Formulation Prediction for Young's Modulus of Poly(dimethylsiloxane) by Spectroscopic Methods

Cho Han Saem,Moon Heh‐Young,Lee Heung Soon,Kim Yong Tae,Jeoung Sae Chae 대한화학회 2021 Bulletin of the Korean Chemical Society Vol.42 No.9

In this work, we refer to the fraction of hydrides and vinyl groups consumed in cross-linking reaction as a variation of the properties of poly(dimethylsiloxane) (PDMS) with varying the formulation of a curing agent from 3.2 wt % to 50 wt %. Young’s modulus, density, and refractive indices of PDMS were observed to have a maxima at a formulation of about 10 wt % of cross linker. The intensity of the Raman band for the Si H stretching mode in cross-linker is almost zero if the cross-linking agent is less than 10 wt %, but it is linearly increasing with increasing the content of cross-linker. The dependence of the elastic modulus on the formulation could be explained in terms of the fraction of cross-linked network. The analytical framework proposed in this work could be used for optimizing the formulation of PDMS and hence its properties can be tailored for specific applications.

확대행렬의 고유치감도를 이용한 미소신호안정도 해석

문채주,장영학,심관식 木浦大學校 工業技術硏究所 1998 工業技術硏究誌 Vol.8 No.-

New eigen-sensitivity theories of the augmented matrix are applied to small signal stability analysis of EPRI one-machine infinite-bus system and New England 10-machine 39-bus test system. First and second order eigenvalue sensitivities are computed for changes of the parameters of line reactance and controllers including exciter, turbine/governor and PSS. It is found in many cases that since eigenvalue trajectories for parameter changes are nonlinear and first order estimate is not adequate for relatively large variation in parameters. Hence second order estimate is essential to guarantee accuracy for wide range of parameter changes.

일반주거지역내 도로에 의한 사선제한 규정에 관한 연구

문석,어인준,채원연,이원근,김영하 대한건축학회 2003 대한건축학회논문집 Vol.19 No.8

The height provisions, by the urban planning, describe the hightest height per width division, also define oblique line limitation by road without mentioning the highest per width division. Therefore this study will be a basic model for the standard of measuring the highest height per width division analysizing the propricty of current standard of oblique limitation. This technique is prepared to prevent the confusion and to complements the existing planning method. Therefore, it takes more time to establish this new method and to apply it to the existing condition. This study reviewed density control in District Units Plan, based on the guidelines of density, which included height, ratio of total floor to ground area, and land distribution. This study aims to provide efficient analysis by using current oblique limitation provisions. Thus, proving the area rations of general residential areas are decreasing. Since the purpose of the District Units Plan is to avoid confusion and help case the existing problematic conditions which have risen from the two above-mentioned conventional systems, further observation and research on these areas are necessary.

도금사업장의 작업환경의 유해인자 노출수준에 관한 연구

문덕환,도수영,이채관,황용식,선병관,손병철,김대환,이창희,김휘동,이채언 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objective : For the purpose of preparing the fundamental data and assessing the status of exposure level of chemical substances and physical agents. Methods and Material : Such as noise, two types of dust, four types of metals, seventeen types of organic solvents, and four types of other materials classified by specific chemical substances in 21 metal product plating factories classified by 28 processes. The author determined exposure level on those hazardous materials from Jan. to Dec. 2001. Results : The results were as follows: 1. The exposure level for noise was exceeded to Threshold Limit Value(TLV) in the process of 6 cases of Machining, 5 and 4 cases of pre and post-buffing, and 6 cases of waterdrop-removing, the mean noise level of all of processes was not exceeded to compliance level. 2. The exposure level for dust was not exceeded to TLV at all. 3. The exposure level for Chromium(Cr) was exceeded to TLV in Chromium plating process, metal exposure level including Zinc(Zn), Manganese(Mn), and Lead(Pb) was not exceeded to TLV. 4. The exposure level of toluene in case of organic solvents was exceeded to TLV in 1 case of finishing/cleaning, coating/developing process, respectively. 5. The exposure level of four types of other materials classified by specific chemical substances were not exceeded to TLV. 6. The exposure level for dust and metal including Zn, Mn, and Pb was decreased in comparison with two results of air monitoring performed. There was no difference of the exposure level for Cr, noise, and four types of other materials classified by specific chemical substances, and the exposure level for organic solvents was slightly increased. 7. The exposure level for noise in factories employing more than 21 workers was higher than that for noise in foadtories employing less than 20 workers. The more workers, the lower exposure level in metal including Zn, Mn. The exposure level for Cr was increasing in factories employing more than 51 workers, and the more workers the lower exposure level in organic solvents. Conclusion : According to above results, this study suggests positive work environment managements in processes exceeding exposure limit value as well as continuously consecutive work environment management in processes not exceeding exposure limit value and revealing no chronological difference of exposure level should be needed.

154kV 변전소의 전자계 및 유도전압 계산에 관한 연구

문채주,장영학,최창혁 木浦大學校 工業技術硏究所 1999 工業技術硏究誌 Vol.9 No.-

This paper is to analyse electromagnetic fields on a 154kV substation system and induced voltages on the substation fence when the network is operating in a normal condition or a fault condition in which one phase is shorted with the ground wire using HIFREQ software. Also, the changing trend of scalar potential and electromagnetic fields that are changed in accordance with the value of resistivity and relative permeability of ground are showed and discussed. A finding of the study is that the scalar potential and electro-magnetic fields are raised near the tower, and the values of electric field on the comer of substation fence and at the edge of the ground grid are higher than other locations. And the trends of electric fields under normal condition and fault condition are similar to each other, the trends of magnetic fields are showed the peak value at the inflow point of current. The induced currents of substation fence have the peak value at the bottom outside of transmission line under normal condition and at the bottom of fault line under fault condition.

림프절병증 환자에서 Bartonella henselae와 Bartonella quintana에 대한 항체 양성률

채민병,이지영,곽이경,박성학,임희정,박상우,정문현,김미경,강재승 대한감염학회 2002 감염 Vol.34 No.5

계육 Petty의 저장중 항산화에 미치는 녹차분말의 영향

조재민,문영락 忠州大學校 2007 한국교통대학교 논문집 Vol.42 No.-

The present study was conducted to know the antioxidative effect of Green tea on the lipid in chicken patties. Green tea is known to have diverse physiological functions including cardiotonic function, diuretic function, detoxicating function, sterilization function, antiphlogistic function, and the suppressive effect of food poising. Accordingly, the addition of Green tea powder is mostly appropriate for being used to processed food. With a view to project the storage stability and the storage life prolongation of chicken meat, we gained the following results after reviewing the storage stability and the effect on the antioxidant according to the addition of Green tea powder during storage of chicken patties for 15days at 5℃ or -5℃. 1. The Effect of the antioxidant on the lipid of chicken patties was increased according to the addition of Green tea powder. 2. The Effect of the antioxidant on the lipid of chicken patties was not especially changed in TBA value according to the addition of Green tea powder 1.0% and Na-Nitrite 50ppm, 100ppm, and 150ppm especially. 3. The addition of Green tea powder demonstrated the best effect of suppressing the TBA value at a lower temperature(-5℃)

Hg_(1-x_CD_(x)Te의 陽極酸化에 관한 硏究

문정학,손인호,김영국,채건식 경남대학교 환경문제연구소 1993 환경연구 Vol.15 No.-

The electrochemical property in H_(g)-(x)_Cd_(x)Te(x= 0.198) by anodic oxcidation have been studied in the standard aqueous solutions(pH=6, 9, 12) of ethylene glycol(90%) and H₂O-KOH(10%). At range of potential -0.1V ~ + 1.2V, 3 oxcidation peaks appeared. The rich residue Hg of HCT surface was related to oxcidation process of depleting Hg²+ ion in aqueous solution. Most of oxcidation materials were considered TeO₃ HTeO₃ HHgO₂, HTeO₂, TeO₂ and very little of Cd(OH)₂. The higher PH degree, the faster oxcidation process.

Dump 소각기에서 CCl_(4) 분해에 대한 수치해석

채종성,엄태인,전영남,문승현 한밭대학교 생산융합기술연구소 2004 생산기반기술연구소 논문집 Vol.4 No.1

A major source of the hazardous waste generated is from chemical industries producing plastics, herbicides, pesticides and chlorinated solvents. All of these processes produce a class of hazardous waste termed the chlorinated hydrocarbons (CHCs), either directly or from undesirable side reactions. In this study, the destruction characteristics of hazardous waste through incineration is investigated by the development of a reliable computer program. Especially a nonequilibrium combustion model was used to describe the effect of the chemical kinetics due to the flame inhibition characteristics of CCl_(4) which was used as the surrogate of hazardous waste.

통계적 기법을 이용한 BUS需要推定에 관한 연구 : 浦項市 住居開發地域을 中心으로

임채문,박문하,박영환 대구대학교 과학기술연구소 1997 科學技術硏究 Vol.4 No.3

This research is based on the transits of bus movement in the residence area around the center of Pohang city to estimate the future bus traffic volumes individual transits of each area that is those of living area, non living area, the number of students, and workers are investigated, 22 out of 25 zones, which intend to be more residential are selectedby the motheds of cluster analysis, stepwise regression and multi regression, in order to find out the relation between the bus traffic volume and the individual transit the analysis of the relation, which put the value of the zone transit on the formula as a variable, can formulate its influence on the bus traffic volume. if this analysis is applied to the future residential development area if will contribute to calculation of the number of bus users and the decision of allocation interval of buses and the number of bus lines