• Title/Summary/Keyword: sample introduction efficiency

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Analytical Performance Evaluation of Pneumatic Nebulizers and Comparison of Their Characteristics (가압분무기의 성능 평가와 특성 비교)

  • Park, Chang Joon;Han, Myung Sub;Song, Sun Jin;Lee, Dong Soo
    • Analytical Science and Technology
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    • v.15 no.2
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    • pp.120-126
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    • 2002
  • The analytical performance of four commercially-available pneumatic nebulizers(Meinhard, Cross-flow, Babington, ESI PFA) was evaluated using inductively coupled plasma-atomic emission spectrometry (ICP-AES) and ICP-mass spectrometry (ICP-MS) instruments. The performance of an inert concentric nebulizer and a modified conespray nebulizer, made in Korea Research Institute of Standards and Science (KRISS), is compared with that of the four commercial nebulizers. Variation of sample introduction efficiency was investigated as carrier argon pressure and sample uptake rate were changed. Variation of sensitivity, signal stability, blank intensity and oxide/hydride ratios were also studied when the nebulizers were connected to the ICP-MS and ICP-AES instruments. It was found that good analytical result such as high sensitivity, low blank, stable signal and so on can be obtained with judicious selection of the nebulizer depending on the type of sample, sample amount, type of analytical instrument and analyte.

Optimization of Solid Phase Extraction Method for Quantitative Analysis of Perfluorooctanoic Acid in Serum using Liquid Chromatography-Tandem Mass Spectrometry

  • Lee, Hyun-Seok;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • v.5 no.1
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    • pp.30-33
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    • 2014
  • A solid phase extraction (SPE) method was optimized for the quantitative analysis of perfluorooctanoic acid (PFOA) in serum using hydrophilic-lipophilic balance SPE and LC-MS/MS. Fetal bovine serums spiked with $^{13}C_8$-PFOA before or after SPE were used as test samples for evaluation of the SPE efficiency. Simultaneous evaluation of matrix effects and absolute SPE recovery for $^{13}C_8$-PFOA in serum using different sample pre-treatments and SPE conditions allowed optimization of SPE process efficiency with minimal matrix effect and decent SPE recovery. Introduction of protein precipitation as a sample pre-treatment procedure for serum samples before SPE generally decreased matrix effect in LC-MS/MS analysis and provided more stable recovery of PFOA.

Optimization of Automated Suspension Trapping Digestion in Bottom-Up Proteomics via Mass Spectrometry

  • Haneul Song;Yejin Jeon;Iyun Choi;Minjoong Joo;Jong-Moon Park;Hookeun Lee
    • Mass Spectrometry Letters
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    • v.15 no.1
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    • pp.62-68
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    • 2024
  • The Suspension Trapping (S-Trap) method has been a prominent sample preparation technique since its introduction in 2014. Its capacity to induce protein aggregation using organic solvents has significantly improved protein purification and facilitated peptide identification. However, its full potential for automation has been limited by the lack of a suitable liquid handling system until recently. In this study, we aimed to enhance the automation of S-Trap sample preparation by optimizing the S-Trap digestion process, incorporating triethylammonium bicarbonate (TEAB) and CaCl2. The utilization of TEAB buffer conditions in this innovative process led to a noteworthy 12% improvement in protein identification. Additionally, through careful observation of various incubation conditions, we streamlined the entire sample preparation workflow into a concise 4 hours timeline, covering reduction, alkylation, and trypsin incubation stages. This refined and expedited automated S-Trap digestion process not only showcased exceptional time efficiency but also improved trypsin digestion, resulting in increased protein identification.

The Impact of Capital Adequacy and Operating Efficiency on Saudi Banks Performance

  • Khaled Subhi, RAJHA
    • The Journal of Asian Finance, Economics and Business
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    • v.10 no.2
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    • pp.333-341
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    • 2023
  • This study investigates the impact of capital adequacy and operating efficiency on the performance of Saudi banks. In the first part, the study includes a brief introduction focused on the impact of capital adequacy and operating efficiency on the performance of banks. In the second part, a literature review examined various studies on the impact of capital adequacy and operating efficiency on banks' performance. The study methodology was presented in the third part, based on a sample that included all local Saudi banks from 2010 to 2021, using a study model to answer the study hypotheses. The results of the panel data regression indicated that CAR had a negative and significant effect on ROA and ROE but a negative and non-significant effect on NIM. CIR has a negative and significant effect on ROA, ROE, and NIM, while SIZE, LTD, and MS have a positive and significant effect on ROA, ROE, and NIM. Elimination of defects has no significant effect on return on assets, return on equity, and the NIF. But CR has no significant effect on ROA and ROE but has a positive and significant effect on NIM.

An Analysis on the Efficiency and the Determinants of International Competitiveness of Korean Power Plant Service Industry (국내 발전정비산업의 효율성 및 경쟁력 결정요인 분석)

  • Kim, Hyun Jae;Park, Changsuh
    • Environmental and Resource Economics Review
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    • v.19 no.2
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    • pp.361-382
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    • 2010
  • In 2005, the Korean government decided to postpone the introduction of competition up to 2009 in the power plant service industry. Thus, the purpose of this study is to analyze the efficiency changes and the determinants of international competitiveness of Korean power plant service industry by the comparison between before and after 2006. The sample used in the estimation of efficiency is six firms III Korean power plant service sector for the period of 2003~2008. According to the results, technical efficiency before 2006 (2003~2005) is 0.865 and that after 2005 (2006~2008) is 0.947, which implies that efficiency has been improved after the delay of introduction of competition. In addition, according to the analyses based on the diamond model of Porter using survey data, demand condition has been ranked first in the determinants of international competitiveness. The second and the third important conditions are government and input factor ones. Firm's strategy/structure/competitiveness condition is the most weak condition. Therefore, it would be necessary for firms to improve this condition for competitiveness.

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중학교 3학년 수학교육에서 수학사의 활용

  • 김기원;감혜성
    • Journal for History of Mathematics
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    • v.16 no.2
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    • pp.71-86
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    • 2003
  • Mathematics becomes more indispensible course today, while it seems approaching to the middle school students as a boring and hard one. So, we need to take more motivational teaching devices as well as mere emphases on its importance in order to keep the students up to tile curriculum and improve the education efficiency. Then, history of mathematics call lie one major source of the motivation, since, by telling the tales on the specific unit subject, teachers can awake the students'interest naturally. Today, most of the mathematics textbooks for the middle school students have some historical tales about each unit subject in their respective unit introduction. However, many tales don't seem quite helpful or motivating to understand unit subjects, for they are either abstract or fragmental. In that sense, this paper has three sample guidelines for teaching, which ate meant to introduce historical tales to motivate the students before teachers may get into tile main unit subject. Those suggested in this paper may work as the motivational teaching devices which would make the students mote interested, more positive, and consequently more successful in mathematics.

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A Study on the Adequacy of an Archival Arrangement for Government Publications Collections (정부간행물 정리에 있어서의 보존문서 분류법 적용에 관한 연구)

  • Koo Jayoung
    • Journal of the Korean Society for Library and Information Science
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    • v.8
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    • pp.209-232
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    • 1981
  • The study aims at bringing to the attentions of Korean librarians the ways and means with government publications, which had hardly been brought to the scene yet. It deals with the characteristics of archives and the nature of an archival arrangement based on 'the principle of provenance' ; the characteristics of government publications in relation to the adequacy of an archival arrangement; the three major devices in use for organizing government publications; and introduction to two sample classification systems. The study concludes with a notion that a vast reservoir of information sources(government publications) should be tapped and put to the use of researchers without delays inherent in library processing. It advocates an archival arrangement for economy and efficiency.

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Impact of Marketing Losses on Efficiency in Transacting Banana in Scarce Rainfall Zone of Andhra Pradesh, India

  • Kumar, K. Nirmal Ravi
    • Agribusiness and Information Management
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    • v.9 no.2
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    • pp.1-11
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    • 2017
  • Introduction: To analyze the impact of marketing losses on efficiency in transacting banana in Kurnool district of SRZ in Andhra Pradesh and to assess the opinions of the farmers on the constraints in transacting banana. Research back ground, Materials and Methods: The study relies exclusively on primary information obtained from the banana farmers of Kurnool District. Purposive sampling procedure was followed for the selection of the study area. Top two mandals in the district and top two villages in each mandal are selected in accordance with the area under cultivation of banana. Probability proportion to size was followed regarding the selection of sample farmers and accordingly 60 marginal, 37 small and 23 other farmers were selected and thereby, the total sample size was 120. Result and Discussion: Three marketing channels were identified in the marketing of banana in Kurnool district viz., Producer ${\rightarrow}$ Local-exporter ${\rightarrow}$ Wholesaler ${\rightarrow}$ Retailer ${\rightarrow}$ Consumer (Channel-I), Producer ${\rightarrow}$ Wholesaler ${\rightarrow}$ Cart-vendor ${\rightarrow}$ Consumer (Channel-II) and Producer ${\rightarrow}$ Juice-holder ${\rightarrow}$ Consumer (Channel-III). With the inclusion of marketing losses in the price spread analysis of banana in all the three channels, the marketing costs of all the intermediaries were increased and thereby, the farmer's share in consumer's rupee and Net Marketing Margins of the agencies are on the decline. So, without inclusion of marketing losses, the farmer's share in consumer's rupee and Net Marketing Margins of all the agencies are overvalued. The higher the marketing losses, the more is the negative impact on farmer's net selling price, net marketing margins of the intermediaries and marketing efficiency. The sample farmers are facing major problems in marketing of banana like frequent price fluctuations, unorganized marketing and lack of transportation facilities on priority basis. Suggestions: It is suggested to educate the farmers regarding the optimum maturity index for harvest, use of mechanical harvesters, proper placement of fruits during storage and ripening, better packaging and cushioning technologies to absorb shocks during transportation, strengthening of storage facilities and transport facilities, encourage co-operative marketing etc., to promote marketing efficiency of banana in the study area.

The Impact of HQ-subsidiary Cooperation on Time Efficiency in International Rollout (국제신제품시판 시간효율성에 대한 본사-자회사간 협력의 영향에 관한 연구)

  • Lee, Keon-Bong
    • International Commerce and Information Review
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    • v.15 no.1
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    • pp.117-134
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    • 2013
  • This study examines the moderating effect of HQ-subsidiary cooperation on the relationships between standardization and on-time completion of new product development (NPD) and international new product rollout (INPR). It was empirically tested by a Korean sample to verify the validity of the research framework. The results show that the higher the HQ-subsidiary/agent cooperation, the stronger the effect of NPD timeliness on INPR timeliness. However, HQ-subsidiary cooperation does not moderate the relationship between standardization and INPR timeliness. Under conditions in which the subsidiary and headquarters have a positive relationship, open communications, and regular interactions, more successful new product development in terms of planned time schedule is strongly associated with a much faster introduction to overseas markets.

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The Fundamental Studies and Development of Modified Electrothermal Vaporization Hollow Cathode Glow Discharge Cell (개선된 전열증기화 속빈음극관 글로우 방전셀의 기초연구 및 개발)

  • Lee, Seong-Hun;Cho, Won-Bo;Jeong, Jong-Pil;Choi, Woo-Chang;Kim, Kyu-Whan;Woo, Jeong-Su;Lee, Chang-Su;Kang, Dong-Hyun;Lee, Sang-Chun
    • Analytical Science and Technology
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    • v.15 no.6
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    • pp.514-520
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    • 2002
  • The electrothermal vaporization (ETV) hollow cathode glow discharge atomic emission spectrometer for analysis of liquid sample has been developed and characterized. This system has improved the sample introduction method of electrothermal vaporization and the hollow cathode glow discharge. The sample introduction method was possible to provide high analyte transport efficiency to the plasma by helix coil made of tungsten material. In addition, small volume samples (<$30{\mu}{\ell}$) could be used. The system has glow discharge cell with special design for improvement of precision. The effect of discharge parameters such as discharge power, gas flow rate has been studied to find optimum condition. The emitted light was effectively carried into detector by fiber optic cable in UV region. The calibration curve of Pb, Cd were obtained with 3 samples.