공기 중 유기용제 측정을 위한 흡착제 성능평가에 관한 연구

변상훈,박천재,오세민,이창하 ( Sang Hoon Byeon,Chun Jae Park,Se Min Ohe,Chang Ha Lee ) 한국화학공학회 1996 화학공학의이론과응용 Vol.2 No.1

Surface modified granular activated carbon for enhancement of nickel adsorption from aqueous solution

변상훈,Dhamodaran Kavitha,Kanagasabai Muruganandam Ponvel,Kyung-min Kim,이창하 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.6

Coal-based granular activated carbon was modified with acetates of sodium, potassium and lithium at concentrations of 10 and 15% and used as adsorbents to explore the adsorption mechanism of nickel ion in aqueous solution. Acetate treatment reduced surface area and pore volume of the activated carbons, but the adsorption amount of Ni(Ⅱ) on the modified activated carbons (MAC) was greater than that on the virgin activated carbon. The adsorption depended on pH of the solution with an optimum at 4.5 and the adsorbed nickel could be fully desorbed by using 0.05 M HCl solution. The maximum adsorption capacity of nickel ion on Li (15 wt%) modified activated carbon was 151.3 mg/g and the adsorption isotherm follows Langmuir, Sips, and Redlich-Peterson isotherm models better than the Freundlich isotherm model. The kinetic data was better fitted by a non-linear form of the pseudo-first order than the pseudo-second order, but the difference between two kinetic models was small.

일부 인쇄업 근로자의 유기용제 및 소음 노출에 관한 연구

변상훈,유인성,손종렬 대한환경위생공학회 1998 대한환경위생공학회지 Vol.13 No.3

아파트 실내에서 시간 경과에 따른 포름알데히드의 농도 조사

변상훈,김영환,손종렬,문경환 高麗大學校 倂設 保健大學 保健科學硏究所 2002 保健科學論集 Vol.28 No.1

Our communities have been exposed to polluted air. Polluted air could cause the serious injury such as respirational impediment, disease and so on, and the air pollution could be most serious problem in our life. Unfortunately, we didn't have consider these problems seriously, and we had make no solutions for these problems. The new apartment was shown higher concentrations for formaldehyde than the old apartment, that indicated the new apartment environment was more polluted.

확산 포집기를 이용한 공기중 유기용제 측정에 관한 연구

변상훈 高麗大學校 倂設 保健大學 保健科學硏究所 1997 保健科學論集 Vol.23 No.1

The laboratory and field tests for air monitoring of ethylacetate and toluene were carried by passive sampling methods and compared the results with using charcoal tubes. The results were as follows; 1. The mean desorption efficiencies of A, B passive monitors were over 85%. Those of B passive monitor for ethylacetate, however, had been increased to 17.5% by using the agitator for desorption. 2. The capacities of A, B passive monitor which had been exposed at the 2×STD for 8 hours were increased linearly with time increasing. So, A, B passive monitor were more suitable than charcoal tubes at long time exposure level. 3. As for the back diffusion, A passive monitors showed 8.4% concentration difference for ethylacetate and 5.0% for toluene and B passive monitors showed 1.2% for ethylacetate and 1.3% for toluene, respectively. Both of A, B passive monitors showed less than 10% difference. 4. As for the face velocity, A passive monitor showed less than 10% difference between high and low face velocity. But B passive monitors showed 12.7% difference between high and low velocity. So, they seemed to be affected by face velocity. 5. The uptake difference between low and high humidity showed very low values which were 0.8-3.3% for EAc and 0.1-0.2% for toluene. 6. The precision and accuracy for A, B passive monitors were also checked. The coefficients of variance for A B passive monitors were 2.3-4.0% for A passive monitors and 5.5-9.0% for B passive monitors. Overall accuracies for A passive monitors were ±14.2-14.8% and ±18.5-19.9% for B passive monitors. Overall accuracies for them were below 25% at the 95% confidence level. 7. The results of air monitoring by using passive monitors for ethylacetate and toluene were compared with the results of using charcoal tubes in gravers printing plants. The correlation between charcoal tubes and passive monitors were evaluated as Y=1.76X+37(r=0.81, p<0.05) for ethylacetate and Y=1.36X-49(r=0.93, p<0.06) for toluene.

아크릴 점착제의 최적물성에 관한 연구

변상훈,김중현 ( Sang Hoon Byeon,Jung Hyun Kim ) 한국공업화학회 1992 공업화학 Vol.3 No.4

기능성 단량체가 점착물성에 미치는 영향을 알아보기 위하여 아크릴산과 기타 단량체로 아크릴 수지를 라디칼 용액중합을 이용하여 4원공중합시킨 후 물성을 측정하였으며, 또한 최적 점착 물성을 얻기 위하여 통계적 분석 방법을 이용하여 검토하였다. 점착물성에 있어서 아크릴 산이 아크릴아미드보다 점착력의 증가에 미치는 영향이 컸다. 반면에 tackiness의 감소에 있어서는 아크릴아미드의 영향이 아크릴산 보다 컸다. 통계적 방법을 이용하여 점착물성 중 점착력, tackiness 그리고 웅집력을 최적화 시킨 결과 단량체의 성분 비율은 부틸 아크릴레이트 81.7 mole%, 아크릴산 8.0 mole%, 아크릴아미드 2.1 mole%, 비닐아세테이트 8.2 mole% 일 때로 나타났고 이 때의 추정 회귀식은 다음과 같았다. D = .857+.072X_1 -.114X_2-.027X_3-.126X_1^2-.046X_1·X_2-.063X_1·X_3-.152X_2^2+.027X_2·X_3-.120X_3^2 X_1:coded acylic acid, X_2:coded acylamide, X_3:coded vinylacetate The effects of functional monomers on the pressure sensitive adhesive proporties were studied. Acrylic acid and other monomers were copolymerized by radical solution polymerization and their properties were measured. The desirability function methodology was applied to obtain optimum pressure sensitive adhesive properties. Acrylic acid showed more effective than acrylamide on peel strength increase. On the other hand acrylamide showed more effective than acrylic acid on tack decrease. The optimum monomer ratio of the acrylic pressure sensitive adhesive recipe containing n-butylacrylate 81.7 mole%, acrylic acid 8.0 mole%, acrylamide 2.1 mole% and vinylacetate 8.2 mole% was obtained to result from the statistical analysis with the desirability function methodology. The estimated regression equation of desirability function(D) is as follows: D = .857+.072X_1 -.114X_2-.027X_3-.126X_1^2-.046X_1·X_2-.063X_1·X_3-.152X_2^2+.027X_2·X_3-.120X_3^2 X_1:coded acylic acid, X_2:coded acylamide, X_3:coded vinylacetate

일부 반면형 호흡기보호구 착용시 안면 크기 및 성별에 따른 밀착도 변화

변상훈,문경환,손종렬,김영환,배은상 高麗大學校 倂設 保健大學 保健科學硏究所 2000 保健科學論集 Vol.26 No.1

The fit of a respirator to the Face of an individual can be determined by a qualitative fit test((QLFT) or a quantitative fit test (QNFT). A quantitative fit test, was performed to evaluate leak values with Mask Fitting Tester. Two brands of half face respirators(M,S) were tested on 110 wearers on time. This study was investigated how the fit factors resulting from a quantiative fit test (QNFT) depend on the movements in the six test exersize regimes. Fit factor were low when face lengthes were higher or lower than average values. In this research we studies the koean's face length and compared the result with one of the American and the Japanese after wearing the Half-Mask Respirators, some changes in their leak were found and the results were as follows. 1. Although most testee were young, the Korean's face length were similar to the American while the male face length were similar to the Japanese. 2. For men, thier face length has been longer about by 1㎝ but mouth's length shorter about by 0.3㎝ than 10 years ago. 3. If the face length were not normality (such as higher or lower) leak degree was too high to be appropriate for the Respirator. 4. Both M and S company their respirators showed that the male leak degree was two times lower than female. Therefore, the resporators in the current market were believed to forcus it's target for male consumers. 5. The result of QLFT in a male showed that pass% of M was 20% higher than S. 6. In the result of QLFT, pass% of S was 25% highr than M in a female 7. These results(5&6) showed that S were more suitable in a female and M were more suitable in a male

실내·외 공기 중 휘발성 유기용제 포집을 위한 확산형 시료포집기의 성능변수에 대하여

변상훈 高麗大學校 倂設 保健大學 保健科學硏究所 1999 保健科學論集 Vol.25 No.1

Charcoal-based diffusive organic vapor monitors(OVMs) originally designed for sampling occupational exposures are increasingly being utilized to measure outdoor, indoor, and personal air concentrations of volatile organic compounds(VOCs). There has been very limited evaluation of the performance parameters of OVMs for use in nonoccupational environments where, typically, concentrations of VOCs are more than one order of magnitude lower than those found in usual industrial settings. The results of an extensive laboratory and field evaluation of the 3500 OVM(3M Company, St. Paul, MN, USA) indicate that OVMs can be used in community environments with 48-hour exposure durations with extensive modification of the extraction and analysis procedures. The OVM performance parameters for this type of application are presented, including analytical and method detection limits(MDLs), extraction efficiencies at ㎍-level loading, and optimum sampling times for indoor, outdoor and personal air monitoring in community environments.

부평역에서의 공기중 석면 노출 실태 및 인식도 조사

변상훈,주종순,손종렬 대한환경위생공학회 2003 대한환경위생공학회지 Vol.18 No.1

일부 반명형 호흡기 보호구에 대한 용접작업장에서의 Workplace Protection Factors(WPF) 평가

변상훈,임호섭,김현욱,나명채 한국산업위생학회 1999 한국산업보건학회지 Vol.9 No.1

This study was conducted to evaluate workplace protection factors(WPF) for two half-facepiece respirators (HR-1, HR-2) in welding workplace and to provide data on the workplace performance of negative-pressure, half-facepiece respirators against airborne particulate contaminants. The outside iron oxide(Fe2O3) concentration of welding fume for the respirator HR-1 ranged from 0.177 to 12.508 ㎎/m with a geometric mean of 1.118 ㎎/㎥ and the HR-2 respirator showed a iron oxide range of 0.500 to 3.494 ㎎/㎥ with a geometric mean of 1.082 ㎎/㎥. But the inside oxide concentration of welding fume for the respirator HR-1 ranged from 0.002 to 0.364 ㎎/㎥ with a geometric mean of 0.019 ㎎/㎥ and the HR-2 respirator showed a iron oxide range of 0.012 to 0.639 ㎎/㎥ with a geometric mean of 0.041 ㎎/d ㎥ The iron oxide inside concentrations were significantly less than 5 ㎎/㎥(TLV) for both of respirators. The WPF were ranged from 3 to 3744 with a geometric mean of 60 for HR-1 and range from 2 to 129 a geometric mean of 26 for HR-2. And, in this study, the 5th percentile of the workplace protection factors for half-facepiece aspirators (HR-1, HR-2) were 11.2 and 7.1, respectively. The correlation relationship between the Quantative Fit Factors(QNFT) and the WPF for half-mask negative pressure respirators were 0.099 and 0.460.