• 제목/요약/키워드: Periodic acid

검색결과 194건 처리시간 0.029초

Aqueous Polymerization of Acrylamide Initiated by Periodic Acid and Its Kinetics

  • Cho, Myung-Rae;Han, Yang-Kyoo;Kim, Bum-Sung
    • Macromolecular Research
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    • 제8권4호
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    • pp.147-152
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    • 2000
  • The activity of periodic acid as an initiator for the polymerization of acrylamide in aqueous medium was investigated. The rate of polymerization was found to be proportional to the monomer concentration to the 1.5th power in the range of 1.41-5.64 mol/L. The reaction order to the periodic acid concentration was 0.49, which indicated a bimolecular mechanism for the termination reaction in the range of 0.5-4.0$\times$10$\^$-2/ mol/L. Propagation rate increased with raising the temperature according to an Arrhenius expression resulting in the exhibition of an apparent activation energy of 87.8 kJ/mol in the temperature range of 60-80$\^{C}$. The addition of hydroquinone as a radical scavenger stopped the polymerization of acrylamide initiated by periodic acid. These results support that the polymerization proceeds via a radical chain mechanism .

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백서 전치 주기적절제시 치수내 LDH ISOENZYME에 관한 연구 (LACTIC ACID DEHYDROGENASE ISOENZYME IN THE PERIODIC AMPUTATED RAT INCISOR PULP)

  • 최근배
    • 대한치과의사협회지
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    • 제10권1호
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    • pp.15-21
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    • 1972
  • 백서의 전치를 주기적으로 절제후 치수내의 LDH isoenzyme을 전기영동법으로 분리하고 그의 활성도를 측정하여 정상과 비교관찰한바 다음과 같은 결론을 얻었다. 1. 정상치수내에서 5개의 LDH isoenzyme의 존재를 확인하였다. 2. LDH 활성도는 주기적으로 절제한 치아의 치수가 정상치수에 비해 훨씬 증가하였다. 3. 치아를 주기적으로 절제함으로써 치수내 LDH isoenzyme의 Pattern을 변화시킬 수가 있다.

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Staining Characteristics of Mast Cell Tumor in a Hedgehog

  • Lee, Jong-Won;Han, Mi-Na;Kim, Gon-Hyung;Chang, Dong-Woo;Na, Ki-Jeong
    • 한국임상수의학회지
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    • 제33권4호
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    • pp.218-220
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    • 2016
  • A 2-year old female African hedgehog (Atelerix albiventris) weighing 645 grams was presented with a well circumscribed mass in the subcutaneous of the left shoulder. It measured $2{\times}2cm$ in size and had a hard texture. There were no clinical signs. In a fine-needle aspiration (FNA) cytological evaluation, mast cells were identified with Wright-Giemsa stain. Mast cell tumor was confirmed and characterized by surgical sampling and histopathological evaluation. Four stains (hematoxylin-eosin, toluidine blue, periodic acid-Schiff, and Safranin O) were examined in order to find an applicable stain for a mast cell tumor histopathological evaluation in hedgehog. This case showed that periodic acid-Schiff and toluidine blue staining were the most useful for assessment of a mast cell tumor in a hedgehog.

Pyridoxine 투여한 백서법랑질형성에 있어 조직화학적 인산반응에 관한 연구 (HISTOCHEMICAL PHOSPHORIC ACID REACTION ON AMELOGENESIS OF WHITE RAT APPLIED WITH PYRIDOXINE)

  • 김영식
    • 대한치과의사협회지
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    • 제10권4호
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    • pp.209-212
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    • 1972
  • The effect of pyridoxine on the incisors were histochemically studied for the purpose of identifying the phosphoric acid. The microscopic observations were carried out by means of phosphoric acid reaction(Serraet Queiroz-Lopes method), mucoprotein reaction (Clara method), periodic acid-Schiff reaction (McManus method), methylen blue stain and hematoxylin-eosin stain. In the experimental result, it was found that phosphoric acid reactions of ameloblast, Tomes' process and preenamel were remarkably increased after pyridoxine administration.

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압력구배의 주기적 변화에 따른 한외여과 Flux의 변화 (Response of Ultrafiltration Flux to Periodic Oscillations in Transmembrane Pressure Gradient)

  • 서창우;이은규
    • KSBB Journal
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    • 제14권2호
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    • pp.230-234
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    • 1999
  • 한외여과공정에서 압력구배를 주기적으로 변화시켜 막 표면의 용질층을 불안정화시켜 여과 flux의 총괄적 향상을 유도한 실험을 수행하였다. 일정압력에서의 여과 flux 감소현상을 Hernia 식을 사용하여 모사하였고, 또한 압력구배의 주기적 변화를 Fourer series로 표현하여 압력구배의 변화에 따른 flux 변화를 수학적으로 모사하였고 이 결과를 실제의 실험결과와 비교하여 보았다. 수학적 모사결과 압력변화의 형태, 진폭, 주기 등의 변화에 따른 평균 flux의 변화는 미미하였다. 하지만 실제실험결과 주기적으로 압력구배를 변화시킨 경우 약 11%의 향상을 관찰할 수 있었다. 이는 압력구배가 주기적으로 변하는 과정에서의 응질층의 압축이완속도가 다른 것에 기인하는 것으로 유추된다. 주기적 압력구배변화외에 feed pump interruption을 이용하여 평균총괄 flux를 약 32%까지 향상 시켰다. 역확산에 의한 용질층의 이완에는 일정한 시간이 필요함을 찾아내었고 interruption은 용질층이 형성되기 전부터 시작하는 것이 유리하다고 판단되었다. 본 실험을 위하여 한외여과의 자동제어 시스템을 설계제작하여 다양한 압력함수를 이용할 수 있었고, 공정운영 중 압력구매와 여과 flux를 실시간 모니터링 및 제어할 수 있었다. 자동제어 시스템을 통해 압력구매를 주기적으로 변화시켜 총괄 flux의 극대화를 도모하는 기법은 기존장치를 최소로 변경시키면서 한외여과성능을 극대화시킬 수 있는 방법으로 기대된다.

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진도견 정세관의 정세포와 Sertoli 세포내 glycogen의 분포 (Glycogen distribution of germ cells and Sertoli cells of seminiferous tubules in Jindo dog)

  • 박영석;이성호
    • 대한수의학회지
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    • 제36권3호
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    • pp.521-529
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    • 1996
  • In an effort to obtain basic data of carbohydrate metabolism during spermiogenesis of the sexually-matured Jindo dog, the glycogen distribution in the testis was investigated by light and transmission electron microscopy. Periodic acid thiocarbohydrazide silver proteinate physical development(PA-TCH-SP-PD) staining method provided better results in the detection of glycogen granules from Sertoli cells and germ cells than the periodic acid schiff(PAS) staining method did. Pre-treatment of the tissue sections with ${\alpha}$-amylase elicited a significant decrease in PA-TCH-SP-PD stained granules, which suggested that the stained granules were of glycogen origin. High concentration of the glycogen granules were observed in the Sertoli cells, especially in its column, sheet-like processes, club-like processes, and tubular processes. The glycogen granules were unevenly distributed in some Sertoli cell columns. These results strongly indicated that the Sertoli cells of Jindo dogs showed vigorous activity of carbohydrate metabolism.

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A Review of Wet Chemical Etching of Glasses in Hydrofluoric Acid based Solution for Thin Film Silicon Solar Cell Application

  • Park, Hyeongsik;Cho, Jae Hyun;Jung, Jun Hee;Duy, Pham Phong;Le, Anh Huy Tuan;Yi, Junsin
    • Current Photovoltaic Research
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    • 제5권3호
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    • pp.75-82
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    • 2017
  • High efficiency thin film solar cells require an absorber layer with high absorption and low defect, a transparent conductive oxide (TCO) film with high transmittance of over 80% and a high conductivity. Furthermore, light can be captured through the glass substrate and sent to the light absorbing layer to improve the efficiency. In this paper, morphology formation on the surface of glass substrate was investigated by using HF, mainly classified as random etching and periodic etching. We discussed about the etch mechanism, etch rate and hard mask materials, and periodic light trapping structure.

한국재래산양의 큰침샘에 대한 형태학적 연구 (Morphological studies on the major salivary gland of the Korean native goat)

  • 김진상;이흥식;이인세;이성준
    • 대한수의학회지
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    • 제32권4호
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    • pp.463-479
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    • 1992
  • The morphological findings of the parotid, mandibualr and sublingual salivary glands of the Korean native goat have been investigated by the histological and histochemical observation using the light microscope. Tissues were fixed with 10% neutral buffered formalin and Bouin's solution, and embedded in paraffin. The tissue sections were stained with hematoxylin and eosin, Heidenhain's azocarmine-aniline blue, alcian blue, toluidine blue, periodic acid Schiff, aldehyde fuchsin, alcian blue-periodic acid Schiff and aldehyde fuchsin-alcian blue. Some sections were stained with the alcian blue after each teatment of diastase digestion, methylation, methylation-saponification, and neuraminidase digestion. The results were as follows ; 1. The major salivary glands were compound. tubuloacinar glands, and the parenchyma was composed of acini, intercalated ducts, striated ducts and excretory ducts. 2. The acini were composed of serous cells in the parotid gland, and mucous cells, serous cells and seous demilunes in the mandibular gland. The acini of the sublingual glands were composed of mucous cells and serous demilunes. 3. In histochemistry, the serous cells of the parotid gland contained neutral mucin and enzyme-liable silaic acid. 4. The serous cells and demilunes of the mandibular gland contained neutral mucin and enzyme-liable sialic acid, and the mueous cells contained sulfated mucin, enzyme liable sialic acid and neutral mucin 5. In the sublingual gland, the mucous cells contained sulfated mucin, enzyme-resistant sialic acid and neutral mucin, and the serous demilunes contained neutral mucin and enzyme-resistant sialic acid.

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