Radiative Properties of Micro/Nanoscale Particles in Dispersions for Photothermal Energy Conversion

2012 ◽  
pp. 143-174 ◽  
Author(s):  
Qunzhi Zhu ◽  
Zhuomin Zhang
Keyword(s):  
Energy Conversion ◽  
Radiative Properties ◽  
Nanoscale Particles

scholarly journals Hotplate precipitation gauge calibrations and field measurements

2018 ◽  
Vol 11 (1) ◽  
pp. 441-458 ◽  
Author(s):  
Nicholas Zelasko ◽  
Adam Wettlaufer ◽  
Bujidmaa Borkhuu ◽  
Matthew Burkhart ◽  
Leah S. Campbell ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Surface Area ◽  
Conversion Factor ◽  
Field Measurements ◽  
Radiative Properties ◽  
Shortwave Radiation ◽  
Actual Surface ◽  
Precipitation Gauge ◽  
Radiation Sensors ◽  
S Application

Abstract. First introduced in 2003, approximately 70 Yankee Environmental Systems (YES) hotplate precipitation gauges have been purchased by researchers and operational meteorologists. A version of the YES hotplate is described in Rasmussen et al. (2011; R11). Presented here is testing of a newer version of the hotplate; this device is equipped with longwave and shortwave radiation sensors. Hotplate surface temperature, coefficients describing natural and forced convective sensible energy transfer, and radiative properties (longwave emissivity and shortwave reflectance) are reported for two of the new-version YES hotplates. These parameters are applied in a new algorithm and are used to derive liquid-equivalent accumulations (snowfall and rainfall), and these accumulations are compared to values derived by the internal algorithm used in the YES hotplates (hotplate-derived accumulations). In contrast with R11, the new algorithm accounts for radiative terms in a hotplate's energy budget, applies an energy conversion factor which does not differ from a theoretical energy conversion factor, and applies a surface area that is correct for the YES hotplate. Radiative effects are shown to be relatively unimportant for the precipitation events analyzed. In addition, this work documents a 10 % difference between the hotplate-derived and new-algorithm-derived accumulations. This difference seems consistent with R11's application of a hotplate surface area that deviates from the actual surface area of the YES hotplate and with R11's recommendation for an energy conversion factor that differs from that calculated using thermodynamic theory.

scholarly journals Fractal-Like Materials Design with Optimized Radiative Properties for High-Efficiency Solar Energy Conversion

2016 ◽  
Author(s):  
Clifford K. Ho ◽  
Jesus D. Ortega ◽  
Joshua Mark Christian ◽  
Julius E. Yellowhair ◽  
Daniel A. Ray ◽  
...  
Keyword(s):  
Solar Energy ◽  
Energy Conversion ◽  
High Efficiency ◽  
Solar Energy Conversion ◽  
Materials Design ◽  
Radiative Properties

scholarly journals Hotplate Precipitation Gauge Calibrations and Field Measurements

2017 ◽  
Author(s):  
Nicholas Zelasko ◽  
Adam Wettlaufer ◽  
Bujidmaa Borkhuu ◽  
Matthew Burkhart ◽  
Leah S. Campbell ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Surface Area ◽  
Conversion Factor ◽  
Field Measurements ◽  
Radiative Properties ◽  
Shortwave Radiation ◽  
Actual Surface ◽  
Precipitation Gauge ◽  
Radiation Sensors ◽  
S Application

Abstract. First introduced in 2003, approximately 70 Yankee Environmental Systems (YES) hotplate precipitation gauges have been purchased by researchers and operational meteorologists. A version of the YES hotplate is described in Rasmussen et al. (2011; R11). Presented here is indoor- and field-based testing of a newer version of the hotplate; this device is equipped with longwave and shortwave radiation sensors. Hotplate surface temperature, coefficients describing natural and forced convective sensible energy transfer, and radiative properties (longwave emissivity and shortwave reflectance) are reported for two of the new-version YES hotplates. These parameters are applied in a new algorithm and used to derive liquid-equivalent accumulations for snowfall and rainfall. These accumulations are compared to values derived by the internal algorithm used in the YES hotplates (hotplate-derived accumulations) and to weighing gauge accumulations. In contrast with R11, the new algorithm accounts for radiative terms in a hotplate’s energy budget, applies an energy conversion factor which does not differ from a theoretical energy conversion factor, and applies a surface area that is correct for the YES hotplate. Radiative effects are shown to be relatively unimportant for the precipitation events analyzed. In addition, this work documents a 10 % difference between the hotplate-derived and new-algorithm-derived accumulations. This difference seems consistent with R11’s application of a hotplate surface area that deviates from the actual surface area of the YES hotplate and with R11’s recommendation for an energy conversion factor that differs from that calculated using thermodynamic theory.

Artificial cells containing sustainable energy conversion engines

2019 ◽  
Vol 3 (5) ◽  
pp. 573-578 ◽  
Author(s):  
Kwanwoo Shin
Keyword(s):  
Energy Conversion ◽  
Nicotinamide Adenine Dinucleotide ◽  
Sustainable Energy ◽  
Living Cells ◽  
Energy Transduction ◽  
Artificial Cells ◽  
Energy Conversion Process ◽  
Metabolic Reactions ◽  
Metabolic Activities ◽  
Reduced Nicotinamide Adenine Dinucleotide

Living cells naturally maintain a variety of metabolic reactions via energy conversion mechanisms that are coupled to proton transfer across cell membranes, thereby producing energy-rich compounds. Until now, researchers have been unable to maintain continuous biochemical reactions in artificially engineered cells, mainly due to the lack of mechanisms that generate energy-rich resources, such as adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide (NADH). If these metabolic activities in artificial cells are to be sustained, reliable energy transduction strategies must be realized. In this perspective, this article discusses the development of an artificially engineered cell containing a sustainable energy conversion process.

Characterizing the convective heat exchange with plastic shading nets under natural arid conditions

2019 ◽  
pp. 11-20
Author(s):  
Ahmed M Abdel-Ghanya ◽  
Ibrahim M Al-Helal
Keyword(s):  
Wind Speed ◽  
Thermal Radiation ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Convective Heat Exchange ◽  
Radiative Properties ◽  
Wooden Frame ◽  
Arid Conditions ◽  
Air Temperatures ◽  
Radiation Fluxes

Plastic nets are extensively used for shading purposes in arid regions such as in the Arabian Peninsula. Quantifying the convection exchange with shading net and understanding the mechanisms (free, mixed and forced) of convection are essential for analyzing energy exchange with shading nets. Unlike solar and thermal radiation, the convective energy, convective heat transfer coefficient and the nature of convection have never been theoretically estimated or experimentally measured for plastic nets under arid conditions. In this study, the convected heat exchanges with different plastic nets were quantified based on an energy balance applied to the nets under outdoor natural conditions. Therefore, each net was tacked onto a wooden frame, fixed horizontally at 1.5-m height over the floor. The downward and upward solar and thermal radiation fluxes were measured below and above each net on sunny days; also the wind speed over the net, and the net and air temperatures were measured, simultaneously. Nets with different porosities, colors and texture structures were used for the study. The short and long wave’s radiative properties of the nets were pre-determined in previous studies to be used. Re and Gr numbers were determined and used to characterize the convection mechanism over each net. The results showed that forced and mixed convection are the dominant modes existing over the nets during most of the day and night times. The nature of convection over nets depends mainly on the wind speed, net-air temperature difference and texture shape of the net rather than its color and its porosity.

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