• Title/Summary/Keyword: Icp

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Numerical modeling of ICP-nitriding system using CFD-ACE+ (CFD-ACE+를 이용한 ICP-nitriding system의 수치 모델링)

  • Ju, Jeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.268-268
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    • 2009
  • 고밀도 유도 결합 플라즈마를 이용한 연료 전기 분리판용 질화 장치를 플라즈마를 모사할 수 있는 3차원 전산 유체 역학 프로그램인 CFD-ACE+를 이용하여 해석하였따. 내장형 안테나 타입의 유도 결합 플라즈마의 전자 온도, 밀도 균일성, 가스 유동, 얇은 기판이 촘촘히 적재 되었을 경우의 플라즈마 특성을 모사하였다.

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Elemental Analysis in Astragali Radix by Using ICP-AES and Determination of the Original Agricultural Place of Oriental Medicine by Using a Chemometrics (ICP-AES를 이용한 황기 속에 함유된 원소의 성분 분석과 Chemometrics를 이용한 한약재의 원산지 규명)

  • Kang, Mi Ra;Lee, Ick Hee;Jun, Hyuong;Kim, Yongseong;Lee, Sang Chun
    • Analytical Science and Technology
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    • v.14 no.4
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    • pp.311-316
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    • 2001
  • We have investigated the trace amount in an oriental medicine in oder to determine the geographical origin by using inductively coupled plasma-atomic emission spectrometry(ICP-AES) and chemometric anlysis with principal component analysis(PCA) and pattern recognition. Astragali Radix from several agricultural places in Korea was selected as an example of the oriental medicine and analyzed by ICP-AES. The dried Astragali Radix sample was treated with $HNO_3$ and $H_2O_2$, then digested using microwave oven. Elements such as Mg, Al, K, Ca, Ti, Mn, Fe, Cu, Zn, and Ba with different concentrations were found an used for the identification of the origin of agriculture places. Especially, the concentration of Al, Fe, Zn and Ti were employed to investigate the relationship between. Astragali Radix and the agricultural places by PCA and pattern recognition. We have made a program that is based on chemometrics in analytical spectroscopy. The results of the chemometrics analysis indicated that a distinction among Yechon and Chechon, Chungson, Kurye and Chinese Astragali Radix could be made. We believe that principal component analysis(PCA) and pattern recognition is a valuable tool to identify the origin of Astragali Radix in terms of the agricultural place.

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Metal Concentrations Analysed in the Inorganic Bulk Pigment Samples by ICP-AES and the Provision Rate of MSDS and Agreement Rate with MSDS (우리 나라에서 제조/사용하는 일부 무기 안료중 ICP-AES를 이용한 주요 중금속 농도와 MSDS 비치율 및 일치율 비교)

  • Kim, Hyoung-Ah;Lee, Kyoung-Joo;Kim, Yong-Woo;Kim, Hyun Wook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.8 no.2
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    • pp.196-208
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    • 1998
  • To improve the quality of environmental measurements and evaluation of the workplace air in the pigment manufacturing industries, we analyzed metal(chromium, cadmium, lead, iron, cobalt, manganese, antimony, titanium, arsenic, and selenium) concentrations by ICP-AES in sixty seven samples of inorganic bulk pigments which are produced and/or used in Korea. We also collected MSDS which has to be supplied by manufacturer and/or supplier and posted in the workplace according to the Hazard Communication Standards, and compared the number of metals listed in each MSDS with the number of metals determined by ICP-AES. Results were as followed; 1. Among seventeen yellowish-colored samples, chromium(2~19%) and lead(0.1~61%) were the two major metals. In thirteen reddish-colored samples, iron was the major component with 37~81%. Cobalt and manganese were detected in blue-colored samples with less than 1%, while antimony and titanium were the major two metals in white-colored pigments with 178~300 ppm and with 36~65%, respectively. 2. In area samples collected in workplace air(one pigments producing factory and five retailer stores), iron and manganese were detected but the concentrations not exceeded the TLVs(1 and $5mg/m^3$, respectively). In three of fifteen samples, the concentrations of lead exceeded the TLV ($0.05mg/m^3$). 3. Two out of seven companies provided MSDS, and the average provision rate was 22.4%. And the coincidence rate of the number of metals referenced in MSDS and determined by ICP-AES mostly accorded, but in one sample, different metal was detected from MSDS. In summary, metals have to be concerned in evaluation of the workplace air dealing with compounds of inorganic pigments dust are cobalt, chromium, iron, manganese, lead and antimony, and these are simultaneously determined by ICP-AES. Taking this opportunity, it is needed to reinforce that the personnel is to be concerned about prevention of workers' ill health regarding to provision of MSDS.

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Rapid and Precise Determination of Pb Isotope Ratios Using Mu1ti-Collector ICP/MS (다검출기 유도결합 플라즈마 질량분석기를 이용한 신속하고 정밀한 Pb 동위원소 분석)

  • 최만식;정창식;신형선;임태선
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.157-171
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    • 2001
  • This study investigated the effects of Pb/Tl ratio, Pb concentration and concomitant matrix elements on the measurement of Pb isotope ratios using multi-collector ICP/MS (AXIOM MC model). Accuracy and reproducibility of Pb isotope ratios in NBS 981 solution were estimated for 42 data measured from March to August 2001. Pb isotopes measured in rocks, bronzes and sediments were compared to data measured by TIMS. Reproducibilities for $^{206}Pb/^{204}Pb,\; ^{207}Pb/^{204}Pb,\;and\;^{208}Pb/^{204}Pb$ ratio were about 500 ppm (2sd) and for $^{207}Pb/^{206}Pb$\;and\;^{208}Pb/^{206}Pb$ were 100~200 ppm for 200 ng of Pb in NBS 981 solution. The optimum conditions for the analysis of Pb isotope ratios with AXIOM MC for best accuracy and reproducibility were defined as follows; 1) Pb/Tl ratio is about 10 2) Pb concentration is about 100 ng/ml 3) correction for mass discrimination is performed by exponential law using 2.3887 of $^{205}Tl/^{203}Tl$ and Pb mass fractionation factor empirically obtained from $ln(^{208}Pb/^{206}Pb)-ln(^{205}Tl/^{203}Tl)$ relationship. The sample data measured with MC/ICP/MS for acid-digested and chemically separated rock samples, and acid-digested bronze samples and sediment samples coincide with those of TIMS within analytical errors. Therefore, MC/ICP/MS is a rapid analytical technique for Pb isotope ratios with the similar precision compared with TIMS.

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Correlation between Optic Nerve Sheath Diameter Measured by Computed Tomography and Elevated Intracranial Pressure in Patients with Traumatic Brain Injury

  • Lim, Tae Kyoo;Yu, Byug Chul;Ma, Dae Sung;Lee, Gil Jae;Lee, Min A;Hyun, Sung Yeol;Jeon, Yang Bin;Choi, Kang Kook
    • Journal of Trauma and Injury
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    • v.30 no.4
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    • pp.140-144
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    • 2017
  • Purpose: The optic nerve sheath diameter (ONSD) measured by ultrasonography is among the indicators of intracranial pressure (ICP) elevation. However, whether ONSD measurement is useful for initial treatment remains controversial. Thus, this study aimed to investigate the relationship between ONSD measured by computed tomography (CT) and ICP in patients with traumatic brain injury (TBI). Methods: A total of 246 patients with severe trauma from January 1, 2015 until December 31, 2015 were included in the study. A total of 179 patients with brain damage with potential for ICP elevation were included in the TBI group. The remaining 67 patients comprised the non-TBI group. A comparison was made between the two groups. Receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of ONSD when used as a screening test for the TBI group including those with TBI with midline shift (with elevated ICP). Results: The mean injury severity score (ISS) and glasgow coma scale (GCS) of all patients were $24.2{\pm}6.1$ and $5.4{\pm}0.8$, respectively. The mean ONSD of the TBI group ($5.5{\pm}1.0mm$) was higher than that of the non-TBI group ($4.7{\pm}0.6mm$). Some significant differences in age ($55.3{\pm}18.1$ vs. $49.0{\pm}14.8$, p<0.001), GCS ($11.7{\pm}4.1$ versus $13.3{\pm}3.0$, p<0.001), and ONSD ($5.5{\pm}1.0$ vs. $4.7{\pm}0.6$, p<0.001) were observed between the TBI and the non-TBI group. An ROC analysis was used to assess the correlation between TBI and ONSD. Results showed an area under the ROC curve (AUC) value of 0.752. The same analysis was used in the TBI with midline shift group, which showed an AUC of 0.912. Conclusions: An ONSD of >5.5 mm, measured on CT, is a good indicator of ICP elevation. However, since an ONSD is not sensitive enough to detect an increased ICP, it should only be used as one of the parameters in detecting ICP along with other screening tests.

Effect of N-sources and NaCl Concentrations in Media on the Intra-and Extracellular Proteinase Activities of Streptococcus cremoris $ML_4$ and Streptococcus lactis $ML_8$ (Streptococcus cremoris $ML_4$ 및 Streptococcus lactis $ML_8$의 생육중 질소원과 염농도가 세포내 및 세포외 프로테이나제 역가에 미치는 영향)

  • Chang, Hae-Choon;Lee, Hyong-Joo
    • Korean Journal of Food Science and Technology
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    • v.21 no.1
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    • pp.86-91
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    • 1989
  • To investigate the effect of NaCl concentration and nitrogen sources in the medium for the Streptococci on the intra- and extracellular proteinase(ICP and ECP) which have been known as one of the major causes for the bitter peptide formation, Streptococcus lactis $ML_8$ and Streptococcus cremoris $ML_4$ strains were incubated at 0-4% NaCl in the medium and Na-caseinate as a nitrogen source 0-100%, and the cell growth, ICP and ECP activities were analyzed. As the concentration of the NaCl in the medium increased, the growth and ECP activity decreased but the ICP $activity/10^{10}$ cells increased on the contrary. This implied that the NaCl in the medium affects only the ECP which is associated mainly to the cell wall and cell membrane but not the ICP activity. When the content of the caseinate instead of other low molecular nitrogen sources were increased in the medium, the cell growth was lowered while the ECP activities increased probably by induction of proteinase production.

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