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Influence of External Plasticization on Rheological and Thermal Properties of Cellulose Acetate with Respect to Its Foamability

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材料科学与工程（中英文A版） 2012年第2期2卷 152-163页

作者： Stefan Zepnik stephan Kabasci Hans-Joachim Radusch and Thomas Wodke Fraunhofer Institute for Environmental Safety and Energy UMSICHT Oberhausen D-46047 Germany Center of Engineering Sciences Martin Luther University Halle-Wittenberg Halle/Saale D-06099 Germany

Cellulose acetate needs appropriate plasticization for proper processing and achieving suitable properties. At thermoplastic foam production via melt technologies rheological and thermal properties are key factors for the generation of high quality products. Therefore, the influence of external plasticization on rheological and thermal properties of cellulose acetate (CA) was investigated. different types of plasticizers were used for this study. The influence on the properties depends largely on the type of plasticizer and its compatibility with CA. Glass transition temperature of CA decreased significantly with increasing plasticizer content whereas thermal stability of CA remains almost constant. Melt processing is enhanced due to broadening of the thermoplastic window. The rheological behavior of CA was significantly improved by increasing plasticizer content. Melt flow increases while melt viscosity decreases with an increase in plasticizer content. Also melt strength and drawability were considerably improved. As expected, plasticizer performance is closely linked to the miscibility and mutual compatibility of the plasticizer with CA.

关键词：醋酸纤维素流变性能热性能塑化起泡性玻璃化转变温度增塑剂塑料泡沫

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面向3d呈现的有损和无损混合深度视频编码

光电子．激光 2017年第2期28卷 211-216页

作者：刘云鹏 stephan Beck 王仁芳王阳郑文 Bemd Froehlich 浙江万里学院浙江宁波315100 包豪斯大学德国魏玛99401

针对多个深度视频流提出实时的压缩方法和评估方案,采用一种有损无损混合的编码方法,可以在图像质量和压缩率之间提供一种有效的平衡控制。行程编码(RLE)用于无损压缩,用来保存深度图像素的高位;像素低10bits保存在YUV图像的Y通道,直接... 详细信息

针对多个深度视频流提出实时的压缩方法和评估方案,采用一种有损无损混合的编码方法,可以在图像质量和压缩率之间提供一种有效的平衡控制。行程编码(RLE)用于无损压缩,用来保存深度图像素的高位;像素低10bits保存在YUV图像的Y通道,直接使用×264编码。实验表明,所提方法可以在平均时间小于12ms的前提下同时编解码多个深度图。在实时传输中,通过动态调节质量控制级别,可以获取4∶1到20∶1的压缩率。在压缩率10∶1的情况下,主观解码3d重构效果与原始图几乎完全一致。

关键词：编码压缩深度视频 3d

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儿科PET/CT的操作和剂量学

中华核医学与分子影像杂志 2019年第5期39卷 314-320页

作者：王宽垠(译) 刘振(译) 兰晓莉(审校) Frederic H. Fahey Alison Goodkind Robert d. Macdougall Leah Oberg Sonja I.Ziniel Richard Cappock Michael J. Callahan Neha Kwatra S. Ted Treves stephan d. Voss 华中科技大学同济医学院附属协和医院核医学科武汉430022 division of Nuclear Medicine and Molecular Imaging Department of Radiology Boston Children′s Hospital Boston Massachusetts department of Radiology Harvard Medical School Boston Massachusetts Section of Pediatric Hospital Medicine Department of Pediatrics University of Colorado School of Medicine and Children′s Hospital Colorado Aurora Colorado department of Radiology Brigham and Women′s Hospital Boston Massachusetts

在儿科PET/CT诊疗领域,迄今还没有统一的CT扫描方法的指南。考虑到儿童更易受电离辐射的影响,在最短时间内和最小暴露剂量条件下提供具有诊断质量的图像十分必要。该文描述了CT辐射剂量测定以及儿童PET/CT采集的基本要点。根据对北美19... 详细信息

在儿科PET/CT诊疗领域,迄今还没有统一的CT扫描方法的指南。考虑到儿童更易受电离辐射的影响,在最短时间内和最小暴露剂量条件下提供具有诊断质量的图像十分必要。该文描述了CT辐射剂量测定以及儿童PET/CT采集的基本要点。根据对北美19所儿科PET/CT机构的调查,描述了儿科PET/CT技术的多样性。调查结果表明,尽管大多数机构采用自动管电流调制,但在实际应用中各机构间仍存在2~3倍的差异,这说明需要统一的指南。该文介绍了作者所在机构研发的多序列PET/CT采集技术,此技术可以兼顾在重要部位视野内获得有诊断质量的CT图像,以及在其余部位应用低辐射技术进行显像。这种方法使患者所受辐射剂量减少,同时将PET和具有诊断质量的CT集成在单次采集中。儿科PET/CT的标准化在保证适中水平的图像质量的同时,为患者提供了减少辐射剂量的机会。

关键词：儿科辐射剂量测定 PET/CT 计算机体层摄影术

ConGrap -Contour detection Based on Gradient Map of Images

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Computer Technology and Application 2011年第8期2卷 628-637页

作者： Frank Nagl Konrad Kolzer Paul Grimm Tobias Bindel stephan Rothe Applied Computer Science Fulda University of Applied Sciences Fulda D-36039 Germany Applied Computer Science Erfurt University of Applied Sciences Erfurt D-99085 Germany

In this paper, the authors present ConGrap, a novel contour detector for finding closed contours with semantic connections. Based on gradient-based edge detection, a Gradient Map is generated to store the orientation of every edge pixel. Using the edge image and the generated Gradient Map, ConGrap separates the image into semantic parts and objects. Each edge pixel is mapped to a contour by a three-stage hierarchical analysis of neighbored pixels and ensures the closing of contours. A final post-process of ConGrap extracts the contour borderlines and merges them, if they semantically relate to each other. In contrast to common edge and contour detections, ConGrap not only produces an edge image, but also provides additional information (e. g., the borderline pixel coordinates the bounding box, etc.) for every contour. Additionally, the resulting contour image provides closed contours without discontinuities and merged regions with semantic connections. Consequently, the ConGrap contour image can be seen as an enhanced edge image as well as a kind of segmentation and object recognition.

关键词：轮廓界线边缘检测影像地图梯度边缘图像边缘像素层次分析轮廓检测

Argon-seeded plasma exposure and oxidation performance of tungsten-chromium-yttrium smart alloys

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Tungsten 2019年第2期1卷 159-168页

作者： Janina Schmitz Andrey M.Litnovsky Felix Klein Xiaoyue Tan Uwe Breuer Marcin Rasinski stephan Ertmer Arkadi Kreter Jesus Gonzalez-Julian Martin Bram Jan Willem Coenen Christian Linsmeier Forschungszentrum Juelich GmbH Institut fuer Energie-und Klimaforschung52425 JuelichGermany department of Applied Physics Ghent University9000 GhentBelgium School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Forschungszentrum Juelich GmbH Institut fuer Engineering und Analytik52425 JuelichGermany

Tungsten-chromium-yttrium(WCrY)smart alloys are foreseen as the first wall material for future fusion devices such as demonstration Power Plant(dEMO).While suppressing W oxidation during accidental conditions,they should behave like pure W during plasma operation due to preferential sputtering of the lighter alloying elements Cr,Y,and W enrichment of the *** this paper,the erosion performance of WCrY and W samples simultaneously exposed to deuterium(d)plasma with the addition of 1%of the projectile ions being argon(Ar)ions at an ion energy of 120 eV is *** reference to the previous experiments at 120 eV in pure d plasma,the erosion for both WCrY and W is enhanced by a factor of~*** Ar to the d plasma suppresses significant W enrichment previously found for pure d *** investigate the impact of the plasma exposure onto the oxidation performance,plasma-exposed and non-exposed reference samples were oxidised in a dry *** show,on the one hand,that the oxida-tion suppression of WCrY in comparison to pure W is preserved during the plasma *** the other hand,it becomes evident that edge effects imposed by the geometry of the samples used in plasma experiments play a significant role for the oxidation behaviour.

关键词： Tungsten-based alloys Plasma-facing material Smart alloys dEMO

Thermal Behavior of Externally driven Spindle: Experimental Study and Modelling

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Engineering（科研） 2015年第2期7卷 73-92页

作者： Christian Brecher Yair Shneor stephan Neus Kolja Bakarinow Marcel Fey RWTH Aachen University Laboratory for Machine Tools and Production Engineering Chair of Machine Tools Aachen Germany CAMT Center for Advanced Manufacturing Technologies Rotem Industries Rotem Industrial Park Mishor Yamin D.N. Arava Israel

This paper focuses on model development for computer analysis of the thermal behavior of an externally driven spindle. The aim of the developed model is to enable efficient quantitative estimation of the thermal characteristics of the main spindle unit in an early stage of the development process. The presented work includes an experimental validation of the simulation model using a custom-built test rig. Specifically, the effects of the heat generated in the bearings and the heat flux from the bearing to the adjacent spindle system elements are investigated. Simulation and experimental results are compared and demonstrate good accordance. The proposed model is a useful, efficient and validated tool for quantitative simulation of thermal behavior of a main spindle system.

关键词： Machine Tool Thermal Behavior Heat Transfer Spindle Modelling

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拟南芥多磷酸肌醇6-/3-激酶功能研究

拟南芥多磷酸肌醇6-/3-激酶功能研究

Human iPSC-derived iMSCs improve bone regeneration in mini-pigs

中国植物学会七十周年年会

作者：夏惠君 Charles BREARLEY stephan ELGE Bernd MUELLER-ROEBER 武汉大学生命科学院植物发育生物学教育部重点实验室 School of Biological Sciences University of East AngiaNorwich NR4 7TJUnited Kingdom Institute of Biochemistry and Biology University of Potsdam Karl-Liebknecht-Strasse 25 Haus 20 D-14476 Golm/Potsdam Germany

1,4,5-三磷酸肌醇3-激酶,又称多磷酸肌醇激酶(Ipk),在动物细胞的信号传导中起重要的作用。但是,它们在植物细胞中的功能尚不清楚。我们首次从拟南芥中克隆出该基因的cdNA(AtIpk2β)。该基因编码一个33 kda的蛋白,该蛋白与动物和酵母细...

1,4,5-三磷酸肌醇3-激酶,又称多磷酸肌醇激酶(Ipk),在动物细胞的信号传导中起重要的作用。但是,它们在植物细胞中的功能尚不清楚。我们首次从拟南芥中克隆出该基因的cdNA(AtIpk2β)。该基因编码一个33 kda的蛋白,该蛋白与动物和酵母细胞中的Ipk蛋白只有很低的同源性(约25%氨基酸相同),并且缺少钙调蛋白结合位点。由大肠杆菌表达得到的重组蛋

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Bone Research 2019年第4期7卷 399-409页

作者： Pascal Jungbluth Lucas-Sebastian Spitzhorn Jan Grassmann stephan Tanner david Latz Md Shaifur Rahman Martina Bohndorf Wasco Wruck Martin Sager Vera Grotheer Patric Kropil Mohssen Hakimi Joachim Windolf Johannes Schneppendahl James Adjaye department of Trauma and Hand Surgery Heinrich Heine University Hospital DüsseldorfMoorenstr.540225 DüsseldorfGermany Institute for Stem Cell Research and Regenerative Medicine Medical FacultyHeinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany Animal Research Institute Heinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany department of diagnostic and Interventional Radiology Medical FacultyHeinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany Vivantes Klinikum Am Urban Dieffenbachstraβe 110967 BerlinGermany

Autologous bone marrow concentrate(BMC)and mesenchymal stem cells(MSCs)have beneficial effects on the healing of bone *** address the shortcomings associated with the use of primary MSCs,induced pluripotent stem cell(iPSC)-derived MSCs(iMSCs)have been proposed as an *** aim of this study was to investigate the bone regeneration potential of human iMSCs combined with calcium phosphate granules(CPG)in critical-size defects in the proximal tibias of mini-pigs in the early phase of bone healing compared to that of a previously reported autograft treatment and treatment with a composite made of either a combination of autologous BMC and CPG or CPG *** were derived from iPSCs originating from human fetal foreskin fibroblasts(HFFs).They were able to differentiate into osteoblasts in vitro,express a plethora of bone morphogenic proteins(BMPs)and secrete paracrine signaling-associated cytokines such as PdGF-AA and *** and histomorphometrically,HFF-iMSC+CPG transplantation resulted in significantly better osseous consolidation than the transplantation of CPG alone and produced no significantly different outcomes compared to the transplantation of autologous BMC+CPG after 6 *** results of this translational study imply that iMSCs represent a valuable future treatment option for load-bearing bone defects in humans.

关键词： healing alone treatment

High-dose interferon-α2b induction therapy in combination with ribavirin for treatment of chronic hepatitis C in patients with non-response or relapse after interferon-a monotherapy

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World Journal of Gastroenterology 2005年第34期11卷 5342-5346页

作者： Holger G. Hass Christian Kreysel Johannes Fischinger Josef Menzel stephan Kaiser department of Gastroenterology and Hepatology University of Tuebingen Germany department of Gastroenterology Klinikum Krefeld Germany department of Gastroenterology and Hepatology University of Saarland Germany department of Gastroenterology and Hepatology University of Muenster Germany

AIM: To evaluate the daily high-dose induction therapy with interferon-α2b (IFN-α2b) in combination with ribavirin for the treatment of patients who failed with interferon monotherapy and had a relapse, based on the assumption that the viral burden would decline faster, thus increasing the likelihood of higher response rates in this diffficult-to-treat patient ***: Seventy patients were enrolled in this *** was started with 10 MU IFN-α2b daily for 3 wk,followed by IFN-α2b 5 MU/TIW in combination with ribavirin (1 000-1 200 mg/d) for 21 wk. In case of a negative HCV RNA PCR, treatment was continued until wk 48 (IFN-α2b 3 MU/TIW+1 000-1 200 mg ribavirin/daily).RESULTS: The dose of IFN-α2b or ribavirin was reduced in 16% of patients because of hematologic side effects,and treatment was discontinued in 7% of patients. An early viral response (EVR) was achieved in 60% of patients. Fifty percent of all patients achieved an end-of-treatment response (EOT) and 40% obtained a sustained viral response (SVR). Patients with no response had a significantly lower response rate than those with a former relapse (SVR 30% vs 53%; P = 0.049). Furthermore,lower response rates were observed in patients infected with genotype 1a/b than in patients with non-1-genotype (SVR 28% vs74%; P= 0.001). As a significant predictive factor for a sustained response, a rapid initial decline of HCV RNA could be identified. No patient achieving a negative HCV-RNA PCR at wk 18 or later eventually eliminated the ***: daily high-dose induction therapy with interferon-α2b is well tolerated and effective for the treatment of non-responders and relapsers, when interferon monotherapy fails. A fast decline of viral load during the first 12 wk is strongly associated with a sustained viral response.

关键词：干扰素-α2b 用药剂量病毒唑慢性丙型肝炎