• Journal of Korean Society for Atmospheric Environment
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• v.26 no.2
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• pp.118-136
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• 2010

Photochemical characteristics of ozone ($O_3$) and its precursors such as $O_3$ budget and $O_3-NO_x$-VOC sensitivity were analyzed in different physico-chemical properties of air masses around the Mexico City Metropolitan Area (MCMA) using aircraft observations during March 2006. The physico-chemical properties of air masses were categorized into 5 groups: boundary layer (BL), biomass burning (BB), free tropospheric continent (FTCO) and marine (FTMA), and Tula industrial complex (TIC). Results from the $O_3$ budget analysis indicated that $O_3$ production for BL, FTCO, and FTMA (for BB and TIC) was mainly controlled by a photochemical production pathway, a reaction of NO with $HO_2$ (with $RO_2$), while the main pathway of photochemical $O_3$ destruction for BL, FTCO, and FTMA (for BB and TIC) was a reaction of $HO_2$ with $O_3$ (of $H_2$ with $O^1$(D)). In addition, most of air mass categories (especially FTCO) were estimated to be $NO_x$-sensitive for $O_3$ production with lower $NO_y$, higher ratios of the other indicator species (e.g., $O_3/(NO_y-NO_x$), $H_2O_2/HNO_3$, etc.), and the lower removal rate of radicals ($\leq$0.5) by the reaction of OH with $NO_2$ than those of the VOC-sensitive condition.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.1
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• pp.23-30
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• 1999

The changes of soil physico-chemical properties were investigated in the sandy loam soil amended with various application rates of chicken and pig manure composts. After repeated application of the composts for 3 years, total nitrogen content in soil treated with applied 120Mg/ha of chicken and pig manure composts was 2.1 g/kg equally. Organic matter content was 38.8 and 39.1 g/kg, available phosphate content was 602 and 585 mg/kg, and cation exchange capacity(CEC) was 10.1 and 12.4 cmol/kg in chicken and pig manure compost 120 Mg/ha treatment, respectively. Exchangeable K, Ca, Na, Mg contents, and electrical conductivity(EC) increased with the amount of applied compost. Also, with increased amount of applied compost, porosity of soil increased, but hardness, bulk density and Y value decreased.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.6
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• pp.884-888
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• 2003

Proteolytic enzymes are used for meat tenderization, an important process with regard to consumer preference. The proteolytic enzyme, IVRIN was isolated from the plant Cucumis pubescens W and its effect on physico-chemical properties and lipid profile of thigh and breast muscle of culled, desi and broiler birds was studied. Fifty-gram meat was treated with IVRIN containing 32.5 mg enzyme protein at $60^{\circ}C$ for 20 min. The pH of IVRIN treated meat was decreased significantly (p<0.01) and the effect was more pronounced in breast than thigh muscle. The water holding capacity (WHC) was increased significantly (p<0.01) in broiler as compared to desi and culled bird, and in breast compared to thigh muscle. IVRIN failed to produce any impact on muscle fiber diameter (MFD). The MFD of desi was significantly higher (p<0.01) than broiler and culled birds. The total lipid concentration in thigh and breast muscle of desi was lower (p<0.01) than broiler and culled birds, latter being similar in this respect. The cholesterol content was lower (p<0.01) in breast than thigh muscle, in broiler than desi and culled and in IVRIN treated than untreated meat samples. The phospholipid concentration was unaffected by IVRIN. Broiler and culled birds exhibited more phospholipid content than desi birds.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.335-340
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• 2016

Soil organic carbon plays an important role on soil physico-chemical properties and crop yields in paddy soil. However, there is little information on the soil organic carbon under different forage cultivation during winter season in rice paddy. In this study, we investigated the soil organic carbon and physico-chemical properties in 87 fields of paddy soil cultivated with Barley, rye, and Italian ryegrass (IRG) as animal feedstock during winter season. Organic carbon was 12.9, 14.3, and $16.9g\;C\;kg^{-1}$ in soil with barley, rye, and IRG cultivation, respectively. Among rice-forage cultivation systems, the rice+IRG cropping system was 19.5% higher than in the mono-rice cultivation. Bulk density ranged from 1.17 to $1.28g\;cm^{-3}$ irrespective of cropping systems, and had strongly negative correlation with the soil organic carbon in the rice+IRG cropping system. Carbon storage in rice+IRG cropping systems was average $29.6Mg\;ha^{-1}$ at 15 cm of soil depth, which was 20.4 and 10.3% higher than those of barley and rye cultivation. Increasing carbon storage in paddy soil contributed to the fertility for following rice cultivation. This results indicated that IRG cultivation during winter season could be an alternative and promising way to enhance soil organic carbon content and fertility of paddy soil.

• Journal of Ocean Engineering and Technology
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• v.19 no.4 s.65
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• pp.42-48
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• 2005

The sediment of Shihwa Lake contains an abundant quantity of cohesive sediments. The transport processes of the cohesive sediments are complex and difficult to predict, quantitatively. The cohesive sediments are the primary reason for the pollution of the environment and water quality in the coastal region. In this study, a column test has been performed. In order to quantify the settling velocities of sediment from Shihwa Lake, an experiment was conducted using a specially designed 1.8m tall settling column. A series of settling tests and physico-chemical property tests on Shihwa Lake cohesive sediments has been conducted to investigate the correlation between settling properties and their physico-chemical properties, which are represented as grain size distribution, mineralogical composition, and percentage oj organic contents. Experimental results of physico-chemical property tests show that Shihwa Lake sediments are relatively large in average grain $size(74\mu m)$ contain very small organic $material(6\%)$, and are dominantly composed of Quarts, which has relatively low cohesion. Thus, Shihwa Lake sediments might be specified as those whose settling properties are more influenced by gravity than cohesion. It is concluded that the magnitude of settling velocities of muddy sediments can be quite different, regionally, and it implies that field or laboratory experiments for settling velocity measurement should be preceded over the numerical modeling of muddy sediment transport, in order to obtain the reliable prediction results for a given specific site.

• Korean journal of food and cookery science
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• v.14 no.2
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• pp.177-181
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• 1998

The changes of the physico-chemical characteristics of potato and chicken frying oil with frying number were examined. The changes in temperatures of frying oil during the potato flying were greater than that during the chicken frying. The weight loss of potato during deep frying was about 21.9% and about 12.3% for chicken. The acid values and conjugated dienoic acid values of the potato and chicken frying oils increased with increased frying number. Their values were greater in the chicken frying oil than in the potato frying oil. The peroxide values of frying oil did not change regularly as frying number increased. But iodine values of the frying oils decreased with increased frying number. Linoleic acid content of the frying oil decreased, whereas oleic acid content increased with frying number.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.16-20
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• 2003

This study was conducted to investigate the effect of dietary mugwort powder on the physico-chemical characteristics of pork. Pig was randomly selected based on three dietary treatments: 1) control(commercial feed) 2) T1(commercial feed supplemented with 1% mugwort powder) and 3) T2(commercial feed with 3% mugwort powder). They were fed with the experimental diets for 30 days and slaughtered. Meat samples were wrap packaged and stored at 4${\pm}$1$^{\circ}C$ In the proximate composition, crude fat was slightly low in the T1 and T2(p<0.05). The pH and TBARS of the control were higher than those of the treatment groups(T1, T2). The pH, TBARS, VBN and WHC of all treatments significantly increased during storage period at 4 ${\pm}$ 1$^{\circ}C$(p<0.05). Oleic acid, palmitic acid, linoleic acid and stearic acid were major fatty acids in pork Linoleic acid and linolenic acid contents were higher in treatment groups than in the control.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.5
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• pp.31-39
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• 2007

This study was carried out to evaluation the recycled waste soils from construction site for planting soil. For this purpose, the concentrations of polluted materials and the physico-chemical properties were measured at recycled soil samples of an industrial waste treating company in the Metropolitan landfill area. The concentrations of polluted materials did not exceed to the standard critical levels of soil pollution in all analyzed items. The measures of the samples soil texture (loamy sand), bulk density (1.09~1.32g/$cm^3$), saturated hydraulic conductivity ($1.6{\times}10^{-3}{\sim}1.8{\times}10^{-3}$cm/sec), solid phase distribution (0.4~0.5$m^3/m^3$), porosity (0.5~0.6$m^3/m^3$), Ex. $K^+$ (1.0~1.2cmol/kg), Ex. $Mg^{2+}$ (0.2~0.6cmol/kg) were identified as not worse than those of conventional planting soil. But the sample soils have serious problems for planting soil such as high levels of pH (9.6~11.5), EC (0.78~1.84ds/m) and Ex. $Ca^{2+}$ (25.6~34.5cmol/kg), low level of organic matter (0.2~0.3%). It is required to improve pH, EC and Ex. $Ca^{2+}$ of sample soils. Consequently, the results suggested a high potential of recycling of the wastes soils for planting soil.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.3
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• pp.203-209
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• 2012

In this study, rheological properties of kaolinite and three different porcelain fluid muds are quantitatively estimated with the latest rheometer, in which variations of their viscosities and yield stresses with their densities are estimated. This study also involves the measurements for the basic physico-chemical properties of fluid muds and the qualitative analysis of their correlation between physico-chemical and rheological properties. Experimental results of rheological tests show that fluid muds in general belong to Pseudo-plastic fluids and both viscosities and yield stresses of them increase exponentially with the increase of density while they are remarkably different in quantity depending on sediments.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.548-553
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• 2004

Patties were prepared using Barbari male goats meat (age about 4 yrs) and packed in HDPE under vacuum (VP) and aerobically (AP). Packed patties were stored at 4$\pm$1$^{\circ}C$ and evaluated for physico-chemical, microbiological and sensory changes on days 0, 5, 10, 15, 20 and 25. Overall mean water activity ($a_{w}$), moisture (%), fat (%), pH, TBA number and W-B shear force values (kg/$cm^{2}$) of patties were 0.983, 61.93, 18.39, 6.38, 0.150 and 0.86, respectively. Except pH that was significantly higher and TBA number significantly lower in VP patties, treatment had no significant (p>0.05) effect on other physico-chemical traits. However, storage period significantly (p<0.05) affected physico-chemical traits. Moisture (63.79%) and $a_{w}$ (0.985) were significantly (p<0.05) higher on day 25. Patties became firmer on day 20 onwards as indicated by higher W-B shear force. Though packaging method had no significant effect, storage period influenced microbial counts. The standard plate counts (SPC), which were initially log 5.98 CFU/g decreased significantly (p<0.05) on day 10 followed by steady increase and reaching log 4.89 on day 25. Almost similar trend was observed for psychrotrophic bacteria counts. Lactic acid bacteria counts declined as the storage period progressed. Coliforms, and yeast and mould counts were either not detected by the method used or were very low in numbers. All samples of AP patties revealed swollen, greasy and sticky surface with spongy texture on day 20 whereas only some of the VP patties shown such changes on day 20. Results indicated that vacuum packaging had definite advantage in preserving the sensory quality of patties than aerobic packaging but it did not help in extending the shelf-life beyond 15 days.