scholarly journals Effect of the Fuel Equivalence Ratio on the Mechanisms of Thiophene Oxidation in Water Vapor at Increased Density of the Reagents

ACS Omega ◽  
2021 ◽  
Author(s):  
Oxana N. Fedyaeva ◽  
Andrey V. Shishkin ◽  
Anatoly A. Vostrikov
Keyword(s):  
Water Vapor ◽  
Equivalence Ratio ◽  
Thiophene Oxidation

Spectral Radiation Analysis of Premixed Oxy-Methane Flames

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
A. S. M. Arifur Chowdhury ◽  
Naznin Jahan Afrose ◽  
Norman Love
Keyword(s):  
Carbon Dioxide ◽  
Water Vapor ◽  
Carbon Capture ◽  
Equivalence Ratio ◽  
Radiative Heat ◽  
Carbon Dioxide Emission ◽  
Methane Combustion ◽  
Spectral Intensity ◽  
Spectral Radiation ◽  
Methane Flames

For a hydrocarbon burning with oxygen, the resulting exhaust stream is composed mainly of carbon dioxide and water vapor. This exhaust allows for easier carbon capture and sequestration since the water can be condensed out. Another advantage is the significant reduction of NOx since much of the nitrogen found in air-fired systems is eliminated. Although beneficial, many of the exhaust gas products' radiative heat transfer characteristics are unknown. Motivated by this, this paper focuses on the spectral radiation measurement of premixed oxy-methane combustion flames. This is important for combustion system designers since radiative heat from the flame is significant for oxy-flames. This study is conducted by varying equivalence ratio, firing input, and CO2 recirculation ratio. The spectral radiation of premixed oxy-methane flames is collected from 1.2 μm to 5 μm wavelengths. During the experimental study, it is found that the water vapor emits at 1.4 μm, 1.85 μm, and 2.5 μm wavelengths. A short band of carbon dioxide emission is detected at 1.96 μm. Three other carbon dioxide radiation maxima are observed at the proximity of 2.71 μm, 2.85 μm, and 4.38 μm. The study revealed that the spectral intensity of CO2 and H2O for oxy-methane combustion increases almost five times compared to the air-methane combustion at stochiometric condition. It is also found that the spectral intensity decreases as the equivalence ratio increases. The spectral radiative emission intensity increases as the firing input increases. Another observation includes the fact that spectral intensity increases up to five times when 60% CO2 is recirculated as a diluent in the flame.

scholarly journals Effect of Water Vapor Injection on the Distributions of Equivalence Ratio and the NO Emission Reduction in a CI Engine

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4248
Author(s):  
Min ◽  
Suh
Keyword(s):  
Water Vapor ◽  
Equivalence Ratio ◽  
Exhaust Emission ◽  
Intake Port ◽  
Compression Ignition Engine ◽  
Intake Process ◽  
Consumption Values ◽  
Vapor Injection ◽  
The Rich ◽  
Ultrasonic Humidifier

The objective of this study was to investigate the influence of a water vapor injection into the intake port of a small compression ignition engine and analyze the effect of the collisions between the water particles and the injected fuel on combustion and exhaust emission performances. To simulate the water vapor by the ultrasonic humidifier in the numerical analysis, the water particles were introduced into the cylinder through an intake port during the intake process, and the amount was varied from 10% to 30% of the injected fuel mass per stroke. When the water vapor was injected into the intake port, the rich equivalence ratio region was distributed in the center of cylinder. In addition, the ISNO (indicated specific nitrogen oxide) values decreased up to 46% more than the values for the condition without the water-vapor-injection. However, the ISSoot (indicated specific soot) exhibited similar values in any conditions. For starts of energizing timing that were BTDC (before top dead center) 25 deg and 15 deg, the ISFC (indicated fuel consumption) values decreased with increased portions of water vapor. However, in the case of BTDC 05deg, the ignition delay was too long, which deteriorated combustion performance.

New Design for a Differentially Pumped Hydration Chamber for a Siemens IA

1971 ◽  
Vol 29 ◽  
pp. 44-45
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Water Vapor ◽  
Electron Diffraction ◽  
Water Vapor Pressure ◽  
Biological Materials ◽  
Thin Membrane ◽  
Reliable System ◽  
System A ◽  
Water Films ◽  
Aperture Opening

Electron microscopy and diffraction of biological materials in the hydrated state requires the construction of a chamber in which the water vapor pressure can be maintained at saturation for a given specimen temperature, while minimally affecting the normal vacuum of the remainder of the microscope column. Initial studies with chambers closed by thin membrane windows showed that at the film thicknesses required for electron diffraction at 100 KV the window failure rate was too high to give a reliable system. A single stage, differentially pumped specimen hydration chamber was constructed, consisting of two apertures (70-100μ), which eliminated the necessity of thin membrane windows. This system was used to obtain electron diffraction and electron microscopy of water droplets and thin water films. However, a period of dehydration occurred during initial pumping of the microscope column. Although rehydration occurred within five minutes, biological materials were irreversibly damaged. Another limitation of this system was that the specimen grid was clamped between the apertures, thus limiting the yield of view to the aperture opening.

Hydration Chamber for Jeolco 200 Kv Microscope

1970 ◽  
Vol 28 ◽  
pp. 542-543
Author(s):  
V. R. Matricardi ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscope ◽  
Water Vapor ◽  
Vapor Pressure ◽  
Pressure Gradient ◽  
Room Temperature ◽  
List Type ◽  
Type Number ◽  
Equilibrium Vapor Pressure

In order to observe room temperature hydrated specimens in an electron microscope, the following conditions should be satisfied: The specimen should be surrounded by water vapor as close as possible to the equilibrium vapor pressure corresponding to the temperature of the specimen.The specimen grid should be inserted, focused and photo graphed in the shortest possible time in order to minimize dehydration.The full area of the specimen grid should be visible in order to minimize the number of changes of specimen required.There should be no pressure gradient across the grid so that specimens can be straddled across holes.Leakage of water vapor to the column should be minimized.

Warm and freeze-fracture of cotton seed radicles

1987 ◽  
Vol 45 ◽  
pp. 984-985
Author(s):  
E. L. Vigil ◽  
E. F. Erbe
Keyword(s):  
Thin Film ◽  
Water Vapor ◽  
Fracture Surface ◽  
Membrane Structure ◽  
Room Temperature ◽  
Freeze Fracture ◽  
Longitudinal Axis ◽  
Fracture Plane ◽  
Cotton Seeds ◽  
Condensed Water

In cotton seeds the radicle has 12% moisture content which makes it possible to prepare freeze-fracture replicas without fixation or cryoprotection. For this study we have examined replicas of unfixed radicle tissue fractured at room temperature to obtain data on organelle and membrane structure.Excised radicles from seeds of cotton (Gossyplum hirsutum L. M-8) were fractured at room temperature along the longitudinal axis. The fracture was initiated by spliting the basal end of the excised radicle with a razor. This procedure produced a fracture through the tissue along an unknown fracture plane. The warm fractured radicle halves were placed on a thin film of 100% glycerol on a flat brass cap with fracture surface up. The cap was rapidly plunged into liquid nitrogen and transferred to a freeze- etch unit. The sample was etched for 3 min at -95°C to remove any condensed water vapor and then cooled to -150°C for platinum/carbon evaporation.

LINE SHAPE PARAMETERS OF WATER VAPOR TRANSITIONS IN THE 3645-3975 cm−1 REGION

2017 ◽  
Author(s):  
Mary Smith ◽  
Thomas Blake ◽  
Robert Sams ◽  
Candice Renaud ◽  
Bastien Vispoel ◽  
...  
Keyword(s):  
Water Vapor ◽  
Line Shape ◽  
Shape Parameters
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