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微型计算机 1994年第2期14卷 69-71页

作者： stapf.,C 闵珍晖

Plants as concept generators for biomimetic light-weight structures with variable stiffness and self-repair mechanisms

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Journal of Bionic Engineering 2004年第4期1卷 199-205页

作者： Thomas Speck Tom Masselter Bettina Prim Olga Speck Rolf Luchsinger siegfried Fink KompetenznetzBiomimetik der Universit tFreiburg Sch nzlestr.1 D179104 Freiburg Germany Botanischer Garten der Universit t Freiburg Sch nzlestr.1D179104 FreiburgGermany Prospective conceptsag Flughofstr.41 CH18152 Glattbrugg Switzerland Institut fur Forsfbotanik und Baumphysiologie der UniversittFreiburg Sch nzlest:1D179104 FreiburgGemmany

Plants possess many structural and functional properties that have a high potential to serve as concept generators for the production of biomimetic technical materials and structures. We present data on two features of plants (variable stiffness due to pressure changes in cellular structures and rapid self-repair functions) that may be used as models for biomimetic projects.

关键词： bionics biomimetics self-repair pneumatic structures Tensairity Aristolochia

The neuroprotective role of Wnt signaling in the retina

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Neural Regeneration Research 2021年第8期16卷 1524-1528页

作者： Stefan Kassumeh Gregor R.Weber Matthias Nobl siegfried G.Priglinger Andreas Ohlmann Department of Ophthalmology University HospitalLMU MunichMathildenstrasse 880336 MunichGermany

The canonical Wnt/β-catenin signaling pathway has been shown to play a major role during embryonic development and maturation of the central nervous system including the retina. It has a significant impact on retinal vessel formation and maturation, as well as on the establishment of synaptic structures and neuronal function in the central nervous system. Mutations in components of the Wnt/β-catenin signaling cascade may lead to severe retinal diseases, while dysregulation of Wnt signaling can contribute to disease progression. Apart from the angiogenic role of Wnt/β-catenin signaling, research in the last decades leads to the theory of a protective effect of Wnt/β-catenin signaling on damaged neurons. In this review, we focus on the neuroprotective properties of the Wnt/β-catenin pathway as well as its downstream signaling in the retina.

关键词： apoptosis β-catenin leukemia inhibitory factor Müller cells neurodegeneration neuroprotection Norrin photoreceptors retina retinal ganglion cells Wnt

Self-diffusion coefficients of organic solvents in linear and branched high density polyethylene particles measured by PFG NMR

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Chinese Chemical Letters 2008年第1期19卷 110-114页

作者： Xiao Wei Yan Xiao Hong Ren siegfried Stap Jing Dai Wang Yong Rong Yang Department of Chemical Engineering Zhejiang University Hangzhou 310027 China FG Technische Physik ll/Polymerphysik Fakultat fiir Mathematik und Naturwissenschaften Technische Universitiit Ilmenau Postfach 100565 D-98684 Ilmenau Germany Institut fiir Technische Chemie und Makromolekulare Chemie RWTH Aachen University Worringerweg 1 D-52056 Aachen Germany

Pulsed field gradient nuclear magnetic resonance （PFG NMR） has been performed to study the diffusion of organic solvents into semicrystalline polyethylene particles. Self-diffusion coefficients in different domains of the sample can be extracted through a bi- exponential fit to the echo intensity attenuation, which allows the precise determination of the tortuosity of the polyethylene particles. Further exploration comes from the measurements with branched polyethylene particles and it was found that the diffusion in polymer phase contributed significantly to the slow component of the exponential decay curve. 2007 Jing Dai Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Self-diffusion coefficients Pulsed field gradient NMR Tortuosity Polyethylene particle

Vapor transport growth of MoS2 nucleated on SiO2 patterns and graphene flakes

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Nano Research 2016年第11期9卷 3504-3514页

作者： Toma Stoica Mihai Stoica Martial Duchamp Andreas Tiedemann siegfried Mantl Detlev Orutzmacher Dan Buca Beata E. Kardynal Peter Grunberg Institute 9 (PGI 9) andJARA-Fundamentals of Future Information Technologies Forschungszentrum Julich Julich 52425 Germany National Institute of Materials Physics Magurele Bucharest 077125 Romania Institute of Physical Chemistry 'llie Murgulescu' of the Romanian Academy Bucharest 060021 Romania Peter Grunberg Institute 5 (PGI 5) and JARA-Fundamentals of Future Information Technologies Forschungszentrum Julich Julich 52425 Germany

Vapor transport growth of atomically thin MoS2 layers on patterned substrates is investigated, as it is a step towards the self-aligned growth and formation of heterojunctions, which could be useful in future applications. Enhanced formation of MoS2 flakes at the pattern edges is observed on both the substrates examined, namely, patterned thermal SiO2 on Si（100） and graphene flakes on SiO2. The diffusion driven growth leads to the formation of MoS2 monolayers （MLs） with sizes of tens of micrometers around the edges of SiO2 patterns. The growth mode and the optical quality of the MoS2 flakes can be controlled by varying the substrate temperature. Besides the lateral growth, 3R-type pyramids are obtained on prolonging the growth. Lateral MoS2-graphene heterostructures are obtained by using graphene flakes on SiO2 as a substrate.

关键词： MoS2 localized nucleation andgrowth graphene two-dimensional (2D)heterostructures

Interaction of Navigation with Minimal Access Surgery

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Surgical Science 2012年第6期3卷 295-306页

作者： siegfried Beller Surgical Clinic I Kliniken Miltenberg-Erlenbach GmbH Erlenbach am Main Germany

Minimal access surgery (MAS) includes conventional minimally invasive laparoscopic and thoracoscopic surgery, single incision laparoscopic surgery (SILS) and natural orifice transluminal endoscopic surgery (NOTES). An end of the evolution of MAS is not foreseeable, but there are still limitations. In the most common fields of intestinal surgery (cholecystectomy, appendectomy, colo-rectal resection) limitations of MAS shook dogma for surgical strategy and procedure. Automation units and telesurgical systems try to assist the surgical action. Remaining limitations are caused by lack of tactile sense and spatial awareness. With expanding application of minimal access technique in surgery the need for navigation assistance will increase. Future expansion is basically reliant on the feasibility of navigated surgery. Navigation must respect the problems of organ shift and realise continuous localisation of the surgical target as well as spatial orientation of surgical instruments and camera view.

关键词： Minimal Access Surgery Navigation

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DIE NACHT IM HOTEL

德语学习 2011年第2期 4-9,4页

作者： siegfried Lenz

Der Nachtportier strich mit seinen abgebissenen Fingerkuppen ber eine Kladde,hob bedauernd die Schultern und drehte seinen Krper zur linken Seite,wobei sich der Stoff seiner Uniform gefhrlich unter dem Armspannte.

关键词：《DIE NACHE IM HOTEL》德语学习学习方法阅读

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Journal of Geriatric Cardiology 2017年第10期14卷 632-638页

作者： Aydin Huseynov Ibrahim El-battrawy Uzair Ansari Katja Schramm Xiaobo Zhou siegfried Lang Martin Borggrefe Ibrahim Akin The First Department of Medicine Faculty of Medicine Mannheim University Medical Centre Mannheim (UMM) University of Heidelberg Mannheim Germany

Background Takotsubo syndrome （TS） is an important cardiac disease that affects predominantly postmenopausal women. This study was conducted to determine the impact of age on the short- and long-term outcome of TS patients. Methods ＆ Results The data from a collective of 114 TS patients with a mean follow-up of 1591 ：E 1079 days was retrospectively analysed. The study population was divided into two groups （≤ 65 and 〉 65 years） so as to evaluate the impact of age on the short- and long-term mortality of TS patients. In-hospital eventslike life-threatening arrhythmias （14.58% vs. 9.09%; P = 0.036）, need for mechanical respiratory support （41.66% vs. 28.78%; P = 0.15） as well as inotropic agent use （22.91% vs. 15.15%; P = 0.29）, although not reaching the statistical cut-of, tended to occur more often in the younger group. Heart failure was more common in the elderly age group （P = 0.03）. The use of multivariate analysis ruled out age as a significant marker of long term mortality （HR： 1.0; 95% CI： 0.9-1.0; P = 0.60）. Conclusions Age does not influence the clinical course of TS in terms of the short- as well as long-term outcome. The study revealed a higher incidence of life threatening arrhythmias in the younger patient age-group and a higher incidence of heart failure among the older group of patients.

关键词： Age Cardiovascular risk Mortality Takotsubo syndrome

弹性基底上受非均匀荷载加劲板的局部屈曲特性

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交通运输工程学报 2017年第1期17卷 36-44页

作者：张宁刘永健李慧 STIEMER siegfried F 西北农林科技大学水利与建筑工程学院陕西杨凌712100 长安大学陕西省公路桥梁与隧道重点实验室陕西西安710064 不列颠哥伦比亚大学土木工程系哥伦比亚温哥华V6T 1Z4

针对弹性基底上板的局部稳定问题,应用能量法推导了非均匀荷载作用下矩形加劲板的局部屈曲非线性特征方程,建立了考虑弹性基底接触和纵向加劲肋作用的屈曲板迦辽金表达式;基于牛顿迭代法,建立了局部屈曲的非线性特征方程的增量迭代格式... 详细信息

针对弹性基底上板的局部稳定问题,应用能量法推导了非均匀荷载作用下矩形加劲板的局部屈曲非线性特征方程,建立了考虑弹性基底接触和纵向加劲肋作用的屈曲板迦辽金表达式;基于牛顿迭代法,建立了局部屈曲的非线性特征方程的增量迭代格式与屈曲荷载特征值的附加迭代方程。分析结果表明:屈曲系数计算结果与有限元分析结果误差小于2%,并且避免了有限元模拟的接触分析过程,计算效率较高;当荷载梯度为1时,设置加劲肋的偏心构件的局部稳定性明显增强,临界屈曲系数增加到51.1,是普通板件的2.5倍;加劲板件的纵向鼓曲波的长宽比约为0.6,鼓曲波纵向排列相对密集,而普通板件每个鼓曲波的长宽比约为1.0;在不增加加劲肋材料用量的前提下,设置纵向加劲肋的最优位置为距离板件受压侧边缘的2/5板宽处,临界屈曲系数增加为78.9,是普通板件的4倍;加劲肋的设置可将矩形钢管混凝土壁板的宽厚比增加到172,将界限值提高2倍以上。可见,在矩形钢管混凝土管壁设置纵向加劲肋能够有效提高偏压作用下管壁的局部稳定性,改善矩形钢管混凝土的截面尺寸。

关键词：桥梁工程钢管混凝土迦辽金法屈曲系数加劲肋弹性基底非均匀受压

When Lotus Leaves Prevent Metal from Melting一Biomimetic Surfaces for High Temperature Applications

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Journal of Bionic Engineering 2019年第2期16卷 281-290页

作者： Wilfried Konrad Jorg Adam siegfried Konietzko Christoph Neinhuis Technical University of Dresden Institute of BotanyZellescher Weg 20bD-01062 Dresden Germany VDEh-Betriebsforschungsinstitut GmbH Sohnstrafie 6540237 DusseldorfGermany Lebronze Alloys Germany-Hundt&Weber GmbH、Birlenbacher Strafie 1 57078 SiegenGermany CON-RE A Consulting&RealizationGrafschafter Strafie 1347199 DuisburgGermany

Functional properties of biological surfaces have gained increasing interest in the last two decades,especially with regard to wetting and ***,biological surfaces of arthropods(Collembola)and plants(sacred Lotus)served as models for the principle design of high temperature resistant surfaces used in blast furnaces to prevent tuyeres from *** are double-walled,watercooled pipes supplying the blast furnace with hot air to keep the reduction and melting process *** failure is mainly caused by melting of the wall after direct contact with liquid iron,resulting in the partial shut down of the blast furnace and huge energy *** a new approach to avoid tuyere failure we developed a new type of tuyere surface with(i)defined cone shaped indentations and(ii)a heat resistant zirconium/corundum coating with"ferrophobic”properties *** forms with liquid iron of 1500°C a contact angle exceeding 130°.Theoretical considerations indicate that liquid iron infiltrates these indentations only partially if this contact angle and the aperture angle of the cone satisfy an inequality *** heat conductivity of the remaining gas trapped inside the cones is by five orders of magnitude lower than in copper,the overall heat flow into the tuyere is substantially reduced and the outer walls are much less prone to melting.

关键词： tuyere blast furnace biomimetics liquid iron heat flow