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991.
992.
Junghyun Kim Joon Hyuk Suh Hyun-Deok Cho Wonjae Kang Yong Seok Choi 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):420-432
A multi-class, multi-residue analytical method based on LC-MS/MS detection was developed for the screening and confirmation of 28 veterinary drug and metabolite residues in flatfish, shrimp and eel. The chosen veterinary drugs are prohibited or unauthorised compounds in Korea, which were categorised into various chemical classes including nitroimidazoles, benzimidazoles, sulfones, quinolones, macrolides, phenothiazines, pyrethroids and others. To achieve fast and simultaneous extraction of various analytes, a simple and generic liquid extraction procedure using EDTA-ammonium acetate buffer and acetonitrile, without further clean-up steps, was applied to sample preparation. The final extracts were analysed by ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). The method was validated for each compound in each matrix at three different concentrations (5, 10 and 20 ng g–1) in accordance with Codex guidelines (CAC/GL 71-2009). For most compounds, the recoveries were in the range of 60–110%, and precision, expressed as the relative standard deviation (RSD), was in the range of 5–15%. The detection capabilities (CCβs) were below or equal to 5 ng g–1, which indicates that the developed method is sufficient to detect illegal fishery products containing the target compounds above the residue limit (10 ng g–1) of the new regulatory system (Positive List System – PLS). 相似文献
993.
The effective parameters on the diameter of carbon nanotubes (CNTs) by plasma enhanced chemical vapor deposition (PECVD) were presented.Among lots of influential parameters,the effects of the catalytic film thickness and the pretreatment plasma power on the growth of CNTs were investigated.The results show that the size of catalytic islands increases by increasing the thickness of catalytic layer,but the density of CNTs decreases.The pretreatment duration time of 30 s is the optimal condition for growing CNTs with about 50 nm in diameter.By increasing the pretreatment plasma power,the diameter of CNTs decreases gradually.However,the diameter of CNTs does not change drastically from 80 to 120 W.The uniformly grown CNTs with the diameter of 50 nm are obtained at the pretreatment plasma power of 100 W. 相似文献
994.
Sung-Dae Kim Sang-Hwa Baek Tae-Yeob Kang So-Jin Park Chulju Kim Han Seo Ko 《Journal of Mechanical Science and Technology》2012,26(10):3339-3345
Thermal behaviors of combined weapon systems were analyzed by developed computational programs in this study. Also, temperature distributions of the materials of the system were measured according to the experimental conditions. Field tests that reflected the calculated thermal flow characteristics and the measured temperature distributions of the materials were prepared in a large environmental tester for the weapon systems. Boundary conditions of the analysis were the inlet and outlet conditions of the environmental tester and the low temperature limit of ?32°C. The soaking time of the system, including a fuel tank and a battery in the environmental tester, was obtained by the programs developed in this study to carry out the experiment in the predicted conditions. 相似文献
995.
XU Ji-fang ZHANG Jie-yu LI Jian-chao SHENG Min-qi ZENG Tao WAN Kang 《钢铁研究学报(英文版)》2012,(Z2):1141-1144
The deoxidization reaction at the interface between slag and metal is one of the most important reactions in the iron and steel making.The interface reaction and transport characteristics of Molten Ultra-low Carbon Steel with CaO-MgO-Al2O3 slag system under different over potential conditions of the system was studied.The electrochemical reduction mechanism at the interface between the molten slag and molten steel was investigated.The results showed that Chronoamperometry method is very useful for the study of interfacial reaction in the slag-metal system.The current of interfacial reaction decreases approximately linearly with t-1/2,and the diffusion coefficient of oxygen in molten slag calculated by Cottrell equation increased dramatically with over potential.In the open circuit potential,the diffusion coefficient of oxygen in the slag is about 10-8m2/s. 相似文献
996.
997.
998.
Young K. Chung Kyung Y. Chang Hoon S. Park Mi‐Hee Kim Kang‐Min Lee Tae‐Seok Lim Hyung W. Kim 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(2):551-555
Carbamazepine (CBZ) intoxication can be associated with severe toxicity, including neurological and cardio‐respiratory abnormalities. Highly protein‐bound, CBZ is not removed efficiently through conventional hemodialysis. Charcoal hemoperfusion is the most effective extracorporeal elimination therapy for CBZ intoxication. Recent reports have indicated that continuous venovenous hemodiafiltration (CVVHDF), albumin‐enhanced continuous venovenous hemodialysis, high‐flux hemodialysis and plasma exchange can be as effective as charcoal hemoperfusion. In contrast to recent reports, which demonstrated the effectiveness of CVVHDF with high dialysate flow in CBZ intoxication, we observed that serum CBZ level was decreased minimally by albumin‐enhanced CVVHDF with low dialysate flow. Therefore, albumin‐enhanced CVVHDF with high dialysate flow should be considered in severe CBZ intoxication, if hemoperfusion is unavailable because of the lack of facilities or if it cannot be performed. 相似文献
999.
Seonyeob Kim Ji Young Jung Han Ho Song Seung Jin Song Kook Young Ahn Sang Min Lee Young Duk Lee Sanggyu Kang 《International Journal of Hydrogen Energy》2014
In a previous study, a new hybrid system of molten carbonate fuel cell (MCFC) and homogeneous charge compression ignition (HCCI) engine was developed, where the HCCI engine replaces the catalytic burner and produces additional power by using the left-over heating values from the fuel cell stack. In the present study, to reduce the additional cost and footprint of the engine system in a hybrid configuration, the possibility of engine downsizing is investigated by using two strategies, i.e. the use of a turbocharger and the use of high geometric compression ratio for the engine design, both of which are to increase the density of the intake charge and thus the volumetric efficiency of the engine. Combining these two strategies, we suggest a new engine design with ∼60% of displacement volume of the original engine. In addition, operating strategies are developed to run the new hybrid system under part load conditions. It is successfully demonstrated that the system can operate down to 65% of the power level of the design point, while the system efficiency remains almost unchanged near 63%. 相似文献
1000.
Chung Sub Kim Oh Wook Kwon Sun Yeou Kim Sang Un Choi Ki Hyun Kim Kang Ro Lee 《Lipids》2014,49(11):1151-1159
In the course of our continuing search for bioactive constituents of Korean medicinal plants, we isolated five new oxylipins, chaenomic acid A–E ( 1 – 5 ), and six known ones ( 6 – 11 ) from the twigs of Chaenomeles sinensis. The structures of the new compounds ( 1 – 5 ) were determined by spectroscopic methods, including 1D and 2D NMR (1H and 13C NMR, 1H–1H COSY, HMQC, HMBC, and NOESY), olefin cross‐metathesis, and LC/MS analysis. The known compounds ( 6 – 11 ) were identified by comparison of their spectroscopic data and specific optical rotation with the reported data. The isolated compounds ( 1 – 11 ) were tested for their inhibitory effects on nitric oxide production in lipopolysaccharide‐activated murine microglial cells and for their cytotoxic activities against four human cancer cell lines (A549, SK‐OV‐3, A498, and HCT‐15). 相似文献