• The Journal of Natural Sciences
• /
• v.1
• /
• pp.47-59
• /
• 1987

The thermal decomposition mechanism of BaTiO($$C_2$$O_4$)_2$ $4H_2$O has been investigated employing TG, DTG, and DTA techniques. The intermediate compounds and the gaseous products of decomposition were examined by IR spectrometer and X-ray analyser. The decomposition proceeds through five steps. The first step which is the dehydration of the tetrahydrate is followed by the decomposition of oxalate groups. During the second decomposition, half a mole of carbon monoxide is evolved. The oxalate groups are completely destroyed in the range $260~460^{\circ}C$, resulting in the formation of a carbonate which retains free carbon dioxide in the matrix . the final decomposition of the carbonate takes place between $650~750^{\circ}C$ and yields $BaTiO_3$.

• Clinical and Experimental Pediatrics
• /
• v.64 no.10
• /
• pp.525-530
• /
• 2021

Background: Exposure to air pollution (gaseous pollutants and/or particulate matter) has been associated with the incidence, prevalence, and mortality of type 1 diabetes (T1D). Purpose: To examine the quantitative relationship between air pollutant emissions and the incidence of T1D. Methods: We examined the association between the incidence of T1D and type 2 diabetes (T2D) in 2017 as well as that of T1D in patients younger than 15 years in 2016 with "emissions of air-polluting substances from stationary and mobile sources by regions of the Russian Federation in 2016" as reported by the Federal Diabetes Register of Russia downloaded from the Russian government website (http://www.mnr.gov.ru/docs/gosudarstvennye_doklady/o_sostoyanii_i_ob_okhrane_okruzhayushchey_sredy_rossiyskoy_federatsii/). Results: The incidence of T1D across all ages in each region of the Russian Federation correlated with the total air pollutants emitted in the region each year (r=0.278, P=0.013). The incidence of T2D was also correlated with the amount of air pollutants (r=0.234, P=0.037) and the incidence of T1D (r=0.600, P<0.001) in each country. Similarly, the incidence of T1D in patients younger than 15 years correlated with the total air pollutants emitted each year in each region (r=0.300, P=0.011). Conclusion: The quantitative relationship between the total air pollutants emitted and the incidence of T1D and T2D in the Russian Federation suggests that air pollution contributes to the development of T1D and T2D.

• Applied Chemistry for Engineering
• /
• v.32 no.2
• /
• pp.205-213
• /
• 2021

The present study aimed to determine the effect of co-pyrolysis of sawdust biomass and scrap tyre waste employing different blending ratios of sawdust to waste tyre such as 100:0, 75:25, 50:50, 25:75, and 0:100. The thermochemical characterization of feedstocks was carried out by employing the proximate, ultimate analysis, and thermogravimetric (TGA) analyses, calorific values, and scanning electron microscope coupled with energy dispersive x-ray analysis (SEM-EDX) to select the blending ratio having better bioenergy potential amongst the studied ratios. The blending ratio of 25:75 (sawdust to waste tyre) was selected for the co-pyrolysis study in a fixed-bed pyrolysis reactor system based on its solid biofuels properties such as heating value (30.18 MJ/kg), and carbon (71.81 wt%) and volatile matter (63.82 wt%) contents. The pyrolysis temperatures were varied as 500, 600 and 700 ℃ while the other parameters such as heating rate and nitrogen flowrate were maintained at 30 ℃/min and 0.5 L/min respectively. The bio-oil yields as 31.9, 47.1 and 61.2 wt%, bio-char yields as 34.5, 34.2 and 31.4 wt% and gaseous product yields as 33.6, 18.60 and 7.3 wt% at the pyrolysis temperatures of 500, 600 and 700 ℃ respectively were obtained. The blends of sawdust and waste tyres showed the improved energy characteristics which could provide the solution for the beneficial management of sawdust and scrape tyre wastes via co-pyrolysis processing.

• Korean Journal of Organic Agriculture
• /
• v.28 no.4
• /
• pp.579-589
• /
• 2020

This study was carried out to evaluate the effect of rye as green manure crop on the improvement of soil environment and reduction of Phytophthora blight in red pepper of open field where Phytophthora blight occurred frequently. Soil physical properties such as bulk density and porosity were increased in rye cultivation. In addition, gaseous was increased but liquid was decreased compared with conventional cultivation. The analysis of phospholipid fatty acids extracted from soil showed that rye cultivation significantly increased relative abundance of microbial community and ratio of aerobic to anaerobic bacteria. Furthermore, ratio of saturated to unsaturated fatty acids and cyclo-fatty acids to precursor. the indicators of increasing in environmental stresses, were reduced in rye cultivated field. Occurrence of Phytophthora blight in rye cultivation was reduced 30.7% compared with conventional cultivation. These results suggest that rye cultivation in red pepper of open field where Phytophthora blight occurred can improve soil environment and reduce damage of Phytophthora blight.

• Journal of Climate Change Research
• /
• v.6 no.4
• /
• pp.311-318
• /
• 2015

Emission characteristics from charbroiling of four different meats (beef, port, duck and chicken) in a pilot-scale cooking facility were investigated in this study. The analyzed air pollutants include gaseous species (CO, NO, $SO_2$, $NH_3$ and PAHs) as well as particulate matters (TSP, $PM_{10}$, $PM_{2.5}$ and black carbon). The emission factors of $PM_{10}$ and PAHs were in the range of 3~47 g-PM/kg-meat and 0.6~11.41 mg-PAHs/kg-meat, respectively, depending on the type of a meat. In addition, the results also revealed that the high ratio of $PM_{2.5}$ to TSP in a meat charbroiling should be considered to design and to operate air pollution control devices.

• The Plant Pathology Journal
• /
• v.35 no.5
• /
• pp.437-444
• /
• 2019

Chlorine dioxide ($ClO_2$) has been widely used as an effective disinfectant to control fungal contamination during postharvest crop storage. In this study, Fusarium oxysporum f. sp. batatas SP-f6 from the black rot symptom of sweetpotato was isolated and identified using phylogenetic analysis of elongation factor 1-${\alpha}$ gene; we further examined the in vitro and in vivo inhibitory activities of $ClO_2$ gas against the fungus. In the in vitro medium tests, fungal population was significantly inhibited upon increasing the concentration and exposure time. In in vivo tests, spore suspensions were drop-inoculated onto sweetpotato slices, followed by treatment using various $ClO_2$ concentrations and treatment times to assess fungus-induced disease development in the slices. Lesion diameters decreased at the tested $ClO_2$ concentrations over time. When sweetpotato roots were dip-inoculated in spore suspensions prior to treatment with 20 and 40 ppm of $ClO_2$ for 0-60 min, fungal populations significantly decreased at the tested concentrations for 30-60 min. Taken together, these results showed that $ClO_2$ gas can effectively inhibit fungal growth and disease development caused by F. oxysporum f. sp. batatas on sweetpotato. Therefore, $ClO_2$ gas may be used as a sanitizer to control this fungus during postharvest storage of sweetpotato.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.3
• /
• pp.905-914
• /
• 2019

In this study, The PMF model was used to identify pollutant sources and their contribution to pollution sources of $PM_{2.5}$. The contribution of A city to each source was 19.8% for Secondary Sulfate, followed by Mobile 19.5%, Industry 16.0%, Biomass Buring 14.1%, Secondary Nitrate 14.1%, Oil Combustion 11.6%, Aged Sea Salt 2.6%, Soil 2.5% and so on. Sulfate and Ammonium concentrations were the highest contributing sources in the source profile, which was analyzed to be Secondary Aerosols produced by Photochemical Reactions of gaseous precursors (SOx and ammonia gas) in the atmosphere.

• Fire Science and Engineering
• /
• v.33 no.1
• /
• pp.99-104
• /
• 2019

In a gas system fire extinguishing system, extinguishing agents are usually stored with approximately 280 bar at $21^{\circ}C$ and are released at approximately 8 MPa through the decompression valve and orifice to quickly suppress the fire. When extinguishing agents are discharged, they cause a loud noise (approximately 140 dB), which can damage electronics, such as hard disk drives (HDDs). Therefore, the noise is becoming a serious issue in the gas extinguishing system. The method of the noise reduction by adding an absorbent is most general and in this study, the thickness of the absorbent was as a selected design variable. The noise level at the observation point and the flow characteristics inside the nozzle were numerically calculated and analyzed using the commercial code ANSYS CFX ver. 18.1.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.6
• /
• pp.593-601
• /
• 2021

Primary cilia on kidney tubular cells play crucial roles in maintaining structure and physiological function. Emerging evidence indicates that the absence of primary cilia, and their length, are associated with kidney diseases. The length of primary cilia in kidney tubular epithelial cells depends, at least in part, on oxidative stress and extracellular signal-regulated kinase 1/2 (ERK) activation. Hydrogen sulfide (H₂S) is involved in antioxidant systems and the ERK signaling pathway. Therefore, in this study, we investigated the role of H₂S in primary cilia elongation and the downstream pathway. In cultured Madin-Darby Canine Kidney cells, the length of primary cilia gradually increased up to 4 days after the cells were grown to confluent monolayers. In addition, the expression of H₂S-producing enzyme increased concomitantly with primary cilia length. Treatment with NaHS, an exogenous H₂S donor, accelerated the elongation of primary cilia whereas DL-propargylglycine (a cystathionine γ-lyase inhibitor) and hydroxylamine (a cystathionine-β-synthase inhibitor) delayed their elongation. NaHS treatment increased ERK activation and Sec10 and Arl13b protein expression, both of which are involved in cilia formation and elongation. Treatment with U0126, an ERK inhibitor, delayed elongation of primary cilia and blocked the effect of NaHS-mediated primary cilia elongation and Sec10 and Arl13b upregulation. Finally, we also found that H₂S accelerated primary cilia elongation after ischemic kidney injury. These results indicate that H₂S lengthens primary cilia through ERK activation and a consequent increase in Sec10 and Arl13b expression, suggesting that H₂S and its downstream targets could be novel molecular targets for regulating primary cilia.

• Korean Journal of Agricultural Science
• /
• v.48 no.3
• /
• pp.589-596
• /
• 2021

Nitrogen applied to soil is highly prone to leaching and volatilization leading to gaseous emissions of nitrous oxide (N₂O) and ammonia (NH₃) which are of great environmental concern. Usage of biochar to reduce the discharge of nitrogen to the environment has attracted much interest in the recent past. Biochar is produced by pyrolyzing various biomasses under oxygen-limited conditions. Biochar is a carbonized material with high adsorptive powers for not only plant nutrients but also heavy metals. The objective of this study was to investigate the adsorption characteristics of NH₄-N onto biochar made from pine needles. The biochar was produced at various pyrolysis temperatures including 300, 400 and 500℃ and holding times of 30 and 120 minutes. The Langmuir isotherm was used to evaluate the adsorption test results. The chemical properties of the biochar varied with the pyrolysis conditions. In particular, the pH, EC and total carbon content increased with the increasing pyrolysis conditions. The rate of adsorption of NH₄-N by the biochar decreased with the increasing pyrolysis conditions. Of these conditions, biochar that was pyrolyzed at 300℃ for 30 minutes showed the highest adsorption rate of approximately 0.071 mg·g^-1. Thus, the use of biochar pyrolyzed at low temperatures with a short holding time can most efficiently reduce ammonia emissions from agricultural land.