Photocatalytic inactivation of bacteriophages by TiO2-coated glass plates under low-intensity, long-wavelength UV irradiation

2011 ◽  
Vol 10 (11) ◽  
pp. 1825 ◽  
Author(s):  
Hitoshi Ishiguro ◽  
Ryuichi Nakano ◽  
Yanyan Yao ◽  
Jitsuo Kajioka ◽  
Akira Fujishima ◽  
...  
Keyword(s):  
Uv Irradiation ◽  
Long Wavelength ◽  
Coated Glass ◽  
Low Intensity ◽  
Photocatalytic Inactivation ◽  
Glass Plates

The Influence of Hydrogen Donors on Breakage of Parental DNA Strands and on Biological Activity of Transforming BrU-DNA of B. subtilis after 302/313 nm Radiation

1974 ◽  
Vol 29 (1-2) ◽  
pp. 66-71
Author(s):  
Wolfgang Köhnlein
Keyword(s):  
Molecular Weight ◽  
Biological Activity ◽  
Uv Irradiation ◽  
Strand Breaks ◽  
Protective Agents ◽  
Long Wavelength ◽  
Hydrogen Donors ◽  
Dna Strands

Abstract Long wavelength UV irradiation (302/313 nm) of hybrid and bifilarly labeled BrU-DNA of B. subtilis results in a degradation of the molecular weight of BrU and of parental thymine con­ taining DNA strands. Hydrogen donors present during UV irradiation are able to prevent these “primary” and “secondary” strand breaks. The protection factors are especially large for secondary breaks in parental normal DNA. Through the action of protective agents the biological activity could not be restored. The generation of these primary and secondary strand breaks due to BrU incorporation and the action of hydrogen donors discussed.

Photocatalytic inactivation of Flavobacterium and E. coli in water by a continuous stirred tank reactor (CSTR) fed with suspended/immobilised TiO2 medium

2008 ◽  
Vol 58 (1) ◽  
pp. 247-252 ◽  
Author(s):  
Vered Cohen-Yaniv ◽  
Nava Narkis ◽  
Robert Armon
Keyword(s):  
Glass Beads ◽  
Stirred Tank ◽  
Continuous Stirred Tank Reactor ◽  
Stirred Tank Reactor ◽  
E Coli ◽  
Tank Reactor ◽  
Coated Glass ◽  
Log Reduction ◽  
Photocatalytic Inactivation ◽  
Continuous Stirred Tank

A photocatalytic continuous stirred tank reactor (CSTR) was built at laboratory scale to inactivate two environmental bacteria strains (Flavobacterium and E. coli) in tap water. Several parameters were found to impact reactor efficiency. Bacterial initial concentration is an important factor in inactivation rate. After 30 minutes of irradiation at 108–109 CFU mL−1 starting concentration, a >5 log reduction was achieved while at 104–106 CFU mL−1 only a 2 log reduction was observed. Water hardness and pH have an important influence on the photocatalytic inactivation process. Soft water, with low Ca+2 and Mg+2 at low pH ∼ 5.3 resulted in increased inactivation of Flavobacterium reaching >6 orders of magnitude reduction. E. coli and Flavobacterium at pH 5 were inactivated by 3 logs more as compared to pH 7 under similar conditions. pH below TiO2 isoelectric point (approximately 5.6) supports better contact between bacteria and anatase particles resulting in superior inactivation. TiO2 powder suspension was compared with immobilised powder in sol-gel coated glass beads in order to exclude the need for particles separation from the treated water. TiO2 suspension was more effective by 3 orders of magnitude when compared to coated glass beads. An interesting observation was found between the two bacterial strains based on their hydrophobicity/hydrophilicity balance. The more hydrophobic Flavobacterium compared to E. coli was inactivated photocatalytically by >3 logs more then E. coli in the first 30 minutes of irradiation interval. The results indicate the importance of the parameters involved in the contact between TiO2 particles and microorganisms that govern the succesful inactivation rate in CSTR.

Self-Cleaning Test of Doped TiO2-Coated Glass Plates under Solar Exposure

2009 ◽  
Vol 48 (2) ◽  
pp. 598-606 ◽  
Author(s):  
Jorge Medina-Valtierra ◽  
Claudio Frausto-Reyes ◽  
Jorge Ramírez-Ortiz ◽  
Gabriela Camarillo-Martínez
Keyword(s):  
Doped Tio2 ◽  
Coated Glass ◽  
Solar Exposure ◽  
Glass Plates ◽  
Self Cleaning

M-type atomic basic cell as a low intensity long wavelength infrared photodetector

Optik ◽  
2012 ◽  
Vol 123 (4) ◽  
pp. 362-365
Author(s):  
M. Zyaei ◽  
A. Rostami ◽  
H. Rasooli Saghai
Keyword(s):  
Infrared Photodetector ◽  
Long Wavelength ◽  
Low Intensity ◽  
Basic Cell ◽  
Long Wavelength Infrared

Impact surface fractures of glass-fiber/epoxy lamina-coated glass plates by small steel-ball

2010 ◽  
Vol 70 (14) ◽  
pp. 2056-2062 ◽  
Author(s):  
Nak-Sam Choi ◽  
Jae-Young Chang ◽  
Seung-Bum Kwak ◽  
Ja-Uk Gu
Keyword(s):  
Glass Fiber ◽  
Steel Ball ◽  
Coated Glass ◽  
Impact Surface ◽  
Glass Plates ◽  
Small Steel

Chemically deposited PbS thin film photo-conducting layers for optically addressed spatial light modulators

2014 ◽  
Vol 2 (43) ◽  
pp. 9132-9140 ◽  
Author(s):  
Tsofnat Safrani ◽  
Tatipamula Arun Kumar ◽  
Matvey Klebanov ◽  
Neta Arad-Vosk ◽  
Rotem Beach ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Tin Oxide ◽  
Lead Sulfide ◽  
Indium Tin Oxide ◽  
Spatial Light Modulators ◽  
Coated Glass ◽  
Light Modulators ◽  
Glass Plates ◽  
Semiconducting Thin Films

Lead sulfide semiconducting thin films were chemically deposited on indium tin oxide coated glass plates for use as photoreceptor layers in conjugation with optically addressed spatial light modulators (OASLMs).

Self-Cleaning Tests of Zn-Fe/Anatase-Coated Glass Plates under Direct and Diffuse Sunlight

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Jorge Medina-Valtierra ◽  
Jorge Ramírez-Ortiz ◽  
Claudio Frausto-Reyes
Keyword(s):  
Exposure Time ◽  
Solar Irradiation ◽  
Tio2 Films ◽  
Doped Tio2 ◽  
Diffuse Solar Radiation ◽  
Coated Glass ◽  
Solar Exposure ◽  
Typical Experiment ◽  
Glass Plates ◽  
Self Cleaning

Thin films of anatase (TiO2) doped with 1 wt. percent of zinc ferrite (ZnFe2O4) were formed on glass plates by deposition of a sol-gel mixture using an ultra-spinning technique. After the preparation, the TiO2 films with a thickness of 168-232 nm were investigated with respect to their UV absorption capability and photo-degradation of organic molecules. Microscope observations of the surface of TiO2 films showed that they exhibit a micro-granular surface. To test the self-cleaning properties of the doped TiO2 films, a layer of fluoranthene of around 6.5 mg was sprayed over the glass and then exposed to direct or diffuse solar radiation. While the coated-glass transparency was totally recovered at 88 h of direct solar exposure for the undoped anatase film, the covering of fluoranthene on the 1 wt. percent ZnFe2O4-doped TiO2 film was degraded totally at 52 h of exposure time. As complementary experiments, the same glass plates with metal oxide-doped anatase films, after spraying with a similar layer of the organic contaminant, were placed under diffuse sunlight. In a typical experiment, the covering of fluoranthene was degraded almost 100 percent at an exposure time of 48 days and the transparency of glass plates was recovered totally at 55 days of indirect solar exposure. A correlation was found between the weight losses of the solid contaminant and the intensity of the Raman vibration at 672 cm-1. It was found that under diffuse solar irradiation is possible to remove completely a fluoranthene layer generating an expected application of these active surfaces under extreme conditions.

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