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南开大学学报（自然科学版） 2020年第1期53卷 55-60页

作者：赵启越张为刘艳艳天津大学微电子学院天津300072 南开大学电子信息与光学工程学院天津300071

提出了一种可用于0.1-1.2 GHz射频接收机前端的宽带巴伦低噪声放大器(Balun-LNA).采用噪声抵消技术,输入匹配网络的沟道热噪声和闪烁噪声在输出端被抵消,在宽带内可同时实现良好的输入匹配和低噪声性能.通过分别在输入匹配级内增加共源... 详细信息

提出了一种可用于0.1-1.2 GHz射频接收机前端的宽带巴伦低噪声放大器(Balun-LNA).采用噪声抵消技术,输入匹配网络的沟道热噪声和闪烁噪声在输出端被抵消,在宽带内可同时实现良好的输入匹配和低噪声性能.通过分别在输入匹配级内增加共源放大器,在噪声抵消级内增加共源共栅放大器实现单端转差分功能.电路采用电流复用技术降低系统功耗.设计基于TSMC 0.18μm CMOS工艺,LNA的最大增益达到13.5dB,噪声系数为3.2-4.1 d B,输入回波损耗低于-15 d B.在700 MHz处输入1 dB压缩点为-8 dBm,在1.8 v供电电压下电路的直流功耗为24 mW,芯片面积为0.062 5 mm^2.

关键词：宽带低噪声放大器噪声抵消电流复用单端转差分

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C-H Activation as a Shortcut to Conjugated Polymer Synthesis

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MACROMOLECULAR RAPID COMMUNICATIONS 2019年第1期40卷 e1800512页

作者： Blaskovits, J. Terence Leclerc, Mario Univ Laval Dept Chem Quebec City PQ G1V 0A6 Canada

Direct (hetero)arylation polymerization exploits the palladium-catalyzed activation of aromatic C-H bonds for the atom-economical synthesis of conjugated polymers for a wide range of applications. This account outlines how direct arylation methodologies overcome many of the limitations of contemporary polymerization techniques at both the research and production scale, and explains how monomer design and reaction conditions must be tailored to ensure high polymer molecular weight, yield, and structural integrity. current research aims to improve further this reaction's profile as a sustainable methodology while at the same time making it competitive with the Migita-Stille and Miyaura-Suzuki polymerizations both in scope of accessible structures and synthetic efficiency. This feature article charts the recent developments and future directions of C-H activation research as it moves toward becoming at once an industrially feasible, environmentally friendly, and synthetically powerful polymerization technique.

关键词： C-H activation conjugated polymer synthesis direct (hetero)arylation polymerization green chemistry palladium catalysis

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Frequency-Dependent Squeezed vacuum Source for the Advanced virgo Gravitational-Wave Detector

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Physical Review Letters 2023年第4期131卷 041403-041403页

作者： F. Acernese M. Agathos A. Ain S. Albanesi C. Alléné A. Allocca A. Amato C. Amra M. Andia T. Andrade N. Andres M. Andrés-Carcasona T. Andrić S. Ansoldi S. Antier T. Apostolatos E. Z. Appavuravther M. Arène N. Arnaud M. Assiduo S. Assis de Souza Melo P. Astone F. Aubin S. Babak F. Badaracco S. Bagnasco J. Baird T. Baka G. Ballardin G. Baltus B. Banerjee P. Barneo F. Barone M. Barsuglia D. Barta A. Basti M. Bawaj M. Bazzan F. Beirnaert M. Bejger v. Benedetto M. Berbel S. Bernuzzi D. Bersanetti A. Bertolini U. Bhardwaj A. Bianchi M. Bilicki S. Bini M. Bischi M. Bitossi M.-A. Bizouard F. Bobba M. Boër G. Bogaert G. Boileau M. Boldrini L. D. Bonavena R. Bondarescu F. Bondu R. Bonnand v. Boschi v. Boudart Y. Bouffanais A. Bozzi C. Bradaschia M. Braglia M. Branchesi M. Breschi T. Briant A. Brillet J. Brooks G. Bruno F. Bucci O. Bulashenko T. Bulik H. J. Bulten R. Buscicchio D. Buskulic C. Buy G. Cabras R. Cabrita G. Cagnoli E. Calloni M. Canepa G. Caneva Santoro M. Cannavacciuolo E. Capocasa G. Carapella F. Carbognani M. Carpinelli G. Carullo J. Casanueva Diaz C. Casentini S. Caudill R. Cavalieri G. Cella P. Cerdá-Durán E. Cesarini W. Chaibi P. Chanial E. Chassande-Mottin S. Chaty P. Chessa F. Chiadini G. Chiarini R. Chierici A. Chincarini M. L. Chiofalo A. Chiummo N. Christensen S. Chua G. Ciani P. Ciecielag M. Cieślar M. Cifaldi R. Ciolfi S. Clesse F. Cleva E. Coccia E. Codazzo P.-F. Cohadon A. Colombo M. Colpi L. Conti I. Cordero-Carrión S. Corezzi S. Cortese J.-P. Coulon J.-F. Coupechoux M. Croquette J. R. Cudell E. Cuoco M. Curyło P. Dabadie T. Dal Canton S. Dall’Osso G. Dálya B. D’Angelo G. Dangoisse S. Danilishin S. D’Antonio v. Dattilo M. Davier J. Degallaix M. De Laurentis S. Deléglise F. De Lillo D. Dell’Aquila W. Del Pozzo F. De Matteis A. Depasse R. De Pietri R. De Rosa C. De Rossi R. De Simone L. Di Fiore C. Di Giorgio F. Di Giovanni M. Di Giovanni T. Di Girolamo D. Diksha A. Di Lieto A. Di Michele J. Ding S. Di Pace I. Di Palma F. Di Renzo L. D’Onofrio T. Dooney O. Dorosh M. Drago J.-G. Ducoin U. Dupletsa O Dipartimento di Farmacia Università di Salerno I-84084 Fisciano Salerno Italy INFN Sezione di Napoli I-80126 Napoli Italy Theoretisch-Physikalisches Institut Friedrich-Schiller-Universität Jena D-07743 Jena Germany INFN Sezione di Pisa I-56127 Pisa Italy Dipartimento di Fisica Università degli Studi di Torino I-10125 Torino Italy INFN Sezione di Torino I-10125 Torino Italy Université Savoie Mont Blanc CNRS Laboratoire d’Annecy de Physique des Particules - IN2P3 F-74000 Annecy France Università di Napoli “Federico II” I-80126 Napoli Italy Maastricht University 6200 MD Maastricht Netherlands Nikhef 1098 XG Amsterdam Netherlands Institut Fresnel Faculté des Sciences St Jérôme Avenue Escadrille Normandie-Niemen F-13013 Marseille France Université Paris-Saclay CNRS/IN2P3 IJCLab 91405 Orsay France Institut de Ciències del Cosmos (ICCUB) Universitat de Barcelona (UB) carrer Martí i Franquès 1 08028 Barcelona Spain Institut de Física d’Altes Energies (IFAE) Barcelona Institute of Science and Technology and ICREA E-08193 Barcelona Spain Gran Sasso Science Institute (GSSI) I-67100 L’Aquila Italy Dipartimento di Scienze Matematiche Informatiche e Fisiche Università di Udine I-33100 Udine Italy INFN Sezione di Trieste I-34127 Trieste Italy Université Côte d’Azur Observatoire Côte d’Azur CNRS Artemis F-06304 Nice France Department of Physics National and Kapodistrian University of Athens 15771 Ilissia Greece INFN Sezione di Perugia I-06123 Perugia Italy Università di Camerino I-62032 Camerino Italy Université Paris Cité CNRS Astroparticule et Cosmologie F-75013 Paris France European Gravitational Observatory (EGO) I-56021 Cascina Pisa Italy Università degli Studi di Urbino “Carlo Bo” I-61029 Urbino Italy INFN Sezione di Firenze I-50019 Sesto Fiorentino Firenze Italy INFN Sezione di Roma I-00185 Roma Italy Université catholique de Louvain B-1348 Louvain-la-Neuve Belgium Institute for Gravitational and Subatomic Physics (GRASP) Utrecht Universi

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

关键词： Gravitation Gravitational waves Gravitational wave detectors

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design and implementation of A power conversion system on A bicycle with utilisation by sensors 2

Design and implementation of A power conversion system on A ...

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2nd International Conference on I-SMAC (IoT in Social, Mobile, Analytics and Cloud), I-SMAC 2018

作者： Prabhu, Rohith S. vasudev, Neeraj Nandu, v. Lokesh, K.J. Anudev, J. Department of Electrical and Electronics Engineering Amrita School of Engineering Amrita Vishwa Vidyapeetham Amritapuri India

ISBN: (纸本)9781538614426

It is evident that the rate of cycling nowadays has reduced even though the benefits are lump sum. Being physically active has posed to be a challenge in the current generation. Power that is developed from human beings can be manipulated for major developments in any country. Heart related diseases, obesity, sugar levels and many major illnesses can be taken under control by regular physical activity. This paper focuses on design and implementation of a cycle that can be used as a routine basis where the user is able to generate power by cycling. Such a design that is ergonomic, efficient and safe for use in normal livelihood. Physical activity monitoring systems, energy consumed, conversion systems are designed and implemented here. © 2018 IEEE.

关键词： Accelerometers

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v-shaped Nano-Antennas on Titanium Dioxide as a Tunable Plasmonic Lens 26

V-shaped Nano-Antennas on Titanium Dioxide as a Tunable Plas...

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26th Iranian Conference on Electrical engineering (ICEE)

作者： Rafaei-Booket, Mahmood Bozorgi, Mahdieh Univ Zanjan Fac Elect & Comp Engn Zanjan Iran

ISBN: (纸本)9781538649169

A tunable planar lens metasurface composed of a gold array on a Titanium dioxide slab is presented. Each cell of such a structure comprised of a v-shaped gold nano-antenna on a uniaxial anisotropic substrate. In the design of such a planar lens, the phase diagram of the cross-polarized scattered field is obtained using a spectral domain calculation based on dyadic Green's function. This function, which is obtained by employing the transmission line (TL) model, appears in an integral equation. By solving the integral equation using Galerkin's Method of Moments (MoM) with the appropriate entire domain functions, the effective surface current densities on the gold array is determined. A series of v-shaped elements with the different dimensions are selected, based on the equal optical length principle, to satisfy the phase discontinuities of each cell. Finally, the lens metasurface illuminated by the plane wave is analyzed by using an electromagnetic simulator. The obtained results indicate the optic axis rotation of the anisotropic substrate leads to controlling the intensity of the lens focuses.

关键词： anisotropic substrate dyadic Green's function metasurface Method of Moments tunable plasmonic lens

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A phoswich detector design for improved spatial sampling in PET

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2018年 882卷 124-128页

作者： Thiessen, Jonathan D. Koschan, Merry A. Melcher, Charles L. Meng, Fang Schellenberg, Graham Goertzen, Andrew L. Lawson Hlth Res Inst Imaging Program London ON Canada Univ Western Ontario Dept Med Biophys London ON Canada Univ Manitoba Dept Radiol 702 John Buhler Res Ctr715 McDermot Ave Winnipeg MB R3E 3P4 Canada Univ Tennessee Scintillat Mat Res Ctr Knoxville TN USA Univ Manitoba Dept Phys & Astron Winnipeg MB Canada

Block detector designs, utilizing a pixelated scintillator array coupled to a photosensor array in a light-sharing design, are commonly used for positron emission tomography (PET) imaging applications. In practice, the spatial sampling of these designs is limited by the crystal pitch, which must be large enough for individual crystals to be resolved in the detector flood image. Replacing the conventional 2D scintillator array with an array of phoswich elements, each consisting of an optically coupled side-by-side scintillator pair, may improve spatial sampling in one direction of the array without requiring resolving smaller crystal elements. To test the feasibility of this design, a 4 x 4 phoswich array was constructed, with each phoswich element consisting of two optically coupled, 3.17 x 1.58 x 10 mm(3) LSO crystals co-doped with cerium and calcium. The amount of calcium doping was varied to create a 'fast' LSO crystal with decay time of 32.9 ns and a 'slow' LSO crystal with decay time of 41.2 ns. Using a Hamamatsu R8900U-00-C12 position-sensitive photomultiplier tube (PS-PMT) and a CAEN v1720 250 MS/s waveform digitizer, we were able to show effective discrimination of the fast and slow LSO crystals in the phoswich array. Although a side-by-side phoswich array is feasible, reflections at the crystal boundary due to a mismatch between the refractive index of the optical adhesive (n = 1.5) and LSO ( n = 1.82) caused it to behave optically as an 8 x 4 array rather than a 4 x 4 array. Direct coupling of each phoswich element to individual photodetector elements may be necessary with the current phoswich array design. Alternatively, in order to implement this phoswich design with a conventional light sharing PET block detector, a high refractive index optical adhesive is necessary to closely match the refractive index of LSO. (C) 2017 Elsevier B.v. All rights reserved.

关键词： Positron emission tomography Phoswich detector LSO

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The electron accelerators for the AWAKE experiment at CERN-Baseline and Future developments

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2018年 909卷 102-106页

作者： Pepitone, K. Doebert, S. Apsimon, R. Bauche, J. Bernardini, M. Bracco, C. Burt, G. Chauchet, A. Chevallay, E. Chritin, N. Curt, S. Damerau, H. Kelisani, M. Dayyani Delory, C. Fedosseev, v. Friebel, F. Galleazzi, F. Gorgisyan, I. Gschwendtner, E. Hansen, J. Jensen, L. Keeble, F. Maricalva, L. Mazzoni, S. McMonagle, G. Mete, O. Pardons, A. Pasquino, C. verzilov, v. Schmidt, J. S. Soby, L. Williamson, B. Yamakawa, E. Pitman, S. Mitchell, J. CERN Geneva Switzerland Univ Lancaster Lancaster England Univ Manchester Manchester Lancs England Triumf Vancouver BC Canada UCL London England

The AWAKE collaboration prepares a proton driven plasma wakefield acceleration experiment using the SPS beam at CERN. A long proton bunch extracted from the SPS interacts with a high power laser and a 10 m long rubidium vapor plasma cell to create strong wakefields allowing sustained electron acceleration. The electron beam to probe these wakefields is created by an electron accelerator consisting of an rf-gun and a booster structure. This electron source should provide beams with intensities between 0.1 and 1 nC, bunch lengths between 0.3 and 3 ps and an emittance of the order of 2 mm mrad. The booster structure should accelerate the electrons to 16 Mev. The electron line includes a series of diagnostics (pepper-pot, BPMs, spectrometer, Faraday cup and screens) and an optical transfer line merges the electron beam with the proton beam on the same axis. The installation of the electron line started in early 2017 and the commissioning will take place at the end of 2017. The first phase of operation is called RUN1. After the long shutdown of LHC a second phase for AWAKE is planned starting 2021 called RUN2. In this phase the aim is to demonstrate the acceleration of high quality electron beams therefore a bunch length of the order of 100 fs rms is required corresponding to a fraction of the plasma wavelength. The AWAKE collaboration is studying the design of such an injector either based on classical rf-gun injectors or on laser wake-field acceleration. The focus for the RF accelerator is on a hybrid design using an S-band rf-gun and x-band bunching and acceleration cavities. The layout of the current and the future electron accelerator and transfer line, including the diagnostics will be presented.

关键词： Electron gun Accelerators Charged particle beams in accelerators Diagnostics

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Probabilistic methods for systems engineering with application to nanosatellite laser communications

Probabilistic methods for systems engineering with applicati...

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作者： Clements, Emily Baker Massachusetts Institute of Technology

学位级别：博士

Risk-tolerant platforms such as nanosatellites may be able to accept moderate performance uncertainty if it enables the reduction of cost or improves manufacturability, in contrast to large-budget space missions. New uncertainty-based systems engineering approaches such as uncertainty-based multidisciplinary optimization require the use of integrated performance models with input distributions, which do not yet exist for complex systems, e.g. laser communications (lasercom) payloads. In this thesis, we present our development of a statistical, risk-tolerant systems engineering approach and apply it to nanosatellite-based design and architecture problems to investigate whether adding a statistical element to systems engineering enables improvements in performance, manufacturability, and cost. The scope of this work is restricted to a subset of nanosatellite-based lasercom systems, which are particularly useful given current momentum to field Earth observing nanosatellite constellations and challenges for data retrieval. We build uncertainty-based lasercom performance models for a low Earth orbiting (LEO) system being developed at MIT called the Nanosatellite optical Downlink Experiment (NODE) as a reference architecture. Compared with a more traditional, deterministic systems engineering approach, we find our probabilistic approach leads to a lasercom downlink design with a 59% reduction in ground station diameter and a 46% reduction in space terminal power for equivalent probabilities of a LEO-ground system delivering 500 Gb/day. We compare the data volume and latency performance of five communication architectures for nanosatellite constellations with and without lasercom crosslinks: two ground stations vs. nine ground stations with (i and ii) lasercom and (iii and iv) X-band, and (v) UHF with one ground station. For example, we find that a 30-satellite Walker delta constellation of 6U satellites with an optical downlink to nine ground stations and optical crosslin

关键词： Aeronautics and Astronautics

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Microbial fuel cells: recent developments in design and materials

Microbial fuel cells: recent developments in design and mate...

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International Conference on Recent Advances in Materials, Mechanical and Civil engineering (ICRAMMCE)

作者： Bhargavi, G. venu, v. Renganathan, S. Anna Univ Dept Biotechnol Madras Tamil Nadu India Marri Laxman Reddy Inst Technol & Management Dept Mech Engn Hyderabad 500043 Telangana India

Microbial Fuel Cells (MFCs) are the promising devices which can produce electricity by anaerobic fermentation of organic/inorganic matter from easily metabolized biomass to complex wastewater using microbes as biocatalysts. MFC technology has been found as a potential technology for electricity generation and concomitant wastewater treatment. However, the high cost of the components and low efficiency are barricading the commercialization of MFC when compared with other energy generating systems. The performance of an MFC is largely relying on the reactor design and electrode materials. On the way to improve the efficiency of an MFC, tremendous exercises have been carried out to explore new electrode materials and reactor designs in recent decades. The current review is excogitated to amass the progress in design and electrode materials, which could bolster further investigations on MFCs to improve their performance, mitigate the cost and successful implementation of technology in field applications as well.

关键词： Microbial fuel cells

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Three Sigma and Multilevel Active Contour Approach to Detect Optic Disc and Optic Cup

Three Sigma and Multilevel Active Contour Approach to Detect...

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Advanced Technologies in Intelligent Control, Environment, Computing & Communication engineering (ICATIECE), International Conference on

作者： N C Patil P v Rao Department of ECE T John Institute of Technology Bangalore Department of ECE VBIT Hyderabad

ISBN: (数字)9781728104188

ISBN: (纸本)9781728112664

One of the key factors to be looked at during design of an automated eye screening system is to find the optic disc and optic cup. Objective: In eye screening of diabetic patients, the feature such as hard exudates and cotton wool spots can be noticed which share similar properties with optic disc In certain diseases like glaucoma ophthalmologist look at the ratio of optic cup with optic disc to detect the presence or absence of glaucoma currently, the process is manual performed by ophthalmologist, which a time consuming and tedious job. This fact motivated to design a fully automated procedure to detect optic cup and optic disc. Method: In the current paper a multilevel active contour technique is used that generates the snake to detect boundaries of optic cup and optic disc using intensity of the border pixels which are tested using 3σ control limits. The algorithm works in two parts. In part-1, optic disc boundary is detected and in part-2, the optic cup is marked by concentrating inside the area marked as optic disc in part-1. Findings: This approach reduces processing area and hence improves computational time A local database to carry out this work was created by collecting images from Karnataka Institute of Diabetology, Bangalore The results obtained by the proposed procedure are encouraging and have yielded 100% results with the fundus images containing full optic disc Improvement: The method is fully automatic and no user intervention is required.

关键词： optical imaging optical filters Biomedical optical imaging optical distortion Blood vessels Retina

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