• 한국산업보건학회지
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• 제4권2호
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• pp.208-223
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• 1994

The purpose of this study was to evaluate the efficiency of diffusive(or passive) sampler in measuring airbone organic solvents. Diffusive samplers are generally simple in construction and do not require power for operation. The efficiency of the diffusive samplers has not sufficiently been investigated in Korea. Three types of samplers were studied in this study. The sampling and analytical results by passive samplers were compared with results by charcoal tube method recommended by NIOSH(National Institute for Occupational Safty and Health). The following characteristics are identified and studied as critical to the performance passive monitors; recovery, reverse diffusion, storage stability, accuracy and precision, face velocity and humidity, n-Hexane, TCE(trichloroethylene) and toluene were used as test vapors. A dynamic vapor exposure system consisting of organic vapor generator and sampling chamber for evaluating diffusive samplers are made. The results of the study are summarized as follows. 1. NIOSH recommands that the overall accuracy of a sampling method in the range of 0.5 to 2.0 times the occupational health standard should be ${\pm}25$ percent for 95 percent confidence level. Among three types of diffusive samplers, sampler A has permeation membrane and samplers Band C have diffusive areas, samplers A and B met the criterion that overall accuracy for 95% confidence level of the samplers were within ${\pm}25$ percent of the reference value. Sampler C had overall accuracy ${\pm}9.6%$ and ${\pm}11.8%$ in hexane and TCE, respectively. The concentration of toluene was overestimated in sampler C with overall accuracy of ${\pm}43.9%$. 2. The desorption efficiencies of diffusive samplers were 96-107%. 3. There was no significant sampe loss during four weeks of storage both with and without refrigeration. 4. There was no significant reverse diffusion, when the samplers were exposure to clean air for 2 hours after sampling for 2 hours at the level of 2 TLY. 5. In case of 8 hours sampling, relative differences(RD) of concentrations between charcoal tube method and diffusive method were 15-39%, 13-46%, and 4-35% for sampler A, B and C, respectively. The performance was poor in 8 hours sampling for multiple substance monitors. 6. At high velocity(100 cm/sec), samplers B and C overestimated the concentrations of organic vapors, and sampler A with permeation membrance gave better results. 7. At 80% relative humidity, samplers showed no siginificant effect. Low humidity also did not affect the diffusive samplers.

• 한국식생활문화학회지
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• 제28권1호
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• pp.78-88
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• 2013

Marinated beef galbi is a traditional Korean dish cooked with soy sauce, pear juice, onion, sesame oil, and sugar. However, there are many differences in beef galbi, including flavor and physicochemical aspects, depending on cooking conditions. Therefore, the physicochemical characteristics of marinated beef galbi prepared through various recipes was evaluated for its effects on pH, texture, aging, proteolysis, heating conditions, cooking time, and flavor compounds (pyrazines, IMPs, or FAAs). There were significant differences in salt concentration (0.8~3.03%), pH (4.89~6.22), and solid soluble contents (1.34-6.31 Brix) between recipes in this study. In the Pearson assay for sensory evaluation, overall preference correlated well with texture (a well-known sensory attribute in meat evaluation). Controlling the pH of meat through soaking in lemon solution, alkali water, phosphate, and baking powder solution, improved water holding capacity as much as 9 to 15% compared with the control. The myofibril index (MFI) of marinated meat stored at $4^{\circ}C$ increased 32% with 24 hours of aging and reached 39% at 48 hours of aging, and its fragmentation was observed through microscopy. SDS-PAGE showed hydrolysis of acid-soluble collagen by the pear juice, possibly related to meat tenderness. On the basis of surface temperature, the cooking time was estimated to be 8 minutes with pan heating at $170^{\circ}C$, 6 minutes at $270{\sim}300^{\circ}C$, and 4 minutes with charcoal at $700{\sim}900^{\circ}C$. Different pyrazine compounds, such as 2-methyl-3-phenylpyrrol(2,3-b) pyrazine (the typical product of the browning reaction) was mainly detected, and IMP (one of the main taste compounds in beef) was in higher amounts with the charcoal treatment, potentially related to its flavor preference among treatments. Our results demonstrate an effective case study and cooking system for beef galbi.

• 식물조직배양학회지
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• 제26권2호
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• pp.103-107
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• 1999

Lilium oriental hybrid 'Casa Blanca'의 기내인편에서 자구를 대량생산하기 위하여 MS배지의 염류농도 및 당, 광조건 등이 자구의 형성 및 비대에 미치는 영향을 조사하였다. MS배지의 1/2～2배 염류농도에서 자구의 형성은 차이를 나타내지 않았으나 3배 염류농도에서 자구의 형성이 현저히 억제되었다 자구의 비대는 MS기본배지에서 가장 촉진되었다. 배지의 NH$_4$$^{+}$ : NO$_3$의 비율이 1 : 2와 1 : 3일 때, 또는 MS기본배지 (NH$_4$$^{+}$ : NO$_3$= 약 1 : 2)가 인편에서 자구의 형성 및 비대에 적절하였다. 따라서 MS 기본배지가 자구의 형성 및 비대에 양호한 것으로 나타났다. 당의 농도가 높아지면 자구형성은 억제되고 자구비대는 촉진되었으며, 당 9~12% 첨가배지에서 자구비대가 양호하였다. 배지내 활성탄의 첨가는 인편에서 자구의 형성을 억제하였으나 형성된 자구의 비대는 촉진하였다. 특히 활성탄 1 g/L를 첨가한 배지가 자구의 비대에 가장 효과적이었다. 자구의 형성 및 형성된 자구의 비대는 명, 암간에 차이를 나타내지 않았다. 따라서 L. Oriental Hybrid 'Casa Blanca'의 기내 대량번식은 당 9%와 활성탄 1 g/L가 첨가된 MS기본배지에서 기내인편을 배양하여 자구를 형성 및 비대시키고 형성된 자구의 인편을 계대배양하는 것이 효율적이었다.

• 생명과학회지
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• 제17권11호
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• pp.1555-1561
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• 2007

본 연구는 무기물성 및 식물성 유래 생리활성물질로서 scoria, germanium, charcoal, 생강, stevia 및 CLA(conjugated linoleic acid)가 병원성 미생물 및 반추위 미생물에 대한 작용을 조사하기 위하여 수행되었다. 병원성 균으로서 Escherichia coli O157, Salmonella paratyphi, Listeria monocytogenes 및 Staphylococcus aureus에 적용하여 항균활성을 측정하고, in vitro 발효 시 반추위 미생물 성장률, 가스 생성량, 암모니아 농도, CMCase 활성 및 미생물의 수를 측정하였다. 병원성 미생물 배양액에 생강을 0.1% 첨가한 구에서만 항균활성이 나타났으나, paper disc법에 의한 항균활성 시험에서는 stevia 10%첨가구와 CLA 10% 첨가구에서 E. coli에 대해서 항생제 첨가구인 positive control 구와 비슷한 크기의 clear zone을 형성하였다. in vitro 반추위 미생물 발효시험에서는 생강, stevia 및 CLA가 반추위 박테리아와 프로토조아의 증식을 억제하는 것으로 나타났는데, 특히 생강 첨가구의 경우 메탄 생성균의 서식지로 알려져 있는 프로토조아를 크게 억제함으로써 메탄생성 억제제로서 개발 가능성이 있는 것으로 사료된다.

• 한국산업보건학회지
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• 제11권3호
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• pp.241-248
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• 2001

The main factors of breakthrough are known to sampling time, flow rate, concentration of the sample, temperature, humidity, and the physical characteristics of the solid sorbent tube. However, no study has been reported the effect of temperature and sampling volume on the breakthrough of acharcoal tube during vinyl chloride monomer (VCM) sampling. The objective of this study is to suggest the optimal sampling condition during VCM sampling based on National Institute for Occupational Safety and Health (NIOSH) method. To evaluate adequate sampling volume for VCM without breakthrough, volume of 1, 2, 3, 4, and 5 L each from VCM of 1, 5, 10, 15, and 20ppm at flow rate of 0.05 L/min were sampled in $22^{\circ}C$ and $40^{\circ}C$. At $22^{\circ}C$, in the case of 1, 5, 10, and 15ppm, VCM was adsorbed completely in first section of charcoal tube regardless of sampling volume. But in 20ppm, detection rates are 99.56% in first section and 0.44% in second section. At $40^{\circ}C$ of 1ppm, VCM was adsorbed completely in first section. In 10, 15, and 20ppm, detection rates of second, third, and forth sections were decreased significantly by reduction of sampling volume. In determination of breakthrough based on NIOSH method, no breakthrough was occurred in 20ppm at $22^{\circ}C$. At $40^{\circ}C$, breakthrough was occurred in 10, 15, and 20ppm when sampling volume was 5L. Although no breakthrough was occurred when sampling volume was 3L. Finally, in environment of temperature around $22^{\circ}C$, breakthrough may not occurred up to 20ppm during sampling for VCM. During sampling for VCM in environment of temperature around $40^{\circ}C$, no breakthrough occurred in 1-5ppm and 10-20ppm when sampling volume is 5L and 3L respectively. This result suggests that the sampling volume should be considered when VCM sampling under hot conditions (> $22^{\circ}C$) by the NIOSH method No. 1007.

• 한국환경농학회지
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• 제30권2호
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• pp.160-165
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• 2011

시설재배지내의 밀폐공간에서 토양처리농약의 살포 후 농작업으로 작업자의 농약중독 우려가 상존하므로 농약중독예방 방지를 위해 살포농약의 휘산양상과 농작업자 노출량 산정 연구를 수행하였다. 흡착제를 이용한 공기 중 ethoprophos, cardusafos, probenazole의 회수율은 각각 charcoal 흡착제 80.9~121.1%, XAD-4 흡착제가 90.6~99.0% 수준으로 양호하였다. lysimeter에 토양을 혼화처리 한 후 온도별 농약의 휘산은 온도가 높을수록 휘산이 잘되었으며, 특히 수분이 존재 하는 $35^{\circ}C$조건에서는 ethoprophos의 경우 3~5배 휘산량이 증가하였다. 면적 245 $m^2$ 시설하우스 재배포장에서 ethoprophos 입제를 150 g (a.i.) 토양과 혼화처리하고 지면으로부터 50 cm 상층에서 처리 46시간까지 토양처리제인 ethoprophos의 휘산량은 17.8~186.4 ${\mu}g/m^3$이었다. 동일조건에서 cadusafos 180 g a.i./245 $m^2$ 약량을 처리했을 때 처리 39시간째에 최고 농도를 보였으며 46시간까지 공기중농도는 10.0~37.3 ${\mu}g/m^3$이었다. Probenazole은 144 g a.i./245 $m^2$ 약량을 처리했을 때 처리 37시간째에 최고 농도를 보였으며 46시간까지의 공기중 농도는 0.23~1.45 ${\mu}g/m^3$ 수준이었다. 약제처리 후 하우스내 공기중 농약성분의 최대잔류량은 13~39시간 사이에 최대잔류가 되었고 토양처리농약인 ethoprophos 입제와 cadusafos 입제는 휘산성이 높음으로 농작업자 재출입 기간은 살포 후 48시간 이후로 설정해야 할것이다.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.229-235
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• 2007

음나무의 체세포배를 이용하여 인공종자를 조제하고 발아에 미치는 알진산 농도, 체세포배의 크기, 종피내 첨가물 그리고 인공상토 (펄라이트)에 파종시 입자의 크기 및 수용액 처리에 따른 발아율을 조사한 결과는 다음과 같이 요약 될 수 있다. 1. 알진산의 농도는 3%로 인공종피를 조제함이 차후 정상적인 발아에 좋은 것으로 나타났고, 알진산 농도가 증가할수록 발아율은 감소하는 경향이었다. 발아배지는 0.02% 활성탄이 첨가된 1/2 MS 배지에서 다소 양호하였다. 2. 체세포배의 크기에 따라서는 $1.5{\sim}5.0\;mm$의 체세포배를 사용하였을 때 인공종자의 발아에 크게 영향이 없었다. 따라서 인공종자화를 위한 체세포배의 크기는 배의 발달단계에 따라 다소 작거나 큰 체세포배를 사용해도 발아에 문제가 없음을 보여주었다. 3. 인공종자의 정상적인 발아를 위해서는 종피 조제시 첨가물이 중요하게 나타났다. 증류수를 첨가시에는 발아가 매우 저조하게 나타났으며, MS 배지 염류를 첨가시키는 것이 발아 및 차후 생장에 좋은 것으로 나타났다. 4. 인공종자의 발아율은 종피내 함유물이 발아에 크게 영향하여 양료배지를 첨가시에 발아에 양호하였다. 인공종자의 발아는 1% gelrite로 고형화 시킨 배지에서도 발아가 가능하지만 발아 후의 정상적인 생장은 억제되는 것으로 나타나 종피에 배지를 첨가하고, 발아배지 또한 양료 배지를 사용하는 것이 발아후의 식물체 생장에 중요한 요인으로 나타났다. 이 같은 결과는 음나무의 발아 및 유묘의 생장에는 양료의 요구도가 높다는 것을 시사한다. 5. 인공종자를 상토에 직접 파종하여 발아율을 조사한 결과 발아율은 3% sucrose 수용액 처리시 전체적인 발아율이 가장 양호하게 나타났고 증류수 처리시는 거의 발아되지 않았다. 상토입자의 크기에 따라서는 발아율에 현저한 차이를 보이지 않았다.

• 한국환경농학회지
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• 제19권5호
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• pp.401-418
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• 2000

1. Production of the artificial zeolite from coal ash Coal fly ash is mainly composed of several oxides including $SiO_2$ and $Al_2O_3$ derived from inorganic compounds remained after burning. As minor components, $Fe_2O_3$ and oxides of Mg, Ca, P, Ti (trace) are also contained in the ash. These components are presented as glass form resulting from fusion in the process of the combustion of coal. In other word, coal ash may refer to a kind of aluminosilicate glass that is known to easily change to zeolite-like materials by hydrothermal reaction. Lots of hot seawater is disposing near thermal power plants after cooling turbine generator periodically. Using seawater in the hydrothermal reaction caused to produce low price artificial zeolite by reduction of sodium hydroxide consumption, heating energy and water cost. As coal ash were reacted hydrothermally, peaks of quartz and mullite in the ash were weakened and disappeared, and new Na-Pl peaks were appeared strengthily. Si-O-Si bonding of the bituminous coal ash was changed to Si-O-Al (and $Fe^{3+}$) bonding by the reaction. Therefore the produced Na-Pl type zeolite had high CEC of 276.7 $cmol^+{\cdot}kg^{-1}$ and well developed molecular sieve structure with low concentration of heavy metals. 2. Utilization of the artificial zeolite in agro-environment The artificial zeolite(1g) could remove 123.5 mg of zinc, 164.7 mg copper, 184.4 mg cadmium and 350.6 mg lead in the synthetic wastewater. The removability is higher 2.8 times in zinc, 3.3 times in copper, 4.7 times in cadmium and 4.8 times in lead than natural zeolite and charcoal powder. When the heavy metals were treated at the ratio of 150 $kg{\cdot}ha^{-1}$ to the rice plant, various growth inhibition were observed; brownish discoloration and death of leaf sheath, growth inhibition in culm length, number of panicles and grains, grain ripening and rice yield. But these growth inhibition was greatly alleviated by the application of artificial zeolite, therefore, rice yield increased $1.1{\sim}3.2$ times according to the metal kind. In addition, the concentration of heavy metals in the brown rice also lowered by $27{\sim}75%$. Artificial Granular Zeolites (AGZ) was developed for the purification of wastewater. Canon exchange capacity was 126.8 $cmol^+{\cdot}kg^{-1}$. AGZ had Na-Pl peaks mainly with some minor $C_3S$ peaks in X-ray diffractogram. In addition, AGZs had various pore structure that may be adhere the suspended solid and offer microbiological niche to decompose organic pollutants. AGZ could remove ammonium, orthophosphate and heavy metals simultaneously. Mixing ratio of artificial zeolite in AGZs was related positively with removal efficiency of $NH_4\;^+$ and negatively with that of $PO_4\;^{3-}$. Root growth of rice seedling was inhibited severely in the mine wastewater because of strong acidity and high concentration of heavy metals. As AGZ(1 kg) stayed in the wastewater(100L) for 4days, water quality turned into safely for agricultural usage and rice seedlings grew normally.

• 한국산업보건학회지
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• 제19권4호
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• pp.321-327
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• 2009

1,3-butadiene is classified as suspected human carcinogen, group A2(American Conference of Governmental Industrial Hygienists, ACGIH). In Korea, 1,3-butadiene has been used as a raw material; monomer, homopolymer, polybutadiene latex, acrylonitrile-butadiene-styrene(ABS) and styrene-butadiene rubber(SBR), in the petrochemistry and precision chemistry industry. As petrochemistry industry in Korea has been developed, the potential exposure possibility of 1,3-butadiene to workers can be increased. Therefore the purpose of this study is to evaluate airborne 1,3-butadiene concentration and workers' exposure levels in the workplace using 1,3-butadiene. Air samples were collected with 4-tert-butyl catechol(TBC) charcoal tube(100 mg/50 mg) and were analyzed by gas chromatograph/flame ionization detector(GC/FID) according to the Choi's method(2002). Geometric mean (GM) and arithmetic mean (AM) of total 59 workers' exposure concentrations to airborne 1.3-butadiene were 0.042 ppm and 1.51 ppm, respectively. Although most samples were lower than 1ppm, 2 samples(21.5ppm and 33.1ppm as 8hr-TWA) were exceeded the Korean standard(2ppm) over 10 times at the repair process in synthetic rubber and resin manufacture industry. 14 samples(41%) of total 34 short-term air samples were exceeded the Korean standard(10ppm as STEL) of Ministry Labor. 1,3-butadiene concentration(GM) in the synthetic rubber and resin manufacture industry(7.87ppm) was significantly higher than that in the monomer manufacure industry (0.35ppm)(p<0.05). Also in the sampling and repair process, each GM(range) was 1.39ppm(N.D.-469.6ppm) and 7.85ppm(N.D.-410.2ppm). In conclusion, it depends on the industry and process, 1,3-butadiene can be exposed to workers as high concentration for short-term.

• 한국작물학회지
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• 제40권5호
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• pp.619-628
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• 1995

본 실험은 온실과 포장에서 재배한 알팔파를 잎, 줄기, 뿌리, 꽃 부분으로 나누어 수확, 건조,하여 물 추출한 후 이 추출물들이 알팔파 발아와 생육에 미치는 영향을 조사 비교하였으며 포장상태에서 자란 알팔파 지상부 전체를 수확,건조, 추출하여 이를 농도별로 처리 알팔파 발아율을 검정하였고, pot실험을 통하여 알팔파 품종간 biomass 분배율 검정과, 알팔파 autotoxicity를 해결하기 위한 방법으로 추출물을 adsorbent로 처리하여 이들이 알팔파 독성성분을 변형시키는지를 검토하였다. 1. 온실과 포장에서 자란 알팔파의 추출물로 알팔파 발아 및 생육에 대한 영향을 비교한 결과 포장에서 자란 추출물질이 발아와 생육에 더 억제적으로 작용하였고, 특히 포장에서 생육한 꽃 추출물 처리가 가장 억제적으로 작용하였다. 2. 농도처리에 따르는 추출물 처리는 농도가 증가 할수록 발아율이 억제되었고, biomass분배율에 대한 pot실험에서는 LWR 과 SLA의 산물인 LAR은 품종간 유의성을 보였다. 3. 알팔파 추출물에 대한 absorbents처리는 추출물의 독성을 변형시키지 못하였다.