• 제목/요약/키워드: heat sterilization

검색결과 112건 처리시간 0.029초

열멸균과정이 nickel titanium호선의 기계적 성질과 표면상태에 미치는 영향 (The Effect of Heat Sterilization on the Surface Topography and the Tensile Properties in Various Nickel Titanium Wires Including a Korean Product)

  • 김병호;남동석;양원식
    • 대한치과교정학회지
    • /
    • 제28권6호
    • /
    • pp.927-935
    • /
    • 1998
  • 본 연구의 목적은 수종의 nickel titanium 호선을 열멸균 처리 하였을 때 나타나는 물리적성질과 표면상태의 변화를 정량적으로 평가하고자 하는 것이다. 연구에 사용된 재료는 국산제품을 포함한 4종의 .$016\times.22$ 각형 nickel-titanium호선이며, 이들을 건열소독($180^{\circ}C$, 60분)군과 가압증기멸균($121^{\circ}C$, 15-20 psi, 30분)군, 그리고 아무런 처리를 하지 않은 대조군으로 구분하였다. 인정특성은 Inston (Model 4466, load cell capacity:1000kg)을 이용하여 표점거리 40mm, cross head는 분당 5mm의 속도, 실온의 조건에서 평가하였으며 쳐대인장강도와 연신율, 그리고 탄성률을 측정 및 계산하였다. 표면상태는 주사전자현미경과 profilometer로써 평가하였고, 1-test를 이용하여 통계적 분석을 하였다. 결과는 다음과 같다. 1. 실험에 사용된 nickel-titanium호선들은 모두 두가지 열멸균 처리에 의해 인장특성에 있어서 유의할 만한 변화를 보이지 않았다/ 2. 대조군에서 NiTi가 가장 높은 펴ㅛ면거칠기를 보였고, Align과 Sentalloy는 동일한 정도의 값을, Optimalloy는 가장 낮은 값을 지니고 있었다. 3. Align과 Optimalloy는 두가지 열멸균처리 후에 모두 유의할 만한 표면상태의 변화를 보이지 않았다. 그러나 NiTi는 건열소독후에 표면거칠기의 증가를 보였으며 Sentalloy는 두가지 열멸균후에 표면상태의 변화와 표면거칠기의 유위한 증가를 보였다.

  • PDF

당근 가공시 열처리 조건에 따른 휘발성 Terpenoids 함량 비교 (Comparison of Volatile Terpenoid Content from Thermal Processing Condition in Carrot)

  • 박신
    • 생명과학회지
    • /
    • 제12권5호
    • /
    • pp.589-594
    • /
    • 2002
  • 당근의 열처리 조건에 따른 휘발성 terpenoids 함량의 변화를 조사하였는데, 열처리 온도가 높을수록 휘발성 terpenoids가 많이 감소하였으며, 열처리 시간에 따른 휘발성 terpenoids는 $\alpha$-pinene 및 total terpenoids의 경우 최초 30분 동안 급속히 감속하였으며, 그 후 시간이 지남에 따라 감소율이 낮아지는 경향을 보였다 당근주스의 살균 온도별, 시간별 휘발성 terpenoids의 변화를 조사한 결과, 살균온도가 높을수록 휘발성 terpenoids 함량이 빠른 속도로 감소함을 보여주고 있으며, 살균시간에 따른 휘발성 terpenoids의 함량은 최초 20분간 급속히 감소하다가 이후에는 완만하게 감소하였다. Total terpenoids의 경우 10$0^{\circ}C$에서 20분간 살균했을 시 6$0^{\circ}C$ 및 8$0^{\circ}C$에서 60분간 살균했을 시 보다 더 많이 감소하였는데, 당근주스의 휘발성terpenoids 함량을 줄이기 위해서는 고온단시간 살균이 저온장시간 살균보다 더 유리하다는 것을 알 수 있었다.

Influence of autoclave sterilization procedures on the cyclic fatigue resistance of heat-treated nickel-titanium instruments: a systematic review

  • Silva, Emmanuel Joao Nogueira Leal;Zanon, Mayara;Hecksher, Fernanda;Belladonna, Felipe Goncalves;de Vasconcelos, Rafaela Andrade;da Silva Fidalgo, Tatiana Kelly
    • Restorative Dentistry and Endodontics
    • /
    • 제45권2호
    • /
    • pp.25.1-25.12
    • /
    • 2020
  • Objectives: This systematic review evaluated the influence of autoclave sterilization procedures on the cyclic fatigue resistance of heat-treated nickel-titanium (NiTi) instruments. Materials and Methods: A systematic search without restrictions was conducted in the following electronic databases: PubMed, Scopus, Web of Science, ScienceDirect, Cochrane, and Open Grey. The hand search was also performed in the main endodontic journals. The eligible studies were submitted to the methodological assessment and data extraction. Results: From 203 abstracts, a total of 10 articles matched the eligible criteria. After reading the full articles, 2 were excluded because of the absence of the heat-treated instruments in the experimental design and 3 due to the lack of a control group using heat-treated instruments without autoclave sterilization. From the 5 included studies, 1 presented a low risk of bias, 3 presented moderate and 1 high risk. It was observed heterogeneous findings in the included studies, with autoclave sterilization cycles increasing, decreasing or not affecting the cyclic fatigue life of heat-treated NiTi instruments. However, the retrieved studies evaluating the cyclic fatigue resistance of endodontic instruments presented different protocols and assessing outcomes, this variability makes the findings less comparable within and also between groups and preclude the establishment of an unbiased scientific evidence base. Conclusions: Considering the little scientific evidence and considerable risk of bias, it is still possible to conclude that autoclave sterilization procedures appear to influence the cyclic fatigue resistance of heat-treated NiTi instruments.

저알코올 와인의 가열 및 비가열 살균 후 품질 특성 및 기능성 (Quality Characteristics and Functionality of Low Alcohol Wines after Heat Sterilization and Non-Thermal Sterilization)

  • 신혜림;박혜진;황온빛;최성열;박의광;윤동규;윤향식
    • 한국식품영양학회지
    • /
    • 제35권5호
    • /
    • pp.343-352
    • /
    • 2022
  • Low alcohol (6%) wines were manufactured using Campbell Early. To develop the sterilization process of low alcohol wines, red wines were heat sterilized, and rose wines were nonthermal sterilized by concentration using potassium metasulfite and potassium sorbate. Samples were stored at 25℃ and quality characteristics were investigated by period. Results of this study revealed the pH of the samples after sterilization ranged from 3.15 to 3.19, and the total acidity of wines ranged from 0.011 to 0.024%. The free SO2 contents of wines ranged from 13.00 to 29.678 mg/L, and the total SO2 contents of wines ranged from 47.50 to 121.00 mg/L. L (lightness) of wines decreased whereas a (redness) and b(yellowness) increased. The hue value of wines ranged from 0.52 to 1.03, and decreased significantly(not including rose sweet wines). The color intensity of red and rose dry wines after sterilization increased, whereas red and rose sweet wines decreased. The DPPH radical scavenging activity of red wines and rose wines ranged between 75.50 to 89.23%, and 36.60 to 56.54%, respectively. The total polyphenol contents were 57.51~182.63 mg%. Results of this study provide scientific information to establish the sterilization process of low alcohol wines.

Sterilization effect and fatty acid composition of silkworm powder (Bombyx mori L.) by heat treatment

  • Jo, You-Young;Kim, Su-Bae;Eom, Tae Dong;Park, Seong-Won;Kim, Seong-Ryul;Kim, Seong-Wan;Ji, Sang Duk;Kim, Kee Young;Kweon, HaeYong
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제39권1호
    • /
    • pp.39-44
    • /
    • 2019
  • The effect of heat treatment on the sterilization and fatty acid compositions of silkworm powder was carried out under the guidance of Ministry of Food and Drug Safety. Food borne pathogens or microorganisms including E. coli, Salmonella spp., Listeria monocytogenes, Staphylococus aureus, Clostridium perfringens and aflatoxin, were not detected. The fatty acid composition was hardly changed after the silkworm powder was treated to a high temperature of $121^{\circ}C$. The low temperature sterilization of silkworm powder at $63^{\circ}C$ decreased the concentration of E. coli while high temperature sterilization at $121^{\circ}C$ has found no traces of microorganism.

Redox 반응을 이용한 해수 살균에 대한 연구 (A Study on the Sterilization of Sea Water using Redox Reaction)

  • 송주영;김종화
    • 한국응용과학기술학회지
    • /
    • 제28권1호
    • /
    • pp.29-34
    • /
    • 2011
  • The sterilization of strain and algae in sea water was studied to see the possibility to apply the redox reaction of metal alloy to meet the international marine organization(IMO) regulation, which was to regulate deballasting concentration of strain and algae above 99% of sterilization. Two different kinds of brass were heat treated at different temperature and cooled rapidly to conserve the specific character of ${\beta}$ brass. Untreated Muntz metal showed the best result of antimicrobial rate in sea water, and 7:3 brass showed similar result to Muntz metal. Heavy metal elution rate was inversely proportional to the sterilization capability.

오존처리를 이용한 유자청의 비가열살균 (Non-Heat Sterilization of Yujacheong Using Ozone Treatment)

  • 이보배;윤창용;남승희
    • 한국식품영양학회지
    • /
    • 제36권4호
    • /
    • pp.334-339
    • /
    • 2023
  • To suppress mold generation of yujacheong, Penicillium chrysogenum LB31 was cultured, and spores were harvested and put into yujacheong. Antioxidant activity, useful ingredients, mold size and incidence were investigated while storing yujacheong for 30 days, after sterilization with different methods (nontreatment, ozone gas emission, heating after ozone gas emission and heating). The results showed that the content of narirutin, naringin, hesperidin, or neohesperidin, which are functional components of yuzu, increased as the storage period increased in all the treatment units. In addition, mold generation was not observed until the 15th day in the heat treatment group after ozone gas emission. As the treatment group emitted ozone gas. molds of 34.8 and 112 mm2 in size were observed on the 30th day. These results suggested that ozone sterilization can prevent microbial contamination, further extending the shelf life of yuzacheong and maintaining a fresh state.

레토르트 처리한 김치찌개 제품의 최적 살균조건 결정 (Determination of Optimum Sterilization Condition for the Production of Retorted Kimchi Soup)

  • 천희순;박은지;조원일;황금택;정명수;최준봉
    • 한국조리학회지
    • /
    • 제20권6호
    • /
    • pp.254-261
    • /
    • 2014
  • 레토르트 김치찌개의 최적 가열 살균 조건 설정을 위해 정치식 및 회전식 레토르트 방식을 이용하여 최적화 연구를 수행하였다. 연구 고찰 결과 가열 특성은 레토르트 살균 방식에 의해 영향을 많이 받아 회전식에서는 $120.7^{\circ}C$, 13분, 정치식에서는 $120.7^{\circ}C$, 20분의 가열 살균이 최적 공정 조건으로 나타났다. 두 가지 레토르트 방식에서 김치찌개 파우치 내 냉점의 $F_0$ 값은 동일한 결과를 보여 회전식이 정치식 보다 승온이 더 빠르며, 또한 빠른 온도 상승으로 시료 위치별 온도 편차도 적게 발생하였다. 이러한 전열 특성으로 냉점에서 동일 $F_0$ 값 도달에 있어 회전식 레토르트 방식이 정치식에 비해 가열 살균시간이 35~45%의 단축되는 큰 장점이 있어 전반맛, 향, 색상과 조직감이 유의차 (p<0.05) 있게 향상되었다. 이러한 장점으로 육, 해물, 야채 등의 고형물이 포함되어 있는 다양한 메뉴의 레토르트 파우치 식품의 관능품질이 크게 향상될 것으로 기대된다.

온실 내 토양소독을 위한 지중난방시스템의 지중 열전달 특성 (Underground Heat Transfer Characteristics of the Underground Heating System for Soil Sterilization in Greenhouse)

  • 박경규;하유신;홍동혁;장승호;김진현
    • Journal of Biosystems Engineering
    • /
    • 제35권2호
    • /
    • pp.108-115
    • /
    • 2010
  • This study was conducted to estimate the optimum temperature and required time for soil sterilization when heated water was circulated through underground heating pipes in the greenhouse which solar heat was influenced to the temperature of soil during the summer day. Two different types of heating pipes were used for the experiment. One was a polyethylene pipe(XL) and the other was a corrugated ring shaped stainless steel pipe(STS). The results of the studies were summarized as follows; By measuring the thermal characteristics of the XL and STS, it was examined that the average temperature differences of the inlet and outlet were $8.5^{\circ}C$ and $13.3^{\circ}C$, the average flowrates were 15.3 L/min and 5.6 L/min, and the average radiation powers were 9.1 kW and 4.1 kW, respectively. As results of the regression analysis of underground temperatures, when average soil temperature was$35^{\circ}C$, an average water temperature was $80^{\circ}C$, and XL was used, it was estimated that the possible heat transfer distance, the required time for heat transfer and heat flux to reach the underground temperature of $60^{\circ}C$ were 300 mm, 230 hours, and $7.57kW/m^2$, respectively.

방사선항균법과 개스항균법의 비교연구 (A Comparative Study of Radiation and Gas Sterilization.)

  • 정해원;유영수
    • 한국환경보건학회지
    • /
    • 제8권1호
    • /
    • pp.81-97
    • /
    • 1982
  • Ethylene oxide gas has been used as a cold sterilant for heat-sensitive medical equipments and as a fumigant for food for more than 30 years, and it is used more widely than radiation although radiation sterilization has made significant inroads in recent years. But according to recent studies of toxicities such as mutagenicity, haemolytic effect and possible carcinogenicity of Ethylene oxide (ETO) and its two main reaction products, Ethylene chlorohydrin (ETCH) and Ethylene glycol (ETG), Environmental Protection Agency in U.S.A. has suggested some regulations on residual gas in drug products and medical devices for human use. The mutagenic activity of ETO compared with that of X-ray has an equivalency of 1 ppm/hr for ETO as compared to 20 mrad for X-ray, and one could suggest the present maximum allowable concentration for ETO (50 ppm) should be 400 times lower than the radiation standard (2.5 mrad/hr). Although radiation sterilization has advantages of simplicity of operation and complete reliability, changes of physico-chemical properties with possible formation of toxic substances may occur. It is therefore necessary to make some regulations of our own for residual toxicities orginated from each sterilization method.

  • PDF