• 한국건설순환자원학회논문집
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• 제10권4호
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• pp.411-419
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• 2022

본 연구에서는 탄소나노튜브를 혼입한 경량·고강도 시멘트 독합체의 유해성을 평가하기 위해 급성경구독성시험 및 급성경피 독성시험을 실시하고, 이를 재령 28일 압축강도 50 MPa 수준의 탄소나노튜브를 혼입하지 않은 일반 콘크리트의 유해성과 비교하였다. 일반 콘크리트 및 탄소나노튜브를 혼입한 경량·고강도 시멘트 복합체 모두 급성경구독성시험결과 GHS category 5인 것으로 조사되었다. 또한, 모든 시편에서 급성경피독성시험에서 독성증상은 관찰되지 않았으며, GHS category 5/미분류(unclassified)에 해당하는 것으로 판단된다.

• 환경생물
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• 제23권1호
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• pp.89-92
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• 2005

빙어(Hypomesus olidus)를 사용하여 시멘트 농도에 따른 반수치사농도 (LC/sub 50/), 안정농도 (safe concentration) 및 적용계수 (application factors of pollutant)를 조사하였다. 실험어는 평균체장 8.6±1.2cm의 성어를 사용하였으며, 1주일 이상 안정시킨 후에 50L의 FRP 사각수조를 이용하여 시멘트 농도를 0 (대조구), 10, 25, 50, 100, 250, 500 및 1,000ppm로 설정하고 각 실험구에 30마리씩 수용하였다. 시멘트에 대한 빙어의 급성독성은 500ppm 이상의 농도에서 4시간 이내에 전량 폐사하였다. 그리고 시멘트 독성에 대한 반수치사농도(LC/sub 50/)는 48h-LC/sub 50/은 123.03 ppm, 72 h-LC/sub 50/은 91.20 ppm 및 96 h-LC/sub 50/은 58.88 ppm으로 각각 조사되었다. 또한 안정농도는 2.64∼9.14 ppm (평균 5.88 ppm), 적용계수는 0.045∼0.155(평균 0.100)로 각각 조사되었다.

• 한국환경복원기술학회지
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• 제13권1호
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• pp.57-68
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• 2010

The purpose of this study is to analyze the characteristics of environment-friendliness of waterproof materials based on comprehensive experiments on waterproofness in terms of coefficients of permeability, harmfulness of waterproof materials and fish toxicity of Oryzias latipes mortality to verify eco-toxicity of each method of construction and waterproof material, which are to be applied by taking eco-toxicity into account when building ecological flows in upper areas on natural and artificial grounds. As a result, the following conclusions have been reached in this study: 1. In regard of the harmfulness analyzed, each material showed a different result of analytical value in each lab tank. Compared to input water, pH, COD, SS, T-P, and T-N values increased a little, but DO value decreased. The value of turbidity analyzed independent of the water quality standard of aquatic ecosystem set forth by the Ministry of Environment increased a little compared to the value in input water. 2. In the experiment of fish toxicity, compacted quicklime, cement fluid waterproof material, cement mortar waterproof material and bentonite powder were found to have 100% of fish mortality, respectively, and membrane waterproof material showed 83.3% of mortality, indicating strong fish toxicity. Improved asphalt sheet (63.3%) and synthetic rubber sheet (53.3%) were analyzed to have medium fish toxicity, while bentonite sheet (6.7%), Hwang-toh (6.7%) and clay (3.3%) showed relatively lower mortality and fish toxicity. 3. Regarding the analysis on waterproofness in terms of the coefficient of permeability of each waterproof material, improved asphalt sheet, synthetic rubber sheet, membrane waterproof material, cement fluid and mortar waterproof material and bentonite sheet were found impervious in case no leakage takes place in construction. Bentonite powder was found practically impervious based on the analytical results from the experiment done in compliance with weight ratios. So were the clay and Hwang-toh from the experimental results. To sum up such results as found in the experiment mentioned so far, the values of harmfulness and waterproofness analyzed were different in each lab tank, but there was absolutely little correlation with the mortality gained from the experiment on fish toxicity. In the experiment of fish toxicity, environment-friendly waterproof materials were analyzed, and it was found that clay, Hwang-toh and bentonite sheet are highly environment-friendly. In contrast, synthetic rubber and improved asphalt sheets were found to have medium-level environment-friendliness. Also, membrane water-proof materials, compacted quicklime, cement fluid and mortar waterproof material and bentonite powder were analyzed to have low environment-friendliness.

• 대한치과보철학회지
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• 제41권2호
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• pp.111-127
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• 2003

Statement of problem : Resin cements were used widely on all ceramic crowns, but the influence of resin cements on biocells was not understood clearly. Purpose : This study was investigated to evaluate the biocompatibility of resin cements for all-ceramic crowns. Material and Method : The resin cements used in this study were Panavia F (Kuraray Co., Ltd. Japan), Variolink II (Vivadent Ets., Schann / Liechtenstein), and Bistite II (Bistite dual cure resin cement-clear Tokuyama Soda Co. Japan). The viability of normal human oral keratocytes, gingival fibroblast, and gingival fibroblast immortalized by Human Papilloma virus 16 was measured in vitro for evaluation of cytotoxicity on resin cements, and the response of pulp tissue was analyzed and evaluated with light microscope after application of cements at cutting edge of incisors. Results : The normal human oral keratocytes was the most sensitive to toxicity of resin cement, and toxicity of cements was higher in Bistite II than in Variolink II. The cell viability of immortalized gingival fibroblast did not affected by type of cement and cultivation period, but there was a tendency that cytotoxicity in Bistite II was higher than in Variolink II. The cell viability of gingival fibroblast was similar to that of immortalized gingival fibroblast regardless of cement type, but Bistite II showed more toxic than others after 5 days cultivation. The responses of pulp tissue according to cement type were similar after 2 days cultivation, but revealed high toxicity in Bistite II after 10 days cultivation. Conclusion : Variolink II was more biocompatible than any other resin cements used in this study.

• 환경위생공학
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• 제17권3호
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• pp.21-30
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• 2002

This study was Performed to evaluate the effective solidification of Cd sludge using cement and power plant fly ash as cement admixture, to identify the leaching characteristics of the heavy metal Cd sludge solidified, and to develope proper KLT(Korean Leaching Test) of hazardous waste. KLT was compared with EPT(Extraction Procedure Toxicity) and TCLP(Toxicity Characteristics Leaching Procedure). Fly ash contents ranged from 0% to 30% of cement weight. The experimental results showed that the optimum amount of fly ash replaced was 10% to 15% and KLT was less appropriate than EPA and TCLP. Also the purpose of the study was to suggest the modification factors on the leaching test currently used, based on the above mentioned aspects. The effects of pH, leaching time, leaching for agitating intensity, and leaching solvent were investigated. As the result of test, the leaching potential was relatively high when the pH and agitation intensity of leaching solution were 5 and 150rpm, respectively. Leaching time of six hours was found to be sufficient and the use of acetic acid as a leaching solvent is more useful in landfill site particularly.

• 대한골관절종양학회지
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• 제7권1호
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• pp.1-12
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• 2001

목적 : 아드리아마이신 함유 골시멘트의 국소 항암제 치료로서의 가능성을 알아보고자 실험을 실시하였다. 대상 및 방법 : Palcos R, LVC, CMW 3, Simplex P의 4종류 골시멘트에 아드리아마이신 2.5mg, 5mg, 25mg의 각각 다른 농도로 균일하게 섞은 후, 원주형 또는 납작한 형의 모양에 따른 아드리아마이신 용출 차이, ddH2O, 0.45% 식염수, 0.9% 식염수, 3% 식염수 등의 주위 환경에 따른 아드리아마이신 용출 차이를 연구하였다. 또한 용출된 아드리아마이신의 세포 독성을 알아보고자, 골육종 세포주 Saos-2를 골시멘트 단독, 각기 다른 3종류의 아드리아마이신 농도를 함유한 골시멘트와 같이 37 C, 5% $CO_2$ 조건하에서 가습 배양기내에서 배양을 실시하여, MTT assay 방법으로 세포 생존율을 확인하였다. 결과 : 납작한 모양이 원주형보다 아드리아마이신 용출이 많았고, 3%, 0.9%, 0.45%의 식염수 순으로 아드리아마이신 용출이 줄어 들었으며, CMW 3, Simplex P가 Palacos R, LVC보다 아드리아마이신 용출이 많았으며, 아드리아마이신 농도가 2.5mg, 5mg, 25mg 순으로 세포 독성은 각각 95%, 98%, 99%이었다. 결론 : 적절한 용량의 아드리아마이신을 골시멘트에 섞는다면, 용출된 아드리아마이신이 세포 독성을 가져 국소 항암제 치료 수단으로 이용 가능성을 확인하였다.

• Restorative Dentistry and Endodontics
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• 제34권5호
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• pp.415-423
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• 2009

$\beta$-glycerophosphate는 치수의 상아모세포 분화를 촉진하는 물질이다. Portland cement는 수중에서 장기간에 걸쳐 용해되기 때문에 $\beta$-glycerophosphate을 혼합한 Portland cement는 수산화칼슘과 함께 $\beta$-glycerophosphate를 장기간 용출하게 된다. 본 실험에서는 $\beta$-glycerophosphate을 혼합한 Portland cament에 대한 인간치수세포의 반응을 알아보았다. 인간 치수 세포에 대한 $\beta$-glycerophosphate의 효과를 알아보기 위해 다양한 농도의 $\beta$-glycerophosphate와 dexamethasone에 대한 인간 치수 세포의 ALP activity을 측정하였고 alizarin red S로 염색하여 관찰하였다. $\beta$-glycerophosphate가 다양한 농도(10 mM, 100 mM, 1 M)로 혼합된 Portland cement에 대한 인간 치수 세포의 MTS assay, ALP activity를 측정하고 SEM으로 관찰하였다. 치수세포의 석회화 정도를 관찰한 연구에서 $\beta$-glycerophosphate와 dexamethasone 단독으로 적용하였을 때 거의 효과가 없었으나 5 mM $\beta$-glycerophosphate와 100 nM dexamethasone을 혼합 적용하였을 때 가장 높은 ALP acticity를 보였다. 분화제를 첨가하거나 첨가하지 않은 모든 실험군에서 치수세포에 대한 독성은 관찰되지 않았으며 Portland cement에 10 mM $\beta$-glycerophosphate을 혼합한 시편의 ALP activity가 대조군에 비교하여 가장 많이 증가하였다. 결론적으로 $\beta$-glycerophosphate이 혼합된 Portland cement는 세포 독성이 없으며 첨가물이 없는 Portland cement에 비해 치수 분화 및 석회화를 더 많이 일으키므로 임상적으로 $\beta$-glycerophosphate을 혼합한 Portland cement 적용은 재료 하방에 더 많은 상아질을 형성시킬 것으로 추측된다.

• Restorative Dentistry and Endodontics
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• 제15권2호
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• pp.1-16
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• 1990

This study was to evaluate the cytotoxic effect in vitro and the tissue response within the rat peritoneal cavity to high copper amalgam and glass ionomer-silver cement, suggested for use as a retrograde endodontic filling material. In the cytotoxicity experiment, the radioactively ($^{51}Cr$) labeled L929 mouse fibroblasts were employed to determine the relative cytotoxicity of two experimental materials. Those materials were evaluated immediately after set and after one and seven days setting. In the tissue response experiment, two experimental materials were to evaluate mean peritoneal cellular count, differential cell count and the content of silver and copper in pooled packed cells and eluate samples taken by peritoneal lavage technique, and compared with surgical control after one day. two, four and six weeks of implantation. The results were as following: 1. High copper amalgam exhibited significant cytotoxicity immediately after set but showed no sign of toxicity after one day and seven days setting materials. 2. Glass ionomer-silver cement showed no sign of toxicity immediately after set and after one day and seven days setting. 3. High copper amalgam and glass ionomer-silver cement groups produce no significant difference in the mean peritoneal cell count when compared with the surgical control group after one day, two and four weeks of implantation. Surgical control group exhibited significantly a greater cell count when compared with the High copper amalgam group after six weeks. 4. High copper amalgam group increased significantly in the percentage macrophages after four and six weeks of implantation when compared with surgical control group. 5. The trace metal analysis involved an increased silver content in the elutes and an increased copper content in the packed cells of high copper amalgam group, and an increased silver content in the packed cells and elutes of glass ionomer-silver cement group.

• 한국건설순환자원학회지
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• 제7권3호
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• pp.24-26
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• 2012

• International Journal of Industrial Entomology and Biomaterials
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• 제26권1호
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• pp.41-46
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• 2013

The cladoceran Daphniamagna has been used as an aquatic test species in aquatic toxicology. To evaluate the aquatic toxicity of leachate from concrete, the immobilization of D. magna was observed after treatment of various concentrations of leachate specimens. Reliabilities of the culture condition and the experimental protocol for acute toxicity test were successfully achieved from the standard toxicity test. The leachates were prepared from the mixture of Ordinary Portland Cement (OPC) and pozzolanic admixtures, Pulverised fuel ash (PFA), Ground granulated blast furnace slag (GGBS) and GGBS containing loess. Acute toxicity test showed 100% immobilization of D. magna for OPC or PFA. The leachates from OPC or PFA had high pH 10 to 12. However, GGBS and GGBS containing loess showed less toxicity according to the concentrations. Especially, immobilization was not observed at the concentrations below 12.5% of GGBS containing loess. Also the range of pH for these specimens was 8 to 9. This suggested that the use of loess as the admixture in concrete may be useful to reduce eco-toxicity of leachates from concrete. This our study provided the harmfulness of the alkali leaching from concrete in aquatic environment and the usefulness of D. magna to evaluate the toxicity of leachates from concrete.