• Restorative Dentistry and Endodontics
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• v.28 no.5
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• pp.425-430
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• 2003

The purpose of this study was to evaluate the clinical applications of the Sodium Dichloroisocyanurate effervescent tablet as a routine root canal irrigant by performing several in vitro tests such as $Cl^{-}$ content. cytotoxicity. antimicrobial effect as well as its pH level compared to the equivalent concentration of sodium hypochlorite solution. 1. Sodium Dichloroisocyanurate demonstrated lower level of $Cl^{-}$ concentration than each dilution of sodium hypochlorite solution. Both solution has increased level of $Cl^{-}$ as the concentration of each solution increased. There was no significant change of $Cl^{-}$ concentration in sodium hypochlorite as time goes by. However. $Cl^{-}$ concentration in Sodium Dichloroisocyanurate was increased. 2. The antimicrobial effects of both solutions were increased when their concentrations were increased. One day after dilution. antimicrobial effect of Sodium Dichloroisocyanurate was slightly higher than sodium hypochlorite. however. there was no difference in 1 week dilution solution. One month dilution solution of sodium hypochlorite still retain its activity. but antimicrobial effect of Sodium Dichloroisocyanurate was drastically decreased 1 month after dilution. 3. The cytotoxicity of Sodium Dichloroisocyanurate was rather higher than same concentration of sodium hypochlorite solution until 1 week after dilution. Then in 1 month. cytotoxicity of Sodium Dichloroisocyanurate was decreased than that of 1 week dilution solution. especially 4% Sodium Dichloroisocyanurate solution has almost no toxicity. However. 1% and 2% sodium hypochlorite solution has unchanged moderate degree of cytotoxicity after the dilution. Furthermore. 4% sodium hypochlorite solution showed high level of toxicity. 4. The pH level of Sodium Dichloroisocyanurate showed that the solution was weak acid (pH5). On the other hand. sodium hypochlorite was revealed as a strong alkaline solution (pH12). There was no change in pH following the dilution of each solution. As results. Sodium Dichloroisocyanurate solution fully satisfy the basic requirements as a root canal irrigation solution. However. we strongly recommend to use this solution clinically in low concentration and try to apply into the root canal within 1 week after dilution.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.287-294
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• 2019

GGBFS(Ground Granulated Blast Furnace Slag) has been widely used in concrete for its excellent resistance chloride and chemical attack, however cracks due to hydration heat and dry shrinkage are reported. In many International Standards, GGBFS with low fineness of 3,000 grade is classified for wide commercialization and crack control. In this paper, the mechanical and durability performance of concrete were investigated through two mix proportions; One (BS) has 50% of w/b(water to binder) ratio and 60% replacement ratio with low-fineness GGBFS, and the other (TS) has 50% of w/b and 60% replacement ratio with 4000 grade and FA (Fly Ash). The strength difference between TS and BS concrete was not great from 3 day to 91 day of age, and BS showed excellent performance for chloride diffusion and carbonation resistance. Two mixtures also indicate a high durability index (more than 90.0) for freezing-thawing since they contain sufficient air content. Through improvement of strength in low fineness GGBFS concrete at early age, mass concrete with low hydration heat and high durability can be manufactured.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.310-315
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• 2019

This study conducted a series of studies to find alternative ways to use Chlorine Bypass System-dust(CBS-dust) in cement production. The results of engineering characteristics of CBS-dust are summarized as follows. First of all, the density of CBS-dust is 2.40, lighter than cement and the pH was 12.50 which was strong alkaline. In terms of particle size, it was 11.70 ㎛ which was finer than cement. With chemical properties, calcium oxide(CaO) was the highest as 35.10%, potassium oxide(K₂O) was 32.43%, potassium chloride(KCl) was 19.46%, sulfur oxide(SO₃) was 6.81%, and the remaining chemical components are SiO₂, Fe₂O₃, Al₂O₃, MgO, and the like. Therefore, if CBS-dust is used as early-strength chemical admixtures in the concrete secondary products that use a large amount of mineral admixtures without rebar, it can be an effective method for increasing the strength of concrete as an alkali activator and preventing early-frost damage of Cold Weather Concrete.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.235-244
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• 2020

This study conducted a series of studies to offer a novel method of using CBS-dust that produced as by-product in the manufacture of cement. Four different contents of BS and CBS-dust were adopted for test parameters of this study. Mortar with 50% of W/B was fabricated. First, in the case of the fresh mortar, the flow decreased as the CBS-dust replacement rate increased, but the binder composition ratio BS 45% and 65% showed higher fl ow than Pl ain when repl acing CBS-dust 5%. In the case of air content, overall, the tendency was proportional to the CBS-dust replacement rate, and chloride tended to exceed the reference value at all replacement rates except for the CBS-dust 0% replacement. The compressive strength of the hardened mortar shows the resul t that the strength is improved when the CBS-dust is repl aced by 5% to 10%, and the CSH gel and structure formation is confirmed by microstructure analysis through the hydration reaction when the CBS-dust is replaced. Therefore, for a given condition CBS-dust is used as a early-strength admixture in a concrete secondary product that uses a large amount of admixture without reinforcing bars it can be an effective method for enhancing the strength of concrete as an alkali activator.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.190-197
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• 2020

This paper evaluates the mechanical properties and durability of cement matrix blended with mineral admixtures and ferronickel slag(FNS) powder which is an industrial b y-product during ferronickel smelting process. The hydration heat, pore structure, compressive strength, length change, rapid chloride penetration test(RCPT), and freezing and thawing resistance of ternary blended cement matrix were investigated and compared with ordinary portland cement matrix. The result showed that the compressive strength of ternary blended cement matrix using ferronickel slag powder and mineral mixture was low in strength compared to the reference concrete, but recovered to a certain extent by using alkali activator. Length change of cement mortar using FNS powder have shown less shrinkage occurs than the reference specimen. In addition, irrespective of using the alkali-activators, all ternary mix are indicative of the 'very low' range for chloride ion penetrability according to the ASTM C 1202, and the freeze-thaw resistance also showed excellent results.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.407-416
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• 2008

본 연구는 CaCl2 용액의 주사량이 품종별 암사슴의 뿔 발생 유도에 미치는 영향을 구명하기 위하여 꽃사슴, 레드디어 및 엘크 암컷 각 6두에 대해 30% CaCl2 용액의 주사량을 1ml?, 1.5ml? 및 2ml?의 3처리구로 나누어 전두골 좌, 우 양쪽 골막에 3월과 7월 두 차례 주사한 후 사슴뿔 발생 유도율, 사슴뿔 생산량, 발육성적을 조사하였다. 품종별 암사슴의 뿔 발생은 꽃사슴이 1ml? 처리구의 한 마리 한쪽에서만 발생하였고, 레드디어는 2ml? 처리구의 한 마리 한쪽에서만 유도되어 꽃사슴과 레드디어의 뿔 발생 유도율은 8.3%였다. 엘크 암사슴은 1ml? 처리구에서는 뿔 발생이 일어나지 않았으며, 1.5ml?와 2ml? 처리구에서는 모두 뿔 발생이 유도되어 유도율은 67%였다. 뿔 생산량은 꽃사슴의 경우 길이 21cm?이고 무게 70g 이었으며, 레드디어는 길이 18.5cm?에 무게 83g의 뿔을 생산하였다. 엘크는 3월 1.5ml? 처리구의 길이가 평균 34±3cm?이었고 무게는 526~1,008g이며, 2ml? 처리구는 길이가 평균 39±8cm?, 무게는 693~1,379g의 범위에 있었다. 엘크의 2ml? 처리구는 7월에 주사한 것이 뿔 길이와 뿔 생산량에서 3월의 것보다 적었다. 암사슴 뿔의 발육은 엘크의 경우 주사 후 20일경에 길이 0.5~1cm? 정도의 돌기로 자랐고, 40일까지는 유발된 상처와 함께 1~3cm?정도의 완만한 성장을 보였다. 본격적인 성장은 처리 후 60일경이 지나야 일어났고, 120일경에 절각을 하였을 때 뿔 길이는 28~44cm?의 범위에 있었다. 생산된 암사슴 뿔을 세로로 절단하였을 때 전체 길이의 위쪽 70%는 골화가 되지 않은 상태였다. 암사슴의 뿔 발생 유도는 번식성적에는 전혀 영향을 미치지 않았다. 봄에 처리한 사슴의 재생 뿔 발생은 불규칙하게 일어났고, 재생 뿔 발생률은 평균 45%였으며, 주기가 진행될수록 길이와 생산량은 줄어드는 경향을 보였다. 결론적으로 30% CaCl2 용액의 주사량을 조절하여 처리하면 꽃사슴, 레드디어 및 엘크의 암컷에서 뿔 발생을 유도할 수가 있으며, 엘크 암사슴의 뿔 발생 유도를 위한 최적 주사량은 1.5~2ml? 범위였다.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.223-227
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• 2003

Survey on plant diseases occurring on cucumber cultivated in plastic film house of experimental farm in Suwon was conducted. Through the survey, occurrence of damping-off, downey mildew, powdery mildew and Fusarium wilt was observed. Especially downey mildew caused by Pseudoperonospora cubensis was the most severe foliar disease of cucumber. To control the disease effectively, effects of installation of ventilation fan and optimal spray timing of a chemical, dimethomorph+copper oxychloride WP, were investigated. Two ventilation fans installed at the front and at the back of plastic film house reduced air relative humidity by about 6.4% and downey mildew incidence by 55.7%. Downey mildew incidence on cucumber from untreated chemicals plot in plastic film house installed with ventilation fan was on a equal level with that from treated chemicals plot with three times application of dimethomorph+copper oxychloride WP in plastic film house without ventilation fan. Meanwhile in order to select optimal chemical application time, dimethomorth+copper oxychloride WP was treated three times at 7 days-interval from three days before the disease occurred, right after the disease occurred, and two days after the disease occurred, respectively. The result showed that dimethomorth+copper oxychloride WP applied to cucumber leaves and stems from three days prior to, right after, two days after occurrence of downey mildew reduced downey mildew incidence by 72.9, 61.8, and 23.7%, respectively. The above results showed that regulation of environmental factors like air relative humidity and preventive application of chemicals should be considered to establish control strategy to downey mildew.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.26-32
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• 2001

[ ${\alpha},{\beta}$ ]-Unsaturated carboxamides 12 with trifluromethylated dihydro-1,4-dithiins were synthesized for the purpose of development of new agrochemical fungicide. Chlorination of trifluoromethylated ${\beta}$-ketoester 4 followed by tile reaction with 1,2-ethanedithiol gave intermediate 1,4-dithiane 9. Without purification of 9 substitution of hydroxy by chlorine followed by dehydrochlorination in the presence of triethylamine afforded trifluoromethylated dihydro-1,4-dithiin ethyl ester 7. Activation of the hydroxy of the carboxylic acid 10 obtained from the hydrolysis of 7 and then reacted with various amines gave the corresponding trifluoromethylated dihydro-1,4-dithiin carboxamides. Antifungal screening (in vivo) against typical plant diseases, Rice Blast, Rice Sheath Blight, Cucumber Gray Mold, Tomato Late Blight, Wheat Leaf Rust, and Barley Powdery Mildew of the synthesized compounds was carried out. As a result, most of the compounds shlowed weak antifungal activities and some compounds in which isopropyl group was substituted in meta of the phenyl showed antifungal activity (99%) at 250 ppm against the disease Wheat Leaf Rust.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.47-53
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• 2015

Various diseases occur in fruits, leave and roots during strawberry cultivation and cause severe economical damage and huge amount of chemical fungicide use. Recently, as consumers' interest in safety of foods and organic agriculture produces have increased, control measures using alternatives for chemical fungicides have been newly developed in various ways. This study was conducted to test antifungal activity and control effect of sodium dichloroisocyanurate (NaDCC), using as disinfectants, against major disease pathogens of strawberry, Fusarium oxysporum (Fusarium wilt), Colletotrichum gloeosporioides (Anthracnose) and Phytophthora sp. (Phytophthora blight), and Xanthomonas fragariae (bacterial angular leaf spot) and evaluate availability as environment-friendly materials. When NaDCC was treated at the concentration range of 150 to 300 ppm, it suppressed significantly hyphal growth and reduced spore germination by more than 28%. In field condition, NaDCC showed excellent control effect (control value: 50%) against the bacterial angular leaf spot disease. Based on above-described results, we suggested that NaDCC can be used as alternative candidates to chemical pesticide alternatives of for controlling strawberry diseases.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.99-105
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• 2010

This paper investigated the characteristics of wasteform containing a spent zeolite used as a separating agent of FPs for recycling LiCl waste which would be generated from pyrochemical process of spent PWR fuel. In this study, a conventional borosilicate and Ca-rich glass were used as a consolidating agent for spent zeolite and it's mixing ratio was changed in the range, $25{\sim}35wt%$. The leach rates of Cs and Sr had about $0.1{\sim}0.01g/m^2day$ and $0.001{\sim}0.0001g/m^2day$, respectively. The leach resistance of Cs increased with amount of SAP and it showed about 10 times higher in the Ca-rich glass wasteform than in the conventional borosilciate glass wasteform. The compressive strength of wasteform was affected with the amount of glass. Thermal expansion rate of containing 30wt% glass has relatively lower than others. Also, the melting temperature was little changed in given mixing ratio of glass.