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Formation of primary intermetallic phases in the interaction of Fe-containing melts of recycled Al-Si alloys with Al_(2)O_(3)and Al_(2)O_(3)-C filter materials:Aμ-CT study

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Journal of Materials Science & Technology 2024年第17期184卷 88-100页

作者： h.becker B.Fankhänel A.Charitos S.Baier-Stegmaier A.Leineweber W.Pantleon Institute of Materials Science TU Bergakademie FreibergGustav-Zeuner-Straße 509599 FreibergGermany Institute of Nonferrous Metallurgy and Purest Materials TU Bergakademie FreibergLeipziger Straße 3409599 FreibergGermany Department of Physics Technical Univeristy of DenmarkFysikvej 3102800 Kgs.LyngbyDenmark Department of Civil and Mechanical Engineering Technical Univeristy of DenmarkProduktionstorvet 4252800 Kgs.LyngbyDenmark

Fe is the most detrimental impurity element in recycled Al-Si alloys due to the formation of brittle,primary,Fe-containing,intermetallic particles during *** removal from the Al-Si melts *** filtration can reduce the Fe *** active filter materials can facilitate the formation of these particles for their removal and contribute to the production of high-quality,recycled Al-Si *** interaction of the alloy with the filter material can lead to modification of the thermodynamics of the alloy or of the kinetics of the particle ***-resolved,three-dimensional microstructural inves-tigations have been carried out to study the formation of primary intermetallic particles in Al7.1Si1.5Fe and Al7.1Si0.75Fe0.75Mn alloy melts in contact with Al_(2)O_(3)and Al_(2)O_(3)-C filter substrate material during a melt conditioning treatment at 620°*** microstructures,in particular the primary intermetallic particlesαc andαh,have been characterized by computed tomography(CT)and supplementary scanning electron microscopy(SEM).As expected by thermodynamics,the total volume fraction of primary par-ticles remains unchanged by the interaction with the substrate ***,kinetic advantages for Fe-removal efficiency can be achieved by an accelerated and preferred selective particle formation in contact with the Al_(2)O_(3)-C ***,particle formation is discussed in view of its different stages:nucleation,growth,and ripening.

关键词： Aluminum alloys Intermetallic phases Solidification X-ray computed tomography Scanning electron microscopy

Model Experiments on Melting of Alloys with Low Melting Temperature in a Medium with high Melting Temperature

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Journal of Iron and Steel Research International 1999年第2期6卷 1-9页

作者： becker Jens-Ulrik Oeters Franz Thyssen-Krupp Stahl Gmbh Technical University Berlin

Experiments of alloy melting were carried out in water/hCl h 2O eutectic model system. The eutectic has a solid liquid equilibrium temperature of -74 ℃. 5 cm diameter spheres of the eutectic in which three thermocouples in the core, on the edge and in the middle between them had been positioned were cooled to -196 ℃ in liquid nitrogen. After cooling the spheres were immersed into water of 10 ℃, and the changes of temperatures with time in the three thermocouples were measured. In some experiments the temperature on the outer side of the spheres where an ice shell grew up was also measured. In these experiments, the growing rate of the shell was additionally determined. The results for the first minute of the melting process, where the system can be considered as one dimensional, were described by an exact solution of Fouriers equation. The density of liquid ferromanganese at 1 500 ℃ was measured.

关键词： alloy melting model experiment

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Micro-Structured Fiber Interferometer as Sensitive Temperature Sensor

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Photonic Sensors 2013年第3期3卷 208-213页

作者： F. C. FAVERO M. becker, R. SPITTEL M. ROThhARDT J. KOBELKE h. BARTELT Institute of Photonic Technology (IPhT) Albert-Einstein-Strafle-9 07745 Jena Germany

We report on a fast and sensitive temperature sensor using a micro-structured or photonic crystal fiber interferometer with a high germanium doped fiber core. The wavelength sensitivity for temperature variation was as high as △λ/△T= 78 pm/℃ up to 500℃, which was 6 times more sensitive than the fiber Bragg grating temperature sensitivity of △λ/△TT= 13pm/℃ at 1550nm. The sensor device was investigated conceming the sensitivity characteristics and response time.

关键词： Micro-structured optical fiber fiber interferometer fiber temperature sensor

Agricultural growing season calendars derived from MODIS surface reflectance

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International Journal of Digital Earth 2015年第3期8卷 173-197页

作者： Alyssa K.Whitcraft Inbal becker-Reshef Christopher O.Justice Department of Geographical Sciences University of MarylandCollege ParkMDUSA

In order to secure the necessary image acquisitions for global agricultural monitoring applications,we must first articulate Earth observation(EO)requirements for diverse agricultural landscapes and cropping *** to this task is the identification of agricultural growing season timing at a meaningful spatial scale,so as to better define the necessary periods of image *** this end,10 years of MODIS Terra Surface Reflectance imagery have been used to determine phenological transition dates including start of season,peak period,and end of season at 0.5°*** is the first set of global,satellite-derived,cropland-specific calendar dates for major field crops within a 0.5°,herein called agricultural growing season calendars Preliminary comparison against ground-based crop-specific calendars is performed,highlighting the utility of this approach for articulating growing season timing and its interannual and within-region *** research provides critical inputs for defining the EO requirements for the Global Agricultural Monitoring initiative(GEOGLAM),an effort by the Group on Earth Observations(GEO)to synergize existing national and regional observation systems for improved agricultural production and food security monitoring.

关键词： agriculture vegetation indices Earth observation data acquisition remote sensing

同工酶分子标记研究中国和欧洲栽培油菜的遗传差异

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作物学报 1998年第2期24卷 213-220页

作者：赵坚义 h.C.becker 浙江省农科院作物所浙江杭州310021 瑞典农业大学作物育种研究所瑞典26831

本研究于1993～1994年在瑞典农业大学作物遗传育种研究所进行,旨在比较中国和欧洲甘蓝型和白菜型油菜品种的遗传差异;现有资源的基因丰富程度及基因多样性的分布规律,为科学地评价和合理地利用品种资源提供重要参考。我们分析了36个和4... 详细信息

本研究于1993～1994年在瑞典农业大学作物遗传育种研究所进行,旨在比较中国和欧洲甘蓝型和白菜型油菜品种的遗传差异;现有资源的基因丰富程度及基因多样性的分布规律,为科学地评价和合理地利用品种资源提供重要参考。我们分析了36个和41个来自中国、加拿大和欧洲国家的白菜型和甘蓝型油菜品种的7种同工酶的酶谱,用淀粉凝胶和醋酸纤维薄膜电泳在白菜型油菜中得到8个同工酶基因位点36个等位基因;甘蓝型油莱中得到12个基因位点32个等位基因。在此基础上进行基因多样性、遗传距离和聚类分析。试验结果表明: 1.白菜型油菜品种内个体间呈高度基因多态性,占总变异的70％左右;在甘蓝型油菜中,品种间的基因多样性占总变异的80％左右。 2.聚类和主成分分析表明中国和欧洲的白菜型油菜具有完全不同的遗传背景;欧洲白菜型的冬性和春性油菜又分属两大基因亚群。 3.甘蓝型油菜没有如此明显的地域界限,但欧洲冬性和春性油莱具有相对独立的遗传组成。大多数中国“双高”地方品种与欧洲、加拿大油菜表现出较大的遗传差异,而绝大多数中国“双低”品种界于中国“双高”和欧洲、加拿大品种之间。据此,充分利用中国和欧洲、加拿大白菜型油菜及中国“双高”和欧洲、加拿大“双低”甘蓝型油菜基因于育种研究,无疑是扩大遗传背?

关键词：油菜同功酶分子标记栽培遗传差异油料作物

h_(∞)control in the frequency domain for a semi-active floor isolation system

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Frontiers of Structural and Civil Engineering 2013年第3期7卷 264-275页

作者： Yundong ShI Tracy C becker Masahiro KURATA Masayoshi NAKAShIMA Graduate School of Engineering Kyoto UniversityKyoto 611-0011Japan Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect *** this configuration,the input motions to the floor isolation from the ground motions are filtered by the structure,leaving the majority of the frequency content of the input motion lower than the predominant frequency of the *** floor isolation system should minimize the acceleration to protect equipment;however,displacement must also be limited to save floor space,especially with long period ***-active control with an h_(∞)control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the h_(∞)control.A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the h_(∞)*** control using an oil damper was also tested for *** test results show that the h_(∞)control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure,as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation *** h_(∞)control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词： semi-active floor isolation h1 control MR damper shaping filter shaking table test

Flexible, diamond-based microelectrodes fabricated using the diamond growth side for neural sensing

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Microsystems & Nanoengineering 2020年第1期6卷 742-753页

作者： Bin Fan Cory A.Rusinek Cort h.Thompson Monica Setien Yue Guo Robert Rechenberg Yan Gong Arthur J.Weber Michael F.becker Erin Purcell Wen Li Department of Electrical and Computer Engineering Michigan State UniversityEast LansingMIUSA Fraunhofer USA Center for Coatings and Diamond Technologies East LansingMIUSA Department of Biomedical Engineering Michigan State UniversityEast LansingMIUSA Department of Physiology Michigan State UniversityEast LansingMIUSA

Diamond possesses many favorable properties for biochemical sensors,including biocompatibility,chemical inertness,resistance to biofouling,an extremely wide potential window,and low double-layer *** hardness of diamond,however,has hindered its applications in neural implants due to the mechanical property mismatch between diamond and soft nervous ***,we present a flexible,diamond-based microelectrode probe consisting of multichannel boron-doped polycrystalline diamond(BDD)microelectrodes on a soft Parylene C *** developed and optimized a wafer-scale fabrication approach that allows the use of the growth side of the BDD thin film as the sensing *** to the nucleation surface,the BDD growth side exhibited a rougher morphology,a higher sp^(3) content,a wider water potential window,and a lower background *** dopamine(DA)sensing capability of the BDD growth surface electrodes was validated in a 1.0 mM DA solution,which shows better sensitivity and stability than the BDD nucleation surface *** results of these comparative studies suggest that using the BDD growth surface for making implantable microelectrodes has significant advantages in terms of the sensitivity,selectivity,and stability of a neural ***,we validated the functionality of the BDD growth side electrodes for neural recordings both in vitro and in *** biocompatibility of the microcrystalline diamond film was also assessed in vitro using rat cortical neuron cultures.

关键词： neural film diamond

质粒DNA物理形态和其它因素对获得可育转基因小麦的影响

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实验生物学报 2001年第3期34卷 183-189页

作者：徐子勤 D.becker h.Lrz 西北大学生物技术省重点实验室西安710069 德国汉堡大学普通植物学研究所汉堡d22609

本工作分析了不同形态质粒DNA和未成熟胚高渗透压处理对基因枪小麦转化体系的适用性。高渗处理对瞬间表达和转基因小麦的再生均有明显的促进作用。轰击之前对质粒DNA进行变性处理导致瞬间表达反应大幅度下降,但稳定转化频率(指从100个... 详细信息

本工作分析了不同形态质粒DNA和未成熟胚高渗透压处理对基因枪小麦转化体系的适用性。高渗处理对瞬间表达和转基因小麦的再生均有明显的促进作用。轰击之前对质粒DNA进行变性处理导致瞬间表达反应大幅度下降,但稳定转化频率(指从100个轰击未成熟胚得到的再生可育转基因植株数)与双链DNA相差不大。使用单链质粒DNA、线性双链质粒DNA和环状双链质粒DNA均可以得到转基因小麦植株。迄今已得到26个不同的转基因冬小麦株系和4个不同的转基因春小麦株系。这些转基因小麦大多数已产生种子,几个春小麦株系已获第二代种子。

关键词：转基因小麦质粒DNA 物理形态稳定转化育性

Role of receptor tyrosine kinases in gastric cancer: New targets for a selective therapy

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World Journal of Gastroenterology 2006年第21期12卷 3297-3305页

作者： JC becker C Müller-Tidow h Serve W Domschke T Pohle Department of Medicine B University of Münster D-48129 MünsterGermany Department of Medicine A University of Münster D-48129 MünsterGermany

Receptor tyrosine kinases （RTKs） such as the epidermal growth factor receptor family participate in several steps of tumor formation including proliferation and metastatic spread. Several known RTKs are upregulated in gastric cancer being prime targets of a tailored therapy. Only preliminary data exist, however, on the use of the currently clinically available drugs such as trastuzumab, cetuximab, bevacizumab, gefitinib, erlotinib, and imatinib in the setting of gastric cancer. Preclinical data suggest a potential benefit of their use, especially in combination with ＂conventional＂ cytostatic therapy. This review summarizes the current knowledge about their use in cancer therapy as well as new approaches and drugs to optimize treatment success.

关键词： Gastric carcinoma EGFR Gefitinib Trastuzumab Cetuximab Imatinib Erlotinib Bevacizumab