• Journal of Electrochemical Science and Technology
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• v.10 no.4
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• pp.424-432
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• 2019

Planar BiVO₄ and 3 wt% Mo-doped BiVO₄ (abbreviated as Mo:BiVO₄) film were prepared by the facile spin-coating method on fluorine doped SnO₂(FTO) substrate in the same precursor solution including the Mo precursor in Mo:BiVO₄ film. After annealing at a high temperature of 450℃ for 30 min to improve crystallinity, the films exhibited the monoclinic crystalline phase and nanoporous architecture. Both films showed no remarkably discrepancy in crystalline or morphological properties. To investigate the effect of surface passivation exploring the Al₂O₃ layer, the ultra-thin Al₂O₃ layer with a thickness of approximately 2 nm was deposited on BiVO₄ film using the atomic layer deposition (ALD) method. No distinct morphological modification was observed for all prepared BiVO₄ and Mo:BiVO₄ films. Only slightly reduced nanopores were observed. Although both samples showed some reduction of light absorption in the visible wavelength after coating of Al₂O₃ layer, the Al₂O₃ coated BiVO₄ (Al₂O₃/BiVO₄) film exhibited enhanced photoelectrochemical performance in 0.5 M Na₂SO₄ solution (pH 6.5), having higher photocurrent density (0.91 mA/㎠ at 1.23 V vs. reversible hydrogen electrode (RHE), briefly abbreviated as V_RHE) than BiVO₄ film (0.12 mA/㎠ at 1.23 V_RHE). Moreover, Al₂O₃ coating on the Mo:BiVO₄ film exhibited more enhanced photocurrent density (1.5 mA/㎠ at 1.23 V_RHE) than the Mo:BiVO₄ film (0.86 mA/㎠ at 1.23 V_RHE). To examine the reasons, capacitance measurement and Mott-Schottky analysis were conducted, revealing that the significant degradation of capacitance value was observed in both BiVO₄ film and Al₂O₃/Mo:BiVO₄ film, probably due to degraded capacitance by surface passivation. Furthermore, the flat-band potential (V_FB) was negatively shifted to about 200 mV while the electronic conductivities were enhanced by Al₂O₃ coating in both samples, contributing to the advancement of PEC performance by ultra-thin Al₂O₃ layer.

• The Journal of Internal Korean Medicine
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• v.30 no.3
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• pp.558-570
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• 2009

Background : Since March 2009, when the first patient of novel influenza A (H1N1) was reported, many deaths have occurred in North and Central America. The start of the 2009 influenza pandemic was declared by WHO Director-General Dr. Margaret Chan on 11 June 2009, and the level of influenza pandemic alert raised from phase 5 to phase 6. There was no vaccine yet developed, and many experts worried that the novel H1N1 virus could kill as many or more as did the influenza pandemic in 1918-1919. Objective : To evaluate the possibility of treatment for 2009 novel influenza A (H1N1) using herbal remedies and other non-conventional therapies. Methods : We researched the clinical studies for novel H1N1 influenza virus-related herbal medicine or non-conventional medicine treatment using internet search engines including PubMed and CNKI. In addition, we reviewed many reports and clinical practice guidelines (CPG) for influenza A (H1N1). Results : Two case series were selected after reviewing 701 papers, and two CPG published by the Chinese government and Jilin province identified. They reported that the clinical symptoms were no more significant than seasonal influenza, and the condition of patients more than 45 years old was milder than those less than 45 years old. There are no patients with gastric problems, and oseltamivir has been used at the same time in all patients. Conclusion : The efficacy and effectiveness of herbal medicine and other non-conventional treatments for the novel influenza A (H1N1) is questionable, and more studies are needed to draw a firm conclusion. However, in the severe acute respiratory syndrome (SARS) experience in 2002/2003, it was demonstrated that herbal medicine can relieve all symptoms of SARS patients, promote absorption of lung inflammation, improve the degree of blood oxygen saturation, regulate immunological functions, reduce the required dosage of glucocorticoid and other medicines, and reduce case fatality rate. In light of the current situation that there is no vaccine or conventional treatment yet available, the study of herbal medicine and other non-conventional therapies are also necessary for appropriate evaluation.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.91-101
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• 2011

The purpose of this study is to demonstrate the positive effects of artificial ground greening on the reduction of carbon dioxide ($CO_2$) which can help improve ecological functions in cities and mitigation of climate change, through quantifying $CO_2$ uptake and evapotranspiration by the process of photosynthesis of some plants. Experiment of $CO_2$ uptake and evapotranspiration was conducted by measurement of $CO_2$ exchange rate using the infrared gas analyzer, for 7 month, growing season from May to November 2009, 2 times a month. The result was as follows; The $CO_2$ uptake quantity per $cm^2$ of Chrysanthemum zawadskii was the highest rate at $21.47{\times}10^{-6}g/cm^2/s$ and Poa pratensis was $16.20g{\times}10^{-6}g/cm^2/s$. The stronger was light of intensity, the higher were $CO_2$ uptake rate of most plants. In quantity of evapotranspiration, Poa pratensis was the highest rate at $8.75{\times}10^{-5}g/cm^2/s$ and Aquilegia buergariana was $8.66{\times}10^{-5}g/cm^2/s$. From this study, it is confirmed that artificial ground greening has capacity of absorption $CO_2$ and effects on improving urban microclimate.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1285-1290
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• 2017

We prepared ITZO thin films with various thicknesses on glass substrates using RF magnetron sputtering and investigated electrical, optical and structural properties of the thin film. Sheet resistance of ITZO thin film showed a decreasing trend on the increase of film thickness, but its resistivity exhibited a substantially constant value of $5.06{\pm}1.23{\times}10^{-4}{\Omega}-cm$. Transmittance of ITZO thin film moved to the long-wavelength with the increase of film thickness. Figure of merit in a visible light and an absorption area of P3HT:PCBM organic active layer of the 360nm-thick IZTO thin film was $8.21{\times}10^{-3}{\Omega}^{-1}$ and $9.29{\times}10^{-3}{\Omega}^{-1}$, respectively. Through XRD and AFM measurements, it was confirmed that all the ITZO thin films have amorphous structure and the surface roughness of films are very smooth in the range of 0.561 to 0.263 nm. In this study, it was found that amorphous ITZO thin film is a very promising material for organic solar cell.

• Resources Recycling
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• v.20 no.1
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• pp.54-60
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• 2011

The spherical artificial aggregates (AAs) with a diameter of 8 mm, which contains fly ashes discharged from the fluidized bed combustion in a thermal power plant and clay were manufactured by direct sintering method at $1050{\sim}1250^{\circ}C$ for 10 minutes. The effect of fly ash contents on the bloating phenomenon in the AAs was analyzed. The AAs containing fly ash of the amount under 50 wt% showed the black-coring and bloating phenomena. The AAs containing fly ash of the amount over 5Owt%, however, the specific gravity was increased and the color of specimens fully changed to black. These color change phenomena were caused from the formation of FeO by the reduction reaction of almost $Fe_2O_3$ component by the excessive reducing atmosphere formed simultaneously with the rapid emission of the gases generated from the high contents of unburned carbon of with increasing the added fly ash amount. Specific gravity was decreased as fly ash contents increased in the case of sintering at the same temperature condition. Water absorption of all specimens except of the specimens containing 10 wt% fly ashes decreased with increasing sintering temperature. These were because a liquid phase was formed as the increasing the sintering temperature. In the case of the specimens manufactured in this study containing fly ashes discharged from the fluidized bed combustor in a the thermal power plant and 10~90 wt% of clay, the specific gravity was 0.9~1.8 and the water absorptivity was 8~60%, therefore it is considered that those results can be applied to the light or heavy aggregates.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.27-33
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• 1987

The environment and biological studies of tritium have been carried out in the advanced countries since the mid 1950's. In the case of a potential tritium exposure, the usual procedure is trifium bioassay (as HTO) in human urine in order to determine the amount of tritium deposited in the body called tritium body burden. The maximum permissible body burden(MPBB) of tritium in total body is about $30{\mu}Ci/{\ell}$ for body tissue. In the bioassay, the most common investigation level for detection of tritium in urine is 1/10th of MPBB. For this bioassay project, the first priority is given to obtaining a quench correction curve. This consideration is necessary because of the variability in color of human urine specimens. Quenching effect in this case mainly is caused by the absorption of scintillation light flashes by the urine sample. By the least squares method on the statistical basis, an estimated formula for quench correction curve was determined to be Y = 0.771 + 1.836 ${\tmes}10^{-4}$X, where the efficiency(Y) was ranged from about 12% to 31% in the liquid scientillation counting. In this paper, a brief theory concerning the biological half-life of tritium and the retention formula to apply to systematically distributed tritium are described.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.47-54
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• 2010

This study is progressed function ratio, it's trued taste by an experiment to present data for human work light weight aggregate development that use clink ash progressed liquid limit, small success limit, wear loss in quantity, sand equivalent, sieve cutting examination. 80:20's match of function rain examination is 1.4, and that use rubble aggregate as recyeled-panit lightweight aggregate's capacity ratio increases by 1.0 increase of function rain many. Also, examination multiplied delicate flavor gradually according to increase of the mixing rate, and absorption coefficient increased. This is judged by phenomenon that appear by special quality upper recycled-panit of polystyrene bid and porosity's increase between lightweight aggregate. It is case that use aggregate of wear loss in quantity is 13.5 in sand equivalent and a wear loss in quantity experiment and although case that mix 20% increases by 14.4, this phenomenon by weak tissue of lightweight aggergate be judged. When it's as a these experiment, the statue prevention floor of a street improvement specifications is prescribing so that satisfy by sand equivalent 20, CBR 10. This is showed result that this satisfies in quality standard all in match experiment ago that see.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.1
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• pp.15-18
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• 2009

To enhance near UV-visible absorption region and to applied phosphor convert-white LEOs (PC-WLEDs), a red phosphor composed of ${Y_2}{SiO_5}:\;EU^{3+}$, $Bi^{3+}$ compounds was prepared by the conventional solid-state reaction. The photoluminescence (PL) shown that samples were excited by near UV light 395 nm for measurement of PL spectra. Emission spectra of samples have shown red emissions at 612 nm ($^5D_0{\to}^7F_2$). The enhanced near $UV{\sim}$ visible excitation spectrum with a broad band centered at 258 nm and 282 nm originated in the transitions toward the charge transfer state (CTS) due to the $Eu^{3+}-Bi^{3+}-O^{2-}$ interaction. The other excitation band at $350\;nm{\sim}480\;nm$, corresponding to the transitions $^7F_0{\to}^5L_9$ (364 nm), $^7F_0{\to}^5G_3$ (381 nm), $^7F_0{\to}^5L_6$ (395 nm), $^7F_0{\to}^5D_3$, (415 nm) and $^7F_0{\to}^5D_2$ (466 nm), occurred due to enhanced the f-f transition increasing $Bi^{3+}$ and $Eu^{3+}$ ions. The PL intensity increased with increased as concentration of $Bi^{3+}$ and the emission intensity becomes with a maximum at 0.125 mol.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.5
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• pp.386-392
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• 2001

Quality characteristics of conventional and whey noodles were investigated by studying the textural properties. cooking properties, and sensory characteristics. The whey noodles were prepared by mixing whey powder with the wheat flour before noodle production, with the mixture ratio ranging between 1 and 7% in volume. The results are summarized as follows : the addition of whey powder noticeably improved the textural characteristics of the cooked noodles, i.e. hardness, gumminess, and chewiness. The best results were obtained using the following percentage of whey in the mixture: the hardness with 1% added, the gumminess and chewiness with 3% added, and the elasticity with a 7% addiction. The tension force also increased with addition of whey powder, The highest tension force was obtained when 3% of the whey was mixed. While the cooking water of the general noodles displayed a light reddish tint, the cooking water of the whey noodles had a yellow-greenish tint. The cooking water of the whey noodles was more turbid than that of the conventional noodles. The whey noodles increased in volume more than the conventional noodles. after cooking. There was no difference in weight increase and water absorption rates between both types of noodles. More favorable results were shown for appearance, color, texture, and sensory acceptability in the whey noodle than in the conventional noodles.

• Clean Technology
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• v.26 no.1
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• pp.7-12
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• 2020

Ti-SBA-15 catalysts doped with lanthanide ions (Ln/Ti-SBA-15) were successfully synthesized using conventional hydrothermal method. In addition, they were characterized by XRD, FT-IR, DRS, BET, and PL. The activity of these materials on the photocatalytic decomposition of methylene blue under ultraviolet light irradiation was also examined. Ti-SBA-15 catalysts doped with various lanthanide ions maintained their mesoporous structure. The pore size and pore volume of Ln/Ti-SBA-15 materials decreased but their surface area increased upon the doping of lanthanide ion. Ln/Ti-SBA-15 materials exhibited the type IV nitrogen isotherm with desorption hysteresis loop type H2, which was characteristic of mesoporous materials. The size of hysteresis increased in the doping of lanthanide ions on Ti-SBA-15 material. There was no absorption in the visible region (> 400 nm) regardless of the doping of lanthanide ions to TiO₂ particles, while the broad bands at 220 nm appeared at the Ln/Ti-SBA-15 samples, indicating the framework incorporation of titanium into SBA-15. 1 mol% Pr/ Ti-SBA-15 catalysts showed the highest photocatalytic activity on the decomposition of methylene blue but the Ti-SBA-15 catalysts doped with Eu, Er, and Nd ions showed lower activity compared to pure Ti-SBA-15 catalyst. The PL peaks appeared at about 410 nm at all catalysts while the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of methylene blue.