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.

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.

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>

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 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%.

scholarly journals The Design of Oxygen Concentration and Flowrate in CPAP

2019 ◽  
Vol 1 (1) ◽  
pp. 6-10
Author(s):  
Ade Putra ◽  
Tri Bowo Indrato ◽  
Liliek Soetjiatie
Keyword(s):  
Oxygen Content ◽  
Oxygen Concentration ◽  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Measuring Instruments ◽  
Oxygen Levels ◽  
Oxygen Analyzer ◽  
Oxygen Measurement ◽  
Measurement Rate

Measuring oxygen concentration and measuring the flow of oxygen is a tool used to measure the percentage of oxygen content and oxygen flow rate in CPAP. This tool uses the OCS-03F sensor, with Arduino NANO processors then displayed on the 2X16 character LCD. Measuring the percentage of oxygen content and oxygen flow rate is carried out on CPAP for 5 measurements. The research and manufacture of this module uses the Pre-experimental method with the After Only Design design, which examines the "Oxygen Analyzer", which results in measurements compared to the traced tools to obtain high accuracy values. Based on the results of measurements on the CPAP tool at Dr. Soetomo Surabaya Hospital with oxygen level settings of 21%, 30%, 40%, 50% 60%, 70%, 80%, 90%, 100% while setting the oxygen measurement rate 1L/m, 2L /m, 3L/m, 4L/m, 5L/m, 6L/m, 7L//m, 8L/m, 9L/m 10L/m. Each measurement was carried out 5 times. For the measurement of oxygen levels the biggest error value is 5% and the smallest -0,06% while for the measurement of oxygen flow rate the biggest error value is 4% and the smallest is 0%. Based on the results of the analysis of the manufacture of oxygen levels and oxygen flow rates, it can be concluded that the manufacture of oxygen concentration measuring instruments and oxygen flow rate can work well.

Effects of Reaction Conditions on Deposition of Ferrites from Alkaline Metal Hydroxide Gels

1997 ◽  
Vol 495 ◽  
Author(s):  
Karl F. Schoch ◽  
Theodore R. Vasilow
Keyword(s):  
Flow Rate ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Metal Hydroxides ◽  
X Ray ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Mg Content

ABSTRACTFormation of ferrites from aqueous solution of metal salts is a well known process involving precipitation of metal hydroxides followed by oxidation of the resulting gel. The purpose of the present work was to determine the effects oxygen flow rate on the progress of the reaction and on the structure and properties of the resulting precipitate. The reaction was carried out at 70°C with pH of 10.5 and oxygen flow rate of 2,4, or 8 standard liters per hour. The progress of the reaction was monitored by following the oxidation-reduction potential of the solution, which changes dramatically after the Fe(II) is consumed. The reaction rate increased with increasing oxygen flow rate. The Mg content of the precipitate was lower than that of the reaction mixture, possibly because of the pH of the reaction mixture. X-ray diffraction and infrared spectroscopy confirmed formation of a ferrite under these conditions.

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