• 제목/요약/키워드: acid gas

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이산화질소 가스에 의한 무화과 나무의 피해 양상 (The Toxicity of Nitrogen Dioxide Gas on Fig Plant)

  • 김유학;최병렬;김명숙
    • 한국토양비료학회지
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    • 제43권6호
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    • pp.978-980
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    • 2010
  • This study was conducted to observe the cause of injury of fig plant. Nitrogen dioxide gas can be evolved at low pH or reduced in soil. Fig plant cultivated with nutrient solution was wilted or withered. Injury symptom for nutrient solution containing nitrous acid was worse as pH of soil decreased. However, increase in pH of nutrient solution treated with increasing $Ca(OH)_2$ solution prevented nutrient solution from producing nitrogen dioxide gas. Recovery of the fig plant by pH increase indicated that the cause of injury was nitrogen dioxide gas.

Efficiency of Gas-Phase Ion Formation in Matrix-Assisted Laser Desorption Ionization with 2,5-Dihydroxybenzoic Acid as Matrix

  • Park, Kyung Man;Ahn, Sung Hee;Bae, Yong Jin;Kim, Myung Soo
    • Bulletin of the Korean Chemical Society
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    • 제34권3호
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    • pp.907-911
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    • 2013
  • Numbers of matrix- and analyte-derived ions and their sum in matrix-assisted laser desorption ionization (MALDI) of a peptide were measured using 2,5-dihydroxybenzoic acid (DHB) as matrix. As for MALDI with ${\alpha}$-cyano-4-hydroxy cinnamic acid as matrix, the sum was independent of the peptide concentration in the solid sample, or was the same as that of pure DHB. This suggested that the matrix ion was the primary ion and that the peptide ion was generated by matrix-to-peptide proton transfer. Experimental ionization efficiencies of $10^{-5}-10^{-4}$ for peptides and $10^{-8}-10^{-7}$ for matrices are far smaller than $10^{-3}-10^{-1}$ for peptides and $10^{-5}-10^{-3}$ for matrices speculated by Hillenkamp and Karas. Number of gas-phase ions generated by MALDI was unaffected by laser wavelength or pulse energy. This suggests that the main role of photo-absorption in MALDI is not in generating ions via a multi-photon process but in ablating materials in a solid sample to the gas phase.

β-Cyclodextrin과 Polylactic Acid간의 포접화합물 제조 및 특성 분석 (Preparation and Characterization of Inclusion Complex between β-Cyclodextrin and Polylactic Acid)

  • Nan, Song Ya;Fang, Zhou Yu;Jun, Zhen Wei
    • 폴리머
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    • 제39권2호
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    • pp.261-267
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    • 2015
  • The inclusion complexes (ICs) between polylactic acid (PLA) and ${\beta}$-cyclodextrin (CD) were prepared by co-precipitation method in this work. The orthogonal experiments were designed to investigate the influence of different factors on the formation of inclusion complexes. The results suggested that the optimum scheme of inclusion compounds could be obtained when the feeding ratio of CD to PLA (wt%) was 20:1, stirring speed was 6 kr/min and the stirring time was 30 min. The structures and properties of the inclusion complexes were characterized by $^1H$ NMR, FTIR, DSC, FT-Raman, XRD and TGA. The DSC results demonstrated that the crystallization behavior of the inclusion complexes nearly disappeared. It was found that ${\beta}$-CD-PLA inclusion complex had a better thermal stability compared with the neat PLA. The model of the inclusion complexes was proposed on the basis of XRD, $^1H$ NMR and DSC results.

마이크로버블을 이용한 냉연 산회수설비공정 발생 염화수소 가스 처리 (Treatment of Hydrochloric acid from Regeneration and Scrubber system of Cold Rolling Mill Plant with Micro-bubble)

  • 정용준;정재억;김예진
    • 한국습지학회지
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    • 제17권2호
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    • pp.118-123
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    • 2015
  • 제강산업의 냉연 산회수 설비공정을 검토하였고, 공정에서 발생되는 염화수소 가스를 처리하기 위하여 마이크로버블이 발생되는 DIWS 시스템을 운전하였다. 염화수소 가스의 대기배출허용기준을 만족하기 위해서는 추가공정의 도입이 필요한 것으로 나타났다. DIWS 장치로 유입되는 평균 염화수소 가스의 농도는 22.3 ppm, 배출가스의 농도는 0.59 ppm으로 평균 제거율은 97.3%였다. TMS 장치에 의한 10시간 5분 간격 측정에서도 평균 0.69 ppm으로 안정적이었으며, 수동으로 측정하여 TMS 장치의 신뢰도를 검증하였다.

Gas Chromatography에 의(依)한 미강유(米糠油)의 지방산분석(脂肪酸分析) (Analysis of Fatty Acid in Rice Bran Oil by Gas Chromatography)

  • 정태명;신종수
    • Applied Biological Chemistry
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    • 제9권
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    • pp.29-33
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    • 1968
  • 1. 미강유중(米糠油中)의 함존지방산(含存脂肪酸)은 Oleic acid, Linoleic acid, Palmitic acid의 순(順)으로 함량(含量)이 많으며 이상(以上) 3종(種) 지방산(脂肪酸)이 주성분(主成分)을 이루고 있다. Stearic acid, myristic acid와 Linolenic acid는 극소량(極少量) 함유(含有)되어 있을 뿐이며 $C_{12}$ 이상(以上)의 산(酸)은 그 흔적(痕迹)이 보이지 않았다. 2. 표준(標準) 지방산(脂肪酸) Methyl로서 구(求)한 보정계수(補正係數)는 포화지방산(飽和脂肪酸)에 있어서 $C_{18}$까지는 탄소수(炭素數)가 증가(增加)함에 따라 커지고 또 동일탄소수(同一炭素數)의 지방산(脂肪酸)에 있어서는 이중결합(二重結合)의 수(數)에 따라 커지고 있다. 3. 지방산(脂肪酸) Methyl Ester의 Retention time의 대수치(對數値)는 포화산(飽和酸)의 탄소수(炭素數), 또는 같은 탄소수(炭素數)의 지방산(脂肪酸)에 있어서 그 이중결합(二重結合)의 수(數)와의 사이에 직선관계(直線關係)가 있다는 것을 확인(確認)했다.

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Protein Hydrolysis with Formic Acid and Analysis of Amino Acid Using Butylthiocarbamyl - trimethylsilyl (BTC - TMS) Derivatives by Gas Chromatography

  • 우강융;이동선;김민철
    • 한국식품영양과학회지
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    • 제32권3호
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    • pp.320-324
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    • 2003
  • 단백질 구성 아미노산 분석을 위한 효과적인 가수분해 방법을 찾기 위하여 0.3% tryptamine을 함유한 6M formic acid와 6M HCI을 표준 아미노산과 단백질 표준품인 bovine serumn albumin 가수분해에 적용하여 표준아미노산의 회수율과 bovine serum albumin의 아미노산 조성을 분석하였고 GC에 의한 효과적인 아미노산 분석을 위하여 새로운 유도체인 butylthiocarbamyl-trimethylsilyl(BTC-TMS)유도체를 개발하여 분석한 결과는 다음과 같았다 표준아미노산의 회수율은 6M formic acid에 의한 가수분해방법이 6M HCI에 의한 가수분해 방법보다 상당히 정확하였고 특히 산 가수분해에서 tryptamine의 존재하에서도 잘 파괴되는 tryptophan의 경우 formic acid가수분해가 HCI가수분해보다 1.5배정도 높은 회수율을 보였다. Bovine serum albumin의 아미노산 조성을 583 아미노산 잔기로 환산하여 나타내었을 경우도 formic acid에 의한 가수분해가 HCI가수분해 경우보다 훨씬 정확하였고 이 때 tryptophan의 회수율도 훨씬 높게 나타났다. 다만 서열분석에서 분석되지 않는 cystine이 formic acid 가수분해시 분석되고 있어 이에 대한 정확한 검정이 필요하였다. BTC-TMS 유도체는 GC분석시 극성이 다소 낮은 DB-l7 column으로 분리가 잘되었고 재현성도 좋았으나 GC분석을 위한 대부분의 유도체에서와 마찬가지로 몇 가지 아미노산에서 두 개의 peak로 나타나는 결점이 있었다.

Lipid and Protein Constituents of Crotalaria juncea L.

  • Javed, Muhammad Akhtar;Saleem, Muhammad;Yamin, Muhammad;Chaudri, Tanvir Ahmad
    • Natural Product Sciences
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    • 제5권3호
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    • pp.148-150
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    • 1999
  • Seed lipids and proteins of Crotalaria juncea L were analyzed for fatty acids and amino acids respectively. Gas chromatographic analysis of the oil gave palmitic acid (16.01%), stearic acid (7.29%), oleic acid (14.41%), linoleic acid (54.44%) and linolenic acid (7.86%). The defatted seed cake contained all the essential amino acids except methionine and six non-essential amino acids.

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Effects of lactic acid bacteria and molasses on fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro ruminal fermentation of rice straw silage

  • Zhao, Jie;Dong, Zhihao;Li, Junfeng;Chen, Lei;Bai, Yunfeng;Jia, Yushan;Shao, Tao
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권6호
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    • pp.783-791
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    • 2019
  • Objective: This study was to evaluate the fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro gas production of rice straw ensiled with lactic acid bacteria and molasses. Methods: Fresh rice straw was ensiled in 1-L laboratory silos with no additive control (C), Lactobacillus plantarum (L), molasses (M) and molasses+Lactobacillus plantarum (ML) for 6, 15, 30, and 60 days. After storage, the silages were subjected to microbial and chemical analyses as well as the further in vitro fermentation trial. Results: All additives increased lactic acid concentration, and reduced pH, dry matter (DM) loss and structural carbohydrate content relative to the control (p<0.05). The highest organic acid and residual sugar contents and lignocellulose reduction were observed in ML silage. L silage had the highest V-score with 88.10 followed by ML silage. L and ML silage improved in vitro DM digestibility as compared with other treatments, while in vitro neutral detergent fibre degradability (IVNDFD) was increased in M and ML silage (p<0.05). M silage significantly (p<0.05) increased propionic acid (PA) content and decreased butyric acid content and acetic acid/PA as well as 72-h cumulative gas production. Conclusion: The application of ML was effective for improving both the fermentation quality and in vitro digestibility of rice straw silage. Inclusion with molasses to rice straw could reduce in vitro ruminal gas production.