• Title/Summary/Keyword: UV treatment

Search Result 1,305, Processing Time 0.036 seconds

A Study on Degradation of Nonylphenol Polyethoxylate Metabolites Using Uv / Photocatalytic Silicagel Treatment

  • Asano, Masahiro;Kishimoto, Naoyuki;Jiku, Fumihiko;Somiya, Isao
    • Journal of Wetlands Research
    • /
    • v.9 no.1
    • /
    • pp.99-105
    • /
    • 2007
  • Nonylphenol polyetoxylates (NPnEOs) metabolites; nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenoxyacetic acid (NPEC) (collectively referred to "NPE-c") were examined for their degradations by using of lab-scale UV/photocatalytic silicagel (ultraviolet photocatalytic degradation in the presence of silicagel coated with titanium dioxide as a catalyst) reactor. NPE-c degradations by UV/photocatalytic silicagel treatment reached approximately 85-93 % after 40 min irradiation independently of its initial concentration (between ca. 0.5 and 2.0mg/l). Any intermediates under the NPE-c degradation were not identified by GC/MS sample analysis. Degradations of NPE-c were followed pseudo first-order kinetics. Then, the effectiveness of UV/photocatalytic silicagel treatment for degradation of NPE-c was in the order of NPEC > NP > NP1EO.

  • PDF

Beneficial Effect of an Agar Mask against Skin Damage Induced by UV Exposure in SKH-1 Hairless Mice (UV조사에 의해 유발된 SKH-1 hairless 마우스의 피부노화에 미치는 한천마스크의 개선효과)

  • Song, Bo Ram;Kim, Ji Eun;Yun, Woo Bin;Lee, Mi Rim;Choi, Jun Young;Park, Jin Ju;Kim, Dong Seob;Lee, Chung Yeoul;Lee, Hee Seob;Lim, Yong;Jung, Min Wook;Kim, Bae Hwan;Hwang, Dae Youn
    • Journal of Life Science
    • /
    • v.27 no.9
    • /
    • pp.975-985
    • /
    • 2017
  • To investigate the beneficial effects of an agar gel mask (AGM) on UV-induced photoaging, SKH-1 hairless mice were treated with a topical application of AGM and an AGM dipped in essence (AGMdE). The mice were divided into an no radiation group, UV + AGM, UV + AGMdE, and UV + vehicle (PBS) treatment groups. Alterations in skin wrinkles, skin phenotype, histological structures, oxidative status, and toxicity were then evaluated during 4 weeks of exposure. The topical application of AGM and AGMdE inhibited wrinkle formation, suppressed the erythema index, prevented transepidermal water loss, and enhanced skin hydration. In addition, epidermal thickness recovered to a similar level as that in the no irradiation group in the UV + AGM and UV + AGMdE treatment groups compared with the UV + vehicle (distilled water) group. Furthermore, the expression levels of matrix metalloproteinase-1 (MMP-1) and tyrosinase were reduced in the UV + AGM and UV + AGMdE treatment groups, although the highest level varied. Moreover, superoxide dismutase (SOD) activity was significantly lower in the UV + AGM and UV + AGMdE treatment groups as compared with the UV + vehicle group. No significant alterations induced by most toxic compounds were measured in serum biochemical markers and liver and kidney histological features of the UV + AGM and UV + AGMdE treatment groups. These results suggest that AGM may protect against skin aging by regulating skin morphology, histopathological structures, and oxidative conditions.

Preparation of UV protective cotton fabrics by novel UV-curing technique - Using a photocrosslinkable polymer, poly(ethylene glycol) dimethacylate -

  • Kim, Sin-Hee
    • Journal of Fashion Business
    • /
    • v.11 no.6
    • /
    • pp.52-61
    • /
    • 2007
  • To increase the ultraviolet radiation (UVR) protection of cotton fabric, ultraviolet protection (UVP) materials were treated onto cotton fabric using a new technique, UV-curing. A photocrosslinkablepolymer, poly(ethylene glycol) dimethacrylate was used as a UV-curable resin in the presence of a small amount of photoinitiator. Two kinds of UVP materials were used, UV-absorber, 2,2'-dihydroxy-4-methoxy benzophenone, and UV-scatterer, $TiO_2/ZnO$ Pad-dry-cure method in employing these materials onto cotton was also conducted to compare the effectiveness and the washfastness of UVP treatment between curing methods. UVP treated cotton fabric showed a moderate increase in UVP in case of 2,2'-dihydroxy-4-methoxy benzophenone treatment and a high increase in case of $TiO_2/ZnO$. UV-curing method increased the washfastness of UVP property of $TiO_2/ZnO$ treated cotton fabrics. However, in case of 2,2'-dihydroxy-4-methoxy benzophenone, similar wash fastnesses of UV-cured and pad-dry-cured cotton were observed. It can be presumed that 2,2'-dihydroxy-4-methoxy benzophenone was not significantly affected by water since its hydrophobicity. In short, UV-curing of UVP materials onto cotton was successfully done, and treated cotton fabrics showed the increased UVP properties and an increased washfastness in some extent.

Study on CFD Methodology for a Open Channel Type UV Reactor (전산유체역학을 활용한 개수로형 UV소독장비의 해석기법 연구)

  • Hwang, Woochul;Bak, Jeong-Gyu;Kim, Hyunsoo;Lee, Kunghyuk;Cho, Jinsoo
    • The KSFM Journal of Fluid Machinery
    • /
    • v.18 no.2
    • /
    • pp.54-59
    • /
    • 2015
  • The performance of UV reactor which is used in water treatment is strongly affected by UV fluence rate and water flow in the UV reactor. Therefore, CFD tools are widely used in designing process of UV reactors. This paper describes the development of a computational fluid dynamics (CFD) methodology that can be used to calculate the performance of open channel type UV reactor used in wastewater treatment plant. All computations were performed using commercial CFD code, CFX, by considering three dimensional, steady, incompressible flow. The Eulerian-Eulerian multi-phase method were used to capture the water-air interface. The MSSS model, provided by UVCalc3D, was used to calculate the UV intensity field. The numerical predictions and calculated UV Dose were compared with experimental dataset to validate the CFD methodology. The reactor performance based on MS2 log reduction was well matched with measurements within 6%.

A Study on the UV Intensity Models and their Affecting Factors (자외선 강도 산정 모델과 영향 인자에 관한 연구)

  • Kim, Dooil;Choi, Younggyun;Kim, Sunghong
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.22 no.4
    • /
    • pp.421-427
    • /
    • 2008
  • UV disinfection is widely used in water treatment facilities and wastewater treatment plant because of its effectiveness to removal of pathogen and Giardia which is resistant to traditional chemical disinfection. As a design and performance tool of UV disinfection system, 3 dimensional UV intensity models were composed and simulated to compare each other and to find affecting factors in this study. Reflection, refraction and absorption are important parameters in UV intensity model and MPSS and MSSS model can reflect these parameters while LSI model can not. Absorption is the most important parameters among the reflection, refraction, absorption and shadowing so, this should not be neglect. Based on this simulation, shadowing effect is negligible when the number of installed lamp is a few but, this effect can not be neglectable when the number of installed lamp is quite a few. The errors according to shadowing effect is increased as the number of lamp installed increased.

The Coating Performance of UV Curable Urethane Acrylate Coatings for Fancy Veneer Overlayed Plywood Flooring

  • Lee, Byoung-Hoo;Kim, Hyun-Joong;Lee, Young-Kyu
    • Journal of the Korean Wood Science and Technology
    • /
    • v.32 no.6
    • /
    • pp.23-35
    • /
    • 2004
  • The goal of study was to investigate the influence of the acrylated urethane oligomer on mechanical properties, the chemical resistance and thermal resistance of the UV curable urethane acrylate coatings for fancy veneer overlayed plywood flooring. The pencil hardness and abrasion resistance of the coated fancy veneer overlayed plywood floorings increased with increasing the acrylate functionality of the acrylated urethane oligomer. In the case of the UV cured film containing hexa-functional acrylated aliphatic urethane oligomer, high discoloration of the coated fancy veneer overlayed plywood flooring was observed near the cracks at the beginning of the chemical treatment. In this study, it was found that the degradation of the UV cured film caused by an alkaline reagent was higher than that of the UV cured film caused by an acidic treatment.

Comparative Studies Of the $UV/H_2O_2,\;UV/TiO_2/H_2O_2$ and Photo-Fenton Oxidation for Degradation of Citric Acid ($UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법에 의한 Citric Acid의 분해효율 비교)

  • Seo, Min-Hye;Cho, Soon-Haing;Ha, Dong-Yun
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.28 no.4
    • /
    • pp.429-437
    • /
    • 2006
  • To establish the efficient treatment technology of chemical cleaning wastewater from power plant, several AOPs($UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation) were investigated. Treatment efficiencies and the electrical energy requirements based on the EE/O parameter(the electrical energy, required per order of pollutant removal in $1m^3$ wastewater) were evaluated. TOC removal efficiencies of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation at the optimum conditions were 95.5%, 92.3%, 91.5%, respectively. The electrical energy requirements of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation were $11.26kWh/m^3,\;3.85kWh/m^3,\;0.799kWh/m^3$, respectively. From these results, it could be concluded that all of the three oxidation processes were effective for the degradation of citric acid. Considering the treatment efficiency and economical aspect, photo-Fenton oxidation was the most efficient treatment process among the three processes tested.

Study on Characteristic by ITO Surface Treatment and Cathode Change of Organic Light Emitting Diodes (ITO 표면 처리와 음전극 변화에 따른 OLEDs의 특성 연구)

  • Kim, Doo-Seok;Jang, Yoon-Ki;Kwon, Young-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.12
    • /
    • pp.1143-1147
    • /
    • 2005
  • In this study, we report an improved efficiency of Organic light emitting diodes(OLEDs), using $UV/O_3$ treated anode and different cathode. We investigated the efficiency of OLEDs by $UV/O_3$ treatment of ITO surface. We Performed $UV/O_3$ treatment and found that $UV/O_3$ treatment enhanced the performance of OLEDs. The fundamental structure of the OLEDs was ITO $anode/{\alpha}-NPD/Alq_3/Al$ or Li:Al cathode. The Li:Al can improve the OLEDs efficiency dramatically in cathode because it has lower work function than Al. Current-voltage, Luminance-voltage characteristics and luminance efficiency were measured at room temperature.

The Optical Property of Plasma-treated ZnO Nanorods (플라즈마 처리한 ZnO 나노막대의 광학적 특성)

  • Cho, Hyun-Min;Yu, Se-Gi;Cho, Jae-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.22 no.3
    • /
    • pp.230-234
    • /
    • 2009
  • Hydrogen and Oxygen plasma treatments have been done on sonochemical grow ZnO nanorods by varying treatment temperature and time, The changes(position and intensity) in ultraviolet(UV) peaks and green peaks of photoluminescence(PL) spectroscopy have been measured, Experimental results showed; i) in the case of hydrogen plasma treatment, the blue shift of UV peak and the increase of PL intensity of the UV peak were observed as the increase of the process time and temperature, ii) in the case of oxygen plasma treatment, the red shift of green peak was observed and the ratio of $I_{Green}/I_{UV}$ was also increased, as the increase of the process time and the temperature.

Stability Assessment of Ivory Materials by Cleaning Agents (세척제에 의한 상아류 유물의 안정성 평가 연구)

  • Kang, Dai Ill;Lee, Byeong Ju;Lee, Hee Jung
    • Journal of Conservation Science
    • /
    • v.28 no.3
    • /
    • pp.229-233
    • /
    • 2012
  • This research was to evaluate conservational stability of cleaning treatment and color recovery by weak acid treatment on ivory. Before this experiment, had an ivory identification such as black light and schreger angle to find whether it is authentic or not. In wet cleaning treatment on ivory, used polar solvents such as distilled water, acetone, ethyl alcohol and acetic acid which usually used for cleaning ivory and bones. After cleaning took a experiment to evaluate conservational stability in surface observation, calculate weight and color difference. Following these results, these polar solvents were stable on the ivory samples. On the other hand, in weak acid treatment, used samples that were exposed by UV-A, UV-B, UV-C for 1 weeks, to restore its color from changed to original color. After treatment, found tiny cracks and exfoliation on the surface. Moreover, the color changed when it is treated by lemon juice, so, it is impossible to adapt.