• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.4 s.48
• /
• pp.445-448
• /
• 2004

Aging is divided into intrinsic aging and photo-aging. Intrinsic aging is naturally occurred as the time passed and photo-aging is induced by the UV radiation of skin. The main reason of aging is the free radicals and the degeneration of the cellular materials by free radicals. In this paper, we checked the anti-aging effects of Mallotus japonicus bark extracts. It has the ability to scavenge free radicals and the SOD like activity. Also, it reduced the cell damage by hydrogen peroxide treatment. Mallotus japonicus bark extracts showed the excellent activity on inhibiting the UV induced cell damage and DNA damage. In conclusion, Mallotus japonicus bark extracts can be used as active ingredients for anti-aging cosmetics.

• Clean Technology
• /
• v.22 no.2
• /
• pp.106-113
• /
• 2016

This study was performed to study the photocatalyst for controlling the pollutant such as CO, C₂H₅OH and H₂S by the UV light. This was shown in a catalyst having the same volume and the same surface area, that the structure in which the UV light to reach the interior structure exhibits more excellent activity. However, the activity of this activity of this photocatalyst removal of CO was very low. This problem can be solved by performing a reduction process by the addition of the precious metal series of Pt. Particularly, the amount of chemical species Pt⁰ incerased in the surface of Pt/TiO₂ photocatalyst through the reduction process, which make the reaction activity of photocatalyst excellent to the removal of the CO.

• Journal of the Korean Ceramic Society
• /
• v.52 no.6
• /
• pp.502-507
• /
• 2015

We examined the photo catalytic activity and catalytic recyclability of CdSe/graphene nanocomposites fabricated via modified hydrothermal technique. The prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), transmission electron microscopy (TEM), Raman spectroscopic analysis, and X-ray photoelectron spectroscopy (XPS). The photocatalytic behavior was investigated through decomposition of RBB as a standard dye under visible light radiation. Our results indicate that there is significant potential for graphene based semiconductor hybrids materials to be used as photocatalysts under visible light irradiation for the degradation of organic dyes from industry effluents.

• Rapid Communication in Photoscience
• /
• v.4 no.2
• /
• pp.41-44
• /
• 2015

Biomolecular photo-damaging activity of a water-soluble cationic porphyrin was examined using human serum albumin (HSA), a water-soluble protein as a target biomolecule model by a fluorometry. Dichlorophosphorus(V) tetraphenylporphyrin ($Cl_2P(V)TPP$), was synthesized and used as a photosensitizer. This porphyrin could bind to HSA and cause the photosensitized oxidation of HSA through the singlet oxygen generation and the oxidative photo-induced electron transfer (ET). Near infrared emission spectroscopy demonstrated the photosensitized singlet oxygen generation by this porphyrin. Decrement of the fluorescence lifetime of $Cl_2P(V)TPP$ by HSA supported the ET mechanism. Furthermore, the estimated Gibb's energy indicated that the ET mechanism is possible in the terms of energy. Because oxygen concentration in cancer cell is relatively low, ET mechanism is considered to be advantageous for photosensitizer of photodynamic therapy.

• The Journal of Korean Physical Therapy
• /
• v.11 no.2
• /
• pp.5-9
• /
• 1999

The electromagnetic agent used in physical therapy rely far their effects on tissue heating and photo reaction of the body, Infrared has a thermal and analgesic effect, Ultra violet produces direct photo chemical reaction when it interacts with the body. Laser has broad effect on medicine, Ten ding Diancibo Pu (TDP) is in the infrared ray. The wave range is 20,000-250,000, as a far infrared. The effects of the TDP are number of white and red blued cell, capacity of animal immunization activity of enzyme in the organ and blood sugar density.

• Transactions of the Korean hydrogen and new energy society
• /
• v.1 no.1
• /
• pp.9-14
• /
• 1989

Mixed photocatalyst containing cadmium sulfide and zinc sulfide was prepared on silica gel powder and Nafion film. Photo-irradiation of aqueous mixture containing the photocatalysis generated hydrogen by water cleavage reaction. Use of sodium sulfide as sacrificial reagent help the photo-reaction. Evolution of the hydrogen was measured by gas chromatographic analysis. Composition of the catalyst was determined by atomic absorption spectrophotometer. 0.2 mL of of hydrogen was generated per hour. The maximun catalytic activity was obtained after 8-12 hours later. Hydrogen generation efficiency by the two different catalytic system was compared and showed that the Nafion-based catalyst is more efficient than the silicagel-based catalyst for the photoreaction.

• Transactions on Electrical and Electronic Materials
• /
• v.2 no.2
• /
• pp.37-41
• /
• 2001

Photo catalytic characteristics of nano-sized TiO$_2$ powder with rutile phase produced using homogeneous precipitation process at low temperatures (HPPLT) were compared with those of commercial P-25 powder by Degussa Co. The TiO$_2$ powder by HPPLT showed very higher photoactivity in the removal rate, showing lower pH values in the solution, than the P-25 powder when eliminating metal ions such as Pb and Cu from aqueous metal-EDTA solutions. This can be inferred the more rapid photo-oxidation or -reduction of metal ions from the aqueous solution, together with relatively higher efficiencies in the use of electron-hole pair formed on the surface of TiO$_2$ particle, under UV light irradiation. Also, in the view of the TiO$_2$ particle morphology, compared to the well-dispersed spherical P-25 particle, the agglomerated TiO$_2$ particle by HPPL T consists of acicular typed primary particle with the thickness ranged of 3∼7 nm, which would be more effective to the photocatalytic reactions without electron-hole recombination on the surface of the TiO$_2$ particle under the UV light irradiation. It is, therefore, thought that the higher photo activity of the rutile TiO$_2$ powder by HPPLT in the aqueous solutions resulted from having its higher specific surface area as well as acicular shape primary particle with very thin thickness.

• Journal of Digital Convergence
• /
• v.14 no.3
• /
• pp.337-344
• /
• 2016

For the past half century, researches on human psychology have witnessed the flourish of various research tools in this area. Many psychological measures were developed to get objectified data and this trend has lead to the abundance of quantified results. However, considering subjectiveness and refinements of human experience, the research focused on individual's unique perspectives and explanations is needed also. In this vein, this study proposed the usefulness of photography as a research tool for human psychology. With the wide spread of smart phone, taking photo became the everyday activity for modern people and also a part of a public art. If photo could play an efficient and unique role to study human psychology, the depth and width of human understanding might change dramatically in positive way. Two friendship photos were presented to suggest the possibility of photo as a research tool and final considerations of using photo were suggested briefly.

• Elastomers and Composites
• /
• v.44 no.3
• /
• pp.290-298
• /
• 2009

In this paper, the Fe-activated carbon fiber (ACF)/$TiO_2$ composite catalysts were prepared by a sol-gel method. The synthesized photocatalysts were used for the photo degradation of Methylene blue solution under UV light. From Brunauer-Emmett-Teller measurements (BET) data, it was shown the blocking of the micropores on the surface of ACF by treatment of Fe and Ti compound. As shown in SEM images, the ferric compounds and titanium dioxides were fixed onto the ACF surfaces. The result of X-ray powder diffraction showed that the crystal phase contained a mixing anatase and rutile structure and the 'FeO+$TiO_2$' from the composites. The EDX spectra for the elemental analysis showed the presence of C, O, and Ti with Fe peaks. Degradation activity of MB could be attributed to +OH radicals derived from electron/hole pair's reactions due to photolysis of $TiO_2$ and photo-Fenton effect of Fe.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.8
• /
• pp.1738-1742
• /
• 2009

Nanocrystalline Zn$Fe_2O_4$ oxide-semiconductor with spinel structure was synthesized by the polymerized complex (PC) method and investigated for its photocatalytic and photoelectric properties. The observation of a highly pure phase and a lower crystallization temperature in Zn$Fe_2O_4$ made by PC method is in total contrast to that was observed in Zn$Fe_2O_4$ prepared by the conventional solid-state reaction (SSR) method. The band gap of the nanocrystalline Zn$Fe_2O_4$ determined by UV-DRS was 1.90 eV (653 nm). The photocatalytic activity of Zn$Fe_2O_4$ prepared by PC method as investigated by the photo-decomposition of isopropyl alcohol (IPA) under visible light (${\geq}$ 420 nm) was much higher than that of the Zn$Fe_2O_4$ prepared by SSR as well as Ti$O_{2-x}N_x$. High photocatalytic activity of Zn$Fe_2O_4$ prepared by PC method was mainly due to its surface area, crystallinity and the dispersity of platinum metal over Zn$Fe_2O_4$.