

Autophagy is an evolutionarily .conserved self-digestion process whichis essential to keep basal homeostasis in a cell. During this process, degradation and recycling of many cytoplasmic components including the long-lived, unnecessary or aggregated proteins and damaged organelles is achieved through lysosomal machinery. Autophagy has a critical role for lower eukaryotic organisms such as yeast to survive and adapt to nutrient starvation conditions. In addition to this primary function, autophagy appears as a crucial mechanism for cell differentiation and development enabling the cells to modify their content and morphology in response to environmental and hormonal cues. A recent study by Shang et all shed more light on the molecular mechanisms of how autophagy regulates spermiogenesis.

关键词： impact autophagy spermiogenesis

Migration routes and strategies of Grey Plovers (Pluvialis squatarola) on the East Atlantic Flyway as revealed by satellite tracking

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Avian Research 2019年第3期10卷 305-318页

作者： klaus-Michael Exo Franziska Hillig Franz Bairlein Institute of Avian Research Vogelwarte Helgoland

Background:While the general migration routes of most waders are known,details concerning connectivity between breeding grounds, stopover sites and wintering grounds are often *** information is critical from the conservation perspective and necessary for understanding the annual *** are especially needed to identify key stopover sites in remote regions. Using satellite transmitters, we traced spring and autumn migration routes and connectivity of Grey Plovers on the East Atlantic *** findings also revealed the timing,flight speed, and duration of migrations. Methods:We used ARGOS satellite transmitters to track migration routes of 11 Grey Plovers that were captured at the German Wadden Sea where they had stopped during *** were monitored for up to 3 years,***:Monitoring signals indicated breeding grounds in the Taimyr and Yamal regions;important staging sites on the coasts of the southern Pechora Sea and the Kara Sea;and wintering areas that ranged from NW-Ireland to Guinea *** average distance traveled from wintering grounds to breeding grounds was 5534 km. Migration duration varied between 42 and 152 days;during this period birds spent about 95% of the time at staging *** spring most plovers crossed inland Eastern Europe, whereas in autumn most followed the *** all of the birds departed during favorable wind conditions within just 4 days (27-30 May) on northward migration from the Wadden *** spring birds migrated significantly faster between the Wadden Sea and the Arctic than on return migration in autumn (12 vs.37 days),with shorter stopovers during the northward ***:Our study shows that satellite tags can shed considerable light on migration strategies by revealing the use of different regions during the annual cycle and by providing detailed quantitative data on population connectivity and migration timing.

关键词： Annual cycle Long-distance migration Migration speed Migration strategy Migration timing Satellite transmitters Shorebirds Tracking Stopover