Copper oxides obtained by CO2 laser irradiation of copper salts

1994 ◽  
Vol 9 (5) ◽  
pp. 1257-1263 ◽  
Author(s):  
C. Popescu ◽  
D. Fatu ◽  
Rodica Alexandrescu ◽  
I. Voicu ◽  
I. Morjan ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Laser Irradiation ◽  
Heating Rate ◽  
Co2 Laser ◽  
Continuous Wave ◽  
Copper Oxides ◽  
Thermal Heating ◽  
X Ray Diffraction ◽  
Copper Salts ◽  
X Ray

Various copper salts have been irradiated with the help of a continuous wave CO2 laser. In other experiments the same salts have been decomposed under a controlled heating rate, in a thermal balance, and copper oxide crystallites have been detected as the final product of both types of experiment. The measurements of crystallites performed with the help of x-ray diffraction exhibited differences between the two types of oxides: those obtained by laser irradiation as compared with the oxides obtained by thermal heating. The magnitude of this difference seems to depend on the laser quanta absorptivity of the initial salts. The results are consistent with those obtained previously on nickel oxides.

Fabrication and study the effect of the laser on the properties of the compound Tl2-xHgxBa2-ySryCa2Cu3O10+δ superconductor

2018 ◽  
pp. 168
Author(s):  
A. Kareem Dahash Ali ◽  
Nihad Ali Shafeek
Keyword(s):  
Transition Temperature ◽  
Solid State ◽  
Hydrostatic Pressure ◽  
Electrical Properties ◽  
Co2 Laser ◽  
Temperature Shift ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural And Electrical Properties

This study included the fabrication of    compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K  .When you shine a CO2 laser on the models in order to recognize the effect of the laser on these models showed the study of X-ray diffraction of these samples when preparing models with different concentrations of the values ​​of x, the best ratio of compensation is 0.2 which showed an increase in the values ​​of the dimensions of the unit cell a=b = 5.3929 (A °), c = 36.238 (A°). And the best transition temperature after shedding laser is TC=144 K. 

scholarly journals Carbon-coated magnetic particles increase tissue temperatures after laser irradiation

2015 ◽  
Vol 08 (05) ◽  
pp. 1550018 ◽  
Author(s):  
Shupeng Liu ◽  
Na Chen ◽  
Fufei Pang ◽  
Zhengyi Chen ◽  
Tingyun Wang
Keyword(s):  
Laser Irradiation ◽  
Magnetic Particles ◽  
Laser Energy ◽  
Thermal Therapy ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fbg Sensor ◽  
Transmission Electron ◽  
Carbon Coated

Purpose: This work focused on the investigation the hyperthermia performance of the carbon-coated magnetic particles (CCMPs) in laser-induced hyperthermia. Materials and methods: We prepared CCMPs using the organic carbonization method, and then characterized them with transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectrophotometry, vibrating sample magnetometer (VSM) and X-ray diffraction (XRD). In order to evaluate their performance in hyperthermia, the CCMPs were tested in laser-induced thermal therapy (LITT) experiments, in which we employed a fully distributed fiber Bragg grating (FBG) sensor to profile the tissue's dynamic temperature change under laser irradiation in real time. Results: The sizes of prepared CCMPs were about several micrometers, and the LITT results show that the tissue injected with the CCMPs absorbed more laser energy, and its temperature increased faster than the contrast tissue without CCMPs. Conclusions: The CCMPs may be of great help in hyperthermia applications.

scholarly journals Threshold of permanent cornea thermal damage due to incidental continuous wave CO2 laser irradiation

2010 ◽  
Vol 14 (2) ◽  
pp. 459-467 ◽  
Author(s):  
Mayada Tahir
Keyword(s):  
Laser Irradiation ◽  
Co2 Laser ◽  
Thermal Damage ◽  
Continuous Wave ◽  
Anterior Part ◽  
Outer Part ◽  
Human Cornea ◽  
Thermal Dose ◽  
Element Analysis ◽  
Reflex Blink

Cornea thermal damage due to incidental continuous wave CO2 laser irradiation is studied numerically based on bio-heat equation. The interaction of laser with tissue leads to a rapid temperature increased in target and the nearby tissue. As the temperature of the eye surface reaches 44?C, a sensation of pain will cause aversion response of the reflex blink and/or shifting away from the source of pain. The aim of the work is to predict numerically the threshold limit of incidental laser power that causes damage to the anterior part of the cornea, which can be healed within 2-5 days as long as damage is not exceeding the outer part of the eye (epithelium). A finite element analysis is used to predict temperature distribution through the cornea where the necroses region can be obtained using thermal dose equation. The thermal dose that required for damaging the cornea is predicted from previously published experimental data on rhesus monkeys and used later as a limit for shrinkage to human cornea. The result of this work is compared by international standard of safety and a good nearby result is obtained which verified the result of this work.

scholarly journals Copper oxide supported on graphene for phodegradation of rhodamine B

2015 ◽  
Vol 11 (4) ◽  
Author(s):  
Nurul Sahida Hassan ◽  
Nurul Jamilah Roslani ◽  
Aishah Abdul Jalil ◽  
Sugeng Triwahyono ◽  
Nur Fatien Salleh ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Copper Oxide ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Industrial Wastewater ◽  
Water Contamination ◽  
X Ray Diffraction ◽  
Composite Photocatalyst ◽  
X Ray ◽  
First Order

In recent years, dyes are one of the major sources of the water contamination that lead to environmental problems. For instance, Rhodamine B (RhB) which was extensively used as a colorant in textile industries is toxic and carcinogenic. Among many techniques, photocatalytic degradation become the promising one to remove those dyes from industrial wastewater. Recently, graphene has shown outstanding performance in this application due to its intrinsic electron delocalisation which promotes electron transport between composite photocatalyst and pollutant molecules. While, copper oxide (CuO) is well-known has a lower bandgap energies compared to other semiconductors. Therefore, in this study, copper oxide supported on graphene (CuO/G) was prepared and its photocatalytic activity was tested on degradation of RhB. The catalysts were characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) Spectroscopy. The results showed that the interaction between copper and graphene support could enhance the photocatalytic activity. The 5 wt% CuO/G was found to give the highest degradation (95%) of 10 mg L-1 of RhB solution at pH 7 using 1 g L-1 catalyst after 4 hours under visible light irradiation. The photodegradation followed the pseudo first-order Langmuir-Hinshelwood kinetic model. This study demonstrated that the CuO/G has a potential to be used in photocatalytic degradation of various organic pollutants.

scholarly journals Preparation and characterization of polyani-line/polyvinyl alcohol nanocomposite by laser irradiation

2017 ◽  
Vol 6 (4) ◽  
pp. 77
Author(s):  
N A M Shahin ◽  
S Abd El Mongy ◽  
R Kamal ◽  
A B El- Bially ◽  
A A Shabaka ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Relaxation Time ◽  
Polyvinyl Alcohol ◽  
Laser Irradiation ◽  
Imaginary Part ◽  
Electronic Transition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amorphous Nature

Polyaniline (PANI) - Polyvinyl alcohol (PVA) nanocomposite were prepared using laser irradiation method. X-ray diffraction results showed that, (PANI/PVA) nanocomposite exhibited amorphous nature of polymer. The electronic transition will be studied using Ultraviolet-Visible spectrometer (UV-Vis). The real part of dielectric constant (έ) and imaginary part (ε") were studied. Also, the relaxation time was calculated.

Effect of Al2O3 Xerogel on the Microstructure and the Properties of Laser Cladding Coating of Fe-Based Alloy

2010 ◽  
Vol 434-435 ◽  
pp. 743-746
Author(s):  
Shi Hai Zhao ◽  
Xiu Ming Jiang ◽  
Xu Guo Huai ◽  
Xiao Wei Fan
Keyword(s):  
Wear Resistance ◽  
Laser Cladding ◽  
Continuous Wave ◽  
Continuous Wave Laser ◽  
Dispersion Strengthening ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al2o3 Particles ◽  
Molten Liquid ◽  
Steel Substrates

Laser cladding Fe-based alloy coatings with 0, 3, 6, 9, 12 and 15% Al2O3 xerogel on 45 steel substrates were prepared by 5kWCO2 continuous wave laser. The effect of the content of Al2O3 xerogel on the microstructure, microhardness and wear resistance of the coatings was investigated by scan electron microscope, X-ray diffraction. The results show that the microstructure and properties were different when the content of Al2O3 xerogel changed. The addition of Al2O3 xerogel can enhance the fluidity of molten liquid and refine the microstructure. Adding adequate amount of Al2O3 xerogel to Fe-based alloy can improve the hardness and the wear resistance due to the nano-Al2O3 particles on surfaces and the dispersion strengthening and hardening of nano- Al2O3 particles.

scholarly journals Electrical, structural, and photocatalytic properties of copper oxide nanowire

2020 ◽  
Vol 44 (7-8) ◽  
pp. 471-474
Author(s):  
Azadeh Jafari ◽  
SAA Terohid ◽  
Alireza Kokabi ◽  
Amir Moradiani
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Copper Oxide ◽  
Growth Temperature ◽  
Photocatalytic Properties ◽  
X Ray Diffraction ◽  
Direct Oxidation ◽  
Oxide Nanowires ◽  
X Ray ◽  
Scanning Electron

Using a direct oxidation method in a horizontal quartz tube, copper oxide nanowires are grown on a Cu substrate. In order to investigate the growth temperature effects on the structural, morphological, electrical, and photocatalytic properties of the copper oxide nanowires, X-ray diffraction, scanning electron microscopy, a KEITHLEY 2361 system, and a homemade photoreactor are used. The X-ray diffraction results show that both CuO and Cu2O phases are formed, and while increasing the growth temperature, the crystallinity is improved and the intensity of most of the diffraction peaks increases. The scanning electron microscopy images at different growth temperatures show that the number, density, and length of the copper oxide nanowires on pre-formed micro-scaled grains increase, when the growth temperature increases to 700°C and sharper nanowires with average diameters of 1–3 µm grow on the surface. Also I–V curves show that by raising the growth temperature, the conductivity of the samples increases. In addition, the photocatalytic activities are studied by photocatalytic degradation of Congo red dye, and based on these results, the sample grown at 700°C with the highest number and density of the nanowires showed the best photocatalytic performance and electrical conductivity. The results can be used to guide better understanding of the growth behavior of copper oxide nanowires and can be useful for the development of novel photocatalytic nanodevices.

scholarly journals Evaluation of Hydrogen Yield Evolution in Gaseous Fraction and Biochar Structure Resulting from Walnut Shells Pyrolysis

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6359
Author(s):  
Elena David
Keyword(s):  
Heating Rate ◽  
Pyrolysis Temperature ◽  
Walnut Shell ◽  
Hydrogen Yield ◽  
X Ray Diffraction ◽  
Fast Heating ◽  
X Ray ◽  
Walnut Shells ◽  
Water Vapors ◽  
Gaseous Fraction

Conversion experiments of wet and dry walnut shells were performed, the influence of moisture content on the hydrogen yield in the gas fraction was estimated and the resulted biochar structure was presented. Measurements of the biochar structures were performed using X-ray diffraction and scanning electron microscopy methods. The results demonstrate that heating rate played a key role in the pyrolysis process and influenced the biochar structure. Under fast heating rate, the interactions between the water vapors released and other intermediate products, such as biochar was enhanced and consequently more hydrogen was generated. It could also be observed that both biochar samples, obtained from wet and dry walnut shells, had an approximately smooth surface and are different from the rough surface of the raw walnut shell, but there are not obvious differences in shape and pores structure between the two biochar samples. The increasing of the biochar surface area versus pyrolysis temperature is due tothe formation of micropores in structure. The biochar shows a surface morphology in the form of particles with rough, compact and porous structure. In addition the biochar structure confirmed that directly pyrolysis of wet walnut shells without predried treatment has enhanced the hydrogen content in the gas fraction.

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