http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
흡입챔버 내 Didecyldimethyl Ammonium Chloride 및 Ethylene Glycol 혼합물질 분석법 연구
이두희 ( Doo Hee Lee ),이진선 ( Jin Seon Lee ),권정택 ( Jung Taek Kwon ),권도영 ( Do Young Kwon ),김은지 ( Eun Ji Kim ),박상아 ( Sang Ah Park ),이혜리 ( Hye Ri Lee ),김현미 ( Hyun Mi Kim ),이원석 ( Won Seok Lee ) 한국환경분석학회 2015 환경분석과 독성보건 Vol.18 No.2
This study evaluated analytical methods for the mixture of ethylene glycol (EG) and didecyldimethyl ammonium chloride (DDAC), which are used as the main components of deodorants and biocides. EG and DDAC were nebulized in aerosol into inhalation chambers. For absorbents of EG and DDAC, XAD-7 OVS resin and glass fiber (GF) filters were used, respectively. Instrumental analysis was conducted with gas chromatography/ flame ionization detector (GC/FID) for EG and high performance liquid chromatography with triple-quadrupole mass spectrometer (LC/MS/MS) for DDAC. The method detection limit (MDL) and the limit of quantitation (LOQ) were 24 μg/m3 and 77 μg/m3 for EG, and 13 ng/m3 and 41 ng/m3 for DDAC. The recovery rates ranged from 100.7% to 105.5% for EG, and 97.4% to 98.9% for DDAC. The relative standard deviation (RSD) of EG and DDAC ranged less than 5.72%. Daily monitoring was also conducted at the concentration of 0.2% for 7 days. The results showed that the mean values ranged from 0.728 mg/m3 to 0.739 mg/m3 and the overall accuracy was 11.9% to 16.2%.
Yeung Bae Jin,Woo H. Kim,Kwang Il Park,Sung Joong Lee,Suk Kim,Hu-Jang Lee 한국예방수의학회 2023 예방수의학회지 Vol.47 No.4
This study was conducted to reset the maximum residue limit (MRL) for didecyldimethylammonium chloride (DDAC) in broiler chickens. The disinfectant containing DDAC (10%, w/w) was diluted 160 times and evenly sprayed on the bodies of twenty-four broiler chickens at a rate of 15 mL per day per bird for 7 days. After the disinfectant treatment, tissue samples were collected from six broiler chickens at 0.25, 1, 3 and 5 days, respectively. Residual DDAC concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 2.0~10.0 μg/kg), recoveries (86.9~118.6%), and coefficient of variations (<19.98%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In all tissues except for liver, DDAC was detected more than LOQ at 5 days after the disinfectant treatment. In liver tissues, DDAC was detected more than LOQ at 3 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal period of DDAC in poultry tissues was established to 26 days. In conclusion, the developed analytical method is sensitive and reliable for detecting DDAC in poultry tissues. When DDAC disinfectant is sprayed on a poultry house in the presence of broiler chickens, it is necessary to keep the disinfectant from contacting the body of the livestock.
Sensitivity Correlations of Electrical Vehicle
Jeong-Ick Lee(이정익) 한국생산제조학회 2009 한국생산제조학회지 Vol.18 No.4
Generally, finite element models used in structural analysis have some uncertainties of the geometric dimensions, applied loads and boundary conditions, as well as in material properties due to the manufacturability of aluminum intensive body. Therefore, it is very important to refine or update a finite element model by correlating it with dynamic and static tests. The structural optimization problems of automotive body are considered for mechanical structures with initial stiffness due to preloading and in operation condition or manufacturing. As the mean compliance and deflection under preloading are chosen as the objective function and constraints, their sensitivities must be derived. The optimization problem is iteratively solved by a sequential convex approximation method in the commercial software. The design variables are corrected by the strain energy scale factor in the element levels. This paper presents an updated method based on the sensitivities of structural responses and the residual error vectors between experimental and simulation models.