检索结果-南通市图书馆

维普期刊数据库

Coated boron layers by boronization and a real-time boron coating using an impurity powder dropper in the LHD

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第8期26卷 25-31页

作者： Naoko ASHIKAWA Robert LUNSFORD Federico NESPOLI erik GILSON yaowei yU Jiansheng HU Shinichiro KADO National Institute for Fusion Science Toki 509-5292Japan Princeton Plasma Physics Laboratory Princeton NJ 08540United States of America Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Institute of Advanced Energy Kyoto UniversityKyoto 611-0011Japan

In the Large Helical Device(LHD),diborane(B2H6)is used as a standard boron source for boronization,which is assisted by helium glow *** 2019,a new Impurity Powder Dropper(IPD)system was installed and is under evaluation as a real-time wall conditioning *** the LHD,which is a large-sized heliotron device,an additional helium(He)glow discharge cleaning(GDC)after boronization was operated for a reduction in hydrogen recycling from the coated boron *** operational time of 3 h was determined by spectroscopic data during glow discharges.A flat hydrogen profile is obtained on the top surface of the coated boron on the specimen exposed to *** results suggest a reduction in hydrogen at the top surface by *** oxygen in coated boron was obtained by boronization,and the coated boron,which has boron-oxide,on the first wall by B-IPD was also *** the difference in coating areas between B2H6 boronization and B-IPD operation,it would be most effective to use the IPD and B2H6 boronization coating together for optimized wall conditioning.

关键词： boron layer oxygen impurity hydrogen recycling impurity powder dropper LHD EAST

维普期刊数据库

Application of a k-ε Model to Heat Transfer in Impinging Flows

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2004年第1期13卷 62-66页

作者： Bart Merci Chris De Langhe Koen Lodefier erik Dick Ghent University Dept.of FlowHeat and Combustion MechanicsSint-Pietersnieuwstraat 41B-9000 GentBelgiumGhent UniversityDept.of FlowHeat and Combustion MechanicsSint-Pietersnieuwstraat 41B-9000 GentBelgiumGhent UniversityDept.of FlowHeat and Combustion MechanicsSint-Pietersnieuwstraat 41B-9000 GentBelgiumGhent UniversityDept.of FlowHeat and Combustion MechanicsSint-Pietersnieuwstraat 41B-9000 GentBelgium

Local heat transfer is predicted in turbulent axisymmetric jets, impinging onto a flat plate. A non-linear k-e model is used, in which both the constitutive law for the turbulent stresses and the transport equation for the turbulent dissipation rate e have an important contribution in the improved heat transfer predictions. The shape of the Nusselt number profiles, expressing dimensionless heat transfer, as well as the stagnation point value, are well predicted for different distances between the nozzle exit and the plate. Accurate flow field predictions are the basis for good heat transfer predictions. For a fixed Reynolds number, the influence of the nozzle-plate distance is well captured. For a fixed distance, the influence of the Reynolds number is correctly reproduced. Comparisons are made to a low-Reynolds standard k-e model and the v2-f model. A thorough discussion is found in [4]. Only a summary of those results is discussed here, while some new results are also presented.

关键词： local heat transfer impinging jets non-linear k-ε model.

维普期刊数据库

Bone blood flow is influenced by muscle contractions

在线全文

学校读者我要写书评

暂无评论

Journal of Biomedical Science and Engineering 2011年第7期4卷 490-496页

作者： Jan erik Naslund Sofie Naslund erik Lundeberg Lars-Goran Lindberg Irene Lund Department of Physiology and Pharmacology Karolinska InstitutetStockholmSweden Gavle Hospital GavleSweden Department of Biomedical Engineering Linkoping UniversityLinkopingSweden

Forces acting on the skeleton could be divided into those originating from gravitational loading and those originating from muscle loading. flat bones in a non-weight-baring segment of the skeleton probably experience forces mostly generated by muscle contractions. One purpose of muscle contractions is to generate blood flow within skeletal tissues. The present study aimed to investigate the pulsatile patellar bone blood flow after low and high intensity leg extension exercises. Forty-two healthy individuals volunteered for the study. Dynamic isotonic one leg extension/flexion exercises were performed in a leg extension machine. Randomly, the exercises were performed with the left or right leg with either 10 repetition maximum (10 RM) continuously without any resting periods (high intensity muscle work), or 20 RM with a 2 second rest between contractions (low intensity muscle work). The work load, expressed in kilograms totally lifted, was identical in both legs. The pulsatile patellar blood flow was recorded continuously using a photoplethysmographic technique. Blood pressure was measured continuously during muscle work by a non-invasive method (Finapress). The patellar pulsatile bone blood flow increased significantly more after high intensity muscle work (61%) compared to the same work load performed using a lower intensity (22%), p = 0.000073. Systolic blood pressure changed equally during and after both interventions. Post-exercise bone hyperaemia appears to be correlated to the intensity of muscle contractions in the muscle compartment attached to the bone.

关键词： Bone Blood Flow Blood Pressure Photoplethysmography

High-angle deflection of metagrating-integrated laser emission for high-contrast microscopy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2023年第11期12卷 2434-2442页

作者： Mindaugas Juodėnas erik Strandberg Alexander Grabowski Johan Gustavsson HanaŠípová-Jungová Anders Larsson Mikael Käll Department of Physics Chalmers University of Technology41296 GothenburgSweden Department of Microtechnology and Nanoscience Chalmers University of Technology41296 GothenburgSweden

flat metaoptics components are looking to replace classical optics elements and could lead to extremely compact biophotonics devices if integrated with on-chip light sources and ***,using metasurfaces to shape light into wide angular range wavefronts with high efficiency,as is typically required in high-contrast microscopy applications,remains a *** we demonstrate curved GaAs metagratings integrated on vertical-cavity surface-emitting lasers(VCSELs)that enable on-chip illumination in total internal reflection and dark field *** on an unconventional design that circumvents the aspect ratio dependent etching problems in monolithic integration,we demonstrate off-axis emission centred at 60°in air and 63°in glass with>90%and>70%relative deflection efficiency,*** resulting laser beam is collimated out-of-plane but maintains Gaussian divergence in-plane,resulting in a long and narrow illumination *** show that metagrating-integrated VCSELs of different kinds can be combined to enable rapid switching between dark-field and total internal reflection *** approach provides a versatile illumination solution for high-contrast imaging that is compatible with conventional microscopy setups and can be integrated with biophotonics devices,such as portable microscopy,NIR-II range bioimaging,and lab-on-a-chip devices.

关键词： illumination deflection optics

The Feasibility of flat, Portable and Wireless Device for Non-Invasive Peripheral Oxygenation Measurement over the Entire Body

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomedical Science and Engineering 2016年第3期9卷 147-159页

作者： Zehava Ovadia-Blechman Omri Gino Liron Dandeker Nadav Sheffer erik Baltaxe Vered Aharonson Medical Engineering Department Afeka Tel-Aviv Academic College of Engineering Tel Aviv Israel Electrical Engineering Department Afeka Tel-Aviv Academic College of Engineering Tel Aviv Israel Pulmonary Diseases and Internal Medicine Institute Sheba Medical Center Tel Hashomer Israel School of Electrical and Information Engineering University of the Witwatersrand Johannesburg South Africa

Peripheral oxygenation level (SpO2) can provide vital information on body functions. Continuous monitoring facilitates effective diagnosis and treatment and can even be lifesaving. Clinical device monitor SpO2 using a clip, and measure light transmission through the tissue. This method limits the body locations of the clip’s placement and is sensitive to body movement, which hampers continuous SpO2 monitoring during wakefulness or sleep, thus decreasing its usability in clinics and its accessibility in homecare usage. We developed a portable, wireless, flat and low cost prototype for continuous monitoring of SpO2 that overcomes those limitations. The prototype enables convenient measurement in larger variety of body locations by spectrophotometric measurements of changes in the optical reflectance unlike other device that measure absorption through the tissue. The original design and signal processing enable reliable signal acquisition, synchronization and control. An Android’s application was developed to provide a user friendly interface for results display on smartphones. The prototype’s measurements were compared to commercial device that simultaneously measured heart rate frequency, transcutaneous oxygen tension (tcPO2) and SpO2. The prototype’s measurements accurately reflected changes caused by blood pulses, were correlated to the heart rate, and were sensitive to changes in oxygen saturation. Excellent real time behavior and synchronization were demonstrated between the hardware and smartphone software. Our prototype thus enables convenient SpO2 measurement over the entire body, while maintaining accuracy comparable to commercial device. Its smartphone application enables accessible and understandable results display to patients, care-givers and healthcare professionals. The application’s display and alert calibration flexibility facilitates the prototype’s usage in changing medical

关键词： Peripheral Oxygen Saturation Noninvasive Monitoring Medical Application Pulse Oximetry

Longitudinally thickness-controlled nanofilms on exposed core fibres enabling spectrally flattened supercontinuum generation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Advanced Manufacturing) 2021年第3期2卷 76-87页

作者： Tilman A.KLühder Henrik Schneidewind erik P.Schartner Heike Ebendorff-Heidepriem Markus A.Schmidt Leibniz Institute of Photonic Technology Albert-Einstein-Str.907745 JenaGermany School of Physical Sciences and ARC Centre of Excellence for Nanoscale BioPhotonics(CNBP)and Institute for Photonics and Advanced Sensing(IPAS) The University of AdelaideAdelaide SA 5005Australia Otto Schott Institute of Material Research Fraunhoferstr.607743 JenaGermany Abbe School of Photonics and Physics Faculty Friedrich Schiller University07743 JenaGermany

Nonlinear frequency conversion is a pathway to unlock undiscovered physics and implement tailored light sources for spectroscopy or medicine.A key challenge is the establishment of spectrally flat outputs,which is particularly demanding in the context of soliton-based light conversion at low pump ***,we introduce the concept of controlling nonlinear frequency conversion by longitudinally varying resonances,allowing the shaping of soliton dynamics and achieving broadband spectra with substantial spectral *** varying resonances are realised by nanofilms with gradually changing thicknesses located on the core of an advanced microstructured *** with engineered thickness profiles are fabricated by tilted deposition,representing a waveguidecompatible approach to nano-fabrication,and inducing well-controlled resonances into the system,allowing unique dispersion control along the fibre *** features and dependencies are examined experimentally,showing improved bandwidth and spectral flatness via multiple dispersive wave generation and dispersionassisted soliton Raman shifts while maintaining excellent pulse-to-pulse stability and coherence in simulations,suggesting the relevance of our findings for basic science as well as tailored light sources.

关键词： waveguide pump soliton

热轧扁平材断面轮廓与平直度准稳态弹黏塑性离线模拟

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

世界钢铁 2012年第6期12卷 36-43页

作者： Alexander Kainz Markus Widder erik Parteder Gerald Hein Karl Schrkhuber Klaus Zeman 张国民约翰开普勒林茨大学西门子VAI冶金技术公司

为了预报宽板带在冷、热轧中的金属变形行为,需要借助精确的计算程序,并要考虑轧件变形和辊系变形间的耦合。对于又薄又宽的带材,即大宽厚比轧件,采用商用有限元软件模拟断面形状与平直度,需要耗费大量的计算时间[1,2]。开发了一个专业... 详细信息

为了预报宽板带在冷、热轧中的金属变形行为,需要借助精确的计算程序,并要考虑轧件变形和辊系变形间的耦合。对于又薄又宽的带材,即大宽厚比轧件,采用商用有限元软件模拟断面形状与平直度,需要耗费大量的计算时间[1,2]。开发了一个专业有限元程序[3-6],用于模拟轧制中轧件的弹黏塑性流动行为[7,8]。该方法基于准稳态理论和全隐式应力更新方法[9-12],考虑了轧件变形和辊系变形间的耦合[13],能够较准确得到轧件断面变化和内部残余应变、应力分布[14-16],据此可进行板带屈曲分析和平直度预报[17],以及轧机的断面形状与平直度调控能力评价[18,19]。所开发的模型基于鲁棒数值算法,计算结果与商用有限元软件模拟结果进行了对比验证,也将与热轧生产数据进行比较。该模型可用于系统深入地研究板形参数,开发冷、热轧带钢的平直度判据。值得一提的是,模型基于弹黏塑性本构关系,并考虑道次间的加工硬化与软化行为,得到了纵向应力、应变和轧制力横向分布。

关键词：热轧扁材断面轮廓与平直度断面轮廓变化辊系弹性弹黏塑性本构关系增量材料客观性定理残余应力应变