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Practical numerical simulation of the effect of TBM process pressures on soil displacements through 3D shift iteration

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Underground Space 2018年第4期3卷 297-309页

作者： Benno ring Marc Comulada ring–Consultancy in Tunnelling Alpenstr.582131 StockdorfGermany Maidl Tunnelconsultants Goethestr.7480336 MunichGermany

A 3D-finite element model is illustrated that allows for the iterative simulation of the shield drive with its face and grouting pressures by shifting the determined stresses and displacements after each calculation *** are performed for the tunneling of Rio de Janeiro’s Line 4 and compared to the results of analytical limit equilibrium analyses and monitoring results of the actual TBM-drive.

关键词： Settlements TBM pressures 3D-Finite element method Numerical simulation Shift iteration

A rotating α-chain in the nucleus 12C

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 14-15页

作者： Peter ring Physics Department Technical University Munich State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University

Because of the strong nuclear force among protons and neutrons,α-particles form a stable configuration not only in free space, but also in very light nuclei. Even in unstable configurations of heavy and super-heavy nuclei,α-decay is often observed. Obviously there is a high probability for the formation of anα-particle in such systems, which tunnels through the Coulomb barrier as a combined particle.

关键词： A rotating chain in the nucleus

Carnobacteria in fish

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Aquaculture and Fisheries 2024年第2期9卷 193-205页

作者： Einar ring Norwegian College of Fishery Science Faculty of BioscienceFisheries and EconomicsUiT The Arctic University of NorwayTromsø9010Norway

Carnobacterium is a genus of Gram-positive bacteria,within family Carnobacteriaceae,and they are catalase-and oxidase-negative,non-sporing bacteria with properties such as CO_(2)and L(+)-lactic acid production from glucose,but they are not able to grow on acetate *** are ubiquitous lactic acid bacteria and have been isolated from both cold and temperate environments,and they are identified as components of the microbiota in the gastrointestinal(GI)tract of salmonids and several other fish species of which Carnobacterium(piscicola)maltaromaticum,Carnobacterium mobile,Carnobacterium divergens,Carnobacterium alterfunitum,and Carnobacterium inhibens are *** the last two decades several studies have revealed that carnobacteria can act as probiotics to promote health benefits of fish,as well as they in ex vivo studies to some extent can out-compete *** addition to beneficial effects,information is available that some carnobacteria species causing fish *** aim of the present review is to present an updated overview of Carnobacterium in fish,with focus on their presence in the GI tract,their use as probiotic supplement and general information on pathogenic carnobacteria.

关键词： Carnobacterium Gastrointestinal tract Probiotics Fish health Pathogenic

New Developments in Thermo-Chemical Diffusion Processes

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材料热处理学报 2004年第5期25卷 13-19页

作者： bernd Edenhofer Ipsen International GmbH Kleve Germany

Thermo-chemical diffusion processes like carburising, nitriding and boronizing play an important part in modern manufacturing technologies. They exist in many varieties depending on the type of diffusing element used and the respective process procedure. The most important industrial heat treatment process is case-hardening, which consists of thermochemical diffusion process carburising or its variation carbonitriding, followed by a subsequent quench. The latest developments of using different gaseous carburising agents and increasing the carburising temperature are one main area of this *** other area is the evolvement of nitriding and especially the ferritic nitrocarburising process by improved process control and newly developed process variations using carbon, nitrogen and oxygen as diffusing elements in various process steps. Also boronizing and special thermo-chemical processes for stainless steels are discussed.

关键词：热化学扩散高温渗碳渗氮位控制溶体渗氮

Probiotics in shellfish aquaculture

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Aquaculture and Fisheries 2020年第1期5卷 1-27页

作者： Einar ringΦ Norwegian College of Fishery Science Faculty of BiosciencesFisheries and EconomicsUiTThe Arctic University of NorwayTromso 9037Norway A R

The shellfish aquaculture industry has dramatically developed during the last two ***,this de-velopment has,in some cases,resulted in environmental degradation,emergence of diseases and low *** need for improving disease resistance,growth performance,feed efficiency,and safe aquatic production for human consumption has stimulated development and applications of probiotics in *** used in shellfish aquaculture include genera of Lactobacillus,Enterococcus,Bacillus,Aeromonas,Alteromonas,Arthrobacter,Bifidobacterium,Clostridium,Parnibaillus,Phaeobacter,Pseudoalteromonas,Pseudomonas,Rhodosporidium,Roseobacter,Streptomyces and *** beneficial effects of these probiotics include improved growth performance,enzymatic contribution to nutrition,inhibition of adherence and colo-nization of pathogenic bacteria in the digestive tract,modulation of the gut microbiota,and increase haema-tological parameters and immune *** present review addressed insight into the application of probiotics in shellfish aquaculture,methods of administration,mode of actions,and their enhancing effects,and discuss research gaps and issues that merit further investigations.

关键词： Probiotics Shellfish Aquaculture

Effects of temperature and sodium carboxylate additives on mineralization of calcium oxalate in silica gel systems

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Science China Chemistry 2004年第4期47卷 311-319页

作者： bernd Tieke Institut fur Physikalische Chemie Universitt zu Kln Luxemburgerstr. 116 D-50939 Kln Germany

The effects of temperature and multifunctional sodium carboxylate additives on the phase composition and morphology of calcium oxalate (CaOxa) crystals grown in silica gel system were systematically investigated using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and Fourier-transform infrared spectra (FT-IR). The sodium carboxylates investigated include: monocarboxylate sodium acetate (NaAc), disodium tartrate (Na2tart), trisodium citrate (Na3cit), and the disodium salt of ethylenediaminetetraacetic acid (Na2edta). The temperature range was from 7°C to 67°C. The crystallization temperature affects the phase compositions, the growth rate, and the morphology of CaOxa. First, the logarithm of the percentage of calcium oxalate dihydrate (COD) formed at a certain temperature (T) is proportional to the reciprocal of temperature (1/T). Second, the weight of CaOxa crystals decreases as decreasing the temperature. At a given temperature, the ability of the sodium carboxylates to induce COD follows the order: Na2edta Na3cit Na2tart NaAc. Third, the multicarboxylates can decrease the surface area of calcium oxalate monohydrate (COM). It makes the edges and tips of COM crystals blunt and oval. All the three changes, an increase of the content of COD, a decrease of the weight of CaOxa crystals, and a decrease of the surface area of COM crystals, can inhibit the formation of CaOxa stones. These results support the clinical use of citrates and may be helpful in elucidating the mechanisms of the formation of CaOxa calculus. Keywords calcium oxalate - sodium carboxylate - gel - urinary calculi - crystallization - biomineralization

关键词： calcium oxalate sodium carboxylate gel urinary calculi crystallization biomineralization

Improvement,validation and application of CFD/DEM model to dense gas-solid flow in a fluidized bed

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Particuology 2013年第5期11卷 514-526页

作者： Falah Alobaid bernd Epple TU Darmstadt Energiesysteme und EnergietechnikPetersenstrasse 3064287 DarmstadtGermany

Dense gas-solid flow with solid volume fraction greater than 10% and at moderate Reynolds number is important in many industrial facilities such as fluidized beds. In this work, the Euler-Lagrange approach in combination with a deterministic collision model is applied to a laboratory-scale fluidized bed. The fluid-particle interaction is studied using a new procedure called the offset method, which results in several numbers of spatial displacements of the fluid grid. The proposed method is highly precise in determining porosity and momentum transfer, thus improving simutation accuracy. A validation study was carried out to assess the results using this in-house CFD/DEM code against 5-s operation of a Plex- iglas spouted-fluidized bed, showing good qualitative correlation of solid distribution in the bed and acceptable quantitative agreement of pressure drops at different positions in the bed. In view of high computing cost, special emphasis is placed on effective program design, such as application of advanced detection algorithm for particle-particle/wall collisions, the multi-grid method and parallel calculation. In this context, the influence of increasing the processor number, up to 36, on calculation efficiency was investigated.

关键词： Dense gas-solid flowComputational fluid dynamicsDiscrete element methodOffset methodParallelisation

Ferrimagnetic ceramic adsorbents for cleanup of H_2S from exhaust gases

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China Particuology 2007年第1期5卷 156-161页

作者： bernd Halbedel Apostolos Kontogeorgakos Institute of Materials Science Glass and Ceramic Technology Group Technische Universitt Ilmenau P.O. Box 10 05 65 D-98684 Ilmenau Germany NCSR "Demokritos" Institute of Materials Science 15310 Aghia Paraskevi Attiki Greece

Adsorbents that exhibit magnetic properties in addition to other required process-relevant characteristics open up new perspectives for the dry reduction and/or elimination of HES and other sulfur compounds from exhaust gases. These adsorbents eliminate the sulfur compounds from exhaust gases by virtue of their coatings and their magnetic property which makes it possible the use of magnetically assisted and stabilized fluidization in an externally applied magnetic field. In the present paper, the feasibility of the sorptive function of porous ceramic ferrimagnetic beads is ensured by sol-gel coating of zinc oxide without the formation of Zn-Fe-oxides and without considerable decrease of available pore volume. The results of material characterization by SEM, Auger electron spectroscopy, X-ray and mercury-porosity measurements and the loading capacity of a HES/N2 model gas are presented and discussed. The resulting HES loading of the functionalized adsorbent beads is more than 10 times larger than that of the starting material. @ 2007 Chinese Society of Particuolo^v and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V.

关键词： Adsorption Adsorbents Ferrites Magnetic materials Magnetic properties Sol-gel Zinc oxide

g factors of nuclear low-lying states:A covariant description

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Science China(Physics,Mechanics & Astronomy) 2011年第2期54卷 198-203页

作者： YAO JiangMing PENG Jing MENG Jie ring Peter School of Physical Science and Technology Southwest University Chongqing 400715 China Department of Physics Beijing Normal University Beijing 100875 China State Key Laboratory for Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China Department of Physics University of Stellenbosch Stellenbosh South Africa Physik-Department der Technischen Universitat Munchen D-85748 Garching Germany

The g factors and spectroscopic quadrupole moments of low-lying excited states 2+1,…,81+ in 24Mg are studied in a covariant density functional *** wave functions are constructed by configuration mixing of axially deformed mean-field states projected on good angular *** mean-field states are obtained from the constraint relativistic point-coupling model plus BCS calculations using the PC-F1 parametrization for the particle-hole channel and a density-independent delta-force for the particle-particle *** available experimental g factor and spectroscopic quadrupole moment of 21+ state are reproduced quite *** angular momentum dependence of g factors and spectroscopic quadrupole moments,as well as the effects of pairing correlations are investigated.

关键词： covariant density functional theory magnetic moment g factor spectroscopic quadrupole moment