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International Journal of Geosciences 2014年第11期5卷 1383-1394页

作者： Carolina Doranti-Tiritan peter christian hackspacher Daniel Henrique de Souza Marli Carina Siqueira-Ribeiro Instituto de Geociências e Ciências Exatas UNESP Rio Claro Brazil

The Pocos de Caldas Plateau is formed by the alkaline intrusion of Pocos de Caldas and surrounding metamorphic basement. It is characterized as a remnant of the South American Planation Surface resulted from erosional events from Late Cretaceous-Paleogene transition. Pocos de Caldas Alkaline Massif (PCAM) was formed during alkaline volcanism event from the Late Cretaceous. It is located on the west side of the Mantiqueira Mountain Range, characterized by alkaline rocks and topography reaches over 1700 m high. A major feature of denudation is the development of the “circular drainage”, a particular feature of some caldera and other circular or concentric structural features. Recent tectonic movements may critically affect regional geomorphology by influencing river patterns and orientations. The morphometric analysis shows that some rivers are controlled by reactivated faults, however, in some regions the lithology has major influence in the rivers development.

关键词： Component Formatting Style Styling Insert

Determination of riding comfort on cycleways using a smartphone application

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 747-760页

作者： Anna Niska Leif Sjögren peter Andrén christian Weber Tineke de Jong Aslak Fyhri Department of Infrastructure Maintenance Swedish National Road and Transport Research Institute(VTI)Linköping SE-58195Sweden Department of Safety and Behavior Institute of Transport EconomicsGaustadalleen 210349 OsloNorway

Well maintained cycleways will encourage more people to cycle,as the condition of cycleways is important for the safety,accessibility and riding comfort of *** that,only a few models used to describe the quality of service for cyclists take the surface condition into *** measuring methods are needed to enable reliable and effective assessment of surface conditions,and measurable performance criteria related to the needs of cyclists should be *** purpose of this study has been to test the reliability and validity of using accelerometers in smartphones to assess the riding comfort on cycleways.A smartphone application converting three-dimensional accelerometer measurements into a single indicator for cycleways has been used to assess road surfaces in two field studies,in Sweden and Norway,*** studies assessed test sections of varying *** relate the measurements to subjective riding comfort assessments by cyclists,recruited cyclists collected quantitative data using the app,whilst also rating their perceived riding comfort by completing a *** were also related to standard road surface condition indicators,generated from a road surface tester equipped with 19 laser sensors:international roughness index(IRI),mega-and *** results show that it is possible to describe the unevenness of a cycleway using the technology present in smartphones.A software application can be used to collect and analyse data from the acceleration sensors in the phone,which can then be used to describe the riding comfort of *** is mainly the unevenness in the 50-1000 mm sizerange that create the greatest discomfort for cyclists,and intermittent vibrations are perceived as more uncomfortable than more evenly distributed ***,IRI is not a relevant measurement for describing the riding comfort of cyclists.

关键词： Cyclist Comfort Assessment Road surface measurement Smartphone application

Wear-resistant CoCrNi multi-principal element alloy at cryogenic temperature

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Science Bulletin 2024年第2期69卷 227-236页

作者： Yue Ren Qing Zhou Dongpeng Hua Zhuobin Huang Yulong Li Qian Jia peter Gumbsch christian Greiner Haifeng Wang Weimin Liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Institute for Applied Materials Karlsruhe Institute of TechnologyKarlsruhe 76131Germany IAM-ZM MicroTribology CenterμTC Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Fraunhofer IWM Freiburg 79108Germany State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic ***,we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K,surpassing those of cryogenic austenitic *** temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic *** is found that sliding-induced subsurface structures show distinct scenarios at different deformation *** cryogenic condition,significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface,which can accommodate massive sliding deformation,in direct contrast to the strain localization and delamination at 273 ***,the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation)also provide additional strengthening and toughening of the subsurface *** features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

关键词： Multi-principal element alloy Cryogenic temperature Wear CoCrNi

Ray tracing particle image velocimetry-Challenges in the application to a packed bed

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Particuology 2024年第1期84卷 194-208页

作者： Christin Velten Mirko Ebert christian Lessig Katharina Zahringer Lehrstuhl für Strömungsmechanik und Strömungstechnik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany Institut für Simulation und Graphik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany

Ray tracing Particle Image Velocimetry(RT-PIV)is an optical technique for high resolution velocity measurements in challenging optical systems,such as transparent packed beds,that uses ray tracing to correct for distortions introduced by transparent geometries in the light *** ray tracing based correction is a post processing step applied to the raw PIV particle images before classical PIV *** this study,RT-PIV is performed in the top layer of a body centred cubic(bcc)sphere packing with gaseous flow,where optical access is obtained by the use of transparent N-BK7 glass balls with a diameter of d=40 ***-PIV introduces new experimental and numerical challenges,for example a limited field of view,illumination difficulties,a very large required depth of field and high sensitivity to geometric parameters used in the ray tracing *** challenges and their implications are the main scope and discussed in the present ***,the validation of the ray tracing reconstruction step is presented and examples for the obtained corrected vector fields in a packed bed are *** results show the strength of the method in reconstructing velocity fields behind transparent spheres that would not have been accessible by optical measurement techniques without the ray tracing correction.

关键词： Ray tracing particle image velocimetry(RT-PIV) Transparent spherical particles Packed bed Distortion correction Gas flow

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低温耐磨的CoCrNi多主元合金（英文）

Science Bulletin 2024年第2期 227-236页

作者：任越周青华东鹏黄卓斌李钰龙贾茜 peter Gumbsch christian Greiner 王海丰刘维民 State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University Institute for Applied Materials Karlsruhe Institute of Technology IAM-ZM Micro Tribology Center μTC Karlsruhe Institute of Technology Fraunhofer IWM State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic temperature. Here, we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K, surpassing those of cryogenic austenitic steels. The temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic simulation. It is found that sliding-induced subsurface structures show distinct scenarios at different deformation temperatures. At cryogenic condition, significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface, which can accommodate massive sliding deformation, in direct contrast to the strain localization and delamination at 273 ***, the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation) also provide additional strengthening and toughening of the subsurface material. These features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

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TABS: Transforming automatically BPMN models into blockchain smart contracts

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Blockchain(Research and Applications) 2023年第1期4卷 90-115页

作者： peter Bodorik christian Gang Liu Dawn Jutla Faculty of Computer Science Dalhousie UniversityHalifaxNS B3H 4R2Canada Sobey School of Business Saint Mary's UniversityHalifaxNS B3H 3C3Canada

Research on blockchains addresses multiple issues,with one being the automated creation of smart *** smart contract methods is more difficult than mainstream software development as the underlying blockchain infrastructure poses additional *** report on a new approach to developing smart contracts with the objective of automating the process to increase developer efficiency and reduce the risk of errors introduced by software *** support industry adoption,we use Business Process Model and Notation(BPMN)modeling to describe an application while targeting applications in the trade *** describe a system that transforms a BPMN model into a multi-modal model that combines Discrete Event(DE)modeling for concurrency with Hierarchical State Machines(HSMs)to represent application ***,further transformations are used to transform the DE-HSM model into methods in smart *** system lets the modeler decide which of the independent patterns should be transformed into methods of a separate smart contract that is deployed on a sidechain for the purpose of(i)reducing processing costs and/or(ii)providing privacy so that other participants in the smart contract do not have visibility into the processing of the *** also briefly describe a proof-of-concept tool we built to demonstrate the feasibility of our approach.

关键词： Blockchain Business processes modeling notation(BPMN) Discrete event(DE)modeling Finite state machine(FSM) Hierarchical state machines(HSM) Smart contract Off-chain computation Privacy Smart contract interoperability

Heritability and Variability of Quality Parameters of Tomatoes in Outdoor Production

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Research 2020年第1期2020卷 1099-1107页

作者： christian Zorb Hans-peter Piepho Sabine Zikeli Bernd Horneburg University of Hohenheim Institute of Crop Science70593 StuttgartGermany University of Kassel Section of Organic Plant Breeding and Agrobiodiversity27213 WitzenhausenGermany

The tomato is the most important vegetable *** England,outdoor tomatoes are widely grown by amateur gardeners,with the number of their allotment plots exceeding *** instance,in Germany,only about 16%of tomato plants are cultivated according to organic standards,although these rates are expected to *** for yield and fruit quality can increase resource ***,we need to evaluate the variability of yield and fruit quality parameters,to calculate the heritability of these traits and to identify superior genotypes for organic outdoor tomato production and *** these aims,we grew 24 tomato genotypes of diverse origins in a two-year field *** heritability of quality traits such as glucose,fructose,organic acid,and lycopene was *** medium heritability for yield suggests that trials with a larger number of locations are needed for the reliable selection of this *** correlations of sugar concentrations with fruit weight and of organic acid concentration with fruit weight and yield suggest trade-offs in breeding for larger fruits and higher *** for increased lycopene content is not subject to these challenges;the concentrations of the primary metabolite sugars and organic acids are positively correlated.

关键词： breeding sugar exceeding

Modeling the Middle Jurassic ocean circulation

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Journal of Palaeogeography 2015年第4期4卷 373-386页

作者： Maura Brunetti christian Vérard peter O.Baumgartner Institute for Environmental Sciences University of Geneva Institute of Earth Sciences University of Lausanne

We present coupled ocean-sea-ice simulations of the Middle Jurassic（~165 Ma） when Laurasia and Gondwana began drifting apart and gave rise to the formation of the Atlantic Ocean. Since the opening of the Proto-Caribbean is not well constrained by geological records, configurations with and without an open connection between the Proto-Caribbean and Panthalassa are examined. We use a sea-floor bathymetry obtained by a recently developed three-dimensional（3D） elevation model which compiles geological, palaeogeographical and geophysical data. Our original approach consists in coupling this elevation model, which is based on detailed reconstructions of oceanic realms, with a dynamical ocean circulation model. We find that the Middle Jurassic bathymetry of the Central Atlantic and Proto-Caribbean seaway only allows for a weak current of the order of 2 Sv in the upper 1000 m even if the system is open to the West. The effect of closing the western boundary of the Proto-Caribbean is to increase transport related to barotropic gyres in the southern hemisphere and to change water properties, such as salinity, in the Neo-Tethys. Weak upwelling rates are found in the nascent Atlantic Ocean in the presence of this superficial current and we discuss their compatibility with deep-sea sedimentological records in this region.

关键词： Jurassic modeling ocean circulation palaeoclimate

Complex Effective Relative Permittivity of Soil Samples from the Taunus Region (Germany)

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Journal of Earth Science 2010年第6期21卷 961-967页

作者： Katja Lauer christian Albrecht Christina Salat peter Felix-Henningsen Institute of Soil Science and Soil Conservation Research Centre for BioSystems Land Use and Nutrition (IFZ) Justus-Liebig-University Giessen Department of Underground Space for Storage and Economic Use Federal Institute for Geosciences and Natural Resources

The most important parameter affecting ground-penetrating radar （GPR） measurements is the complex effective relative permittivity εr^＊,eff because it controls the propagation velocity and the reflection of GPR pulses. Knowing εr^＊,eff of soils passed through by electromagnetic waves increases accuracy in soil thickness and interface identification. Complex effective relative permittivity εr^＊,eff= εr^＊,eff - jεr^＊,effof 25 soil samples with textures ranging from loamy sand to silty clay was measured using the two-electrode parallelplate method. The measurements were conducted at defined water contents for frequencies from 1 MHz to 3 GHz. The results confirm the frequency dependence of εr^＊,eff and show that the dielectric behavior of soil-water mixtures is a function of water content. Applying the experimental data of this study with predictions based on the empirical model by Toppet aL （1980）, we find that Topp et aL＇s curve tends to underestimate the real part of εr^＊,eff measured. Along with frequency and water content, soil texture and organic matter affect soil permittivity. Moreover, the real part of εr^＊,eff increases at higher dry bulk densities. Output from our calibration model enables us to predict εr^＊,eff for the soil samples which were tested under the actual in situ soil water content. This results in high accuracy of soil thickness prediction.

关键词： ground-penetrating radar (GPR) complex effective relative permittivity soil sample.

Regular nicotine intake increased tooth movement velocity,osteoclastogenesis and orthodontically induced dental root resorptions in a rat model

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International Journal of Oral Science 2017年第3期9卷 174-184页

作者： christian kirschneck michael maurer michael wolf claudia reicheneder peter proff department of orthodontics university medical centre of regensburgRegensburgGermany department of oral and maxillofacial surgery university medical centre of regensburgRegensburgGermany department of orthodontics rheinische friedrich wilhelm university of bonnBonnGermany

Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.

关键词： dental research inbred Fischer344 nicotine orthodontics rats root resorption tooth movement