Radiotracer Studies of Engine Deposit Formation

1958 ◽  
Vol 50 (3) ◽  
pp. 341-342 ◽  
Author(s):  
Clifton Sechrist ◽  
Harold Hammen
Keyword(s):  
Deposit Formation ◽  
Engine Deposit

scholarly journals Investigation into the Impact of the Composition of Ethanol Fuel Deposit Control Additives on Their Effectiveness

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 604
Author(s):  
Zbigniew Stępień ◽  
Grażyna Żak ◽  
Jarosław Markowski ◽  
Michał Wojtasik
Keyword(s):  
Test Procedure ◽  
Dosage Level ◽  
Operational Parameters ◽  
Combustion Chambers ◽  
Deposit Formation ◽  
Fuel Injectors ◽  
Chemical Structures ◽  
Critical Areas ◽  
Engine Deposit ◽  
The Impact

An increasing percentage of ethanol in fuel leads to significant changes in polarity and solubility, which makes conventional gasoline deposit control additives (DCAs) difficult to dissolve in ethanol fuels, resulting in the formation of deposits on engine elements. Critical areas of deposit formation in an engine are constituted by inlet valves, combustion chambers, and fuel injectors. As a consequence, operational parameters of the engine are disturbed to a large extent by the total effect of the deposits. To prevent the aforementioned phenomena, in the operation of engines fueled with ethanol-containing blends, it is necessary to use specifically prepared DCAs. The paper briefly presents a process of development of DCAs dedicated to high-ethanol fuels. Each of the prepared DCA formulations contained a substance having detergent-emulsifying properties (referred to in the text as DEM), a carrier oil, and a solvent. The composition and ratios of components used in the DCA, by testing their effectiveness in engine deposit formation, are verified. A motor station and a test procedure developed for this purpose were used. In search of alternative solutions to conventional polyisobutyleneamines (PIBA) and polyetheramines (PEA) surfactants, which have good solubility in hydrocarbons but not in ethanol, a substance with a benzoxazine structure and a Mannich base were synthesized. Their chemical structures were confirmed by nuclear magnetic resonance (NMR) DCAs were developed, and the effectiveness of their action was verified. Moreover, attention was paid to the dosage level of the DEM and the carrier oil in the DCA. Finally, it was confirmed in the studies carried out that DCAs used for improvement of conventional hydrocarbon engine gasolines are not efficient enough when used in E85 fuels. In the case of the latter, DCAs that have been specifically developed for such fuels should be used, because they have a different chemical structure, and are soluble in the ethanol-gasoline mixture in any ratio of both components.

Numerical simulation of atomic layer deposition for thin deposit formation in mesoporous substrate

AIChE Journal ◽  
2021 ◽  
Author(s):  
Liwei Zhuang ◽  
Peter Corkery ◽  
Dennis T. Lee ◽  
Seungjoon Lee ◽  
Mahdi Kooshkbaghi ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Atomic Layer Deposition ◽  
Atomic Layer ◽  
Deposit Formation ◽  
Layer Deposition

scholarly journals Complement C5 is not critical for the formation of sub-RPE deposits in Efemp1 mutant mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Donita L. Garland ◽  
Eric A. Pierce ◽  
Rosario Fernandez-Godino
Keyword(s):  
Macular Degeneration ◽  
Retinal Pigment ◽  
Age Related Macular Degeneration ◽  
Deposit Formation ◽  
Genetic Ablation ◽  
Age Related ◽  
Complement Dysregulation

AbstractThe complement system plays a role in the formation of sub-retinal pigment epithelial (RPE) deposits in early stages of age-related macular degeneration (AMD). But the specific mechanisms that connect complement activation and deposit formation in AMD patients are unknown, which limits the development of efficient therapies to reduce or stop disease progression. We have previously demonstrated that C3 blockage prevents the formation of sub-RPE deposits in a mouse model of EFEMP1-associated macular degeneration. In this study, we have used double mutant Efemp1R345W/R345W:C5-/- mice to investigate the role of C5 in the formation of sub-RPE deposits in vivo and in vitro. The data revealed that the genetic ablation of C5 does not eliminate the formation of sub-RPE deposits. Contrarily, the absence of C5 in RPE cultures promotes complement dysregulation that results in increased activation of C3, which likely contributes to deposit formation even in the absence of EFEMP1-R345W mutant protein. The results also suggest that genetic ablation of C5 alters the extracellular matrix turnover through an effect on matrix metalloproteinases in RPE cell cultures. These results confirm that C3 rather than C5 could be an effective therapeutic target to treat early AMD.

scholarly journals Effects of thermal treatments on characteristics and morphological variations in the deposits of urea-SCR systems

2021 ◽  
Author(s):  
Sadashiva Prabhu S ◽  
Kapilan Natesan ◽  
Nagaraj Shivappa Nayak
Keyword(s):  
Cyanuric Acid ◽  
Catalytic Reduction ◽  
Morphological Changes ◽  
Water Solution ◽  
Slight Variation ◽  
Gravimetric Analysis ◽  
Oxides Of Nitrogen ◽  
Deposit Formation ◽  
X Ray ◽  
Exhaust Gases

AbstractSelective catalytic reduction (SCR) systems are employed by automobile manufacturers for the abatement of environmental pollutants like oxides of nitrogen (NOx) emitted from exhaust gases of diesel engines. In SCR, the urea-water solution (UWS) is injected to exhaust gases in the form of a spray to generate the reducing agent NH3. Deposit formation at lower temperatures is a major concern with this technology. The deposits not only create backpressure but also leak NH3 to the environment as they deplete. It is very important to know the depletion characteristics of deposits formed at lower temperatures in order to assess the NH3 leakage to the environment when the engine exhaust gases attain higher temperatures. In the present work, deposits formed at a low-temperature range of 150–200°C for continuous run along with UWS injection were investigated. Additionally, they were aged at 300°C in the absence of UWS to check the variation in characteristics with the rise of temperature. By gravimetric analysis, it is inferred that the deposits formed at higher pre-age temperatures are less prone to depletion as the temperature increases. The elemental analysis using energy-dispersive X-ray spectroscopy (EDX) indicates slight variation in carbon, nitrogen and oxygen compositions for all the pre-age conditions. As an extended study, the byproducts at pre-age and post-age conditions were investigated through X-ray diffraction (XRD). The compounds like cyanuric acid (CYA) and biuret were not observed when pre-age samples were aged at 300°C. Instead, the compounds like ammelide, ammeline, triuret and melamine were observed. Scanning electron microscope (SEM) study revealed morphological changes in both pre-age and post-age samples. Further, the crystallinity variations were also observed for the changes in the heating cycles during deposit formation. The gravimetric analysis of deposits in pre-age and post-age conditions helps in predicting the amount of deposits for transient load cycles.

Influence of sintering on deposit formation during pool boiling of calcium sulphate solutions

2010 ◽  
Vol 34 (8) ◽  
pp. 1439-1447 ◽  
Author(s):  
M. Esawy ◽  
M.S. Abd-Elhady ◽  
M.R. Malayeri ◽  
H. Müller-Steinhagen
Keyword(s):  
Pool Boiling ◽  
Calcium Sulphate ◽  
Deposit Formation

Investigation of deposit formation and its characterization for a pulverized bituminous coal power plant

2016 ◽  
Vol 141 ◽  
pp. 225-234 ◽  
Author(s):  
Selahattin Babat ◽  
Reinhold Spörl ◽  
Jörg Maier ◽  
Günter Scheffknecht
Keyword(s):  
Power Plant ◽  
Bituminous Coal ◽  
Deposit Formation ◽  
Coal Power Plant ◽  
Coal Power
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