• Title/Summary/Keyword: Sample pre-treatment

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Analysis of Organic Compounds in Ambient PM2.5 over Seoul using Thermal Desorption-comprehensive Two Dimensional Gas Chromatography-time of Flight Mass Spectrometry (TD-GCxGC-TOFMS) (Thermal Desorption-comprehensive Two Dimensional Gas Chromatography-time of Flight Mass Spectrometry (TD-GCxGC-TOFMS)을 이용한 서울 대기 중 PM2.5 유기성분 분석)

  • Lee, Ji-Yi;Lane, Douglas A.;Huh, Jong-Bae;Yi, Sung-Muk;Kim, Yong-Pyo
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.5
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    • pp.420-431
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    • 2009
  • Characteristics and advantages of the thermal desorption-comprehensive two dimensional gas chromatography-time of flight mass spectrometry (TD-GCxGC-TOFMS) were discussed and the organic compound's analysis result was shown for the ambient $PM_{2.5}$ sample collected in Seoul, Korea. Over 10,000 individual organic compounds were separated from about $70{\mu}g$ of aerosols in a single procedure with no sample pre-treatment. Among them, around 300 compounds were identified and classified based on the mass fragmentation patterns and GCxGC retention times. Several aliphatic compounds groups such as alkanes, alkenes, cycloalkanes, alkanoic acids, and alkan-2-ones were identified as well as 72 PAH compounds including alkyl substituted compounds and 8 hopanes. In Seoul aerosol, numerous oxidized aromatic compounds including major components of secondary organic aerosols were observed. The inventory of organic compounds in $PM_{2.5}$ of Seoul, Korea suggested that organic aerosol were constituted by the compounds of primary source emission as well as the formation of secondary organic aerosols.

Development of Multi-residue Analytical Method for 261 Pesticides in Herbal Medicines using GC-MS/MS and LC-MS/MS (GC-MS/MS와 LC-MS/MS를 이용한 생약재 중 261종 농약의 동시분석)

  • Na, Eun Shik;Kim, Seong Soo;Hong, Sung Soo;Kim, Kyoung Ju;Lee, Yong Jae;Lee, Byung Chul;Lee, Kyu Seung
    • Korean Journal of Environmental Agriculture
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    • v.39 no.2
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    • pp.142-169
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    • 2020
  • BACKGROUND: A new analytical method has been developed to determine 261 pesticide residues in herbal medicines. METHODS AND RESULTS: The extraction of pesticides was carried out by modified method of the Korea Food Standards Codex sample extraction and determination was performed using GC-MS/MS and LC-MS/MS. During the pre-treatment process of the test method, Solid-liquid separation was changed to centrifugation. The method was validated by the precision and accuracy results. 261 pesticides spiked at three level 20, 50, 100 ug/kg in herbal medicines. The limit of quantification of method were 4-40 ug/kg for GC-MS/MS and 2-45 ug/kg for LC-MS/MS, respectively. Among the pesticides analysed by GC-MS/MS and LC-MS/MS, 244 pesticides (94% of total number) in chinese matrimony vine and 224 pesticides (86% of total number) in korean angelica root and 231 pesticides (89% of total number) in jujube and 214 (82% of total number) in cnidium showed recoveries in the range of 70-120% with RSD⪯20%. CONCLUSION: These results indicated that GC-MS/MS and LC-MS/MS analysis with the sample extraction in this study can be applied to multi-residue analysis of pesticides in herbal medicines.

Photosynthesis and Respiration (P&R) Analyzer Analysis Optimization for Microalgal Activity Evaluation (미세조류 활성도 평가를 위한 Photosynthesis and Respiration (P&R) Analyzer 분석조건 최적화)

  • Huh, Jae-Hee;Sim, Tae-Suk;Hwang, Sun-Jin
    • Journal of Korean Society on Water Environment
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    • v.37 no.6
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    • pp.449-457
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    • 2021
  • Photosynthesis and respiration rate of microalgae are important factors during advanced wastewater treatment research using microalgae, There are several equipments and measurement methods for measuring photosynthesis and respiration, with different challenges that occur during pretreatment and stabilization of the analysis process. Therefore, in this study, for accurate Photosynthesis and Respiration (P&R) analyzer measurement, the analysis process was divided into pre-processing, DO stabilization, and analysis stages and each was optimized to enable accurate evaluation. For this purpose, the effect of DO saturation of the sample on P&R analysis, DO stabilization according to the degassing flow rate, and photoinhibition of the OD level on photosynthesis was investigated. Based on our study results, when DO was supersaturated, photosynthetic efficiency decreased due to photorespiration, making it inappropriate as a P&R sample. In addition, 0.5 L-N2/min level was the optimal nitrogen degassing flow rate for DO desaturation. The inhibition of photosynthetic efficiency by self-shading caused by the increase in OD was observed from OD 2.0, and it was found that P& R analysis is preferably performed on samples with OD less than 2.0. In addition, based on the above three optimization results, an optimized P&R Analyzer instruction for accurate P&R analysis was also presented.

Analgesic Effect of a Traditional Korean Medicine Yang Eui Gongjin-dan on Severe Pain: A Retrospective Study (兩義供辰丹을 倂用한 한방치료가 重症度의 통증 환자에 미치는 진통 효과 : 후향적 연구)

  • Lee, Dong-hyuk;Lee, Young-eun;Lee, Bo-yun;Kim, Yeon-jin;Cho, Seung-yeon;Park, Seong-uk;Jung, Woo-sang;Moon, Sang-kwan;Ko, Chang-nam;Cho, Ki-ho;Park, Jung-mi
    • The Journal of Internal Korean Medicine
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    • v.36 no.3
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    • pp.265-275
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    • 2015
  • Objectives: The aim of this study was to investigate the analgesic effect of Yang Eui Gongjin-dan (YEGJD), a traditional Korean medicine, on severe pain or numbness, including acute and chronic non-cancer pain. Methods: Records of patients visiting the Department of Traditional Korean Internal Medicine, Stroke and Neurological Disorders Center, from March 2011 to January 2015, were searched. Their chief complaint was severe numbness or pain (NRS≥7). We compared the NRS of pain pre- and post-YEGJD treatment in 34 patients; and analyzed changes in pain severity pre- and post-YEGJD treatment in 17 chronic non-cancer pain patients. We also investigated other accompanying symptoms, such as insomnia, anorexia, dyspepsia, fatigue, coldness, and excessive sweating, related to the deficiency state (虛症) in traditional Korean medicine. Results: The average pain NRS for the 34 patients significantly decreased from 8.04±1.08 to 3.75±2.54 after YEGJD treatment. The average pain NRS score in chronic non-cancer pain patients also significantly declined from 7.91±0.97 to 3.29±2.29. Conclusions: The traditional Korean medicine Yang Eui Gongjin-dan has an analgesic effect and is useful for treating severe pain or numbness. We recommend a randomized controlled trial using objective assessment scales and a large patient sample to further test the effects of Yang Eui Gongjin-dan.

Effects of Multisensory Stimulation Using Familiarity: Persons with Dementia in Long-term Care Facility in Korea (익숙함을 이용한 다감각적 자극 프로그램의 효과: 시설 입소 치매 노인)

  • HongSon, Gwi-Ryung
    • Journal of Korean Academy of Nursing
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    • v.41 no.4
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    • pp.528-538
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    • 2011
  • Purpose: The purpose of the study was to examine the effects of multisensory stimulation (MSS) using familiarity on persons with dementia (PWDs) residing in nursing homes in Korea. Methods: A nonequivalent control group with pre and posttests was used. Fifty one PWDs were included if they: 1) were over 65 yr old, 2) were diagnosed with dementia, 3) had no visual or speech impairments, 4) were able to communicate, and 5) had spent more than one month in a nursing home. The experimental group (n=25) received a 55 min MSS program twice a week for 10 weeks. The outcome variables included were cognition, activities of daily living, grip strength, depression, wandering, and aggressive behaviors. Repeated ANOVA was used for data analysis. Results: There were no significant differences in demographics or the main variables at pretest. Cognition, depression, wandering, and aggressive behaviors were significant over time between the two groups. Grip strength was only significant when accounting for interaction between group and time. Conclusion: An intervention of MSS using familiarity was marginally effective in improving cognition, depression, wandering, and aggression. Future study is suggested with a larger sample and longer treatment to retest the effects of MSS.

Evaluation of Nutrition Education for Insulin Dependent Diabetic Students (인슐린 의존성 당뇨병 학생을 대상으로 실시한 영양교육의 효과)

  • 이정희;박동연;윤진숙
    • Journal of Nutrition and Health
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    • v.28 no.10
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    • pp.1015-1021
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    • 1995
  • This study was conducted to evaluate changes in nutritional knowledge, attitudes, behavior intention and behavior in a sample of 27 insulin dependent diabetic students participating in diabetics' camp. Nutritional knowledge related to diabetes, attitudes toward diabetes treatment and behavior intention about dietary changes were tested before and after nutrition education. Six months after nutrition education, an open ended questionnaire about their actual behavior changes was mailed to all participants and 17 of them responded. Pre-and post-testing showed that nutrition education was effective in significant changes in knowledge and in promoting positive attitudes and behavior intention. Increases of knowledge were consistently the same regardless of sex, level of education, regularity of diet, and duration of disease. Compared to male students, female students showed more positive change in knowledge, attitudes and behavior intention. It also appeared that middle school students showed more positive improvement in knowledge, attitudes and behavior than elementary and high school students. A follow-up test showed that their actual behavior changes were not squared with their behavior intention. They pointed out difficulties in having proper amount of meals and snack and the conflict with school time schedule as the major reason for discordance. These findings suggest that nutrition education for diabetics can be effective to improve their knowledge, attitudes and behavior intention and understanding about barriers to behavior change is important for better compliance to the disease.

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Performance of one batch type and multi functional pre-treatment agent for CPB process (CPB용 다기능성 일욕형 전처리 조제의 성능)

  • Park, Beob;Cho, Yeon-Jeong;Koo, Kang
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2012.03a
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    • pp.61-61
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    • 2012
  • 현재 기능성 의류 섬유시장에서도, 요구하는 주요 기능들의 퍼포먼스 수준을 보여주는 과학적 수치들과 함께 기능성 섬유제작 과정에서 얼마나 친환경적인 제조과정을 거쳤는가에 대한 정보들도 요구하고 있는 중이다. 섬유에 인간과 환경에 유해한 성분이 최대한 배제됐으며 생산 과정에서의 자연자원의 낭비가 이뤄지지 않았음을 증명해야한다. CPB 전처리 공정은 혼방직물과 같이 서로 다른 물성을 가지는 직물에 대한 저온 처리로 섬유 손상을 최소화하고, $CO_2$ 발생량 및 에너지 소비량을 감소시킬 수 있는 이점이 있다. CPB 전처리는 호발, 정련, 표백을 포함하는 공정으로 일욕으로 처리 시 패딩, 수세, 와인딩 공정을 단축시키기 때문에 약품 소비량 감소와 에너지 사용 절감 효과가 있어 전 세계적으로 확산되고 있는 Green Technology이다. 본 연구에서는 CPB용 전처리 조제(4~5종)을 일욕화 하여 가공업체 생산성 향상 및 원가절감, 환경유해성 감소를 목표로 하여 CPB 전처리의 최적 가공조건을 확립하는 것이 목표이다. 첨가 용제의 종류 및 첨가량을 변화시켜 각 조성비에 따른 sample을 제조하여 정련성, 호발성, 알칼리 안정성, Whiteness를 측정하여 전처리 성능을 분석하고, 과수안정성, 금속이온 봉쇄력을 비교하여 최적 조성비 및 중합조건을 확립하였다.

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Fracture Behavior of Oxide Scales and Influence of Oxide Scales on the Strength of Materials (산화피막의 파괴거동 및 산화피막이 소지금속의 기계적 강도에 미치는 영향)

  • ;;Narita Toshio
    • Transactions of Materials Processing
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    • v.13 no.1
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    • pp.72-77
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    • 2004
  • An Fe-25Cr steel was oxidized in Ar atmosphere at 973K with and without applying external stress of 30∼35 MPa. A 0.1$\mu\textrm{m}$ thick $Cr_2O_3$ scales formed during pre-treatment in Ar atmosphere. Initiation of cracking on the oxide scales took place at grain boundaries during the end of second creep stage, in which cracks were found nearly perpendicular to the tensile directions. On the contrary, a scale developed in $N_2$-0.1%$SO_2$ displaced a poor adherence on the metal substrate. In this sample, a fast grown of scales was observed during creep deformation, and the strength of materials was much lower than in Ar. The creep strain rate of $1.5{\times}10^{-7}/s$ and $5.8{\times}10^{-7}/s$ was determined in Ar and in $N_2$-0.1%$SO_2$ under 30MPa, respectively.

Radio-Carbon Age Determination by Tandem Accelerator Mass Spectrometry Technique and Its Application To The Korean Sea (탄뎀가속기에 의한 방사성탄소 년대측정과 한국해에의 적용)

  • Suk, Bong-Chool;Toshio Nakamura;Nobuyuki Nakai;Asahiko Taira
    • The Korean Journal of Quaternary Research
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    • v.4 no.1
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    • pp.27-40
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    • 1990
  • $^{14}C$ age dating by AMS (accelerator mass spectrometry) technique was performed on twenty five small sized fossil shells and one peat taken from the sixteen piston cores in the southern and southeastern Korean Sea. AMS technique is available to date only a few milligram of amorphous carbons compare than conventional dating technique. It is described in detail of sample pre-treatment and experimental, and applied to the reconstruction of the sea level changes since the late Pleistocene in the Korean Sea. Dated age ranges from 520$\pm$100 to older than 33,500 years. Sedimentary facies in the study area represents a different environmental set which is affected by sea level fluctuation since the late Pleistocene.

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The Study for Development of Day Hospital Program of Eating Disorders (섭식장애를 위한 낮병원 프로그램 개발에 관한 연구)

  • 공성숙
    • Journal of Korean Academy of Nursing
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    • v.34 no.1
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    • pp.25-34
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    • 2004
  • Purpose: The purpose of this study was to develop the day hospital program for Korean eating disorders patients and to examine the effect of the day hospital program on improving frequency of binging and purging, eating disorders symptoms, self-esteem, and depression. Method: The subjects were 24 binge eaters visited at eating disorders clinic 'M'. They participated in a modified day hospital program based on the Toronto Day Hospital Program. All subjects completed the Eating Disorders Inventory(EDI)-2, Rosenberg Self-Eesteem Scale, Beck Depression Inventory(BDI) at pre and post intervention, and recorded daily food records. Results: In paired t-test analysis, frequency of binging and purging, self-esteem, depression, and 11 sub-scales of EDI-2(drive for thinness, bulimia, body dissatisfaction, ineffectiveness, interoceptive awareness, perfectionism, interpersonal distrust, maturity fear, asceticism, impulse regulation, social insecurity) were significantly improved after treatment. Conclusion: The results of this study suggest that the day hospital program for Korean eating disorders patients may be an effective initial approach to overcoming various eating disorders symptoms. Further studies should investigate longer term outcome data using a larger sample.