일반 칫솔과 씹는 칫솔의 치면세균막 제거 효과 융합연구

김송이,송은영,이유나,정용미,황의선,강경희 한국디지털정책학회 2018 디지털융복합연구 Vol.16 No.12

This study aimed to compare the elimination effect of dental plaque between general toothbrushes and chewing toothbrushes, so as to investigate whether the chewing toothbrushes have the practicality as the alternatives of general toothbrushes and their utilities in the real life. The study subjects were 30 healthy adults in their 20s who maintained the good dental condition over 16 teeth without systemic diseases, and the decline rates of dental plaque index after usages of general and chewing toothbrushes were calculated. Upon the comparisons of dental plaque decline rates before and after the usages of general and chewing toothbrushes, PHI index was declined from 7.02 to 1.91 in case of the general toothbrush demonstrating dental plaque decline by 72.79%, while it was declined from 6.72 to 4.08 in the chewing toothbrush demonstrating decline by 39.29%. Currently, a variety of dental care items are available in the Korean market, hence, various studies are required on the dental care items so as for the people to properly choose the items. 본 연구에서는 일반 칫솔과 씹는 칫솔의 치면세균막 제거효과를 비교하고 이를 통해 현재 출시된 씹는 칫솔이 일반 칫솔의 대용품으로 사용할만한 실용성을 갖추고 있는지와 실생활에서의 활용도 여부 등을 알아보고자 하였다. 연구 대상자는 전신 질환이 없으며 잔존치아 16개 이상 존재하는 구강상태가 양호한 20대의 건강한 성인 30명을 대상으로 하였으며, 일반칫솔과 씹는 칫솔 사용 후 치면세균막지수 감소율을 계산하였다. 일반 칫솔과 씹는 칫솔의 사용 전·후 치면세균막 감소 효과를 비교한 결과, 일반 칫솔의 경우 PHP index는 7.02에서 1.91로 감소하여 치면세균막이 72.79% 감소한 결과를 나타내었으며, 씹는 칫솔은 6.72에서 4.08로 감소하여 치면세균막이 39.29% 감소한 결과를 나타내었다. 현재 국내에서는 다양한 구강관리용품이 출시되어 판매되고 있으며 일반인들의 올바른 구강관리용품 선택을 위하여 구강관리용품에 대한 다양한 연구가 필요할 것으로 생각된다.

염소소독에 의한 하수처리장 방류수의 소독부산물 발생에 관한 연구

김증운(Jeung-Woon Kim),송현실(Hyun-SiI Song),배병욱(Byung-Uk Bae) 대전대학교 환경문제연구소 2004 환경문제연구소 논문집 Vol.8 No.-

본 연구에서는 대전광역시 하수종말처리장 4단계 방류수를 대상으로 염소소독 실험을 수행하고 염소 주입농도에 따른 대장균군 및 일반세균의 살균효율과 소독부산물의 생성정도를 조사하였다. 2003년 2월부터 10월까지의 대상하수처리장 4단계 방류수의 대장균군수는 1,100~2,800 개/㎖, 균은 3,500~21,600 개/㎖ 이었으며, 기타 항목별 평균농도는 BOD₅ 10.2, COD_Mn 13.5, SS 7.4 리고 T-N 과 T-P 가 각각 16.243, 0.994 mg/ℓ 이었다. 또한 하수처리장 방류수의 SUVA(specifi absorbance) 값은 2.27 로 친수성, 비방향족, 그리고 저분자량의 물질들로 구성되어 있어 생분해 성이 클 것으로 판단된다. 염소소독 실험결과 pH 7.0, 수온 20±0.5℃ 상태에서 99%이상의 소독을 얻기 위해서는 대장균군의 경우 염소주입농도 1.0 mg/ℓ 에서 10분, 일반세균의 경우 1.0 mg/ℓ 30 분, 2.0 mg/ℓ 에서는 20분, 그리고 3.0mg/ℓ 및 5.0 mg/ℓ 에서는 각각 10분의 접촉시간이 필요한 로 나타났다. 미국의 하수처리장 방류수 대장균군 기준은 1,000 MPN/1OO㎖ 로 염소주입농도 1.0 에서 10분간 접촉시킬 때 이 기준을 만족할 수 있었으며, 이 조건에서 trihalomethanes haloacetonitriles는 검출되지 않았다. pH 7.0, 수온 20±0.5℃, 염소주입농도 20 mg/ℓ, 접촉시 에서 trihalomethanes, haloacetonitriles, 그리고 haloacetic acids의 생성농도는 각각 29.86 그리고 3.1107μg/ℓ 이었으며, chloroform은 22.3467μg/ℓ으로 전체 trihalomethanes의 75.0 내었다. 파과점 염소주입 실험결과, 초기 암모니아성 질소의 농도 1.646 mg/ℓ 의 약 9.1 배까지 염소 입량을 증가시켰을 때 파과점에 도달하였다. 소독부산물의 생성정도는 암모니아성 질소 농도에 반비례하였는데, 암모니아성 질소와 각 소독부산물과의 상관관계(R²)는 trihalomethanes이 O. haloacetonitriles이 0.8169, 그리고 haloacetic acids는 0.7206 이었다. 일반적으로 하수처리는 유기물과 세균이 많기 때문에 높은 농도의 염소소독이 필요할 것이라고 생각되어지나, 본 연구의 결과 수온 및 초기 pH의 영향에 크게 상관없이 소량의 염소주입만으로도 충분한 소독효과를 기대할 수 있었다. 아울러 방류수역의 희석율을 고려하면, 염소소독 후 발생되는 소독부산물은 자체의 휘발과 희석작용에 의해 그 양이 현저히 감소됨으로써 소독부산물이 상수원으로 유입되는 문제는 크지 않을 것으로 판단된다. In Korea, the disinfection of discharged wastewater has become mandatory in 20 municipal wastewater treatment plant (WWTP) have to satisfy the discharge limits. investigate the disinfection efficiency of chlorine and the effect of chlorination on the DBPs (disinfection by-products) in the discharged wastewater. chlorine disinfection conducted. For these purpose, the Daejeon municipal WWTP was selected as a targ water samples were taken from the final sedimentation basin. Based on the experiment the optimum disinfection strategy was proposed, which would satisfy the newly disinfection limits. Typical concentrations of index microorganisms in the discharged wastewater was in the range of 1,100 ~ 2,800 CFU/㎖ for total coliforms and 3,500 ~ 21,600 CFU/㎖ for heterotrophic bacteria. Analysis of other water quality parameters showed that discharged wastewater contained 10.2 mg/ℓ of BOD₅, 13.5 mg/ℓ of COD_Mn, 7.4 mg/ℓ of SS, 16.243 mg/ℓ of T-N, and 0.994 mg/ℓ of T-P The SUVA (specific UV absorbance) value of discharged wastewater was 2.27. This result indicates that the organic component of discharged wastewater is mainly consisted of non-humic substances, which are characterized by hydrophilic, non-aromatic, and low-molecular weights. In the case of total coliforms, the survival rate was 8.9% when 0.5 mg/ℓ of chlorine was contacted for 30 min at pH 7.0, 20±0.5℃. In order to get more than 99% of disinfection efficiency, it was proved that more than 10 min of contact time was required when chlorine dose was 1.0 mg/ℓ. In the case of heterotrophic bacteria, in order to achieve more than 99 % of disinfection efficiency at pH 7.0, 20±0.5℃, the required contact time was 30 min at chlorine dose of 1.0 mg/ℓ, 20 min at 2.0 mg/ℓ, and 10 min at 3.0 mg/ℓ and 5.0, respectively When the discharged wastewater was disinfected with 1.0 mg/ℓ chlorine for 10 min, it was possible to satisfy the U.S. EPA's total coliforms standard (1,000MPN/100㎖). The residual chlorine concentration was 0.42 mg/ℓ in this experimental condition, but both THMs and HANs were not detected probably due to the formation of combined chlorine. When the discharged wastewater was disinfected with 20 mg/ℓ of chlorine for 180 min at pH 7.0, 20±0.5℃, the concentrations of THMs, HANs, and HAAs was 29.8, 2.9, and 3.1 μg/ℓ, respectively. The concentration of chloroform was 22.3467 μg/ℓ, corresponding to 75 % of the total THMs. When the NH₃-N concentration of discharged wastewater was 1.646 mg/ℓ, about 9.1 times of chlorine dosage was required to obtain breakpoint chlorination. It was found that the formation of DBPs was inversely proportional to the concentration of NH₃-N present in wastewater. The correlation coefficient (R²) between NH₃-N and three kinds of DBPs was 0.9647 for THMs, 0.9038 for HANs, and 0.8489 for HAAs, respectively.

재래식 화장실 주변의 수질오염에 대한 연구

崔茂雄 한국지하수학회 1995 지하수 Vol.4-5 No.-

재래식 화장실 주변의 수질오염정도를 조사하기 위해 경기도 여주군 점동면일대에서 16개 지점의 우물을 대상으로 3회에 걸쳐 대장균과 일반세균을 중심으로 수질을 조사하였다. 그 결과 대장균은 거의 모든 지점에서 검출되었지만 일반세균은 조사지점마다 차이가 나타나 평균 36%가 음용수기준에 합격되었다. 계절적으로 보면 검출된 대장균이나 일반세균의 수는 조사시기에 따라 변화가 있어 94년 5월에 가장 그 수가 많이 나타나고 있다. (주요단어: 재래식 화장실, 대장균, 일반세균, 수질오염)

다중이용시설의 실내공기 미생물 오염실태에 관한 연구

박경수,최상곤,홍진관 대한설비공학회 2006 설비공학 논문집 Vol.18 No.8

Recently, indoor air quality(IAQ) is one of the greatest problems in our modern societies. Although research for IAQ is made rapid progress but IAQ problems concerning indoor microorganism contamination is required to be studied still more. So we have investigated the indoor microorganism concentration of a variety of department store, subway station, underground shopping center, kindergartens, library where people complain about the indoor air quality. The experiment on microorganism concentration of indoor air was carried out and the average of total microorganisms was measured. Comparing the experimental results with existing foreign criterion, the experimental results show that the ministry of environment recommendation microorganism concentration value(800CFU/m3) is in need of revision in the near future.

견과종실류의 위해 미생물 오염도 조사

홍승희(Seung?Hee Hong) 한국엔터테인먼트산업학회 2016 한국엔터테인먼트산업학회논문지 Vol.10 No.6

견과종실류의 미생물 오염도를 분석하기 위하여 호두, 땅콩, 아몬드 및 호박씨의 일반세균수 및 식중독 원인균을 조사하였다. 각 시료에서 일반세균수는 호두에서는 평균 1.3 log CFU/g, 땅콩은 1.4 log CFU/g, 아몬드는 0.3 log CFU/g, 그리고 호박씨는 2.9 log CFU/g를 보였다. 호박씨는 모든 구입 장소에서 높은 오염을 보였으며, 특히 D마트의 경우는 4.0 log CFU/g로 매우 높은 오염을 나타냈다. 견과종실류의 식중독균 오염을 분석하기 위하여 E.coli O157, S. aureus, B. cereus, V. parahaemolyticus, L. monocytogenes, Y.enterocolitica, Salmonella spp. Shigella spp. 식중독균의 PCR을 수행한 결과, 호두 3곳, 땅콩 2곳, 아몬드 1곳, 호박씨 3곳에서 모두 B. cereus가 검출되었다. B. cereus의 오염 정도를 정량분석한 결과, 땅콩 3곳과 호박씨 3곳에서 B. cereus가 검출되었다. 가장 높은 오염을 보인 곳은 C마트의 호박씨 2.8 log CFU/g과 A마트의 호박씨 2.6 log CFU/g로 나타났다. 그러므로 견과종실유는 가열하지 않고 섭취하는 식품으로써 식중독을 예방하기 위하여 가공 및 유통단계에서 위생을 철저하게 관리할 필요하다고 사료된다. This study was carried out to analysis microbial contamination of walnut, peanut, almond, and pumpkin seed on sale in several market. We examined total aerobic bacteria and various foodborne illness bacteria from nuts and seeds. Total aerobic bacteria of each sample was showed in mean 1.3 log CFU/g for walnut, mean 1.4 log CFU/g for peanut, mean 0.3 log CFU/g for almond, and mean 2.9 log CFU/g for pumpkin seed. Specially, pumpkin seed appeared high total aerobic bacteria contamination among nuts and seeds and contamination level reached 4.0 log CFU/g in D market. For assessment of foodborne illness bacteria contamination, we conducted PCR with mulplex primers of E.coli O157, S. aureus, B. cereus, V. parahaemolyticus, L. monocytogenes, Y.enterocolitica, Salmonella spp. Shigella spp. B. cereus was amplified walnut in 3 market, peanut in 2 market, almond in 1 market, and pumpkin seed in 3 market. The result of quantitative analysis of B. cereus contamination revealed 3 contamination market for peanut and pumpkin seed and showed higher contamination rate of 2.8 log CFU/g in C mark, 2.6 log CFU/g in A market of pumpkin seed. Therefore, strict food safety control in processing and circulation of nuts and seeds will be need for prevent foodborne disease and improve human health.

UV/TiO_(2) 수처리 공정에서의 살균에 관한 연구

이규환,이상진,이용재,이동석 강원대학교 산업기술연구소 2007 産業技術硏究 Vol.27 No.A

This study investigated disinfection effect by general water purifier and water purifier with UV light disinfection. The results are as follows : (ⅰ) The general bacteria existed plentifully in a storage tank before treatment (ⅱ) Water treated in water purifier did not meet the water treatment regulation standard since the presence of bacteria, whereas with UV light application the regulation standard is totally satisfied. (ⅲ) Photocatalytic disinfection process with UV light in the presence of TiO_(2) more effectively killed general bacteria than UV light only.

실내오염 저감을 위한 공동주택 환기시스템의 개선방안에 대한 연구

황태철(Tae Chul Hwang),이현우(Hyun Woo Lee),최상곤(Sang Gon Choi),홍진관(Jin Kwan Hong) 대한설비공학회 2008 설비공학 논문집 Vol.20 No.6

Recently, Indoor air quality (IAQ) is one of the most important problem in our daily life of modern societies. Mechanical ventilation system is being recommended as an effective method to improve IAQ in apartment houses. And then, in Korea, building industry should install ventilation system in apartment house by the building construction code. In this study, to improve IAQ caused by microbial and chemical contaminant such as bacteria and TVQC, three types of mechanical ventilation system of apartment house including HRV were simulated by multizone modeling. Simulation results suggest an appropriate and economical renovation method of apartment house ventilation system for reducing indoor air contamination.

대학교의 PC실과 대학교 주변 PC방의 키보드 · 마우스의 오염도 비교와 사용자의 인식조사

윤지혜,박혜린,윤재은,조경순,조아라,조혜림,최고은 환경독성보건학회 2013 한국독성학회 심포지움 및 학술발표회 Vol.2013 No.10

DOF (Dissolved Ozone Flotation)를 이용한 부유물질과 총인의 제거와 소득의 동시효과에 관한 연구

이병호,김성혁,이상배,김미정 대한상하수도학회 2004 상하수도학회지 Vol.18 No.2

Effluent of wastewater treatment plant is to be disinfected to protect drinking water sources. DOF (Dissolved Ozone Flotation) was developed to meet this purpose. DOF was developed by combining DAF system with ozone. DAF system has good floating power with numerous microbubbles, and ozone has strong oxidation capability. And DOF system has good floating power and strong oxidation capability simultaneously. When DOF was applied to secondary wastewater effluent, color of 11CU in raw water which was secondary effluent was reduced to 1CU by the DOF system. Removal rate of other water quality parameters treated by DOF were also higher than that by DAF, which were proved the strength of oxidation capability of ozone. When ozone concentration of 3.3㎎/l were applied in DOF system, general aerobic bacteria were reduced to 5CFU/㎖ from TNTC (Too many Numbers To Count). With the same ozone concentration, total coliform were not detected at all. These figures are under the numbers of drinking water regulation. These microbes were the target parameters of DOF. It was proved that DOF was very effective in disinfection of wastewater treatment plant effluent as well as in removal of color, turbidity, and T-P.

오존/페록시 라디칼 처리시스템을 이용한 수중 오염물 처리

정종태(Jong-Tae Jung),김종오(Jong-Oh Kim),이진우(Jin-Woo Lee),권범근(Bum-Gun Kwon) 한국지반환경공학회 2007 한국지반환경공학회 학술발표회논문집 Vol.2007 No.-