• 한국안전학회지
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• 제32권4호
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• pp.16-21
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• 2017

The sprinkler system is a basic fire extinguishing system that uses water as an extinguishing agent. In order to evaluate the fire extinguishing performance of the sprinkler system, information such as the discharge angle, discharge speed, discharge pressure, flow rate, and water droplet size of the installed head are required. However, there is a lack of research on droplets size compared to other requirements. In this study, to evaluate the extinguishing characteristics of sprinkler system, the droplet size distribution was measured for various types of sprinkler heads actually used. The size of the droplet was measured using laser diffraction method. The 50% cumulative volume distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the distribution ($D_{v50}$) according to discharge coefficient(K factor) was $540{\mu}m{\sim}695{\mu}m$ for K50, $542{\mu}m{\sim}1,192{\mu}m$ for K80, $980{\mu}m{\sim}1,223{\mu}m$ for K115 and $1,188{\mu}m{\sim}1,234{\mu}m$ for K202. Based on the measured results, the vaeiance of the droplet particle distribution and the Rosin-Rammler index value are presented. As a result of the fire simulation with FDS, it was confirmed that the performance difference occurs according to the water droplet size distribution even when the same amount of water is used. Therefore, the extinguishing performance of the sprinkler system should be evaluated considering the droplet size distribution according to the sprinkler head type.

• 한국치위생학회지
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• 제12권1호
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• pp.81-91
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• 2012

Objectives : By investigating antimicrobial activity of natural extracts, identifying its usefulness as antibiotic material to oral bacteria. Methods : Antimicrobial activity tests of 25 natural extracts were implemented on 6 type strains alleged to cause dental caries and 10 clinical strains isolated and identified from dental caries. Results : Among medicinal plants, Coptis japonica, Scutellaria baicalensis, Dictamnus dasycarpus showed antimicrobial activity. Among lichens, 3 methanol extracts and 6 acetone extracts showed antimicrobial activity. Minimum Inhibitory Concentration(MIC) test of Usnea aurantiacoatra KoLRI 004184, an acetone extract of lichen with the highest antimicrobial activity, on 6 type strains involved in dental caries and 10 strains isolated from dental caries resulted as follows; Actinomyces oris 1041 $12{\mu}g/ml$, for Corynebacterium durum 3151 $13{\mu}g/ml$, for Rothia dentocariosa KCTC $3204^T$ $14{\mu}g/ml$, for R. dentocariosa 911 $15{\mu}g/ml$, for R. dentocariosa 1822 $12{\mu}g/ml$, for Lacto-bacillus casei KACC $12413^T$ $12{\mu}g/ml$, for L. acidophilus KACC $12419^T$ $16{\mu}g/ml$, for L. rhamnosus 2421 $15{\mu}g/ml$, for Streptococcus mutans KCTC $3065^T$ $15{\mu}g/ml$, for S. mutans 121 $13{\mu}g/ml$, for Streptococcus oralis 2221 $18{\mu}g/ml$, for S. salivarius KCTC 5512 $14{\mu}g/ml$, for S. salivarius 122 $12{\mu}g/ml$, for S. sanguinis KCTC $3284^T$ $14{\mu}g/ml$, for S. sanguinis 912 $14{\mu}g/ml$, for Neisseria sp. KEM232 $12{\mu}g/ml$. Conclusions : Even a small amount of extract from lichen Usnea aurantiacoatra KoLRI 004184 showed very high level of antimicrobial activation against all 16 bacterial strains involved in dental caries.

• 한국환경과학회지
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• 제11권4호
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• pp.391-397
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• 2002

Carbamate 농약에 대한 cholinesterase(ChE)활성저해 관계를 규명 하고자 in vivo와 in vitro 실험을 하였다. ChE의 최적 pH는 8.0이었다. 병아리 혈장의 ChE 활성은 기질로 acetylcholin를 사용할 경우 24.6 $\mu$mol/min/g protein이었다. in vivo에서 BPMC을 0.32 mg/kg 경구 투여한 15분 후에 ChE 활성이 60%까지 저해되었으며 그 후 12시간 후에 97% 까지 회복이 일어났다. in vitro에서 효소 활성이 50%로 저해되는데 필요한 농도인 I$_{50}$이 Phenyl N-methylcarbamate계에 XMC는 329 $\mu\textrm{g}$/$\ell$였고, metolcarb은 214 $\mu\textrm{g}$/$\ell$였다. BPMC는 111 $\mu\textrm{g}$/$\ell$, propoxur는 107 $\mu\textrm{g}$/$\ell$, isoprocarb는 104 $\mu\textrm{g}$/$\ell$이었다. Aromatic N-methylcarbamate계에 속하는 carbaryl의 I$_{50}$은 280 $\mu\textrm{g}$/$\ell$이었고, carbofuran 114 $\mu\textrm{g}$/$\ell$이었다.이었다.

• 한국식품영양과학회지
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• 제29권1호
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• pp.99-105
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• 2000

The purpose of this study was to evaluat the Zn, Cu, Mn and Ni status and correlation of their concentrations in serum, urine, hair and fingernail in female college students. As the results are follows; The mean age of subjects was 22.5 years and height, weight and BMI were 160.1 cm, 51.0 kg and 20.0 respectively. The daily intake of energy 1769.5 kcal and the ratio of carbohydrate, fat and protein for energy is 60 : 20 : 15. The daily intake of energy (88.5%), vitamin B2 (86.1%), Ca (75.4%), Fe (58.3%) and Zn (63.0%) of subjects did not reach to Korean Recommended Dietary Allowance (RDA). The daily mean intake of Zn, Cu, Mn and Ni were 7.56 mg, 2.30 mg, 3.81 mg and 0.18 mg respectively. The concentrations of Zn in serum, urine, hair and nail were 85.6$\mu\textrm{g}$/dL, 391.2$\mu\textrm{g}$/day, 174.6$\mu\textrm{g}$/g and 102.4$\mu\textrm{g}$/g respectively and those Cu were 84.2$\mu\textrm{g}$/dL, 56.6 $\mu\textrm{g}$/day, 20.3$\mu\textrm{g}$/g and 4.3$\mu\textrm{g}$/g respectively. The concentrations of Mn in serum, urine, hari and nail were 0.2$\mu\textrm{g}$/dL, 1.1$\mu\textrm{g}$/day, 1.8$\mu\textrm{g}$/g and 1.6$\mu\textrm{g}$/g respectively and those of Ni were 0.6$\mu\textrm{g}$/dL, 24.5$\mu\textrm{g}$/day, 3.5$\mu\textrm{g}$/g and 3.1$\mu\textrm{g}$/g respectively. The daily intake of Mn showed the positive correlations with concentration of Mn in hair (p<0.05) and the daily intake of Ni was positively correlated with urinary exretion (p<0.05) and hair contents (p<0.001) of Ni. The more detailed studies about these trace mineral status should be required.

• Nuclear Engineering and Technology
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• 제5권4호
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• pp.279-285
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• 1973

생체 시료 중에 함유된 수은, 브롬, 비소 및 카드뮴을 동시에 정량하였다. 시료를 원자로에서 중성자 조사 한다음 휘발성 물질인 수은과 브롬은 중류법을 사용하여 분리한다음 감마선 분광법으로 정량하였다. 그리고 비소와 카드뮴은 양이온 교환수지를 이용하여 계속분리하여 역시 감마선 분광법으로 정량하였다. 수은, 브롬, 비소 그리고 카드뮴의 정량한계는 각각 0.002$\mu\textrm{g}$, 0.003$\mu\textrm{g}$, 0.001$\mu\textrm{g}$ 및 0.02$\mu\textrm{g}$이었다. 이 분석 방법을 사용하여 쌀및 생선시료 중의 수은, 브롬, 비소 및 카드윰을 정량하였다. 그리고 동방법을 사용하여 표준시료인 배추가루를 분석할 결과 수은이 0.046$\mu\textrm{g}$/gr, 브롬이 24.5$\mu\textrm{g}$/gr 비소가 0.17$\mu\textrm{g}$/gr이었고 카드뮴은 0.50$\mu\textrm{g}$/gr이었다.

• 한국전자통신학회논문지
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• 제7권1호
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• pp.125-134
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• 2012

본 연구는 대기중에 포함된 미세먼지(PM10: 지름 $10{\mu}m$ 이하크기의 미세먼지)가 위성신호전송주파수대역에 미치는 영향을 해석하기 위한 것으로, 미세먼지 농도별 위성신호감쇠 정도를 해석을 위하여 $50{\mu}g/m^3$이하, $100{\mu}g/m^3$이하, $200{\mu}g/m^3$, $400{\mu}g/m^3$이하, $800{\mu}g/m^3$이하, $1,600{\mu}g/m^3$이하, $3,200{\mu}g/m^3$이하로 총 7단계로 분류하여 해당 농도가 위성신호에 미치는 영향을 정량화 하는 연구이다.

• 생약학회지
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• 제28권4호
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• pp.233-238
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• 1997

ln order to search for antigastric cancer agents from Korean traditional prescriptions. We selected 41 traditional prescriptions, based on a review of the Korean traditional medicine books. Both boiling water and methanol extracts were tested, by means of the Sulforhodamine B (SRB) protein assay. Six of the 41 water extracts; #3, #34, #35, #38, #40, #41 showed efficacy against gastric cancer cell (AGS: Human gastric carcinoma, ATCC HTB 103). #3 inhibited 50% cancer cell growth1 at the concentration of $152\;{\mu}g/ml$, #34, #35, #38, #40 and #41 inhibited 50% cancer cell growth at the concentration of $145\;{\mu}g/ml$, $129\;{\mu}g/ml$, $173\;{\mu}g/ml$, $10\;{\mu}g/ml$ and $19\;{\mu}g/ml$ respectively. Ten of the 41 methanol extracts; #1, #3, #32, #33, #35, #36, #37, #38, #41 were active. #1 inhibited 50% cancer cell growth at the concentration of $206\;{\mu}g/ml$, #3, #32, #33, #35, #36, #37, 738, #40, #41 inhibited 50% cancer cell growth at the concentration of $133\;{\mu}g/ml$, $159\;{\mu}g/ml$, $199\;{\mu}g/ml$, $147\;{\mu}g/ml$, $113\;{\mu}g/ml$, $187\;{\mu}g/ml$, $130\;{\mu}g/ml$, $9\;{\mu}g/ml$, $15\;{\mu}g/ml$ respectively. Prescription #3, #35, #38, #40, #41 were also interesting because both methanol and water extracts were active.

• 분석과학
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• 제21권1호
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• pp.53-57
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• 2008

주류 중 에틸카바메이트의 함량을 조사하기 위해 시중에 유통되는 시료를 고체상 정제컬럼(충진제: 규조토)에 흡착시켜 디클로로메탄으로 용출시킨 후 GC/MS-SIM 방법에 의해 분석하였다. 적용된 분석법의 회수율은 85.2-87.9% 이었으며 변이계수는 0.7-1.9%, 검출한계는 $2{\mu}g/kg$, 정량한계는 $10{\mu}g/kg$이었다. 에틸카바메이트의 함량을 조사한 결과는 대상 주류의 유형에 따라 검출수준에 차이를 나타냈으며, 평균 검출수준은 리큐르 $194{\mu}g/kg$, 과실주 $105{\mu}g/kg$, 일반증류주 $62{\mu}g/kg$, 청주 $28{\mu}g/kg$, 약주 $15{\mu}g/kg$, 기타 주류 $12{\mu}g/kg$, 소주 불검출 이었다.

• 해양환경안전학회지
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• 제21권1호
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• pp.9-17
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• 2015

국내 대형 조선소 주변해역의 중금속오염 현황을 밝히기 위하여 2010년 여름에 4개의 대형 조선소 주변 11개의 채수정점과 4개의 대조정점에서 해수 시료를 채취하여 6종의 금속(Cu, Zn, Fe, Cd, Pb, Hg)을 분석하였다. 조선소별 주변해역 수중의 금속을 분석한 결과, (1) 구리(Cu)의 평균 농도는 $0.817{\sim}1.638{\mu}g/L$로 해역환경기준(사람의 건강보호기준 $20{\mu}g/L$, 해양생태계 보호 단기기준 $3{\mu}g/L$)보다 낮았지만, 대조정점에 비하여 1.64~2.75배의 높은 값을 나타냈다. (2) 아연(Zn)의 평균 농도는 $ 0.228{\sim}0.567{\mu}g/L$로 해역환경기준(사람의 건강보호기준 $100{\mu}g/L$, 해양생태계 보호 단기기준 $34{\mu}g/L$)보다 낮았지만, 대조정점에 비하여 1.62~5.91배의 높은 값을 나타냈다. (3) 철(Fe)의 평균 농도는 $3.332{\sim}7.410{\mu}g/L$로 대조정점에 비하여 1.30~6.75배의 높은 값을 나타냈다. (4) 카드뮴(Cd)의 평균 농도는 $0.013{\sim}0.028{\mu}g/L$로 해역환경기준(사람의 건강보호기준 $10{\mu}g/L$, 해양생태계 보호단기기준 $19{\mu}g/L$)보다 낮았지만, 대조정점에 비해 1.18~2.33배의 높은 값을 나타냈다. (5) 납(Pb)의 평균 농도는 $0.007{\sim}0.126{\mu}g/L$로 해역환경기준(사람의 건강보호기준 $50{\mu}g/L$, 해양생태계 보호 단기기준 $7.6{\mu}g/L$)보다 낮았다. (6) 수은(Hg)의 평균 농도는 $0.002{\sim}0.004{\mu}g/L$로 해역환경기준(사람의 건강보호기준 $0.5{\mu}g/L$, 해양생태계 보호 단기기준 $1.8{\mu}g/L$)보다 낮았다. 비록 모든 중금속의 수중 농도가 해역환경기준보다 낮다고 할지라도, 선박 건조작업에 사용되는 구리, 아연, 철과 같은 중금속의 농도가 대조해역에 비해 조선소 주변해역에서 높다는 것은 조선소의 영향에 기인하는 것을 암시한다. 따라서 조선소로부터 각종 오염물질이 해양에 유입되지 않도록 통제하고 해양오염을 방지하는 국가적 차원의 해양환경관리가 필요하다.

• 대한한방종양학회지
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• 제7권1호
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• pp.39-60
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• 2001

Fuzhengfangaitang is a prescript for inhibiting recurrence and metastasis of cancer. We had examined the anti-metatstastic effect of Fuzhengfangaitang. Furthermore, we performed the following experiments with ingredients of Fuzhengfangaitang. The purpose of this thesis is to study what ingredients of Fuzhengfangaitang have more valuable anti-cancer effects. And the results are listed below: 1. Cell Viability assay At the dose of 400$\mu$g/ml, most ingredients of Fuzhengfangaitang depressed viability of ECV-304. And especially, Scutellaria barbata D. DON$50{\mu}g/ml$ : 53.118%, $100{\mu}g/ml$: 49.092%, $200{\mu}g/ml$ : 43.765%, $400{\mu}g/ml$ : 12.747%), Polygonum bistorta L.($50{\mu}g/ml$ : 45.554%, $100{\mu}g/ml$ : 45.554%, $200{\mu}g/ml$ : 0.0%, $400{\mu}g/ml$ : 0.0%) and Psoralea corylifolia L.($50{\mu}g/ml$ : 86.591%, $100{\mu}g/ml$ : 81.307%, $200{\mu}g/ml$ : 24.801%, $400{\mu}g/ml$ : 3.111%) highly depressed cell viability more than the other ingredients. (${\alpha}$<0.05) 2. Cell Proliferation assay Proliferation assay with ingredients of Fuzhengfangaitang on ECV-304 showed that Crataegus pinnatifuda BGE ($50{\mu}g/ml$: 63.276%, $100{\mu}g/ml$ : 64.092%, $200{\mu}g/ml$ : 68.966% $400{\mu}g/ml$ : 38.517%, ED50=$296.974{\mu}g/ml$), Polygonum bistorta L.($50{\mu}g/ml$ : 83.981%, $100{\mu}g/ml$ : 86.997%, $200{\mu}g/ml$ : 58.780%, $400{\mu}g/ml$ : 26.408%), ED50=$266.725{\mu}g/ml$) and Psoralea corylifolia L.($50{\mu}g/ml$ : 103.037%, $100{\mu}g/ml$ : 82.529%, $200{\mu}g/ml$ : 2.829%, $400{\mu}g/ml$ : 0.998%), ED50=$177.369{\mu}g/ml$) depressed cell proliferation more than the other ingredients. 3. Tube Formation assay Compared with the control group, most ingredients of Fuzhengfangaitang did not remarkably inhibited the Tube Formation assay of ECV-304 at the dose of $100{\mu}g/ml$. But, Polygonum bistorta L. highly inhibited the tube formation of ECV -304 at the lower dose of $50{\mu}g/ml$. 4. Rat Aortic Ring assay In comparison with the control group, Scutellaria barbata D. DON., root of Polygonum bistorta L. and Psoralea corylifolia L. restricted the angiogenesis of the rat aortic ring at the dose of $100{\mu}g/ml$. And the other ingredients of Fuzhengfangaitang did not restricted the angiogenesis of the rat aortic ring at that dose. Especially, Polygonum bistorta L. highly inhibited the angiogenesis of the rat aortic ring at the lower dose of $50{\mu}g/ml$. From our research, the anti-angiogenic effects of the ingredients of Fuzhengfangaitang was proven. Moreover, it will be helpful for designing more effective prescription for anti angiogenesis.