scholarly journals Experimental Study on Absorption Behavior and Efficiency of Brine in Hazardous Gas Absorption Treatment

2022 ◽  
Vol 6 (1) ◽  
pp. 4
Author(s):  
Ga-young Jung ◽  
Seul-gi Lee ◽  
Jun-seo Lee ◽  
Byung-chol Ma
Keyword(s):  
High Efficiency ◽  
Bubble Column ◽  
Low Cost ◽  
Water Soluble ◽  
Gas Absorption ◽  
Bubble Columns ◽  
Experimental Results ◽  
Design Data ◽  
Hazardous Gases ◽  
Absorption Performance

There have been studies recently on bubble-column scrubbers with low cost and high efficiency for the absorption and treatment of hazardous gases in the event of a chemical spill. Bubble columns are vulnerable to freezing at temperatures below zero because the absorbents generally do not circulate. To address this issue, this study focused on the applicability, absorbed amount, and performance of brine as an absorbent. Under three different temperatures, i.e., −5 °C, −8 °C and −10 °C we examined brine (NaCl, CaCl2, and MgCl2) by varying the concentration required at each temperature. Following the experiments, CaCl2 brine was determined as the optimal brine for its absorption performance and affordability. Based on the experimental results, the absorption performance for ammonia, ethylene oxide, and methylamine, which are hazardous and water-soluble gases among accident preparedness substances (APS), was tested by using ASEPN PLUS. Our results suggested although the efficiency dropped by about 5% to 25% when brine was used as an absorbent, it can be used at the low temperatures because the gas solubility increased with decreasing temperature. Therefore, if brine, as an alternative, is used at temperatures about 15 °C, it can operate efficiently and stably without deterioration in the absorption performance. Given our experimental results and design data on the absorbed amount and absorbent replacement period for major hazardous gases are utilized to prevent bubble columns from freezing, it can be commercially used for small and medium-sized enterprises because it can help reduce installation and operation costs.

scholarly journals CD Home Nanogrid: Avoiding Standby Consumption and Diminishing Ripple Amplitudes

2021 ◽  
Author(s):  
M.A. Cordova-Fajardo ◽  
E. Tututi
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Nonlinear Behavior ◽  
Experimental Results ◽  
Basic Unit ◽  
Local Market ◽  
Nonlinear Loads ◽  
Slow Development ◽  
Ripple Amplitude ◽  
Compact Fluorescent Lamp

<div>The nanogrids are the basic unit to develop more complex and stronger distributed systems. DC nanogrids allow a better performance and higher efficiency than the AC nanogrids. The lack of DC home appliances in the local market has resulted in a slow development of DC Home Nanogrids (DCHN). The Compact Fluorescent Lamp (CFL) and LED are used in power electronics as high efficiency and low cost lightning components. However, these devices represent a source of emission of harmonics in Alternating Current (AC) and Direct Current (DC) systems, due to their nonlinear behavior. In this paper a mathematical model for the nonlinear loads and experimental results of the voltage and current ripple in a DCHN are presented. The CFL and LED lamps are used as our nonlinear loads for test the model. The model explains well the experimental results of how the ripple amplitude is reduced. We also present the effect of decreasing the ripple amplitude when it is incorporated an induction stove in standby mode to the DCHN, which also is explained by the model.</div>

scholarly journals High-Efficiency Wavelet Compressive Fusion for Improving MEMS Array Performance

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1662 ◽  
Author(s):  
Siyuan Liang ◽  
Weilong Zhu ◽  
Feng Zhao ◽  
Congyi Wang
Keyword(s):  
Real Time ◽  
High Efficiency ◽  
Microelectromechanical Systems ◽  
Inertial Sensor ◽  
Low Cost ◽  
Rapid Development ◽  
Experimental Results ◽  
Zero Bias ◽  
Real Time Processing ◽  
Application Range

With the rapid development of microelectromechanical systems (MEMS) technology, low-cost MEMS inertial devices have been widely used for inertial navigation. However, their application range is greatly limited in some fields with high precision requirements because of their low precision and high noise. In this paper, to improve the performance of MEMS inertial devices, we propose a highly efficient optimal estimation algorithm for MEMS arrays based on wavelet compressive fusion (WCF). First, the algorithm uses the compression property of the multiscale wavelet transform to compress the original signal, fusing the compressive data based on the support. Second, threshold processing is performed on the fused wavelet coefficients. The simulation result demonstrates that the proposed algorithm performs well on the output of the inertial sensor array. Then, a ten-gyro array system is designed for collecting practical data, and the frequency of the embedded processor in our verification environment is 800 MHz. The experimental results show that, under the normal working conditions of the MEMS array system, the 100 ms input array data require an approximately 75 ms processing delay when employing the WCF algorithm to support real-time processing. Additionally, the zero-bias instability, angle random walk, and rate slope of the gyroscope are improved by 8.0, 8.0, and 9.5 dB, respectively, as compared with the original device. The experimental results demonstrate that the WCF algorithm has outstanding real-time performance and can effectively improve the accuracy of low-cost MEMS inertial devices.

Flocculation of Harmful Algal Blooms by Modified Fly Ash

2011 ◽  
Vol 347-353 ◽  
pp. 2090-2093
Author(s):  
Chun Guang Miao ◽  
Xiang Qin Wang ◽  
Hong Zhang
Keyword(s):  
Fly Ash ◽  
Hydrochloric Acid ◽  
Network Structure ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
High Efficiency ◽  
Low Cost ◽  
Experimental Results ◽  
Modified Fly Ash

The flocculants of fly ash(FA) and modified fly ash (mFA)were investigated in this study to evaluate their flocculation efficiencies in freshwater containing harmful algal blooms(HABs). The experimental results show that the efficiency of flocculation can be prominent improved by mFA.It was found that the fly ash modified by hydrochloric acid could form network structure bundle, algal cells were wrapped up through netting and bridging effect. So the method that removal of HABs with modified fly ash is low cost with high efficiency

scholarly journals CD Home Nanogrid: Avoiding Standby Consumption and Diminishing Ripple Amplitudes

2021 ◽  
Author(s):  
M.A. Cordova-Fajardo ◽  
E. Tututi
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Nonlinear Behavior ◽  
Experimental Results ◽  
Basic Unit ◽  
Local Market ◽  
Nonlinear Loads ◽  
Slow Development ◽  
Ripple Amplitude ◽  
Compact Fluorescent Lamp

<div>The nanogrids are the basic unit to develop more complex and stronger distributed systems. DC nanogrids allow a better performance and higher efficiency than the AC nanogrids. The lack of DC home appliances in the local market has resulted in a slow development of DC Home Nanogrids (DCHN). The Compact Fluorescent Lamp (CFL) and LED are used in power electronics as high efficiency and low cost lightning components. However, these devices represent a source of emission of harmonics in Alternating Current (AC) and Direct Current (DC) systems, due to their nonlinear behavior. In this paper a mathematical model for the nonlinear loads and experimental results of the voltage and current ripple in a DCHN are presented. The CFL and LED lamps are used as our nonlinear loads for test the model. The model explains well the experimental results of how the ripple amplitude is reduced. We also present the effect of decreasing the ripple amplitude when it is incorporated an induction stove in standby mode to the DCHN, which also is explained by the model.</div>

Microstructure and Mechanical Properties of Fe-Containing Al-Alloys Processed by a Rheo-Diecasting Process

2006 ◽  
Vol 519-521 ◽  
pp. 1251-1256
Author(s):  
X. Fang ◽  
G. Shao ◽  
Z. Fan
Keyword(s):  
Mechanical Properties ◽  
High Efficiency ◽  
Low Cost ◽  
Al Alloys ◽  
Experimental Results ◽  
Semisolid Slurry ◽  
Al Alloy ◽  
Twin Screw ◽  
Size And Morphology ◽  
Plate Morphology

Al-Fe compounds are usually present in the as-cast microstructure of Al-alloys as large needles or plates. As such, they have a detrimental effect on the mechanical properties of Al-alloys containing Fe, either as an impurity element or as an alloying addition. However, Fe-containing Al-alloys also offer attractive physical properties, such as improved stiffness, wear resistance and thermal resistance. If the needle and plate morphology of the Al-Fe compounds can be modified to a more compact morphology, with refined particle size and uniform distribution, the mechanical properties of Al-Fe based Al-alloys can be substantially improved, and therefore, they will find wider applications in many engineering sectors. A new semisolid metal processing technology, rheodiecasting (RDC), has been developed for production of Al-alloy components with high integrity. The RDC process innovatively combines the dispersive mixing power of the twin-screw mechanism, for the creation of high quality semisolid slurry, with the high efficiency, low cost nature of the high-pressure diecasting (HPDC) process for component shaping. In this paper, we present our experimental results on the effects of intensive melt shearing on the size and morphology of Al-Fe compounds in A380 alloys, with different levels of Fe additions. The experimental results have shown that intensive melt shearing during solidification can effectively change the particle shape from the usual needles and plates, to an equiaxed morphology. Samples which have undergone with melt shearing, exhibit much improved strength and ductility compared to those with the same level of Fe addition, but without exposure to melt shearing.

scholarly journals High-performance gallium nitride dielectric metalenses for imaging in the visible

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Meng-Hsin Chen ◽  
Wei-Ning Chou ◽  
Vin-Cent Su ◽  
Chieh-Hsiung Kuan ◽  
Hoang Yan Lin
Keyword(s):  
Gallium Nitride ◽  
Air Force ◽  
High Performance ◽  
High Efficiency ◽  
Low Cost ◽  
Wide Bandgap ◽  
Experimental Results ◽  
Successful Development ◽  
Spectral Bands ◽  
Visible Wavelengths

AbstractMetalens is one of the most promising applications for the development of metasurfaces. A wide variety of materials have been applied to metalenses working at certain spectral bands in order to meet the requirements of high efficiency and low-cost fabrication. Among these materials, wide-bandgap gallium nitride (GaN) is one of the most promising materials considering its advantages especially in semiconductor manufacturing. In this work, GaN has been utilized to fabricate the high-performance metalenses operating at visible wavelengths of 405, 532, and 633 nm with efficiencies up to 79%, 84%, and 89%, respectively. The homemade 1951 United State Air Force (UASF) resolution test chart has also been fabricated in order to provide resolvable lines with widths as small as 870 nm. As shown in the experimental results for imaging, the metalens designed at 405 nm can provide extremely high resolution to clearly resolve the smallest lines with the nano-sized widths in the homemade resolution test chart. These extraordinary experimental results come from our successful development in design and fabrication for the metalenses composed of high-aspect-ratio GaN nanoposts with nearly vertical sidewalls.

High efficiency of methylene blue removal using a novel low-cost acid treated forest wastes, Cupressus semperirens cones: Experimental results and modeling

2018 ◽  
Vol 37 (4) ◽  
pp. 504-513 ◽  
Author(s):  
Meryem Bounaas ◽  
Abdallah Bouguettoucha ◽  
Derradji Chebli ◽  
Abdelbaki Reffas ◽  
Intisar Harizi ◽  
...  
Keyword(s):  
Methylene Blue ◽  
High Efficiency ◽  
Low Cost ◽  
Experimental Results ◽  
Methylene Blue Removal

Removal of Ethyl Orange Dye Using Hybrid Chitosan and Zinc Oxide

2014 ◽  
Vol 67 (1) ◽  
Author(s):  
Norzita Ngadi ◽  
Mohamad Akmal Mahmud ◽  
Mazura Jusoh ◽  
Roshanida Abd Rahman ◽  
Hajar Alias
Keyword(s):  
Zinc Oxide ◽  
Azo Dye ◽  
Large Scale ◽  
High Efficiency ◽  
Low Cost ◽  
Mixing Time ◽  
Freundlich Isotherm ◽  
Water Soluble ◽  
Scale Production ◽  
Mixing Rate

Ethyl Orange is a type of water-soluble azo dye, which is widely used in the textile, printing, paper manufacturing, pharmaceutical and food industries. Due to a large-scale production and extensive application of azo dyes, it can cause considerable amount of polluted wastewater and can generate serious health-risk factors. Chitosan, a low cost adsorbent has been widely used to treat azo dye. Recent studies had discovered heterogeneous photocatalysis using semiconductors such as zinc oxide is quite applicable because of its ability to decolorize dye-containing wastewater more effectively. The purpose of this research is to hybridize the low-cost adsorbent chitosan and semiconductor zinc oxide to produce an adsorbent which has high efficiency for removing azo dye. The parameters that were used in this study are pH values (pH 5.0 to 9.0), temperature (25 to 60◦C) and the initial dye concentration (0.10 to 1.00 mg/L). The results obtained showed that hybrid chitosan and zinc oxide adsorbent had successfully decolorized ethyl orange dye in water. The optimum conditions for the highest removal of ethyl orange (85%) were achieved at following conditions; temperature of 60°C, using adsorbent containing 1 g of chitosan and 2.0wt % of zinc oxide, 1.0 mg/L of dye concentration, at pH 7 and 2 hours of mixing time with 130 rpm of mixing rate. In this study, the adsorption process was found to fit the Freundlich isotherm than of the Langmuir isotherm. 

Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

1985 ◽  
Vol 43 ◽  
pp. 364-365
Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason
Keyword(s):  
High Efficiency ◽  
Lattice Mismatch ◽  
Low Cost ◽  
Growth Conditions ◽  
Nonradiative Recombination ◽  
Device Structure ◽  
Si Substrates ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

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