• Journal of Environmental Impact Assessment
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• v.13 no.4
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• pp.197-211
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• 2004

Visibility impairment was known as an indicator of the increased air pollution. In many previous studies, it is known that both directly emitted fine particles mainly from vehicles and secondary aerosols from photochemical reactions could contribute to this visibility impairment in addition to the meteorological condition. Furthermore, the visibility showed different change patterns according to the geographical condition. In order to research into the influence of these factors on visibility, this study analyzed the visibility at 15:00, observed from 1990 to 2001 in Seoul, Ganghwa, Susan, Gwangju, Jeju. As a result, the visibility was increased in Seoul except the rainfall period, but in Susan, Gwangju, Jeju, it decreased with the relative humidity (RH). Especially, in Seoul, the number of low visibility days was larger than other sites and variations of the visibility were sensitive to the concentration of air pollutants, such as TSP, $NO_2$, $O_3$. The visibility impairment was mainly observed in meteorological condition of RH<50% and relatively stationary front. Therefore it is inferred that photochemical smog could lead to the low visibility in Seoul. On the other hands, in Ganghwa and Susan, when RH was 60~70%, the low visibility observed under the influence of the transports of air pollutants from nearby cities as well as humid air mass from coastal region. And in Jeju, sea fog and humid air mass caused the visibility impairment when the RH was larger than 80%. Finally, during the observational period, some cases of low visibility phenomena were simultaneously observed in the vast region including Seoul, Susan, Ganghwa. It not only includes the visibility aggravation by Asian Dust, but also could be caused by the movement and diffusion of flying dust or secondary aerosols. Moreover, the result shows that these phenomena could be mainly influenced by meteorological factors covering the wide regions.

• Korean Journal of Materials Research
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• v.30 no.6
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• pp.279-284
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• 2020

In this work, a carbon-doped carbon nitride photocatalyst is successfully synthesized through a simple centrifugal spinning method after heat treatment. The morphology and properties of the prepared photo catalyst are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis spectrophotometer (UV-vis), and specific surface area. The results show that the band gap of the prepared sample, g-CN-10 is 2.1 eV, is significantly lower than that of pure carbon nitride, 2.7 eV. As the amount of cotton candy increased, the absorption capacity of the prepared catalyst for visible light is significantly enhanced. In addition, the degradation efficiency of Rhodamine B (RhB) by sample g-CN-10 is 98.8 % over 2 h, which is twice that value of pure carbon nitride. The enhancement of photocatalytic ability is attributed to the increase of specific surface area after the carbon doping modifies carbon nitride. A possible photocatalytic degradation mechanism of carbon-doped carbon nitride is also suggested.

• Journal of Environmental Health Sciences
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• v.30 no.5 s.81
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• pp.358-365
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• 2004

The photocatalytic oxidation of Rhodamine B(RhB) was studied using photocatalytic reactor filled with module of quartz tube. Module of quartz tube consisted of small quartz tube (inner diameter, 1.5 mm; outer diameter, 3 mm) bundle coated with powder $TiO_2$ and uncoated large quartz tube (inner diameter, 20 mm; outer diameter, 22 mm). Two 30 W germicidal lamp was used as the light source and the reactor volume was 0.5 l. The effects of parameters such as the coating materials and numbers, initial concentration, $H_{2}O_2$ dose and metal deposition (Ag, Pt and Fe) and simultaneous application of $H_{2}O_2$ and metal deposition. The results showed that the initial reaction constant of quartz module coated with powder $TiO_2$ was higher 1.4 time than that of the $TiO_2$ sol and optimum coating number is twice. In order to increase reaction rate, simultaneous application of photocatalytic and photo-fenton reaction using Fe coating and dose $H_{2}O_2$ dose increased reaction rate largely.

• Fashion & Textile Research Journal
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• v.3 no.3
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• pp.271-276
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• 2001

In this study, We endeavored to revaluate the effects of different types of clothing and colors on clothing microclimate in the subjects wearing sports wear at sunlight environment. This study was conducted 4 different kinds (cotton 100%) of clothing ensembles, that was W-1(long trousers and shirt of white color), B-1 (long trousers and shirt of black color), W-s (short trousers and shirt white color), B-s (short trousers and shirt black color) and were done in a climate chamber under sunlight ambient temperature ($33.67{\pm}1.8^{\circ}C$, $46.0{\pm}8.5%RH$) by three males subject who are in good healthy. Start a 20-min rest period, 20-min bouts of exercise and final 20-min recovery period were performed. The kinetic load was given for 20 minutes under the condition of 6.0 km/hr walking speed on the treadmill. The results is as followed In case of same type of garment, temperature within clothing which is based on difference of color the white ensemble keeps higher temperature than black one. According to distribution chart of temperature within clothing in case of chest, white one shows higher temperature than black one, in case of back, black one shows higher temperature than white one. Difference of heart rate was so clear and sequence is W-1>B-1>W-s>B-s, so we could find same tendency with temperature within clothing.

• Food Science and Preservation
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• v.25 no.1
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• pp.62-70
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• 2018

This study investigates, the physicochemical characteristics of Sengmaksan (SM) prepared with Liriope platyphylla (LP) that had been roasted for different times (0, 30, 60, and 90 min, denoted as S-0, S-30, S-60, and S-90, respectively) The Hunter's color values such as lightness (L), redness (a), and yellowness (b) were the highest in S-0, while the lowest was found in S-90. The amount of soluble solid and reducing sugar content of S-60 were higher than the others. None of the samples exhibit significant differences in, their pH and acidity. The total content of phenolic compounds increased with the LP roasting time, but the total flavonoid and total anthocyanin contents of the SM decreased at the same time. The total ginsenoside (Ro, Rb2, Re, Rf, Rg1, Rg2, Rg3, Rh1, and Rh2) content did not show significant differences. The DPPH and ABTS radical scavenging activities increased according to the concentration, as well as with the LP roasting time. The ferric reducing antioxidant power (FRAP) showed trends similar to the radical scavenging activity, but it was more sensitive to the LP roasting time. From these results, the active ingredient in S-60 was higher, and the antioxidant activities of SM increased along with the roasting time of LP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.398-402
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• 1989

Moisture sorption and cooking properties of two varieties of Korean soybean(Jangyup and Whangkeum) were studied. When soybean was stored under the various relative humidities (RH) of 33-86% at 16'E for 125hours, its sorption behaviors were divided into two : desorption at the RHs of 33 and 44% and adsorption at the RHs of above 55%. The sorption rate was decreased rapidly during storage. In comparisons with only storage humidities, the sample stored at higher RH held the higher sorption rate. The relationships between storage time and sorption rate were applied well to the equation, log dw/dt= b log t+ log a, where w is the moisture content(%, db), t is time(hour) and a and b are the parameters which were calculated from the experimental data. The calculated moisture contents from the equation agreed well with the measured moisture contents. On the other hand, the cooking degrees of soybean which was steamed in an autoclave at $106-121^{\circ}C$ were compared by the maximum cutting forces. The cooking time to attain the same degree of cooking decreased logarithmically as the cooking temperature increased. The z-values which were calculated from the time-temperature combinations that gave the same degree of cooking for Jangyup and Whangkeum were $13.3^{\circ}C$ and $12.8^{\circ}C$ respectively.

• Molecules and Cells
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• v.21 no.1
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• pp.52-62
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• 2006

In previous reports we demonstrated that ginsenosides, active ingredients of Panax ginseng, affect some subsets of voltage-dependent $Ca^{2+}$ channels in neuronal cells expressed in Xenopus laevis oocytes. However, the major component(s) of ginseng that affect cloned $Ca^{2+}$ channel subtypes such as ${\alpha}_{1C}$(L)-, ${\alpha}_{1B}$(N)-, ${\alpha}_{1A}$(P/Q)-, ${\alpha}_{1E}$(R)- and ${\alpha}_{1G}$(T) have not been identified. Here, we used the two-microelectrode voltage clamp technique to characterize the effects of ginsenosides and ginsenoside metabolites on $Ba^{2+}$ currents ($I_{Ba}$) in Xenopus oocytes expressing five different $Ca^{2+}$ channel subtypes. Exposure to ginseng total saponins (GTS) induced voltage-dependent, dose-dependent and reversible inhibition of the five channel subtypes, with particularly strong inhibition of the ${\alpha}_{1G}$-type. Of the various ginsenosides, $Rb_1$, Rc, Re, Rf, $Rg_1$, $Rg_3$, and $Rh_2$, ginsenoside $Rg_3$ also inhibited all five channel subtypes and ginsenoside $Rh_2$ had most effect on the ${\alpha}_{1C}$- and ${\alpha}_{1E}$-type $Ca^{2+}$ channels. Compound K (CK), a protopanaxadiol ginsenoside metabolite, strongly inhibited only the ${\alpha}_{1G}$-type of $Ca^{2+}$ channel, whereas M4, a protopanaxatriol ginsenoside metabolite, had almost no effect on any of the channels. $Rg_3$, $Rh_2$, and CK shifted the steady-state activation curves but not the inactivation curves in the depolarizing direction in the ${\alpha}_{1B}$- and ${\alpha}_{1A}$-types. These results reveal that $Rg_3$, $Rh_2$ and CK are the major inhibitors of $Ca^{2+}$ channels in Panax ginseng, and that they show some $Ca^{2+}$ channel selectivity.

• Laboratory Medicine Online
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• v.7 no.4
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• pp.163-169
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• 2017

Background: An automated immunohematology analyzer, DAYMATE M (DAY Medical, Switzerland), has been recently developed. The potential of this analyzer to improve test results has been evaluated. Methods: A total of 300 blood samples from Seoul St. Mary's hospital and Incheon St. Mary's hospital were tested for ABO and RhD typing. In addition, 336 antibody screening test (AST) samples and 82 patients treated with hematopoietic stem cell transplantation (HSCT) were included. AST results by DAYMATE M were compared with those obtained by a manual method using DS-Screening II (Bio-Rad Laboratories, Switzerland) and red blood cells from Selectogen (Ortho-Clinical diagnostics Inc., USA). Results: Of the 300 patients enrolled, 87, 73, 79, and 61 had type A, B, O, and AB blood, respectively. The concordance rate was 99.9% for cell typing and 97.0% for serum typing. One discordant case was classified as type B instead of AB, and six discordant serum-typing cases were type A, but classified as type AB. Among the 336 AST samples, the concordance rate was 93.2%. From 136 positive cases, six were discordant. Within the 82 HSCT-treated patients, the concordance rate for ABO blood typing was 92.2%. Among the six discordant cases, DAYMATE M typed four cases as donor type where the standard method typed them as the recipient blood type. Conclusions: The DAYMATE M automated immunohematology analyzer performs reliably for ABO and RhD typing, as well as for ASTs and on samples from patients treated with HSCT.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.2910-2916
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• 2012

Cadmium sulphide (CdS) nanorods were prepared by a single precursor thermal decomposition (SPTD) method. The formation of CdS nanorods and their structure, morphology and elemental composition were studied by means of FT-IR, XRD, FE-SEM, HR-TEM and EDAX analysis. Photoluminescence (PL) and lifetime measurements were recorded to study the luminescence properties of the material. The PL spectrum of the CdS nanorods showed one broad peak and four shoulders and the cause for this emission was discussed. The PL emissions from the band edge and deep trap state of the CdS nanorods were studied by lifetime measurements. Further, the synthesized CdS nanorods showed an increase in efficiency of photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB). The increase in the photocatalytic activity was attributed to the mixed phase of the CdS nanorods.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.2
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• pp.103-109
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• 2013

In this study, the three sounds effects on subjects due to EEG type, and it researched to find optimal sound to increase their amenity and productivity. EEG and HRV were compared and analyzed in the environmental test room by classifying subjects into two type: A and B. The condition of the environmental test room was in temperature $31[^{\circ}C]$, relative humidity 50[RH%], air current speed 0.02[m/s] and illuminance 1000[lux] with setting up three different sounds which are U type sound, V type sound and Z type sound. The result of this study, at U type sound for A and B type, relative $M{\alpha}$ wave, relative $M{\beta}$ wave and SEF50 were revitalized. Also at Z type sound for A and B type, stress index, fatigue degree and HRT were decreased and SDNN was revitalized. Therefore U type sound is very effective to increase amenity, productivity and concentration, and Z type sound is very effective to decrease stress and fatigue degree.