• 제목/요약/키워드: UV-rays

검색결과 147건 처리시간 0.024초

Strain Improvement of Candida tropicalis for the Production of Xylitol: Biochemical and Physiological Characterization of Wild-type and Mutant Strain CT-OMV5

  • Rao Ravella Sreenivas;Jyothi Cherukuri Pavanna;Prakasham Reddy Shetty;Rao Chaganti Subba;Sarma Ponnupalli Nageshwara;Rao Linga Venkateswar
    • Journal of Microbiology
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    • 제44권1호
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    • pp.113-120
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    • 2006
  • Candida tropicalis was treated with ultraviolet (UV) rays, and the mutants obtained were screened for xylitol production. One of the mutants, the UV1 produced 0.81g of xylitol per gram of xylose. This was further mutated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and the mutants obtained were screened for xylitol production. One of the mutants (CT-OMV5) produced 0.85g/g of xylitol from xylose. Xylitol production improved to 0.87 g/g of xylose with this strain when the production medium was supplemented with urea. The CT-OMV5 mutant strain differs by 12 tests when compared to the wild-type Candida tropicalis strain. The XR activity was higher in mutant CT-OMV5. The distinct difference between the mutant and wild-type strain is the presence of numerous chlamvdospores in the mutant. In this investigation, we have demonstrated that mutagenesis was successful in generating a superior xylitol-producing strain, CT-OMV5, and uncovered distinctive biochemical and physiological characteristics of the wild-type and mutant strain, CT-OMV5.

반응성 염료를 이용한 양모직물의 광그라프트 염색 (Photo-grafting Dyeing of Wool Fabrics with ${\alpha}$-bromoacrylamide reactive dye)

  • 동위엔위엔;장진호
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2011년도 제44차 학술발표회
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    • pp.31-31
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    • 2011
  • Lanasol dyes containing ${\alpha}$-bromoacrylamide or ${\alpha},{\beta}$-dibromopropionylamide group are used for wool dyeing. They are normally applied to wool under pH 4.5 to 6.5 at $100^{\circ}C$. Although wool fabric can be dyed to obtain deep colour, high light and wet fastness, the dyeing processes need long dyeing time at high temperature, with salt addition, which inevitably causes environmental problems. Grafting is a modification method for textile where monomers are covalently bonded onto the polymer chain. It can be initiated by ozone, ${\gamma}$ rays, electron beams, plasma, corona discharge and UV irradiation. Coloration by UV-induced photografting exhibits several advantages such as fast reaction rate, energy saving, simple equipment, easy exploitation and environmentally friendliness. Also it requires much lower energy compared to the conventional dyeing and less damage to the substrate. In this study, a direct sequential UV-induced photografting onto wool fabrics was discussed. To understand the graft polymerization mechanism further, several characterization methods were used. Moreover, the effects of several principal factors on the graft photopolymerization were investigated. Furthermore, the colorfastness results were compared with conventional dyeing methods.

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22.9[kV]급 애자의 표면오염에 의한 자외선 영상과 열화판정 (The UV Images and Aging Judgement with Behaviors Caused by Surface Contamination on 22.9[kV] Class Insulators)

  • 송길목;김영석
    • 조명전기설비학회논문지
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    • 제24권1호
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    • pp.167-174
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    • 2010
  • 본 연구에서는 22.9[kV] 애자의 표면오염에 의한 자외선 영상과 거동을 통해 자외선 이미지 형태 판단법을 정의하였다. 코로나 방전에 의해 나타나는 자외선 영상은 아메바, 젤리피쉬, 썬플라워 형태 등 3가지로 나누어지며, 세부적으로는 8개의 진행 메커니즘으로 구분하였다. 전력설비가 설치된 현장에서는 즉각적으로 이 판단 방법으로 전력 설비의 열화된 부분을 찾을 수 있다. 이는 신뢰성 있는 데이터를 통해 전력설비의 열화를 판단하는 기준에 활용이 가능하다. 향후 현장진단에 적합한 기술로서의 연구가 활용될 것이다.

아웃도어 라이프 활성화를 위안 페이스 커버 개발 연구 (The Development of Face Cover Designs to Activate Outdoor Life)

  • 김찬주;노미경
    • 복식
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    • 제59권1호
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    • pp.47-59
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    • 2009
  • This paper aimed at the development of face covers which is face protection articles for blocking UV rays and yellow sands, with a view to assist the further activation of outdoor life. The four-stage design process of field study, design, design evaluation, final selection of designs was set up for the effective product development. Field study included on-line and off-line market survey on the products for sale in market and observation on those wearing face covers. Depth interviews were done to know consumer understandings and satisfaction levels for current face covers. The results of market survey showed that most of the face covers currently in the market were mask types, which were produced for the blocking of dust and yellow sands rather than UV ray protection. The major clients of the mask were the women in their 30's-50's and the designs for these clients were very limited. Since the number of younger women and men enjoy the outdoor sports has increased, the face covers for these people should be developed. For this purpose, the direction of new face cover design had 2 points: diversification of design in terms of color, material, shape and giving seasonal differences. 12 designs were designed on the first design stage, but after both wearing test by 16 testees and UV ray blocking test to evaluate these designs, 6 face cover designs were finally selected.

A Study on the Development of Sensor-Based Smart Wappen System -Focus on UV Sensor and Gas Sensor-

  • Park, Jinhee;Kim, Jooyong
    • 패션비즈니스
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    • 제22권6호
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    • pp.94-104
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    • 2018
  • The objective of this study was to develop a wearable systems that protect users, based on sensors that are easy to use, from accidents caused by harmful gases in the operator's poor working environment or the risk of ultraviolet rays during outdoor activities. By developing smart wappen with Light Emitting Diode (LED) light alarm function including UV sensor and gas sensor and central processing unit, systems that are applied to daily wear and work clothes to explore the possibility of user-centered, harmful environment monitoring products in real time were proposed. Each sensor was applied to sportswear and work clothes and the wappen system consisted of lightweight and thin form as a whole. Wappen to cover the device had one sheet cover on the front and another cover from the inside to form a sandwich like formation. Wappen was made in the same form as regular clothes that doesn't damage the exterior then a removable wappen system was developed using Velcro and snap methods to enable the separation of device or the exchange of batteries. De-adhesion method can occur in two ways, from the outside and from the inside, so the design is selected depending on the application. This study shows the significance of the development of sensor-based smart clothing, in that it presented a universal model for users.

비무장지대 평화생명벨트 인접해안에서의 레저관광활동 가이드라인을 위한 자외선 반사량 원격측정 (Remote Measurement of Ultraviolet Reflections for the Guidelines for Leisure Tourism Activities on the Adjacent Coast of the Demilitarized Zone Peace Life Belt)

  • 어재선;최철재
    • 한국전자통신학회논문지
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    • 제17권3호
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    • pp.499-506
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    • 2022
  • 2021년 동해북부선 착공으로 비무장지대(Demilitarized Zone:DMZ)의 평화적 활용의 기대치가 높아지고있다. 이에 따라 비무장지대를 안보생태관광으로 활용한 인근 해변에서의 레저관광 활동에 대비해야 한다. 그러나 오존층의 파괴로 인한 지표면 자외선(Ultravilolet:UV) 양의 증가에도 불구하고 아직까지 자외선 노출 위험가이드라인이 없다. 본 논문에서는 원격탐사를 이용한 비무장지대 인접 해안에서의 자외선 반사량 측정하고 분석하였다. 제시된 결과가 인근지역 레저관광 활동에서의 자외선 가이드라인 마련에 기초자료로 활용되기를 기대한다.

투명 전도성 ZITO/Ag/ZITO 다층막 필름 적용을 위한 아크릴레이트 기반 고분자분산액정의 전기광학적 특성 최적화 (Optimization of Electro-Optical Properties of Acrylate-based Polymer-Dispersed Liquid Crystals for use in Transparent Conductive ZITO/Ag/ZITO Multilayer Films)

  • 조정대;김양배;허기석;김은미;홍진후
    • 공업화학
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    • 제31권3호
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    • pp.291-298
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    • 2020
  • 본 연구에서는 RF/DC 마그네트론 증착법을 이용하여 실온에서 유리 기판 상에 ZITO/Ag/ZITO 다층막 투명전극을 제조하였다. ZITO/Ag/ZITO (100/8/42 nm)로 이루어진 다층막 구조에 대해, 면저항이 9.4 Ω/㎡이고 550 nm에서 투과도가 83.2%인 투명 전도성 필름이 얻어졌다. ZITO/Ag/ZITO 다층막 필름의 면저항 및 투과도 특성은 적외선(열선)을 효과적으로 차단할 수 있기 때문에 고분자분산액정(polymer-dispersed liquid crystal, PDLC) 기반 스마트 윈도우 적용에 매우 유용함을 알 수 있었으며 이로 인해 에너지 절약형 스마트 유리로서의 응용도 가능할 것으로 판단된다. 제조된 ZITO/Ag/ZITO 다층막 투명전극을 적용한 2관능성 우레탄 아크릴레이트 기반 PDLC 시스템에 있어서 PDLC 층 두께 및 자외선(ultraviolet, UV) 세기 변화가 전기광학적 특성, 광중합 동력학 및 표면 형태학에 미치는 영향을 조사하였다. 15 ㎛의 PDLC 층 두께를 가지며 2.0 mW/c㎡의 UV 세기로 광경화된 PDLC 셀이 우수한 off-state 불투명도, 높은 on-state 투과도 및 양호한 구동 전압을 나타냈다. 또한, 본 연구에서 제조된 최적 조건의 PDLC 기반 스마트 윈도우는 광을 효율적으로 산란시킬 수 있는 2~5 ㎛ 크기의 양호한 마이크로 구조를 갖는 액정 droplet들이 형성되었으며, 이로 인해 우수한 최종 물성을 갖는 PDLC 셀이 제조되었다.

Hazards Caused by UV Rays of Xenon Light Based High Performance Solar Simulators

  • Dibowski, Gerd;Esser, Kai
    • Safety and Health at Work
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    • 제8권3호
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    • pp.237-245
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    • 2017
  • Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

외부활동에 따른 자외선 노출이 피부에 미치는 영향 연구 -피부물리치료를 위한 기초 연구- (A study on the effect of UV exposure on the skin due to external activities)

  • 이광재;최영인
    • 대한물리치료과학회지
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    • 제21권1호
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    • pp.37-43
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    • 2014
  • Background : The purpose of this study is to verify the type of influence on the skin color according to the photoaging symptoms depending on the degree of external activities among the factors that influence the skin due to UV exposure and to obtain the basic study data on the physical therapy of the skin. Methods : In this study, in order to investigate the type of influence on the skin color according to the photoaging symptoms when the body is exposed to the UV rays having various effects on our body, a study was conducted using questionnaires and skin color measurement tool targeting 20 male college soccer students with many external activities and the senior high school students who has relatively less external activities due to the preparation for college entrance. The skin color was measured and the results were compared. Result : In the test group having relatively higher external activities, while they had less use of the sunscreen, they had more degree of UV exposure, and for the recognition of ultraviolet hazard, more were aware that it was harmful. In addition, in the skin color measurement test conducted targeting the son and the father in order to investigate the association between the skin color and the genetic factors, the experimental group showed a significant difference(p<.05) but the control group did not show any significant difference(p>.05). Conclusion : Based on such study results, the UV exposure time and the use of sunscreen are thought to be an important factor in the skin care.

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자외선과 광 촉매제를 이용한 감귤껍질 농약제거공정의 최적화 (Optimum Processing Conditions for Pesticides Removal in Mandarine Orange Peel by Ultraviolet Rays and Photocatalytic Materials)

  • 김희선;한명륜;김애정;김명환
    • 산업식품공학
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    • 제15권1호
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    • pp.28-33
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    • 2011
  • UV-C와 -B type의 lamp를 이용한 혼합 자외선(UV)조사의 조사시간, 조사온도 및 광 촉매제인 $H_2O_2$의 분사농도변화를 이용하여 감귤껍질에 부착되어있는 농약을 제거하기 위한 공정의 최적화를 이루고자 하였다. Chloropyrifos에 대한 독립변수들의 영향력은 조사온도가 가장 컸으며 그 다음 조사시간, $H_2O_2$ 분사농도 순 이었다. Methidathion은 조사시간이 가장 컸으며 조사온도, $H_2O_2$ 분사농도 순으로 나타났다. EPN은 조사온도와 조사시간이 비슷하게 나타났고 $H_2O_2$ 분사농도가 가장 작았다. UV감귤껍질의 농약 잔존량이 가장 작게 나타난 처리조건으로 chloropyrifos와 EPN에 대한 최적조건으로는 조사시간 60분, 조사온도 $45^{\circ}C$, $H_2O_2$ 분사농도 1000 ppm으로 나타났다. 반면에 methidathion의 경우에는 최적조건으로는 조사시간 60분, 조사온도 $40^{\circ}C$, $H_2O_2$ 분사농도 1000 ppm으로 나타났다. 최적공정조건에서 chloropyrifos, methidathion 및 EPN의 잔존 량은 조사 전의 각각 46, 49 및 28% 수준이었다.