Coherers, a Review
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Nuclear Technology
Nuclear Technology Joseph A. Angelo, Jr. GREENWOOD PRESS NUCLEAR TECHNOLOGY Sourcebooks in Modern Technology Space Technology Joseph A. Angelo, Jr. Sourcebooks in Modern Technology Nuclear Technology Joseph A. Angelo, Jr. GREENWOOD PRESS Westport, Connecticut • London Library of Congress Cataloging-in-Publication Data Angelo, Joseph A. Nuclear technology / Joseph A. Angelo, Jr. p. cm.—(Sourcebooks in modern technology) Includes index. ISBN 1–57356–336–6 (alk. paper) 1. Nuclear engineering. I. Title. II. Series. TK9145.A55 2004 621.48—dc22 2004011238 British Library Cataloguing in Publication Data is available. Copyright © 2004 by Joseph A. Angelo, Jr. All rights reserved. No portion of this book may be reproduced, by any process or technique, without the express written consent of the publisher. Library of Congress Catalog Card Number: 2004011238 ISBN: 1–57356–336–6 First published in 2004 Greenwood Press, 88 Post Road West, Westport, CT 06881 An imprint of Greenwood Publishing Group, Inc. www.greenwood.com Printed in the United States of America The paper used in this book complies with the Permanent Paper Standard issued by the National Information Standards Organization (Z39.48–1984). 10987654321 To my wife, Joan—a wonderful companion and soul mate Contents Preface ix Chapter 1. History of Nuclear Technology and Science 1 Chapter 2. Chronology of Nuclear Technology 65 Chapter 3. Profiles of Nuclear Technology Pioneers, Visionaries, and Advocates 95 Chapter 4. How Nuclear Technology Works 155 Chapter 5. Impact 315 Chapter 6. Issues 375 Chapter 7. The Future of Nuclear Technology 443 Chapter 8. Glossary of Terms Used in Nuclear Technology 485 Chapter 9. Associations 539 Chapter 10. -
Wellesley News
COLLEGE TNEWS Vol. 3. No. 13. WELLESLEY, MASS., WEDNESDAY, JANUARY 13, 1904. Price, 5 Cents of forty-one dollars and seventy-three cents. Board, and the distinctively collegiate The International Institute League. This money was raised last spring. Noth- department, intended for advanced edu- With the first day of January, 1904, ing has as yet been done by the under- cation, especially in connection with the the International Institute League entered graduates during the current academic University of Madrid. This collegiate upon its first year of actual existence. It year. To this amount of forty-one dollars department will be undenominational, was born, in a sense, with a silver spoon and seventy-three cents members of the respecting the faith of Roman Catholic in its mouth, for it had paid all the bills faculty have added one hundred and students as of Protestants. It will be as incident to organization, amounting to thirty dollars, and alumna?, not of the international as it may, welcoming, in over three hundred dollars, and had five faculty, two hundred and fifty-six dollars addition-to its Spanish students, the daugh- hundred safe in its treasury and as much and thirty-six cents. So although the ters of the foreign legations in Madrid, and more definitely pledged. But this dower students have exceeded the twenty-five- American girls who may wish to avail did not drop swiftly and softly, as silver dollar limit, their contribution makes, after themselves of this new opportunity for spoons are fabled to do. from the tip of all, not a large proportion of the present studying the Spanish language, literature the rainbow. -
The Stage Is Set
The Stage Is Set: Developments before 1900 Leading to Practical Wireless Communication Darrel T. Emerson National Radio Astronomy Observatory1, 949 N. Cherry Avenue, Tucson, AZ 85721 In 1909, Guglielmo Marconi and Carl Ferdinand Braun were awarded the Nobel Prize in Physics "in recognition of their contributions to the development of wireless telegraphy." In the Nobel Prize Presentation Speech by the President of the Royal Swedish Academy of Sciences [1], tribute was first paid to the earlier theorists and experimentalists. “It was Faraday with his unique penetrating power of mind, who first suspected a close connection between the phenomena of light and electricity, and it was Maxwell who transformed his bold concepts and thoughts into mathematical language, and finally, it was Hertz who through his classical experiments showed that the new ideas as to the nature of electricity and light had a real basis in fact.” These and many other scientists set the stage for the rapid development of wireless communication starting in the last decade of the 19th century. I. INTRODUCTION A key factor in the development of wireless communication, as opposed to pure research into the science of electromagnetic waves and phenomena, was simply the motivation to make it work. More than anyone else, Marconi was to provide that. However, for the possibility of wireless communication to be treated as a serious possibility in the first place and for it to be able to develop, there had to be an adequate theoretical and technological background. Electromagnetic theory, itself based on earlier experiment and theory, had to be sufficiently developed that 1. -
Lecture 25 Demodulation and the Superheterodyne Receiver EE445-10
EE447 Lecture 6 Lecture 25 Demodulation and the Superheterodyne Receiver EE445-10 HW7;5-4,5-7,5-13a-d,5-23,5-31 Due next Monday, 29th 1 Figure 4–29 Superheterodyne receiver. m(t) 2 Couch, Digital and Analog Communication Systems, Seventh Edition ©2007 Pearson Education, Inc. All rights reserved. 0-13-142492-0 1 EE447 Lecture 6 Synchronous Demodulation s(t) LPF m(t) 2Cos(2πfct) •Only method for DSB-SC, USB-SC, LSB-SC •AM with carrier •Envelope Detection – Input SNR >~10 dB required •Synchronous Detection – (no threshold effect) •Note the 2 on the LO normalizes the output amplitude 3 Figure 4–24 PLL used for coherent detection of AM. 4 Couch, Digital and Analog Communication Systems, Seventh Edition ©2007 Pearson Education, Inc. All rights reserved. 0-13-142492-0 2 EE447 Lecture 6 Envelope Detector C • Ac • (1+ a • m(t)) Where C is a constant C • Ac • a • m(t)) 5 Envelope Detector Distortion Hi Frequency m(t) Slope overload IF Frequency Present in Output signal 6 3 EE447 Lecture 6 Superheterodyne Receiver EE445-09 7 8 4 EE447 Lecture 6 9 Super-Heterodyne AM Receiver 10 5 EE447 Lecture 6 Super-Heterodyne AM Receiver 11 RF Filter • Provides Image Rejection fimage=fLO+fif • Reduces amplitude of interfering signals far from the carrier frequency • Reduces the amount of LO signal that radiates from the Antenna stop 2/22 12 6 EE447 Lecture 6 Figure 4–30 Spectra of signals and transfer function of an RF amplifier in a superheterodyne receiver. 13 Couch, Digital and Analog Communication Systems, Seventh Edition ©2007 Pearson Education, Inc. -
High-Throughput Measurement of the Contact Resistance of Metal Electrode Materials and Uncertainty Estimation
electronics Article High-Throughput Measurement of the Contact Resistance of Metal Electrode mAterials and Uncertainty Estimation Chao Zhang and Wanbin Ren * School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin 150001, China; [email protected] * Correspondence: [email protected] Received: 30 October 2020; Accepted: 4 December 2020; Published: 6 December 2020 Abstract: Low and stable contact resistance of metal electrode mAterials is mAinly demanded for reliable and long lifetime electrical engineering. A novel test rig is developed in order to realize the high-throughput measurement of the contact resistance with the adjustable mechanical load force and load current. The contact potential drop is extracted accurately based on the proposed periodical current chopping (PCC) method in addition to the sliding window average filtering algorithm. The instrument is calibrated by standard resistors of 1 mW, 10 mW, and 100 mW with the accuracy of 0.01% and the associated measurement uncertainty is evaluated systematically. Furthermore, the contact resistance between standard indenter and rivet specimen is measured by the commercial DMM-based instruments and our designed test rig for comparison. The variations in relative expanded uncertainty of the measured contact resistance as a function of various mechanical load force and load current are presented. Keywords: electrode mAterial; high-throughput characterization; contact resistance; measurement; uncertainty estimation 1. Introduction Metal electrode mAterials are widely used in the electrical and electronic engineering for conducting and/or switching current, such as connectors [1], electromechanical devices [2], thin-film devices [3], microelectromechanical system [4], and switchgear [5], etc. The roughness of the mAterial surfaces causes only small peaks or asperities within the apparent surface to be in contact. -
Ballistic Transport and Tunneling in Small Systems Are Investigated Theoretically
BALLISTIC TRANSPORT AND TUNNELING IN SMALL SYSTEMS A- THESIS Submitted to the Deptirirxierii . vry ~*1 W-T» mr»· •1 ' » >·^ T”' · · o .A r ' ' ·' >. C, ' 4 r : ■* .r-» A "X ; rv * ■ f \ : J '■ ·' *1 P.--J i VI-J.W J W < ·'■■ * - w —W-« of Bilkent Unlveijicy iii ?-„rtia^. FulfilJraeni of the Req'iirer-enss for the Degree of Doctor of Pkilospixy A. ERICAN TLKMAN CBBR. 1990 BALLISTIC TRANSPORT AND TUNNELING IN SMALL SYSTEMS A THESIS SUBMITTED TO THE DEPARTMENT OF PHYSICS AND THE INSTITUTE OF ENGINEERING AND SCIENCE OF BILKENT UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSPHY By A. Erkan Tekman October 1990 'TS T 2 fe í> A' J К I certify that I have read this thesis and that in my opinion it is fully adequate, in scope and in quality, as a dissertation for the degree of Doctor of Philosophy. Prof. Salim Çıracı (Supervisor) I certify that I have read this thesis and that in my opinion it is fully adequate, in scope and in quality, as a dissertation for the degree of Doctor of Philosophy. Prof. M. Cerhal Yalabık I certify that I have read this thesis and that in my opinion it is fully adequate, in scope and in quality, as a dissertation for the degree of Doctor of Philosophy. Prof. Şinasi Ellialtioglu I certify that I have read this thesis and that in my opinion it is fully adequate, in scope and in quality, as a dissertation for the degree of Doctor of Philosophy. Assoc. Prof. Atilla Erçelebi I certify that I have read this thesis and that in my opinion it is fully adequate, in scope and in quality, as a dissertation for the degree of Doctor of Philosophy. -
Of Single Sideband Demodulation by Richard Lyons
Understanding the 'Phasing Method' of Single Sideband Demodulation by Richard Lyons There are four ways to demodulate a transmitted single sideband (SSB) signal. Those four methods are: • synchronous detection, • phasing method, • Weaver method, and • filtering method. Here we review synchronous detection in preparation for explaining, in detail, how the phasing method works. This blog contains lots of preliminary information, so if you're already familiar with SSB signals you might want to scroll down to the 'SSB DEMODULATION BY SYNCHRONOUS DETECTION' section. BACKGROUND I was recently involved in trying to understand the operation of a discrete SSB demodulation system that was being proposed to replace an older analog SSB demodulation system. Having never built an SSB system, I wanted to understand how the "phasing method" of SSB demodulation works. However, in searching the Internet for tutorial SSB demodulation information I was shocked at how little information was available. The web's wikipedia 'single-sideband modulation' gives the mathematical details of SSB generation [1]. But SSB demodulation information at that web site was terribly sparse. In my Internet searching, I found the SSB information available on the net to be either badly confusing in its notation or downright ambiguous. That web- based material showed SSB demodulation block diagrams, but they didn't show spectra at various stages in the diagrams to help me understand the details of the processing. A typical example of what was frustrating me about the web-based SSB information is given in the analog SSB generation network shown in Figure 1. x(t) cos(ωct) + 90o 90o y(t) – sin(ωct) Meant to Is this sin(ω t) represent the c Hilbert or –sin(ωct) Transformer. -
Electrical Engineering
SCIENCE MUSEUM SOUTH KENSINGTON HANDBOOK OF THE COLLECTIONS ILLUSTRATING ELECTRICAL ENGINEERING II. RADIO COMMUNICATION By W. T. O'DEA, B.Sc., A.M.I.E.E. Part I.-History and Development Crown Copyright Reseruea LONDON PUBLISHED BY HIS MAJESTY's STATIONERY OFFICI To be purchued directly from H.M. STATIONERY OFFICI at the following addre:11ea Adutral Houae, Kinpway, London, W.C.z; no, George Street, Edinburgh:& York Street, Manchester 1 ; 1, St, Andrew'• Cretccnr, Cudi.lf So, Chichester Street, Belfa1t or through any Booueller 1934 Price 2s. 6d. net CONTENTS PAGB PREFACE 5 ELECTROMAGNETI<: WAVF13 7 DETECTORS - I I EARLY WIRELESS TELEGRAPHY EXPERIMENTS 17 THE DEVELOPMENT OF WIRELESS TELEGRAPHY - 23 THE THERMIONIC vALVE 38 FuRTHER DEVELOPMENTS IN TRANSMISSION 5 I WIRELESS TELEPHONY REcEIVERS 66 TELEVISION (and Picture Telegraphy) 77 MISCELLANEOUS DEVELOPMENTS (Microphones, Loudspeakers, Measure- ment of Wavelength) 83 REFERENCES - 92 INDEX - 93 LIST OF ILLUSTRATIONS FACING PAGE Fig. I. Brookman's Park twin broadcast transmitters -Frontispiece Fig. 2. Hughes' clockwork transmitter and detector, 1878 8 Fig. 3· Original Hertz Apparatus - Fig. 4· Original Hertz Apparatus - Fig. S· Original Hertz Apparatus - 9 Fig. 6. Oscillators and resonators, 1894- 12 Fig. 7· Lodge coherers, 1889-94 - Fig. 8. Magnetic detectors, 1897, 1902 - Fig. 9· Pedersen tikker, 1901 I3 Fig. IO. Original Fleming diode valves, 1904 - Fig. II. Audion, Lieben-Reisz relay, Pliotron - Fig. IZ. Marconi transmitter and receiver, 1896 Fig. IJ. Lodge-Muirhead and Marconi receivers 17 Fig. 14. Marconi's first tuned transmitter, 1899 Fig. IS. 11 Tune A" coil set, 1900 - 20 Fig. 16. Marconi at Signal Hill, Newfoundland, 1901 Fig. -
The Development of the Coherer * and Some Theories of Coherer Action
268 SCIENTIFIC AMERICAN SUPPLEMENT No. 2 182 October 27, 1917 The Development of the Coherer * And Some Theories of Coherer Action By E. C. Green THE electric wave detecting device, first known as a Branly observed that the same effect occurred in the were exhibited. Lodge was the first to give the name Branly tube and later as a coherer, has been the subject case of two slightly oxidized steel or copper wires crossed Coherer to the Branly tube, a follows: "A coherer is of much research. Many experimentalists in past years in light contact, and further observed that this contact a device in which a loose or imperfect conducting contact noticed that a number of metals, when powdered, were resistance dropped from several thousand ohms to a few between pieces of metal is improved in conductivity by the practically non-conductors when a small electromotive ohms when an electric spark was produced many yards impact on it of electric radiation." Lodge's lecture force was impressed on the loosely compressed particles, away. caused widespread interest in Branly's discove"'ies and while they became good conductors when a high electro Branly's work did not secure the notice it deserved pointed out more forcibly that a new and highly sensitive motive force was applied. until 1892 when Dr. Dawson Turner described Branly's means of detecting electric radiation had been evolved. This knowledge can be traced as far back as 1835 to experiments and his own additions to them, at a meeting The coherer used by Lodg consisted of a glass tube Monk of Rosenschceld' who described the permanent of the British Association in Edinburgh." 1 cm. -
Making Radio Waves Telegraph
Making Radio Waves Telegraph Background Information What better way to demonstrate the detection of electromagnetic waves then to produce the electromagnetic waves (Radio waves) that are detected. Radio waves can be made by making a telegraph and a cohere detector can receive those radio waves. This early style telegraph generates a radio wave signal by producing a spark when the circuit is completed. Radio waves are produced by the spark. When there is a spark, electrons are transferred from one electrode to another as the electrons move, energy is transferred into heat, light, and a standing wave at the frequency of a radio wave. This allows the operator to generate radio waves by connecting and disconnecting the circuit respectively. In this design the switch is a piece of metal that is depressed to make contact, and released to open the circuit breaking the connection. (See photograph below) This circuit can be opened and closed easily in a pattern known as Morse code to send information wirelessly. A coherer detector is a historic radio wave detector made of common everyday materials. It consists of a tube containing some metal filings and two electrodes within millimeters of each other. Each electrode is connected to an observable resistor like a light bulb, speakers, or headphones. In the presence of a radio wave the metal filings form a bridge that completes a circuit. When the circuit is closed the radio wave becomes observable, success! The tube needs to be taped so that the metal filings will decoher and the detector is primed to detect another transmission. -
Cornell Gets a New Chair
PEOPLE APPOINTMENTS & AWARDS Cornell gets a new chair Two prominent accelerator physicists and Cornell alumni, Helen T Edwards and her husband, Donald A Edwards, have endowed a chair in accelerator physics at Cornell.The chair is named after Boyce D McDaniel, pro fessor emeritus at Cornell. The first holder of the new chair is David L Rubin, professor of physics and director of accelerator physics at Cornell.The donors David Rubin is the first incumbent of the new Boyce McDaniel Chair of Physics at Cornell, asked that the new professorship should be endowed by Helen and Donald Edwards. The chair is named after Boyce D McDaniel. Left awarded to a Cornell faculty member whose to right: Boyce McDaniel, Donald Edwards, David Rubin, Helen Edwards and Maury Tigner, discipline is particle-beam physics and who director of Cornell's Laboratory of Nuclear Studies. would teach both graduate and undergradu ate students in addition to doing research. McDaniel, a previous director of nuclear ingthe commissioning of the Main Ring at Helen Edwards is a 1957 graduate of science at Cornell, was Helen Edwards' thesis Fermilab and providing advice for numerous Cornell, where she also earned her PhD in adviser. Initially a graduate student at Cornell, accelerator projects throughout the US, in 1966. She works at Fermilab and at DESY in he left during the Second World War to join the addition to his notable contributions to the Germany. She played a prominent role in the Manhattan Project and returned to complete accelerator and elementary particle physics construction of Fermilab'sTevatron and has his PhD, joining the faculty in 1946. -
Arxiv:1211.4061V3 [Physics.Hist-Ph] 8 Feb 2013
From cosmic ray physics to cosmic ray astronomy: Bruno Rossi and the opening of new windows on the universe Luisa Bonolis Via Cavalese 13 – 00135 Rome, Italy [email protected] Abstract Bruno Rossi is considered one of the fathers of modern physics, being also a pioneer in virtually every aspect of what is today called high-energy astrophysics. At the beginning of 1930s he was the pioneer of cosmic ray research in Italy, and, as one of the leading actors in the study of the nature and behavior of the cosmic radiation, he witnessed the birth of particle physics and was one of the main investigators in this fields for many years. While cosmic ray physics moved more and more towards astrophysics, Rossi continued to be one of the inspirers of this line of research. When outer space became a reality, he did not hesitate to leap into this new scientific dimension. Rossi’s intuition on the importance of exploiting new technological windows to look at the universe with new eyes, is a fundamental key to understand the profound unity which guided his scientific research path up to its culminating moments at the beginning of 1960s, when his group at MIT performed the first in situ measurements of the density, speed and direction of the solar wind at the boundary of Earth’s magnetosphere, and when he promoted the search for extra-solar sources of X rays. A visionary idea which eventually led to the breakthrough experiment which discovered Scorpius X-1 in 1962, and inaugurated X-ray astronomy.