scholarly journals (?m 10.6) Design study for Reserve of laser CO2

2014 ◽  
Vol 11 (2) ◽  
pp. 560-563
Author(s):  
Baghdad Science Journal
Keyword(s):  
Total Energy ◽  
Co2 Laser ◽  
Room Temperature ◽  
High Efficiency ◽  
Low Cost ◽  
Optical Design ◽  
The Other ◽  
Receiver System ◽  
Normal Error ◽  
Focal Shift

In this paper , the CO2 laser receiver system is designed and studied, with wavelength laser 10.6 ?m in room temperature , and to evaluate the performance and discussion it via the package of optical design (ZEMAX), from its output the Spot Diagram is measured through RMS ,and from the Ray fan plot , the aberrations is found which is the normal error for the best focus named (under corrected ) , the other output was the Geometric Encircled Energy in the spot diagram . and found that the radius of spot diagram at 80% (R80%) from the total energy ,and focal shift .The designed system have high efficiency and low cost .

Production of novel applicable derivatives from biodiesel glycerin

2018 ◽  
Vol 7 (4) ◽  
pp. 323-333
Author(s):  
Afshin Abrishamkar ◽  
Armin Franz Isenmann ◽  
Amin Abrishamkar
Keyword(s):  
Equilibrium State ◽  
Formic Acid ◽  
Allyl Alcohol ◽  
Room Temperature ◽  
Low Cost ◽  
The Other ◽  
Biodiesel Production ◽  
Esterification Reaction ◽  
Efficient Production ◽  
Successful Completion

Abstract Glycerin (glycerol) is a co-product of biodiesel production that is widely produced and is available at a low cost. To date, various applications have been investigated and introduced for biodiesel glycerin. In this study, a number of valuable products were produced using biodiesel glycerin and formic acid as the main reactants. Allyl alcohol is one of the valuable chemicals produced from glycerin monoformate. Efficient production of this product requires successful completion of the first section of the reaction, which is an equilibrium reaction. The highest feasible yield achieved was about 83% (based on the consumption of formic acid) at 120–140°C without the addition of any catalysts. Also, the esterification reaction was further investigated at room temperature, where the equilibrium state was reached with a yield of 55% after only 4 h. Moreover, the addition of urea to the reaction with the aim of producing the other two side products, i.e. diformyl urea and glycerin carbonate, in addition to glycerin monoformate, was studied. The results showed that considerable amounts of applicable byproducts, e.g. formamid, are also produced, making the process even more economical.

scholarly journals A low-cost, high-efficiency, new generation material for fog harvesting fumed silica-doped polypropylene

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
İ. Afşin Kari̇per
Keyword(s):  
Surface Tension ◽  
Fumed Silica ◽  
Arid Regions ◽  
High Efficiency ◽  
Low Cost ◽  
The Other ◽  
Clean Water ◽  
Silica Doping ◽  
New Generation ◽  
Fog Collector

AbstractThis study describes the development of a fog collector material for fog harvesting. Polypropylene (PP) doped with fumed silica (0–2%) was punctured at equal intervals and exposed to fog produced by a humidifier. The amount of water harvested by each sample was measured using an ultrasonic fogger. Polypropylene doped with 1% fumed silica was most effective at harvesting water, and collected almost 19–20 times more water than pure polypropylene. This improvement is due to the surface tension, which decreased from 16.754 mN/m (pure PP) to 13.512 and 9.992 mN/m (0.5% and 1% fumed silica, respectively). On the other hand, when fumed silica doping exceeded 1%, this increased the polymer’s surface tension, measured as 20.6 and 38.1 mN/m for 1.5 and 2% fumed silica doping. We therefore propose fog harvesting using 1% fumed silica-doped polypropylene as a low-cost method for collecting clean water in arid regions.

Study of Film Layer Structure and Resistance on High Strength Room Temperature Blackening

2014 ◽  
Vol 687-691 ◽  
pp. 4183-4186
Author(s):  
Yu Feng Zhang ◽  
Xi Zhang ◽  
Min Rui Li ◽  
Bo Wang
Keyword(s):  
Wear Resistance ◽  
Room Temperature ◽  
High Efficiency ◽  
Treatment Time ◽  
Layer Structure ◽  
Low Cost ◽  
High Strength ◽  
P System ◽  
Short Treatment ◽  
Film Layer

In this paper, the high strength room temperature blackening film on steel surface were prepared, the structure and the forming principle of the film were studied. The procedure of the Cu-Se-P system high strength composition blackening was researched, and the factors that affect the wear resistance of the film were analyzed [1]. The experiment shows that the procedure have many virtues, such as short treatment time, high efficiency, low cost, high adhesive strength, perfect wear resistance, which posed a new approach for blackening of machine parts.

scholarly journals Bromide Induced Room‐Temperature Formation of Photoactive Formamidinium‐Based Perovskite for High‐Efficiency, Low‐Cost Solar Cells (Solar RRL 4∕2019)

Solar RRL ◽  
2019 ◽  
Vol 3 (4) ◽  
pp. 1970045
Author(s):  
Xinding Lv ◽  
Xuemei Dong ◽  
Zhili Ye ◽  
Junshuai Zhou ◽  
Fei Deng ◽  
...  
Keyword(s):  
Solar Cells ◽  
Room Temperature ◽  
High Efficiency ◽  
Low Cost

Bromide Induced Room‐Temperature Formation of Photoactive Formamidinium‐Based Perovskite for High‐Efficiency, Low‐Cost Solar Cells

Solar RRL ◽  
2018 ◽  
Vol 3 (4) ◽  
pp. 1800313 ◽  
Author(s):  
Xinding Lv ◽  
Xuemei Dong ◽  
Zhili Ye ◽  
Junshuai Zhou ◽  
Fei Deng ◽  
...  
Keyword(s):  
Solar Cells ◽  
Room Temperature ◽  
High Efficiency ◽  
Low Cost

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.

Electron microscope studies of the plastic deformation of ternary alloys based on GaAs

1990 ◽  
Vol 48 (4) ◽  
pp. 1120-1120
Author(s):  
R. Haswell ◽  
U. Bangert ◽  
P. Charsley
Keyword(s):  
Plastic Deformation ◽  
Electron Microscope ◽  
Room Temperature ◽  
Stacking Faults ◽  
The Other ◽  
Ternary Alloys ◽  
Dislocation Mobility ◽  
Semiconducting Materials ◽  
Micro Indentation

A knowledge of the behaviour of dislocations in semiconducting materials is essential to the understanding of devices which use them . This work is concerned with dislocations in alloys related to the semiconductor GaAs . Previous work on GaAs has shown that microtwinning occurs on one of the <110> rosette arms after indentation in preference to the other . We have shown that the effect of replacing some of the Ga atoms by Al results in microtwinning in both of the rosette arms.In the work to be reported dislocations in specimens of different compositions of Gax Al(1-x) As and Gax In(1-x) As have been studied by using micro indentation on a (001) face at room temperature . A range of electron microscope techniques have been used to investigate the type of dislocations and stacking faults/microtwins in the rosette arms , which are parallel to the [110] and [10] , as a function of composition for both alloys . Under certain conditions microtwinning occurs in both directions . This will be discussed in terms of the dislocation mobility.

Improvement of Ti/RuO2–IrO2 Anode Lifetime and Electrocatalytical Properties by Using an Eco-Friendly Thermal Decomposition Method Using Polyvinyl Alcohol as Solvent

2019 ◽  
Author(s):  
Charlys Bezerra ◽  
Géssica Santos ◽  
Marilia Pupo ◽  
Maria Gomes ◽  
Ronaldo Silva ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Polyvinyl Alcohol ◽  
High Efficiency ◽  
Electrochemical Impedance ◽  
Pechini Method ◽  
Low Cost ◽  
Charge Transfer Resistance ◽  
Transfer Resistance ◽  
Calcination Temperatures ◽  
Service Lifetime

<p>Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO<sub>2</sub> and IrO<sub>2</sub> have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes with improved properties that can be further extended to synthesise other MMO compositions.</p>

Clustering-Triggered Efficient Room Temperature Phosphorescence from Nonconventional Luminophores

2019 ◽  
Author(s):  
Shuyuan Zheng ◽  
Taiping Hu ◽  
Xin Bin ◽  
Yunzhong Wang ◽  
Yuanping Yi ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Efficiency ◽  
Spin Orbit Coupling ◽  
Design Rationale ◽  
Emission Mechanism ◽  
Room Temperature Phosphorescence ◽  
Electronic Interactions ◽  
Energy Gaps ◽  
Theoretical Results

Pure organic room temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Here we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boost the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5% is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results would spur the future fabrication of nonconventional phosphors, and moreover should advance understanding of the underlying emission mechanism.<br>

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