• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.6
• /
• pp.834-840
• /
• 2018

In this study, the characteristics of air pollutant emissions from ships' engines have been investigated by conducting E2 and E3 cycle mode tests. A engine 360Ps (Doosan L126TIH engine) and 400kW dynamometer Horiba-Schenck were utilized for engine tests. The FTIR analyzer and SPC were used to measure exhaust gas (NOx, SOx etc.) and PM (particulate matter), respectively. The results showed that the emissions of THC and CO produced from engine were increased with the increase of sulfur content in fuel oils at E2 and E3 cycle modes. The kinetic viscosity of the fuel increased as the sulfur content of the fuel increased, thereby the specific fuel oil consumption (SFC) of the engine improved. This result is considered to be due to improved combustion conditions due to increased average diameters of sprayed particles and due to increased kinetic viscosity under constant fuel injection pressure in this study. In the case of NOx emission, this study showed no significant change in amount of sulfur content.

• Korean journal of food and cookery science
• /
• v.21 no.1 s.85
• /
• pp.117-123
• /
• 2005

Washed rice was coated by spraying aqueous dandelion (Taraxacum officinale) extracts at 20, 30, 40 $^{\circ}$Brix and dried at room temperature. The coating procedure was conducted 5 mL/min for 10min. Property changes in the dandelion coated rice and un-coated cooked rice were observed during 2 days of storage. Increasing the coating concentration was associated with lower color values (L, a value) and moisture contents. Sensory and texture properties generally decreased in the cooked rice coated with dandelion more than the control (non-coated rice). But, D-20(20 $^{\circ}$Brix of the dandelion concentration) resulted in better textural properties and sensory scores for hardness and overall acceptability in cooked rice. Compared to the control, the washed rice coated with 20 $^{\circ}$Brix for 0 and 2 days showed better quality in sensory activities, a lower gel consistency and better textural activities. It was concluded that the optimum coating ration of rice and added dandelion extract for cooking were 20 $^{\circ}$Brix and $5\%$ respectively, in proportion to the total weight of raw rice.

• Journal of the Korea Concrete Institute
• /
• v.25 no.6
• /
• pp.621-630
• /
• 2013

Several techniques for steel corrosion detection are proposed and HCP (half cell potential) technique is widely adopted for field investigation. If concrete has cracks on surface, steel corrosion is rapidly accelerated due to additional intrusion of chloride and carbon dioxide ions. This study is for an evaluation of HCP in cracked concrete exposed chloride attack. For this work, RC (reinforced concrete) beams are prepared considering 3 w/c ratios (0.35, 0.55, and 0.70) and several cover depths (10~60 mm) and various crack widths of 0.0~1.0 mm are induced. For 35 days, SST (salt spraying test) is performed for corrosion acceleration, and HCP and corrosion length of rebar are evaluated. With increasing crack width, w/c ratios, and decreasing cover depth, HCP measurements increase. HCP evaluation technique is proposed considering the effects of w/c ratios, crack width, and cover depth. Furthermore anti-corrosive cover depths are obtained through Life365 program and the results are compared with those from this study. The results shows relatively big difference in cracked concrete, however provide similar anti-corrosive conditions in sound concrete.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.5
• /
• pp.289-293
• /
• 1998

We investigated the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in methanol extracts of 64 cultured cell lines, which were derived from various plant species, and the ascorbate content in cell lines, which showed a high radical scavenging activity. Thirteen cell lines revealed the antioxidative activity ($IC_{50}$) by methanol extracts of less than 50 mg in cell fresh wt. Of them, six cell lines showed the same Rf value as ascorbate on the DPPH sprayed silica gel TLC. The ascorbate content in cell lines of Rosa multiflora, Scutellaria baicalensis, and Achyranthes japonica showed 48.5, 30.3, and $16.8\;\mu\textrm{g}$ per g cell fresh wt by HPLC analysis, respectively. In callus cultures of S. baicalensis, the concentration of ascorbate reached a maximun ($39{\pm}3.4\;\mu\textrm{g}/g$ cell fresh wt) on 30 days after subculture, which corresponded to the stationary growth phase, and subsequently decreased by successive culturing.

• Journal of the Korean Institute of Gas
• /
• v.19 no.4
• /
• pp.22-28
• /
• 2015

In order to keep the competitiveness of LPG fuel for transportation fuel, the difference in fuel consumption with gasoline and cost for an aftertreatment system should be reduced with continuous development of technology for LPG engine. In the present study, spray-guided type direct injection combustion system, whose configuration is composed of direct injector in the vicinity of spark plug, was employed to realize stable lean combustion. A certain level of nitrogen oxides($NO_x$) emits due to a locally rich mixture regions in the stratified mixture. With the application of EGR system for the reduction of $NO_x$, 15% of $NO_x$ reduction was achieved whereas fuel consumption and hydrocarbon emission increased. By the application of EGR, the combustion speed reduced especially appeared at initial flame development period and peak heat release rates and increasing rates for heat release rate decreased as EGR rate increased due to the dilution effect of intake air.

• Food Science of Animal Resources
• /
• v.30 no.1
• /
• pp.102-109
• /
• 2010

Imitated cheese was prepared from whole milk powder and fermented milk and the moisture content, general components, noncasein nitrogen, nonprotein nitrogen and free amino acids were analyzed to determine the optimal ripening conditions needed to produce imitated cheese that was similar to natural cheese. The moisture content of the imitated cheese was 40.27% one day after being produced. The cheese was ripened using two different methods; at $12^{\circ}C$ with vacuum sealing and at $12^{\circ}C$ and 95% RH with a spray of Penicillium camemberti. The lactose content decreased rapidly from 24.64 to 5.43% at the $4^{th}$ wk of ripening when it was ripened with Penicillium camemberti. The degradation of protein by mold ripening in the imitated cheese was more rapid than that of vacuum sealing. The flavor and body texture were optimal at the $4^{th}$ wk ripening. The noncasein nitrogen and nonprotein nitrogen content increased from 28.10 to 54.05, and from 6.58 to 23.06 mg/mL, respectively, when ripened with P. camemberti. When the cheese was ripened at $12^{\circ}C$, 95% R.H with P. camemberti after 4 wks, all free amino acids increased significantly except asparagines. The total free amino acid and bitter amino acid concentrations increased from 8.40 to 34.87, and from 1.53 to 10.02 nmol/mg, respectively. When the imitated cheese was prepared, the protein degradation and flavor of the cheese was better when ripened with P. camemberti.

• Applied Microscopy
• /
• v.39 no.1
• /
• pp.27-40
• /
• 2009

Acute respiratory distress syndrome (ARDS), also known as an acute inflammatory lung disease is developed by various factors that is originated from the destruction of alveolar-capillary barrier, and neutrophils plays an important role in the destruction. The study intended to confirm, the anti-inflammatory effect of germanium, whether a lung injury has been mitigated with the reduction of injury in alveolar-capillary barrier resulting from inhibition of neutrophils migration in lung tissue. Test groups were divided in saline administered CON, 5 hours of endotoxin administered LPS and 5 hours of endotoxin administered Ge+LPS following 1 hours of pre-processed germanium. $100{\mu}g$ endotoxin was melted in 0.5 mL saline and sprayed into airway and 26 mg germanium per 100 g weight was administered into abdominal cavity. The endotoxin group which induced an acute lung injury with administered endotoxin showed dramatic increase of pulmonary edema (p<0.001), protein contents in bronchoalveolar lavage fluid, BALF (p<0.05) and neutrophils of infiltration in BALF (p<0.001) comparing with a control group, while a pre-treated germanium group showed significant decrease in all categories comparing to the endotoxin administerd group. In the result of a microscopic observation, the structure of alveolar-capillary barrier which is constructed with basal lamina, alveolar type I cells and endothelial cell were preserved of the pre-treated germanium group relatively well compare to the endotoxin administered group. And the construction of lamellar body, microvilli and basal lamina of alveolar type II cells were also preserved relatively well. Hence, germanium activates as an anti-Inflammatory mediator in other words, it interfered neutrophils migration into lung tissue, thereby reduced injury of alveolar-capillary barrier from toxic substances of activated neutrophils. Consequently, the study has determined that the acute lung injury induced by endotoxin has been decreased by the pre-treated germanium.

• Korean Journal of Food Science and Technology
• /
• v.42 no.1
• /
• pp.103-108
• /
• 2010

To obtain the best yield of the beneficial ingredients in green tea, such as catechins, green tea powder is most often prepared by ethyl alcohol extraction. However, the taste, cost and composition of ethyl alcohol extract is different from aqueous spray-dried green tea extract (aq-GTE). Specifically, aq-GTE has a better flavor, lower production costs and higher purity when compared to ethyl alcohol extract. In this study, we elucidated the effect of aq-GTE on diet-induced obesity in male C57BL/6J mice following dose-dependent oral administration of aq-GTE. After eight weeks, the body weight was reduced by 13-17% in mice fed 200 mg/kg bw aq-GTE ($12.468{\pm}0.45\;g$; p<0.05) and 20-25% in mice fed 400 mg/kg bw aq-GTE ($11.259{\pm}0.61\;g$; p<0.05) when compared with the high-fat diet (HFD) control group mice ($14.714{\pm}0.95\;g$; p<0.05). The correlation between epididymal fat accumulation and body weight also decreased by approximately 26.6% (p<0.05) in mice fed a HFD with aq-GTE 400 mg/kg bw. Finally, serum parameters such as the triglyceride, glucose and cholesterol levels in the HFD groups were reduced by the aq-GTE 400 mg/kg bw diet. Analysis on glutamic-pyruvic transaminase, blood urea nitrogen and development of hepatic steatosis revealed no histologic evidence of hepatotoxicity in HFD mice fed aq-GTE. Overall, our results imply that aq-GTE is able to regulate body weight and fat accumulation in mice.

• Tuberculosis and Respiratory Diseases
• /
• v.48 no.2
• /
• pp.246-259
• /
• 2000

Background: As one of the etiologies of acute respiratory distress syndrome(ARDS), sepsis is one of the morbid causes of this cryptogenic malady. Even though many documents on the role of endotoxin(ETX) in the pathogenesis of ARDS have been issued, still the underlying mechanism associated with oxidative stress and activation of $PLA_2$ has been controversial. In the present study, the role of phospholipase $A_2(PLA_2)$ in the neutrophilic respiratory burst, which is presumed to cause acute lung injury during sepsis, was probed. Method: In glutathione-depleted Sprague-Dawley rats, lung leak, infiltration of neutrophils, $PLA_2$ activity and lipid peroxidation in the lung were measured after intratracheal instillation of endotoxin(delete). In addition, gamma glutamyl transferase(GGT) activity and the amount of pulmonary surfactant were measured. Morphologically, the changes in ultrastructure and cytochemical demonstration of oxidants were presented to confirm the neutrophilic oxidative stress and to elucidate the effects of $PLA_2$ activation on(delete) oxidative stress. Results: Instillation of ETX to glutathione-depleted rats intensified lung leak and lipid peroxidation when compared with non-glutathione depleted rats treated with the endotoxin. Moreover, oxidative stress was confirmed by the assay of GGT and malondialdehyde. Functionally, the depletion of glutathione altered the secretion of pulmonary surfactant from alveolar type II cells. Ultrastructurally and cytochemicaliy, oxidative stress was also confirmed after treatment of with ETX and diethylmaleate(DEM). Conclusion: The endotoxin-induced acute lung injury was mediated by oxidative stress, which in turn was provoked by the neutrophilic respiratory burst. The activation of $PLA_2$ in the lung seems to playa pivotal role in the oxidative stress of the lung.

• Korean Journal of Plant Resources
• /
• v.36 no.5
• /
• pp.517-526
• /
• 2023

The harvest time of the late-ripening 'Fuji' apple (Malus × domestica) is variable, depending on the coloration of the fruit skin. Ethephon, a plant growth regulator, promotes the ethylene production and induces physiological responses associated with fruit maturation in climacteric fruit crops, such as apples. This study aimed to investigate the effect of ethephon treatment on fruit characteristics after fruit enlargement, with the objective of proposing an economical and stable harvest control method for 'Fuji'/M.26 apples. Fruit characteristics were assessed at 10-days intervals following the application of 100 mg/L ethephon and mixture of 100 mg/L ethephon and 0.5% CaCl₂ at 145 days after full bloom (DAFB). Starch contents of ethephon-treated (ET) and ethephon with CaCl₂-treated (EC) apples began to decrease from 155 DAFB, and the starch contents of ET and EC at 10 days before harvest were similar to those of control at harvest time. Red coloration of fruit skin in EC was lower compared to ET but higher than control. The average fruit firmness was low in ET, while the control and EC exhibited similar levels of firmness. Fruit sugar acid ratios did not show significant differences between treatments. However, the titratable acidity of EC was significantly lower than that of the control at 10 days before harvest. Moreover, fruit sugar acid ratio of ET and EC at 10 days before harvest in 2021 was similar to their sugar acid ratio at harvest time. Therefore, it was thought that fruit maturation and skin coloration could be accelerated by 10 days from the harvest time through the combined treatment of 100 mg/L ethephon and 0.5% CaCl₂ at the end of fruit enlargement in 'Fuji'/M.26.