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Forming Process of Strong Anisotropic Material Based on the Hydrodynamic Deep Drawing with Radial Pressure

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Journal of Materials Science & Technology 2005年第5期21卷 733-737页

作者： joachim DANCKERT Karl Brian NIELSEN Department of Production Aalborg University Fibigerstraede 16 DK-9220Aalborg DenmarkDepartment of ProductionAalborg University Fibigerstraede 16 DK-9220Aalborg Denmark

The hydrodynamic deep drawing process enables net shape or near net shape forming of complicated sheet metal parts made from difficultly forming materials, such as aluminium or high strength steels. Based on the conventional hydrodynamic deep drawing process, a new process, hydrodynamic deep drawing process, in which radial pressure is applied to the rim of the blank, is proposed. This new process has been analysed using FEM simulations and the obtained results have been compared with the experimental results. The material used in the experiments was Al-Mg-Si alloy, and in the FEM-simulations the elastic-plastic behaviour of Al-Mg-Si alloy was modelled using Barlat＇s 89 yield criteria.

关键词： Hydroforming Hydrodynamic deep draw Simulation Aluminum alloy

Metamorphic Evolution of Chloritoid-Bearing Micaschist from the Variscan Elstergebirge: Evidences for Stacking of High-Pressure Rocks in the Saxothuringian Zone of Central Europe

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Journal of Earth Science 2020年第3期31卷 425-446页

作者： Gelareh Rahimi Hans-joachim Massonne Fakultat Chemie Universitat Stuttgart70569 StuttgartGermany School of Earth Sciences China University of GeosciencesWuhan 430074China

A chloritoid-garnet-bearing micaschist from the southern part of the Elstergebirge was studied to better understand the Variscan orogenic evolution in the Saxothuringian zone of the northwestern Bohemian *** on the textural relations and compositions of minerals,especially of zoned garnet and potassic white mica,a P-T path was reconstructed using contoured P-T *** U-Th-Pb dating of monazite in the micaschist was undertaken with the electron *** micaschist experienced P-T conditions along a clockwise path between 16 kbar at 510℃and 5 kbar at 555℃followed by isobaric heating to about 600℃.Monazite ages range between 315 and 480 Ma with the most prominent maxima and side maxima at 346.0±1.1(2σ),357.3±2.3,and 368.3±1.7 *** older than 380 Ma were related to detrital monazite pointing to a Devonian sedimentary *** ages around 325 Ma were assigned to the isobaric heating by nearby post-tectonic *** high-pressure event,being the result of the collision of Laurussia and Gondwana after closure of the Rheic Ocean,occurred in the Late *** exhumation to 15-20 km(5 kbar)ended probably in the Early *** high-pressure micaschists from the Fichtelgebirge to the Erzgebirge crystalline complexes are suggested to represent a single nappe within a metamorphic nappe *** nappe is composed of metasedimentary slices,which experienced different peak pressures rather than representing a coherent crustal section.

关键词： Saxothuringian micaschist chloritoid garnet monazite dating Variscan P-T path

A revision of Gynura (Asteraceae: Senecioneae)

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Journal of Systematics and Evolution 2011年第4期49卷 285-314页

作者： Ongkarn VANIJAJIVA joachim W.KADEREIT Institute for Special Botany and Botanical Garden Johannes Gutenberg University Faculty of Science and Technology Phranakhon Rajabhat University

A revision of the paleotropical genus Gynura *** ***-four species are recognized,of which three are described as *** are *** Vanijajiva & Kadereit,*** Vanijajiva & Kadereit,and *** Vanijajiva & *** dissecta (***) Vanijajiva & Kadereit,*** (***) Vanijajiva & Kadereit,and *** (Bl.) *** (***) Vanijajiva & Kadereit are new *** identification key,descriptions,and distribution maps are provided.

关键词： Compositae Gynura Gynuroid group revision taxonomy.

Associations between diagnosis with stroke,comorbidities,and activity of daily living among older adults in the United States

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Chronic Diseases and Translational Medicine 2023年第2期9卷 164-176页

作者： Suebsarn Ruksakulpiwat Wendie Zhou Lalipat Phianhasin Chitchanok Benjasirisan Saeideh Salehizadeh Limin Wang joachim G.Voss Department of Medical Nursing Faculty of NursingMahidol UniversityBangkokThailand School of Nursing Peking UniversityBeijingChina University Hospitals Cleveland Medical Center ClevelandOhioUSA School of Nursing Zhejiang Chinese Medical UniversityZhejiangChina Frances Payne Bolton School of Nursing Case Western Reserve UniversityClevelandOhioUSA

Background:Stroke is the leading cause of *** study aimed to investigate the association between stroke,comorbidities,and activity of daily living(ADL)among older adults in the United ***:Participants were 1165 older adults aged 60 and older from two waves(2016 and 2018)of the Health and Retirement Study who had a *** statistics were used to describe demographic information and *** regressions and multiple regression analyses were used to determine associations between stroke,comorbidities,and ***:The mean age was 75.32±9.5 years,and 55.6%were *** adjusted analysis shows that older stroke adults living with diabetes as comorbidity are significantly associated with difficulty in dressing,walking,bedding,and ***,depression was significantly associated with difficulty in dressing,walking,bathing,eating,and *** the same time,heart conditions and hypertension as comorbidity were rarely associated with difficulty in *** adjusting for age and sex,heart condition and depression are significantly associated with seeing a doctor for stroke(odds ratio[OR]:0.66;95%confidence interval[CI]:0.49-0.91;p=0.01)and stroke therapy(OR:0.46;95%CI:0.25-0.84;p=0.01).Finally,stroke problem(unstandardizedβ[B]=0.58,p=0.017)and stroke therapy(B=1.42,p<0.001)significantly predict a lower level of ***:This study could benefit healthcare professionals in developing further interventions to improve older stroke adults'lives,especially those with a high level of dependence.

关键词： activity of daily living comorbidity older adults stroke

Tree water potentials supporting an explanation for the occurrence of Vachellia erioloba in the Namib Desert (Namibia)

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Forest Ecosystems 2017年第4期4卷 303-312页

作者： joachim H. A. Krug Institute for Silviculture and Forest Ecology Georg-August-University of Gottingen Bosgenweg 1 37077 Gottingen Germany

Background： Site-vegetation relations of Vachellia erioloba, Faidherbia albido, Euclea pseudebenus and Tamarix usneoides in two contrasting locations in the Namib Desert （Namibia） were evaluated with the goal to relate soil water availability to the occurrence of trees under hyper-arid conditions, Methods： Plant water potentials were measured using a pressure chamber in the field. Pre-dawn water potentials were assessed to reflect the soil water potential of the rhizosphere. Midday water potentials were measured to assess the strongest negative water potential applied by the sample trees. Results： Pre-dawn water potentials and midday water potentials indicated access to soil water in the rhizosphere and by this, provide an explanation for an occurrence of V. erioloba within the extreme environmental conditions of sand dunes in the Namib Desert. Diurnal ranges seem to reflect more and less suitable stands, in terms of soil water availability, within the sampling sites. While the impact of the ephemeral Kuiseb river on soil water availability was assessed through the four species＇ plant-internal water relations, comparable pre-dawn water potentials of V. erioioba at both sites indicate soil water availability also in the dunes of Namibrand. The extreme midday water potentials of the dune plants possibly show the upper limit of tolerance for V. eriolobo. Conclusions： The preliminary data provide an explanation of the occurrence and distribution of the investigated species in beds of ephemeral rivers and on dunes under the hyper-arid climatic conditions of the Namib Desert and qualify suitability within the assessed sites. Understanding the plant-physiological processes and assessing the plant-internal water potential provides a valuable tool to evaluate soil water availability within the rhizosphere and to describe an adaptation potential of investigated species. The comparability of pre-dawn water potentials at both sites indicates unexpected soil water availability w

关键词： Water potential Arid land Soil water availability Namibia V. erioloba

Improvement of the Corrosion Resistance of High Alloyed Austenitic Cr-Ni-Mo Stainless Steels by Solution Nitriding

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材料热处理学报 2004年第5期25卷 316-321页

作者： Christine Eckstein Heinz- joachim Spies Jochen Albrecht Dept. of Materials Eng. Technische Universitat Bergakademie Freiberg 09599 Freiberg/GermanyDept. of Materials Eng. Technische Universitat Bergakademie Freiberg 09599 Freiberg/GermanyInstitut Fresenius GmbH Solid State Analytic Zur Wetterwarte 10Haus 107 01109 Dresden Germany

Characteristic features of austenitic steel grades combine a good corrosion resistance with a low hardness, wear resistance and scratch resistance. An interesting possibility for improving the wear behaviour of these steels without loss of their corrosion resistance lies in enriching the near surface region with nitrogen. The process of a solution nitriding allows the rise of the solution of nitrogen in the solid phase. On this state nitrogen increases the corrosion resistance and the tribilogical load-bearing capacity. The aim of the study was, to investigate the improvement of the pitting corrosion behaviour by solution nitriding. A special topic was to observe the effect of nitrogen by different molybdenum content. So austenitic stainless steels (18% Cr, 12% Ni, Mo gradation between 0.06 to 3.6%) had been solution nitrided. The samples could be prepared with various surface content of nitrogen from 0.04 to 0.45% with a step-by-step grinding. The susceptibility against pitting corrosion of these samples had been tested by determination of the stable pitting potential in 0.5M and 1M NaCl at 25°C. For the investigated steel composition and the used corrosion system there is no influence of molybdenum on the effectiveness of nitrogen. The influence of nitrogen to all of the determined parameters can be described well by PRE = Cr + 3,3 * Mo + 25 *N. XPS analysis of the sample surfaces support the results of the pitting corrosion *** surface investigations with an acid elektolyte (0,1M HC1 + 0,4M NaCl) were performed. In this case the passivation effective nitrogen content increases markedly with rising molybdenum concentration of the steel. Obviously an interaction of Mo and N is connected with a strongly acid electrolyte.

关键词：耐蚀性奥氏体不锈钢 Cr-Ni-Mo 渗氮 PRE 稳定点蚀电位

Utilizing melt crystallization fundamentals in the development of a new tabletting technology

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Frontiers of Chemical Science and Engineering 2014年第3期8卷 346-352页

作者： Ahmed ABOUZEID Sandra PETERSEN joachim ULRICH Martin Luther University Halle-Wittenberg Center for Engineering Science Thermal Process Engineering D-06099 Halle Germany

Increasing production effeciency and lowering costs are some of the many advantages melt crystallization technology offers over the conventional methodology of tabletting. A normal tablet consists of a pure shell or a coat and a separate core constituting the pharmaceutical active ingredient. Great emphasis is put on the purity of the shell since its purpose is to solely protect and deliver the active ingredient to its target. Melt crystallization is a purification （separation） process. It is discussed here for its ability to produce coated tablets, by separating the ＂coating＂ material from the ＂to be coated＂ material coming from one molten mixture. Molten drops of lutrol-ibuprofen mixture are produced using the drop forming technique. The subsequent analysis involves proving and quantifying the phase separation （coat purity）. The mechanism of a crystallizing drop is shown as direct evidence of the ongoing process. Moreover, solidified tablet batches are analyzed for the purity of their coating by measuring the ibuprofen concentration. This optimization process is carried out through multiple stages of development and condition enhancements in order to produce the most pure tablet coating. As a result, a trial showing an almost purely coated tablet is presented here.

关键词： phase separation melt crystallization tablets,process optimization

The inducible nitric oxide synthaseinhibitor 1400W as a potential treatment for retinal diseases

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Neural Regeneration Research 2021年第6期16卷 1221-1222页

作者： Sven Schnichels Stephanie C.joachim University Eye Hospital Tübingen Centre for OphthalmologyTübingenGermany Experimental Eye Research Institute University Eye HospitalRuhr-University BochumBochumGermany

The overproduction of reactive oxygen species is defined as oxidative *** deprived oxygen supply in tissues is known as *** mechanisms contribute to the pathogenesis of several retinal diseases,like glaucoma,age-related macular degeneration(AMD),and retinal *** is a neurodegenerative disease defined by a progressive loss of retinal ganglion cells(RGCs)and their axons causing visual field defects,which ultimately leads to *** AMD pathogenesis is further characterized by soft drusen,it involves the retinal pigment epithelium and the Bruch’s membrane-choroid complex.

关键词： AMD diseases potential

Predicting Arabidopsis Freezing Tolerance and Heterosis in Freezing Tolerance from Metabolite Composition

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Molecular Plant 2010年第1期3卷 224-235页

作者： Marina Korn Tanja Gaetner Alexander Erban joachim Kopka joachim Selbig Dirk K. Hincha Max-Planck-lnstitut fur Molekulare Pflanzenphysiologie Am Muhlenberg 1 D-14476 Potsdam Germany Abteilung Bioinformatik Institut for Biochemie und Biologie Universit~t Potsdam Karl-Liebknecht-Str. 24-25 D-14476 Potsdam Germany

Heterosis, or hybrid vigor, is one of the most important tools in plant breeding and has previously been dem- onstrated for plant freezing tolerance. Freezing tolerance is an important trait because it can limit the geographical dis- tribution of plants and their agricultural yield. Plants from temperate climates increase in freezing tolerance during exposure to low, non-freezing temperatures in a process termed ＇cold acclimation＇. Metabolite profiling has indicated a major reprogramming of plant metabolism in the cold, but it has remained unclear in previous studies which of these changes are related to freezing tolerance. In the present study, we have used metabolic profiling to discover combinations of metabolites that predict freezing tolerance and its heterosis in Arabidopsis thaliana. We identified compatible solutes and, in particular, the pathway leading to raffinose as crucial statistical predictors for freezing tolerance and its heterosis, while some TCA cycle intermediates contribute only to predicting the heterotic phenotype. This indicates coordinate links between heterosis and metabolic pathways, suggesting that a limited number of regulatory genes may determine the extent of heterosis in this complex trait. In addition, several unidentified metabolites strongly contributed to the prediction of both freezing tolerance and its heterosis and we present an exemplary analysis of one of these, identifying it as a hexose conjugate.

关键词： Abiotic/environmental stress cold acclimation metabolomics bioinformatics biostatistics Arabidopsis.