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Microbial diversity and oil biodegradation potential of northern Barents Sea sediments

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Journal of Environmental Sciences 2024年第12期146卷 283-297页

作者： Song-Can Chen Florin Musat Hans-hermann Richnow Martin Krüger Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research–UFZLeipzigGermany Division of Microbial Ecology Department of Microbiology and Ecosystem ScienceUniversity of ViennaViennaAustria Department of Biology Section for MicrobiologyAarhus UniversityAarhusDenmark Department of Molecular Biology and Biotechnology Faculty of Biology and GeologyBabeș-Bolyai UniversityCluj-NapocaRomania Federal Institute for Geosciences and Natural Resources(BGR) Stilleweg 230655HannoverGermany

The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil *** crucial elements of Arctic environments,benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming ***,the Arctic benthic microbiomes are among the least explored biomes on the *** we combined geochemical analyses,incubation experiments,and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents *** results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere,such as Chloroflexi,Atribacteria,and *** topmost benthic communities were spatially structured by sedimentary organic carbon,lacking a clear distinction among geographic *** increasing sediment depth,the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of *** benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic *** of surface sediments with crude oil led to proliferation of several genera from the so-called rare *** include Alkalimarinus and Halioglobus,previously unrecognized as hydrocarbon-degrading genera,both harboring the full genetic potential for aerobic alkane *** findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.

关键词： Arctic Deep-sea sediments Benthic microbiomes Biodiversity Oil biodegradation

Geoscience material structures prediction via CALYPSO methodology

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Chinese Physics B 2019年第10期28卷 38-49页

作者： Andreas hermann Centre for Science at Extreme Conditions and SUPA School of Physics and Astronomy The University of Edinburgh

Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology can help shed light on the transformations materials undergo at the extreme conditions inside planets. The discussion focuses on three areas:(i) the propensity of iron to form compounds with volatile elements at planetary core conditions(important to understand the chemical makeup of Earth's inner core),(ii) the chemistry of mixtures of planetary ices(relevant for the mantle regions of giant icy planets), and(iii) examples of mantle minerals. In all cases the abilities and current limitations of crystal structure prediction are discussed across a range of example studies.

关键词： crystal structure prediction core materials planetary ices hydrous minerals

Running‑In Behavior of Wet Multi‑plate Clutches:Introduction of a New Test Method for Investigation and Characterization

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 152-160页

作者： Katharina Voelkel hermann pflaum Karsten Stahl Gear Research Centre(FZG) Technical University of MunichGarchingGermany

Wet multi-plate clutches are relevant components of modern drivetrain applications,not only in terms of function but also safety and *** at the beginning of their lifetime,distinct changes of the friction behavior may occur and make the actuation of the clutch *** transcript describes the typical running-in behavior of wet multi-plate clutches and gives a general definition for running-in of ***,a new test method to systematically investigate the running-in behavior of clutches is *** test method contains a test procedure to characterize the running-in behavior on different load ***,a multi-stage procedure to evaluate and characterize the running-in behavior of clutches with mathematical approaches and new characteristic values is *** quality of the test method is demonstrated on the example of three different tribological systems from dual clutch transmissions(DCT)and automatic transmissions(AT)application using paper friction linings.

关键词： Clutch Running-in Test method Paper friction lining

Blow-up behavior of Hammerstein-type delay Volterra integral equations

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Frontiers of Mathematics in China 2013年第2期8卷 261-280页

作者： Zhanwen YANG hermann BRUNNER Science Research Center Academy of Fundamental and Interdisciplinary Science Department of Mathematics Harbin Institute of Technology Harbin 150001 China Department of Mathematics Hong Kong Baptist University Hong Kong SAR China Department of Mathematics and Statistics Memorial University of NewfoundlandSt. John's NL AIC 557 Canada

We consider the blow-up behavior of Hammerstein-type delay Volterra integral equations （DVIEs）. Two types of delays, i.e., vanishing delay （pantograph delay） and non-vanishing delay （constant delay）, are considered. With the same assumptions of Volterra integral equations （VIEs）, in a similar technology to VIEs, the blow-up conditions of the two types of DVIEs are given. The blow-up behaviors of DVIEs with non-vanishing delay vary with different initial functions and the length of the lag, while DVIEs with pantograph delay own the same blow-up behavior of VIEs. Some examples and applications to delay differential equations illustrate this influence.

关键词： Delay Volterra integral equation (DVIE) non-vanishing delay vanishing delay blow-up of solution

A SPECTRAL METHOD FOR PANTOGRAPH-TYPE DELAY DIFFERENTIAL EQUATIONS AND ITS CONVERGENCE ANALYSIS

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Journal of Computational Mathematics 2009年第2期27卷 254-265页

作者： Ishtiaq Ali hermann Brunner Institute of Computational Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Mathematics COMSA TS Institute of Information Technology IslamabadPakistan hermann Brunner Department of Mathematics and Statistics Memorial University of NewfoundlandSt.John’sCanada Department of Mathematics Hong Kong Baptist UniversityHong KongChina

We propose a novel numerical approach for delay differential equations with vanishing proportional delays based on spectral methods. A Legendre-collocation method is employed to obtain highly accurate numerical approximations to the exact solution. It is proved theoretically and demonstrated numerically that the proposed method converges exponentially provided that the data in the are smooth. given pantograph delay differential equation

关键词： Spectral methods Legendre quadrature formula Pantograph-type delay differential equations Error analysis Exponential convergence

Overview of Particles and Bubbles in Continuously Cast Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 211-219页

作者： Karl-hermann TACKE AG der Dillinger Hüttenwerke P.O. Box 1580 D-66748 Dillingen/Saar Germany

This paper gives an overview of phenomena associated with particles and bubbles in continuously cast steel. During steel processing from deoxidation to solidification the inclusion population undergoes changes with opportunities of removal. Flotation is an important separation mechanism. Inclusion particles may accumulate in the solidifying strand, thus forming enriched bands, which depend on the type of casting machine. Bubbles are created during inert gas injection. They also change in size, can float out, but also form accumulation bands. The interaction of bubbles and particles is discussed. Internal structure that recently has been observed on the inner surface of bubbles will be reviewed.

关键词： continuous casting solidification inclusions particles agglomeration accumulation bands gas injection bubbles attachment flotation inner surface wave rings terraces

Simulating orthokinetic heterocoagulation and cluster growth in destabilizing suspensions

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Particuology 2017年第2期15卷 117-128页

作者： Fabian Billow hermann Nirschl Willy Dorfler Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology 76131 Karlsruhe Germany Institute for Applied and Numerical Mathematics Karlsruhe Institute of Technology 76131 Karlsruhe Germany

Using direct numerical simulation, we investigate the coagulation behavior of non-Brownian colloidal particles as exemplified by Al2O3 particles. This yields the so-called capture efficiency, for which we give an analytical expression, as well as other time-dependent variables such as the cluster growth rate. Instead of neglecting or strongly approximating the hydrodynamic interactions between particles, we include hydrodynamic and non-hydrodynamic interactions in a Stokesian dynamics approach and a comprehensive modeling of the interparticle forces. The resulting parallelized simulation framework enables us to investigate the dynamics of polydisperse particle systems composed of several hundred particles at the same high level of modeling we used for a close investigation of the coagulation behavior of two unequal particles in shear flow. Appropriate cluster detection yields all the information about large destabilizing systems, which is needed for models used in flow-sheet simulations. After non-dimensionalization, the results can be generalized and applied to other systems tending to secondary coagulation

关键词： Destabilization Coagulation Capture efficiency Al2O3 Cluster detection Stokesian dynamics

Fused in sarcoma-amyotrophic lateral sclerosis as a novel member of DNA single strand break diseases with pure neurological phenotypes

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Neural Regeneration Research 2021年第1期16卷 110-112页

作者： Marcel Naumann Julian Laubenthal Andreas hermann Translational Neurodegeneration Section“Albrecht-Kossel” Department of NeurologyUniversity Medical Center RostockUniversity of RostockRostockGermany german Center for Neurodegenerative Diseases(DZNE)Rostock/Greifswald Center for Transdisciplinary Neurosciences Rostock(CTNR)University Medical Center RostockUniversity of RostockRostockGermany

Accumulation of DNA damage and genomic instability are believed to have crucial effects in neurodegenerative conditions such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,premature aging diseases as well as amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD).Until recently these studies were largely correlative in nature,though raising the possibility that defects in the DNA damage response(DDR)underlie neurodegenerative diseases.

关键词： diseases Huntington amyotrophic

Influence of drag laws on pressure and bed material recirculation rate in a cold flow model of an 8 MW dual fluidized bed system by means of CPFD

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Particuology 2018年第1期16卷 70-81页

作者： Stephan Kraft Friedrich Kirnbauer hermann Hofbauer Bioenergy 2020+ GmbH Wiener Strasse 49 A- 7540 Gussing Austria TU Wien Institute of Chemical Engineering Getreidemarkt 9/166 Vienna Austria

A cold flow model of an 8 MW dual fluidized bed （DFB） system is simulated using the commercial compu- tational particle fluid dynamics （CPFD） software package Barracuda. The DFB system comprises a bubbling bed connected to a fast fluidized bed with the bed material circulating between them. As the hydrodynam- ics in hot DFB plants are complex because of high temperatures and many chemical reaction processes, cold flow models are used. Performing numerical simulations of cold flows enables a focus on the hydro- dynamics as the chemistry and heat and mass transfer processes can be put aside. The drag law has a major influence on the hydrodynamics, and therefore its influence on pressure, particle distribution, and bed material recirculation rate is calculated using Barracuda and its results are compared with experimental results. The drag laws used were energy-minimization multiscale （EMMS）, Ganser, Turton-Levenspiel, and a combination of Wen-Yu]Ergun. Eleven operating points were chosen for that study and each was calculated with the aforementioned drag laws. The EMMS drag law best predicted the pressure and dis- tribution of the bed material in the different parts of the DFB system. For predicting the bed material recirculation rate, the Ganser drag law showed the best results. However, the drag laws often were not able to predict the experimentally found trends of the bed material recirculation rate. Indeed, the drag law significantly influences the hydrodynamic outcomes in a DFB system and must be chosen carefully to obtain meaningful simulation results. More research may enable recommendations as to which drag law is useful in simulations ofa DFB system with CPFD.

关键词： Cold flow modeling Fluidization Computational particle fluid dynamics(CPFD) simulation Dual fluidized bed Computational fluid dynamics