Analysis of Total Hydrocarbon Exceeding Standard in Oil Chromatogram of a 500kV Main Transformer

Oil chromatographic analysis is widely used in transformer fault diagnosis However, the problem of excessive total hydrocarbons in the oil chromatogram caused by the failure of the transformer submersible pump is different from the failure of the transformer body. Technicians need to be able to accurately identify these two types of failure. For this problem, this article proposes a method of judging by manually starting and stopping the submersible pump and monitoring the change law of the transformer chromatographic data. This article first finds out suspicious submersible pumps through current data. Subsequently, the operator starts and stops the submersible pump and monitors the change law of the transformer chromatographic data. From this, the correlation between the start or stop of the submersible pump and the chromatographic data was found. Finally, the effectiveness of this method is verified by the submersible pump disassembly inspection and simulated live test.

Concentration of some Polycyclic Aromatic Hydrocarbons in soil samples of Kirkuk province, Iraq

In order to evaluate the quantity of twelve PAHs (Naphthalene, Tetraphan and Acenaphthylene Fluorene, Phenanthrene, Anthracene, Pyrene, Benzo [a] Anthracene, Ovalene, Chrysene, Benzo [a] fluoranthene and DiBenzo [ah] Anthracene) in the soil samples from Kirkuk province, seven sites (Ras El-Gesr, Benja Ali, Wahed Hozeran, North Oil Company (NOC), Lillan, Kubri and Chimen) were selected using Gas Chromatography (GC) during the autumn 2017 and winter 2018. The results showed that the highest concentration of individual hydrocarbons during the autumn season was for the Acenaphthylene compound in the NOC site 131.19 μg/kg, and for Naphthalene compound, was 100.543μg/kg. The NOC recorded the highest concentration of total hydrocarbons 891.65 μg/kg. For the winter season, the highest concentration of polycyclic aromatic hydrocarbons was recorded for the Fluorene compound at the NOC site 79.19 μg/kg. Fluorene and Naphthalene compounds achieved the highest averages for the season (43.24 and 42.984 μg/kg) respectively, and recorded the location of the NOC, the highest summation of total hydrocarbons amounted to 609.77 μg/kg.

Purple Corn Anthocyanin Affects Lipid Mechanism, Flavor Compound Profiles, and Related Gene Expression of Longissimus Thoracis et Lumborum Muscle in Goats

The current study aimed to investigate the effect of anthocyanins on muscle flavor compound profiles in goats. Goats in three groups were fed a basic diet or a diet supplemented with 0.5 g/d or 1 g/d anthocyanin-rich purple corn pigment (PCP). Compared to the control group, plasma total cholesterol was significantly decreased (p < 0.05) in the anthocyanin groups. The feeding of anthocyanin increased (p < 0.05) flavor compound types and total alcohol level, whereas it decreased (p < 0.05) total hydrocarbons, aromatics, esters, and miscellaneous compounds in the longissimusthoracis et lumborum muscle (LTL). Adding PCP to the diet enriched (p < 0.05) vegetal, herbaceous, grease, and fruity flavors compared to the control group. The 0.5 g/d PCP group had increased (p < 0.05) abundance of peroxisome proliferator-activated receptor gamma, but there was a decreased (p < 0.05) level of lipoprotein lipase in LTL. Collectively, this study indicated that anthocyanin can improve mutton flavor by decreasing plasma lipid parameters and by modulating the abundance of several flavor-related genes of goats.

Composition of gas from pyrolysis of Estonian oil shale under N2 and CO2

Studying the evolution of gas during the decomposition process of oil shale provides information about the changes of gas composition and understand the mechanism of pyrolysis process. A few number of studies focused on using CO2 atmosphere to observe the effect of sweep gas on pyrolysis products. Fischer assay method was used to analyze the pyrolysis of Estonian kukersite oil shale under CO2, CO2/steam, N2 and N2/steam. The gaseous products were collected offline using a sample bag. Gas chromatography was performed to investigate the evolution of C1-C3 gases, H2, CO2 and CO. Subsequently, the results from each test were analyzed and compared. Our results show that in comparison with N2, pyrolysis in CO2 increased the production of alkanes and hydrocarbon gases. Also, generation of CH4 and CO gases were enhanced under CO2, while composition of H2 did not significantly change in the gaseous products for both environments. For the tests in presence of steam, the results show that unlike the N2 atmosphere, CO2/steam decreased the production of total hydrocarbons, H2, CO2 and CO.

Effect of air pollution on gout development: a nationwide population-based observational study

Summary Objective To investigate the effect of air pollution on gout development. Methods A total of 170318 participants were enrolled. These pollutants were considered: carbon monoxide (CO), fine particulate matter 2.5 (PM2.5), total hydrocarbons (THC) and methane (CH4). The yearly average concentrations were calculated from 2000 to 2011. Univariate and multivariate analyses by Cox proportional hazard regression models were adopted to estimate hazard ratios for gout in the Q2–Q4 concentrations of air pollutants compared with the Q1 concentration. Results In THC, relative to the Q1 concentration, the risk of gout was higher in participants exposed to the Q2–Q4 concentrations [adjusted hazard ratio (aHR), 1.10 with 95% confidence interval (CI), 1.01–1.19 in the Q2 concentration of THC; aHR, 4.20 with 95% CI, 3.93–4.49 in the Q3 concentration of THC; aHR, 5.65 with 95% CI, 5.29–6.04 in the Q4 concentration of THC]. In regard to CH4, when the Q1 concentration was defined as the reference, the risks of gout were increased for participants exposed to the Q2, Q3 and Q4 concentrations (aHR, 1.16 with 95% CI, 1.06–1.26 in the Q2 concentration of CH4; aHR, 2.37 with 95% CI, 2.20–2.55 in the Q3 concentration of CH4; aHR, 8.73 with 95% CI, 8.16–9.34 in the Q4 concentration of CH4). Conclusions Association between air pollution and risk of gout was noted.

Effect of different levels of ethanol addition on performance, emission, and combustion characteristics of a gasoline engine

In this study, a four-stroke, naturally aspirated, single-cylinder, spark ignition engine was operated with neat gasoline fuel. In-cylinder pressure, performance, and emission values were obtained at full load and 2400-r/min constant engine speed. Using these values, a single-dimensional theoretical model was calibrated. A Kistler spark plug–type pressure sensor was used to obtain in-cylinder pressure. After validation of this single-dimensional theoretical model obtained by the help of a commercial engine analysis software (AVL-Boost), different levels of ethanol addition (2.5%, 5%, 10%, 15%, and 20%) into gasoline were analyzed and compared with neat gasoline fueled conditions. According to obtained results, NO x emissions increased with incremental amount of ethanol. The CO and total hydrocarbons emissions decreased; however, they can be controlled using after-treatment systems such as three-way catalyst.

Evaluating the In-Service Emissions of High-Mileage Dedicated Methanol-Fueled Passenger Cars: Regulated and Unregulated Emissions

This paper reports the regulated, unregulated, and particle number emissions from six high-mileage, China-4 compliant, dedicated methanol taxis over the new European driving cycle. Compared to new vehicles, carbon monoxide, total hydrocarbons, and nitrogen oxides emissions from in-use methanol taxis increased by 76.1%, 40.2%, and 179.8%, respectively. Still, they managed to meet China-4, indicating good in-service conformity. In the test fleet, the test vehicles with longer mileage inclined to emit higher carbon monoxide and total hydrocarbons emissions. Formaldehyde emissions from these field-aged taxis ranged from 1.06 to 2.33 mg/km, which were similar to or lower than those from previously reported pre-Euro-5 gasoline vehicles. One of the six test vehicles produced extraordinarily high unburned methanol emissions, which was about ten times higher than the rest of the properly operating vehicles due to possible misfire, suggesting that unburned methanol will be the primary stress for future methanol applications. Compared to the regulated emissions, formaldehyde and unburned methanol emissions deteriorated at faster rates along with catalyst aging. Particle number emissions from these methanol taxis remained low even after high-mileage driving, suggesting the compatibility of methanol fueling in future particle number compliance.