scholarly journals Generation of the current normal to the surface of antenna by electromagnetic waves and its application in the high responsive receiver

2021 ◽  
Vol 24 (1) ◽  
pp. 76-82
Author(s):  
V.N. Dobrovolsky ◽  

Generation of the initial current normal to the surface of antenna by electromagnetic waves has been considered. It has been shown that the angle of grazing (or sliding) for the wave with the electric vector in the plane normal to the surface varies the radiation resistance over a wide range. This property allows matching the radiation impedances and loads. Here, it has been proposed to use this property to create a highly- sensitive radiation detector. In relation with this task, a model of the radiation detection of the input radiation signal by a direct quadratic detector in the stationary mode with the diode included as the load has been considered. The obtained results prove that a diode with the high differential resistance can effectively operate with the antenna. The rise of the resistance increases the detector response voltage, its responsivity, and decreases the receiver noise equivalent power. Improvement of these characteristics by orders of magnitude is possible. The considered mechanism allows detectors to operate in the infrared spectral range, and the increase in the wavelength, in principle, does not limit its functioning.

Author(s):  
Anthony S-Y Leong ◽  
David W Gove

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.


1984 ◽  
Vol 30 (5) ◽  
pp. 784-787 ◽  
Author(s):  
R A Gibson ◽  
L Lattanzio ◽  
H McGee

Abstract Metronidazole and its known metabolites in plasma can be rapidly separated by a "high-pressure" liquid-chromatographic method that can also be adapted for rapid determination of tinidazole. Samples deproteinized with trichloroacetic acid (50 g/L final concentration) undergo isocratic separation on a reversed-phase C18 column eluted with an 8/92 (by vol) mixture of acetonitrile/KH2PO4 (5 mmol/L, pH 3.0). The method is sensitive, reliably detecting as little as 25 micrograms of metronidazole and (or) its metabolites per milliliter of plasma. The detector response varied linearly with concentration for all compounds tested over a wide range (25-500 micrograms/L). Within-day and between-day variation was generally less than 2.5% for all concentrations of all compounds tested. Various other antibiotics tested did not interfere.


2021 ◽  
Vol 251 ◽  
pp. 03055
Author(s):  
John Blue ◽  
Braden Kronheim ◽  
Michelle Kuchera ◽  
Raghuram Ramanujan

Detector simulation in high energy physics experiments is a key yet computationally expensive step in the event simulation process. There has been much recent interest in using deep generative models as a faster alternative to the full Monte Carlo simulation process in situations in which the utmost accuracy is not necessary. In this work we investigate the use of conditional Wasserstein Generative Adversarial Networks to simulate both hadronization and the detector response to jets. Our model takes the 4-momenta of jets formed from partons post-showering and pre-hadronization as inputs and predicts the 4-momenta of the corresponding reconstructed jet. Our model is trained on fully simulated tt events using the publicly available GEANT-based simulation of the CMS Collaboration. We demonstrate that the model produces accurate conditional reconstructed jet transverse momentum (pT) distributions over a wide range of pT for the input parton jet. Our model takes only a fraction of the time necessary for conventional detector simulation methods, running on a CPU in less than a millisecond per event.


Nukleonika ◽  
2015 ◽  
Vol 60 (3) ◽  
pp. 591-596 ◽  
Author(s):  
Aneta Malinowska ◽  
Marian Jaskóła ◽  
Andrzej Korman ◽  
Adam Szydłowski ◽  
Karol Malinowski ◽  
...  

Abstract To use effectively any radiation detector in high-temperature plasma experiments, it must have a lot of benefits and fulfill a number of requirements. The most important are: a high energy resolution, linearity over a wide range of recorded particle energy, high detection efficiency for these particles, a long lifetime and resistance to harsh conditions existing in plasma experiments and so on. Solid-state nuclear track detectors have been used in our laboratory in plasma experiments for many years, but recently we have made an attempt to use these detectors in spectroscopic measurements performed on some plasma facilities. This paper presents a method that we used to elaborate etched track diameters to evaluate the incident projectile energy magnitude. The method is based on the data obtained from a semiautomatic track scanning system that selects tracks according to two parameters, track diameter and its mean gray level.


2010 ◽  
Vol 18 (3) ◽  
Author(s):  
A.V. Voitsekhovskii ◽  
S.N. Nesmelov ◽  
S.M. Dzyadukh ◽  
V.S. Varavin ◽  
S.A. Dvoretskii ◽  
...  

AbstractThe paper examines influence of near-surface graded-gap layers on electrical characteristics of MIS-structures fabricated on heteroepitaxial Hg1−xCdxTe films grown by molecular beam epitaxy (MBE). Two types of insulators, i.e., two-layer SiO2/Si3N4 and anodic oxide films were used. As it is seen from the depth and width of the valley on the C-V characteristics, the capacitance is found to vary in a wide range, in contrast to the structures without graded-gap layers. It is shown that the graded-gap layer under MIS-structures with x = 0.22 effectively reduces the tunnelling generation via deep levels and increases a lifetime of minority carriers in the space charge region and its differential resistance. The properties of the HgCdTe-insulator interfaces are studied.


2018 ◽  
Vol 64 ◽  
pp. 131-148
Author(s):  
J. Brian Davies

Alex Cullen combined the sharpest of scientific minds with a gentle personality and a great sense of humour. He was Professor and Head of the Department of Electrical Engineering at Sheffield from 1955 to 1967, and then Head of the Department of Electrical Engineering at University College London (UCL) until 1980. He continued his research there as a Science and Engineering Research Council Senior Fellow until 1985, and for some years as Research Fellow of UCL. His research concerned electromagnetic waves over a wide range of microwave devices and measurement techniques, the latter at a fundamental level. These contributions were of a highly innovative and ‘ground-breaking’ nature. He was appointed OBE in 1960, and elected Fellow of the Royal Society in 1977. He was an accomplished jazz musician, playing drums and clarinet. He was a signatory of a letter to The Times in January 1986, calling on Prime Minister Margaret Thatcher to ‘Save British Science’. This led to the foundation of the Save British Science pressure group, now the Campaign for Science and Engineering (CaSE), which has built up an enviable reputation with politicians and the media in representing the concerns of scientists and engineers. When (now Sir) Eric Ash left UCL in 1985 to become Rector of Imperial College, he remarked that Alex was ‘the last gentleman in the business’.


2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Aozhen Xie ◽  
Chathuranga Hettiarachchi ◽  
Francesco Maddalena ◽  
Marcin E. Witkowski ◽  
Michał Makowski ◽  
...  

Author(s):  
R. Leicht ◽  
G. G. Simon

Basic tasks in all monitoring projects involving gamma spectroscopy are design optimization and calibration of the Ge gamma spectrometer system which in general consists of one or more Ge detectors, the corresponding collimators, and the object with radioactive material (container, drum, wall, material on a conveyor etc.). A simplified approach to these problems has been developed by RWE NUKEM GmbH, leading to the software tool “ISO-Mod” which provides a straightforward comprehensive approach for the assessment and analysis of the most common cases without any need for other resources. The detector response is measured with calibration sources as a function of gamma energy, distance and polar angle. The effect of collimators is evaluated for rotational symmetry and for rectangular design based on polygon cross sections, with the possibility to have one or more layers of specific materials. The object model allows considering cubic (e. g. box, material on conveyor) or cylindrical (e. g. drum) absorption matrix and activity distributions with additional optional absorption layers. For considering the absorption in the object matrix and in the collimator material, mass attenuation coefficients are available for a wide range of energy. A number of selected gamma energies and matrix densities can be evaluated in a single evaluation run using Point Kernel and Monte Carlo simulation methods. For selected energies and densities, ISO-Mod provides the probability distribution of the calibration data. This allows investigating the sensitivity to potentially non-homogeneous activity distributions, e. g. to assess the improvement achieved when using more than one detector since up to 4 detectors can be considered simultaneously. All design data and results are — hierarchically structured — stored in a particular database. ISO-Mod is currently being used in different monitoring projects involving conveyor belts, containers and drums with radioactive material. Good agreement was found between the calculations and the results of measurements using calibrated point and homogeneous extended volume sources. Particular procedures are applied for locating hot spots in waste packages with multi-detector systems.


Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1756
Author(s):  
Shinpei Ogawa ◽  
Masafumi Kimata

Plasmonics and metamaterials are growing fields that consistently produce new technologies for controlling electromagnetic waves. Many important advances in both fundamental knowledge and practical applications have been achieved in conjunction with a wide range of materials, structures and wavelengths, from the ultraviolet to the microwave regions of the spectrum. In addition to this remarkable progress across many different fields, much of this research shares many of the same underlying principles, and so significant synergy is expected. This Special Issue introduces the recent advances in plasmonics and metamaterials and discusses various applications, while addressing a wide range of topics in order to explore the new horizons emerging for such research.


2012 ◽  
Vol 13 (1) ◽  
pp. 47 ◽  
Author(s):  
Benny D. Bruton ◽  
Wayne W. Fish

In 2010, a foliar and stem-lesion disease was observed for the first time in Oklahoma causing moderate to severe defoliation. Using microscopic examination, the physical features of the fungus were consistent with Myrothecium roridum. There was a wide range of susceptibility among watermelon cultivars in the field indicating a moderately high level of resistance to Myrothecium leaf spot in some cultivars. In greenhouse inoculation experiments, cantaloupe, honeydew, cucumber, squash, and watermelon were all susceptible to the fungus with cantaloupe and honeydew being the most susceptible and watermelon the most resistant. Furthermore, greenhouse inoculations supported the field observations as differential resistance was exhibited among the watermelon cultivars as well as the cucurbit types. Although cantaloupe was most susceptible to the foliar phase of this disease, watermelon was most susceptible to the fruit-rot phase. Natural infection of watermelon fruit has never been reported. Accepted for publication 15 December 2011. Published 30 January 2012.


Sign in / Sign up

Export Citation Format

Share Document