Characterization of Defect Induced Multilayer Graphene

2017 ◽  
Vol 7 (3) ◽  
pp. 1452
Author(s):  
Marriatyi Morsin ◽  
Suhaila Isaak ◽  
Marlia Morsin ◽  
Yusmeeraz Yusof
Keyword(s):  
Surface Roughness ◽  
Flow Rate ◽  
Intensity Ratio ◽  
Oxygen Plasma ◽  
Defect Density ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Multilayer Graphene ◽  
Flow Rates

<p class="Abstract">A study of oxygen plasma on multilayer graphene is done with different flow rates. This is to allow a controlled amount of defect fabricated on the graphene. Results from the study showed that the intensity ratio of defect between D peak and G peak was strongly depended on the amount of oxygen flow rate thus affected the 2D band of the spectra. The inter-defect distance L<sub>D </sub>≥ 15 nm of each sample indicated that low-defect density was fabricated. The surface roughness of the multilayer graphene also increased and reduced the conductivity of the multilayer graphene.</p>

Effect of Oxygen Flow Rate on the Memristive Behavior of Reactively Sputtered TiO2 Thin Films

2014 ◽  
Vol 1024 ◽  
pp. 64-67 ◽  
Author(s):  
Nur Syahirah Kamarozaman ◽  
Muhamad Uzair Shamsul ◽  
Sukreen Hana Herman ◽  
Wan Fazlida Hanim Abdullah
Keyword(s):  
Thin Films ◽  
Flow Rate ◽  
Rf Magnetron Sputtering ◽  
Deposition Process ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Switching Behavior ◽  
Memristive Behavior ◽  
Effect Of Oxygen

The paper presents the memristive behavior of sputtered titania thin films on ITO substrate. Titania thin films were deposited by RF magnetron sputtering method while varying the oxygen flow rate of (O2/ (O2 + Ar) x100 = 10, 20 and 30 %) during deposition process. The effect of oxygen flow rate to the structural properties was studied including the physical thickness, and also the effect towards switching behavior. It was found that sample deposited at 20 % oxygen flow rate gave better memristive behavior compared to other samples, with larger ROFF/RON ratio of 9. The characterization of memristive behavior includes the effect of electroforming process and successive of I-V measurements are discussed.

Effects of oxygen partial pressure on the microstructure, electrical and optical properties of the Sn-doped In2O3 thin films

2018 ◽  
Vol 32 (24) ◽  
pp. 1850284
Author(s):  
Xiaochan Liu ◽  
Yukai An ◽  
Zhen Lin ◽  
Jiwen Liu
Keyword(s):  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Ultraviolet Light ◽  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Good Sensitivity ◽  
Flow Rates ◽  
Ito Film ◽  
Ito Films

The effects of oxygen partial pressure on the microstructure, electrical and photo-sensitive properties of the Sn-doped In2O3 (ITO) films deposited by different Ar–O2 flow rates (10:0.4, 10:1, 10:1.8 and 10:3) were investigated systematically by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), Hall effect, UV-Vis and optical measurements. The XRD and SEM measurements show that the ITO film deposited at oxygen flow rate of 0.4 sccm prefers to (400) orientation and has a rough sawtooth-shaped surface. However, the ITO films deposited at oxygen flow rates of 1 sccm, 1.8 sccm and 3 sccm prefer to (222) orientation and exhibit a flat smooth surface. The conductivity, mobility and photosensitive property of ITO films are also sensitive to oxygen flow rate. The ITO film deposited at oxygen flow rate of 0.4 sccm has a high carrier concentration (up to [Formula: see text] cm[Formula: see text]) and mobility (16.7 cm2/vs), low resistivity [Formula: see text], and a long response time but good sensitivity to ultraviolet light. It can be concluded that the surface morphology plays a dominant role in sensitivity to ultraviolet light. The good sensitivity of ultraviolet light is gained from the ITO film with sawtooth-shaped surface.

Application of ANN and ANFIS in prediction of color strength of plasma-treated wool yarns dyed with a natural colorant

2020 ◽  
Vol 49 (3) ◽  
pp. 171-180 ◽  
Author(s):  
Aminoddin Haji ◽  
Pedram Payvandy
Keyword(s):  
Plasma Treatment ◽  
Flow Rate ◽  
Oxygen Plasma ◽  
Correlation Coefficients ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Color Strength ◽  
Treatment Variable ◽  
Content Type ◽  
Natural Dyeing

Purpose Despite the increasing popularity of natural dyeing of textiles, the low substantivity between the fibers and the natural dyes is a problem. Several methods have been used to overcome this problem. In this study, wool fibers were pretreated with oxygen plasma under different conditions and dyed with the extract of grape leaves. The purpose of this study is to investigate the effects of plasma treatment parameters on the color strength of the dyed samples using artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) and evaluate the ability of these methods for predicting the color strength. Design/methodology/approach Woolen yarns were modified under different conditions of oxygen plasma treatment. Oxygen flow rate, power and time were considered as the treatment variable factors. Plasma-treated samples were dyed under constant conditions with the extract of grape leaves as a natural dye. ANN and ANFIS were applied to model and analyze the effect of plasma treatment parameters on the color strength of the dyed samples. Findings The results showed that increasing all the plasma treatment process variables, including oxygen flow rate, power and time increased the color strength of the dyed samples. The results showed that the developed ANN and ANFIS could accurately predict the experimental data with correlation coefficients of 0.986 and 0.997, respectively. According to the obtained correlation coefficients, ANFIS had a higher accuracy in prediction of the results of this study compared with the ANN and RSM models (correlation coefficient = 0.902, from our previous study). Originality/value This study uses ANN and ANFIS for predicting color strength of naturally dyed textiles for the first time. The use of computational intelligence for the optimization and prediction of the effects plasma treatment for the improvement of natural dyeing of wool is another novelty of this study.

scholarly journals An Analysis of the Performance of a Variable Venturi-type Oxygen Mask

1980 ◽  
Vol 8 (1) ◽  
pp. 44-51 ◽  
Author(s):  
D. F. Woolner ◽  
J. Larkin
Keyword(s):  
Oxygen Concentration ◽  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Weighted Mean ◽  
Flow Rates ◽  
Oxygen Mask ◽  
Inspired Oxygen ◽  
Theoretical Performance

The theoretical performance of the Hudson Multivent mask is considered. A method is described of determining the flow-weighted mean inspired oxygen concentration produced by the mask. Using this method, it was found that the inspired oxygen concentration was predictable only at the 24% setting using the recommended flow rates, but that increasing the supplied-oxygen flow rates above the recommended levels resulted in the return of predictable function. At settings above 30% predictable function was found to be unlikely, whatever the supplied oxygen flow rate. Recommendations are made regarding the use of this device.

scholarly journals Mathematical Modeling of Postcombustion in an Electric Arc Furnace (EAF)

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 547
Author(s):  
Niloofar Arzpeyma ◽  
Mikael Ersson ◽  
Pär G. Jönsson
Keyword(s):  
Mathematical Modeling ◽  
Flow Rate ◽  
Electric Arc Furnace ◽  
Electric Arc ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Bath Surface ◽  
Arc Furnace ◽  
Molten Bath ◽  
Flow Rates

Numerical modeling was used to study the capability of postcombustion in an electric arc furnace (EAF) equipped with virtual lance burners. The CO flow rate at the molten bath surface was estimated using the off-gas data obtained close to the outlet of an EAF. Then, the effect of the secondary oxygen flow rate on postcombustion was studied. The results show a CO flow rate of 0.6 kg·s−1 and 0.8 kg·s−1 for operation modes of burner and burner + lancing. Increase of the secondary oxygen flow rates of 60% and 70% result in 17% and 7% increase in the postcombustion ratio (PCR) for the burner and burner lancing modes, respectively.

Effect of Oxygen Flow Rate on the Characteristics of RF Sputtered ZnO Thin Films

2021 ◽  
Vol 903 ◽  
pp. 91-97
Author(s):  
Pathan Parhana ◽  
M.V. Lakshmaiah
Keyword(s):  
Thin Films ◽  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Zno Thin Films ◽  
Visible Range ◽  
Zno Films ◽  
Flow Rates ◽  
X Ray ◽  
Effect Of Oxygen

Zinc Oxide (ZnO) thin films were deposited on glass substrate by radio frequency (RF)reactive magnetron sputtering technique at variable Oxygen flow rates while Argon flow rates waskept constant. The effect of oxygen flow rate on structural, electrical, optical properties of nanostructured ZnO thin films were investigated by X-ray diffractometer, scanning eletron microscopy(SEM), Hall effect measurements and UV-Visible spectrophotometer. X-ray diffraction (XRD) datareveals films are polycrystalline hexagonal structure with (002) peak as a preferred orientation andcrystallite size was found to be in range12 nm-16 nm.The electrical resistivity of films decreasesfrom 10-1 Ω-cm to 10-2 Ω-cm. All deposited ZnO thin films shows high transmittance above 95% inthe visible range 360 nm-800 nm. The optical band gap and refractive indices have been calculatedusing UV-Vis transmission spectra. Oxygen gas flow rates found to have large impact onoptoelectronic properties of ZnO films.

scholarly journals Effect of Oxygen Flow Rate on the Optical, Electrical, and Mechanical Properties of DC Sputtering ITO Thin Films

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Chuen-Lin Tien ◽  
Hong-Yi Lin ◽  
Chih-Kai Chang ◽  
Chien-Jen Tang
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Residual Stress ◽  
Surface Roughness ◽  
Flow Rate ◽  
Optical Transmittance ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Ito Thin Films ◽  
Effect Of Oxygen

This study presents the effect of oxygen flow rate on the optical, electrical, and mechanical properties of indium tin oxide (ITO) thin films prepared by the DC magnetron sputtering technique. The oxygen flow rate was varied from 10 to 50 sccm. The ITO thin films deposition under different oxygen flow rates exhibits different properties. We used an optical spectrometer to measure the optical transmittance and a four-point probe instrument to determine the resistivity. A home-made Twyman-Green interferometer was used to evaluate residual stress and a microscopic interferometer was used to measure the surface roughness of ITO thin films. The experimental results show that the average optical transmittance is larger than 85% in visible range; the electrical resistivity has a minimum 6.85×10-4 ohm-cm for the oxygen flow of 10 sccm. The residual stress is varied from −0.15 GPa to −0.34 GPa in the range of 10–50 sccm. The root-mean-square (rms) surface roughness is changed from 2.64 nm to 2.74 nm as the oxygen flow rate increases. The results show that the oxygen flow rate has significant influence on the electrical resistivity, residual stress, and surface roughness of the ITO thin film.

scholarly journals Growth, Structural and Optical Properties of DC Reactive Magnetron Sputtered TixSi1-xO2 Thin Films

2015 ◽  
Vol 57 ◽  
pp. 182-190
Author(s):  
Suresh Addepalli ◽  
Uthanna Suda
Keyword(s):  
Thin Films ◽  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Binding Energies ◽  
Core Level ◽  
Oxygen Flow ◽  
Reactive Magnetron ◽  
Flow Rates ◽  
X Ray ◽  
Deposited Films

Thin films of TixSi1-xO2 were deposited on silicon and quartz substrates by DC reactive magnetron sputtering of Ti80Si20 composite target at different oxygen flow rates. The deposited films were characterized for their chemical composition and core level binding energies using X-ray photoelectron spectroscope, surface morphology with scanning electron microscope, optical absorption with spectrophotometer and refractive index by ellipsometer. The thickness of the deposited films was 100 nm. The oxygen content in the films increased with increase of oxygen flow rate. Films with Ti0.7Si0.3O2 were achieved at oxygen flow rates ≥ 8 sccm. X-ray diffraction studies indicated the grown of amorphous films. X-ray photoelectron spectra of the films showed the characteristic core level binding energies of TixSi1-xO2. Optical band gap of the films decreased from 4.15 to 4.07 eV with increase of oxygen flow rate from 2 sccm to 10 sccm respectively.

scholarly journals ANALYSIS OF BIOGAS COMPONENT PRODUCTION DURING ANAEROBIC DIGESTION OF SOUR CABBAGE IN MICROAERATION CONDITIONS UNDER DIFFERENT pH CONDITIONS

2021 ◽  
Author(s):  
Gaweł Sołowski
Keyword(s):  
Anaerobic Digestion ◽  
Hydrogen Production ◽  
Flow Rate ◽  
Suspended Solid ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Volatile Suspended Solid ◽  
Flow Rates ◽  
Ph Conditions ◽  
Oxygen Addition

In the article, were checked influences of microaeration, pH, and VSS (Volatile Suspended Solid) for sour cab-bage anaerobic digestion. Results fermentation of sour cabbage under the condition of small oxygen addition are presented in this research can be classified as dark fermentation or hydrogenotrophic anaerobic digestion. The investigations were carried out for two concentrations 5 g VSS /L and 10 g VSS /L of sour cabbage at pH 6.0. The oxygen flow rates (OFR) for 5 g VSS /L were in the range of 0.53 to 3.3 mL/h for obtaining 2% to 8% of oxygen. In cases of low pH and microaeration, ethylene production was observed at a level below 0.05% in biogas. The highest volume of hydrogen for 5 g VSS/L was obtained for flow rate 0.58 O2 mL/h, giving hydrogen concentration in biogas in the range of 0 to 20%. For VSS 5 g/L and oxygen flow rate 0.58 mL/h; 0.021 L of hydrogen is produced per gram of VSS. In this case, VSS 10 g/L and oxygen flow rate 1.4 mL/h at pH 6.0, 0.03 L of hydrogen is generated per gram. Microaeration from 0.58 mL/h to 0.87 mL/h was propitious for hydrogen production at 5 g VSS/L of sour cabbage and 1.4 mL/h for 10 g/L. Another relevant factor is the volatile suspended solid factor of sour cabbage that caused optimal hydrogen production at VSS 89.32%.

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