• 제목/요약/키워드: glacial acid

검색결과 42건 처리시간 0.027초

남극 사우스셰틀란드 킹죠지섬 바톤반도 빙하쇄설물의 화학적 풍화작용: 미조직학적 증거 (Chemical Weathering of Glacial Debris of the Barton Peninsula of King George Island, South Shetland Islands, Antarctica: Microtextural Evidences)

    • 한국광물학회지
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    • 제16권2호
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    • pp.181-189
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    • 2003
  • 킹죠지섬에 분포하는 빙하쇄설물의 화학적 풍화작용의 유무를 탐색한 결과, 다양한 풍화조직들과 이차광물들이 관찰되었다. 지표에 노출된 안산현무암질 응회암 각력에는 방해석이 선택적으로 용해되어 형성된 풍화테들이 형성되어 있다. 풍성화산유리의 가장자리에는 Al, Fe, Ti가 상대적으로 농집된 매우 얇은 용탈층이 존재하며, 앨로패인과 철산화물 등으로 구성되어 있다. 화강섬록암 지역의 흑운모는 질석과 흑운모-질석 혼합층으로 변질되었으며 드물게 아주 미량의 캐올리나이트나 깁사이트가 생성되었다. 열수변질대 지역의 황철석은 산화철로 풍화되었으며, 주변의 녹니석은 부분적으로 팽윤성광물로 풍화되었다. 그러나 사장석과 K장석 등은 거의 변질되지 않았다. 바톤반도의 빙하쇄설물은 미약하나마 화학적 풍화작용을 받아 앨로패인과 산화철 등의 이차광물이 생성되고 있으나, 킹죠지섬 주변 해양 퇴적물에 풍부한 스멕타이트의 대량 생성은 관찰되지 않았다.

치과용 비귀금속합금의 식각표면에 대한 주사전자현미경적 연구 (Scanning Electron Micrographic Study on the Etched Surface of Base Metal Alloys for Dental Restorations)

  • 정헌영;이선형
    • 대한치과보철학회지
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    • 제23권1호
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    • pp.83-95
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    • 1985
  • The purpose of this study was to evaluate microstructures on the etched surface of 11 base metal alloys for dental restorations and to observe the relationship between the etching pattern and beryllium. For this purpose, the following experiments were done; 11 base metal alloys were etched in (1) 10% $H_2SO_4$, (2) 10% $H_2SO_4$, 9 parts+methanol 1 part (3) Conc. $HNO_3$ 25%+glacial acetic acid 25%+$H_2O$ 50% (4) Conc. $HNO_3$ 5% (5) 2% glacial acetic acid added to Conc. $HNO_3$ 1% solution, with their etching conditions varied. Etched surface of alloys were examined under the scanning electron microscope. Results were as follows; 1. Almost all of Ni-Cr-Be alloys showed gooed etchd surface in $H_2SO_4$, solution, while some of those alloys which contains no beryllium showed good etched surface in $HNO_3$ solution. 2. Main components of etching solution can vary etching pattern of alloys. 3. Gamma prime phase relief, which can be found in all Ni-Cr-Be alloys, can't be found in any alloy that contains no beryllium.

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An Etiology Report for Burns Caused by Korean Folk Remedies

  • Hong Sil Joo;Hyun Been Kim
    • Archives of Plastic Surgery
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    • 제50권3호
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    • pp.305-310
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    • 2023
  • Background In this modern era of science-based medicine, some people still accept folk remedies as an alternative form of medicine. However, misinformation and misuse of folk medicines can result in dangerous complications. Among the possible complications of folk remedy use, this study focused on the clinical characteristics of burns caused by folk remedies. Methods We retrospectively reviewed the clinical records of patients who had been treated for burns caused by folk remedies from May 2015 to April 2022. Data were collected on patients' age and gender, type of folk remedy, reason for using the folk remedy, the severity of the burn, the number of wounds, lesion type, and type of treatment. Results We found 59 patients with burns due to folk remedies. Most were female (76.3%) and ≥ 60 years old (72.9%). The most common type of folk remedy was moxibustion (74.6%), followed by the use of glacial acetic acid (20.3%). The reasons for using folk remedies were arthralgia relief (39%), health improvement (18.6%), and treatment of tinea pedis (11.9%). Most patients had multiple wound sites and had burns that were considered severe, requiring surgical treatment (72.9%). The majority of lesions were on the lower extremity, including the foot. Conclusion This study described the risk of burns caused by folk remedies and the clinical characteristics of the wounds. The results emphasize the need for greater public awareness of the risk of burn injuries when using folk remedies.

Ethyl 1-Aminotetrazole-5-carboxylate로부터 유도된 헤테로고리 화합물들의 항균 활성 시험 (Antimicrobial Assessment of Some Heterocyclic Compounds Utilizing Ethyl 1-Aminotetrazole-5-carboxylate)

  • Taha, Mamdouh A. M.;El-Badry, Susan M.
    • 대한화학회지
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    • 제54권4호
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    • pp.414-418
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    • 2010
  • Ethyl 1-aminotetrazole-5-carboxylate (1)를 hydrazine hydrate와 반응시켜서 대응하는aminohydrazide 2를 합성한 후에, 화합물 2를carbon disulfide와 반응시켜서 1,3,4-oxadiazole-5-thiol structure 3을 합성하였다. 얻어진 화합물 3을 either chloroacetone 또는 ethyl chloroacetate와 반응시켜서S-acyl 1,3,4-oxadiazole 유도체인 4 와 5를 합성하였으며, 또한 hydrazine hydrate와 반응시켜서 4-amino-1,2,4-triazole-5-thiol 유도체인 6을 합성하였으며, 화합물 6을 glacial acetic acid와 반응시켜서 6-methyl-1,3,4-triazolo[3,4-b]-1,3,4-thiadiazole (7)을 합성하였다. 한편, 알려진 방법에 따라서, 화합물 1로부터 tetrazolo[5,1-f]-1,2,4-triazine 9을 얻은 다음에, 화합물 9를 carbon disulfide와 반응시켜서 8-thione 유도체인 10을 합성한 후에, 대응하는 화합물 11, 12 및 13을 합성하였다. 얻어진 화합물13을 이용하여1,2,4-triazolo[4,3-d]tetrazolo[5,1-f]-1,2,4-triazines 14와 15를 합성하였다. 새롭게 합성한 화합물들의 화학구조를 확인하였으며, 합성한 화합물들에 대한 항균 활성시험을 수행하였다.

Preparation and Evaluation of Bupivacaine-loaded Microspheres by Solvent Extraction Method

  • Kim, Min-Soo;Hwang, Sung-Joo
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.299.2-300
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    • 2003
  • Various bupivacaine-Ioaded microspheres were prepared with poly (d,l-Iactide) (PLA) by solvent extraction method. The internal solution of polymer(PLA R104) and drug in glacial acetic acid was introduced into the external phase of polyvinylpyrrolidone (PVP K-30) in polyethyleneglycol (PEG), and emulsified to be an oil-in-oil (o/o) emulsion. The o/o emulsion was poured to the buffer solution. (omitted)

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액상한약제제의 보존제 모니터링 (Monitoring of preservatives in herbal liquid preparations)

  • 전종섭;조현례;김범호;조상훈;박신희;김영숙;윤미혜;이정복
    • 분석과학
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    • 제24권2호
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    • pp.127-134
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    • 2011
  • 본 연구에서는 기존 대한약전외 일반시험법 중 파라옥시안식향산에스텔 및 그 염류의 함량시험법의 이동상의 조성을 acetonitrile water (containing 1% glacial acetic acid) mixture (30:70 v/v)로 변화시켜 첨가제로 사용된 보존제성분과 제품에서 기인하는 방해물질과의 완전한 분리를 통하여 액상한약제제 분석의 효율성을 기하였다. 유통되고 있는 한약제제 중 액상제품 총 47품목을 대상으로 안식향산나트륨, 디히드로 초산나트륨, 파라옥시안식향산메칠, 파라옥시안식향산에칠, 파라옥시안식향산프로필 등 5종의 함량을 모니터링 하였다. 그 결과 액상한약제제 37품목 중 보존제가 표시된 31품목은 보존제가 표시된 함량에 맞게 함유되어 있었다. 안식향산과 디히드로초산이 함유된 7품목 중 6품목은 디히드로초산이 표시량에 비해 낮게 검출되었거나 검출되지 않았다. 보존제가 미표시된 10품목 중 3품목에서 보존제가 검출되었다. 3건 모두 안식향산이 검출되었고 그 중 2건에서 디히드로초산이 검출되었으며 1건에서 메틸파라벤이 검출되었다.

Acetate-Promoted Aldol-Type Reaction: Scope and Reactivity of Acetates and Aldehydes

  • Kim, Dong-Hyeon;Rahman, A. F. M. Motiur;Jeong, Byeong-Seon;Lee, Eung-Seok;Jahng, Yurng-dong
    • Bulletin of the Korean Chemical Society
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    • 제30권4호
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    • pp.797-802
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    • 2009
  • Potential of acetates and related compounds in glacial acetic acid as a catalyst for aldol-type condensation reactions was examined. Reactions of cycloalkanones or selected heteroaromatics with aldehydes in presence of 10 mol% of various acetates in acetic acid afforded ${\alpha},{\alpha}$'-bis(substituted-benzylidene)cycloalkanones and substituted-benzylidene-mackinazolinones, respectively, in good yields. Among the compounds tested, ammonium acetate is the best and effective especially towards the reactions of mackinazolinone and aliphatic aldehydes to afford 6-alkylidenemackinazolinones.

Effects of Chitosan on Production and Rot Control of Soybean Sprouts

  • Lee, Young-Sang;Kang, Chang-Sung;Lee, Yong-Sun
    • 한국작물학회지
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    • 제44권4호
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    • pp.368-372
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    • 1999
  • The practicality of utilizing chitosan as a natural antimicrobial compound to reduce soybean sprout rot was tested. Domestic and imported soybean seeds were soaked for 6 hours in solutions containing different levels of chitosan and acetic acid (glacial), and cultured at $25^{\circ}C$ for 6 days. In case of domestic seeds, soaking with 1,000ppm chitosan increased germination percentage, hypocotyl thickness, total length, and fresh weight of sprouts by 4%, 5%, 2%, and 1%, respectively. The total sprout yield was increased by chitosan in a concentration-dependent manner in that 1,000ppm chitosan resulted in 8% increment of total yield (7.47kg sprouts/kg seed). Chitosan significantly reduced sprout rot percentage to 7.0% compared to control (13.8%), and consequently enhanced marketable sprout yield by 39%. Compared to domestic seeds, the imported soybean seeds exhibited very low germination percentage regardless of chitosan treatments. Chitosan, nevertheless, consistently induced yield increment and rot decrement in imported soybean sprouts. Although 100ppm acetic acid was effective in reducing sprout rot percentage down to 11.8%, its yield-increasing effects were not as prominent as chitosan. In conclusion, soaking soybean seeds with chitosan seems to be a practical method to enhance the efficiency of soybean sprout production.

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고온, 한냉 및 산도가 토끼 적혈구막 투과성에 미치는 영향 (Influence of Heating, Cooling and Acidity on the Permeability of the Rabbit Erythrocyte Membrane)

  • 이덕숙;신효숙;황애련;최덕경
    • The Korean Journal of Physiology
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    • 제1권2호
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    • pp.151-156
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    • 1967
  • Outward movement of hemoglobin and $K^+$ ion across rabbit erythrocyte membrane after heating, cooling and in acid medium was studied. One milliliter of rabbit blood was centrifuged and packed red cells were obtained. Packed red cells were resuspended by addition of 4 ml of 0.9% NaCl solution and were subjected to heating $(57^{\circ}C\;for\;5\;minutes)$ or cooling $(-4^{\circ}C{\sim}-8^{\circ}C\;of\;-10^{\circ}C{\sim}-11^{\circ}C\;for\;10\;minutes) $. For acid medium experiment packed ref cells were resuspended by addition of 4 ml of acid medium of PH 4.5 consisting of 0.01% glacial acetic acid in 0.85% NaCl solution and kept standing for 10 minutes. All red cell suspensions were centrifuged again and packed red cells were separated. This packed red cells were again suspended in 4 ml of NaCl solution of 0.8%, 0.7%, 0.6%, and 0.5% concentration respectively and kept standing for 20 minutes. The concentration of hemoglobin and $K^+$ in the supernatant of the above red cell suspensions were measured and the following results were obtained. 1. Outward movement of hemoglobin and $K^+$ was greatest in red cells subjected to heating. The movement paralled to the osmolal concentration gradient between extra- and intra-cellular phase of red cells. 2. In acid medium the outflux of hemoglobin and $K^+$ increased as compared to the control. 3. In red cells subjected to the cold of $-10^{\circ}C{\sim}-11^{\circ}C$ the outflux of hemoglobin and $K^+$ increased. Whereas in the environment of $-4^{\circ}C{\sim}-8^{\circ}C$ there was no change in the outflux of $K^+$. The he-moglobin outflux showed rather a decreased as compared to tile control.

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국내 시판되는 식초의 항산화 활성 (Antioxidant Activity of Vinegars Commercially Available in Korean Markets)

  • 이선미;최용민;김영화;김대중;이준수
    • 산업식품공학
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    • 제13권3호
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    • pp.221-225
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    • 2009
  • 본 연구에서는 국내에서 시판되고 있는 19종 식초 및 식초음료에 대해 항산화활성과 항산화성분의 함량을 측정함으로써 그 상관관계를 알아보고자 하였다. 총 폴리페놀 함량은 발사믹식초가 372.53mg/100mL로 가장 높았으며, 주로 음료용 식초가 조리용 식초보다 높은 함량을 나타내었다. 또한 총 플라보노이드 함량에서도 발사믹 식초가 114.40mg/100mL로 가장 높았으며, 주로 음료용 식초가 조리용 식초보다 높은 함량을 나타낸 반면에, 유기산 함량에서는 빙초산이 가장 높은 수치를 보였다. 본 연구에서 식초의 유기산 함량과 항산화 성분 활성은 상관관계가 없었으며 이는 식초의 유기산이 항산화활성에는 관여하지 않음을 알 수 있었다. 본 연구에서 항산화활성이 가장 높게 나타난 식초는 발사믹 식초였으며, 주로 음료용식초가 조리용식초보다 높게 나타났으며, 식초의 항산화활성에 주로 기여하는 물질은 폴리페놀 화합물로 생각된다.