Visualization of flow structure around a hypersonic re-entry capsule using the electrical discharge method

2004 ◽  
Vol 7 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Masatomi Nishio ◽  
Shinji Sezaki ◽  
Hiroaki Nakamura
Keyword(s):  
Flow Structure ◽  
Electrical Discharge ◽  
Discharge Method

scholarly journals Antibacterial Activity of The Iron-Zinc Oxide Nanoparticles Synthesized Via Electric Discharge Method

2021 ◽  
Author(s):  
Fereshteh Shahbazi ◽  
Reza Ahmadi ◽  
Mohammad Noghani ◽  
Gholamreza Karimi
Keyword(s):  
Zinc Oxide ◽  
Electrical Discharge ◽  
Zinc Oxide Nanoparticles ◽  
Viral Infections ◽  
Antibacterial Properties ◽  
Oxide Nanoparticles ◽  
Gram Negative Bacteria ◽  
Discharge Method ◽  
Electric Discharge Method ◽  
Novel Antibiotics

Abstract With the increase in diseases caused by bacterial and viral infections, the need for antibiotics has increased. On the other hand, by creating drug resistance to organicmoietiesbased antibiotics, novel antibiotics have attracted the attention of researchers.Nano-scale metal oxides are increasingly being considered for medical applications, especially as antibacterial agents.In this study, iron oxide nanoparticles (IONPs) and zinc oxide nanoparticles (ZONPs) were prepared via electrical discharge method in liquid medium by changing parameters such as wire diameter and electric current intensity. Synthesized NPs were evaluated by XRD, UV_Visible, FE_SEM, EDS, HR_TEM and TEM analyzes. Also, the antibacterial properties of these nanoparticles were evaluated in different ways against gram-positive and gram-negative bacteria.

Theoretical and Experimental Research on Preparing Silicon Microspheres by Pulsed Electrical Discharge Method

2013 ◽  
Vol 456 ◽  
pp. 503-506
Author(s):  
Juan Hong ◽  
Wei Zhang
Keyword(s):  
Electrical Discharge ◽  
Cost Effective ◽  
Local Area ◽  
Field Analysis ◽  
Selective Emitter ◽  
New Type ◽  
Pulsed Electrical Discharge ◽  
Sphere Formation ◽  
Discharge Method ◽  
Micro Topography

In this paper, a new method of preparing silicon microspheres is introduced. Silicon microspheres have been produced under transient and high temperature generated with pulsed electrical discharge in the liquid. Their micro topography and composition are characterized and analyzed by SEM/EDS. The mechanism of sphere formation is studied by local area temperature field analysis using ANSYS. Various sizes of silicon particles (0.5-30μm) are successfully prepared under the different processing conditions. It is demonstrated that pulsed electrical discharge method is energy controllable, cost-effective, and is of great significance to the preparation of silicon ink which is the important material of new type of TFSC and selective emitter cell.

How to increase the efficiency of the electrical discharge method for destruction of nonconductive solid materials

2016 ◽  
Vol 79 (14) ◽  
pp. 1632-1636 ◽  
Author(s):  
N. V. Voitenko ◽  
A. S. Yudin ◽  
N. S. Kuznetsova ◽  
E. G. Krastelev
Keyword(s):  
Electrical Discharge ◽  
Solid Materials ◽  
Discharge Method

scholarly journals Novel electrical discharge machining system with real-time control and monitoring for preparing nanoiron colloid

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879170 ◽  
Author(s):  
Kuo-Hsiung Tseng ◽  
Chaur-Yang Chang ◽  
Mei-Jiun Chen ◽  
Yi-Kai Tseng
Keyword(s):  
Real Time ◽  
Electrical Discharge ◽  
Closed Loop ◽  
Electrical Discharge Machining ◽  
Proportional Integral Derivative ◽  
Proportional Integral Derivative Controller ◽  
Interelectrode Gap ◽  
Machining System ◽  
Arduino Microcontroller ◽  
Discharge Method

Nanoiron colloid is remarkably suitable for medical, engineering, and other applications because it exhibits excellent properties such as nontoxicity, biocompatibility, and high chemical stability. Because no studies have examined preparation of nanoiron colloid through electric spark discharge method, an electrical discharge machining system for preparing nanoiron colloid was developed in this study based on automated electric spark discharge method with real-time monitoring. An Arduino microcontroller, laser positioning technology, and closed-loop motor control were combined for automatic alignment of the two discharge electrodes. This electrode alignment method enabled achieving electrode alignment accuracy of 0.139 mm. The real-time monitoring applied the Ziegler–Nichols method with a proportional–integral–derivative controller for closed-loop control of the interelectrode gap that, compared with the manually tuned proportional–integral–derivative controller, increased the interelectrode gap discharge success rate from 22.25 to 28.99. A user-friendly interface and process parameters were realized through VisSim software, an Arduino microcontroller, and an RT/DAC4 PCI card. This design enabled obtaining data on process efficiency and providing real-time process diagnosis. Compared with colloids prepared using chemical methods, the nanoiron colloids prepared in this study contained only iron and oxygen; therefore, they would be safer for application in the human body. According to the UV-Vis and Zetasizer analyses, the absorbance peak of the nanoiron colloid prepared with this system ranged from 200 to 220 nm, and the zeta potential was approximately –11.6 mV with a diameter of approximately 155.9 nm. These results verified that this electrical discharge machining system can prepare nanoiron colloid featuring excellent suspension stability.

scholarly journals Deriving Optimized PID Parameters of Nano-Ag Colloid Prepared by Electrical Spark Discharge Method

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1091
Author(s):  
Kuo-Hsiung Tseng ◽  
Yur-Shan Lin ◽  
Yun-Chung Lin ◽  
Der-Chi Tien ◽  
Leszek Stobinski
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Electrical Discharge ◽  
Short Circuit ◽  
Spark Discharge ◽  
Chemical Pollution ◽  
Ag Colloid ◽  
Short Circuits ◽  
Discharge Method ◽  
Electrical Spark Discharge Method

Using the electrical spark discharge method, this study prepared a nano-Ag colloid using self-developed, microelectrical discharge machining equipment. Requiring no additional surfactant, the approach in question can be used at the ambient temperature and pressure. Moreover, this novel physical method of preparation produced no chemical pollution. This study conducted an in-depth investigation to establish the following electrical discharge conditions: gap electrical discharge, short circuits, and open circuits. Short circuits affect system lifespan and cause electrode consumption, resulting in large, non-nanoscale particles. Accordingly, in this study, research for and design of a new logic judgment circuit set was used to determine the short-circuit rate. The Ziegler–Nichols proportional–integral–derivative (PID) method was then adopted to find optimal PID values for reducing the ratio between short-circuit and discharge rates of the system. The particle size, zeta potential, and ultraviolet spectrum of the nano-Ag colloid prepared using the aforementioned method were also analyzed with nanoanalysis equipment. Lastly, the characteristics of nanosized particles were analyzed with a transmission electron microscope. This study found that the lowest ratio between short-circuit rates was obtained (1.77%) when PID parameters were such that Kp was 0.96, Ki was 5.760576, and Kd was 0.039996. For the nano-Ag colloid prepared using the aforementioned PID parameters, the particle size was 3.409 nm, zeta potential was approximately −46.8 mV, absorbance was approximately 0.26, and surface plasmon resonance was 390 nm. Therefore, this study demonstrated that reducing the short-circuit rate can substantially enhance the effectiveness of the preparation and produce an optimal nano-Ag colloid.

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