On Reducing Peak Current and Power during Test

Electrical Discharge Machining (EDM) is extensively used to manufacture different conductive materials, including difficult to machine materials with intricate profiles. Powder Mixed Electro-Discharge Machining (PMEDM) is a modern innovation in promoting the capabilities of conventional EDM. In this process, suitable materials in fine powder form are mixed in the dielectric fluid. An equal percentage of graphite and silicon carbide powders have been mixed together with the transformer oil and used as the dielectric media in this work. The aim of this study is to investigate the effect of some process parameters such as peak current, pulse-on time, and powder concentration of machining High-speed steel (HSS)/(M2) on the material removal rate (MRR), tool wear rate (TWR) and the surface roughness (Ra). Experiments have been designed and analyzed using Response Surface Methodology (RSM) approach by adopting a face-centered central composite design (FCCD). It is found that added graphite-silicon carbide mixing powder to the dielectric fluid enhanced the MRR and Ra as well as reduced the TWR at various conditions. Maximum MRR was (0.492 g/min) obtained at a peak current of (24 A), pulse on (100 µs), and powder concentration (10 g/l), minimum TWR was (0.00126 g/min) at (10 A, 100 µs, and 10 g/l), and better Ra was (3.51 µm) at (10 A, 50 µs, and 10 g/l).

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Indirect Determination of Amikacin by Gold Nanoparticles as Redox Probe

Current Drug Delivery ◽

10.2174/1567201817666200719005919 ◽

2020 ◽

Vol 17 ◽

Author(s):

Mansureh Alizadeh ◽

Mandana Amiri ◽

Abolfazl Bezaatpour

Keyword(s):

Gold Nanoparticles ◽

Bacterial Infections ◽

Limit Of Detection ◽

Pharmaceutical Preparation ◽

Cathodic Peak ◽

Easy Method ◽

Peak Current ◽

Indirect Determination ◽

Tract Infections

: Amikacin is an aminoglycoside antibiotic used for many gram-negative bacterial infections like infections in the urinary tract, infections in brain, lungs and abdomen. Electrochemical determination of amikacin is a challenge in electroanalysis because it shows no voltammetric peak at the surface of bare electrodes. In this approach, a very simple and easy method for indirect voltammetric determination of amikacin presented in real samples. Gold nanoparticles were electrodeposited at the surface of glassy carbon electrode in constant potential. The effect of several parameters such as time and potential of deposition, pH and scan rates on signal were studied. The cathodic peak current of Au3+ decreased with increasing amikacin concentration. Quantitative analysis of amikacin was performed using differential pulse voltammetry by following cathodic peak current of gold ions. Two dynamic linear ranges of 1.0 × 10−8–1.0 × 10-7 M and 5.0 × 10−7–1.0 × 10-3 M were obtained and limit of detection was estimated 3.0× 10−9 M. The method was successfully determined amikacin in pharmaceutical preparation and human serum. The effect of several interference in determination of amikacin was also studied.

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A peak current and power pad count reduction tool for system-level IC designers

2009 IEEE 13th International Symposium on Consumer Electronics ◽

10.1109/isce.2009.5156905 ◽

2009 ◽

Author(s):

Tsung-Yi Wu ◽

Tzi-Wei Kao ◽

Shi-Yi Huang ◽

Tai-Lun Li ◽

How-Rern Lin

Keyword(s):

System Level ◽

Peak Current

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Design of a Universal Charger for a Light Electric Vehicle with Effect of an RCD Snubber on Peak Current Control

2020 International Conference on Electrical Engineering and Control Technologies (CEECT) ◽

10.1109/ceect50755.2020.9298611 ◽

2020 ◽

Author(s):

Richard Beyer ◽

Peter Freere ◽

Theo van Niekerk ◽

Ertugul Sonmez

Keyword(s):

Electric Vehicle ◽

Current Control ◽

Peak Current

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Characteristics of Microstructure Evolution during FAST Joining of the Tungsten Foil Laminate

Metals ◽

10.3390/met11060886 ◽

2021 ◽

Vol 11 (6) ◽

pp. 886

Author(s):

Xiaoyue Tan ◽

Wujie Wang ◽

Xiang Chen ◽

Yiran Mao ◽

Andrey Litnovsky ◽

...

Keyword(s):

Critical Current ◽

Current Density ◽

High Current Density ◽

Operation Mode ◽

Sharp Peak ◽

Advanced Materials ◽

Peak Current ◽

Tungsten Foil ◽

Field Assisted Sintering ◽

Joining Process

The tungsten (W) foil laminate is an advanced material concept developed as a solution for the low temperature brittleness of W. However, the deformed W foils inevitably undergo microstructure deterioration (crystallization) during the joining process at a high temperature. In this work, joining of the W foil laminate was carried out in a field-assisted sintering technology (FAST) apparatus. The joining temperature was optimized by varying the temperature from 600 to 1400 °C. The critical current for mitigating the microstructure deterioration of the deformed W foil was evaluated by changing the sample size. It is found that the optimal joining temperature is 1200 °C and the critical current density is below 418 A/cm2. According to an optimized FAST joining process, the W foil laminate with a low microstructure deterioration and good interfacial bonding can be obtained. After analyzing these current profiles, it was evident that the high current density (sharp peak current) is the reason for the significant microstructure deterioration. An effective approach of using an artificial operation mode was proposed to avoid the sharp peak current. This study provides the fundamental knowledge of FAST principal parameters for producing advanced materials.

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