• Advances in nano research
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• 제2권4호
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• pp.179-186
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• 2014

Indium-nitrogen co-doped zinc oxide thin films (INZO) were prepared on glass substrates in the atmosphere by ultrasonic spray pyrolysis. The aqueous solution of zinc acetate, ammonium acetate and different indium sources: indium (III) chloride and indium (III) nitrate were used as the precursors. After film deposition, different anneal temperature treatment as 350, 450, $550^{\circ}C$ were applied. Electrical properties as concentration and mobility were characterized by Hall measurement. The surface morphology and crystalline quality were characterized by SEM and XRD. With the activation energy analysis for both films, the concentration variation of the films at different heat treatment temperature was realized. Donors correspond to zinc related states dominate the conduction mechanism for these INZO films after $550^{\circ}C$ high temperature heat treatment process.

• Corrosion Science and Technology
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• 제7권1호
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• pp.35-39
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• 2008

We have been studying application of electrochemical noise (Fluctuation) analysis for localized corrosion. Foils of Zinc, Aluminum and Magnesium were used as specimens for electrochemical cell simulating localized corrosion. These specimens were dipped in sodium chloride solutions adjusted to each exponent of Hydrogen ion concentration (pH) condition of 5.5, 10, 12 respectively. Time variations of potential and current were measured in those solutions, and simultaneously the surfaces of specimens were observed using microscope with television monitor. Two types of electrochemical cells were arranged for experiments simulated localized corrosion. The fluctuations on trendy component of short-circuited potential and short-circuited current were appeared in synchronization. It was seemed that these fluctuations result from hydrogen evolution on the aluminum active site in the crevice from the microscopic observation. In the case of zinc and magnesium, fluctuations appeared on the trendy component of the corrosion potential. Two types fluctuation were detected. First one is the fluctuation varied periodically. The second one is the random fluctuation. It was seemed that these fluctuations result from generation of corrosion products and hydrogen evolution on the active site in the crevice of zinc and magnesium from the microscopic observation.

• Corrosion Science and Technology
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• 제16권2호
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• pp.69-75
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• 2017

Zinc coating on carbon steels give the higher corrosion resistance in chloride containing environments and in carbonated concrete. However, hydrogen evolution accompanies the corrosion of zinc in the initial activity in fresh concrete, which can lead to the formation of a porous structure at the reinforcement -concrete interface, which can potentially reduce the bond-strength of the reinforcement with concrete. The present study examines the mechanism of the corrosion of hot-dip galvanized steel in detail, as in the model pore solutions and real concrete. Calcium ion plays an important role in the corrosion mechanism, as it prevents the formation of passive layers on zinc at an elevated alkalinity. The corrosion rate of galvanized steel decreases in accordance with the exposure time; however, the reason for this is not the zinc transition into passivity, but the consumption of the less corrosion-resistant phases of hot-dip galvanizing in the concrete environment. The results on the electrochemical tests have been confirmed by the bond-strength test for the reinforcement of concrete and by evaluating the porosity of the cement adjacent to the reinforcement.

• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.28-34
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• 2023

Endoribonuclease YbeY is specific to the single-stranded RNA of ribosomal RNAs and small RNAs. This enzyme is essential for the maturation and quality control of ribosomal RNA in a wide range of bacteria and for virulence in some pathogenic bacteria. In this study, we determined the crystal structure of YbeY from Staphylococcus aureus at a resolution of 1.9 Å in the presence of zinc chloride. The structure showed a zinc ion at the active site and two molecules of tricarboxylic acid citrate, which were also derived from the crystallization conditions. Our structure showed the zinc ionbound local environment at the molecular level for the first time. Molecular comparisons were performed between the carboxylic moieties of citrate and the phosphate moiety of the RNA backbone, and a model of YbeY in complex with a single strand of RNA was subsequently constructed. Our findings provide molecular insights into how the YbeY enzyme recognizes singlestranded RNA in bacteria.

• 미생물학회지
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• 제8권1호
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• pp.41-51
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• 1970

S.albus subsp.와 S.globosus에서 Tetracyclin과 Streptomycin 같은 항생물질을 생성된다는 것은 이미 전보에서 밝힌 바 있다. 이들 두 種의 생장최적조건과 항생제 생성정도와의 관계를 배지성분과 그 농도에 따라 검토하였다. 그 결과 S.albus subsp.와 S.globosus 모두 배양시간이 130~150시간이 될때 항생물질 생성과 균체량이 최고에 달했다. 그리고 PH는 그 근처에서만 떨어지는 현상을 볼 수 있었다. 또한 두 균주 모두 탄소원으로서는 starch(4~5%)질소원으로서는 soybeam meal(1.5~2.0%)에서 균체의 생장도 양호하고 향균력도 높게 나타났다. 이외의 성분으로는 calcium carbonate(2mg/ml), potassium phosphate' dibasic(0.05M~0.01M), magnesium sulfate(0.01M~0.03M) ferric chloride(0.01M)가 가장 생장에 좋은 배지농도로 추정되며 zinc ion(0.0005M)은 균체생장을 현저하게 억제하였다.

• 한국토양비료학회지
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• 제5권1호
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• pp.41-47
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• 1972

우리나라 보은(報恩), 필리핀의 Batangas 토양(土壤)을 공시(供試)로 하여 수도생육(水稻生育)에 있어서 아연결핍(亞鉛缺乏)에 관(關)한 시험(試驗)을 국제미작연구소(國際米作硏究所)(IRRI)에 연구(硏究)한 결과(結果)는 다음과 같다. 1. 한국(韓國)의 보은토양(報恩土壤)은 산성(酸性)이며 유기물(有機物) 함량(含量)이 적고 수도체내(水稻體內)의 아연함량(亞鉛含量)도 33ppm인 정상적(正常的)인 토양(土壤)이고 비율빈(比律賓)의 Batangas 토양(土壤)은 Alkali며 토양유기물(土壤有機物)이 많고 Ca함량(含量)이 많은 Ca Calareous 토양(土壤)이고 수도체내(水稻體內)의 아연함량(亞鉛含量)도 16ppm으로 심한 아연결피증(亞鉛缺乏症)을 보였다. 2. 수도체내(水稻體內)의 아연분포(亞鉛分布)는 생육(生育)이 왕성(旺盛)한 상위엽(上位葉)에 많이 축적(蓄積)된다. 수도체내아연함량(水稻體內亞鉛含量)이 18ppm 이하(以下)이면 아연결핍(亞鉛缺乏)을 나타낼 우려가 있다. 3. 아연결핍(亞鉛缺乏) 토양(土壤)에는 요소질비료(窒素質肥料)로써 생리적산성비료(生理的酸性肥料)인 유안(硫安)이 좋고 요소(尿素)는 적합(適合)치 않았다. 4. 수도체내(水稻體內)의 Zn 다량흡수(多量吸收)는 Mn 흡수(吸收)를 조해(阻害)하며 수도체내(水稻體內)의 Mn/Zn 비(比)가 클수록 아연결핍(亞鉛缺乏)을 촉진(促進)한다. 5. 아연결핍토양(亞鉛缺乏土壤)인 Batangas 토양(土壤)에 $ZnCl_2$와 F.T.E의 시용효과(施用效果)가 컸으며 수확량(收穫量)은 대비구(對比區)에 비(比)해 유의성(有意性)있게 증수(增收) 되었다.

• 대한약침학회지
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• 제14권2호
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• pp.5-14
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• 2011

Objectives: Fibrinolytic enzyme preparations were isolated from the snake venom of Macrovipera lebetica turanica in this study. Methods: The purity of the preparations was determined using SDS-PAGE and the enzymic characteristics of the purified fibrinolytic enzyme were determined. Results: 1. All of the two preparations with fibrinolytic activity obtained from the snake venom of M. l. turanicat contained the major polypeptide with the molecular weight of 27,500. One of the preparation showed purified fibrinolytic enzyme. 2. The purified fibrinolytic enzyme hydrolyzed ${\alpha}$-chain of fibrinogen faster than ${\beta}$-chain but not ${\gamma}$-chain. 3. The fibrinolytic activity was inhibited completely by EDTA, EGTA, 1,10-phenanthroline, and dithiothreitol. 4. The fibrinolytic activity was inhibited completely by calcium chloride, iron(III) chloride, mercuric chloride, and cobalt (II) chloride. 5. The fibrinolysis zone formed after addition of zinc sulfate was smaller but clearer than the control. Conclusions: These results suggested that the fibrinolytic enzyme purifed from the snake venom of M. l turanica was a metalloprotease containing dithiol group.

• Asian-Australasian Journal of Animal Sciences
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• 제17권7호
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• pp.1007-1013
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• 2004

This experiment was conducted to investigate the effect of cadmium levels on weight gain, nutrient digestibility and the retention of iron, copper and zinc in tissues of growing pigs. A total of one hundred and ninety-two crossbred pigs (barrows, Duroc$\times$Landrace$\times$Yorkshine, 27.67$\pm$1.33 kg of average initial body weight) were randomly allotted to four treatments. Each treatment had three replicates with 16 pigs per pen. The corn-soybean basal diets were supplemented with 0, 0.5, 5.0, 10.0 mg/kg cadmium respectively, and the feeding experiment lasted for eight-three days. Cadmium chloride was used as cadmium source. The results showed that pigs fed the diet containing 10.0 mg/kg cadmium had lower ADG and FCR than any other treatments (p<0.05). Apparent digestibility of protein in 10.0 mg/kg cadmium-treated group was lower than that of other groups (p<0.05). There was lower iron retention in some tissues of 5.0 mg/kg and 10.0 mg/kg cadmium treatments (p<0.05). However, pigs fed the diet 10.0 mg/kg cadmium had higher copper content in most tissues than that of any other groups (p<0.05). There was a significantly increase of zinc retention in kidney of 10.0 mg/kg cadmium additional group (p<0.05) and zinc concentrations in lymphaden, pancreas and heart of 10.0 mg/kg cadmium treatment were lower than those of the control (p<0.05). This study indicated that relatively high cadmium level (10.0 mg/kg) could decrease pig growth performance and change the retention of iron, copper and zinc in most tissues during extended cadmium exposure period.

• 분석과학
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• 제13권6호
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• pp.699-704
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• 2000

도금폐수중의 시안이온의 전기화학적 분해 및 아연이온의 제거에 관한 연구를 백금으로 도금된 티타늄 양극과 스텐레스 음극 전극을 사용하여 수행하였다. 전기분해시간, 셀전류, 첨가제, 염화물농도등의 여러 가지 실험파라메터를 연구하여 도금폐수중의 시안화물 분해 및 수용액중의 아연이온의 효과적인 제거에 사용하였다. 셀전류와 첨가제의 종류에 따라 시안이온의 분해 및 아연이온의 제거 효율이 크게 영향을 받는 것이 발견되었다. 시안이온의 분해 및 아연이온의 제거를 위한 경제적이며 높은 효율을 나타내는 최적화된 조건은 1시간의 전기분해시간, 12A의 전류, 그리고 0.5 M NaCl 첨가제를 사용하여 확립하였다. 양극에서의 시안이온의 분해에 관한 반응메카니즘도 논의하였다.

• 동아시아식생활학회지
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• 제26권4호
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• pp.314-324
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• 2016

To improve the color stability of chlorophyll in young barley leaf used as functional green biomaterial, the absorption spectrum, color values, and antioxidative activities of young barley leaf (YBL) treated with zinc ion solutions were investigated. The small pieces of fresh YBL in aqueous solution mixtures were autoclaved twice at $110^{\circ}C$ for 30 min (pH 5). Distilled water (BLA), 0.01% zinc chloride (BLAZ), 0.01% zinc citrate (BLAC), and 0.01% zinc lactate (BLAL) solutions were used. Treated YBL powders were extracted with 80% EtOH for 4 h. Chlorophyll a and b contents differed with different treatments. BLA decreased chlorophyll a and b contents, whereas others were maintained. Absorbance spectrums of chlorophyll at 400~700 nm showed different maximum peak wavelengths. After heating in acidic and neutral solutions (pH 3, 5, and 7), the colors of YBL and BLA changed from green to olive green, whereas BLAZ, BLAC, and BLAL remained green color. The antioxidative activities showed higher values in YBL extract than in treated extracts. From the above results, autoclaved YBL in zinc solution would increase the color stability and maintain green color regardless of acid and heat treatments.