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MAPPING THE DAMAGED ZONE AROUND THE CRACK TIP IN HIGH DENSITY POLYETHYLENE WITH SYNCHROTRON MICROFOCUS SMALL ANGLE X-RAY SCATTERING TECHNIQUE

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Chinese Journal of Polymer Science 2010年第2期28卷 165-170页

作者： Hans-Friedrich Enderle Dieter Lilge Stephan v.Roth Rainer Gehrke jens Rieger 门永锋 Basell Polyolefine GmbH R&D65926 FrankfurtGermany HASYLAB am DESY Notkestr.8522607 HamburgGermany BASF SE Polymer Research67056 LudwigshafenGermany State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The structural changes around a crack tip in a high density polyethylene were investigated by means of scanning synchrotron microfocus small-angle X-ray scattering technique. The scattering data confirm the process of craze structure development near a crack tip based on the evolution of voids. In addition, it was found that the main stress in the plastic zone near a crack tip exhibited a gradient distribution with respect to its strength and direction. The whole damaged area showed a strain distribution indicating a flow behavior toward the crack tip.

关键词： High density polyethylene Microfocus SAXS Crack tip voids.

A New Species of Japalura(Squamata, Agamidae) from the Nu River valley in Southern Hengduan Mountains, Yunnan, China

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Asian Herpetological Research 2017年第2期18卷 86-95页

作者： Dingqi RAO jens v.vINDUM Xiaohui MA Mingxia FU Jeffery A.WILKINSON Kunming Institute of Zoology Chinese Academy of Sciences Department of Herpetology California Academy of Sciences

A population of Japalura from Yunnan Province, China, previously assigned to Japalura splendida, is described as a new species. The new species has been recorded between 1 138–2 500 m in the Nu River drainage between the towns of Liuku and Binzhongluo, and on the lower western slopes of the Nushan and eastern slopes of the Goaligongshan. The new species can be distinguished from other species of Japalura, except J. dymondi, by the following combination of characters： exposed tympani, prominent dorso-lateral stripes, and small gular scales. It is very similar with but differs from J. dymondi by having smooth or feebly keeled dorsal head scales, three relatively enlarged spines on either side of the post-occiput area, strongly keeled and mucronate scales on occiput area and within the lateral stripes, back of arm and leg green, higher number of dorsal-ridge scales（DS） and fourth toe subdigital scales（T4S）. A principal component analysis of body measurements of adult male specimens of the new species and J. dymondi showed principal component 1 loading highest for upper arm length, fourth toe length and snout to eye length and principal component 2 loading highest for head width, head length and fourth toe length.

关键词： Agamidae Japalura sp.nov. Goaligongshan Mountain Nujiang River valley Hengduan Mountains Yunnan China

Environmental analysis of innovative sustainable composites with potential use in aviation sector -A life cycle assessment review

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Science China(Technological Sciences) 2017年第9期60卷 1301-1317页

作者： BACHMANN jens HIDALGO Carme RICOUT Stephanie Deutsches Zentrum fiir Lufi- und Raumfahrt e. v. (German Aerospace Centre) Institute of Composite Structures and Adaptive Systems-Department of Multifunctional Materials Lilienthalplatz 7 38108 Braunsehweig Germany Leitat Technological Center C/Innovacio 2 08225 Terrassa Spain Airbus Group Innovations Fuels and Environment 12 rue Pasteur 92152 Suresnes France

The forecast of growing air transport in the upcoming decades faces the challenge of an increasing environmental *** industry is working on promising technologies to mitigate this environmental *** design is a strong lever to lower the fuel consumption and,consequently,with it the emissions of *** performance composites are a key technology to help achieve these aims thanks to their favourable combination of mechanical properties and low weight in primary ***,mainly synthetic materials such as petrol based carbon fibres and epoxy resins are used nowadays to produce composite in *** materials like bio-based fibres and resin systems offer potential environmental ***,they have not found their way into aviation,*** reasons are reduced mechanical properties and,especially for the use of natural fibres,their *** of these shortcomings are under *** the application of bio-based and recycled materials in certain areas of the aircraft could be possible in the *** examples for applications are furnishings and secondary *** motivation for this paper is to give an overview of potential environmental properties by using such eco-materials in *** cycle assessment(LCA) is a tool to calculate environmental impacts during all life stages of a *** main focus is laid on the bio-fibres flax and ramie,recycled carbon fibres and bio-based thermoset resin *** an overview of environmental aspects of existing composite materials used in aviation is ***,a lack of LCA results for the substitution of synthetic materials by bio-based/recycled composite materials in aviation applications has been ***,available information from other transport areas,such as automotive,has been *** detailed LCA data for eco-composite materials and technologies to improve their properties is import

关键词： aviation composite natural fibre recycled carbon fibre bio-resin cabin interior secondary structure,fife cycle assessment (LCA)

Investigations and prospects of Fabry-Perot antennas:a review

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Journal of Systems Engineering and Electronics 2021年第4期32卷 731-747页

作者： LIU Zhiming BORNEMANN jens LIU Shaobin KONG Xiangkun Department of Electrical and Computer Engineering University of VictoriaVictoria V8W 2Y2Canada College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Fabry-Perot(FP)antennas have characteristics of planar structures combined with high gain,and they have been widely used in wireless *** the progress of ongoing research,FP antennas have achieved various capabilities,but many of them are still under development,such as lowprofile,wideband,circular polarization,multi-band,low-radar cross section(RCS)and reconfigurable *** paper discusses the theoretical analysis methods and research progress of FP antennas,and explains the realization methods of different features of FP *** order to indicate different technologies for realizing various capabilities,the key technologies and features of some of the latest designs are ***,the research situation and prospects of FP antennas are summarized to guide their research directions in the future.

关键词： Fabry-Perot(FP)antenna partially reflective surface research situation research direction

Novel Traveling Wave Sandwich Piezoelectric Transducer with Single Phase Drive:Theoretical Modeling,Experimental validation,and Application Investigation

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 206-225页

作者： Liang Wang Fushi Bai viktor Hofmann Jiamei Jin jens Twiefel State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Institute of Dynamics and vibration Research Leibniz University Hannover30167 HannoverGermany School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072ShaanxiChina

Most of traditional traveling wave piezoelectric transducers are driven by two phase different excitation signals,leading to a complex control system and seriously limiting their applications in *** overcome these issues,a novel traveling wave sandwich piezoelectric transducer with a single-phase drive is proposed in this *** waves are produced in two driving rings of the transducer while the longitudinal vibration is excited in its sandwich composite beam,due to the coupling property of the combined *** results in the production of elliptical motions in the two driving rings to achieve the drive *** analytical model is firstly developed using the transfer matrix method to analyze the dynamic behavior of the proposed *** vibration characteristics are measured and compared with computational results to validate the effectiveness of the proposed analytical ***,the driving concept of the transducer is investigated by computing the motion trajectory of surface points of the driving ring and the quality of traveling wave of the driving ***,application example investigations on the driving effect of the proposed transducer are carried out by constructing and assembling a tracked mobile *** results indicated that 1)the assembled tracked mobile system moved in the driving frequency of 19410 Hz corresponding to its maximum mean velocity through frequency sensitivity experiments;2)motion characteristic and traction performance measurements of the system prototype presented its maximum mean velocity with 59 mm/s and its maximum stalling traction force with 1.65 N,at the excitation voltage of 500 v_(RMS).These experimental results demonstrate the feasibility of the proposed traveling wave sandwich piezoelectric transducer.

关键词： Traveling wave Sandwich piezoelectric transducer Single phase excitation Transfer matrix method Ultrasonic motor

Social and Ecological Constraints on Decision Making by Transhumant Pastoralists: A Case Study from the Moroccan Atlas Mountains

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Journal of Mountain Science 2012年第3期9卷 307-321页

作者： Zakia AKASBI jens OLDELAND Jürgen DENGLER Manfred FINCKH Biodiversity Evolution and Ecology of PlantsBiocentre Klein Flottbek and Botanical GardenUniversity of HamburgOhnhorststr.1822609 HamburgGermany Institut Agronomique et vétérinaire Hassan II B.P.6202 les instituts10000-RabatMorocco

Transhumant pastoralism is an important activity in southern Morocco. Migration pattern of transhumant pastoralists can be affected by physical factors (e.g. droughts and diseases) or socioeconomic factors (e.g. schooling options for children and migration costs). We studied the spatio-temporal rangeland usage of the three tribes Ait Mgoun, Ait Zekri, and Ait Toumert in the south-central Atlas region with a two-fold approach. First, we tracked the migration movements of one representative transhumant herd using the Advanced Research and Global Observation Satellite (ARGOS) collars, which record coordinates from satellite signals. Second, we interviewed herders to obtain information about general grazing practices of the respective tribe and to gain more direct information on motivations underlying decisions. For each tribe we observed small-, medium- and large-scale movements. We found that the most important drivers of migration decisions were seasonal fodder availability and weather conditions in combination with herd-specific risk and cost assessment, as well as personal factors. In conclusion, general migration patterns vary in time, both between and within the tribes, but according to a regulatory framework. Moreover, it appears that both the customary rules and its flexible adaptation to physical constraints are generally beneficial in terms of conservation of the arid and semiarid rangeland resources.

关键词： Ait Mgoun Ait Zekri Ait Toumert ARGOS Goat grazing High Atlas Jebel Saghro Migration pattern Rangeland Small ruminant Transhumance

Low-FODMAP diet reduces irritable bowel symptoms in patients with inflammatory bowel disease

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World Journal of Gastroenterology 2017年第18期23卷 3356-3366页

作者： Natalia Pedersen Dorit vedel Ankersen Maria Felding Henrik Wachmann Zsuzsanna végh Line Molzen Johan Burisch jens Rikardt Andersen Pia Munkholm Department of Gastroenterology Slagelse Hospital Gastroenterology Unit North Zealand Hospital Department of Nutrition Exercise and SportsUniversity of Copenhagen Department of Statistics First Department of Medicine Semmelweis University

To investigate the effect of a low-FODMAP diet on irritable bowel syndrome (IBS)-like symptoms in patients with inflammatory bowel disease (IBD).METHODSThis was a randomised controlled open-label trial of patients with IBD in remission or with mild-to-moderate disease and coexisting IBS-like symptoms (Rome III) randomly assigned to a Low-FODMAP diet (LFD) or a normal diet (ND) for 6 wk between June 2012 and December 2013. Patients completed the IBS symptom severity system (IBS-SSS) and short IBD quality of life questionnaire (SIBDQ) at weeks 0 and 6. The primary end-point was response rates (at least 50-point reduction) in IBS-SSS at week 6 between groups; secondary end-point was the impact on quality of ***-nine patients, 67 (75%) women, median age 40, range 20-70 years were randomised: 44 to LFD group and 45 to ND, from which 78 patients completed the study period and were included in the final analysis (37 LFD and 41 ND). There was a significantly larger proportion of responders in the LFD group (n = 30, 81%) than in the ND group (n = 19, 46%); (OR = 5.30; 95%CI: 1.81-15.55, P ve study, a low-FODMAP diet reduced IBS-like symptoms and increased quality of life in patients with IBD in remission.

关键词： Inflammatory bowel disease Web-based management Irritable bowel syndrome Low-FODMAP diet

i2dash:Creation of Flexible,Interactive,and Web-based Dashboards for visualization of Omics Data

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Genomics, Proteomics & Bioinformatics 2022年第3期20卷 568-577页

作者： Arsenij Ustjanzew jens Preussner Mette Bentsen Carsten Kuenne Mario Looso Max Planck Institute for Heart and Lung Research Bioinformatics UnitD-61231 Bad NauheimGermany

Data visualization and interactive data exploration are important aspects of illustrating complex concepts and results from analyses of omics data.A suitable visualization has to be intuitive and ***-based dashboards have become popular tools for the arrangement,consolidation,and display of such ***,the combination of automated data processing pipelines handling omics data and dynamically generated,interactive dashboards is poorly ***,we present i2dash,an R package intended to encapsulate functionality for the programmatic creation of customized *** supports interactive and responsive(linked)visualizations across a set of predefined graphical layouts.i2dash addresses the needs of data analysts/software developers for a tool that is compatible and attachable to any R-based analysis pipeline,thereby fostering the separation of data visualization on one hand and data analysis tasks on the other *** addition,the generic design of i2dash enables the development of modular extensions for specific *** a proof of principle,we provide an extension of i2dash optimized for single-cell RNA sequencing analysis,supporting the creation of dashboards for the visualization needs of such *** with these features,i2dash is suitable for extensive use in large-scale sequencing/bioinformatics *** this line,we provide i2dash as a containerized solution,enabling a straightforward large-scale deployment and sharing of dashboards using cloud services.i2dash is freely available via the R package archive CRAN(https://***/package=i2dash).

关键词： Data visualization Dashboard Cloud Data analysis Automation

Chronic intestinal ischemia and splanchnic blood-flow:Reference values and correlation with body-composition

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World Journal of Gastroenterology 2013年第6期19卷 882-888页

作者： Helle Damgaard Zacho jens Henrik Henriksen Jan Abrahamsen Department of Clinical Physiology Viborg Regional Hospital Department of Clinical Physiology Hvidovre HospitalUniversity of Copenhagen

AIM:To determine the splanchnic blood flow and oxygen uptake in healthy-subjects and patients and to relate the findings to ***:The total splanchnic blood flow (SBF) and oxygen uptake (SO2U) were measured in 20 healthy volunteers (10 women) and 29 patients with suspected chronic intestinal ischemia (15 women),age 40-85 years,prior to and after a standard *** method is based on the Fick principle using the continuous infusion of an indicator (99mTechnetium-labelled mebrofenin) and catheterization of an artery and the hepatic *** angiography of the intestinal arteries was performed during the same investigation.A whole-body dual-energy x-ray absorptiometry scan was performedin healthy volunteers to determine body ***:Angiography revealed no atherosclerotic lesions in the intestinal *** mean baseline SBF was 1087mL/min (731-1390),and this value increased significantly to 1787 mL/min after the meal in healthy volunteers (Pvolunteers and patients was 50.7mL/min and 48.0mL/min,respectively,and these values increased to 77.5 mL/min and 75mL/min postprandially,*** baseline and postprandial SO2U were directly related to lean body *** and sex exerted no impact on ***:A direct correlation between body weight and the postprandial increase in SBF was *** effect of body weight should be considered in the diagnosis of chronic intestinal ischemia.

关键词： Splanchnic circulation Postprandial period Body composition Mesenteric vascular occlusion Middle aged