• Journal of Korean Society on Water Environment
• /
• v.29 no.2
• /
• pp.239-246
• /
• 2013

The foot and mouth disease and AI were highly contagious. The virus can be transmitted in a number of ways, including close-contact animal to animal spread, long-distance aerosol spread and fomites, or inanimate objects, typically fodder and motor vehicles. A lot of burial sites were constructed in a short time for preventing the rapid spread of the virus. The carcass burial sites have a risk potential because the sites were constructed without any appropriate and systematic management. It resulted from lacking of time, equipments and man power. The carcass burial sites more than 4,700 constructed in 2011. Approximately 7 million poultry and 3.5 million livestock including head of cattle and swine were buried in farm land. It is time to be concerned if the secondary pollutions occur from the burial sites. The environmental impacts should be analyzed for managing the burial sites effectively and minimizing damages and risks to the environment and human health. This study was to analyze environmental impacts of the process of carcass burial construction using a life cycle assessment methodology. All input data of raw materials and energy usage were collected and the inventory was constructed. The results showed that 1 ton of carcass burial of the environmental impacts were $0.51yr^{-1}$ for ADP, 0.09 kg of 1,4DCB-eq for FAETP, 31.17 kg of $CO_2-eq$ for GWP, 0.04 kg of $C_2H_4-eq$ for POCP, 0.06 kg of $SO_2-eq$ for AP.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.1234-1238
• /
• 2005

우리나라의 수질오염에 대한 규제는 주로 호소 및 하천의 수질을 향상시키기 위하여 하수 및 공장폐수 등 점오염원을 중심으로 관리되어 왔으나 강우와 함께 대량 유출된 비점오염원은 수용하천의 자정능력을 감소시키고 있고 이로 인해 하천과 호소의 수질은 향상되지 못하고 있다. 또한, 농촌지역에서 배출되는 비점오염원은 정확한 기작의 분석이 안 되고 있으며, 비료$\cdot$농약의 사용 증가에 따라 영양염 및 유해물질에 의한 수질오염의 영향이 증가되고 있는 실정이다. 본 연구는 농촌지역의 강우-유출로 인한 비점오염물질의 유출특성 및 배출부하량을 조사하기 위하여 영산강권역의 외남천을 대상으로 조사하였다. 대상 유역의 토지용도 구분은 (1)논지역, (2)밭지역, (3)산지지역, (4)농촌주거지역, (5)복합지역(논, 산지)으로 구분하였다. 시료의 채취는 강우시 5회에 걸쳐 조사하였으며, 2L 용량의 무균채수병에 채취한 후, 아이스박스에 $4^{\circ}C$이하로 보관하여 24시간 이내로 실험실에 운반하여 실험하였으며, 매회 시료 채취 주기는 강우유출이 발생하기 전부터 강우 종료 후 유출량 변화가 없을 때까지 $9\~12$단계로 세분하여 유출량과 pH, DO, BOD, COD, SS, T-N, T-P의 농도를 측정하였다. 본 연구에서 조사한 결과 토지이용별 비점오염원의 SMC를 살펴보면 BOD의 SMC는 $4.38\~11.02mg/{\ell}$, COD의 SMC는 $7.07\~23.99mg/{\ell}$, T-N은 $1.57\~5.20mg/{\ell}$, T-P는 $0.11\~0.274mg/{\ell}$의 범위를 갖는 것으로 나타났으며, 전반적으로 논 지역에서 비교적 높게 나타났는데 이는 농작물의 경작에 따른 시비법의 영향으로 판단된다. 또한, 비점오염원의 유출특성을 보면 전반적으로 초기 오염물질 유출특성 갖는 것으로 나타났다.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2006.05a
• /
• pp.583-587
• /
• 2006

국부세굴의 발생은 일반적으로 흐름조건, 구조물 조건과 하상재료 세 가지의 주 원인으로 구분할 수 있다. 흐름조건의 경우 구조물 영향으로 발생되는 3차원적인 와류가 주요원인이며 하상재료의 경우 여러 요인이 있겠지만 비중이 같은 입자라 가정할 경우 입자의 크기를 주요 변수로 정할 수 있다. 교각 국부세굴에 관한 연구는 1960년대 이후 연구자들에 의해 매우 다양하게 수행되어 졌으며 많은 산정공식도 제시되었다. 하지만 기존 연구는 최대세굴심 조건으로 다양한 하상재료와 시간에 대한 세굴변동(홍수사상 등)에 대한 영향을 고려하는데 어려움이 있다. 특히 국내의 경우 다양한 하상재료와 홍수빈도를 고려할 때 이에 대한 세굴적용은 매우 중요한 인자라 할 수 있다. 따라서 교각세굴에 대한 궁극적인 목적은 다양한 하상재료와 홍수빈도를 고려할 수 있는 세굴평가를 제안하는데 있다. 이를 위해 본 연구에서는 우선적인 연구로 입자의 다양성과 이미지 기법을 이용한 실시간 측정을 통해 보완하여 입자에 따른 시간적 변화를 분석하였다. 현재 4가지의 하상재료의 입경차이에 따른 국부세굴의 시간적 변화와 초기세굴 발생의 수리적 조건을 파악하고 기존연구와 비교분석하였으며, 이를 기초자료로 세굴심$(S,\;S_{max})$, 교량주변 전단력$({\tau}_p,\;{\tau}_{pc})$, 접근수로부 전단력$({\tau}_a)$와 입자한계전단력$({\tau}_c)$에 대한 시간분석 (time effect)을 통해 다양한 하상재료와 홍수빈도를 해석을 위한 초기분석을 수행하는데 목적이 있다. 수리모형실험에 사용된 가변경사수로의 제원은 $0.6m(W){\times}20m(L){\times}2m(H)$이며 모형구조물은 투명한 아크릴로 제작하였다. 실험방법은 교각 내부에 CC카메라를 전 후면 및 상측면에 설치하여 세굴 발생을 실시간으로 촬영한 후 이미지 분석을 통해 분석하였다.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2011.10a
• /
• pp.16.2-16.2
• /
• 2011

Graphene has attracted significant attention due to its unique characteristics and promising nanoelectronic device applications. For practical device applications, it is essential to synthesize high-quality and large-area graphene films. Graphene has been synthesized by eloborated mechanical exfoliation of highly oriented pyrolytic graphite, chemical reduction of exfoliated grahene oxide, thermal decomposition of silicon carbide, and chemical vapor deposition (CVD) on metal substrates such as Ni, Cu, Ru etc. The CVD has advantages over some of other methods in terms of mass production on large-areas substrates and it can be easily separated from the metal substrate and transferred to other desired substrates. Especially, plasma-enhanced CVD (PECVD) can be very efficient to synthesize high-quality graphene. Little information is available on the synthesis of graphene by PECVD even though PECVD has been demonstrated to be successful in synthesizing various carbon nanostructures such as carbon nanotubes and nanosheets. In this study, we synthesized graphene on $Ni/SiO_2/Si$ and Cu plate substrates with CH4 diluted in $Ar/H_2$ (10%) by using an inductively-coupled PECVD (ICPCVD). High-quality graphene was synthesized at as low as $700^{\circ}C$ with 600 W of plasma power while graphene layer was not formed without plasma. The growth rate of graphene was so fast that graphene films fully covered on substrate surface just for few seconds $CH_4$ gas supply. The transferred graphene films on glass substrates has a transmittance at 550 nm is higher 94%, indicating 1~3 monolayers of graphene were formed. FETs based on the grapheme films transferred to $Si/SiO_2$ substrates revealed a p-type. We will further discuss the synthesis of graphene and doped graphene by ICPVCD and their characteristics.

• Korean Journal of Materials Research
• /
• v.24 no.6
• /
• pp.285-292
• /
• 2014

Commercial activated-carbon used as the electrode material of an electric double-layer capacitor (EDLC) was posttreated with various acids and alkalis to increase its capacitance. The carbon samples prepared were then heat-treated in order to control the amount of acidic functional groups formed by the acid treatments. Coin-type EDLC cells with two symmetric carbon electrodes were assembled using the prepared carbon materials and an organic electrolyte. The electrochemical performance of the EDLC was measured by galvanostatic charge-discharge, cyclic voltammetry, and electrochemical impedance spectroscopy. Among the various activated carbons, the carbon electrodes (CSsb800) prepared by the treatments of coconutshell-based carbon activated with NaOH and $H_3BO_5$, and then heat treated at $800^{\circ}C$ under a flow of nitrogen gas, showed relatively good electrochemical performance. Although the specific-surface-area of the carbon-electrode material ($1,096m^2/g$) was less than that of pristine activated-carbon ($1,122m^2/g$), the meso-pore volume increased after the combined chemical and heat treatments. The specific capacitance of the EDLC increased from 59.6 to 74.8 F/g (26%) after those post treatments. The equivalent series resistance of EDLC using CSsb800 as electrode was much lower than that of EDLC using pristine activated carbon. Therefore, CSsb800 exhibited superior electrochemical performance at high scan rates due to its low internal resistance.

• Korean Journal of Materials Research
• /
• v.26 no.12
• /
• pp.681-687
• /
• 2016

Zirconium(Zr) nuclear fuel cladding tubes are made using a three-time pilgering and annealing process. In order to remove the oxidized layer and impurities on the surface of the tube, a pickling process is required. Zr is dissolved in HF and $HNO_3$ mixed acid during the process and pickling waste acid, including dissolved Zr, is totally discarded after being neutralized. In this study, the waste acid was recycled by adding $BaF_2$, which reacted with the Zr ion involved in the waste acid; $Ba_2ZrF_8$ was subsequently precipitated due to its low solubility in water. It is very difficult to extract zirconium from the as-recovered $Ba_2ZrF_8$ because its melting temperature is $1031^{\circ}C$. Hence, we tried to recover Zr using an electrowinning process with a low temperature molten salt compound that was fabricated by adding $ZrF_4$ to $Ba_2ZrF_8$ to decrease the melting point. Change of the Zr redox potential was observed using cyclic voltammetry; the voltage change of the cell was observed by polarization and chronopotentiometry. The structure of the electrodeposited Zr was analyzed and the electrodeposition characteristics were also evaluated.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.7
• /
• pp.931-936
• /
• 2010

This experiment was conducted to evaluate the bioavailability of different organic selenium (Se) products in finishing pigs. A total of 48 growing pigs, average body weight $47.6kg{\pm}0.05$, were allotted to four different treatments in a randomized complete block (RCB) design in three replicates with four pigs per pen. Three different organic Se products, Se-enriched yeast (treatments A and B) and Se-proteinate (treatment C), were used in conjunction with a basal diet with no added Se as a control treatment. In growing period, pigs were fed the same diet but finishing pigs were fed each treatment diet containing organic Se products for 6 weeks. During the experimental period, feed intake and body weight were measured and blood samples were collected to determine the Se concentration. At the end of this experiment, 3 pigs per treatment were killed and various tissues (loin, liver, kidney, pancreas and spleen) were collected to analyze the Se concentration. The body weight, and average daily feed intake (ADFI) were similar among treatments, but the average daily gain (ADG) was increased on Se-proteinate treatment (p<0.01) and gain-to-feed ratio (G/F ratio) was improved on Se yeast B or Se-proteinate treatment (p<0.01). The tissue Se content was also increased when pigs were fed organic Se sources, and Se was retained efficiently in loin (p<0.01) and kidney (p<0.05) when Se yeast B was provided. The serum Se concentration was increased when organic Se was provided and was higher when pigs were fed Se-proteinate (p<0.01); subsequently liver Se was also higher on Se-proteinate treatment than other treatments. The Se yeast A treatment did not show any increment of Se concentration both in serum and tissues. This result demonstrated that Se retention and bioavailability in finishing pigs were varied by Se products although organic sources were provided. Consequently, each organic Se product should be evaluated before it is used as a supplement in animal feed.

• Journal of Pharmaceutical Investigation
• /
• v.41 no.1
• /
• pp.9-17
• /
• 2011

The objective of this work is to study transdermal delivery of calcitonin using iontophoresis and to evaluate various factors which affect the transdermal transport. We have studied the effect of polarity, current density, drug concentration, penetration enhancers (isopropyl myristate [IPM] and ethanol) and laser treatment on transdermal flux and the results were compared. We also investigated the iontophoretic flux from microemulsions containing calcitonin together with oleic acid (OA) or IPM. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell and full thickness hairless mouse skin. Anodal delivery at pH 3.0 was much larger than cathodal and passive delivery, due to the positive charge of calcitonin. Cumulative amount delivered (CUM) by cathodal or passive delivery was close to zero for 10 hours. The pretreatment of skin by neat IPM markedly increased the CUM anodically. CUM increased as the current density, drug concentration or the duration of IPM treatment increased. Microemulsion containing IPM or oleic acid was prepared and the phase diagram was constructed. CUM also increased when IPM was incorporated into a microemulsion. OA microemulsion showed similar enhancing effect to IPM microemulsion. The delivery of calcitonin from 70% (v/v) ethanol aqueous solution showed a large increase in flux. Laser treatment of skin before flux experiment exhibited about 2 fold increase in total calcitonin amount transported for 12 hours, when compared to that delivered by IPM microemulsion. Based on these results, we have evaluated the possibility of delivering enough amount of calcitonin to reach the therapeutic level. The data suggest that it is highly possible to deliver clinically effective amount of calcitonin using iontophoresis patch with small area (<10 $cm^2$).

• BMB Reports
• /
• v.28 no.2
• /
• pp.112-117
• /
• 1995

Succinic semialdehyde reductase was inactivated by o-phthalaldehyde. The inactivation followed pseudo-first order kinetics, and the second-order rate constant for the inactivation process was 28 $M^{-1}s^{-1}$ at pH 7.4 and $25^{\circ}C$. The absorption spectrum ($\lambda_{max}$ 337 nm) and fluorescence excitation ($\lambda_{max}$ 340 nm) and fluorescence emission spectra ($\lambda_{max}$ 409 nm) were consistent with the formation of an isoindole derivative in the catalytic site between a cysteine and a lysine residue approximately about 3 $\AA$ apart. The substrate, succinic semialdehyde, did not protect enzymatic activity against inactivation, whereas the coenzyme NADPH protected against o-phthaladehyde induced inactivation of the enzyme. About 1 isoindole group per mol of the enzyme was formed following complete loss of enzymatic activity. These results suggest that the amino acid residues of the enzyme participating in a reaction with o-phthalaldehyde are cysteinyl and lysyl residues at or near the NADPH binding site.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.9
• /
• pp.1537-1543
• /
• 2008

We tested Trichoderma harzianum as a biocontrol agent for Rhizoctonia solani AG2-1, using six natural antifungal materials to improve its efficacy. Among the six materials tested, peony (Paeonia suffruticosa) root bark (PRB) showed the strongest antifungal activity against R. solani AG2-1, and was not antagonistic to T. harzianum. Scanning electron microscopy showed that treatment with PRB extract resulted in shortened and deformed R. so/ani AG2-1 hyphal cells. The control of radish damping-off caused by R. so/ani AG2-1 was greatly increased by combined treatments of T. harzianum and PRB, as compared with either of the two treatments alone, with the control effect increased from 42.3-51.5% to 71.4-87.6%. The antifungal compound in PRB, which was isolated in chloroform and identified as paeonol by mass spectrometry, $^1H$ NMR, and $^{13}C$ NMR analyses, inhibited the growth of R. so/ani AG2-1 but not that of T. harzianum. Thus, PRB powder or extract may be used as a safe additive to T. harzianum to improve the control of the soil borne diseases caused by R. so/ani AG2-1.