• 제목/요약/키워드: NA samples

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대전지역 산성강우의 화학적 특성에 관한 연구 (A Study on the Chemical Characteristics of Acid Rain in Taejon City)

  • 구자공;박경렬
    • 한국대기환경학회지
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    • 제9권2호
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    • pp.147-153
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    • 1993
  • From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

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Glycoproteins Contained within Soamsan, a Traditional Oriental Medicine, are the Main Class of Active Ingredients Responsible for the Medicine-induced Immune Stimulation

  • Lee, Jeong-Chae;Lee, Kyung-Yeol;Jung, Ha-Na;Kim, Jae-Gon;Jang, Yong-Suk
    • BMB Reports
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    • 제38권2호
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    • pp.253-257
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    • 2005
  • In our previous study, Soamsan, a traditional Oriental medicine, was shown to enhance the induction of antigen-specific immune responses, and it was speculated that the enhancing activity might be closely associated with glycoproteins contained within the medicine. To elucidate this speculation, protein samples from each component, used in the preparation of Soamsan, were obtained and their immune stimulating activities were tested with mouse splenocytes. All the samples markedly enhanced the lymphocyte proliferation and cytokine secretion by the mouse splenocytes. In particular, the enhancement was significantly higher with the protein sample treatments than with those of the original crude sample. Furthermore, the pronase E- and $NaIO_4$-mediated inhibition of splenocyte-stimulation activity of the protein samples clearly supported that glycoproteins are the main class of active ingredients responsible for the lymphocyte stimulating activity of the samples. Consequently, our findings suggest that glycoproteins might have a pivotal role in Soamsan-mediated immune modulation, although the in vivo effect of the glycoproteins should be further elucidated.

PVC 여과지에서의 환원 방지를 위해 개발된 공기중 6가 크롬 측정방법의 현장 평가 (Field Validation of a Sampling and Analytical Method Developed for Preventing Airborne Hexavalent Chromium Collected on PVC Filter from Reduction)

  • 신용철;백남원
    • 한국환경보건학회지
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    • 제28권2호
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    • pp.109-116
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    • 2002
  • The purpose of this study was to evaluate a new sampling and analytical method for the determination of airborne hexavalent chromium, Cr(Ⅵ), in a field plating operation. The procedures of this new method (Shin & Paik's Method) are as the following: Airborne hexavalent chromium is collected on polyvinyl chloride (PVC) filter according to the National Institute iota Occupational Safety and Health (NIOSH) Method 7600, and the filler sample is placed in a screw-capped vial and soaked with 2% NaOH/3% Na₂CO₃ solution immediately after sampling. The Cr(Ⅵ) sample is analyzed by ion chromatography/visible spectrophotometry (IC/VS) according to the U.S. Environmental Protection Agency (EPA) Method 218.6. The airborne Cr(Ⅵ) concentrations measured by this method were compared with those determined by three reference methods: One (NIOSH/EPA Method) consisted of sampling airborne Cr(Ⅵ) on PVC filters and storing the sample filters in strew-capped vials according to the NIOSH method, and analyzing Cr(Ⅵ) in samples using IC/VS according to the EPA method. The second method (Impinger Method/NaHCO₃) consisted of absorbing airborne Cr(Ⅵ) into 0.02 M NaHCO₃ solution in midget impinger, and analyzing the Cr(Ⅵ) in samples using IC/VS. The third method was the OSHA Method ID-215. Using these four different methods, lour replicates of air samples were collected at an electroplating process and analyzed simultaneously. Two-way ANOVA and paired t-test were used to test difference among values determined by the methods. There was no significant difference and a strong correlation (r²:0.99) between Cr(Ⅵ) concentrations measured by the Shin & Paik's Method and an impinger method (p>0.05). However, Cr(Ⅵ) concentrations determined by Shin & Paik's Method were significant1y different from those by the NIOSH/EPA Method (p<0.05) or the OSHA method (p<0.05). The Cr(Ⅵ) concentrations of Shin & Paik's Method were significantly higher than those of the NIOSH/EPA Method or the OSHA method. This result indicated that the Shin & Paik's Method may prevent Cr(Ⅵ) losses caused by reduction and give more reliable results of airborne Cr(Ⅵ) concentrations in work environments.

원전발생 방사성폐기물 시료 중 초우란원소의 정량 (Determination of Transuranic Elements in Radwaste Samples from Nuclear Power Plant)

  • 조기수;김태현;전영신;지광용;김원호
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2003년도 가을 학술논문집
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    • pp.351-357
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    • 2003
  • 원전발생 방사성폐기물 시료 중 TRU를 정량하기위해 모의 사용 후 핵연료 시료 용액 중 Pu, Am 및 Cm 을 이온교환수지 및 HDEHP 추출크로마토그래피로 분리한 다음 알파분광분석법으로 각 핵종의 함량을 정량하였다. Dowex AG1 음이온수지 에서 12M HC1-0.lMHI 용리액으로 Pu를 분리하고 이차분리관인 HDEHP 흡착 분리 관에서 DTPA-Lactic Acid 용리액으로 Am과 Cm을 군분리하였다. 분리된 Pu, Am 및 Cm은 0.1M $NaHSO_4$-0.53M $Na_2SO_4$ 매질에서 전착한 다음 알파분광분석법으로 $^{239}Pu$, $^{241}Am$$^{244}Cm$의 알파에너지의 방사능을 측정하여 회수율을 추하였다. 비방사성 금속원소 및 우라늄을 포함하는 합성용액 시료중 $^{239}Pu$, $^{241}Am$$^{244}Cm$ 을 측정한 결과 각각 83.8%, 85.2% 및 86.3% 의 회수율을 나타내었다.

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Incidence of exercise-associated hyponatremia during a high-altitude 161-km ultramarathon

  • Khodaee, Morteza;Saeedi, Anahita;Harris-Spinks, Christine;Hew-Butler, Tamara
    • 운동영양학회지
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    • 제25권3호
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    • pp.16-22
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    • 2021
  • [Purpose] Exercise-associated hyponatremia (EAH) is a well-known condition among endurance athletes at low altitudes. The incidence of EAH during ultramarathons at high altitudes warrants further investigation. This prospective observational study was conducted on the participants of the Leadville Trail 100 run, a 161-km race held at a high altitude (2,800 m-3,840 m). [Methods] Venous blood samples were collected before and immediately after the race. The participants completed an electronic survey after the race. Our main outcome measure was the post-race serum sodium ([Na+]) level. [Results] Of the 672 athletes who started the race, 351 (52%) successfully completed the event within the 30-hour cut-off. Post-race blood samples were collected from 84 runners (66 finishers). Both pre- and post-race blood samples were collected from 37 participants. Twenty percent of the post-race participants had EAH. Only one post-race participant had a [Na+] level of <130 mmol/L. All participants with EAH were asymptomatic. One participant had an abnormal pre-race [Na+] level (134 mmol/L). Female participants had a significantly higher rate of EAH than male participants (40% vs. 16%; p=0.039). Age, body mass index, weight changes, race completion status, nonsteroidal anti-inflammatory drug use, and urine specific gravity were not associated with the development of EAH. Lower postrace [Na+] levels were associated with higher serum creatine kinase values (R2=0.1, p<0.005). [Conclusion] High altitude (3,840 m peak) does not appear to enhance the incidence of EAH after an ultramarathon footrace. This suggests that ambient temperature (low temperatures reduce risk), sex (female predilection), endurance running, and overhydration are more prominent risk factors for EAH than high altitude.

미숙 복숭아의 성분 연구 (Studies on the Components of Unripe Peaches)

  • 이주백;정헌식
    • 한국식품저장유통학회지
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    • 제15권1호
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    • pp.79-83
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    • 2008
  • 4월 20일과 5월 2일 적과된 미숙 복숭아의 식품학적 특성을 조사하였으며, 평균중량은 각각 $4{\sim}6g$, $10{\sim}15g$이었다. 유기산 함량은 oxalic acid 함량이 가장 높았으며, cirtric acid, malic acid, tartaric acid 순으로 나타났고 유기산의 구성비가 변화하였다. 적과시기에 관계없이 모든 시료에서 arabinose가 검출되었으며, 부위별로 유리당 조성은 차이를 나타내었는데 4월 20일과 5월 2일 과육부 당의 주체는 arabinose와 sucrose이었으며 과피부의 당의 주체는 각각arabinose와 glucose 및 sucrose 이었다. 주요 아미노산으로는 aspartic acid로서 함량이 가장 높아 전체 아미노산의 $22{\sim}34%$를 차지하는 것으로 나타났다. 다음으로 proline, glutamic acid, serine, leucine, Iysine의 순으로 나타났다 무기물 중 K의 월등히 높은 함량을 보였고 다음으로 Ca, Mg, Na 순이었다.

Nonresponse in Repeated Surveys

  • Park, Hyeon-Ah;Na, Seong-Ryong;Jeon, Jong-Woo
    • Communications for Statistical Applications and Methods
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    • 제14권3호
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    • pp.593-600
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    • 2007
  • Under repeated surveys, missing values often appear for various reasons and are replaced by new samples. It is investigated that the existing estimator in repeated survey by Jessen (1942), which has been originally developed for the new samples of fixed size, can be used in such situation where the size of new samples is random. It is shown that the proposed estimator has smaller variance than the sample mean.

Presalting Condition Effects on the Development of Pink Color in Cooked Ground Chicken Breasts

  • Bae, Su Min;Cho, Min Guk;Jeong, Jong Youn
    • 한국축산식품학회지
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    • 제40권2호
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    • pp.197-208
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    • 2020
  • The effects of presalting conditions (storage temperature and duration) with/without sodium tripolyphosphate (STPP) on the color and pigment characteristics of cooked ground chicken breast were investigated. Meat mixtures containing 2% NaCl (control) or 2% NaCl and 0.5% STPP (STPP treatment) were stored for 0, 3, 5, 7, and 10 d at 2℃ or 7℃, followed by cooking to 75℃, and cooling and storage at 2℃-3℃ until further analysis. The treatment was the most effective on the pink color defect of all independent variables. The effect of storage temperature was only observed on CIE L values and percentage myoglobin denaturation (PMD). The control was redder than the STPP treated samples and the CIE a values increased (p<0.05) from 0 to 5 d in the control and STPP treated samples. Compared to the STPP treatment, the control exhibited increased reducing conditions (more negative oxidation reduction potential), lower undenatured myoglobin, and greater PMD. No differences in the cooking yields of the control and STPP-treated samples were observed for various storage durations. Products with STPP showed higher (p<0.05) pH values than those without STPP, but no differences (p>0.05) in PMD were observed over the storage period in the control and STPP treated samples, except for day 0. Thus, STPP is effective at reducing the pink color in cooked chicken breasts. In addition, presalting for longer than 5 d resulted in increased pink color of the cooked chicken breasts.

Identification of Lactic Acid Bacteria in Galchi- and Myeolchi-Jeotgal by 16S rRNA Gene Sequencing, MALDI-TOF Mass Spectrometry, and PCR-DGGE

  • Lee, Yoonju;Cho, Youngjae;Kim, Eiseul;Kim, Hyun-Joong;Kim, Hae-Yeong
    • Journal of Microbiology and Biotechnology
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    • 제28권7호
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    • pp.1112-1121
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    • 2018
  • Jeotgal is a Korean traditional fermented seafood with a high concentration of salt. In this study, we isolated lactic acid bacteria (LAB) from galchi (Trichiurus lepturus, hairtail) and myeolchi (Engraulis japonicas, anchovy) jeotgal on MRS agar and MRS agar containing 5% NaCl (MRS agar+5% NaCl), and identified them by using 16S rRNA gene sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as culture-dependent methods. We also performed polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) as a culture-independent method to identify bacterial communities. Five samples of galchi-jeotgal and seven samples of myeolchi-jeotgal were collected from different regions in Korea. A total of 327 and 395 colonies were isolated from the galchi- and myeolchi-jeotgal samples, respectively. 16S rRNA gene sequencing and MALDI-TOF MS revealed that the genus Pediococcus was predominant on MRS agar, and Tetragenococcus halophilus on MRS agar+5% NaCl. PCR-DGGE revealed that T. halophilus, Tetragenococcus muriaticus, and Lactobacillus sakei were predominant in both types of jeotgal. T. halophilus was detected in all samples. Even though the same species were identified by both culture-dependent and -independent methods, many species identified by the culture-dependent methods were not in the bacterial list identified by the culture-independent methods. The distribution of bacteria in galchi-jeotgal was more diverse than in myeolchi-jeotgal. The diverse LAB in galchi- and myeolchi-jeotgals can be further studied as candidates for starter cultures to produce fermented foods.

Fundamental Study on Solvent Sublation Using Salphen and Its Application for Separative Determination of Trace Ni(II), Co(II) and Cu(II) in Water Samples

  • Kim, Young-Sang;In, Gyo;Kim, Mi-Hyun;Choi, Jong-Moon
    • Bulletin of the Korean Chemical Society
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    • 제27권11호
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    • pp.1757-1762
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    • 2006
  • A solvent sublation using salphen as a ligand was studied and applied for the determination of trace Ni(II), Co(II) and Cu(II) in water samples. The fundamental study was investigated by a solvent extraction process because the solvent sublation was done by extracting the floated analytes into an organic solvent from the aqueous solution. The salphen complexes of Ni(II), Co(II) and Cu(II) ions were formed in an alkaline solution of more than pH 8 and then they were extracted into m-xylene. It was known that the each metallic ion formed 1 : 1 complex with the salphen and the logarithmic values of extraction constants for the complexes were 3.3 5.1 as an average value. Based on the preliminary study, the procedure was fixed for the separation and concentration of the analytes in samples. Various conditions such as the pH of solutions, the influence of $NaClO_4$, the bubbling rate and time of $N_2$ gas, and the type of organic solvent were optimized. The metal-salphen complexes could be extracted into m-xylene from the solution of more than pH 8, but the pH could be shifted to acidic solution of pH 6 by the addition of $NaClO_4$. In addition, the solvent sublation efficiency of the analytes was increased by adding $NaClO_4$. The recovery of 97-115% was obtained in the spiked samples in which given amounts of 0.3 mg/L Ni(II), 0.8 mg/L Co(II) and 0.04 mg/L Cu(II) were added.