• Resources Recycling
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• v.7 no.1
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• pp.50-56
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• 1998

Basic oxygen furnace @OF) slag. a by-pradud of thc iron and steelmaking industry produced in largc quantities in Korea, poszs a subslantial disposal challenge. The BOF slag used in this study was if3 CaCO, in total n e u ~ ~ pnowger and application of 7-8 Mgha' was needed to bring soil pH to 6.5 horn pH 5.0-5.5 m silly clay or clay loam sod wnlained about 10% orgaoic matter. A field assay was conducted to shldg whether BOP slag could bc used as a dolomitic k i n g agent for agricullural soils. Four slag rates (0, 4, 8, 12 Mgha-')were investigated for their effcfect on soil pmperti~, mineral concentralions in leaf tissues of rice and soybean, and yield of the crops. Slag application at 8 Mgha-' rate in paddy field increased pH, Ca Mg, P, Si and Fe wntenl in sail and rice yield by 4.3-14.25 depending an the soil type. h upland field the 8 Mghaf ratc increa3ed pH, Ca and Fe wntent m soil and soybean yield by 36.6%. Thus, BOF slag appears to be a useful liming mate&\ulcornerl for corrzch~gs oil acidity on both paddy and upland ficld soils and for innwing Ca, Mg, P, Si, and Fe wncenhation in plants.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.82-88
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• 1999

In this study, to evaluate newly developed Japanese encephalitis (JE) vaccine candidate CJ50003, we assessed its immunogenicity along with a previously commercialized inactivated JE Biken vaccine. The CR0003 viral antigens produced in Vero cells were administered suhcutaneouly to mice either with alum-adjuvanled or free form. The ELISA titers and neutralizing (NEUV antibody titers accounting for major protective immunity in JE were determined. Mice given alum-adjuvanted vaccine had a 10 times higher antigen-specific NEUT antibody response than did those which {lad received free antigens. This NEUT antibody response was maintained until day 168 with NEUT titer more than 1:160. Even with the 0.5 ng of alum-adjuvanted antigen dose, NEUT titer was induced more than 1:10 which is considered as an evidence for seroconversion and protection. Thc mice immune sera had a similar rate of cross-reactivity against three different viral antigens, Nakayama-NlH, P3 and SA14; as determined by ELISA assay. In a mice challenge model, vaccination with the GI50003 conferred more protection than with commercialized Biken vaccine against Nakayama virus. These data demonstrated that CJ50003 vaccine candidate has an excellent prophylactic efficacy and implicated it has a strong potential for further development and commercialization.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.113-125
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• 2007

To know the differences in ionic compositions in rain and snow as well as snow influence on the chemical characteristics of winter precipitation, precipitation samples were collected by the wet-only automatic precipitation sample, in winter(November-February) in the Iksan located in the northwest of Chonbuk from 1995 to 2000. The samples were analyzed for concentrations of water-soluble ion species, in addition to pH and electrical conductivity. The mean pH of winter precipitation was 4.72. According to the type of winter precipitation, the mean pH of rain was 4.67 and lower than 5.05 in snow. The frequencies of pH below 5.0 in rain were about 73%, while those in snow were about 30%. Snow contained 3 times higher concentrations of sea salt ion components originated from seawater than did rain in winter, mainly $Cl^-,\;Na^+$, and $Mg^{2+}$. Neglecting sea salt ion components, $nss-SO_4^{2-}$ and $NO_3^-$ were important anions and $NH_4^+$ and $nss-Ca^{2+}$ were important cations in both of rain and snow. Concentrations of $nss-SO_4^{2-}$ was 1.3 times higher in rain than in snow, while those of $nss-Ca^{2+}$ and $NO_3^-$ were 1.5 and 1.3 times higher in snow, respectively. The mean equivalent concentration ratio of $nss-SO_4^{2-}/NO_3^-$ in winter precipitation were 2.4, which implied that the relative contribution of sulfuric and nitric acids to the precipitation acidity was 71% and 29%, respectively. The ratio in rain was 2.7 and higher than 1.5 in snow. These results suggest that the difference of $NO_3^-$ in rain and snow could be due to the more effective scavenging of $HNO_3$ vapor than particulate sulfate or nitrate by snow. The lower ratio in snow than rain is consistent with the measurement results of foreign other investigators and with scavenging theory of atmospheric aerosols. Although substantial $nss-SO_4^{2-}$ and $NO_3^-$ were observed in both of rain and snow, the corresponding presence of $NH_4^+,\;nss-Ca^{2+},\;nss-K^+$ suggested the significant neutralization of rain and snow. Differences in chemical composition of non-sea salt ions and neutralizing rapacity of $NH_4^+,\;nss-Ca^{2+}$, and $nss-K^+$ between rain and snow could explain the acidity difference of rain and snow. Snow affected that winter precipitation could be less acidic due to its higher neutralizing rapacity.

• Korean Journal of Poultry Science
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• v.19 no.1
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• pp.13-16
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• 1992

Avian infectious bronchitis virus(IBV) was propagated in SPF eggs and purified by sucrose density gradient centrifugation in order to prepare the antigen. Several fusions were made between mouse myeloma cells and spleen cells from BALB/c mouse immunized with IBV antigen and two hybridoma clones producing specific monoclonal antibody(MCA) against the IBV were established. The MCAs were classified as IgG type and revealed no neutralizing and hemagglutination inhibition activity. Using the MCA IBV antigen was detected by IFA method in tracheal smears made from chickens infected with IBV during the experimental period of 10 days.

• Resources Recycling
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• v.6 no.3
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• pp.28-35
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• 1997

Adsorption properities of hcavy metals (Cd, Cu, Fe, Mn, Pb, Zn) and organic compounds (Trichloroethylene and T Tetrachroethy len려 on sh$\xi$1I( oyster and ark shell) were investigated using wat$\xi$r treatment matenals, The shell powder (m띠or C crystal structurc is calcium hydroxide) showed the preference adsorption for heavy metals in order of Mn > Zn > Fe > Cd > eu > P Pb. The high removal capacities of heavy metals arc helicved to be largely due to precipitation by foonation of metal c carhonat,잃 and hydroxides at high pH caused by the $Ca(OH)_2$ component of sl1ell, immobilizatIon of heavy metals in a solid I matrix by calcium‘ and fixation by insoluble organic materials in the oystcr and ark shell. The use of sh려I in water treatment h has the potential to bc benefIcial as a source of inexpensive matcrials‘ moreover, not only treatment of waste but also e environmcntal business including environmental-purification ceramics could be better off by utili낌ng high-valued waste and d developed puri'fication ceramics and media.

• Journal of Food Hygiene and Safety
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• v.8 no.1
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• pp.55-61
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• 1993

Soil samples and the intestinal contents of arthropods, mollusca, pisces, aves, and mammals were examined for the presence of Clostridium botulinum. Demonstration of Clostridium botulimun was accomplished by identifying its toxin in liquid cultures inoculated with soil or material from the alimentary tract of tested animals with toxin neutralization tests in addition to morphological, cultural and biochemical tests. Incidences of Clostridium botulinum in tested samples were 5.0% in soil, 6.7% in mammal and 8.7% in fish, respectively. All of the positive cultures were identified as Clostridium botulinum type E and any other type was not demonstrated throughout the survey. Canned foods and solid ham/sausage mixture formulated as can with distilled water were inoculated with Clostridium botulinum type E and checked for toxin production by using the mouse bioassay. Clostridium botulinum type E toxin was produced as a large quantity in canned foods of fish, shell, meat and ham and, however, no significant toxin was detected in sausages and fruit samples.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.98-103
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• 2007

To isolate probiotic lactic acid bacteria for animal, we have screened the microorganisms from chicken feces, by random selection and agar well diffusion assay. Among them, CPM-7 strain showing superior inhibitory activity against Escherichia coli was selected. By examining carbohydrates utilization, morphologic property and 16S rRNA gene sequence, CPM-7 strain was identified as Lactobacillus salivarius, then named L. salivarius CPM-7. L. salivarius CPM-7 produced thirteen enzymes in the test using API ZYM kit, and showed resistance to low pH and bile salts. It survived at pH 2 for 30 min. and pH 3 for 6 hr. And, it was able to grow in MRS medium containing 0.2% (w/v) bile salts. L. salivarius CPM-7 adhered to the jejunal epithelium cells of pig. Both the supernatant of L. salivarius CPM-7 and the its neutralized one showed high inhibitory activity against E. coli K88.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1844-1846
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• 2001

광섬유는 저손실, 광대역의 전송특성을 가지며 세경(細徑), 경량등 많은 장점을 가지고 있지만 동케이블과 같이 파단점, 불연속점등의 장해점 탐색에 대한 어려움이 있다. 이러한 문제점을 해결하기 위하여 OTDR(Optical Time Domain Reflectometer)은 고감도, 고정도의 광센싱 기술, 극초단 광펄스 레이다 기술, 광다중화 센서 네트웍기술, 실시간 광신호처리 기술 등 정밀 광계측 및 신호처리기술을 적용하여 설치된 광섬유의 손실 정도를 측정하는 시스템으로 광섬유에 입사된 광의 산란 가운데 Rayleigh 산란에 의해서 생기는 후방산란광을 관측하여 광파이버의 파단점 탐색 및 손실측정이 가능하다. 최근 대부분의 유선통신망은 광섬유를 이용한 광통신방식으로 이루어지고 있으며 이러한 광섬유의 고장점을 찾기 위한 방법은 OTDR방식이 유일하다고 할 수 있다. 본 논문은 Rayleigh 후방산란에 의한 광학적 특성을 규명하고 이러한 특성을 이용하여 이용한 광섬유 유지보수용 계측시스템을 설계, 제작하고 실험한 결과에 대하여 설명하고 고찰하였다. 측정거리를 40Km까지 측정하도록 하였으며, 모니터상에서의 거리 분해능은 5m정도를 가지며 1310nm의 파장을 사용하였다.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.48-55
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• 2011

It was found that the absorbent mixed with 2-aminoethanol and others has been applied to remove them via chemical neutralization. The absorbent of natural second metabolites was achieved by a removal efficiency of 20~30% by itself depending on treatment conditions, but the complex absorbent mixed with 0.2% amine chemical provides the removal efficiency of over 98%. Optimal removal efficiencies have been examined against two major parameters of the temperature and pH to remove ammonia and hydrogen sulfide gases. The chemical analysis was also performed to analyze the composition of an essential oil by GC-MS. The monoterpenes in an essential oil reacted with odorous compounds by neutralization and their reaction mechanism was partially elucidated.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.25-34
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• 2014

The objective of this study was to investigate the removal characteristics and the elimination mechanism of heavy metals in Acid Mine Drainage (AMD) using spherical-type porous Zeolite-StarFish ceramics (porous ZSF ceramics) packed in a continuous column reactor system. The average removal efficiencies of heavy metals in AMD were Al 98.7, As 98.7, Cd 96.0, Cu 89.1, Fe 99.5, Mn 94.4, Pb 96.3 and Zn 80.8 % during 110 days of operation time. The average removal capacity of porous ZSF ceramics for heavy metals were measured to be Al 21.76, As 1.52, Cd 1.27, Cu 3.41, Fe 44.83, Mn 3.48, Pb 2.36 and Zn $3.76mg/kg{\cdot}day$. The analysis results of mechanism using SEM, EDS and XRD exhibited that the porous ZSF ceramics could act as a multi-functional ceramics for the removal of heavy metals in AMD through the reactions of precipitation, adsorption and ion-exchange. The experimental results of column reactor system displayed that the porous ZSF ceramics would be a consistently efficient agent for the removal of heavy metals in AMD for a long term.