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Investigations on the aging behavior of transparent bioplastics for optical applications

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InfoMat 2020年第2期2卷 424-433页

作者： Jana Baltscheit Nico Schmidt finn Schröder Jörg Meyer Photonics and Materials Science Hamm-Lippstadt University of Applied ScienceLippstadtGermany Department of Natural Science Paderborn UniversityPaderbornGermany

In this study,the optical properties of transparent bioplastics have been *** long-term technological goal is to establish biopolymers in a new market segment for demanding optical applications and to contribute to a more sustainable economy.A collection of transparent bioplastics has been tested with respect to the long-term stability and the possibility of an application in optical components for LED *** focus of materials testing was on the influence of short wavelength visible radiation as well as thermal *** results show,that some materials may be candidates for subsequent feasibility *** the best of our knowledge,the application of such polymers in complex technical products and in particular in luminaires has not yet been *** use of bio-based plastics for optical components therefore represents a novelty and has a high development potential.

关键词： (blue)LED irradiance (photo)degradation biobased plastics renewable materials transparent optics

Documenting aftermath

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Documenting aftermath

Demonstrating mate choice copying in spiders requires further research

作者： Megan finn.

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Current Zoology 2020年第2期66卷 215-216页

作者： R.Tucker GILMAN Kasey FOWLER-finn Eileen A.HEBETS School of Earth and Environmental Sciences The University of ManchesterManchesterUK Department of Biology Saint Louis UniversitySt.LouisUSA School of Biological Sciences University of Nebraska-LincolnLincolnNEUSA

Mate choice copying-when individuals learn to prefer mates or mate types that have been chosen by others-can influence trait evo-lution and speciation(Varela et al.2018;Dion et al.2019).Most examples of mate choice copying are from fish,birds,and mammals including humans(Varela et al.2018).However,2 invertebrate examples-fruit flies and wolf spiders-have been used to argue that the phenomenon may be phylogenetically widespread,and perhaps the rule rather than the exception in nature(Varela et al.2018).Here,we revisit the evidence for mate choice copying in wolf spiders(Fowler-Fimn et al.2015)in light of new data(Gilman et al.2018).Then,we discuss why mate choice copying is a phenomenon that is likely to occur in wolf spiders,and why this deserves attention.

关键词： invertebrates mate choice copying Schizocosa sexual selection speciation spiders

A novel method of quantifying the coating progress in a three-dimensional prismatic spouted bed

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Particuology 2019年第1期17卷 137-145页

作者： Swantje Pietscha finn Ole Poppinga Stefan Heinrich Michael Müller Michael Schonherr Frank Kleine Jager Hamburg University of Technology Institute of Solids Process Engineering and Particle TechnologyDenickestraβe 1521073 HamburgGermany BASF SE RCP/TT67056 LudwigshafenGermany

An optical method of experimentally quantifying the coating progress in a laboratory prismatic spouted bed is presented. Microcrystalline cellulose particles with size dp = 0.57 mm are used as core material. Waterborne coating suspensions with methylene blue as a dye are used and sprayed via a two-fluid nozzle in bottom-spray configuration. A high-speed camera with a color filter is positioned in front of the observation window of the three-dimensional plant and records the flow pattern in the process chamber with a certain frequency. With increasing surface coverage, the particles become bluer and darker. The change in brightness is detected by digital image analysis. In the implemented algorithm, the spherical particles are detected, cut from the background and normalized regarding their lighting and area. The detection of coated pixels on the single particles allows the calculation of the coating fraction and coating uniformity after a Kalman filter has been applied to reduce noise. It is shown that the method can be used to determine the time needed to reach the maximum blue value indicating a complete coating of the particle bed. Besides the minimum coating duration, information on the spraying performance (e.g., the time point of a possibly occurring blockage of the nozzle) can be obtained from the data. Two exemplary experiments are presented, showing a connection of the slope of the coating fraction and the uniformity of the coating of the particles in the apparatus that results in the recommendation of a slow liquid injection for obtaining consistent coating layers as desired in many applications.

关键词： Spouted bed Particle coating Granulation Digital image analysis

The Mesozoic of Western Scandinavia and East Greenland

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Episodes 2008年第1期31卷 59-65页

作者： Arvid NФttvedt Erik P. Johannessen finn Surlyk Christian Michelsen Research Bergen Norway. StatoilHydro Stavanger Norway. Department of Geography and Geology University of Copenhagen Denmark.

Thick Mesozoic sediments are found offshore Norway and Denmark, and Mesozoic rocks are present and well exposed in Denmark, along the coast of East Greenland and on the arctic islands of Svalbard. During the Mesozoic, Scandinavia and Greenland were subject to major extension in the Late Permian-Early Triassic and Late Jurassic-Early Cretaceous, prior to Cenozoic opening of the North Atlantic. Deep basins developed along the rift zones of the North Sea and between East Greenland and Norwa）; and were .filled with sediments derived from mainland Scandinavia and Greenland. The marginal areas bordering the rift zones suffered less subsidence, as did the epicontinental Barents Sea.

关键词：中生代斯堪的纳维亚东格陵兰岛地质特征

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湍流对流动管道中声强测量的影响(英文)

船舶力学 2008年第3期12卷 505-515页

作者：史小军 finn JACOBSEN 中国船舶科学研究中心无锡214082 丹麦技术大学声学系丹麦2800

实际声强测量大多是在流动环境条件下进行,因此湍流对声强测量的影响是人们十分关心的工程实用问题。文章结合声强和湍流边界层等相关领域的技术,对流动条件下的声强技术进行了研究分析,导出了由湍流边界层引起的声强的具体表达式。应用... 详细信息

实际声强测量大多是在流动环境条件下进行,因此湍流对声强测量的影响是人们十分关心的工程实用问题。文章结合声强和湍流边界层等相关领域的技术,对流动条件下的声强技术进行了研究分析,导出了由湍流边界层引起的声强的具体表达式。应用Corcos建立的湍流边界层脉动压力模型,对湍流边界层脉动压力诱导的声强进行了数值计算分析,分析了测量传感器间距、马赫数等对声强测量的影响。

关键词：声学声强湍流管道

湍流边界层脉动压力对声强测量的影响研究(英文)

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船舶力学 2010年第3期14卷 314-323页

作者：史小军 finn JACOBSEN 中国船舶科学研究中心江苏无锡214082 丹麦技术大学声学系丹麦2800

实际声强测量时常常存在风流或水流,如在飞机或船舶上进行测量,声强探头将受到湍流边界层脉动压力的影响。如何评估该影响以及如何修正测量结果是人们十分关心的工程实用问题。该文首先简要介绍了建立的由湍流边界层脉动压力诱发声强的... 详细信息

实际声强测量时常常存在风流或水流,如在飞机或船舶上进行测量,声强探头将受到湍流边界层脉动压力的影响。如何评估该影响以及如何修正测量结果是人们十分关心的工程实用问题。该文首先简要介绍了建立的由湍流边界层脉动压力诱发声强的理论模型。接着利用现有的湍流边界层脉动压力频率-波数谱模型,对湍流边界层脉动压力及其诱发的声强进行了数值分析。为了验证理论模型及数值结果,设计制作了一套实验装置,对湍流边界层脉动压力及其产生的声强进行了具体测量分析。结果表明,湍流边界层脉动压力的测量结果与数值结果吻合良好,测量得到的边界层脉动压力诱发的声强特性与计算结果也十分一致,但必须注意对测量传感器的空间响应进行修正。

关键词：声学声强湍流边界层脉动压力

The complexities of female mate choice and male polymorphisms： Elucidating the role of genetics, age, and mate-choice copying

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Current Zoology 2015年第6期61卷 1015-1035页

作者： Kasey D. FOWLER-finn Laura SULLIVAN-BECKERS Amy M. RUNCK Eileen A. HEBETS School of Biological Sciences University of Nebraska Lincoln NE 68508 USA

Genetic, life history, and environmental factors dictate patterns of variation in sexual traits within and across popula- tions, and thus the action and outcome of sexual selection. This study explores patterns of inheritance, diet, age, and mate-choice copying on the expression of male sexual signals and associated female mate choice in a phenotypically diverse group of Schizo- cosa wolf spiders. Focal spiders exhibit one of two male phenotypes：＇omamented＇ males possess large black brushes on their fo- relegs, and ＇non-ornamented＇ males possess no brushes. Using a quantitative genetics breeding design in a mixed population of ornamented/non-ornamented males, we found a strong genetic basis to male phenotype and female choice. We also found that some ornamented males produced some sons with large brushes and others with barely visible brushes. Results of diet manipula- tions and behavioral mating trials showed no influence of diet on male phenotype or female mate choice. Age post maturation, however, influenced mate choice, with younger females being more likely to mate with ornamented males. A mate-choice copy- ing experiment found that, following observations of another female＇s mate choice/copulation, virgin mature females tended to match the mate choice （ornamented vs. non-ornamented males） of the females they observed. Finally, analyses of genetic varia- tion across phenotypically pure （only one male phenotype present） vs. mixed （both phenotypes present） populations revealed ge- netic distinction between phenotypes in phenotypically-pure populations, but no distinctionin phenotypically-mixed populations. The difference in patterns of genetic differentiation and mating across geographic locations suggests a complex network of fac- tors contributing to the outcome of sexual selection .

关键词： Male polymorphism Assortative mating Speciation Heritability Schizocosa

Research for effective social work practice Judy L. Krysik, Jerry finn.

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