• Title/Summary/Keyword: ultraviolet protection

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화염감지기에 대한 고찰

  • Lee, Bok-Yeong
    • Fire Protection Technology
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    • s.13
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    • pp.18-26
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    • 1992
  • This report is explained about operating principles, characteristices of flame detectors. Flame detector is designed to detect the UV (Ultraviolet) and IR (Infrared) rediation produced by flaming involving carbonaceous materials.

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A Study on Function of Natural Dyeing with Cotton Fabrics Using Jeju scoria (제주 송이를 이용한 천연염색 면직물의 기능성 연구)

  • Im, Eun-Suk;Lee, Hye-Sun
    • Textile Coloration and Finishing
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    • v.23 no.3
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    • pp.179-186
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    • 2011
  • For the application of Jeju scoria scattered around the island as a natural dye, cotton fabrics were dyed with the dye and their properties were measured including dyeability, colorfastness, antibacterial activity, deodorization efficiency, ultraviolet protection, and far-infrared emission. The dyed cotton fabrics were in yellowish red and optimal dyeing conditions were obtained with a colorant concentration of 25%(o.w.b) at a temperature of $80^{\circ}C$ for the dyeing time of 120 minutes. The ratings of colorfastness to light, rubbing, perspiration, and washing were 8, 5, 5, and 4~5 respectively. After 15 wash cycles, colorfastness remained as much as 4~5 rating. The cotton fabric dyed with Jeju scoria demonstrated excellent antimicrobial activity and deodorization efficiency of 99.9% and 93.9% respectively. Ultraviolet protection factor was 50+. Far-infrared emission rate and far-infrared emission intensity were 90% and 362(W/$m^2{\cdot}{\mu}m$) respectively. The Jeju scoria can be introduced as a new colorant for the natural dyeing of cotton.

Effects of Enhanced Ultraviolet-B Radiation on Plants (오존층 파괴에 의한 자외선 증가가 식물에 미치는 영향)

  • Hak Yoon Kim;Moon Soo Cho
    • Journal of Bio-Environment Control
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    • v.10 no.3
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    • pp.197-206
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    • 2001
  • The depletion of stratospheric ozone is regarded as a major environmental threat to plant growth and ecosystem. The ozone depletion has caused plants to be exposed to an increased penetration of solar ultraviolet-B (UV-B) radiation in the 280-320 nm wavelength range. Enhanced UV-B radiation may have influence on plants biological functions in many aspects including inhibition of photosynthesis, DNA damage, lipid peroxidation, changes in morphology, phenology, and biomass accumulation. To cope with the damage by UV radiation, plants have evolved to have protective mechanisms, such as photorepair, accumulation of UV-absorbing compounds, leaf thickening and activation of antioxidative enzymes. The objective of this review is to address the effects of enhanced UV-B on plant growth, UV-B action mechanisms and protection and protection mechanisms in plants.

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Dyeing Property and Functionality of Silk Fabrics Dyed with Rhododedron brachycarpum Extracts (만병초 추출물에 의한 견직물의 염색성 및 기능성)

  • Kim, Sangyool
    • Journal of Fashion Business
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    • v.23 no.3
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    • pp.23-34
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    • 2019
  • The aim of this study is to explore the possibility utilizing Rhododedron brachycarpum as a new natural dye resource. It was dyed in silk fabric according to different dyeing conditions such as dye concentration, dye bath temperature, dyeing time and dye bath pH. The effect of the mordanting conditions were estimated as dyeability and color changes. Additionally, the colorfastness, antibacterial property, ultraviolet protection properties of the dyed and mordanted silk fabrics were examined. The water-soluble dye of Rhododedron brachycarpum extracted with distilled water was expressed as Yellow Red color. The dye-abilities of silk generally increased depending on the increasing values of dye concentration, dye bath temperature and dyeing duration. The highest K/S values were obtained at a dye concentration of 100% (v/v), a dye bath temperature of $90^{\circ}C$, a dyeing duration 120 minutes and a dyeing of pH 2. The light fastness of dyed and Cu mordanted silk fabrics were found to be 4 grade while Al, Fe mordanted silk fabrics were found to be 2~3 grade. The dry cleaning and rubbing fastness were excellent or good. The fade of washing fastness was not good, however, the stain of washing fastness was excellent. The dyed and Al, Cu mordanted silk fabrics indicated 99.9% reduction rate. The dyed and the mordanted fabrics showed very good ultraviolet protection factors.

A Study on The Natural Dyeing of Crataegi fructus Extracts (산사 추출물을 이용한 천연염색 연구)

  • Kim, Sangyool
    • Journal of Fashion Business
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    • v.23 no.4
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    • pp.100-111
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    • 2019
  • In this study, the dyeing properties and functionalities of Crataegi fructus extract were investigated for the purpose of application to new natural dye resources. The effects of dyeing conditions(concentration of dye, dye bath temperature, dyeing duration and dye bath pH) and mordanting on dye uptake and color changes were also examined. The study also estimated the colorfastness, antibacterial properties, and ultraviolet protection properties of the dyed and mordanted silk fabrics. The dye uptake increased in tandem with the dye concentration and dye bath temperature. The highest K/S values were obtained at the following conditions: a dye concentration of 100%(v/v), a dyeing period of 60 minutes, a dye bath temperature of $90^{\circ}C$, and a dyeing pH of 3. The colorfastness of the material when dry cleaned or rubbed ranged from good to excellent and fastness to light was rated at grade 2-3. The change in the color grade when exposed to washing was not good; however, the stain of washing fastness was good at a range of 4-5. In regards to the functional property aspects, the dyed and mordanted fabrics exhibited excellent results with a 99.9% reduction rate, and excellent ultraviolet protection factors.

A Test to Compare the Water Resistance Sun Protection Factor of General Water, Artificial Seawater, and Natural Seawater of Sunscreen (자외선 차단제의 일반 물, 인공 해수, 자연 해수의 내수성 차단지수를 비교하기 위한 시험)

  • Hyoung Hoon Hwang;Eun Young Kang;Su Yeong Kim;Hui Jeong Jung;Jun Seong Yang;Won Kyu Hong;Hong Suk Kim
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.49 no.4
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    • pp.349-354
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    • 2023
  • Sunscreen is a product that protects against ultraviolet rays by blocking and scattering ultraviolet rays, and has now become a daily necessity beyond cosmetics. Applying sunscreen is a common and easy way to prevent skin damage caused by ultraviolet rays. Due to its significance, the evaluation of sunscreen has evolved since its regulation by the FDA in 1978, progressing to standardized methods established by ISO. Additionally, to assess the loss of sunscreen due to activities such as water exposure or sweating, the Ministry of Food and Drug Safety in Korea and ISO have established protocols for evaluating the water-resistant sun protection factor (SPF). However, existing evaluations of water resistance have been mainly confined to test methods involving plain water, and methods accounting for the impact of seawater during activities like beach leisure, sports, and recreation are yet to be established. Based on the existing guidelines for testing the water-resistant UV protection index, this study compared the water-resistant UV protection index in water, artificial seawater (salt water) and natural seawater (sea water) to evaluate the UV protection index in real-world situations such as marine leisure, sports, and leisure activities. Through these results, we were able to compare the differences between water resistance sun protection index tests in ordinary water, artificial seawater, and natural seawater, and suggest a method for water resistance sun protection index tests using natural seawater.

Dyeing Fastness and Functional Properties of Cotton Dyed with Astringent Persimmon Juice

  • Jung, Jin-Soun
    • International journal of advanced smart convergence
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    • v.8 no.3
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    • pp.27-38
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    • 2019
  • I reviewed about dyeing fastness and functional properties of the non-mordant dyed cotton and iron mordant dyed cotton with astringent persimmon juice. In the UV-VIS spectrum of astringent persimmon juice, the maximum absorption wavelength of the juice was 272.0 nm, which was a characteristic peak of tannin. In dyeing fastness, light fastness of the non-mordant dyed cotton was a little low at grade 2~3. But by the iron mordant treatment, the light fastness was good at grade 4. Dry cleaning fastness to discoloration and contamination was excellent at grade 4~5 for both the non-mordant dyed cotton and iron-mordant dyed cotton. Their rub fastness were grade 3 and grade 2~3 respectively, in the dry condition, and grade 2~3 and grade 3 respectively, in the wet condition. In the perspiration fastness of the non-mordant dyed cotton, the discoloration from acidity and alkalinity was grade 3~4 and grade 3, respectively, and contamination from acidity and alkalinity was relatively good at grade 4. Meanwhile, in the perspiration fastness of the non-mordant dyed cotton, discoloration from acidity and alkalinity was fair, both recording grade 3~4, and contamination from acidity and alkalinity was very good, both recording grade 4~5. In the ultraviolet protection effect of the non-mordant dyed cotton and iron-mordant dyed cotton, the ultraviolet protection factor was both 50+, both of which showed an excellent ultraviolet blocking effect. And the protection rate of UV-A appeared 98.4% and 99.1%, respectively, and the protection rate of UV-B showed 98.7% and 99.2, respectively. In addition, both exhibited an excellent deodorization rate over 99.9% or more, irrespective of the passage of time. Also, both showed an excellent antimicrobial activity over 99.9% or more against Staphylococcus aureus and Klebsiella pneumoniae.

Characteristics of Environmental Solar Ultraviolet Irradiance

  • Sasaki, Masako;Oyanagi, Takehiko;Takeshita, Shu
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.154-157
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    • 2002
  • Direct, continuous, and accurate measurements of solar ultraviolet irradiance (290-400 nm: UVR) have been carried out since 1990, by using both band-spectral ultraviolet-B (290-320 nm: UV-B) and ultraviolet-A (320-400 nm: UV-A) radiometers at Tokai University in Hiratsuka, Japan (35$^{\circ}$N, 139$^{\circ}$E). From our observations, the following findings are provided: 1) an increasing trend in solar UV -B from Oct. 1990 to Sept. 2000; 2) a regional comparison of solar UVR in Japan; 3) the distinct characteristics of UV-B and UV-A irradiance, such as diffuse property, daily and seasonal variation; and 4) human body protection against solar UVR. An increasing 10-year trend in global solar UV - B in Hiratsuka corresponded to a decrease in the total ozone amount measured at Tsukuba (36$^{\circ}$N, 140$^{\circ}$E), giving supportive evidence for a direct link between these two parameters. Furthermore, a strong correlation was found between solar UV-B and total ozone amount from results of UVR measurements at four Tokai University monitoring stations dispersed throughout Japan. Additional results revealed different diffuse properties in global solar UV and in global solar total (300-3000 nm: Total) irradiances. For example, in the global UVR, the diffuse component was dominant: about 80 % independent of weather, with more than 60 % of global UV-B, and more than 50% of global UV-A with even a cloudless clear sky. On the other hand, the portion of the diffuse in the global total irradiance was very low, less than 10 % on a cloudless clear day. Daily and seasonal variations of UV -B and UV -A irradiances were found to be quite different, because of the marked dependence of UV -B irradiance on the atmospheric ozone amount. Moreover, UV -B irradiance showed large daily and seasonal variations: the ratio between maximum and minimum irradiances was more than 5. In contrast, the variation in UV-A was small: the ratio between maximum and minimum was less than 2. Three important facts are proposed concerning solar UVR protection of the human body: 1) the personal minimal erythema dose (MED); 2) gender based difference in MED values; and 3) proper colors for UVR protective clothing.

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Screening of Freshwater Microalgae for Resistance to Ultraviolet Radiation (자외선 차단능을 보유한 미세조류의 스크리닝)

  • Han, Mi-Ae;Han, Hye Jin;Jung, Moon Hee;Yoo, Rim Hwan;Hwang, Chae Eun;Myung, Su Hyun;Son, Yun Jin;Yoon, Young-Sil;Lee, Choul-Gyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.6 no.2
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    • pp.131-137
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    • 2014
  • Ultraviolet-B radiation (UV-B) in sunlight causes biological damages such as erythema and blister on skin. Microalgae have been in the limelight as an attractive feedstock for manufacturing functional materials. This study focused on screening microalga with protection ability against UV-B. The microalgae were isolated from local areas on April to June 2013 as well as June 2014. The cells were grown under continuous illumination from fluorescent lamps at $136.3{\pm}2.2{\mu}E/m^2/s$ in BG-11 medium at $15^{\circ}C$ for 12-14 days. The selected cells were spread on BG-11 agar and were exposed to UV-B (312 nm) for 20 and 25 minutes. The 13 strains among selected algae were classified. Among these, 9 strains were Scenedesmus sp. and the remains were Chlorella sp. Based on this study, it seems that Scenedesmus sp. and Chlorella sp. have resistibility against ultraviolet. These results will help to study on UV protection using microalgae.

Protective Measures From Solar Ultraviolet Radiation for Beach Lifeguards in Tuscany (Italy): Shade and Clothing Strategies

  • Daniele Grifoni;Giulio Betti;Andrea Bogi;Lucia Bramanti;Alessandra Chiarugi;Bernardo Gozzini;Marco Morabito;Francesco Picciolo;Francesco Sabatini;Lucia Miligi
    • Safety and Health at Work
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    • v.13 no.4
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    • pp.421-428
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    • 2022
  • Background: The exposure to solar ultraviolet radiation is a significant risk factor generally underestimated by outdoor workers and employers. Several studies have pointed out that occupational solar exposure increased eye and skin diseases with a considerable impact on the lives and productivity of affected workers. The main purpose of this study was to evaluate the effectiveness against ultraviolet radiation of some measures recently undertaken for the protection of lifeguards in a coastal area of Tuscany. Methods: Different shading structures (gazebos and beach umbrella) were tested during a sunny summer's day on a sandy beach by means of two radiometers; the UV protection offered by some T-shirts used by lifeguards was also tested in the laboratory with a spectrophotometer. Results: The analysed shading structures strongly reduced the ultraviolet radiation by up to 90%, however a not always negligible diffuse radiation is also present in the shade, requiring further protective measures (T-shirt, sunglasses, sunscreen, etc.); the tested T-shirts showed a very good-excellent protection according to the Australian/New Zealand standard. Conclusion: Results obtained in this study suggest how the adoption and dissemination of good practices, including those tested, could be particularly effective as a primary prevention for lifeguards who are subjected to very high levels of radiation for long periods.