가정용 살충제 중 모기 살충제 제품의 살충성분 함량 및 휘산율 조사

이민진(Minjin Lee),이채홍(Chaehong Lee),이지은(Jieun Lee),이정현(Junghyun Lee),탁준형(Junhyung Tak) 환경독성보건학회 2021 한국독성학회 심포지움 및 학술발표회 Vol.2021 No.5

국내에 판매되는 모기 살충제 제품의 제형은 에어로솔, 액체전자모기향, 매트전자모기향, 모기향, 걸이형, 스티커/팔찌 형태로 확인되었다. 액체 및 매트 전자모기향은 즉효성 제품인 에어로솔 제형과는 달리 일정 시간(기간) 동안 꾸준히 효력을 발휘하는 제형이다. 그러나 현재까지 실제 제품이 주장하는 기간 동안 지속적으로 효력이 발휘되는지에 대한 효능시험의 확인이 이루어지지 않고 있다. 향후 활용을 위한 레퍼런스 구축의 목적으로 제품의 휘산시간(일자)에 따른 살충성분 방출량 곡선 정보 확보가 필요한 실정이다. 또한 살충제 휘산율 평가를 통해 제품 표시 및 광고 내용에 대해 실험을 통한 정량적 확인 및 관리가 가능할 것으로 보인다. 본 연구에서는 휘산시간(일자) 별 살충제 주성분 잔량 분석을 시행하여 살충 효능 유지 정도를 분석적 관점에서 확인하였다. 액체 및 매트 전자모기향에 사용되는 살충성분 d,d-시스/트란스프랄레트린, d-시스/트란스알레트린, 메토플루트린에 대해 휘산 전 제품 자체의 살충성분 함량 조사와 일정한 시간으로 ( 0 ~ 21 )시간 또는 ( 0 ~ 45 )일 휘산 시켰을 경우 제품에 잔류하고 있는 살충성분 잔류량을 조사하였다. 각 제품에 대한 주성분 함량 분석 및 휘산성 평가를 통해 향후 각 살생물제품 개발 업체 및 제조 업체의 원료 및 제품 품질관리 및 신규 제품 개발을 위한 기초자료로 활용이 가능할 것으로 사료된다.

좀벌레 방제제 제품 중 엠펜트린 잔류량 실태조사

이민진(Minjin Lee),이채홍(Chaehong Lee),이지은(Jieun Lee),이정현(Junghyun Lee),탁준형(Junhyung Tak) 환경독성보건학회 2021 한국독성학회 심포지움 및 학술발표회 Vol.2021 No.5

오래전부터 좀벌레 방제를 위해 나프탈렌을 사용해왔으나, 나프탈렌의 강한 향취로 인해 사용에 부담이 크며, 이를 대체하는 목적으로 무향, 무취의 엠펜트린을 주성분으로 한 좀벌레 방제제 사용이 대세가 되었다. 좀벌레는 질병을 매개하지는 않으나, 단순히 의류의 손상을 가하는 등의 경제적 피해만을 주는 해충으로 분류되어 좀벌레 방제제는 지금까지 공산품으로 유통되어 왔으며, 이들 제품에 대한 함량 기준 및 효능 기준이 전무한 상황이었다. 그러나 「생화화학제품 및 살생물제의 안전관리에 관한 법률」(이하 ‘화학제품안전법’)이 2019년 1월 1일 시행되면서 살생물제로 편입되어 해당 효능물질 및 제품에 대한 인허가 기준을 정립할 필요성이 발생하게 되었다. 현재 방충 효능을 나타낼 수 있는 엠펜트린의 기준이 없어 정확한 사용량 확인이 필요한 실정이다. 본 연구에서는 좀벌레 방제제로 사용되는 엠펜트린의 독성자료 개발을 위한 기초자료로 제품 중 엠펜트린의 함유량 실태조사와 최대 6개월까지 휘산 후 제품 중 엠펜트린의 잔류량을 확인하고자 한다. 국내에서 판매중인 좀벌레 방제제 29개 제품에 대해 엠펜트린 분석결과 20개 제품에서 엠펜트린이 검출되었으며, 검출된 제품에 대해 제품의 용도에 맞게 옷장과 서랍장에서 1개월, 2개월, 3개월, 4개월, 6개월 휘산시킨 후 잔류하는 엠펜트린 함량시험을 진행하여 휘산율을 확인하였다.

Tubular Superstructures Composed of α-Fe₂O₃ Nanoparticles from Pyrolysis of Metal–Organic Frameworks in a Confined Space: Effect on Morphology, Particle Size, and Magnetic Properties

Lee, Junhyung,Kwak, Seung-Yeop The American Chemical Society 2017 CRYSTAL GROWTH AND DESIGN Vol.17 No.9

<P>While preparation of metal oxide from metal organic frameworks (MOFs) has been widely studied, crystal growth via thermal decomposition of MOFs in a confined space is rarely investigated. We demonstrate a confinement effect on the crystal growth via pyrolysis of MOFs at high temperature. Iron containing MOF (Fe-MIL-88A) was calcined inside a SiO2. The crystalline phase, particle size, morphology, and magnetic properties of the synthesized iron oxide were characterized; alpha-Fe2O3 tubular structures that consisted of nanoparticles (around 10 nm) were observed. Studies of the magnetic properties show enhanced magnetization with superparamagnetic behavior. These results indicate that space confinement during the thermal treatment in air at high temperature allows the synthesis of small nanoparticles and the preservation of initial morphology of MOF precursors, which cannot be obtained via heating of MOFs without shell under identical conditions.</P>

Reliability and Validity of the Korean Version of the Brief Resilience Scale

Junhyung Kim,Hyun-Ghang Jeong,Moon‑Soo Lee,Seung-Hoon Lee,Sang-Won Jeon,Changsu Han 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.4

Objective: To translate the Brief Resilience Scale into Korean and evaluate its reliability and validity. Methods: To investigate the factor structure of the Brief Resilience Scale, we examined a two-factor model comprising positively and negatively worded items. Congruent and divergent validity of the Brief Resilience Scale were investigated using correlation analysis between the Brief Resilience Scale and resilience, depression, and perceived stress. By conducting an analysis of variance among groups classified by suicidality (no suicidality, only suicidal ideation, and suicidal ideation or suicidal plan groups), we evaluated how well the Brief Resilience Scale could detect people with a high risk of suicide. Results: Confirmatory factor analysis results supported the construct validity of the Brief Resilience Scale using a two-factor model. Cronbach’s alpha (0.91) and McDonald’s omega (0.91) scores indicated high internal consistency. Correlation analysis showed that the Brief Resilience Scale scores were strongly associated with a questionnaire evaluating resilience, depression, and perceived stress. Analysis of variance and post-hoc tests showed that he Brief Resilience Scale scores were highest in the no suicidality group (p < 0.001). Conclusion: The Korean version of the Brief Resilience Scale is a valid and reliable instrument for evaluating resilience as the capacity to recover from adversity and endure obstacles or stress. This study also provides important evidence regarding the sensitivity of the Brief Resilience Scale to suicidal risk.

Effects of hot-melt extruded nano-copper on the Cu bioavailability and growth of broiler chickens

( Junhyung Lee ),( Abdolreza Hosseindoust ),( Minju Kim ),( Kwangyeol Kim ),( Taegyun Kim ),( Joseph Moturi ),( Byungjo Chae ) 한국축산학회(구 한국동물자원과학회) 2021 한국축산학회지 Vol.63 No.2

This study was aimed to investigate the Cu bioavailability, growth response, digestibility of nutrients, and blood metabolites of broiler chicks fed CuSO₄ in nano or common forms. A total of 720 broiler chickens were distributed between eight treatments according to a completely randomized design. There were 8 treatments and 6 replicates in each treatment with 15 birds/replicate. The treatments were divided into common copper sulfate at the doses of 16 ppm, 40 ppm, 80 ppm, and 120 ppm (INO) and hot-melt extruded copper sulfate at the doses of 16 ppm, 40 ppm, 80 ppm, and 120 ppm (HME-Cu). The experiment was operated for 35 days in 2 phases (phase 1, d 0 to 14; and phase 2, d 15 to 35). No significant differences were shown in growth performance, feed intake, FCR, and nutrient digestibility among the treatments. The concentration of Cu in the serum was increased in the HME-Cu broilers compared with the INO broilers at phase 2. A linear increase was observed in the concentration of Cu in the liver in broilers fed INO diets, however, no significant differences were observed by the supplementation of HME-Cu levels. The linear increase was detected in the content of Cu in excreta in the INO and HME-Cu treatments by increasing the dietary Cu content. The HME-Cu treatments showed a lower Cu concentration in the excreta compared with the INO treatments. The higher bioavailability of Cu in HME form can decrease the recommended dose of Cu in broiler diets.

Nonlinear Identification of Electronic Brake Pedal Behavior Using Hybrid GMDH and Genetic Algorithm in Brake-By-Wire System

Junhyung Bae,Seonghun Lee,Dong-Hwan Shin,Jaeseung Hong,Jaeseong Lee,Jong-Hae Kim 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.3

In this paper, we represent a nonlinear identification of electronic brake pedal behavior in the brake-by-wire (BBW) system based on hybrid group method of data handling (GMDH) and genetic algorithm (GA). A GMDH is a kind of multi-layer network with a structure that is determined through training and which can express nonlinear dynamics as a mathematical model. The GA is used in the GMDH, enabling each neuron to search for its optimal set of connections with the preceding layer. The results obtained with this hybrid approach were compared with different nonlinear system identification methods. The experimental results showed that the hybrid approach performs better than the other methods in terms of root mean square error (RMSE) and correlation coefficients. The hybrid GMDH/GA approach was effective for modeling and predicting the brake pedal system under random braking conditions.

Development and comparison of two H5N8 influenza A vaccine candidate strains

Lee, Mi-Seon,Jang, Eun Young,Cho, Junhyung,Kim, Kisoon,Lee, Chan Hee,Yi, Hwajung Springer-Verlag 2019 Archives of virology Vol.164 No.1

Effects of hot melt extrusion processed nano-iron on growth performance, blood composition, and iron bioavailability in weanling pigs

( Junhyung Lee ),( Abdolreza Hosseindoust ),( Minju Kim ),( Kwangyeol Kim ),( Yohan Choi ),( Joseph Moturi ),( Changhyun Song ),( Songyi Lee ),( Hyunjong Cho ),( Byungjo Chae ) 한국축산학회 2019 한국축산학회지 Vol.61 No.4

This study was conducted to investigate the effects of hot melt extrusion (HME) nano-iron as an alternative for the common ferrous sulfate on iron (Fe) bioavailability, growth performance, nutrient digestibility, intestinal morphology, and intestinal microbiota of weanling pigs. A total of 200 piglets (Landrace × Yorkshire × Duroc) were randomly allotted to seven treatments on the basis of initial body weight (BW) and sex. Treatments were the INO100 (100 ppm Fe as FeSO₄), HME-Fe levels (50, 75, and 100 ppm nano-Fe as FeSO₄). ORG100 (100 ppm Fe as iron methionine). In phase 1, the HME50 pigs showed the lowest Fe content in feed and feces. Plasma Fe concentration was increased in HME100 and ORG100 pigs. In phase 2, there were significantly lower concentration of Fe in feed and feces of HME50 pigs (p < 0.01). A lower Fe concentration in the plasma and liver were observed in HME50 pigs compared with HME100 pigs. Concentration of red blood cell (RBC) was the lowest (p < 0.01) for HME50 pigs. During phase 2, the HME100, HME75, and ORG100 pigs showed a higher RBC and hemoglobin values compared with HME50 pigs. Digestibility of gross energy (GE) and crude protein (CP) were significantly higher in HME100 pigs compared with HME50 pigs. There was an increased (p < 0.01) villus height in the duodenum and jejunum of HME100 pigs compared with HME50 pigs. It is concluded that dietary Fe does not improve growth performance of weanling pigs; however, increasing the dietary iron concentration in weanling piglets increased the RBC and hemoglobin. In addition, the potential ability of HME to be used at a lower level (HME75) was observed.

다양한 파쇄 유체별 파쇄압력, 투과도 증진 및 균열전파에 관한 실험적 연구

최준형(JunHyung Choi),이현석(Hyun Suk Lee),김도영(Do Young Kim),남정헌(Jung Hun Nam),이대성(Dae Sung Lee) 한국암반공학회 2021 터널과지하공간 Vol.31 No.1

치밀 저류층의 투과도 증진을 위해 개발된 수압파쇄 기술은 셰일가스와 같은 비전통자원과 심부지열 개발에 필수적인 기술 중 하나이다. 파쇄형태가 단순하고 파쇄효율이 좋지 않은 수압파쇄를 개선하기 위해 다양한 파쇄유체를 이용한 실험적 연구가 진행되었다. 물, N₂, CO₂ 가스를 파쇄유체로 사용하여 치밀 암석에 대한 파쇄형태와 효율성을 분석하였다. 파쇄유체로 물을 일정 주입속도로 주입한 경우 순간적으로 압력이 상승하여 파쇄가 발생하였으나, 파쇄유체로 가스를 주입한 경우 서서히 압력이 증가되면서 물보다 낮은 파쇄압력을 보였다. 3D 단층촬영 기법을 이용하여 물과 가스 주입으로 생성된 균열을 관찰한 결과는 기존 공극부피 대비 파쇄 자극부피가 각각 5.71%(물), 12.72%(N₂), 43.82%(CO₂) 증가되었다. 또한 파쇄유체의 파쇄 효율성을 검정하기 위한 파쇄 전후 투과도 변화 실험에서는 가스 파쇄에 의해 증가되는 투과도 증가 값이 물을 이용한 파쇄보다 훨씬 높게 측정되었다. 파쇄 이후 인공균열의 생성과 주변응력에 의해 다시 균열이 닫히는 현상을 고려하여 생성된 인공균열에 구속압을 단계별로 증가시켜 투과도 변화를 측정하였다. 구속압이 2MPa에서 10MPa로 증가시켰을 경우 초기 투과도 대비 각각 89%(N₂), 50%(CO₂) 감소하였다. 본 연구는 가스파쇄기술이 수압파쇄보다 투과도 증진 효과가 크고 이후 주변 응력에 의한 투과도 감소가 적은 것으로 나타났다. The hydraulic fracturing developed to improve permeability of tight reservoir is one of key stimulation technologies for developing unconventional resources such as shale gas and deep geothermal energy. The experimental study was conducted to improve disadvantage of hydraulic fracturing which has simple fracture pattern and poor fracturing efficiency. The fracturing experiments was conducted for tight rock using various fracturing fluids, water, N₂, and CO₂ and the created fracture pattern and fracturing efficiency was analyzed depending on fracturing fluids. The borehole pressure increased rapidly and then made fractures for hydraulic fracturing with constant injection rate, however, gas fracturing shows slowly increased pressure and less fracture pressure. The 3D tomography technic was used to generate images of induced fracture using hydraulic and gas fracturing. The stimulated reservoir volume (SRV) was estimated increment of 5.71% (water), 12.72% (N₂), and 43.82% (CO₂) respectively compared to initial pore volume. In addition, permeability measurement was carried out before and after fracturing experiments and the enhanced permeability by gas fracturing showed higher than hydraulic fracturing. The fracture conductivity was measured by increasing confining stress to consider newly creating fracture and closing induced fracture right after fracturing. When the confining stress was increased from 2MPa to 10MPa, the initial permeability was decreased by 89% (N₂) and 50% (CO₂) respectively. This study shows that the gas fracturing makes more permeability enhancement and less reduction of induced fracture conductivity than hydraulic fracturing.

차량 운전 특성에 따른 연비성능 시뮬레이션

송준형(Junhyung Song),김덕진(Deokjin Kim),이천환(Chunhwan Lee),이춘범(Chunbeom Lee) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11

This paper discussed conditions of acceleration through a velocity profile of vehicle modeling by using the simulation program in order to analyze the characteristic of fuel efficiency according to the pattern of acceleration and vehicle driving. The experiment was performed under the condition of the slope of acceleration, the change of velocity, and the slope change of velocity. Then, the basic performance of vehicle and the characteristic of driving pattern were analyzed through simulating. Through analyzing simulating results according to the initial change of acceleration, we could see that the amount of fuel consumption was little when the accelerated motion was increased gradually, but the good efficiency was shown when the ability of initial acceleration was better with consideration of fuel consumption per distance, while there are various routes under the condition of reaching the goal velocity in the same time. Through analyzing simulating results according to the driving pattern, we could see that the generating power was lower, but the fuel efficiency was better when the accelerated motion was increased gradually.