Removal of tetracycline from livestock wastewater by positive single pulse current electrocoagulation: Mechanism, toxicity assessment and cost evaluation

2009 ◽

Vol 19 (01) ◽

pp. 173-181

Author(s):

HEATHER O'BRIEN ◽

M. GAIL KOEBKE

Keyword(s):

Silicon Carbide ◽

Recovery Time ◽

Pulse Current ◽

Pulse Discharge ◽

Single Pulse ◽

Electronic Components ◽

Army Research Laboratory ◽

Pulse Switching ◽

Reliable Performance ◽

High Pulse

The U. S. Army Research Laboratory (ARL) is investigating compact, energy-dense electronic components to realize high-power, vehicle-mounted survivability and lethality systems. These applications require switching components that are low in weight and volume, exhibit reliable performance, and are easy to integrate into the vehicles' systems. The devices reported here are 4 mm × 4 mm silicon carbide GTOs rated for 3000 V blocking. These devices were packaged at ARL for high pulse current capability, high voltage protection, and minimum package inductance. The GTOs were switched in a 1-ms half-sine, single-pulse discharge circuit to determine reliable peak current and recovery time (or Tq). The GTOs were repeatedly switched over 300 A peak (3.3 A/cm2 and an action of 60 A2s) with a recovery time of 20 µs. The switches were also evaluated for dV/dt immunity up to an instantaneous slope of 3 kV/ µs.

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Hardness and Wear Resistance of Ni/Al2O3 Composite Coatings by Electrodeposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.654 ◽

2010 ◽

Vol 154-155 ◽

pp. 654-657 ◽

Cited By ~ 1

Author(s):

Li Min Chang ◽

Jian Hua Liu ◽

Rui Jun Zhang

Keyword(s):

Wear Resistance ◽

Cross Section ◽

Pulse Current ◽

Composite Coatings ◽

Single Pulse ◽

Al2o3 Content ◽

Measuring Device ◽

Al2o3 Composite ◽

Fine Microstructure ◽

Stress Measuring

Ni/Al2O3 composite coatings were prepared by direct current (DC), single pulse current (PC) and pulse reversal current (PRC), respectively. The hardness and wear resistance of the coatings were investigated and the morphology and elements distribution in cross-section were analyzed by the application of SEM/EDS, XRF and XRD equipped with stress measuring device. The results show that the hardness of the three kinds of coatings increase with increasing Al2O3 content. The coating prepared by PRC plating exhibits higher hardness and better wear resistance, while that of DC plating has lower hardness and poorer wear resistance. The higher hardness and better wear resistance of coating of PRC plating can be ascribed to fine microstructure and weaker stress between substrate and coatings.

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Cd removal by direct and positive single pulse current electrocoagulation: Operating conditions and energy consumption

Environmental Technology & Innovation ◽

10.1016/j.eti.2020.101123 ◽

2020 ◽

Vol 20 ◽

pp. 101123

Author(s):

Jialin Yang ◽

Fangyuan Liu ◽

Ya Bu ◽

Nan Wei ◽

Songlin Liu ◽

...

Keyword(s):

Energy Consumption ◽

Pulse Current ◽

Single Pulse ◽

Operating Conditions ◽

Cd Removal

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Experimental results of testing high-temperature-high-current pulsed operation of SiC MOSETs and SiC diodes

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/hitec-tp13 ◽

2014 ◽

Vol 2014 (HITEC) ◽

pp. 000066-000071

Author(s):

Steven A. Morris ◽

Ruichen Zhao ◽

Zinovy Krugliak

Keyword(s):

Pulse Current ◽

Schottky Diodes ◽

Single Pulse ◽

Maximum Temperature ◽

Resonant Circuit ◽

High Current ◽

Hot Plate ◽

Peak Current ◽

Conduction Loss ◽

Pulse Switching

Using hot plate experiments testing to a maximum temperature of 200 °C, we performed tests to determine the maximum single pulse current allowable for Cree CMF20120D SiC MOSFETs and Cree C4D40120D Schottky diodes. Using single pulse switching of a resonant circuit, a half-sine shaped current pulse of 5∼10 μsec duration was used to test the devices. A criterion for maximum allowable peak current was determined from the point of dramatic increase in conduction loss as a function of peak current. At 200 °C, maximum single pulse current was found to be 200 amp for the SiC MOSFET and about 500 amp for the SiC Schottky diode (both legs in parallel). We also report measurements of leakage current on the devices as a function of temperature, and will present measurements on an IGBT device of comparable current rating for comparison. Simple measurements of this type are a useful way of determining operational limits of SiC devices at temperatures that are not reported in the device data sheet.

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Ultrafast Growth of Large Area Graphene on Si Wafer by a Single Pulse Current

Molecules ◽

10.3390/molecules26164940 ◽

2021 ◽

Vol 26 (16) ◽

pp. 4940

Author(s):

Yifei Ge ◽

Mingming Lu ◽

Jiahao Wang ◽

Jianxun Xu ◽

Yuliang Zhao

Keyword(s):

High Efficiency ◽

Pulse Current ◽

Scale Up ◽

Graphene Film ◽

Single Pulse ◽

Dimensional Structure ◽

Wafer Surface ◽

Nickel Layer ◽

Large Area ◽

Si Wafer

Graphene has many excellent optical, electrical and mechanical properties due to its unique two-dimensional structure. High-efficiency preparation of large area graphene film is the key to achieve its industrial applications. In this paper, an ultrafast quenching method was firstly carried out to flow a single pulse current through the surface of a Si wafer with a size of 10 mm × 10 mm for growing fully covered graphene film. The wafer surface was firstly coated with a 5-nm-thick carbon layer and then a 25-nm-thick nickel layer by magnetron sputtering. The optimum quenching conditions are a pulse current of 10 A and a pulse width of 2 s. The thus-prepared few-layered graphene film was proved to cover the substrate fully, showing a high conductivity. Our method is simple and highly efficient and does not need any high-power equipment. It is not limited by the size of the heating facility due to its self-heating feature, providing the potential to scale up the size of the substrates easily. Furthermore, this method can be applied to a variety of dielectric substrates, such as glass and quartz.

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