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151.
The article introduces the Microfeature Catalogue as an information database that is structured by Microfeatures and can be used for preventive and non-preventive quality assurance. The Microfeature conception is adapted and evaluated in the specific fabrication environment of micro mechanical components. The production of micro parts demands a further development of the new fabrication technologies on the one hand and an appropriate development of the concomitant processes such as the quality assurance process on the other hand. A coherent information cycle between design, fabrication and quality assurance is put into practice. 相似文献
152.
Juergen Strohal 《世界电子元器件》2011,(5):36-38
电子领域的工程人员,特别是汽车电子领域,必然将比以往遇到更多的有关EMC的问题。自无线电发明以来,无线电干扰现象几乎一直伴随其左右,在早期就催生了各种噪声抑制定义指引。EMC的另一部分——抗失真能力,却仅在约50年前才开始受到关注。 相似文献
153.
Samuel Owusu Yeboah Yulita Chebotip Mitei Jane Catherine Ngila Ludger Wessjohann Juergen Schmidt 《Journal of the American Oil Chemists' Society》2011,88(10):1539-1549
The lipid components of three Cameroonian seed oils, ke tchock (Aframomum arundinaceum), njangsa (Ricinodendron heudelotii) and calabash nutmeg (Monodora myristica), have been investigated. Gas chromatography (GC)–mass spectrometry (MS) fatty acid (FA) analysis showed M. myristica seed oil to be dominated by linoleic (49.29%) and oleic (37.17%) acids; R. heudelotii was mainly linoleic (58.73%), followed by stearic (15.00%) and oleic (14.21%) acids; A. arundinaceum was predominantly oleic (65.76%) and palmitic (20.36%) acids. Electrospray ionization (ESI)-Fourier transform ion cyclotron
resonance (FTICR)-MS analysis showed seven major triacylglycerol (TAG) classes for M. myristica, with C54:5, C54:4 and C54:6 dominating. R. heudelotii had eight major TAG classes with C54:8, C54:7 and C54:6 being most abundant. A. arundinaceum also had eight major TAG classes with C52:2, C54:3 and C50:2 dominating. 13C nuclear magnetic resonance (NMR) analysis of the TAGs showed that both sn-1,3 and sn-2 positions were predominantly occupied by linoleoyl and oleoyl chains. High-performance liquid chromatography (HPLC) fluorescence
detector (FLD) analysis showed that M. myristica contained only α- and β-tocopherols (195.40 and 73.95 μg/g, respectively), R. heudelotii contained mainly γ-tocopherol (289.40 μg/g), and A. arundinaceum had mainly γ- and β-tocopherols (236.78 and 124.93 μg/g, respectively). GC–MS analysis of the unsaponifiable matter showed
that β-sitosterol was the most abundant phytosterol in all three seed oils. The absolute amounts of 4-desmethylsterols were
196.15, 608.71 and 362.15 μg/g for M. myristica, R. heudelotii and A. arundinaceum seed oils, respectively. These compositional and structural studies provide justification for the use of all three seed oils
in food products. 相似文献
154.
Minimizing steel corrosion in liquid lead-alloys by addition of oxygen requires devices for efficient oxygen transfer and reliable oxygen sensors. The accuracy of electrochemical oxygen sensors is analyzed using theoretical considerations and results from experiments in stagnant lead–bismuth eutectic (LBE). Additionally, the feasibility of gas/liquid oxygen-transfer and the long-term performance of electrochemical sensors in flowing liquid metal are addressed on the basis of the operating experience of the CORRIDA loop, a facility for testing steels in flowing LBE. 相似文献
155.
156.
Juergen Sauer Alain Chavaillaz David Wastell 《Theoretical Issues in Ergonomics Science》2017,18(3):279-297
This article examines the effectiveness of different forms of performance-based adaptive automation (PBAA). Using data from three experiments (N = 10, N = 38, N = 40), different models of algorithm design were compared for their effectiveness in driving PBAA. The following components were varied: type of task (i.e. primary or secondary tasks), baseline of performance data (e.g. moving average), and triggering criterion (i.e. level of deviation from standard performance). The data were generated by operators working with a computer-based simulation of a process control environment. The results showed that none of the models enjoyed a convincing level of effectiveness. The automation algorithms generally achieved higher levels of miss prevention than false alarm prevention. Surprisingly, primary task performance was generally better at driving PBAA than secondary task performance. The results suggest that it may be difficult to design an effective algorithm of PBAA if the work environment is highly complex. 相似文献
157.
Inside Cover: Targeted Delivery of Proteasome Inhibitors to Somatostatin‐Receptor‐Expressing Cancer Cells by Octreotide Conjugation (ChemMedChem 12/2015) 下载免费PDF全文
158.
Hans Juergen Seifert 《中国材料进展》2015,34(4)
CALPHAD结合关键实验可以探究能源材料体系的多元多相反应.介绍了4个基于不同应用背景的合金体系的评估工作:液相烧结的SiC(LPSSiC)体系、转换型锂离子电池体系、掺杂Cr的TiAl基合金体系以及Zr基热障涂层体系.研究结果显示:CALPHAD热力学计算结果可以用于指导关键实验设计,从而进一步明确研究体系的相图和热力学性质.获得的实验数据又可以作为精炼CALPHAD模型和改进模型参数的输入条件.精炼后的模型参数构成的热力学数据库可用于计算各种相图(包括等温截面、垂直截面、可以用来计算可信的相图(等温截面、垂直截面及波动图)及液相面投影图. 相似文献
159.
Alicja Bachmatiuk Jiong Zhao Sandeep Madhukar Gorantla Ignacio Guillermo Gonzalez Martinez Jerzy Wiedermann Changgu Lee Juergen Eckert Mark Hermann Rummeli 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(5):515-542
The initial isolation of graphene in 2004 spawned massive interest in this two‐dimensional pure sp2 carbon structure due to its incredible electrical, optical, mechanical, and thermal effects. This in turn led to the rapid development of various characterization tools for graphene. Examples include Raman spectroscopy and scanning tunneling microscopy. However, the one tool with the greatest prowess for characterizing and studying graphene is the transmission electron microscope. State‐of‐the‐art (scanning) transmission electron microscopes enable one to image graphene with atomic resolution, and also to conduct various other characterizations simultaneously. The advent of aberration correctors was timely in that it allowed transmission electron microscopes to operate with reduced acceleration voltages, so that damage to graphene is avoided while still providing atomic resolution. In this comprehensive review, a brief introduction is provided to the technical aspects of transmission electron microscopes relevant to graphene. The reader is then introduced to different specimen preparation techniques for graphene. The different characterization approaches in both transmission electron microscopy and scanning transmission electron microscopy are then discussed, along with the different aspects of electron diffraction and electron energy loss spectroscopy. The use of graphene for other electron microscopy approaches such as in‐situ investigations is also presented. 相似文献
160.
El Ghazi I Menge S Miersch J Chafik A Benhra A Elamrani MK Krauss GJ 《Environmental science & technology》2003,37(24):5739-5744
A HPLC-fluorescence method, using the fluorophore SBD-F (ammonium-7-fluorobenz-2-oxa-1,3-diazole-4-sulfonate), was adapted for the quantification of metallothioneins and their isoforms from the Moroccan mussel Mytilus galloprovincialis. The method was first optimized using a rabbit liver metallothionein. The effects of EDTA, tris(2-carboxyethyl)phosphine, and SBD-F on the labeling efficiency were studied. The optimized method was then applied to evaluate the amount of metallothionein in the mussels either exposed to cadmium in the laboratory or collected from the Casablanca coast, Morocco. The concentrations of metallothioneins measured in the field samples describe the degree of contamination of the sites and are reflected by distinct isoform patterns. 相似文献