Numerical Study on the Evolution Mechanism of the Crater under a Millisecond Laser

A two-dimensional numerical model considering recoil pressure and Hertz-Knudsen ablation rate was established on the foundation of the laser remelting model to investigate the influence of laser processing parameters on crater feature and melted zone, and it was verified through experiments. The temperature and flow velocity distribution of the molten pool during the formation of the crater were analyzed. The results showed that the ablation velocity could be considered under a higher laser peak power density or higher pulse width due to the metal evaporation caused by heat accumulation. The depth and diameter of the crater were significantly affected by laser peak power density and laser pulse duration. Simultaneously, the height of the edge bulge decreased with the increase in pulse duration after 1.5 ms, and the growth rate of central depth was more rapid than that of edge bulge height with the increase of laser peak power density. In the texture with the same depth, a larger melted zone could be obtained with a longer laser duration than the higher peak power density.

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Strong correlation between the peak power density in the time domain and the luminosity of long γ-ray bursts

Chinese Astronomy and Astrophysics ◽

10.1016/j.chinastron.2005.10.002 ◽

2005 ◽

Vol 29 (4) ◽

pp. 361-369 ◽

Cited By ~ 1

Author(s):

Zhao-yu Yang ◽

Li-ming Song ◽

Rong-feng Shen ◽

Zhuo Li ◽

Yu-sheng Lu

Keyword(s):

Power Density ◽

Time Domain ◽

Strong Correlation ◽

Peak Power ◽

Peak Power Density ◽

Γ Ray ◽

The Time Domain

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Investigation of Transport Phenomena in Micro Flow Channels for Miniature Fuel Cells

1st International Fuel Cell Science, Engineering and Technology Conference ◽

10.1115/fuelcell2003-1711 ◽

2003 ◽

Cited By ~ 8

Author(s):

S. W. Cha ◽

S. J. Lee ◽

Y. I. Park ◽

F. B. Prinz

Keyword(s):

Fuel Cell ◽

Power Density ◽

Peak Power ◽

Gas Flow ◽

Transport Phenomena ◽

Cell Performance ◽

Peak Power Density ◽

Micro Channels ◽

Model Predictions ◽

The Impact

This paper presents a study on the transport phenomena related to gas flow through fuel cell micro-channels, specifically the impact of dimensional scale on the order of 100 microns and below. Especially critical is the ability to experimentally verify model predictions, and this is made efficiently possible by the use of structural photopolymer (SU-8) to directly fabricate functional fuel cell micro-channels. The design and analysis components of this investigation apply 3-D multi-physics modeling to predict cell performance under micro-channel conditions. Interestingly, the model predicts that very small channels (specifically 100 microns and below) result in a significantly higher peak power density than larger counterparts. SU-8 micro-channels with different feature sizes have been integrated into fuel cell prototypes and tested for comparison against model predictions. The results not only demonstrate that the SU-8 channels with metal current collector show quite appreciable performance, but also provide experimental verification of the merits of channel miniaturization. As predicted, the performance in terms of peak power density increases as the feature size of the channel decreases, even though the pressure drop is higher in the more narrow channels. So it has been observed both theoretically and experimentally that cell performance shows an improving trend with micro-channels, and design optimization for miniature fuel cell provides a powerful method for increasing power density.

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The Influence of Mediator Concentration on the Performance of Microbial Fuel Cell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.1520 ◽

2012 ◽

Vol 512-515 ◽

pp. 1520-1524 ◽

Cited By ~ 1

Author(s):

Yu Zhao ◽

Xiao Bin Wang ◽

Peng Li ◽

Yan Ping Sun

Keyword(s):

Methylene Blue ◽

Fuel Cell ◽

Microbial Fuel Cell ◽

Power Density ◽

Peak Power ◽

Electrochemical Impedance ◽

Peak Power Output ◽

Anode Potential ◽

High Concentration ◽

Peak Power Density

Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), power density and anode potential are used to characterize the mediator microbial fuel cell at different methylene blue (MB) concentrations. At lower MB concentration between 9.98×10-3 mmol/L and 1.66×10-1 mmol/L, the increased power density is enabled by using high mediator concentrations. Higher peak power density of 159.6 mw/m2 is observed compared with the peak power density of 36.0 mw/m2. But MB at too high concentration is disadvantageous to the perform of MFC. At the MB concentration of 2.50×10-1 mmol/L, the peak power output is just 128.4 mw/m2, which is lower than 159.6 mw/m2 at MB concentration of 1.66×10-1 mmol/L.

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Carbon Nanotube Free-Standing Membrane of Pt/SWNTs as Catalyst Layer in Hydrogen Fuel Cells

Australian Journal of Chemistry ◽

10.1071/ch06411 ◽

2007 ◽

Vol 60 (7) ◽

pp. 528 ◽

Cited By ~ 10

Author(s):

Jason M. Tang ◽

Kurt Jensen ◽

Wenzhen Li ◽

Mahesh Waje ◽

Paul Larsen ◽

...

Keyword(s):

Carbon Nanotube ◽

Fuel Cell ◽

Power Density ◽

Peak Power ◽

Proton Exchange Membrane ◽

Catalyst Layer ◽

Proton Exchange ◽

Free Standing ◽

Peak Power Density ◽

Exchange Membrane

A simple and promising fuel-cell architecture is demonstrated using a carbon nanotube free-standing membrane (CNTFSM) made from Pt supported on purified single-walled carbon nanotubes (Pt/SWNT), which act as the catalyst layer in a hydrogen proton exchange membrane fuel cell without the need for Nafion in the catalyst layer. The CNTFSM made from Pt/SWNT at a loading of 0.082 mg Pt cm–2 exhibits higher performance with a peak power density of 0.675 W cm–2 in comparison with a commercially available E-TEK electrocatalyst made of Pt supported on XC-72 carbon black, which had a peak power density of 0.395 W cm–2 at a loading of 0.084 mg Pt cm–2 also without Nafion in the catalyst layer.

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The fast optimal voltage partitioning algorithm for peak power density minimization

2010 IEEE/ACM International Conference on Computer-Aided Design (ICCAD) ◽

10.1109/iccad.2010.5654144 ◽

2010 ◽

Cited By ~ 1

Author(s):

Jia Wang ◽

Shiyan Hu

Keyword(s):

Power Density ◽

Peak Power ◽

Peak Power Density ◽

Partitioning Algorithm

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Application of platinum-cobalt-boron as the anode material for sodium borohydride-hydrogen peroxide fuel cells

Chemija ◽

10.6001/chemija.v29i4.3838 ◽

2018 ◽

Vol 29 (4) ◽

Cited By ~ 1

Author(s):

Aldona Balčiūnaitė ◽

Zita Sukackienė ◽

Loreta Tamašauskaitė-Tamašiūnaitė ◽

Rimantas Vaitkus ◽

Eugenijus Norkus

Keyword(s):

Hydrogen Peroxide ◽

Fuel Cells ◽

Fuel Cell ◽

Power Density ◽

Anode Materials ◽

Peak Power ◽

Anode Catalysts ◽

Fuel Cell Performance ◽

Peak Power Density ◽

Density Values

The electroless deposition and galvanic displacement methods were used for the fabrication of cobalt–boron (CoB) catalysts modified with small amounts of platinum crystallites in the range of 9.8 to 14.4 μgPt cm–2. The prepared catalysts were studied as the anode materials for direct borohydride–hydrogen peroxide (NaBH4/H2O2) fuel cells at temperatures of 25–55°C. Polarization curves have been recorded with the aim to evaluate the fuel cell performance using the prepared CoB and that modified with Pt crystallites as the anode catalysts. For all catalysts (pure CoB and PtCoB) investigated, the peak power density values increase consecutively with the increment in temperature from 25°C up to 55°C. The values from 86–146 mV cm–2 and 146–234 mV cm–2 were determined for pure CoB and PtCoB catalysts, respectively. The highest specific peak power density of 21.5 kWgPt–1 was achieved at 55°C temperature when the PtCoB catalyst with the Pt loading of 9.8 μgPtcm–2 was employed as the anode catalyst in the NaBH4/H2O2 single fuel cell.

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Human auditory system response to modulated electromagnetic energy

Journal of Applied Physiology ◽

10.1152/jappl.1962.17.4.689 ◽

1962 ◽

Vol 17 (4) ◽

pp. 689-692 ◽

Cited By ~ 92

Author(s):

Allan H. Frey

Keyword(s):

Power Density ◽

Peak Power ◽

Acoustic Noise ◽

Average Power ◽

Critical Factor ◽

Electromagnetic Energy ◽

Acoustic Energy ◽

System Response ◽

Peak Power Density ◽

Energy Sensor

The intent of this paper is to bring a new phenomenon to the attention of physiologists. Using extremely low average power densities of electromagnetic energy, the perception of sounds was induced in normal and deaf humans. The effect was induced several hundred feet from the antenna the instant the transmitter was turned on, and is a function of carrier frequency and modulation. Attempts were made to match the sounds induced by electromagnetic energy and acoustic energy. The closest match occurred when the acoustic amplifier was driven by the rf transmitter's modulator. Peak power density is a critical factor and, with acoustic noise of approximately 80 db, a peak power density of approximately 275 mw/ cm2 is needed to induce the perception at carrier frequencies of 425 mc and 1,310 mc. The average power density can be at least as low as 400 μw/cm2. The evidence for the various possible sites of the electromagnetic energy sensor are discussed and locations peripheral to the cochlea are ruled out.

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Plasma membrane temperature gradients and multiple cell permeabilization induced by low peak power density femtosecond lasers

Biochemistry and Biophysics Reports ◽

10.1016/j.bbrep.2015.11.019 ◽

2016 ◽

Vol 5 ◽

pp. 168-174 ◽

Cited By ~ 3

Author(s):

Allen L. Garner ◽

V. Bogdan Neculaes ◽

Maxim Deminsky ◽

Dmitry V. Dylov ◽

Chulmin Joo ◽

...

Keyword(s):

Plasma Membrane ◽

Power Density ◽

Peak Power ◽

Femtosecond Lasers ◽

Temperature Gradients ◽

Cell Permeabilization ◽

Peak Power Density ◽

Multiple Cell

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A high-performance supportless silver nanowire catalyst for anion exchange membrane fuel cells

Journal of Materials Chemistry A ◽

10.1039/c4ta05005c ◽

2015 ◽

Vol 3 (4) ◽

pp. 1410-1416 ◽

Cited By ~ 46

Author(s):

L. Zeng ◽

T. S. Zhao ◽

L. An

Keyword(s):

Fuel Cells ◽

Anion Exchange ◽

Power Density ◽

Peak Power ◽

High Performance ◽

Anion Exchange Membrane ◽

Silver Nanowire ◽

Peak Power Density ◽

Exchange Membrane

The use of supportless Ag NWs enabled the H2/O2 AEMFC to yield a peak power density of 164 mW cm−2.

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A low-loading Ru-rich anode catalyst for high-power anion exchange membrane fuel cells

Chemical Communications ◽

10.1039/d0cc00008f ◽

2020 ◽

Vol 56 (42) ◽

pp. 5669-5672

Author(s):

Zhanna Tatus-Portnoy ◽

Anna Kitayev ◽

Thazhe Veettil Vineesh ◽

Ervin Tal-Gutelmacher ◽

Miles Page ◽

...

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Anion Exchange ◽

Power Density ◽

High Power ◽

Peak Power ◽

Anion Exchange Membrane ◽

Anode Catalyst ◽

Peak Power Density ◽

Exchange Membrane

Herein, we report a Ru-rich anode catalyst for alkaline exchange membrane fuel cells. At 80 °C, a fuel cell with a RuPdIr/C anode and Ag based cathode attained a peak power density close to 1 W cm−2 with 0.2 mg cm−2 anode loading in comparison to 0.77 W cm−2 for the cell tested with the same metal loading of Pt.

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