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Conference on Optics for EUv, X-Ray, and Gamma-Ray Astronomy IX as part of the SPIE Optics + Photonics International Symposium on optical engineering + Applications

作者： Salmaso, B. Basso, S. Giro, E. Spiga, D. Sironi, G. vecchi, G. Ghigo, M. Pareschi, G. Tagliaferri, G. Uslenghi, M. Fiorini, M. Paoletti, L. Ferrari, C. Beretta, S. Zappettini, A. del Rio, M. Sanchez Pelliciari, C. Burwitz, v. Ferreira, I. Bavdaz, M. INAF Astron Observ Brera Via E Bianchi 46 I-23807 Merate Lecco Italy INAF IASF Milano Via A Corti 12 I-40133 Milan Italy INAF Astron Observ Padova Vicolo Osservatorio 5 I-35122 Padua Italy CNR IMEM Parco Area Sci 37-A I-43124 Parma Italy European Synchrotron Radiat Facil BP 220 F-38043 Grenoble France Max Planck Inst Extraterr Phys Garching Germany European Space Agcy Estec Keplerlaan 1 NL-2201 AZ Noordwijk Netherlands

ISBN: (数字)9781510629325

ISBN: (纸本)9781510629325

The ATHENA X-ray telescope comprises an optical system with several hundreds of Silicon Pore Optics (SPO) Mirror Modules (MM) to be assembled. All the MMs have to be tested for acceptance before integration. INAF-Osservatorio Astronomico Brera is building in its premises of Merate (Italy) a unique pathfinder facility, BEaTriX, which is characterized by a broad (170 x 60 mm(2)), uniform and parallel X-ray beam (divergence <= 1.5 arcsec HEW) at the energies of 1.49 and 4.51 kev. BEaTriX prime goal is to prove that it is possible to perform the acceptance tests (PSF and Aeff) of the ATHENA SPO MM's at the production rate of 3 MM/day. The system is very compact (9 x 18 m(2)) and it is designed with modular compartments where the vacuum can be broken independently to replace the optics under test. It works at a vacuum level of 10(-3) mbar, easily evacuated in a short time. The expanded and parallel beam is obtained with an X-ray microfocus source placed in the focus of a paraboloidal mirror, a monochromation stage with 4 symmetrically cut crystals, and an expansion stage where the beam is diffracted and expanded by an asymmetrically-cut crystal. The key axes of all the optical components are motorized in vacuum for a proper beam alignment. The expanded beam fully illuminates the aperture of the MMs, imaging the focused beam at 12 m distance on a CCD camera, with the sensor in vacuum and motorized in air for XYZ movements. A thermal box is also present to radiatively heat the MM and check its optical performances under different temperatures. The design of the facility started in 2012 and has been finalised under an ESA contract. After completing the design, the facility is now in the realization phase. This paper provides an overview of the current status of the facility realization.

关键词： ATHENA BEaTriX X-ray testing X-ray microfocus source beam expander asymmetric diffraction

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Further developments of Fusion-Enabling System in Russia: Suggestions on Superconductors and current Leads for DEMO-FNS Reactor

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IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIvITY 2018年第3期28卷 1-5页

作者： Lelekhov, S. A. Krasil'nikov, A. v. Kuteev, B. v. Kovalev, I. A. Ivanov, D. P. Ryazanov, A. I. Surin, M. I. Shavkin, S. v. vysotsky, v. S. Potanina, L. v. Svalov, G. G. Abdyukhanov, I. M. Alekseev, M. v. Tsapleva, A. S. Pantsyrny, v. I. Zapretilina, E. R. Rodin, I. Y. voronova, A. A. Project Ctr ITER DA RF Moscow 123182 Russia Natl Res Ctr Kurchatov Inst Moscow 123182 Russia Joint Stock Co VNIIKP Moscow 111024 Russia Natl Res Nucl Univ MEPhI Moscow Engn Phys Inst Moscow 115409 Russia Bochvar Inst Moscow 123098 Russia Efremov Inst St Petersburg 196641 Russia

New fusion devices are being discussed in Russia. One item is a superconducting magnet development for the demonstration hybrid facility-fusion neutron source based on a tokamak concept with the conventional aspect ratio similar to 3. The magnetic parameters of this device are planned to be: 5 T on the plasma axis and about 12 T on the high field side of the toroidal field coils. Because of a high neutron flow and a thick shielding, the space remained for the inner legs of the toroidal field coil is very tight. Therefore, a very high current density is needed for the windings. Several magnet designs have been addressed up to now with required engineering critical current density sim 1000 A/mm(2) at least. In this review, we present conceptual design of the magnet system, necessary strand parameters, and their irradiation properties. Few possible designs of the toroidal field, conductors are discussed. The R&D of efficient HTS current leads to be used for fusion machines are discussed as well.

关键词： Fusion neutron source internal Tin Nb3Sn strand cable-in-conduit conductor HTS current leads irradiation

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Projectile impact on fabric-metal assemblies - Influence of fabric-metal sequence

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INTERNATIONAL JOURNAL OF IMPACT engineering 2019年 127卷 1-16页

作者： Guo, Y. B. Chiang, H. J. Deng, J. J. Shim, v. P. W. Natl Univ Singapore Dept Mech Engn Impact Mech Lab 9 Engn Dr 1 Singapore 117575 Singapore Nanjing Univ Sci & Technol Sch Mech Engn Nanjing Jiangsu Peoples R China

Fabrics woven from high-strength fibres are increasingly employed for protection against projectile impact, because of superior mechanical properties. In some applications, high-strength fabrics are combined with metallic components to provide sufficient structural rigidity and strength - e.g. for vehicle bodies, turbine engine fragment barriers, building doors, etc. An understanding of how the fabric-metal layer sequence affects the resulting ballistic resistance, is essential for effective design of such fabric-metal assemblies. This motivates the current study, whereby multiple plies (1, 2 or 4) of Twaron (T) aramid fabric were combined with an aluminium alloy (A) thin plate to form a lightweight protective panel. The projectile impact penetration resistance of three types of fabric-metal arrangements were examined - i) the aluminium alloy plate as the impact face;ii) the Twaron fabric as the impacted layer;iii) the aluminium alloy plate sandwiched between fabric layers. For assemblies with a smaller number of fabric plies (i.e. 1 or 2), siting the aluminium alloy plate as the rearmost layer results in a significantly higher impact energy absorption capacity, compared to having the aluminium alloy plate as the impact face - e.g. for (A +1T) assemblies, i.e. A1 plate + 1 ply of Twaron, IT/A (impact face layer appears first in this nomenclature) performs much better than A/1T. For (A + 2T) assemblies, 2T/A provides the highest impact resistance, A/2T is the weakest, and 1T/A/IT lies in between. However, when the number of fabric plies is increased to 4, a variety of responses was observed. An A/4T configuration absorbs significantly higher energy than a 4T/A arrangement, while a symmetrical 2T/A/2T sequence absorbs less energy than either an A/4T or 4T/A configuration. High-speed optical photography images and post-test specimens were analysed, to examine the deformation and failure modes of the fabric plies and A1 plate in the fabric-metal targets, and how they ar

关键词： Fabric-metal assemblies Arrangement sequence Projectile impact Ballistic limit Impact energy absorption capacity

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Effect of aluminide coatings on penetration and microstructure of TIG welded 9Cr-1Mo steel for fusion blanket applications

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FUSION engineering AND design 2019年第0期144卷 172-179页

作者： Zala, A. B. Jamnapara, N., I Badheka, v. J. Sam, S. Ranjan, M. Inst Plasma Res Near Indira Bridge Bhat 382428 Gujarat India Homi Bhabha Natl Inst 2nd FloorBARC Training Sch Complex Mumbai 400094 Maharashtra India Pandit Deendayal Petr Univ Raisan Sch Techol Dept Mechancial Engn Gandhinagar 382421 Gujarat India

Aluminide coatings with a top alumina layer on 9Cr steels are considered candidates for fusion blanket applications. One of the critical issues associated with such coating is the fabrication sequence. It is therefore important to investigate the effect of aluminide coating on weld properties of 9Cr steels. This work is a preliminary investigation of the weldability of aluminide coated 9Cr-1Mo steels using bead-on-plate welding experiments. Alumina coated GRADE 91 steel samples by hot dip aluminizing followed by normalizing and plasma tempering were generated. Bead-on-plate welding studies were conducted at different heat inputs by varying the weld speed (100,125,150 mm/min) and using a constant current of 200A by autogenous tungsten inert gas (TIG) welding process. The effect of coating on the weld microstructure was investigated using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive x-rays (SEM-EDX) and microhardness tests. It was observed that the presence of alumina (Al2O3) on the top of coated samples resulted in improved depth of penetration (DOP) due to arc constriction. The presence of Al rich inclusions (AlN) in the weld bead were also observed. The marginal increase in Al concentration of the weld bead appears to reduce the grain size of weld metal for coated sample and microhardness was enhanced compared to the uncoated 9Cr-1Mo steels.

关键词： Aluminized 9Cr-1Mo steels TIG welding Depth of penetration (DOP) Microstructure

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Artificial Neural Network based controller design for SMPS

Artificial Neural Network based controller design for SMPS

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International Conference on Recent developments in Control, Automation and Power engineering (RDCAPE)

作者： Mohammad Ali Khan Prashant Anand G. Bhuvaneswari Indian Institute of Technology Delhi Delhi India Faculty of Electrical Engineering IIT Delhi

This paper presents a novel approach to design a controller for a half-bridge converter based Switched Mode Power Supply of 150W rating. A half-bridge converter is designed for obtaining a stiffly regulated DC output voltage of 5v irrespective of load and supply voltage variations, with an artificial neural network (ANN) based controller. The duty ratio of the controller is determined by this ANN depending on the input voltage and the output load conditions. Data collection for training the ANN was done using a PID controller-based approach in which the transfer function for the SMPS was derived by performing the large signal and small signal analyses and appropriate parameter values for the PID controller were calculated. For different load and input supply voltage conditions, the output voltage was regulated by making use of the PID controller and appropriate duty ratios were arrived at. These 150 data points were used for the training the proposed ANN with four hidden layers. The trained neural network was further utilized in arriving at the duty ratio value directly by sensing the input voltage and load current and it is found to yield stiffly regulated voltage irrespective of supply voltage and load variations where the error is within 8 %.

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Development and manufacturing of SPO X-ray mirrors 9

Development and manufacturing of SPO X-ray mirrors

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Optics for EUv, X-Ray, and Gamma-Ray Astronomy IX 2019

作者： Landgraf, Boris Collon, Maximilien J. vacanti, Giuseppe Barrière, Nicolas M. Günther, Ramses vervest, Mark voruz, Luc verhoeckx, Sjoerd Babić, Ljubiša Keek, Laurens Girou, David Okma, Ben Beijersbergen, Marco W. Bavdaz, Marcos Wille, Eric Fransen, Sebastiaan Shortt, Brian Ferreira, Ivo Haneveld, Jeroen Koelewijn, Arenda Start, Ronald Wijnperlé, Maurice Lankwarden, Jan-Joost van Baren, Coen Hieltjes, Paul Den Herder, Jan Willem Burwitz, vadim Pareschi, Giovanni Massahi, Sonny Della Monica Ferreira, Desirée Christensen, Finn E. valsecchi, Giuseppe Oliver, Paul Chequer, Ian Ball, Kevin Cosine Oosteinde 36 HE Warmond2361 Netherlands European Space Agency ESTEC Keplerlaan 1 PO Box 299 AG Noordwijk2200 Netherlands Micronit Microfluidics B.V. Colosseum 15 PV Enschede7521 Netherlands SRON Sorbonnelaan 2 CA Utrecht3584 Netherlands MPI F. Extraterrestrische Physik Giessenbachstrasse 1 Garching85748 Germany I-23807 Italy DTU Space Technical University of Denmark Building 327 Kgs. LyngbyDK - 2800 Denmark 23842 Italy Ltd. 106 Waterhouse Lane Chelmsford EssexCM1 2QU United Kingdom

ISBN: (数字)9781510629325

ISBN: (纸本)9781510629318

The Silicon Pore Optics (SPO) technology has been established as a new type of X-ray optics enabling future X-ray observatories such as ATHENA. SPO is being developed at cosine together with the European Space Agency (ESA) and academic as well as industrial partners. The SPO modules are lightweight, yet stiff, high-resolution X-ray optics, allowing missions to reach a large effective area of several square meters. These properties of the optics are mainly linked to the mirror plates consisting of mono-crystalline silicon. Silicon is rigid, has a relatively low density, a very good thermal conductivity and excellent surface finish, both in terms of figure and surface roughness. For Athena, a large number of mirror plates is required, around 100,000 for the nominal configuration. With the technology spin-in from the semiconductor industry, mass production processes can be employed to manufacture rectangular shapes SPO mirror plates in high quality, large quantity and at low cost. Within the last years, several aspects of the SPO mirror plate have been reviewed and undergone further developments in terms of effective area, intrinsic behavior of the mirror plates and mass production capability. In view of flight model production, a second source of mirror plates has been added in addition to the first plate supplier. The paper will provide an overview of most recent plate design, metrology and production developments. © 2019 SPIE.

关键词： Mirrors

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Introduction to a topical issue 'nonlinear energy transfer in dynamical and acoustical Systems'

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PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND engineering SCIENCES 2018年第2127期376卷 1-6页

作者： Gendelman, O. v. vakakis, A. F. Technion Israel Inst Technol Fac Mech Engn IL-3200003 Haifa Israel Univ Illinois Dept Mech Sci & Engn Urbana IL 61801 USA

This topical issue is devoted to recent developments in the broader field of energy transfer across scales in nonlinear dynamical and acoustical systems. Nonlinear energy transfers are common in Nature, with perhaps the most famous example being energy cascading from large to small length scales in turbulent flows. Yet nonlinearity has been traditionally perceived either as an unavoidable nuisance or as an unwelcome design restriction in engineering systems. Nowadays, however, this trend is reversing, with nonlinear phenomena being intensely studied in diverse disciplines. Furthermore, strong nonlinearity is now intentionally used and explored in a variety of mechanical and physical settings, such as granular media, acoustic metamaterials, nonlinear energy sinks, essentially nonlinear and nonlocal lattices, vibro-impact oscillators, vibration and shock isolation systems, nanotechnology, biomimetic systems, microelectronics, energy harvesters and in other applications. This topical issue is an attempt to document in a single volume some of these recent research developments, in order to establish a common basis and provide motivation and incentive for further development. The aim is to discuss and compare theoretical and experimental approaches pursued by research groups in different areas, and describe the state of the art of nonlinear energy transfer phenomena in an as broad as possible range of applications of current interest. This article is part of the theme issue 'Nonlinear energy transfer in dynamical and acoustical systems'.

关键词： nonlinear dynamics wave propagation targeted energy transfer solitary waves breathers nanostructures

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Comparison between the Arclight Ophthalmoscope and a Standard handheld Direct Ophthalmoscope: a Clinical study 19

Comparison between the Arclight Ophthalmoscope and a Standar...

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19th Conference on current developments in Lens design and optical engineering

作者： Parthasarathy, Mohana Kuppuswamy Faruq, Ibrahim Arthurs, Eugene Lakshminarayanan, vasudevan Univ Waterloo Sch Optometry & Vis Sci Waterloo ON Canada Costco Opt Waterloo ON Canada SPIE Bellingham WA USA Univ Waterloo Dept Phys Waterloo ON Canada Univ Waterloo Dept ECE Waterloo ON Canada Univ Waterloo Dept Syst Design Engn Waterloo ON Canada

ISBN: (数字)9781510620629

ISBN: (纸本)9781510620629

The direct ophthalmoscope, a handheld device gives a highly magnified image of the retina. However, the sustainability of power source and cost are a limitation considering the usage demand. We compared a low-cost solar-powered Arclight ophthalmoscope with a standard ophthalmoscope Heine K180 in terms of ease of examination, usage, field of view, color rendition and patient comfort. Two clinically trained optometrists examined 28 patients and graded the ease of retinal examination, ease of use and assessed cup-disc ratio, which is an important diagnostic parameter for glaucoma, patient comfort and length of examination (scale 1-4). The examiners had good agreement for all assessments. Of a total of 78 examinations, only 8(10.3%) did not result in cup-disc ratio measurement in the undilated pupil condition using both devices. Ease of use was scored higher for Arclight than Heine but this was not statistically significant. In conditions like large discs, the Arclight resulted in easier examinations due to its larger field of view. Color rendition was better with the Heine device. In undilated pupils, the patients often reported that there was significant glare with Heine, however, post-dilation, they reported more glare with Arclight compared to Heine (73% versus 55%). The performance of Arclight was comparable to that of Heine and can be considered a low-cost alternative to the standard direct ophthalmoscope especially in large-scale patient examinations in developing countries where cost might be a factor.

关键词： Direct Ophthalmoscope Retina ophthalmology cup to disc ratio Arclight ophthalmoscope Heine ophthalmoscope solar powered ophthalmoscope

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Naturally-derived biopolymer nanocomposites: Interfacial design, properties and emerging applications

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MATERIALS SCIENCE & engineering R-REPORTS 2018年 125卷 1-41页

作者： Xiong, Rui Grant, Anise M. Ma, Ruilong Zhang, Shuaidi Tsukruk, vladimir v. Georgia Inst Technol Sch Mat Sci & Engn Atlanta GA 30332 USA

Naturally derived materials with hierarchical organization are attractive candidates for high-performance and functional bionanocomposites because of their renewability, biocompatibility, biodegradability, flexibility, and the availability of multiple reactive sites for introducing novel functionalities. Complementary to these inherent properties, the synergistic combination of biological and synthetic components facilitated by strong interfacial interactions, can substantially enhance the structural performance and facilitate added functionalities of these bio-enabled nanocomposites. In this review, we discuss the current progress of naturally-derived bionanocomposites that has advanced our understanding of the biological/synthetic interfaces. In these bionanocomposites, various novel synthetic nanomaterials (e.g., graphene, carbon nanotube, mineral nanoparticles and metallic nanoparticles) are efficiently integrated with biological components to achieve novel properties such as superior electrical and thermal conductivity, controlled gas barrier properties, complex actuation, and unique optical properties. Two popular biocomponents, nanocellulose and silk, are mainly discussed in this review as representatives of classes of polysaccharides and polypeptides with some other biopolymers briefly discussed as well. The structures and morphologies, processing strategies, tailored functionalities and emerging applications of these bionanocomposites are analyzed and summarized. Finally, we present an outlook on the current trends in providing structural and interfacial enhancement as well as emerging applications which will employ new optical, sensing, structural, and actuating functionalities and properties. (C) 2018 Elsevier B.v. All rights reserved.

关键词： Bionanocomposites Natural polymers Nanocellulose Silk fibroin Mechanical performance Functional properties

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Recent developments in Next-Generation Microchannel Plates for Particle Identification Applications 21

Recent Developments in Next-Generation Microchannel Plates f...

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Conference on Uv, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXI held at SPIE optical engineering + Applications Conference

作者： Cremer, Till Adams, Bernhard W. Aviles, Melvin Ertley, Camden D. Foley, Michael R. Lyashenko, Alexey Minot, Michael J. Popecki, Mark A. Rivera, Travis Stochaj, Michael E. Elam, Jeffrey W. Mane, Anil U. Gebhard, Maximilian Siegmund, Oswald H. Incom Inc 294 Southbridge Rd Charlton MA 01507 USA Argonne Natl Lab 9700 South Cass Ave Lemont IL 60439 USA Univ Calif Berkeley Space Sci Lab 7 Gauss Way Berkeley CA 94720 USA

ISBN: (数字)9781510629301

ISBN: (纸本)9781510629295;9781510629301

Incom Inc. is developing and commercializing a novel type of microchannel plate (MCP) electron multipliers. These new devices are called "ALD-GCA-MCPs" and are made from glass capillary arrays (GCA), glass plates with a regular array of hollow glass capillaries that are functionalized using atomic layer deposition (ALD) thin film coating technology. ALD-GCA-MCPs are a technology advancement that affords MCPs with significantly improved performance, as compared to conventional MCPs. Notable benefits over conventional lead-oxide based MCPs are larger size, high and stable gain, low dark counts and gamma-ray sensitivity, improved mechanical stability, and the unique ability to tune the MCP resistance and electron amplification characteristics over a much wider range and independent from the glass substrate. Incom now routinely produces ALD-GCA-MCPs with 10 and 20 mu m pore size at MCP dimensions up to 20 cm x 20 cm. The MCPs show a number of favorable characteristics, such as 3x lower gamma-ray sensitivity compared to conventional MPCs, low background (< 0.05 cts/s/cm(2)), and stable, high gains (>1x10(4) for single MCP and >1x10(7) for a chevron pair configuration, at 1000v/MCP). ALD-GCA-MCPs find use in a variety of photon counting applications and are particularly suited for charged particle detection that requires high timing and spatial resolution, such as Ion time-of-flight (TOF), electron spectroscopies, analytical and space instruments, and MCP-based photomultipliers such as the Large-Area Picosecond Photodetector (LAPPDTM), which is also being developed by Incom Inc. In this paper, we provide a brief technology overview highlighting the current state of the art of Incom's ALD-GCA-MCP technology, as well as current and future development efforts that address the GCA glass substrate as well as the resistive and electron emissive ALD coatings.

关键词： Atomic Layer Deposition Micro Channel Plate Photodetector Glass Capillary Array Tunable Resistance Materials Secondary Electron Emission

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