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中国科技教育 2015年第1期 8-15页

作者： hubert m.dyasi 陈彧美国国家研究理事会K—12年级科学教育委员会国际科学院组织科学教育项目全球活动委员会中国科协"做中学"科学教育实验项目教学中心(东南大学)

2014年10月28-30日，国际科学院组织（IAP）科学教育国际研讨会在北京召开。来自19个国家．100多名科学院的院士和科学家，高校和数育研究机机构的专家学者，科技馆，薄雾馆的科学教育工作者，学校教师。

关键词：科学教育技术教育专题连接国际研讨教育工作者专家学者科学院

不仅是事实和公式:小学课堂中的探究式科学教育究竟是什么

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中国科技教育 2015年第7期 8-12页

作者： hubert m.dyasi 周建中

2015年6月,由中国青少年科技辅导员协会主办的2015科学教育国际论坛,以“基于探究的科学教育”为主题,邀请到国内外知名科学教育学者、专家,以及众多一线科学教师汇聚南京,围绕探究式科学教育的发展与实践,尤其是科学教育与技术教育的... 详细信息

2015年6月,由中国青少年科技辅导员协会主办的2015科学教育国际论坛,以“基于探究的科学教育”为主题,邀请到国内外知名科学教育学者、专家,以及众多一线科学教师汇聚南京,围绕探究式科学教育的发展与实践,尤其是科学教育与技术教育的结合、探究式科学教育的资源支持,以及科学探究技能等主题,进行了深入的交流与探讨。本刊将分2期为读者呈现全部7个精彩的主旨演讲内容。本期专题中,hubert dyasi教授详细介绍了探究式科学教育在小学课堂中的模样及评测方式;Jacob Foster博士详细介绍了美国《新一代科学教育标准》的内容结构及其与以往标准的不同;戴耘教授结合丰富的案例介绍了美国通过学生的探究和研究活动培养科学人才的经验。

关键词：教育学者小学课堂教育标准内容结构案例介绍技术教育主旨演讲 Foster 录音整理演讲人

Energy dissipation on stepped spillways and hydraulic challenges—Prototype and laboratory experiences

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Journal of Hydrodynamics 2022年第1期34卷 52-62页

作者： hubert Chanson School of Civil Engineering The University of QueenslandBrisbaneAustralia

Stepped cascades, chutes and spillways have been in use for more than three millennia. With the introduction of new construction materials and techniques, the staircase chute design has regained some interest within the last forty years. The stepped invert increases significantly the energy dissipation occurring above the steep chute and reduces the size of the required downstream stilling structure. The application of stepped chutes further encompasses in-stream re-aeration and water treatment plant cascades, to enhance the air-water transfer of atmospheric gases and of volatile organic components. However, the engineering design of stepped spillways is not simple because of the hydrodynamic challenges, with several markedly different flow regimes, some complicated two-phase air-water fluid dynamics and massive rate of energy dissipation above the stepped chute. Simply, the technical challenges in the hydraulic design of stepped spillways are massive. This review paper examines the hydraulic characteristics of stepped chute flows and develops a reflection on nearly three decades of active hydraulic research, including recent field measurements during major flood events. The author aims to share his passion for the complicated hydraulic engineering, as well as some advice for engineering professionals and researchers.

关键词： Stepped spillways hydraulic modeling field measurements energy dissipation and design multiphase air-water flows

Deterministic Homogenization of Nonlinear Degenerate Elliptic Operators with Nonstandard Growth

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Acta mathematica Sinica,English Series 2014年第9期30卷 1621-1654页

作者： hubert NNANG University of Yaounde I Ecole Normale Suprieure de Yaound

We study the deterministic homogenization of nonlinear degenerate elliptic equations with nonstandard growth. One fundamental in this topic is to extend the classical compactness results of the E-convergence method to the Orlicz spaces. We also show that one can homogenize nonlinear Dirichlet problems in a general way by leaning on a simple abstract hypothesis contrary to what has been done in the determinstic homogenization theory.

关键词： Determinstic homogenization degenerate operator H-algebras Orlicz-Sobolev spaces

Bubble entrainment, spray and splashing at hydraulic jumps

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1396-1405页

作者： CHANSON hubert Division of Civil Engineering The University of Queensland Brisbane QLD 4072 Australia

The sudden transition from a high-velocity, supercritical open channel flow into a slow-moving sub-critical flow is a hydraulic jump. Such a flow is characterised by a sudden rise of the free-surface, with some strong energy dissipation and air entrainment, waves and spray. New two-phase flow measurements were performed in the developing flow region using a large-size facility operating at large Reynolds numbers. The experimental results demonstrated the complexity of the flow with a developing mixing layer in which entrained bubbles are advected in a high shear stress flow. The relationship between bubble count rates and void fractions was non-unique in the shear zone, supporting earlier observations of some form of double diffusion process between momentum and air bubbles. In the upper region, the flow consisted primarily of water drops and packets sur-rounded by air. Visually significant pray and splashing were significant above the jump roller. The present study is the first com-prehensive study detailing the two-phase flow properties of both the bubbly and spray regions of hydraulic jumps, a first step towards understanding the interactions between bubble entrainment and droplet ejection processes.

关键词： Hydraulic jump Air bubble entrainment Spray and splashing physical modelling Particle chord time distributions

Two-phase air-water flows: Scale effects in physical modeling

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Journal of Hydrodynamics 2014年第2期26卷 291-298页

作者： PFISTER michael CHANSON hubert Ecole Polytechnique Fédérale de Lausanne (EPFL) Laboratory of Hydraulic Constructions (LCH) The University of Queensland School of Civil Engineering

Physical modeling represents probably the oldest design tool in hydraulic engineering together with analytical approaches. In free surface flows, the similitude based upon a Froude similarity allows for a correct representation of the dominant forces, namely gravity and inertia. As a result fluid flow properties such as the capillary forces and the viscous forces might be incorrectly reproduced, affecting the air entrainment and transport capacity of a high-speed model flow. Small physical models operating under a Froude similitude systematically underestimate the air entrainment rate and air-water interfacial properties. To limit scale effects, minimal values of Reynolds or Weber number have to be respected. The present article summarizes the physical background of such limitations and their combination in terms of the morton number. Based upon a literature review, the existing limits are presented and discussed, resulting in a series of more conservative recommendations in terms of air concentration scaling. For other air-water flow parameters, the selection of the criteria to assess scale effects is critical because some parameters （e.g., bubble sizes, turbulent scales） can be affected by scale effects, even in relatively large laboratory models.

关键词： air entrainment hydraulic structures physical modeling scale effects two-phase flow morton number

Diagnosing Battery Degradation via Gas Analysis

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Energy & Environmental materials 2022年第3期5卷 688-692页

作者： michael metzger hubert A.Gasteiger Department of Physics and Atmospheric Science Dalhousie UniversityHalifax Nova Scotia B3H 4R2Canada Department of Chemistry Dalhousie UniversityHalifax Nova Scotia B3H 4R2Canada Chair of Technical Electrochemistry Department of Chemistry and Catalysis Research CenterTechnical University of MunichD-85748Garching Germany

Interfacial reactions in lithium-ion batteries often involve gaseous reaction *** investigation of material degradation processes requires a technique to identify and quantify these gases in battery *** electrochemical mass spectrometry(OEmS)is an operando gas analysis method that continuously samples the headspace of a custom battery ***-time gas analysis by quantitative OEmS was used to create mechanistic understanding of battery degradation reactions,some of which will be highlight in this article.

关键词： aging mechanisms batteries energy storage gas analysis in situ and operando characterization

Vacuum Furnace - Integrated“Sub zero” Treatment

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材料热处理学报 2004年第5期25卷 588-590页

作者： B. Zieger hubert Schulte SCHmETZ GmbH Menden GermanySCHMETZ GmbH Menden Germany

The vacuum heat treatment with overpressure gas quenching is more and more accepted due to considerable advantages compared to the traditional oil and salt bath processes. Continuous further developments and new concepts like multi-directional cooling systems, a separate quenching chamber and "sub zero" systems lead towards an oxidation free and low distortion vacuum heat treatment for a broad range of parts and materials. Short and energy saving processes guarantee a high economic efficiency and environmental compatibility. The "sub zero" system which is integrated into the standard vacuum furnace achieves a heat treatment result with a high conversion of retained austenite in fully automatic hardening and tempering processes.

关键词：真空炉真空热处理深度冷冻过压气体流淬火

The Plastics Industry:Worldwide and European Overview

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塑料工业 2013年第S1期41卷 34-52页

作者： hubert SImON ISO/TC(Plastics)

Stochastic-periodic Homogenization of maxwell＇s Equations with Linear and Periodic Conductivity

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Acta mathematica Sinica,English Series 2017年第1期33卷 117-152页

作者： Joel FOTSO TACHAGO hubert NNANG Faculty of Science Department of Mathematics and Computer Science University of Bamenda P. O. Box 39 Bambili Cameroon Higher Teachers Training College University of Yaounde I P. O. Box 47 Yaounde Cameroon

Stochastic-periodic homogenization is studied for the maxwell equations with the linear ＂and periodic electric conductivity. It is shown by the stochastic-two-scale convergence method that the sequence of solutions t... 详细信息

关键词： maxwell's equations dynamical system stochastic two-scale convergence