480 results on '"Pulsed mode"'
Search Results
102. Bubble-type Motion Detector Using a Pulsed-mode Oscillator and Delay Line
- Author
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Dong-Wook Kim and Ik-Hwan Lee
- Subjects
Physics ,Motion detector ,Vackář oscillator ,Optics ,business.industry ,Bubble ,Electronic engineering ,Delay line oscillator ,Pulsed mode ,Type (model theory) ,business ,Line (electrical engineering) - Published
- 2015
103. A Magnetic Resonance Probehead for Evaluating the Level of Ionizing Radiation Absorbed in Human Teeth
- Author
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Aharon Blank, Benjamin B. Williams, Rizwan Ahmad, Ygal Twig, and Helen Woflson
- Subjects
Materials science ,Epidemiology ,Health, Toxicology and Mutagenesis ,Signal-To-Noise Ratio ,Signal ,Ionizing radiation ,Optics ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Irradiation ,Dental Enamel ,Radiometry ,Mechanical Phenomena ,Microwave resonators ,medicine.diagnostic_test ,business.industry ,Electron Spin Resonance Spectroscopy ,Absorption, Radiation ,Tooth Injuries ,Magnetic resonance imaging ,Equipment Design ,Magnetostatics ,Calibration ,Pulsed mode ,Nuclear medicine ,business ,Sensitivity (electronics) - Abstract
A miniature electron spin resonance (ESR) probehead that includes a static field source and a microwave resonator for in vivo measurement of paramagnetic defects in tooth enamel was developed. These defects are known to be a good marker for quantifying the ionizing radiation dose absorbed in teeth. The probehead has a typical length of just 30 mm and total weight of 220 g. The patient "bites" into the probehead while the measurement procedure is being carried out. The probehead operates in pulsed mode at a frequency of ∼ 11.2 GHz and supplies a static magnetic field of ∼ 400 mT. A detailed design of the probehead is provided together with its specifications in terms of measurement volume and signal-to-noise ratio for a typical sample. A specially developed simulation program was used to predict the spatial distribution of the acquired signal under conditions of grossly inhomogeneous static and RF fields. Experimental results with irradiated incisor teeth validated the probehead's sensitivity, being able to detect signals in tooth irradiated by only 2 Gy. Subject to additional improvements and tests, this type of probehead can potentially have significant clinical applications ranging from mass triage following major nuclear events to routine occupational evaluation of ionizing radiation absorbed over long periods of time.
- Published
- 2015
104. Análise da ação do gel da Bryophyllum calycinum Salisb (folha santa) associado ao ultrassom na cicatrização de feridas cutâneas
- Author
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Valdiléia Teixeira Uchôa, Nelson Jorge Carvalho Batista, Pablo Diêgo Leal Costa, João Lenon de Sousa, Antônio Luiz Martins Maia Filho, and Wellington dos Santos Alves
- Subjects
Type III collagen ,lcsh:Diseases of the musculoskeletal system ,Traditional medicine ,biology ,Chemistry ,business.industry ,Ultrasound ,Pulsed Ultrasound ,General Medicine ,biology.organism_classification ,Bryophyllum ,Pulsed mode ,Medicinal herbs ,lcsh:RC925-935 ,lcsh:Sports medicine ,business ,Wound healing ,lcsh:RC1200-1245 - Abstract
Introdução: A cicatrização é uma cascata de eventos celulares que interagem para que ocorra a reconstituição do tecido. Objetivo: Analisar a ação do gel da Bryophyllum calycinum Salisb, associado ao ultrassom pulsado, na cicatrização de feridas. Métodos: Vinte ratos foram feridos, divididos em quatro grupos, tratados e observados diariamente. O Grupo1 não recebeu nenhum tratamento; o 2 foi tratado com ultrassom (modo pulsado 10%, frequência de 1 MHz, intensidade de 0,5 W/cm2, método de acoplamento direto com movimentos oscilatórios numa ERA de 1 cm2, durante dois minutos) + gel da B. calycinum Salisb a 2%; o 3, com gel da B. calycinum Salisb a 2%; o 4, com ultrassom. Resultados: O Grupo 2 teve maior redução das áreas feridas, diminuição do colágeno tipo III e aumento do tipo I, quando comparado ao controle. Conclusões: O gel da folha santa associado ao ultrassom é capaz de acelerar o processo de cicatrização tecidual.
- Published
- 2015
105. Ring laser having an output at a single frequency
- Author
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Hackell, Lloyd [Livermore, CA]
- Published
- 1991
106. High brilliance negative ion and neutral beam source
- Author
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Compton, Robert [Oak Ridge, TN]
- Published
- 1991
107. Apparatus for coating a surface with a metal utilizing a plasma source
- Author
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Galvin, James [Emeryville, CA]
- Published
- 1991
108. Fast pulsed excitation wiggler or undulator
- Author
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van Steenbergen, Arie [Shoreham, NY]
- Published
- 1990
109. High‐performance operation of distributed feedback terahertz quantum cascade lasers
- Author
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Zhanguo Wang, Fengqi Liu, Junqi Liu, Jinchuan Zhang, and Yuanyuan Li
- Subjects
Materials science ,business.industry ,Terahertz radiation ,020208 electrical & electronic engineering ,02 engineering and technology ,Grating ,Laser ,01 natural sciences ,law.invention ,Power (physics) ,010309 optics ,Optics ,law ,Cascade ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Optoelectronics ,Pulsed mode ,Electrical and Electronic Engineering ,business ,Quantum ,Diffraction grating - Abstract
Carefully designed distributed feedback terahertz quantum cascade lasers based on surface metallic-stripe grating structure are presented. Stable single-mode emission with a side-mode suppression ratio of >20 dB is obtained under all injection currents and operating temperatures. Maximum edge-emitting power of 58 mW is realised in continuous-wave mode. In pulsed mode, record output powers of 286 mW at 10 K and 82 mW at 77 K are achieved at 97.1 μm with a well-shaped beam pattern.
- Published
- 2016
110. [ERCP procedures as a source of radiation risk to a single gastroenterologist]
- Author
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Krzysztof Kujawski, Renata Kopeć, Maria A. Staniszewska, and Krzysztof Sasak
- Subjects
Male ,medicine.medical_specialty ,Radiology, Interventional ,Radiation Dosage ,01 natural sciences ,Effective dose (radiation) ,Gastroenterology ,03 medical and health sciences ,ERCP ,0302 clinical medicine ,Radiation Protection ,Radiation Monitoring ,Internal medicine ,Occupational Exposure ,0103 physical sciences ,X-rays ,Medical Staff, Hospital ,Medicine ,Fluoroscopy ,Humans ,Cholangiopancreatography, Endoscopic Retrograde ,Endoscopic retrograde cholangiopancreatography ,medicine.diagnostic_test ,Radiology Department, Hospital ,010308 nuclear & particles physics ,business.industry ,Equivalent dose ,lcsh:Public aspects of medicine ,Gastroenterologists ,Public Health, Environmental and Occupational Health ,Interventional radiology ,lcsh:RA1-1270 ,General Medicine ,Reference Standards ,doses ,fluoroscopy ,Radiation risk ,Radiological weapon ,Pulsed mode ,030211 gastroenterology & hepatology ,Female ,gastroenterologist ,Poland ,business ,Nuclear medicine - Abstract
One of the numerous sub-areas of interventional radiology is the use of X-rays in gastroenterology. X-ray fluoroscopy is applied in therapeutic procedures, including endoscopic retrograde cholangiopancreatography (ERCP) that is frequently performed. The ERCP procedure is aimed at imaging the pancreatic duct and biliary tracts.In this paper radiation risk to the gastrenterologist performing ERCP procedures was investigated. The procedures were performed by a single gastroenterologist in the ERCP Laboratory, University Clinical Hospital Military Memorial Medical Academy - Central Veterans' Hospital in Łódź, Poland. The study comprised 2 series of measurements, one taken during the procedures with continuous fluoroscopy mode, the other during procedures with fluoroscopy in pulsed mode at a frequency of 3 pulses/s. Exposure parameters, anatomical data of patient and dose equivalents for the eyes, skin of the hand and the effective dose for whole body of the gastroenterologist were recorded during each procedure.The collected data cover 70 ERCP procedures - 40 procedures were controlled by continuous fluoroscopy and 30 by pulsed fluoroscopy. The results reveal that pulsed fluoroscopy makes it possible to reduce doses received by the gastroeneterologist from 45% to 60% compared to continuous fluoroscopy.Endoscopic retrograde cholangiopancreatography procedures can cause radiation risk to the gastroenterologist performing them. The use of continuous fluoroscopy can result in achieving an equivalent dose to eye lens nearly 20 mSv per year, i.e., the decreased annual limit recommended by the International Commission on Radiological Protection (ICRP). Med Pr 2017;68(6):735-741.Wykorzystanie promieniowania rentgenowskiego (rtg.) w gastroenterologii stanowi jeden z licznych podobszarów radiologii interwencyjnej. W gastroenterologii fluoroskopia rtg. jest używana w procedurach terapeutycznych, z których częsta jest endoskopowa cholangiopankreatografia wsteczna (ECPW). Procedura ECPW pokazuje radiologiczny obraz dróg żółciowych i przewodu trzustkowego.W ramach niniejszej pracy przeprowadzono ocenę narażenia na promieniowanie rtg. gastroenterologa wykonującego zabiegi ECPW pod kontrolą fluoroskopii. Badania przeprowadzono w Pracowni ECPW Uniwersyteckiego Szpitala Klinicznego im. Wojskowej Akademii Medycznej – Centralnego Szpitala Weteranów w Łodzi, gdzie gastroenterolog wykonuje je samodzielnie. Realizując cel pracy, wykonano 2 serie pomiarów – pierwsza składała się z zabiegów wykonanych w trybie fluoroskopii ciągłej, druga – z zabiegów, które wykonano w trybie fluoroskopii impulsowej (o częstotliwości 3 pulsy/s). Podczas każdej procedury rejestrowano parametry ekspozycji, dane anatomiczne pacjenta, a także otrzymywane przez gastroenterologa równoważniki dawek dla soczewek oczu i skóry dłoni oraz dawkę efektywną dla całego ciała.Zebrano dane dotyczące ogółem 70 zabiegów ECPW, w tym 40 zabiegów wykonanych w trybie fluoroskopii ciągłej i 30 – w trybie fluoroskopii impulsowej. Na podstawie uzyskanych wyników stwierdzono, że gastroenterolog wykonujący procedury ECPW w trybie fluoroskopii impulsowej otrzymuje dawki promieniowania niższe o 45–60% niż podczas pracy w trybie fluoroskopii ciągłej.Procedury ECPW mogą być źródłem narażenia na promieniowanie rtg. dla wykonującego je gastroenterologa. Używanie trybu fluoroskopii ciągłej może pozwolić na osiągnięcie obniżonej wartości rocznego limitu dawki równoważnej dla soczewek oczu (tj. 20 mSv), rekomendowanej przez Międzynarodową Komisję Ochrony Radiologicznej (International Commission on Radiological Protection – ICRP). Med. Pr. 2017;68(6):735–741.
- Published
- 2017
111. Activation calculations for the target of a spallation ultra-cold neutron source at PSI
- Author
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Michael Wohlmuther and Jan Züllig
- Subjects
Monte Carlo method ,Cyclotron ,Radiation Dosage ,law.invention ,Nuclear physics ,Radiation Protection ,law ,Shielded cable ,Radiology, Nuclear Medicine and imaging ,Neutron ,Spallation ,Computer Simulation ,Linear Energy Transfer ,Nuclide ,Radiometry ,Physics ,Neutrons ,Radiation ,Radiological and Ultrasound Technology ,Public Health, Environmental and Occupational Health ,General Medicine ,Equipment Design ,Cyclotrons ,Models, Theoretical ,Equipment Failure Analysis ,Pulsed mode ,Neutron source ,Algorithms ,Switzerland - Abstract
A spallation ultra-cold neutron source--UCN source--is scheduled to start operation at PSI in 2006 using up to 2 mA 590 MeV protons from the ring cyclotron. It will be operated in a pulsed mode with an average current of 20 microA. For safe maintenance, during operation as well as handling, transport and storage of the UCN target assembly after its lifespan, detailed knowledge about the activation induced by the impinging protons and secondary radiation fields is required. The Monte Carlo transport code MCNPX was coupled with the European Activation System--EASY--to calculate the residual nuclide production in the UCN target assembly. The nuclide inventory is finally used to design the shielded exchange flask that is needed to safely remove and transport the UCN target assembly after its lifespan to a hotcell for dismantling.
- Published
- 2017
112. Pulsed black-body emitter based on current-driven carbon nanotube fibers
- Author
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Junichiro Kono, Ahmed Zubair, Matteo Pasquali, Jean Leotin, O. Drachenko, Dmitri E. Tsentalovich, and Xuan Wang
- Subjects
Materials science ,business.industry ,Terahertz radiation ,Physics::Optics ,02 engineering and technology ,Carbon nanotube ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Temperature measurement ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Thermal ,Physics::Accelerator Physics ,Optoelectronics ,Pulsed mode ,Current (fluid) ,0210 nano-technology ,business ,Indium gallium arsenide ,Common emitter - Abstract
We have developed an ultrabroadband thermal light emitter based on carbon nanotube fibers driven either by continuous or pulsed current. Particularly, in pulsed mode, this emitter provides shorter and more intense pulses of terahertz radiation than conventional thermal emitters.
- Published
- 2017
113. Evaluation of the low-level laser therapy application parameters for skin burn treatment in experimental model: a systematic review
- Author
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Patricia Brassolatti, Paulo Sérgio Bossini, Albaiza Nicoletti Otterço, Ana Laura Martins de Andrade, and Nivaldo Antonio Parizotto
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Dermatology ,Cochrane Library ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Laser therapy ,medicine ,Animals ,Humans ,Medical physics ,Total energy ,Low-Level Light Therapy ,Low level laser therapy ,Skin ,Protocol (science) ,Wound Healing ,Experimental model ,business.industry ,Burn treatment ,030206 dentistry ,Evaluation Studies as Topic ,Pulsed mode ,Surgery ,business ,Burns - Abstract
Burn is defined as a traumatic injury of thermal origin, which affects the organic tissue. Low-level laser therapy (LLLT) has gained great prominence as a treatment in this type of injury; however, the application parameters are still controversial in the literature. The aims of this study were to review the literature studies that use LLLT as a treatment in burns conducted in an experimental model, discuss the main parameters used, and highlight the benefits found in order to choose an appropriate therapeutic window to be applied in this type of injury. The selection of the studies related to the theme was carried out in the main databases (PubMed, Cochrane Library, LILACS, Web of Science, and Scopus in the period from 2001 to 2017). Subsequently, the articles were then chosen that fell within the inclusion criteria previously established. In the end, 22 were evaluated, and the main parameters were presented. The analyzed studies presented both LLLT use in continuous and pulsed mode. Differences between the parameters used (power, fluence, and total energy) were observed. In addition, the protocols are distinct as to the type of injury and the number of treatment sessions. Among the results obtained by the authors are the improvements in the local microcirculation and cellular proliferation; however, a study reported no effects with LLLT as a treatment. LLLT is effective in accelerating the healing process. However, there is immense difficulty in establishing the most adequate protocol, due to the great discrepancy found in the applied dosimetry values.
- Published
- 2017
114. Experimental study of quantum random number generator based on two independent lasers
- Author
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Shi-Hai Sun and Feihu Xu
- Subjects
Physics ,Quantum Physics ,business.industry ,Probabilistic logic ,FOS: Physical sciences ,Laser ,01 natural sciences ,law.invention ,010309 optics ,Generator (circuit theory) ,law ,0103 physical sciences ,Phase noise ,Optoelectronics ,Pulsed mode ,Hardware random number generator ,010306 general physics ,business ,Quantum Physics (quant-ph) ,Quantum ,Randomness - Abstract
Quantum random number generator (QRNG) can produce true randomness by utilizing the inherent probabilistic nature of quantum mechanics. Recently, the spontaneous-emission quantum phase noise of the laser has been widely deployed for QRNG, due to its high rate, low cost and the feasibility of chip-scale integration. Here, we perform a comprehensive experimental study of phase-noise based QRNG with two independent lasers, each of which operates in either continuous-wave (CW) or pulsed mode. We implement QRNGs by operating the two lasers in three configurations, namely CW+CW, CW+pulsed and pulsed+pulsed, and demonstrate their tradeoffs, strengths and weaknesses., Comment: 7pages,6figures.It has been accepted by PRA
- Published
- 2017
- Full Text
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115. Оцінка можливостей застосування тасітронів в системах електроживлення імпульсних магнетронних розпилюючих систем
- Subjects
impulse magnetron sputtering system ,таситрон ,magnetron sputtering system ,pulsed mode ,МРС ,тасітрон ,tacitron ,импульсный режим питания ,імпульсний режим живлення ,імпульсна МРС ,импульсная МРС - Abstract
Розглянуто переваги імпульсної МРС. Запропоновано використання тасітрону в системах імпульсного живлення МРС. We considered the advantages of impulse magnetron sputtering system. Also, we proposed the use tacitron in pulsed mode impulse magnetron sputtering systems. . Рассмотрено преимущество импульсной МРС. Предложено использование таситронов в системах импульсного питания МРС.
- Published
- 2017
116. An electron gun for physical research
- Author
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Yu. B. Stasevich, A. V. Khudomyasov, E. M. Ladygina, A. V. Kantsyrev, S. M. Savin, V. V. Yanenko, A. V. Bogdanov, R. O. Gavrilin, A. A. Golubev, S. A. Drozdovsky, and A. A. Drozdovsky
- Subjects
Physics ,Nuclear and High Energy Physics ,Radiation ,Pulse duration ,Current amplitude ,Atomic and Molecular Physics, and Optics ,law.invention ,law ,Pulsed mode ,Cold cathode ,Radiology, Nuclear Medicine and imaging ,Atomic physics ,Energy (signal processing) ,Electron gun - Abstract
An electron gun with a cold cathode is developed for physical research with energy to 300 keV. The gun operates in the pulsed mode. Current amplitude is to 100 A, and pulse duration is 100 ns. The first results of the experimental investigation are represented.
- Published
- 2014
117. A study of dynamic Lorentz force detuning of 650MHz βg=0.9 superconducting radiofrequency cavity
- Author
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Vinit Kumar, Abhay Kumar, and Arup Ratan Jana
- Subjects
Physics ,Superconductivity ,Nuclear and High Energy Physics ,High energy ,business.industry ,Bandwidth (signal processing) ,Linear particle accelerator ,Computational physics ,symbols.namesake ,Optics ,symbols ,Physics::Accelerator Physics ,Pulsed mode ,Physics - Accelerator Physics ,business ,Instrumentation ,Lorentz force ,Spallation Neutron Source ,Three dimensional model - Abstract
The small bandwidth of superconducting cavities makes the study of dynamic Lorentz force detuning and its compensation indispensable in case of pulsed mode operation of high gradient accelerators. In this paper, we present the study of this detuning and also propose an optimized design for five cell 650 MHz {\beta}g= 0.9 elliptic superconducting cavities, which will be used in the high energy section of the 1 GeV H- linear accelerator for the proposed Indian Spallation Neutron Source project, by suitably inserting the inter-cell stiffeners. The paper presents a sequential design methodology which starts with study of static Lorentz force detuning and tunability; and progresses to find out the structural modes and related dynamic detuning values by performing transient structural dynamics calculations. The developed methodology is general in nature and can be used for a three dimensional model of any geometry. The work will be useful for optimizing the design against dynamic Lorentz force detuning of superconducting radiofrequency cavities of any shape., Comment: 14 pages, 13 figures
- Published
- 2014
118. A comprehensive study on the inactivation of Escherichia coli under nonthermal technologies: High hydrostatic pressure, pulsed electric fields and ultrasound
- Author
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Barry G. Swanson, Daniela Bermúdez-Aguirre, Abigail Moody, and Gretchen Marx
- Subjects
Chemistry ,business.industry ,Hydrostatic pressure ,Ultrasound ,Analytical chemistry ,Pasteurization ,CELL DEBRIS ,medicine.disease_cause ,law.invention ,Membrane ,law ,Electric field ,medicine ,Pulsed mode ,business ,Escherichia coli ,Food Science ,Biotechnology - Abstract
The inactivation of Escherichia coli under selected treatments using high hydrostatic pressure (HHP), pulsed electric fields (PEF), and ultrasound (US) was studied in apple juice. HHP was carried out from 300 to 600 MPa (0.5–7 min, 21 °C), PEF was applied from 23.07 to 30.76 kV/cm (20–40 °C) using up to 21 pulses, and US was performed in continuous and pulsed mode at 120 μm and temperature from 50 to 60 °C (0–30 min). The best treatment was HHP that inactivated 7 log of bacterial cells in less than 1 min. US also showed positive results (>6 log reduction) after 5 min when temperature was kept at 60 °C regardless of the operation mode. Inactivation with PEF showed about 5 log reduction using the highest electric field strength. The color of the juice showed some changes after processing; the L* value parameter was significantly different (p
- Published
- 2014
119. Beam line parameters for PERC at the ESS
- Author
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Hartmut Abele, Christine Klauser, and T. Soldner
- Subjects
Physics ,Proton ,cold neutrons ,Physics and Astronomy(all) ,Neutron beta decay ,Computational physics ,Standard Model ,Nuclear physics ,Beamline ,Electron radiation ,Proton Electron Radiation Channel ,European Spallation Source ,Pulsed mode ,Physics::Accelerator Physics ,Neutron ,Spallation - Abstract
Precision measurements of correlations in neutron beta decay test the standard model of particle physics. Here, pulsed neutron beams are invaluable to fight systematic effects. We show that the Proton Electron Radiation Channel PERC in pulsed mode is particularly well suited for a long-pulse spallation source, due to its long decay volume. We indicate how the optimum beam line parameters to run PERC at the ESS can be derived and compare the performance with that at the most powerful continuous source, the reactor of the ILL.
- Published
- 2014
120. Limiting parameters of high-power single-stripe laser diodes in the range of 800–808 nm in the pulsed mode
- Author
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V. A. Oleshenko, V. Yu. Bondarev, E. A. Cheshev, Yu. M. Popov, V F Pevtsov, V V Bezotosnyi, and Oleg N Krokhin
- Subjects
Range (particle radiation) ,Materials science ,Computer simulation ,business.industry ,Physics::Optics ,Limiting ,Injection seeder ,Condensed Matter Physics ,Laser ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Power (physics) ,law.invention ,Optics ,law ,Pulsed mode ,Optoelectronics ,business ,Diode - Abstract
Experimental results on the study of the output parameters of high-power continuous-wave (cw) laser diodes operating in the pulsed mode and the results of numerical simulation of the total efficiency of laser diodes with cavity lengths of 3 and 4 mm in a wide range of pump currents are presented. The spectral parameters of the high-power laser diodes are studied at various pulse-repetition rates. The possible causes of the limited output power in the pulsed mode are discussed.
- Published
- 2014
121. The radiation safety education and the pain physicians' efforts to reduce radiation exposure
- Author
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Jae Hun Kim, Seung Wan Hong, Hae Kyoung Kim, Tae Hee Kim, and Nam Sik Woo
- Subjects
medicine.medical_specialty ,Psychological intervention ,030218 nuclear medicine & medical imaging ,Education ,03 medical and health sciences ,0302 clinical medicine ,030202 anesthesiology ,medicine ,Fluoroscopy ,Medical physics ,Radiation protection ,Radiation safety ,Dosimeter ,medicine.diagnostic_test ,business.industry ,Radiation exposure ,Anesthesiology and Pain Medicine ,Emergency medicine ,Pulsed mode ,Safety education ,Original Article ,Interventional pain management ,business ,Pain procedure ,Surveys and questionnaires - Abstract
BACKGROUND C-arm fluoroscopy equipment is important for interventional pain management and can cause radiation injury to physicians and patients. We compared radiation safety education and efforts to reduce the radiation exposure of pain specialists. METHODS A survey of 49 pain specialists was conducted anonymously in 2016. The questionnaire had 16 questions. That questionnaire was about radiation safety knowledge and efforts to reduce exposure. We investigated the correlation between radiation safety education and efforts of radiation protection. We compared the results from 2016 and a published survey from 2011. RESULTS According to the 2016 survey, all respondents used C-arm fluoroscopy in pain interventions. Nineteen respondents (39%) had received radiation safety education. Physicians had insufficient knowledge about radiation safety. When the radiation safety education group and the non-education group are compared, there was no significant difference in efforts to reduce radiation exposure and radiation safety knowledge. When the 2011 and 2016 surveys were compared, the use of low dose mode (P = 0.000) and pulsed mode had increased significantly (P = 0.001). The number checking for damage to radiation protective garments (P = 0.000) and use of the dosimeter had also increased significantly (P = 0.009). But there was no significant difference in other efforts to reduce radiation exposure. CONCLUSIONS Pain physicians seem to lack knowledge of radiation safety and the number of physicians receiving radiation safety education is low. According to this study, education does not lead to practice. Therefore, pain physicians should receive regular radiation safety education and the education should be mandatory.
- Published
- 2016
122. Closure of skin incision by dual wavelength (980 and 1064 nm) laser application
- Author
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Musbahu M. Sani, Abdullahi Ibrahim Uba, Haşim Özgür Tabakoğlu, and Umar A. Abdullahi
- Subjects
Male ,medicine.medical_specialty ,H&E stain ,Dermatology ,01 natural sciences ,law.invention ,010309 optics ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Laser application ,law ,0103 physical sciences ,medicine ,Animals ,Dual wavelength ,Irradiation ,Rats, Wistar ,Skin ,Wound Healing ,Skin incision ,business.industry ,Laser ,Surgery ,Rats ,Dorsal region ,Pulsed mode ,Female ,Laser Therapy ,business ,Biomedical engineering - Abstract
Thermal effect of dual wavelength (980 and 1064 nm) laser application in skin incision closure was assessed on 18 male and female Wister rats. 1-cm-long incisions were made on the shaved dorsal region of 220-250 g animals. The incisions were closed by laser irradiation at 1 W and exposure time, 5 seconds in continuous-wave mode (CW) and 1 W and exposure time, 10 seconds in pulsed mode to deliver total energies of 5 J and 10 J per spot onto the incisions, respectively. Animals from each group were sacrificed at 0th, 4th, and 7th days and the skin samples of the weld area were excised for histological analysis using Hematoxylin and Eosin (HE) stain. Mean thermally altered area (TAA) of CW-mode laser-treated groups was found to increase significantly (p0.05) compared with pulsed mode laser treated group at 0th and 4th days post-irradiation while no significant difference (p0.05) was statistically found at 7th day post-irradiation. Moreover, tighter closure was observed with CW group at 7th day post-irradiation. We thus conclude that 1 W, 5 J for 5 seconds CW mode laser application of 980 and 1064 nm combined beam form in skin incision closure was found to have absolute wound healing capability with minimal thermal alteration.
- Published
- 2016
123. Numerical study of the operating condition effect on the thermal state of the structure of low thruster on oxygen-methane propellant operating in pulsed mode
- Subjects
Propellant ,Engineering ,business.industry ,chemistry.chemical_element ,Oxygen ,Methane ,Cold gas thruster ,chemistry.chemical_compound ,chemistry ,Pulsed mode ,Thermal state ,Pulsed inductive thruster ,Aerospace engineering ,business - Published
- 2016
124. Plasma-Assisted Electrochemical Exfoliation of Graphite in the Pulsed Mode
- Author
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A. G. Krivenko, A. S. Kotkin, and R. A. Manzhos
- Subjects
Chemistry ,02 engineering and technology ,Plasma ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Exfoliation joint ,0104 chemical sciences ,Chemical engineering ,Pulsed mode ,Graphite ,Physical and Theoretical Chemistry ,0210 nano-technology - Published
- 2018
125. Continuous wave operation of InAs-based quantum cascade lasers at 20 μm
- Author
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Alexei N. Baranov, A. Meguekam, H. Nguyen Van, Roland Teissier, Z. Loghmari, Michael Bahriz, Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Composants à Nanostructure pour le moyen infrarouge (NANOMIR), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010302 applied physics ,Materials science ,Threshold current ,Physics and Astronomy (miscellaneous) ,business.industry ,Physics::Optics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,Cladding (fiber optics) ,7. Clean energy ,01 natural sciences ,law.invention ,[SPI]Engineering Sciences [physics] ,Cascade ,law ,Optical cavity ,0103 physical sciences ,[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic ,Pulsed mode ,Continuous wave ,Optoelectronics ,0210 nano-technology ,business ,Quantum - Abstract
International audience; We report low threshold continuous wave (CW) operation of InAs/AlSb quantum cascade lasers emitting around 20 lm. The laser cavity was made of a plasmon-enhanced dielectric waveguide with cladding layers made of n-InAs. The devices exhibited a threshold current density of 1.38 kA/cm 2 at the maximum temperature of CW operation of 240 K and an output power of 14 mW/facet at T ¼ 80 K. In pulsed mode, the lasers operated up to 380 K with a threshold current density of 1.15 kA/cm 2 at room temperature.
- Published
- 2019
126. Room-Temperature Operation of Buffer-Free GaSb–AlGaSb Quantum-Well Diode Lasers Grown on a GaAs Platform Emitting at 1.65 μm.
- Author
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Mehta, M., Jallipalli, A., Tatebayashi, J., Kutty, M.N., Albrecht, A., Balakrishnan, G., Dawson, L.R., and Huffaker, D.L.
- Abstract
Buffer-free growth of GaSb on GaAs using interfacial misfit (IMF) layers may significantly improve the performance of antimonide-based emitters operating between 1.6 and 3 mum by integrating III-As and III-Sb materials. Using the IMF, we are able to demonstrate a GaSb-AlGaSb quantum-well laser grown on a GaAs substrate and emitting at 1.65 mum, the longest known operating wavelength for this type of device. The device operates in the pulsed mode at room temperature and shows 15-mW peak power at -10degC and shows high characteristic temperature (To) for an Sb-based active region. Further improvements to IMF formation can lead to high-performance lasers operating up to 3 mum. [ABSTRACT FROM PUBLISHER]
- Published
- 2007
- Full Text
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127. Gallium dopant-induced tunable electrical properties of reduced graphene oxide using metal organic chemical vapor deposition.
- Author
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Ryu, Beo Deul, Han, Min, Ko, Kang Bok, Cuong, Tran Viet, Lim, Chang-Hyun, Lee, Gun Hee, and Hong, Chang-Hee
- Subjects
- *
METAL organic chemical vapor deposition , *GRAPHENE synthesis , *GRAPHENE oxide , *METALLIC oxides , *INDIUM gallium zinc oxide , *FIELD-effect devices , *GALLIUM - Abstract
• A gallium-doped reduced graphene oxide (Ga-rGO) material by a MOCVD system has been demonstrated. • It is investigated the effect of doping level on Ga bonding in rGO layer controlled via the pulsed mode of doping conditions. • The Dirac point for the Ga-rGO devices shifted in the positive direction towards positive gate voltages on pulsed mode. • The Ga-doped rGO layer demonstrates tunable electrical and structural properties by applying the doping-modulation process. In this study, we develop a gallium-doped reduced graphene oxide (Ga-rGO) material with desirable electrical properties by a metal-organic chemical vapor deposition system using the pulsed mode technique. The effect of doping level on Ga bonding in rGO layer controlled via the pulsed mode of doping conditions, such as dopant source injection and interruption durations, is investigated using the X-ray photoelectron spectroscopy (XPS). The XPS data indicated that the pulsed mode of doping conditions resulted in a higher Ga composition and a larger O–Ga bonding portion in the Ga-rGO layer. Additionally, the Dirac point of Ga-rGO layer with the pulsed mode was observed to shift toward positive voltage in the bottom-gate field effect transistor device, leading to a p -type behavior. The higher work function of Ga-rGO affected the Schottky contact between the Ga-rGO layer and n -type Si leading to lower fermi-energy level in the energy-band structure. Consequently, this work proposes a simplistic approach of Ga doping in graphene materials that can modulate the tunable electrical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
128. Unsteadiness in a ramjet model
- Author
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L. L. Kartovitskii, V. N. Karasev, O. A. Skachkov, V. M. Levin, and E. A. Krymov
- Subjects
Materials science ,General Chemical Engineering ,General Physics and Astronomy ,Energy Engineering and Power Technology ,General Chemistry ,Mechanics ,Combustion ,External flow ,Physics::Fluid Dynamics ,symbols.namesake ,Fuel Technology ,Mach number ,Physics::Space Physics ,Aviation kerosene ,Combustor ,symbols ,Pulsed mode ,Physics::Chemical Physics ,Ramjet ,Physics::Atmospheric and Oceanic Physics - Abstract
The process of combustion of a hydrocarbon fuel in a pulsed mode is discussed on the basis of results of ramjet testing in an external flow modeling a Mach 5 flight.
- Published
- 2013
129. AlInP–AlGaInP Quantum-Well Lasers Grown by Molecular Beam Epitaxy.
- Author
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Tukiainen, A., Toikkanen, L., Haavisto, M., Erojarvi, V., Rimpilainen, V., Viheriala, J., and Pessa, M.
- Abstract
We have examined a possibility to use an AlxIn1-x P layer as an active region of a 650-nm semiconductor laser. Encouraging results have been obtained with compressively strained oxide-stripe AlInP-AlGaInP quantum-well lasers, which operated in continuous-wave mode at room temperature, producing an optical power of 460 and 320 mW per uncoated facet at 10 degC and 20 degC, respectively. In pulsed mode, a power level of 780 mW/facet was achieved at 2-A drive current at 5 degC. The results indicate that wide-bandgap AlInP affords an opportunity to develop lasers for the wavelengths 600leslambdales650 nm, which is difficult to achieve by any semiconductor heterostructure [ABSTRACT FROM PUBLISHER]
- Published
- 2006
- Full Text
- View/download PDF
130. Bound-to-continuum GaInAs-AlAsSb quantum cascade lasers with reduced electric injection power density.
- Author
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Yang, Q., Manz, C., Bronner, W., Schauble, K., Mann, Ch., Schwarz, K., Kohler, K., and Wagner, J.
- Abstract
Short-wavelength (lambda<4 mum) GaInAs-AlAsSb quantum cascade (QC) lasers have been demonstrated using a "bound-to-continuum" design for the purpose of reducing the electric injection power density. As a result, we have reduced the low-temperature electric injection power density of the lasers by 40%, compared to that of GaInAs-AlAsSb QC lasers emitting at the same wavelength but adopting a triple-quantum-well design. The lasers in the present report can operate up to room temperature (300 K) in pulsed mode, emitting at short-wavelength lambda~3.7-3.9 mum [ABSTRACT FROM PUBLISHER]
- Published
- 2006
- Full Text
- View/download PDF
131. High-T0 strain-compensated InGaAsSb-AlGaAsSb quantum-well lasers emitting at 2.43 μm.
- Author
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W. Li, J.B. Heroux, H. Shao, and W.I. Wang
- Abstract
Strain-compensated InGaAsSb-AlGaAsSb quantum-well (QW) lasers emitting near 2.5 μm have been grown by solid-source molecular beam epitaxy. The relatively high arsenic composition causing a tensile strain in the Al0.25GaAs0.08Sb barriers lowers the valence band edge and the hole energy level, leading to an increased hole confinement and improved laser performance. A 60% external differential efficiency in pulsed mode was achieved for 1000-μm-long lasers emitting at 2.43 μm. A characteristic temperature T0 as high as 163 K and a lasing-wavelength temperature dependence of 1.02 nm/°C were obtained at room temperature. For 2000 × 200 μm2 broad-area three-QW lasers without lateral current confinement, a low pulsed threshold of 275 A/cm2 was measured. [ABSTRACT FROM PUBLISHER]
- Published
- 2005
- Full Text
- View/download PDF
132. Type-II interband cascade lasers in the 4.3-4.7-μm wavelength region.
- Author
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R.Q. Yang, C.J. Hill, Baohua Yang, and C.M. Wong
- Abstract
Operation of type-II interband cascade lasers in the 4.3-4.7-μm wavelength region has been demonstrated at temperatures up to 240 K in pulsed mode. These lasers fabricated with 150-μm-wide mesa stripes operated in continuous-wave (CW) mode up to a maximum temperature of 110 K, with an output power exceeding 30 mW/f and a threshold current density of about 41 A/cm2 at 90 K. The maximum CW operation temperature of 110 K is largely limited by the high specific thermal resistance of the 150-μm-wide broad area lasers. A 20-μm-wide mesa stripe laser was able to operate in CW mode at higher temperatures up to 125 K as a result of the reduced specific thermal resistance of a smaller device. [ABSTRACT FROM PUBLISHER]
- Published
- 2004
- Full Text
- View/download PDF
133. Room-temperature 2.81-μm continuous-wave operation of GaInAsSb-AlGaAsSb laser.
- Author
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M. Grau, C. Lin, and M.-C. Amann
- Abstract
GaInAsSb-AlGaAsSb multiple quantum-well (QW) lasers with an emission wavelength of 2.81 μm are reported. The ridge waveguide lasers with highly strained QWs show continuous-wave laser emission up to 25°C; in pulsed mode, the lasers operate up to 60°C. For pulsed operation, a threshold current density of 360 A/cm2 is found for devices with 30-μm stripe width and 2-mm cavity length at room temperature. A low threshold current density at infinite length of 248 A/cm2 is derived. [ABSTRACT FROM PUBLISHER]
- Published
- 2004
- Full Text
- View/download PDF
134. Double-waveguide interband cascade laser with dual-wavelength emission
- Author
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Julian Scheuermann, Robert Weih, Martin Kamp, Sven Höfling, Johannes Koeth, University of St Andrews. Condensed Matter Physics, and University of St Andrews. School of Physics and Astronomy
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,NDAS ,Physics::Optics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,02 engineering and technology ,Interband cascade laser ,01 natural sciences ,Waveguide (optics) ,law.invention ,law ,0103 physical sciences ,Dual wavelength ,QC ,010302 applied physics ,business.industry ,021001 nanoscience & nanotechnology ,Laser ,T Technology ,Power (physics) ,Wavelength ,QC Physics ,Cascade ,Optoelectronics ,Pulsed mode ,0210 nano-technology ,business - Abstract
We are grateful for receiving financial support within the BMBF Project “LASELO” (FKZ: 13N13773). Interband cascade lasers (ICLs) with dual wavelength emission have been realized by utilizing two spatially separated active regions in the same device. The two wavelengths (3.1 and 3.7 µm) were chosen in order to demonstrate that the usual spectral gain bandwidth of an ICL can be overcome. At 20°C, threshold current densities as low as 215 A/cm² (short wavelength) and 158 A/cm² (long wavelength) could be achieved in pulsed mode. It was possible for an epi-up mounted device to maintain dual-wavelength continuous-wave emission up to 0°C. Despite the longer wavelength emission being suppressed at higher temperatures, the shorter wavelength maintained an output power of more than 10 mW at 15°C. Postprint
- Published
- 2018
135. 3 μm InAs quantum well lasers at room temperature on InP
- Author
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Weimin Huang, J.Y. Zhang, Y.J. Ma, G. X. He, Hongmin Huang, Y.H. Shi, W.Y. Ji, Y.G. Zhang, Xingyou Chen, Yi Gu, and Qian Gong
- Subjects
010302 applied physics ,Diffraction ,Photoluminescence ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,Cladding (fiber optics) ,01 natural sciences ,law.invention ,law ,0103 physical sciences ,Pulsed mode ,Optoelectronics ,Quantum well laser ,0210 nano-technology ,business ,Lasing threshold ,Quantum well - Abstract
An InP-based metamorphic InAs quantum well laser has been demonstrated on an In0.8Al0.2As template with electrically pumped lasing up to 3 μm at room temperature. The dual-layer upper cladding structure, consisting of In0.8Al0.2As first cladding and Al0.35Ga0.65As second cladding layers, is applied to enhance the electronic and optical confinements. Despite the lattice-mismatched approach, X-ray diffraction and photoluminescence measurements show a moderate material quality of the active region. By using 15-nm-thick type-I quantum wells, the lasing wavelength has been achieved to be 3.06 μm in the pulsed mode at 300 K and 2.93 μm in the continuous-wave mode at 220 K.
- Published
- 2018
136. Long-wavelength InP-based quantum-dash lasers.
- Author
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Schwertberger, R., Gold, D., Reithmaier, J.P., and Forchel, A.
- Abstract
Self-assembled InAs quantum-dash (QD) lasers with emission wavelengths between 1.54 and 1.78 μm based on the AlGaInAs-AlInAs-InP material system were grown by gas source molecular beam epitaxy. Threshold current densities below 1 kA/cm2 were achieved for 1-mm-long mirror coated broad area lasers with a stack of four QD layers. The devices can be operated up to 80°C in pulsed mode and show a high T0 value of 84 K up to 35°C. In comparison to quantum-well lasers a much lower temperature sensitivity of the emission wavelength was achieved. The temperature shift of Δλ/ΔT = 0.12 nm/K is as low as that caused by the refractive index change [ABSTRACT FROM PUBLISHER]
- Published
- 2002
- Full Text
- View/download PDF
137. An Energy-Efficient IR-UWB Receiver Based on Distributed Pulse Correlator
- Author
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Shang Wang, Yunliang Zhu, Hui Wu, and Jianyun Hu
- Subjects
Engineering ,Radiation ,business.industry ,Transmitter ,Electrical engineering ,Data_CODINGANDINFORMATIONTHEORY ,Condensed Matter Physics ,Chip ,Pulse (physics) ,CMOS ,Hardware_GENERAL ,Electronic engineering ,Pulsed mode ,Electrical and Electronic Engineering ,Circuit complexity ,Transceiver ,business ,Efficient energy use - Abstract
A new circuit technique called distributed pulse correlator (DPC) is proposed for pulse detection in ultra-wideband impulse radio (IR-UWB) receivers. Among several IR-UWB transceiver architectures, an analog correlation receiver has the advantages of good performance and reduced circuit complexity, but requires a correlator and a template pulse with good time resolution. To achieve both fine time resolution and low power consumption, a DPC time-interleaves multiple sampling stages operating in a power-saving pulsed mode and incorporates a built-in mechanism to generate the reconfigurable local template pulse. The operation of the DPC is theoretically analyzed and its performance evaluated, followed by a detailed discussion of its circuit implementation. A chip prototype of a 3–10-GHz analog correlation receiver employing an eight-tap, 10-GSample/s DPC was designed and fabricated in a 0.18- $\mu$ m standard digital CMOS technology. In the measurement, the DPC achieves a pulse rate of 250 MHz with an energy efficiency of 40 pJ/pulse, and the whole receiver achieves an energy efficiency of 190 pJ/pulse at the 250-MHz pulse rate. The complete IR-UWB link (a transmitter, a receiver, and antennas) is also tested.
- Published
- 2013
138. Denervation of the Zygapophysial Joints of the Cervical and Lumbar Spine
- Author
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Stephan Klessinger
- Subjects
Denervation ,medicine.medical_specialty ,Percutaneous ,Painful joints ,business.industry ,Pain relief ,medicine ,Pulsed mode ,Orthopedics and Sports Medicine ,Lumbar spine ,business ,Cryoneurolysis ,Surgery - Abstract
Percutaneous denervation procedures offer pain relief by denervation of the nerves that innervate painful joints. The denervation may be performed by radiofrequency thermoneurolysis using a thermal or a pulsed mode, cryoneurolysis, or laser denervation. Significant publications only exist for radiof
- Published
- 2013
139. Comparison between leaky and pulsed modes of ion extraction from an electron beam ion trap
- Author
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Zhimin Hu, Shunsuke Ohtani, Hirofumi Watanabe, Nobuyuki Nakamura, and Yusuke Ishiguro
- Subjects
Nuclear and High Energy Physics ,Chemistry ,Extraction (chemistry) ,Pulsed mode ,Charge (physics) ,Physics::Atomic Physics ,Atomic physics ,Leaky mode ,Instrumentation ,Measure (mathematics) ,Recombination ,Electron beam ion trap ,Ion - Abstract
We present the charge state distributions of highly charged ions extracted from an electron beam ion trap (EBIT). The distributions were obtained in the two different extraction modes, pulsed mode and leaky mode. The number ratio between adjacent charge state ions, which is an important quantity to measure dielectronic recombination cross sections with an EBIT, is compared between the two extraction modes. The results are also compared with recent theoretical predictions by Zhang et al. [17] .
- Published
- 2013
140. Features of the performance of a transient voltage suppressor in the pulsed mode
- Author
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A. Z. Rahmatov, O. A. Abdulkhaev, D. M. Yodgorova, and A. V. Karimov
- Subjects
Power rating ,Materials science ,business.industry ,Optoelectronics ,Pulse duration ,Pulsed mode ,Condensed Matter Physics ,business ,Transient voltage suppressor ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Abstract
It is experimentally shown that the pulse withstand capacity of transient voltage suppressors, independent of power rating, decreases by the same law with increasing pulse duration, which indicates their optimum design parameters. The interrelation between transition times (turned on and off) and the characteristic parameters of the transient voltage suppressor structure is shown. The possibility of emitting a power fraction at the resonance frequency is an additional stimulus to increasing the withstand power.
- Published
- 2013
141. Modeling and Simulation Methodology for SOA-Aware Circuit Design in DC and Pulsed-Mode Operation of HV MOSFETs
- Author
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Sourabh Khandelwal, Thomas Gneiting, S. Sharma, Yogesh Singh Chauhan, and Tor A. Fjeldly
- Subjects
Engineering ,business.industry ,Circuit design ,Electrical engineering ,Hardware_PERFORMANCEANDRELIABILITY ,Electronic, Optical and Magnetic Materials ,Pulse (physics) ,Modeling and simulation ,MOSFET ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Pulsed mode ,Transient (oscillation) ,Electrical and Electronic Engineering ,business ,Electronic circuit - Abstract
In this paper, we present a modeling and simulation methodology for safe-operating-area (SOA)-aware circuit design in dc and pulsed-mode operation of high-voltage MOSFETs (HV MOSFETs). The developed methodology gives an accurate description of the SOA of devices under dc and, more importantly, transient inputs, taking into account the width and duty-cycle of the pulse. To the best of the authors' knowledge, this is the first time such a methodology integrated with circuit design tools is presented. It is shown through simulation of standard circuits of HV MOSFETs that the proposed methodology avoids overdesigns and enables circuit designers to use the high-voltage technology to its full potential.
- Published
- 2013
142. Influence of air abrasion tips and operation modes on enamel-cutting characteristics
- Author
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Tereza Cristina Dias, Lourdes Aparecida Martins dos Santos-Pinto, Cláudia Maria de Souza Peruchi, Ary dos Santos-Pinto, Ana Carolina Mascarenhas Oliveira, Catholic University of Brasilia, Universidade Estadual Paulista (Unesp), Universidade Federal de São Carlos (UFSCar), and Universidade Federal de Sergipe (UFS)
- Subjects
Materials science ,Atmospheric pressure ,Enamel paint ,business.industry ,Bar (music) ,Dental air abrasion ,Conservative dentistry ,Dentistry ,Articles ,symbols.namesake ,Dental cavity preparation ,Mach number ,Air abrasion ,visual_art ,visual_art.visual_art_medium ,symbols ,Inner diameter ,Pulsed mode ,dental cavity preparation ,Composite material ,business ,General Dentistry ,conservative dentistry ,Aluminum oxide - Abstract
Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:28:43Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:48:17Z : No. of bitstreams: 1 2-s2.0-84875247256.pdf: 100983 bytes, checksum: 80ed07a04fa708be270f70e1b1efd827 (MD5) Made available in DSpace on 2014-05-27T11:28:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-26 Objective: To assess the influence of air abrasion tips and system operation modes on enamel cutting. Methods: Forty bovine teeth were abraded with the air abrasion system Mach 4.1 for 10 and 15 seconds, employing conventional and sonic tips of 0.45-mm inner diameter and a 90° angle, and 27.5-μm aluminum oxide at 5.51 bar air pressure in continuous and pulsed modes. The width and depth of the resulting cuts were measured in SEM. Results: The multivariate analysis of variances revealed that, compared to the sonic tip, the conventional tip produced shallower cuts independent of the operation mode and the application period. Conclusions: The cutting patterns observed in this study suggest that the pulsed mode produced deeper cuts when both the conventional and sonic tips were used, and that the sonic tip cut more dental tissue than the conventional one. Department of Pediatric Dentistry Catholic University of Brasilia Department of Pediatric Dentistry and Orthodontics Araraquara Dental School Sao Paulo State University (UNESP) Department of Statistics Federal University of Sao Carlos (UFSCar) Department of Health Education Federal University of Sergipe Department of Pediatric Dentistry and Orthodontics Araraquara Dental School Sao Paulo State University (UNESP)
- Published
- 2013
143. Thulium-YAG laser sialendoscopy for parotid and submandibular sialolithiasis
- Author
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Francis Marchal, F. Disant, M. Durbec, S. Vigier, E. Dinkel, and Frédéric Faure
- Subjects
Adult ,Male ,medicine.medical_specialty ,Thulium-YAG laser ,Adolescent ,Lasers, Solid-State ,Dermatology ,law.invention ,Young Adult ,law ,Submandibular Gland Diseases ,medicine ,Humans ,Power output ,Child ,Submandibular sialolithiasis ,Aged ,Retrospective Studies ,Salivary Gland Calculi ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Endoscopy ,Middle Aged ,Lithotripsy, Laser ,Laser ,Surgery ,Treatment Outcome ,Child, Preschool ,Thulium ,Pulsed mode ,Female ,Parotid Diseases ,Nuclear medicine ,business ,Follow-Up Studies - Abstract
Objective To evaluate the efficacy and safety of thulium-YAG laser in sialendoscopic fragmentation of salivary lithiasis. Design Retrospective, interventional case series. Material Sixty-three patients treated by interventional sialendoscopy with thulium-Yag laser fragmentation between 2003 and 2010 at Edouard Herriot Hospital were included in the study. The laser was used for non-floating or large lithiasis (>4 mm). Methods The sialendoscopic thulium fiber laser was used in a pulsed mode with an average power output of 2–8 W to fragment and facilitate extraction of salivary stones. Several variables were studied: success rate, total number of procedures, total energy per procedure, size and number of salivary stones removed, and complications. Results Our series of 63 cases includes 40 cases of parotid lithiasis and 23 cases of submandibular lithiasis. In nine cases, two sessions of laser were performed. Stone size was evaluated pre-operatively by ultrasound and varied between 2 and 18 mm. Laser fragmentation was possible in every case. Complete extraction of the lithiasis was possible in 51 cases (73.9%) and partial extraction in eight cases (12.6%). Extraction failed in four cases (6.3%). Mean stone size was 5.4 mm (5.7 mm for parotid glands and 5.0 mm for sub-mandibular glands) and mean energy per procedure was 1,450 J (range: 1,400–1,800 J). Ductal perforations were observed in 12.7% of the cases. 65.1% of patients were free of symptoms with a mean follow-up of 18 months. Conclusion Thulium-YAG laser appears to be an effective and safe technique in the treatment of salivary lithiasis. Lasers Surg. Med. 44: 783–786, 2012. © 2012 Wiley Periodicals, Inc.
- Published
- 2012
144. Analysis of thermal therapy using infrared diode lasers operated in continuous wave and pulsed mode
- Author
-
Jui-Teng Lin
- Subjects
Materials science ,business.industry ,Infrared ,law ,Optoelectronics ,Pulsed mode ,Continuous wave ,Thermal therapy ,business ,Laser ,Diode ,law.invention - Published
- 2016
145. In vitro histological evaluation of the surgical margins made by different laser wavelengths in tongue tissues
- Author
-
J. A. Suárez-Quintanilla, Fernanda Garces, Maria-Leonor Delgado, Fernando Ferreira, Luís-Silva Monteiro, Marco Antonio Trevizani Martins, Ana-Salvaterra Azevedo, and Sofia Carreira
- Subjects
medicine.medical_specialty ,Materials science ,Odontología ,Oral cavity ,law.invention ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,law ,Tongue ,medicine ,Oral mucosa ,General Dentistry ,Research ,Histopathological analysis ,Soft tissue ,030206 dentistry ,Laser ,Ciencias de la salud ,Surgery ,Wavelength ,medicine.anatomical_structure ,UNESCO::CIENCIAS MÃ DICAS ,Pulsed mode ,CIENCIAS MÃ DICAS [UNESCO] ,Oral Surgery ,Biomedical engineering - Abstract
Background: Lasers have become standard tools for the surgical treatment of oral lesions. The purpose of this study is to determine the surgical margins and histologically evaluate the tissue thermal effects induced by different types of surgical instruments. Material and Methods: Cuts were made in pork tonguesâ mucosa with different lasers (Er:YAG at 2W with and without air / water spray and at 4W with and without air / water spray; CO2 at 3.5W and 7W in pulsed mode and at 7W in continuous mode; the diode laser at 3.5W and boost 3.5W in pulsed mode; Nd:YAG at 6W, 40Hz and electroscalpel at 5W and conventional scalpel as control. Macroscopic and microscopic morphological changes were evaluated. Results: The results of this study showed that the surgical instruments that caused greater tissue damage extension were: the Nd:YAG laser (670.68μm), the diode 3.5W and boost PW (626.82μm), the CO2 7W CW (571.18μm), the CO2 at 7W PW (485.45μm), the diode 3.5W PW (456.15μm), the electroscalpel (409.57μm) and lastly the CO2 laser 3.5W PW (306.19μm) and Er:YAG (74.66μm) laser, regardless of power, mode or air / water spray used. An association between the Tissue Damage Extension and the Degree of Carbonization (r = 0.789; P = 0.01), and an association between the Tissue Damage Extension and Regularity of the Incision were found (r = -, 299; P = 0.01). Conclusions: The results of this study suggest that lasers can be used in soft tissues biopsies of the oral cavity, enabling a correct histopathological analysis, as long as the biological effects of each laser type are considered. The Er:YAG laser revealed its potential for biopsies of the oral mucosa ensuring a successful histological evaluation and the CO2 laser at 3,5W in pulsed mode presented itself as the best choice for surgeries with hemostasis.
- Published
- 2016
146. Behavior of Natural Organic Matter(NOM), Chlorine Residual, and Disinfection By-Products(DBPs) Formation in Pulsed UV Treated Water
- Author
-
Jihee Han and Jinsik Sohn
- Subjects
Pollutant ,Residual chlorine ,Treated water ,Chemistry ,Environmental chemistry ,Peak intensity ,Chlorine ,chemistry.chemical_element ,Pulsed mode ,Sewage treatment ,sense organs ,Natural organic matter - Abstract
UV technology is widely used in water and wastewater treatment. Many researches have been conducted on microbial disinfection and micro pollutant reduction with UV treatment. However, the study on NOM with UV has limited because low/medium pressure UV lamp is not sufficient to affect refractory organics such as NOM. Pulsed UV treatment using UV flash lamp can be operated in the pulsed mode with much greater peak intensity. The pulse duration is typically in microseconds, whereas the interval between pulses is in the order of milliseconds. The high intensity of pulsed UV would mineralize NOM itself as well as change the characteristics of NOM. Chlorine demand and DBPs formation is affected on the changed amounts and properties of NOM. The objective of this study is to investigate the effect on NOM, chlorine residual, and chlorinated DBPs formation with pulsed UV treatment.
- Published
- 2012
147. The Possibilities of Applying QCM Method in Pulsed Mode for Investigating the Adsorption Dynamics of Volatile Compounds on Finely Dispersed Sorbents
- Author
-
Aleksei P. Filippov
- Subjects
Sorbent ,Chemistry ,General Chemical Engineering ,lcsh:QD450-801 ,Flow cell ,lcsh:Physical and theoretical chemistry ,Nanotechnology ,Surfaces and Interfaces ,General Chemistry ,Quartz crystal microbalance ,Piezoelectric quartz ,Metal ,Resonator ,Adsorption ,visual_art ,visual_art.visual_art_medium ,Pulsed mode - Abstract
In this study, the possibilities of applying quartz crystal microbalance (QCM) method in pulsed mode for investigating the adsorption dynamics of volatile compounds on finely dispersed sorbents is shown. The use of piezoelectric quartz resonator (PQR) sensors with chemical coverings on the base of metal stearates or thiolates, as well as other low-inertia sensors is proposed to evaluate the concentration of gas-phase sorbate current in the flow cell of electronic nose–type sensors. These sensors are placed in the cell in parallel to the PQR with a sorbent under investigation.
- Published
- 2012
148. Inactivation of Saccharomyces cerevisiae in pineapple, grape and cranberry juices under pulsed and continuous thermo-sonication treatments
- Author
-
Gustavo V. Barbosa-Cánovas and Daniela Bermúdez-Aguirre
- Subjects
biology ,Chemistry ,Sonication ,Saccharomyces cerevisiae ,CRANBERRY JUICE ,Gompertz function ,Acoustic energy ,Pasteurization ,Continuous mode ,biology.organism_classification ,law.invention ,food ,law ,Pulsed mode ,Food science ,food.beverage ,Food Science - Abstract
Pineapple, grape and cranberry juice were thermo-sonicated (24 kHz, 400 W, 120 μm) at 40 °C, 50 °C and 60 °C during 10 min at continuous and pulsed mode. Inactivation of Saccharomyces cerevisiae was tested from 0 to 10 min; color and pH were measured. Survivor’s curves were fitted with Weibull distribution, four parameter model and modified Gompertz equation. The acoustic energy (AE) was also calculated. S. cerevisiae was inactivated in the treatments at 60 °C, with the continuous mode being more effective. Grape juice showed total inactivation (7-log) after 10 min. Results showed that pH and color changed significantly ( p
- Published
- 2012
149. The Bactericidal Effect of 2780 and 940 nm Laser Irradiation on Enterococcus faecalis in Bovine Root Dentin Slices of Different Thicknesses
- Author
-
Georg Conrads, Tamara Sardar Al-Karadaghi, Mohammed Abbood Al-Maliky, Rene Franzen, and Norbert Gutknecht
- Subjects
0301 basic medicine ,030103 biophysics ,Materials science ,Root canal ,Biomedical Engineering ,Colony Count, Microbial ,Dentistry ,Lasers, Solid-State ,Root dentin ,Enterococcus faecalis ,law.invention ,Tissue Culture Techniques ,03 medical and health sciences ,law ,Dentin ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Irradiation ,biology ,business.industry ,biology.organism_classification ,Bactericidal effect ,Laser ,medicine.anatomical_structure ,Pulsed mode ,Cattle ,Lasers, Semiconductor ,business ,Nuclear chemistry - Abstract
The aim of this in vitro study was to investigate the antibacterial effect of the dual wavelength (2780 nm Er,Cr:YSGG and 940 nm diode) laser in elimination of Enterococcus faecalis in comparison with a 2780 nm Er,Cr:YSGG laser alone.Various laser wavelengths have been introduced as an adjunct in root canal treatment because of laser's bactericidal effect.Seventy- five slices of dentin with thicknesses of 300, 500, and 1000 μm (n = 25 each) obtained from caries-free bovine teeth were inoculated with 1 μL of E. faecalis suspension [1.67 × 10(7) colony-forming units (CFU)] and divided randomly into three groups: (A) samples indirectly irradiated with power settings of 1.06 W, 50 Hz, and 50 μs for Er,Cr:YSGG laser; (B) samples indirectly irradiated with Er,Cr:YSGG laser with the same power settings as group A and simultaneously with a 940 nm diode laser of 0.51 W in pulsed mode; and five samples from each thickness that were chosen as an unirradiated control group (Co). After irradiation, the CFU of E. faecalis were counted and the bacterial reduction was analyzed using Kruskal-Wallis nonparametric and post-hoc Dunnett tests.There were statistical differences between groups A and B compared with the control group over all the three dentin slice thicknesses (p 0.001). However, there was no statistical difference between groups A and B in killing of E. faecalis on 500 μm dentin slices. There were significantly more viable bacteria in group A than in group B in 300 and 1000 μm dentin slices (p 0.01).The results of this in vitro study showed that the dual wavelength laser system obtained a significantly higher bactericidal effect on E. faecalis than Er,Cr:YSGG laser, reaching a depth of 1000 μm of dentin.
- Published
- 2015
150. INTELLECTUAL TWO-LEVEL SYSTEM OF ELECTRONIC WARFARE WITH UAVs
- Author
-
O. Yu. Tkachenko and V. M. Sineglazov
- Subjects
Work (electrical) ,Interference (communication) ,Computer science ,business.industry ,Broadband ,Electrical engineering ,Pulsed mode ,Electronic warfare ,business - Abstract
This work represents an algorithm of development of broadband interference source for theunmanned aerial vehicles. The configuration of device is implemented by an intellectual unit, which providesremote turn-on of the generators that ensures a pulsed mode of the system
- Published
- 2015
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