활성탄소의 산 , 염기 특성에 관한 연구

김기동,박수진,이재락,송해영 ( Ki Dong Kim,Soo Jin Park,Jae Rock Lee,Hae Young Song ) 한국공업화학회 1997 한국공업화학회 연구논문 초록집 Vol.1997 No.0

LC/MS법 및 LC/UVD(EPA-631)를 이용한 수계 중 Benomyl의 분석법 평가

김기동,최원규,서용찬,박병황,최혜경,Kim, Kee D.,Choi, Won Gyu,Seo, Yong Chan,Park, Byung Hwang,Choi, Hye Kyung 대한화학회 2001 대한화학회지 Vol.45 No.1

내분비계 장애물질 중의 하나인 농약 benomyl의 환경잔류실태를 조사하기 위해 수질중의 benomyl 농도를 정량 하였다. 일반적으로 benomyl은 가수분해하여 carbendazim으로 변하며 본 분석법은 carbendazim을 정량 하는 간접법이다. 수질중의 잔여 benomyl은 가수분??후 적절한 용매로 추출하여 농축, 정제되었다. 농축된 시료의 carbendazim 농도를 LC/MS (TOF)로 분석하였으며 그 결과 방해물질에 의해 발생할 수 있는 오차를 제거할 수 있었다. 검출한계는 LC/UVD법(EPA-631)에 비하여 약 1,600배 낮았으며 spike의 회수율도 약 80~118%로 양호하였다. Benomyl, one of the known endocrine disrupting chemicals, was analyzed to understand the its fate in water. Benomyl analysis process in water sample include the following sequential steps. Hydrolysis of benomyl into carbendazim, solvent extraction, concentration, and the concentration of final carbendazim solution was determined by LC/MS (TOF). Recoveries of the spiked samples were good with the range of 80.6 to 118.6% and the MDL was 1,600 times lower than that of LC/UVD method. The use of LC/MS (TOF) successfully eliminated the positive error incurred by interferencing materials in the matrix.

Design of Prestressed W-Shape Beams with a Separated Prestressing Cover Plate

김기동,안효일,한기장,Dong Seong Kim 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.2

Prestressed steel beams with a prestressing cover plate (PBCP), which are expected to overcome the limitations of prestressed steel girders using tendons, were investigated in this study. Experiments and fi nite element analyses (FEA) were performed to present a design procedure. The maximum compressive force according to fl ange slenderness, which could be applied to steel beams subjected to bending moment due to ultimate load, was investigated for rolled W-shape beams. The fl exural capacity and elastic fl exural stiff ness of steel beams could be signifi cantly increased by using a cover plate attached at a fi xed distance from the bottom fl ange of a steel beam as a prestressing member. A PBCP with W920 × 1377 could achieve a maximum span of 72 m for a two-lane, single-span composite bridge with fi ve girders when the span-to-depth ratio is limited to around 38.0, whereas an ordinary composite beam with the same W-shape section, having a span-to-depth ratio of 36.0, could achieve a maximum span of around 50 m. The limitations of maximum bridge length, minimum steel amount and maximum span-to-depth ratio that rolled fl exural members can achieve were able to be effi ciently overcome by using the PBCP. The span-to-depth ratio of PBCPs was about 2.08 times larger on average than that of plate girders for bridge lengths of 50 m to 72 m. The PBCP could employ a smaller steel volume than plate girders for the same span-to-depth ratio. Therefore, it could be seen that the PBCP could be an alternative to plate girders for the limited span-to-depth ratio and even for the cost effi ciency.

16종 다용한약재의 산지별 As, Cd, Pb, Co, Cr 농도 및 특성고찰 -한국과 중국산의 평균농도, 최소-최대농도와 법적 허용농도초과비율을 중심으로-

김기동,박해모,서용찬,이선동,Kim, Kee-Dong,Park, Hae-Mo,Seo, Yong-Chan,Lee, Sun-Dong 대한예방한의학회 2012 대한예방한의학회지 Vol.16 No.3

Objective : Average, lowest, highest concentration and exceeding value of legal allowance of As, Cd, Pb, Co, Cr in frequently using 16 oriental herbal medicines in korea(Astragali Radix, Ginseng, Citri Unshii Pericarpium, Aurantii Fructus Immaturus, Angelicae Gigantis Radix, Cnidii Rhizoma, Paeoniae Radix, Rehmanniae Radix Preparata, Zingiberis Rhizoma Crudus, Zizyphi Fructus, Atractylodis Rhizoma Alba, Hoelen, Dioscoreae Rhizoma, Corni Fructus, Schisandrae Fructus, Lycii Fructus) was evaluated according to their origines (korea, china) and property was also discussed according to the medicinally active part and individuals regardless origines. Method : Korean and Chinese herbal medicines were evenly sampled from corresponding country nationwide. Pre-treatment was executed according to the KFDA(Korea Food and Drug Administration) regulation and analysis was performed according to the Korean Environmental Analysis QA/QC. Result : Not much difference was observed according to their origines. However, lowest, highest and percent exceeding value of legal allowance was showed some consistent differences according to the medicinally active part and individuals. Co and Cr was can not be evaluated since their legal regulation was not established yet. Conclusion : The average concentration of As, Cd, Pb, Co, Cr in frequently using 16 oriental herbal medicines in korea showed no noticeable difference according to their origines. Regardless the origin, some consistent differences were observed according to the individuals and medicinally active parts.

LC/MS(TOF)를 이용한 토양 중 Benomyl의 농도 분석

김기동,서용찬,최원규,Kim, Kee D.,Seo, Yong Chan,Choi, Won Gyu 대한화학회 2001 대한화학회지 Vol.45 No.2

차량 속도-시간 이력을 이용한 고규격 종방향 연성 배리어 설계

김기동,고만기,김동성,주재웅,장대영,Kim. Kee Dong,Ko. Man Gi,Kim. Dong Seong,Joo. Jae Woong,Jang. Dae Young 한국방재학회 2012 한국방재학회논문집 Vol.12 No.3

기존의 국내/외 충돌조건보다 상향된 충돌조건(900 kg의 승용차가 120 km/h의 속도와 <TEX>$20^{\circ}$</TEX>의 각도로 충돌하는 조건과 14 ton의 트럭이 85 km/h의 속도와 <TEX>$15^{\circ}$</TEX>의 각도로 충돌하는 조건, 그리고 13 ton의 버스가 90 km/h의 속도와 <TEX>$15^{\circ}$</TEX>의 각도로 충돌하는 조건)에 대하여 효과적으로 종방향 연성 배리어를 개발하기 위해서 차량 속도-시간 이력이 이용되었다. 차량 종방향 속도-시간이력 곡선과 횡방향 속도-시간 이력 곡선의 기울기가 충돌초기의 전반 부분에서 가능한 증가되고 THIV 발생시간 전후의 시간구간인 후반 부분에서 감소될 수 있도록 설계가 이루어 질 때 연성 배리어의 설계를 주로 좌우하는 THIV가 효과적으로 감소될 수 있었다. 이러한 이상적인 차량 속도-시간 이력을 발생시킬 가능성이 있는 다양한 예비설계가 수행되었고 LS-DYNA 프로그램을 이용한 유한요소해석을 통하여 적합한 설계가 결정되었다. 최종설계에 대한 실물차량 충돌시험을 통하여 고규격 종방향 연성 배리어의 개발이 성공적으로 이루어졌다. Vehicle velocity-time histories were used to develop efficiently longitudinal a flexible barrier for the impact condition which is more severe than the existing domestic and foreign impact conditions(a passenger car of 900kg impacts with the velocity of 120km/h and the angle of <TEX>$20^{\circ}$</TEX>, a truck of 14ton impacts with the velocity of 85km/h and the angle of <TEX>$15^{\circ}$</TEX>, and a bus of 13 ton impacts with the velocity of 90 km/h and the angle of <TEX>$15^{\circ}$</TEX>). When the design of longitudinal barriers was implemented such that the initial slopes of vehicle longitudinal and transverse velocity-time history curves were increased as far as possible and the post slopes for the fore and hind portions of the time at which THIV was determined were reduced, THIV which mainly governed the design of longitudinal barriers could be effectively reduced. Various preliminary designs, which had the possibility of producing the above ideal vehicle velocity-time histories, were conducted and the final design of a longitudinal flexible barrier was determined by finite element analyses using LS-DYNA program. The development of a high-performance longitudinal flexible barrier was successfully completed by conducting full scale vehicle crash tests for the final design.

다섯 가지 다용한약처방의 전탕 전후 유해 중금속 이행률 조사

김기동,Kim, Kee Dong 대한예방한의학회 2015 대한예방한의학회지 Vol.19 No.3

Objective : Five most generally adopting basic oriental prescriptions (yookmijihwangtang, ojeoksan, sipjeondaebotang, samultang, bojoongikgitang) samples were collected from 10 oriental hospitals nationwide and the transferring ratio to aqueous phase (TRAP) were calculated. Method : The samples are grounded evenly and the decocted at $120^{\circ}C$ for 12 min on hot plate and then filtered. The concentrations of As, Cd, Co, Cr and Pb in before and after decoction were measure by ICP/MS and the TRAPs were calculated. Results : The concentrations of As, Cr and Pb in the ground samples before decoction were all below criteria level, and TRAP values were also very low (<10%). For Cd, although some ground samples before decoction showed relatively high concentration level compare to the criteria level, because of their low TRAP (~3%), the actual concentrations in the decoction were quite low compare the criteria level. The Co's concentrations in the ground samples before decoction were all relatively low level. However, the TRAP of Co was astonishingly high value of around 40% average. Conclusion : The toxic heavy metal concentrations in the decoction were very low compare to the criteria level. The TRAPs are less than <10% except Co. The toxic heavy metals in the prescriptions are mainly remained in the residue and the only very small fraction may transferred to the decoctions. Therefore the toxicity of the oriental herbal medicine about the toxic heavy metal may be overstressed. The Co's TRAP turned out to be quite high value (40% average). Since the criteria level wes not established yet, the safety of decoctions according to Co was not fully confirmed.

Plasma Display Panel용 기판 유리용융체의 내화물 침식

김기동,정현수,김효광,Kim, Ki-Dong,Jung, Hyun-Su,Kim, Hyo-Kwang 한국세라믹학회 2007 한국세라믹학회지 Vol.44 No.1

For self-developed alkali-alkaline earth-silicate and commercial glass melts for plasma display panel substrate, the corrosion behavior of fused casting refractory consisting of $Al_2O_3-ZrO_2-SiO_2$ was examined at the temperature corresponding to $10^2\;dPa{\cdot}s$ of melt viscosity by static finger methode. The corroded refractory specimens showed a typical concave shape due to interfacial convection of melts at their flux line. However, the corrosion thickness by commercial glass melts was $6\sim10$ times comparing to that by the self?developed melts. From the view point of the glass composition and the role of alkaline earth in glass network, it was discussed the effect of alkali/alkaline earth diffusion and temperature on the refractory corrosion.

성토부 지주 보강과 SB3-B 연성배리어의 개발

김기동,박경룡,고만기,Kim,Kee Dong,Park,Kyoung Yong,Ko,Man Gi 한국방재학회 2014 한국방재학회논문집 Vol.14 No.1

2012년 11월에 개정된 `도로안전시설 설치 및 관리 지침`은 노측용 종방향 배리어에 대한 표준 성능시험을 평지부 대신에 성토부에서 시행하도록 규정하고 있다. 또한 성토부에 설치되는 지주의 현장지지력이 시험장지지력의 90% 이상이 되도록 하고 있다. 본 연구에서는 성토부에 설치되는 지주의 횡방향 지지력을 보강할 수 있는 다양한 지주 보강방안이 조사되었다. 보강되지 않은 일반지주(매입깊이 1.4 m)에 비하여 지주 매입깊이를 1.7 m로 증가시키는 경우에 33%의 지지력 증가가 나타났다. 다양한 형태의 보강판중에서 단면적과 지주를 감싸는 보강판의 절곡길이가 작은 경우에 시공성이 우수하였고 약 70%의 지지력 증가가 발생하였다. 그리고 Bracing을 사용하는 방안은 약 78%의 지지력 증가를 낳았다. 평지부 시험을 통과한 SB5-B등급 연성배리어의 구성요소와 동일한 구성요소를 적용하는 SB3-B등급 연성배리어가 개발되었다. SB3-B등급 충돌조건에 적절한 지주간격과 성토부 지주의 보강방안이 다양한 컴퓨터 시뮬레이션을 통하여 결정되었고 실물충돌시험을 통하여 최종성능이 검증되었다. The guidelines for the installation and management of roadway safety features, revised in November 2012, is regulating the standard performance test for roadside longitudinal barriers to be implemented on an embankment instead of a flatland. Furthermore, the post installed on an embankment should have the resisting force of a construction site higher than 90% of that of a test site. In this study, a variety of post reinforcement methods were investigated in order to strengthen the lateral resisting force of the post installed on an embankment. When increasing the post embedded depth to 1.7 m from a non-reinforced post with an embedded depth of 1.4 m, an increase of 33% in resisting force occurred. For the case of having a small cross section and a small flexure length of the reinforcing plate wrapping a post, out of various forms of reinforcing plates, the constructability was excellent and the resisting force increased by 70% approximately. For the reinforcement method using a bracing member, the increase of approximate 78% occurred in resisting force. A SB3-B flexible barrier that uses the same as the components of the SB5-B flexible barrier which passed the flatland performance test was developed. Post spacing and post reinforcement methods appropriate for SB3-B impact conditions were determined by various computer simulations, and the final performance was verified through full-scale vehicle crash tests.

0-1 혼합정수계획법을 이용한 LCD 패널 절단 문제 최적화

김기동,박현지,심윤섭,전태보,Kim, Kidong,Park, Hyeon Ji,Shim, Yun-Seop,Jeon, Tae Bo 한국센서학회 2017 센서학회지 Vol.26 No.4

LCD(Liquid Crystal Display) panel cutting problem is a sort of two dimensional cutting stock problem. A cutting stock problem is problem that it minimizes the loss of the stock when a stock is cut into various parts. In the most research of the two dimensional cutting stock problem, it is supposed that the relative angle of a stock and parts is not important. Usually the angle is regarded as horizontal or perpendicular. In the manufacturing of polarizing film of LCD, the relative angle should be maintained at some specific angle because of the physical and/or chemical characteristics of raw material. We propose a mathematical model for solving this problem, a two-dimensional non-Guillotine cutting stock problem that is restricted by an arranged angle. Some example problems are solved by the C++ program using ILOG CPLEX classes. We could get the verification and validation of the suggested model based on the solutions.