Статті в журналах: "Pulsed mode"

1

Flood, C. J., G. Giuliani, and H. M. van Driel. "Pulsed electro-optic modulation for efficient, active continuous-wave laser mode-locking." Canadian Journal of Physics 71, no. 1-2 (January 1, 1993): 1–4. http://dx.doi.org/10.1139/p93-001.

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We demonstrated efficient active mode-locking of a Nd:YAG laser using broad bandwidth, pulsed electro-optic modulation. A 10 GHz, LiTaO3 traveling wave phase modulator, driven by 300 ps FWHM electrical pulses with less than 1 mW of drive power, was used to generate detector-limited, mode-locked laser pulses of less than 50 ps duration at 76 MHz. Shorter modulator drive pulses are possible and near bandwidth-limited mode-locked pulses should be attainable. The use of pulsed modulation rather than conventional sinusoidal modulation permits both pulse width and pulse build-up time reductions and generally makes active mode-locking competitive with passive mode-locking for relatively low-gain and narrow-bandwidth lasers.

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2

Miraval Zanon, A., F. Ambrosino, F. Coti Zelati, S. Campana, A. Papitto, G. Illiano, G. L. Israel, L. Stella, P. D’Avanzo, and M. C. Baglio. "UV and X-ray pulse amplitude variability in the transitional millisecond pulsar PSR J1023+0038." Astronomy & Astrophysics 660 (April 2022): A63. http://dx.doi.org/10.1051/0004-6361/202243180.

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The transitional millisecond pulsar PSR J1023+0038 is the first millisecond pulsar discovered to emit UV and optical pulses. Here we present the results of the UV and X-ray phase-resolved timing analysis of observations performed with the Hubble Space Telescope, XMM-Newton, and NuSTAR satellites between 2014 and 2021. Ultraviolet pulsations are detected in the high luminosity mode and disappear during low and flaring modes, similar to what is observed in the X-ray band. In the high mode, we find variability in both the UV and X-ray pulse amplitudes. The root mean square pulsed amplitude in the UV band ranges from ~2.1% down to ~0.7%, while it oscillates in the interval 5.5–12% in the X-ray band. As also observed in the optical band, this variability is not correlated with the orbital phase. Notwithstanding the rather low statistics, we have marginal evidence that variations in the pulse amplitude do not occur simultaneously in the UV and X-ray bands. When the UV pulsed amplitude decreases below the detection threshold, no significant variation in the X-ray pulsed amplitude is observed. These oscillations in the pulse amplitude could be caused by small random variations in the mass accretion rate leading to a variation in the size of the intra-binary shock region. Finally, we find that the pulsed flux spectral distribution from the X-ray to the UV band is well fitted using a power-law relation of the form νFνpulsed∼ν0.4. This supports the hypothesis of a common physical mechanism underlying the X-ray, UV, and optical pulsed emissions in PSR J1023+0038.

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3

Shemyakin, A. N., M. Yu Rachkov, N. G. Solov’ev та M. Yu Yakimov. "Radiation Power Control of the Industrial CO₂ Laser Excited by а Nonself-Sustained Glow Discharge by Changing the Frequency of Ionization Pulses". Mekhatronika, Avtomatizatsiya, Upravlenie 21, № 4 (11 квітня 2020): 224–31. http://dx.doi.org/10.17587/mau.21.224-231.

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The article describes radiation power control of industrial CO2 lasers of Lantan series excited by а nonself-sustained glow discharge in the automatic mode. These lasers are closed-cycle fast gas-transport lasers excited by a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge. In this case, ionization and conductivity are provided by periodic-pulsed capacitively coupled discharge. The energy contribution to molecular oscillations is provided by the passage of the main discharge current through the plasma with electron density given by ionization. This permits easy laser power control, provides excellent optical homogeneity and stability of an active volume together with high laser efficiency. A system of a nonself-sustained glow discharge with ionization by periodic-pulsed capacitively coupled auxiliary discharge, the stages of creation and brief characteristics of the Lantan series lasers is presented. The method of controlling the power of laser radiation by changing the frequency of the ionization pulses is determined. This control method allows operating of the laser in continuous and in pulse-periodic modes with adjustable pulse ratio and pulse duration, and also provides switching from one mode to another. In the continuous mode, the radiation power is controlled by changing the frequency of ionization pulses, which are high voltage pulses with duration of 100 ns, given with the frequency of 1-5 kHz. Pulse-periodic radiation control is performed by modulating ionization pulses that consists of pulses being delivered in batches. The frequency of the pulses in a batch determines the radiation power in a pulse. The frequency of the batches following is the frequency of the pulse mode, and the length of the batch determines the pulses duration. Based on the experimental data, the dependence of the radiation power on the ionization pulses frequency was determined. An experimental system is presented and the measuring accuracy of the laser radiation power and the frequency of ionization pulses is determined. Data acquiring and processing of experimental results were performed using the NI 6008 USB data acquisition device in the LabVIEW programs of National Instruments. To study the dependence of the laser power on Мехатроника, автоматизация, управление, Том 21, № 4, 2020 231 the frequency of the ionization pulses, a regression analysis method was applied. Studies have shown that the dependence of the laser power on the ionization pulses frequency is linear in a wide range of parameters. The equation of the direct regression is calculated. The confidence estimates of the coefficients of the direct regression and the confidence estimates of the deviation of the theoretical direct regression from the empirical one are calculated with a confidence level of 95%.

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4

Tingting Lu, Tingting Lu, Juntao Wang Juntao Wang, Xiaolei Zhu Xiaolei Zhu, Ren Zhu Ren Zhu, Huaguo Zang Huaguo Zang, and Weibiao Chen Weibiao Chen. "Highly efficient single longitudinal mode-pulsed green laser." Chinese Optics Letters 11, no. 5 (2013): 051402–51404. http://dx.doi.org/10.3788/col201311.051402.

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5

Kokovin, A. O., A. V. Kozyrev, and V. Yu Kozhevnikov. "Simulation of negative corona discharge in atmospheric air: from mode of Trichel pulses to stationary discharge." Journal of Physics: Conference Series 2064, no. 1 (November 1, 2021): 012024. http://dx.doi.org/10.1088/1742-6596/2064/1/012024.

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Abstract The paper presents a 2D multi-fluid non-stationary model of a negative corona discharge in atmospheric-pressure air in the needle-to-plane diode. Discharges were simulated in gaps up to 1 cm with an applied voltage in the range of 8-100 kV. The simulation results demonstrate two stages of the discharge evolution: a pulsed-periodic stage called the Trichel pulses mode and a stationary glow discharge mode. The spatio-temporal distributions of the discharge plasma and electric field are shown in detail. Physical mechanism of Trichel pulses formation and transition to the stationary discharge are also revealed. The duration of the Trichel pulse mode gradually decreases with increasing of the applied voltage.

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6

Kandratsyeu, Aleh, Uladzimir Sabaleuski, Luis Redondo, and Andrei G. Pakhomov. "Four Channel 6.5 kV, 65 A, 100 ns–100 µs Generator with Advanced Control of Pulse and Burst Protocols for Biomedical and Biotechnological Applications." Applied Sciences 11, no. 24 (December 11, 2021): 11782. http://dx.doi.org/10.3390/app112411782.

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Pulsed electric fields in the sub-microsecond range are being increasingly used in biomedical and biotechnology applications, where the demand for high-voltage and high-frequency pulse generators with enhanced performance and pulse flexibility is pushing the limits of pulse power solid state technology. In the scope of this article, a new pulsed generator, which includes four independent MOSFET based Marx modulators, operating individually or combined, controlled from a computer user interface, is described. The generator is capable of applying different pulse shapes, from unipolar to bipolar pulses into biological loads, in symmetric and asymmetric modes, with voltages up to 6.5 kV and currents up to 65 A, in pulse widths from 100 ns to 100 µs, including short-circuit protection, current and voltage monitoring. This new scientific tool can open new research possibility due to the flexibility it provides in pulse generation, particularly in adjusting pulse width, polarity, and amplitude from pulse-to-pulse. It also permits operating in burst mode up to 5 MHz in four independent channels, for example in the application of synchronized asymmetric bipolar pulses, which is shown together with other characteristics of the generator.

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7

Bostanjoglo, O., F. Heinricht, and F. Wünsch. "Performance of A Laser-Pulsed Thermal Electron Gun." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 1 (August 12, 1990): 124–25. http://dx.doi.org/10.1017/s0424820100179373.

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High-speed electron microscopy strongly demands a high-brightness electron gun in order to increase the number of image forming electrons. A few years ago, a laser-pulsed high-brightness electron gun was introduced. Fig.1 shows the experimental set-up, A standard triode system was supplemented with a Nd:YAG laser, focussing optics and a modified anode, which incorporates the laser deflection mirror. The frequency doubled laser pulse (τ =5 ns, λ = 532 nm) is focused through a window onto the tip of the tungsten hairpin emitter. The laser treated area (≈ 100 μm diameter) is heated well above the melting point, which results in a strong thermal electron emission. Due to rapid heat-up and fast cool-down of the tungsten surface short electron pulses with a duration of 20 ns and a maximum current of 20 mA at 80 kV are emitted. A destruction of the tungsten wire is avoided, too. Laser energies used for the generation of electron pulses are in the range of 100 μJ. Due to these minor modification, the DC operation of the electron gun is not disabled, which allows a convenient adjustment in the DC mode and then switching into the pulsed operation mode. Fig.2 shows a typical electron pulse emitted by the gun. Shorter electron pulses up to 5 ns can be generated by a beam blanking unit.

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8

Giner, J., V. Gimeno, G. V. Barbosa-Cánovas, and O. Martín. "Effects of Pulsed Electric Field Processing on Apple and Pear Polyphenoloxidases." Food Science and Technology International 7, no. 4 (August 2001): 339–45. http://dx.doi.org/10.1106/mj46-8j9u-1h11-t0ml.

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The feasibility of inhibiting polyphenoloxidase from apple and pear by pulsed electric field processing was evaluated. These treatments significantly lowered polyphenoloxidase activity of enzyme extracts from apple ( Golden deliciousvar.) and pear ( Blanquillavar.). Exponential decay pulses were generated by a laboratory scale electric pulse generator and applied in bipolar mode. Pulse duration was 0.02 ms and electric field intensities were up to 24.6 kV/cm. The temperature of samples never exceeded 15 ºC during pulsed electric field processing treatments. Polyphenoloxidase activities were reduced up to 3.15% and 38.0% initial value in apple extract at 24.6 kV/cm and pear extract at 22.3 kV/cm both for 6 ms total treatment time, respectively. Apple and pear polyphenoloxidase exposed to pulsed electric field processing diminishes their activities following first order kinetics. Rate constants ranged from 132 to 440 ms 1 for apple polyphenoloxidase, whereas for pear 1 and changed exponentially with the applied electric field intensity. Residual polyphenoloxidase activity was correlated to energy density by an exponential decay model.

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9

Holzwarth, Michael J., Alexander M. Gigler, and Othmar Marti. "Digital Pulsed Force Mode." Imaging & Microscopy 8, no. 4 (November 2006): 37–38. http://dx.doi.org/10.1002/imic.200790065.

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10

Fischer, Baruch, Boris Vodonos, Shimie Atkins, and Alexander Bekker. "Dispersion-mode pulsed laser." Optics Letters 25, no. 10 (May 15, 2000): 728. http://dx.doi.org/10.1364/ol.25.000728.

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11

Gribacheva, V., and S. Shcherbakov. "THE COOLING SYSTEM OF THE PERIODIC PULSED REACTOR." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2021, no. 2 (June 26, 2021): 256–67. http://dx.doi.org/10.55176/2414-1038-2021-2-256-267.

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The paper proposes the configuration and composition equipment of the cooling system of the designed periodic pulsed reactor (PPR) of high power. The special features of the PPR are a small flow section, a large heating of the coolant in the power pulse and the impossibility of useful use of thermal energy in the periodic mode of operation. Liquid lithium is proposed as a coolant and heat is discharged through air heat exchangers (AHE). The goal was to achieve compactness and low power consumption, the ability to work with frequent stops and optimize the operation of equipment in pulse modes. For this purpose, high-temperature AHE with a small heat exchange surface and forced air cooling are used, the circulation circuit is divided into two parts - the reactor circuit and the AHE circuit with two circulation pumps and a common drain tank. The separation of the circuit allows to independently perform the operations of starting, stopping and heating the circuits in a periodic mode. The drain tank limits the composition of the equipment exposed to temperature pulses. Numerical studies of the temperature regime of the coolant in the equipment of the PDR cooling system are carried out. The calculations were performed using the TURBOFLOW code in two-dimensional terms for all the main elements of the equipment. Quasi-stationary (nominal and partial power levels) and pulse modes of operation are considered. Calculated characteristics for forced and natural air circulation are obtained. The limits of the air circulation modes under the conditions of non-freezing of the coolant are determined. The obtained values of the maximum temperatures of the coolant: in the pulsed mode is 750 °C, in the quasi-stationary mode - 490 °C with an average power of 15 MW, air flow of 150 m3/s and the size of the AHE in the plan of 5×5 m, 100 panels of 1.08×0.025×5 m.

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12

Joshi, Bhal Chandra. "On sub-pulse drift related profile mode-changes studied with a new technique." Proceedings of the International Astronomical Union 13, S337 (September 2017): 350–51. http://dx.doi.org/10.1017/s1743921317010316.

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AbstractSub-pulse drift related profile mode-changes provide a useful probe of pulsar radio emission. Measurements on modal profiles of PSRs B0031–07, J1822–2256 and B2319+60 are presented for different drift modes in this communication. The width of profile increases with the drift rate, while no such trend is seen for the pulsed flux density for all these pulsars. A brief discussion of implications for models is presented.

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13

Chernyshova, O. V., T. B. Yelemessov, and D. V. Drobot. "Application of pulse current for dissolution of heat-resistant GS32-VI alloy." Fine Chemical Technologies 16, no. 5 (November 28, 2021): 438–47. http://dx.doi.org/10.32362/2410-6593-2021-16-5-438-447.

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Objectives. To identify the regularities of electrochemical processing of the heat-resistant GS32-VI alloy in a sulfuric acid electrolyte with a concentration of 100 g/dm3 under the action of a pulsed current in a pulsed mode.Methods. Using the electrochemical technological complex EHK-1012 (developed by IP Tetran) and a non-compensatory method of measuring potential, polarization and depolarization curves with a change in pulse duration and a pause between them were recorded. The current pulses had an amplitude ranging from 0 to 3.5 A (when recording the polarization and depolarization curves), pulse durations ranging from 200 to 1200 ms, and a pause (delay) between pulses ranging from 50 to 500 ms. There were no reverse current pulses.Results. The parameters of the current program that provide the maximum values of the alloy dissolution rate and current output were determined: with a current pulse amplitude of 2 A, a current pulse duration of 500 ms, and a pause duration between pulses of 250 ms, the maximum dissolution rate of the alloy is 0.048 g/h·cm2, while the current output for nickel is 61.6% with an anode area of 10 cm2. The basic technological scheme for processing the heat-resistant GS32-VI alloy, which includes anodic alloy dissolution in a pulsed mode, is proposed.Conclusions. Electrochemical dissolution of GS32-VI alloy under pulsed current action results in an optimal dissolution rate ratio of the alloy components, ensuring the production of a cathode precipitate with a total nickel and cobalt content of 97.5%.

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14

Butylskii, Dmitrii, Ilya Moroz, Kseniya Tsygurina, and Semyon Mareev. "Effect of Surface Inhomogeneity of Ion-Exchange Membranes on the Mass Transfer Efficiency in Pulsed Electric Field Modes." Membranes 10, no. 3 (March 11, 2020): 40. http://dx.doi.org/10.3390/membranes10030040.

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Despite the growing interest in pulsed electric field modes in membrane separation processes, there are currently not many works devoted to studying the effect of the surface properties and composition of ion-exchange membranes on their efficiency in these modes. In this paper, we have shown the effect of increasing mass transfer using different kinds of ion-exchange membranes (heterogeneous and homogeneous with smooth, undulated, and rough surfaces) during electrodialysis in the pulsed electric field modes at underlimiting and overlimiting currents. It was found that the maximum increment in the average current is achieved when the average potential corresponds to the right-hand edge of the limiting current plateau of the voltammetric curve, i.e., at the maximum resistance of the system in the DC mode. For the first time, the development of electroconvective vortices was visualized in pulsed electric field modes and it was experimentally shown that even at relatively low frequencies, a non-uniform concentration field is preserved at the time of a pause, which stimulates the rapid development of electroconvection when pulses are switched on again. In the case of relatively high pulse frequencies, the electroconvective vortices formed during a pulse lapse do not completely decay during a pause; they only slightly decrease in size.

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15

Анищенко, И. В., С. В. Покровский, М. А. Осипов, Д. А. Абин, Д. И. Грицаенко та И. А. Руднев. "Неравновесные состояния в ВТСП-композитах второго поколения при сверхкритических импульсных токовых воздействиях". Письма в журнал технической физики 47, № 19 (2021): 22. http://dx.doi.org/10.21883/pjtf.2021.19.51508.18828.

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This paper presents the results of studying the processes of еру HTS composites switching from the superconducting to the resistive state at microsecond current pulses. Two modes of pulsed current load were used: with an amplitude of ~ 1.1 Ic (the so-called "soft" mode) and with an amplitude of ~ 3 Ic ("hard" mode). The possibility of passing supercritical currents through the tape without superconductor characteristics degradation is shown. To explain the processes occurring in the tape during the current pulse, 2D FEA (finite element analyzes) was developed, with the help of which the dynamic resistance of the HTS composite superconducting layer was calculated in the "hard" load mode and nonstationary processes of current redistribution between the different tape layers were demonstrated.

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16

Naidis, G. V., and N. Yu Babaeva. "Modeling of repetitively pulsed low-pressure CO₂ discharges." Physics of Plasmas 29, no. 4 (April 2022): 044501. http://dx.doi.org/10.1063/5.0087197.

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A model of repetitively pulsed low-pressure CO2 discharges is developed. In the framework of this model, plasma characteristics (electric field, electron density, gas temperature, and vibrational temperature of the asymmetric mode) are calculated both during the pulses and in the afterglow periods. The CO2 conversion factor in repetitively pulsed discharges is calculated. Results of computation of plasma parameters and of the conversion factor agree with available experimental data.

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17

Godun, D. V., S. V. Bordusau, and G. P. Budzko. "Output Current Control System of a High Voltage Electric Pulse Generator for Plasma Excitation." PLASMA PHYSICS AND TECHNOLOGY 6, no. 1 (2019): 7–9. http://dx.doi.org/10.14311/ppt.2019.1.7.

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A control and pulse discharge current limiting system integrated into an AC/DC converter and pulse modulator of a high voltage pulse generator have been developed. The peculiarity of such system\textquotesingle s operation is the stabilization of the power supplied to the discharge and the correction of the width of output electric pulses towards decrease upon reaching the specified pulsed current amplitude value. The system enables the pulse generator to work in the modes close to the ``short circuited load'' mode. In this case the driving module of a composite IGBT key performs the correction of the working pulse width and blocks the pulse generator operation if needed. The suggested circuit design solutions allow using the generator in a wide range of electric plasma-forming parameters' modes and working with various types of vacuum gas discharge systems.

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18

Ivankov, Anton S., Anastasia M. Kozhevnikova, Dmitry V. Schitz, and Igor V. Alekseenko. "Investigation of Nonthermal Plasma Jet Excitation Mode and Optical Assessment of Its Electron Concentration." Applied Sciences 11, no. 19 (October 3, 2021): 9203. http://dx.doi.org/10.3390/app11199203.

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The results of a study of a plasma jet of atmospheric-pressure helium driven by a capacitive discharge using sine and pulsed modes of excitation are presented. The homogeneous discharge of a multi-channel plasma jet at gas temperature of 34 °C and helium flow rate of 0.5 L/min was achieved with short pulse excitation. A digital holography method is proposed to estimate a basic plasma parameter, i.e., its electron concentration. An automated digital holographic interferometry set-up for the observation and study of a nonthermal plasma jet in a pulse mode is developed and described. The synchronization features of recording devices with the generation of plasma pulses are considered. The electron concentration of the plasma jet is also estimated. The disadvantages of the proposed technique and its further application are discussed.

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19

Ahmed, N., S. Omar, NF Zulkipli, Z. Jusoh, HA Rahman, B. Musa, and SW Harun. "The generation of nanosecond pulses at C-band region with titanium dioxide as a saturable absorber." Journal of Physics: Conference Series 2075, no. 1 (October 1, 2021): 012013. http://dx.doi.org/10.1088/1742-6596/2075/1/012013.

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Abstract A passive mode-locked in an erbium-doped fiber laser with titanium dioxide (TiO2) film as a saturable absorber (SA) has been successfully demonstrated. The film is fabricated using a liquid phase exfoliation, which offers a simple and low-cost method. The self-starting mode-locked was created by inserting a 200-meter-long single-mode fiber into the laser cavity to balance the nonlinearity and dispersion of the cavity. The pulses operate stably at a central wavelength of 1560 nm. The pulse repetition rate was almost fixed at 988 kHz at a tuneable pump power from 145.83 mW to 187.04 mW. The repetition rate shows excellent stability with a signal-to-noise ratio (SNR) of 69 dB whilst the pulse width was virtually constant at 230 ns. The maximum output power was measured at 2.17 mW, eliciting maximum pulse energy of 2.19 nJ. This experiment demonstrates that stable mode-locked pulsed can be generated using TiO2-SA.

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20

Li, Zheng, Zhiwei Shi, and Hai Du. "Analytical Model: Characteristics of Nanosecond Pulsed Plasma Synthetic Jet Actuator in Multiple-Pulsed Mode." Advances in Applied Mathematics and Mechanics 9, no. 2 (January 9, 2017): 439–62. http://dx.doi.org/10.4208/aamm.2015.m1297.

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AbstractMulti-field coupling simulation method based on the physical principles is used to simulate the discharge characteristics of nanosecond pulsed plasma synthetic jet actuator. Considering the effect of the energy transferring for air, the flow characteristics of nanosecond pulsed plasma synthetic jet actuator are simulated. The elastic heating sources and ion joule heating sources are the two main sources of energy. Through the collisions, the energy of ions is transferred to the neutral gas quickly. The flow characteristics of a series of blast waves and the synthetic jet which erupt from the plasma synthetic jet (PSJ) actuator are simulated. The blast wave not only promotes outward, but also accelerates the gas mixing the inhaled gas from the outside cavity with the residual gas inside the cavity. The performances of PSJ actuator fluctuate in the first three incentive cycles and become stable after that.

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21

Афанасьєва, Ольга Валентинівна, Наталія Олексіївна Лалазарова та Олена Георгіївна Попова. "Нові технології лазерної поверхневої обробки". Aerospace technic and technology, № 2 (28 квітня 2021): 59–65. http://dx.doi.org/10.32620/aktt.2021.2.07.

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Subject and purpose. Currently, gas, solid-state, and fiber lasers are used to process materials in the aviation industry. For the thermal treatment of steels, gas CO2 lasers with a capacity of more than 1 kW used, which are reliable in operation but have high cost and low efficiency. There are no results on the use of low-power (up to 20 W) pulsed-mode lasers for surface hardening of steel products. The purpose of this work is to determine the modes of surface hardening of products from carbon and alloy steels using low-power solid-state pulsed YAG lasers. Methodology. For laser hardening, a 5 W solid-state YAG laser was used (diode pumping, radiation wavelength λ = 1,064 μm, pulse mode). The use of a nonlinear crystal made it possible to obtain UV radiation with λ = 0,355 μm (third harmonic). The following modes were investigated: processing with single pulses (duration 0,1...0,4 ms) and multi-pulse processing with short (30...70 ms) pulses. The scanning speed was 8...2 mm/s. The energy in the pulse was determined by the photoelectric method. Thermal hardening was performed on the following steels: У12, P6M5. The possibility of UV radiation hardening was evaluated on steel 20, 45, У12, and ШХ15. Findings. The optimum values of pulse duration for maximum hardness in laser hardening of the investigated steels. With multi-pulse treatment of steels, the pulse duration is shorter than with single-pulse treatment, the hardening intensity is higher, and the quality of the processed surface is better. Single-pulse and multi-pulse processing are accompanied by partial melting of the surface of steel products, which does not allow it to be used in cases where a high quality of the surface is required. Laser hardening of steel by ultraviolet radiation is not accompanied by melting. Conclusion. For surface hardening of products, where partial melting of the surface is possible, low-power lasers in pulse mode can be used. Laser hardening by ultraviolet radiation is a promising direction for thermal hardening of steels, which allows maintaining the original quality of the surface layer. Thermal hardening with low-power lasers can be effective for small-sized areas of the processed parts of the fuel equipment of aircraft engines, friction elements, and, especially, the tool is small.

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22

Pudwat, S., P. Rakkwamsuk, and S. Damrongrattana. "Self-Cleaning Properties of TiO₂ Films Deposited by Reactive Magnetron Sputtering Using Smooth D.C. and Pulsed D.C. Source." Advanced Materials Research 55-57 (August 2008): 453–56. http://dx.doi.org/10.4028/www.scientific.net/amr.55-57.453.

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he TiO2 films were prepared by reactive smooth d.c. and pulsed d.c. magnetron sputtering on glass slide substrates. A metallic titanium target was reactively sputtered in a mixture of argon and oxygen. The influence of smooth d.c. and pulsed d.c. discharge power on films thickness, crystallinity, surface morphology, photocatalytic activity (methylene blue degradation) and hydrophilic activity were studied. At pulsed d.c. sputtering, plasma generator has been used to provide the asymmetric pulsed d.c. bias of the target at 100 kHz and pulsed off-time 4016ns. The structures of the films at 100nm and 300nm thick showed nano-grain size structure. The pulsed d.c. mode deposition exhibited a considerably lower surface roughness, but higher grain size compared to the films deposited with the smooth d.c. mode. At film thickness about 300 nm, the XRD peaks indicated that the dominant structure was anatase for which the preferred orientation was in (101) plane. It did not show any definite change of phase between the films deposited in the smooth d.c. mode and the film deposited in the pulse d.c. mode. For the photocatalytic activity, it was clearly seen that the films deposited by smooth d.c. mode showed a higher photocatalytic activity. The hydrophilic activity test, after the films had been irradiated by an ultraviolet light source for 30 min., the smooth d.c. mode films (thickness 300 nm) showed that a water contact angle can be less than 10°. In this study, the TiO2 films of smooth d.c. mode sputtering could be applied for a self-cleaning glass application.

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23

Fei, Chen, Huo Yu-Jing, He Shu-Fang, and Feng Li-Chun. "Diode-Pumped Nanosecond Pulsed Laser with Pulse-Transmission-Mode Q -Switch." Chinese Physics Letters 18, no. 2 (February 2001): 228–29. http://dx.doi.org/10.1088/0256-307x/18/2/325.

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24

Badziak, J., A. Dubicki, and R. Jarocki. "Short single-mode CO2 laser pulse generation by pulsed Q-switching." Optics & Laser Technology 25, no. 2 (April 1993): 133–37. http://dx.doi.org/10.1016/0030-3992(93)90109-s.

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25

van Zee, Roger D., Joseph T. Hodges, and J. Patrick Looney. "Pulsed, single-mode cavity ringdown spectroscopy." Applied Optics 38, no. 18 (June 20, 1999): 3951. http://dx.doi.org/10.1364/ao.38.003951.

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26

Brunel, Marc, Olivier Emile, Mehdi Alouini, Albert Le Floch, and Fabien Bretenaker. "Self-mode-locked pulsed monomode laser." Optics Letters 24, no. 4 (February 15, 1999): 229. http://dx.doi.org/10.1364/ol.24.000229.

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27

Zaitsev, N. I., E. V. Ilyakov, S. V. Kuzikov, I. S. Kulagin, V. K. Lygin, M. A. Moiseev, M. I. Petelin, and A. S. Shevchenko. "Pulsed high-order volume mode gyroklystron." Radiophysics and Quantum Electronics 48, no. 10-11 (October 2005): 737–40. http://dx.doi.org/10.1007/s11141-006-0002-8.

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28

Hung, Tsung Pin, Chao Ming Hsu, Ah Der Lin, and Jao Hwa Kuang. "Residual Stress and Bead Profile Analysis of Pulsed Nd:YAG Laser Lap Welding." Applied Mechanics and Materials 284-287 (January 2013): 915–18. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.915.

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The weld bead temperature distribution and shape during pulsed Nd:YAG laser lap welding are studied. A volumetric heat source model is derived to include the surface flux and the keyhole heat transfer effects in the pulsed laser lap welding process. The proposed pulsed laser heat transfer mode is employed in a simulation with the commercial finite element software Marc. The numerically computed results of the weld pool dimensions are compared with the experimental results. The comparison shows a good agreement between the simulated and measurement results, indicating that the proposed model is feasible. The results reveal that the pulse duration and spot pitch have considerable influence on the temperature field distribution and the residual stress distribution.

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29

Yang, Li Jun, Xiao Liang Cheng, Gen Wang Wang, Qing Ming Xue, Ye Ding, and Yang Wang. "Experimental Evaluation of Cutting Quality of Carbon Fibre Reinforced Polymer with Pulsed Laser." Applied Mechanics and Materials 868 (July 2017): 172–77. http://dx.doi.org/10.4028/www.scientific.net/amm.868.172.

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To investigate the cutting quality of Carbon Fibre Reinforced Polymer (CFRP) with pulsed laser, experiments of high modulus CFRP were carried out using a Nd: YAG pulsed laser with wavelength of 1064nm. Experiments with five factors and five levels were designed to apply the response surface methodologies (RSM). The influence rule of processing parameters consisting scanning speed, pulse frequency, pulse energy, pulse duration and gas pressure on the morphology of machining region including the kerf width, kerf taper and the width of heat affected zone were studied, and the interactions of these input parameters on cutting qualities were also analyzed. Parameters optimization were conducted based on the mathematical model using the optimization software Design Expert. Verification experiments were carried out to prove the adequacy of the optimization results. The infrared laser with pulsed mode was found to be an effective method in processing high modulus CFRP.

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30

Куропаткин, Ю. П., В. И. Нижегородцев, И. Н. Романов, К. В. Савченко, В. Д. Селемир, Е. В. Урлин, В. А. Фомичёв, А. А. Чинин та О. А. Шамро. "Мобильный ускоритель на базе безжелезного импульсного бетатрона для радиографирования динамических объектов". Журнал технической физики 92, № 2 (2022): 297. http://dx.doi.org/10.21883/jtf.2022.02.52021.196-21.

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The paper concerns the mobile accelerator based on the ironless pulsed betaron. The accelerator is aimed to radiograph dynamic objects with a large optical thickness. It has a possibility to obtain up to three γ-pulses in one cycle of the acceleration. The accelerator operation description and results of its testing powering in a single-pulse mode are provided. The estimated boundary energy of an electron beam is equal to 60 MeV at the capacitance value of 1.8 mF of the storage of the betatron electromagnet pulsed power system. The thickness of the lead test object examined with γ-rays is 140 mm at 4 m from the tantalum target. The full width of the output γ-pulse at half maximum is equal to 120 ns. The dimension of the radiation source is 3×6 mm. The application of these accelerators within the radiographic complex will allow increasing the investigation efficiency due to the optimization of the hydrodynamic experiments geometry and the cost reduction.

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31

Laskovnev, A. P., M. I. Markevich, A. N. Malyshko, V. I. Zhuravleva, and A. M. Chaplanov. "Formation of colloidal solutions of silicon nanoparticles in ethyl alcohol with ultra-short laser pulses." Proceedings of the National Academy of Sciences of Belarus, Physical-Technical Series 66, no. 1 (April 2, 2021): 7–11. http://dx.doi.org/10.29235/1561-8358-2021-66-1-7-11.

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The study of surface morphology of a silicon target after laser exposure, the formation and study of nanoparticles, obtained by laser ablation by ultrashort infrared pulses, were conducted. The material was processed using a yttrium aluminum garnet laser (LS-2134D) with a wavelength of 1064 nm, generating in a two-pulse mode (pulses are separated by a time interval of 3 μs, pulse duration is 10 ns, pulse repetition rate is 10 Hz, single pulse energy ~ 0.05 J). Alcohol solutions of silicon nanoparticles were obtained by laser ablation. It is shown that an ensemble of particles of different sizes (from 20 nm to 2.5 μm) is formed, which have no faceting. Using the method of scanning electron microscopy, the features of the morphology of the surface of the crater of polycrystalline silicon, which is in ethyl alcohol during pulsed laser processing in the double pulse mode, have been established. It is shown that the structure of the crater consists of silicon grains separated from each other by grooves; the material evaporates along the grain boundaries, and wide thermal etching grooves are formed. These results can be used to create solar cells.

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32

Wietfeldt, R. D., and D. A. Frail. "Burst Mode VLBI and Pulsar Applications." International Astronomical Union Colloquium 131 (1991): 76–80. http://dx.doi.org/10.1017/s0252921100013087.

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AbstractThe technique of Burst Mode (BM) VLBI is described and its particular application to the observations of pulsars is explored. The wideband pulsed radiation from these objects is exploited to acquire data at two ends of an interferometer baseline in high-speed bursts and only during the pulsar on-times. The result at the VLBI correlator is an improvement in sensitivity by as much as the inverse pulsar duty cycle, and is a consequence of the bandwidth expansion offered by BM and the intrinsic use of gating. As a result, precision astrometrical studies of pulsars will benefit through the greatly increased instantaneous bandwidths achieved by pulsar BM. The problems, implications, and limitations of acquiring and processing pulsar BM data are discussed.

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33

Braun, Edward. "Reducing Radiation Exposure in Lumbar Transforaminal Epidural Steroid Injections with Pulsed Fluoroscopy: A Randomized, Doubleblind, Controlled Clinical Trial." January 2018 1, no. 21;1 (January 15, 2018): 53–60. http://dx.doi.org/10.36076/ppj.2018.1.53.

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Background: Fluoroscopy-guided lumbar transforaminal epidural steroid injections (L-TFESI) result in radiation exposure that carries risks to patients, physicians, and procedural staff. Objective: We aim to evaluate the feasibility of using pulsed fluoroscopy to safely reduce radiation exposure during L-TFESI. Study Design: This is a prospective, double-blind, randomized controlled trial. Setting: This study took place in a single-center, academic, outpatient interventional pain management clinic. Methods: Patients undergoing L-TFESI were randomly assigned to either continuous mode fluoroscopy (high-dose), pulsed fluoroscopy with 8 pulses per second (medium-dose), or pulsed fluoroscopy with one pulse per second (low-dose). Data on radiation doses and other clinical and demographic factors were also collected. Results: In total, 231 cases were analyzed in the high-dose group (n = 81), medium-dose group (n = 72), and low-dose group (n = 78). Mean radiation effective dose (µSv) was 121 in the highdose group, 57.9 in the medium-dose group, and 34.8 in the low-dose group (P < 0.001). The incidence of inadequate image quality in the pulsed groups was 6% (9/150). The body mass index (BMI, mean ± SD) was significantly higher in patients with inadequate image quality (37.3 ± 7.2) than with adequate quality (30.5 ± 7.2, P = 0.005). Limitations: Radiation doses were measured using the meter on C-arm fluoroscopes rather than by direct measurement. Conclusions: The use of pulsed fluoroscopy during L-TFESI resulted in radiation dose reduction of up to 72.1% without causing any significant adverse events. Pulsed fluoroscopy should be considered as an initial fluoroscopic setting for L-TFESI to reduce radiation exposure. Key words: Radiation, epidural, fluoroscopy, injection, exposure, pulse

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34

Tehrani, P. H., L. G. Hector,, R. B. Hetnarski, and M. R. Eslami. "Boundary Element Formulation for Thermal Stresses During Pulsed Laser Heating." Journal of Applied Mechanics 68, no. 3 (December 5, 2000): 480–89. http://dx.doi.org/10.1115/1.1365155.

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Pulsed lasers are used in a variety of materials processing applications that range from heating for metallurgical transformation to scribing vehicle identification numbers on anodized aluminum strips. These lasers are commonly configured to deliver a large quantity of heat energy in very short time intervals and over very small areas due to the manner in which radiant energy is stored within, and then released from, the laser resonator. At the present time, little is known about the effect of pulse duration on thermomechanical distortion during heating without phase change. To explore this issue, a boundary element method was developed to calculate temperature, displacement, and thermal stress fields in a layer that is rigidly bonded to an inert semi-space. The layer absorbs thermal energy from a repetitively pulsed laser in the plane of its free surface. The effects of two pulse durations, which differ by four-orders-of-magnitude, were examined in this work. The temporal profiles of ultrafast pulses of the order of ten picoseconds (such as those emitted by a mode-locked laser), and pulses of the order of tens-of-nanoseconds (such as those emitted by a Q-switched Nd:YAG laser) were mathematically modeled using a rectified sine function. The spatial profile of each pulse was shaped to approximate a Gaussian strip source. The equations of coupled thermoelasticity, wherein the speed of mechanical distortion due to material expansion during heat absorption is finite, but the speed of heat propagation within the layer is infinite, were solved for both pulse durations. The resulting temperature and stress fields were compared with those predicted in the limit of no thermomechanical coupling.

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35

Ahmad, Harith, Nur Atikah Azali, Leonard Bayang, and Norazriena Yusoff. "Generation of mode-locked thulium/holmium-doped fiber laser assisted by bismuthene/side polished fiber as saturable absorber." Laser Physics Letters 19, no. 7 (May 27, 2022): 075103. http://dx.doi.org/10.1088/1612-202x/ac6804.

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Abstract An all-fiber passively mode-locked laser is demonstrated near the 2.0 µm wavelength region utilizing thulium/holmium-doped fiber as the gain medium and bismuthene/side-polished fiber (SPF) as saturable absorber (SA). The effect of bismuthene concentration on the performance of the generated mode-locked lasers has also been investigated. In this work, bismuthene was obtained by the exfoliation of bismuth under the ultrasonication technique. Two different concentrations of bismuthene (10 and 20 mg ml−1) were prepared to coat the SPF and be further used as SA. Based on the experimental results, the SA with 10 mg ml−1 concentration of bismuthene induced the most stable mode-locked pulses with good performance. The 10 mg ml−1 bismuthene/SPF SA produced pulses at the center wavelength of 1932.69 nm with the 3 dB bandwidth of 2.59 nm and a signal-to-noise ratio value of 63 dB. The generated pulsed laser exhibits pulse energy of 421.3 pJ, peak power of 261.4 W, and average output power of 4.613 mW. Overall, this work reveals the potential of bismuthene/SPF as an SA for generating mode-locked laser pulses, which is useful in photonics applications.

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36

Rakhadilov, B. K., D. B. Buitkenov, M. Adilkhanova, Zh B. Sagdoldina, and Sh R. Kurbanbekov. "Influence of pulse plasma treatment on the phase composition and microhardness of detonation coatings based on Ti-Si-C." Bulletin of the Karaganda University. "Physics" Series 102, no. 2 (June 30, 2021): 33–39. http://dx.doi.org/10.31489/2021ph2/33-39.

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The paper considers the study results of the phase composition and microhardness of detonation coatings based on Ti-Si-C after exposure to pulsed plasma treatment. The CCDS2000 detonation complex was used to obtain the coatings. Coatings surface modification was carried out using pulsed plasma exposure (PPE). The detonation coatings were treated with varying the distance H (30 mm mode 1, 40 mm mode 2, 50 mm mode 3) from the plasmatron to the hardened surface. It is shown that the treated coatings are generally characterized by high microhardness compared to the original coating. It was determined that after treatment by pulsed plasma effects an increase in the intensity of all reflexes phase Ti3SiC2 was observed, and the appearance of reflexes (101, 102, 112, 204, 0016) phase Ti3SiC2 was found, which indicates the increase of the content of Ti3SiC2 phase. The change in the fraction of phases indicates a solid-phase transformation during pulsed-plasma activation. High hardness is observed on the coating surface treated according to mode 3 (50 mm) and as it approaches the surface of the substrate modes 2 (40 mm) and 1 (30 mm) the hardness decreases. It is established that the increase in the microhardness of detonation coatings after pulse-plasma treatment is associated with an increase in the content of Ti3SiC2 phases in the coatings, as well as an increase in the defects density in the modified layer.

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37

Haris, Hazlihan, Malathy Batumalay, Sin Jin Tan, Arni Munira Markom, Ahmad Razif Muhammad, Sulaiman Wadi Harun, Megat Muhammad Ikhsan Megat Hasnan, and Ismail Saad. "Mode-Locked YDFL Using Topological Insulator Bismuth Selenide Nanosheets as the Saturable Absorber." Crystals 12, no. 4 (April 1, 2022): 489. http://dx.doi.org/10.3390/cryst12040489.

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Fiber lasers have long remained relevant for various applications worldwide in many industries. This paper presents a mode-locked ytterbium-doped fiber laser (YDFL) using our home-made topological insulator Bi2Se3 nanosheets (TI Bi2Se3) as the saturable absorber. The fabricated TI Bi2Se3 is transported to the end of the fiber ferrule using an optical deposition process, which is a key ingredient for initiating a pulsed fiber laser. With a pump power of 211.1 mW, the captured repetition rate and pulse width are 8.3 MHz and 6.2 ns, respectively. The length of the setup configuration is approximately 20 m, which corresponds to an output power measurement of 12.4 mW with a calculated pulse energy of 1.5 nJ. There are no significant Kelly sidebands, but the strong stability of the pulsed laser is defined by a high signal-to-noise ratio (SNR) of around 60.35 dB.

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38

Heinz, P., and A. Seilmeier. "Pulsed diode-pumped additive-pulse mode-locked high-peak-power Nd:YLF laser." Optics Letters 21, no. 1 (January 1, 1996): 54. http://dx.doi.org/10.1364/ol.21.000054.

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39

Yao, Jian-tao, Sheng Wang, Yong Zhou, and Hui Dong. "Effects of the Power Supply Mode and Loading Parameters on the Characteristics of Micro-Arc Oxidation Coatings on Magnesium Alloy." Metals 10, no. 11 (October 30, 2020): 1452. http://dx.doi.org/10.3390/met10111452.

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Micro-arc Oxidation (MAO) is a technology for non-ferrous metal surface treatment through growth ceramic coating in situ. To determine the influence of the power supply mode and the loading parameters on the film forming of magnesium alloy micro-arc oxidation processing, the different power supply modes of pulsed direct current DC, pulsed bipolar current (BC) and the pulsed with a discharge loop current (DLC) was used with MAO technology on the AZ91D magnesium alloy. The power load parameters were optimized. The average energy consumption was calculated. Results showed that the role of the negative voltage in the bipolar pulse power supply is to restrain the large arc tendency. Under the pulse power supply with a discharge loop, the current and energy consumption decreases with the increase of the discharge resistance at the same pulse parameters. The big arc phenomenon can be effectively avoided and the impact of load capacitance could be effectively avoided by using the pulse power supply with a discharge loop. Moreover, the processing of the micro-arc oxidation is stable, the arc point is uniform, the surface of the film is smooth, the hole is uniform and the coating is dense, and the film efficiency is improved effectively.

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40

Heo, Seung Yun, Kyeongha Kwon, Michelle Chan, Philipp Gutruf, Alex Burton, Tony Banks, Chongwen Duan, et al. "Wireless, Accumulation Mode Dosimeters for Monitoring Pulsed and Non-Pulsed Germicidal Lamps." IEEE Sensors Journal 21, no. 17 (September 1, 2021): 18706–14. http://dx.doi.org/10.1109/jsen.2021.3091876.

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41

Haruta, H., T. Morii, H. Yoshimura, T. Okada, Y. Ogawa, and T. Okada. "1P323 Molecular mapping using Pulsed-Force-Mode AFM in solution." Seibutsu Butsuri 45, supplement (2005): S112. http://dx.doi.org/10.2142/biophys.45.s112_3.

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42

ELEZ-MARTÍNEZ, PEDRO, JOAN ESCOLÀ-HERNÁNDEZ, ROBERT C. SOLIVA-FORTUNY, and OLGA MARTÍN-BELLOSO. "Inactivation of Saccharomyces cerevisiae Suspended in Orange Juice Using High-Intensity Pulsed Electric Fields." Journal of Food Protection 67, no. 11 (November 1, 2004): 2596–602. http://dx.doi.org/10.4315/0362-028x-67.11.2596.

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Saccharomyces cerevisiae is often associated with the spoilage of fruit juices. The purpose of this study was to evaluate the effect of high-intensity pulsed electric field (HIPEF) treatment on the survival of S. cerevisiae suspended in orange juice. Commercial heat-sterilized orange juice was inoculated with S. cerevisiae (CECT 1319) (108 CFU/ml) and then treated by HIPEFs. The effects of HIPEF parameters (electric field strength, treatment time, pulse polarity, frequency, and pulse width) were evaluated and compared to those of heat pasteurization (90°C/min). In all of the HIPEF experiments, the temperature was kept below 39°C. S. cerevisiae cell damage induced by HIPEF treatment was observed by electron microscopy. HIPEF treatment was effective for the inactivation of S. cerevisiae in orange juice at pasteurization levels. A maximum inactivation of a 5.1-log (CFU per milliliter) reduction was achieved after exposure of S. cerevisiae to HIPEFs for 1,000 μs (4-μs pulse width) at 35 kV/cm and 200 Hz in bipolar mode. Inactivation increased as both the field strength and treatment time increased. For the same electric field strength and treatment time, inactivation decreased when the frequency and pulse width were increased. Electric pulses applied in the bipolar mode were more effective than those in the monopolar mode for destroying S. cerevisiae. HIPEF processing inactivated S. cerevisiae in orange juice, and the extent of inactivation was similar to that obtained during thermal pasteurization. HIPEF treatments caused membrane damage and had a profound effect on the intra-cellular organization of S. cerevisiae.

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43

SONG, H., U. C. PAEK, and D. Y. KIM. "WALK-OFF LENGTH LIMITED SPECTRAL BROADENING IN SUPERCONTINUUM GENERATION." Journal of Nonlinear Optical Physics & Materials 18, no. 01 (March 2009): 99–110. http://dx.doi.org/10.1142/s0218863509004464.

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Detailed spectrum broadening mechanisms in supercontinuum (SC) generation are studied with an all-fiber pulsed laser source and a highly nonlinear dispersion-shifted fiber (HN-DSF). Mode-locked fiber laser pulses are stretched to four different pulse widths, and SC spectra are measured with different propagation distances with these pulses. By observing the development of spectral width with distance, we have observed that self-phase modulation (SPM) rather than soliton fission is the dominant process at the beginning of SC generation in our case. We have also confirmed that four-wave mixing (FWM) and its walk-off problem associated with different spectral components are the major limiting factors in efficient wide-band SC generation.

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44

Zhai, Peizhuo, Songbai Xue, Jianhao Wang, Weizhong Chen, Tao Chen, and Shilei Ji. "Effects of Arc Length Adjustment on Weld Bead Formation and Droplet Transfer in Pulsed GMAW Based on Datum Current Time." Metals 10, no. 5 (May 20, 2020): 665. http://dx.doi.org/10.3390/met10050665.

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The characteristics of weld bead formation and droplet transfer in pulsed gas metal arc weld (GMAW) with different arc lengths were studied by changing the base current time in this work. The results showed that it was easier to cause short circuits and spatters with a short arc. However, the deviation between the deepest point of penetration and the center of bead will be aggravated with the increase of arc length. In addition, more than 90% “one drop per pulse” (ODPP) transfer mode can be obtained when the pulse parameters were selected properly. However, the short arc trended to rise the proportion of “multiple drops per pulse” (MDPP), and the long arc trended towards increasing the proportion of “one drop per multiple pulses” (ODMP). Additionally, with the growth of the arc in the projected transfer zone, the penetration tended to become shallower because of the increase of arc heat dissipation, the fall of arc energy density, and droplet impact force. Overall, the strategy of choosing suitable arc length of pulsed GMAW was summarized: in order to obtain high-quality bead formation and weld joints, a shorter arc in the projected transfer zone was recommended.

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45

Jin, S., N. J. Fisch, and A. H. Reiman. "Pulsed RF schemes for tearing mode stabilization." Physics of Plasmas 27, no. 6 (June 2020): 062508. http://dx.doi.org/10.1063/5.0007861.

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46

Yi, Ying, Ulrich Buttner, Armando A. A. Carreno, David Conchouso, and Ian G. Foulds. "A pulsed mode electrolytic drug delivery device." Journal of Micromechanics and Microengineering 25, no. 10 (September 14, 2015): 105011. http://dx.doi.org/10.1088/0960-1317/25/10/105011.

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47

Shurayts, Alexander, Denis Maruhin, Hajiahmed Zubailov, and Yury Tomashevskiy. "Energy efficient station for cathodic protection of underground metalic pipelines using pulsed current modes." E3S Web of Conferences 121 (2019): 02010. http://dx.doi.org/10.1051/e3sconf/201912102010.

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The perspectivity of protection against corrosion by pulsed current in terms of improving the energy efficiency of cathodic protection stations (CPS) are shown. The cathode polarization of the steel structure to the required protective potential values is provided by the station-controlled current parameters, as well as the transition from the direct current mode to the pulse mode and vice versa. A combined load model was implemented, including a traditional electric circuit for replacing a pipeline and a model based on fuzzy rules (FR), which connect the value of protective potential with the state of protective coatings of an underground steel structure, as well as the parameters of exposure to a corrosive environment. The control of the CPS modes using the FR system made it possible to optimize the station’s power consumption modes taking into account the variability of external environmental factors affecting the underground pipelines.

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48

B, Siva Kumar. "Effect of pulsed mode Phonophoresis in relieving Inflammation and Pain in Supraspinatus tendinitis." Journal of Medical Science And clinical Research 05, no. 05 (May 12, 2017): 21707–11. http://dx.doi.org/10.18535/jmscr/v5i5.77.

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49

Fadhel, Mahmoud Muhanad, Norazida Ali, Haroon Rashid, Nurfarhana Mohamad Sapiee, Abdulwahhab Essa Hamzah, Mohd Saiful Dzulkefly Zan, Norazreen Abd Aziz, and Norhana Arsad. "A Review on Rhenium Disulfide: Synthesis Approaches, Optical Properties, and Applications in Pulsed Lasers." Nanomaterials 11, no. 9 (September 12, 2021): 2367. http://dx.doi.org/10.3390/nano11092367.

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Rhenium Disulfide (ReS2) has evolved as a novel 2D transition-metal dichalcogenide (TMD) material which has promising applications in optoelectronics and photonics because of its distinctive anisotropic optical properties. Saturable absorption property of ReS2 has been utilized to fabricate saturable absorber (SA) devices to generate short pulses in lasers systems. The results were outstanding, including high-repetition-rate pulses, large modulation depth, multi-wavelength pulses, broadband operation and low saturation intensity. In this review, we emphasize on formulating SAs based on ReS2 to produce pulsed lasers in the visible, near-infrared and mid-infrared wavelength regions with pulse durations down to femtosecond using mode-locking or Q-switching technique. We outline ReS2 synthesis techniques and integration platforms concerning solid-state and fiber-type lasers. We discuss the laser performance based on SAs attributes. Lastly, we draw conclusions and discuss challenges and future directions that will help to advance the domain of ultrafast photonic technology.

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50

Li, Feng, Chao Gao, Bo Rui Zheng, and Yu Shuai Wang. "Study of the Boundary Layer on a Plate Aerodynamically Induced by Multiple DBD Plasma Based on PIV." Applied Mechanics and Materials 421 (September 2013): 163–67. http://dx.doi.org/10.4028/www.scientific.net/amm.421.163.

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The boundary layer aerodynamic flow acceleration with one atmosphere uniform induced by multiple dielectric-barrier-discharge plasma actuation were studied based on PIV. Through double actuators alternating discharge, the multiple dielectric barrier discharge mode have been proposed and tested. The efficiencies of the plasma actuators in Pulsed-pulsed, Steady-steady, Pulsed-steady and Steady-pulsed discharge modes were explored. Based on the above results, the boundary layer flow acceleration performance of multiple plasma actuators has been discussed and the more efficient discharge pattern has been proposed. The results of this study indicate that the airflow acceleration effect of multiple plasma actuators mainly occurs in paraelectric direction and the pulsed-pulsed is the more efficient multiple plasma actuation mode.

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