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Lab experiments on the innovative rapid thick strip casting process

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 391-398页

作者： Richard Nagy dieter Senk Department of Ferrous Metallurgy IEHK RWTH Aachen UniversityAachen 52056Germany

Rapid thick strip casting （RTSC） by Anton Hulek, Inventmetall, is an innovative concept for the production of hot strips with a final as-cast thickness of about 25 mm before rolling. The innovation of the mechanism consists in a vertical mould performing a caterpillar motion. This moving mould has an unconventional parallelogram-shaped cross-section. The conventional rectangular shape is formed in the shaping machine, which is placed straight below the mould. Further elements of the technology are state-of-the-art. For the investigation of this new casting system theoretical calculations were complemented with practical experiments. The investigation focused mainly on two key aspects： the characteristics of the mould and the shaping process. For the practical analysis a static mould with three pairs of elements in laboratory scale was developed and commissioned by the Dept. of Ferrous Metallurgy @ RWTH Aachen University. The shaping experiments were carried out in model scale with two different materials and in variable boundary conditions. The results of these experiments delivered important mechanical as well as thermal informations about the casting system.

关键词： continuous casting rapid solidification strip metal moulds near-net-shape casting

PET imaging in ischemic cerebrovascular disease:current status and future directions

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Neuroscience Bulletin 2014年第5期30卷 713-732页

作者： Wolf-dieter Heiss Max Planck Institute for Neurological Research

Cerebrovascular diseases are caused by interruption or significant impairment of the blood supply to the brain, which leads to a cascade of metabolic and molecular alterations resulting in functional disturbance and morphological damage. These pathophysiological changes can be assessed by positron emission tomography （PET）, which permits the regional measurement of physiological parameters and imaging of the distribution of molecular markers. PET has broadened our understanding of the flow and metabolic thresholds critical for the maintenance of brain function and morphology： in this application, PET has been essential in the transfer of the concept of the penumbra （tissue with perfusion below the functional threshold but above the threshold for the preservation of morphology） to clinical stroke and thereby has had great impact on developing treatment strategies. Radioligands for receptors can be used as early markers of irreversible neuronal damage and thereby can predict the size of the final infarcts; this is also important for decisions concerning invasive therapy in large （＂malignant＂） infarctions. With PET investigations, the reserve capacity of blood supply to the brain can be tested in obstructive arteriosclerosis of the supplying arteries, and this again is essential for planning interventions. The effect of a stroke on the surrounding and contralateral primarily unaffected tissue can be investigated, and these results help to understand the symptoms caused by disturbances in functional networks. Chronic cerebrovascular disease causes vascular cognitive disorders, including vascular dementia. PET permits the detection of the metabolic disturbances responsible for cognitive impairment and dementia, and can differentiate vascular dementia from degenerative diseases. It may also help to understand the importance of neuroinflammation after stroke and its interaction with amyloid deposition in the development of dementia. Although the clinical application of PET

关键词： stroke dementia PET brain metabolism brain ischemia

Natural water purification and water management by artificial groundwater recharge

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第3期9卷 221-226页

作者： Klaus-dieter BALKE Institute for Geosciences University of TübingenSigwartstr.10D-72076 TübingenGermany

Worldwide,several regions suffer from water scarcity and *** infiltration and subsurface storage of rain and river water can reduce water *** groundwater recharge,possibly combined with bank filtration,plant purification and/or the use of subsurface dams and artificial aquifers,is especially advantageous in areas where layers of gravel and sand exist below the earth's *** infiltration of surface water into the uppermost aquifer has qualitative and quantitative *** contamination of infiltrated river water will be reduced by natural *** minerals,iron hydroxide and humic matter as well as microorganisms located in the subsurface have high decontamination *** this,a final water treatment,if necessary,becomes much easier and *** quantitative effect concerns the seasonally changing river discharge that influences the possibility of water extraction for drinking water *** changes can be equalised by seasonally adapted infiltration/extraction of water in/out of the aquifer according to the river discharge and the water *** method enables a continuous water supply over the whole ***,artificially recharged groundwater is better protected against pollution than surface water,and the delimitation of water protection zones makes it even more save.

关键词： Artificial groundwater recharge Natural attenuation Water management

Recent advances in hepatitis B virus research:A German point of view

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World Journal of Gastroenterology 2007年第1期13卷 8-13页

作者： dieter Glebe Institute of Medical Virology Justus-Liebig University of Giessen Giessen Germany

More than 30 years after the discovery of human hepatitis B virus （HBV） this virus remains to be one of the major global health problems. In infected adolescents or adults, 5%-10% will lead to a chronic carrier state, whereas in infected neonates up to 90% develop chronicity. It is estimated that about 370 million people are chronic carriers of HBV worldwide. In many regions of the world, chronic HBV infection is still the major cause of liver cirrhosis and hepatocellular carcinoma. During the last 30 years, many steps of the viral life cycle have been unravelled, mainly due to cloning, sequencing and expression of the genomic DNA extracted from HBV virions. This has lead to the development of a safe and efficient vaccine and sensitive tests for HBV surface prol^in （HBsAg） allowing reliable diagnosis and screening of blood products. More recently, a growing number of reverse transcriptase inhibitors have been developed. However, together with these improvements new defidencies in prevention and cure of HBV infections are becoming apparent. Although HBV is a DNA virus, it is highly variable under immunity or drug induced selection pressure, resulting in vaccine-related escape mutants and drug resistance. To overcome these challenging problems new antivirals and optimised vaccines have to be developed.

关键词： Hepatitis B virus Molecular biology Viral life cycle Animal system Antiviral therapy

Eigenvalue sensitivity analysis based on the transfer matrix method

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International Journal of Mechanical System Dynamics 2021年第1期1卷 96-107页

作者： dieter Bestle Engineering Mechanics and Vehicle Dynamics Brandenburg University of Technology Cottbus‐SenftenbergCottbusGermany

For linear mechanical systems,the transfer matrix method is one of the most efficient modeling and analysis ***,in contrast to classical mod-eling strategies,the final eigenvalue problem is based on a matrix which is a highly nonlinear function of the ***,classical strategies for sensitivity analysis of eigenvalues *** parameters cannot be *** paper develops two specific strategies for this situation,a direct differentiation strategy and an adjoint variable method,where especially the latter is easy to use and applicable to arbitrarily complex chain or branched multibody *** the system analysis itself,it is able to break down the sensitivity analysis of the overall system to analytically determinable derivatives of element transfer matrices and recursive formula which can be applied along the transfer path of the topology *** examples of different complexity validate the proposed approach by comparing results to analytical calculations and numerical *** obtained procedure may support gradient‐based optimization and robust design by delivering exact sensitivities.

关键词： adjoint variable method direct differentiation sensitivity analysis transfer matrix method

Groundwater protection:What can we learn from Germany?

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第3期9卷 227-231页

作者： Klaus-dieter BALKE Institute for Geosciences University of TübingenSigwartstr.10D-72076 TübingenGermany

For drinking water security the German waterworks proceed on a comprehensive concept,i.e.,the protection of all the regions from the recharge area to the *** includes the protection of the recharge area by a precautionary management,a safe water treatment,a strict maintenance of the water distribution network,continuous control and an intensive training of *** protection zones together with effective regulations and control play a very important *** protection zones with different restrictions in land-use are *** in reservoirs and lakes is also protected by Surface Water Protection *** the surrounding area the land-use is controlled,*** treatment is necessary if acidification happens caused by acid rain,or eutrophication caused by the inflow of *** important is the collaboration between waterworks and the farmers cultivating land in the recharge area in order to execute water-protecting ecological farming with the aim to reduce the application of fertilizers and plant protection *** financial losses have to be compensated by the waterworks.

关键词： Drinking water security Germany Groundwater protection zone Water protection

Investigation of the steam-cooled blade in a steam turbine cascade

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航空动力学报 2007年第5期22卷 673-682页

作者： dieter Bohn Jing Ren Karsten Kusterer Institute of Steam and Gas Turbines RWTH Aachen UniversityTemplergraben 55 D-52056 Aachen Germany B＆B-AGEMA Gesellschaft far Energietechnische Maschinenund Anlage GmbH Jülicher Strasse 338 52070 Aachen Germany

With the increasing demand for electricity,an efficiency improvement and thereby reduced CO2 emissions of the coal-fired plants are expected in order to reach the goals set in the Kyoto *** can be achieved by a rise of the process ***,live steam pressures and temperatures up to 300 bars and 923 K are planned as the next *** circuit steam cooling of blades and vanes in modern steam turbines is a promising technology in order to establish elevated live steam temperatures in future steam turbine *** this paper,a steam-cooled test vane in a cascade with external hot steam flow is analyzed numerically with the in-house code CHTflow.A parametric analysis aiming to improve the cooling effectiveness is carried out by varying the cooling mass flow *** results from two investigated cases show that the steam cooling technique has a good application potential in the steam *** internal part of the vane is cooled homogeneously in both *** the increased cooling mass flow rate,there is a significant improvement of cooling efficiency at the leading *** results show that the increased cooling mass flow ratio can enhance the cooling effectiveness at the leading *** respect to trailing edge,there is no observable improvement of cooling effectiveness with the increased cooling mass *** implies that due to the limited dimension at the trailing edge,the thermal stress cannot be decreased by increasing the cooling mass flow ***,impingement-cooling configuration at the trailing edge might be a solution to overcome the critical thermal stress *** is also observed that the performance of the cooling effective differs on pressure side and suction *** implicates that the equilibrium of the cooling effectiveness on two sides are influenced by a coupled relationship between cooling mass flow ratio and hole *** future work,optimizing the hole geometry and cooling steam supply conditions might b

关键词：蒸汽轮机层叠蒸汽冷却调查研究翼热转移

Critical role of butyrophilin 3A1 in presenting preny pyrophosphate antigens to human y~ T cells

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Cellular & Molecular Immunology 2014年第2期11卷 117-119页

作者： dieter Kabelitz Institute of Immunology University of Kiel Kiel Germany

Tlymphocytes recognize antigen via the heterodimeric T-cell receptor（TCR） which is closely associated with the signal-transducing CD3 complex. αβ TCR-expressing T cells recognize peptides presented by MHC class II （for CD4＋ T cells） or MHC class I molecules （for CD8＋ T cells）. In striking contrast, the majority of human y8 T cells expres- sing the Vy9V82-encoded TCR recog- nize small non-peptidic phosphorylated ligands which have been identified as pyrophosphate intermediates of micro- bial and eukaryotic isoprenoid synthesis.

关键词： T细胞受体抗原焦磷酸脂蛋白人类细胞识别异源二聚体 T淋巴细胞

Multilayer epigenetic analysis reveals novel transcription factor networks in CD8 T cells

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Cellular & Molecular Immunology 2018年第3期15卷 199-202页

作者： Jaydeep Bhat dieter Kabelitz Institute of Immunology University of KielKielD-24105Germany

A characteristic feature of the adaptive immune system is immunological memory,which is the more rapid and more potent response to antigenic challenge upon re-encountering the antigen–even years after the primary antigen ***8 T cells are essential players in the adaptive immune response to viruses and intracellular *** infection,antigen-responsive naive CD8 T cells are activated and they clonally expand to give rise to sufficient effector cell numbers to execute an adequate immune *** cells are deleted after the clearance of infection,but some T cells survive and are maintained as memory T cells in a non-proliferative state in secondary lymphoid tissues and bone marrow.1 Complex transcriptional programs regulate CD8 T-cell differentiation from antigen-inexperienced naive cells via the effector cell stage towards long-term memory cells.

关键词： infection maintained networks