• Title/Summary/Keyword: Light activation

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Studies on Photocatalytic Thin Films($TiO_2$, TiO-N) Manufactured by DC Magnetron Sputtering Method and it's Characteristics for Removal of Pollutants (DC 마그네트론 스퍼터링법을 이용한 광촉매박막($TiO_2$, TiO-N)제조 및 오염물질 제거에 관한 연구)

  • Jeong, Weon-Sang;Park, Sang-Weon
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.59-66
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    • 2005
  • [ $TiO_2$ ] was deposited by DC magnetron sputtering on glass surface under various sputtering parameters such as discharge power($0.6{\sim}5.2\;kW$, substrate temperature($R.T{\sim}350^{\circ}C$), Ar and $O_2$ flow ratio with $0{\sim}50\;sccm$($Ar+O_2$ 90 sccm) and about 1 mtorr of pressure. TiO-N thin film was prepared under same sputtering conditions for $TiO_2$ thin film except flow ratio($Ar+O_2+N_2$ 90 sccm). The sheet resistance of thin films deposited under these parameters was measured to analyze electronic characteristic and thin film's thickness(${\alpha}$-step), surface roughness(AFM) and formation construction(FE-SEM, XRD) were also measured to draw optimal sputtering parameters. In order to evaluate photo-activity of thin film($TiO_2$, TiO-N) made in optimal parameters for removal of pollutants, toluene among VOCs and Suncion Yellow among reactive dyes were chosen to probe organic compounds for photo-degradation. It was shown that the photo-catalytic thin films had a significant photo-activation for the chosen contaminants and especially TiO-N thin film showed maximum efficiency of 33% for toluene(5 ppm) removal in visible-light range.

The Effect of Bu-Zhong-Yi-Qi-Tang on Epidermal Melanocytes in Ultraviolet B-irradiated Mice (마우스에서 보중익기탕이 자외선 B 조사에 의한 표피멜라닌세포 변화에 미치는 영향)

  • Lee, Hae-June;Kim, Hwan-Sung;Park, Young-Jong;Kim, Joong-Sun;Moon, Chang-Jong;Kim, Jong-Choon;Bae, Chun-Sik;Jo, Sung-Kee;Kim, Sung-Ho
    • Journal of Radiation Protection and Research
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    • v.33 no.3
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    • pp.87-91
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    • 2008
  • We induced the activation of melanocytes in the epidermis of C57BL/6 mice by ultraviolet B (UVB) irradiation and observed the effect of Bu-Zhong-Yi-Qi-Tang (BZYQT) on the formation, and decrease of UVB-induced epidermal melanocytes. C57BL/6 mice were irradiated by UVB $80\;mJ/cm^2$ (0.5 mW/sec) daily for 7 days, and BZYQT was intraperitoneally or topically applied pre- or post-irradiation. For the estimation of change of epidermal melanocytes, light microscopic observation with dihydroxyphenylalanine (DOPA) stain was performed. Split epidermal sheets prepared from the ear of untreated mice exhibited 11-16 melanocytes/$mm^2$, and one week after UV irradiation, the applied areas show an increased number of strongly DOPA-positive melanocytes with stout dendrites. But intraperitoneal or topical treatment with BZYQT before each irradiation interrupted UVB-induced pigmentation and resulted in a marked reduction in the number of epidermal melanocytes as compared to radiation control skin. The number and size of DOPA-positive epidermal melanocytes were also significantly decreased in intraperitoneally injected or topically applicated group after irradiation with BZYQT at 3rd and 6th weeks after irradiation. The present study suggests the BZYQT as inhibitor of UVB-induced pigmentation and depigmenting agent.

MLCK and PKC Involvements via Gi and Rho A Protein in Contraction by the Electrical Field Stimulation in Feline Esophageal Smooth Muscle

  • Park, Sun-Young;Shim, Jae-Ho;Kim, Mi-Na;Sun, Yih Hsiu;Kwak, Hyun-Soo;Yan, Xiangmei;Choi, Byung-Chul;Im, Chae-Uk;Sim, Sang-Soo;Jeong, Ji-Hoon;Kim, In-Kyeom;Min, Young-Sil;Sohn, Uy-Dong
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.1
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    • pp.29-35
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    • 2010
  • We have shown that myosin light chain kinase (MLCK) was required for the off-contraction in response to the electrical field stimulation (EFS) of feline esophageal smooth muscle. In this study, we investigated whether protein kinase C (PKC) may require the on-contraction in response to EFS using feline esophageal smooth muscle. The contractions were recorded using an isometric force transducer. On-contraction occurred in the presence of $N^G$-nitro-L-arginine methyl ester (L-NAME), suggesting that nitric oxide acts as an inhibitory mediator in smooth muscle. The excitatory composition of both contractions was cholinergic dependent which was blocked by tetrodotoxin or atropine. The on-contraction was abolished in $Ca^{2+}$-free buffer but reappeared in normal $Ca^{2+}$-containing buffer indicating that the contraction was $Ca^{2+}$ dependent. 4-aminopyridine (4-AP), voltage-dependent $K^+$ channel blocker, significantly enhanced on-contraction. Aluminum fluoride (a G-protein activator) increased on-contraction. Pertussis toxin (a $G_i$ inactivator) and C3 exoenzyme (a rhoA inactivator) significantly decreased on-contraction suggesting that Gi or rhoA protein may be related with $Ca^{2+}$ and $K^+$ channel. ML-9, a MLCK inhibitor, significantly inhibited on-contraction, and chelerythrine (PKC inhibitor) affected on the contraction. These results suggest that endogenous cholinergic contractions activated directly by low-frequency EFS may be mediated by $Ca^{2+}$, and G proteins, such as Gi and rhoA, which resulted in the activation of MLCK, and PKC to produce the contraction in feline distal esophageal smooth muscle.

Ethylenediamine Complex for Stabilization of Omeprazole (오메프라졸의 안정화를 위한 에칠렌디아민 복합체 개발)

  • Oh, Sea-Jong;Kim, Eun-Young;Kim, Kil-Soo;Kim, Yuon-Jeung;Lee, Gye-Ju
    • Journal of Pharmaceutical Investigation
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    • v.25 no.1
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    • pp.9-17
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    • 1995
  • To stabilize omeprazole(OMP), ethylenediamine(ED) complex of omeprazole(OMPED) was prepared by reaction between OMP and ED in methanol, and the complex formation was confirmed by the instrumental analysis, i.e., IR, DSC, EA, NMR, MS and XRD. The rates of decomposition of OMP and OMPED in aqueous solution and the shelf lives at standard temperature were measured by accelerated stability analysis. The results are summarized as follows; The mole ratio of OMP and ED in OMPED complex is 1:1, the energy of formation within OMPED might be combined between polar imidazole group of OMP with induced a dipole amine group in the readily polarizable ED molecule. At standard temperature the degradation rate constant of OMP in aqueous solution is $2.540{\times}10^{-2}\;hr^{-1}$ and the shelf life is 4.15 hrs, and in the case of OMPED the degradation rate constant is $7.986{\times}10^{-4}\;hr^{-1}$ and the shelf life is 131.96 hrs. So, the OMPED has about 31 times longer shelf life than OMP. The activation energy of OMP and OMPED are 5.23 and 18.55 kcal $mole^{-1}$ respectively. The stability of OMP is dependent chiefly on pH in the solutions and it decomposes readily in acidic medium by hydrogen ion catalized reaction but becomes stable beyond pH 9.0. In case of the ED-complex, OMPED is stable in neutral as well as in dilute acidic solutions even in pH 6, OMPED is very stable to light(UV), that is, the rate constant and shelf life of OMP are $k=1.0188{\times}10^{-2}\;day^{-1}$, $T_{90%}=4.5 \;days$, on the other hand, the those of OMPED are $k=7.138{\times}10^{-4}\;day^{-1}$, $T_{90%}=64.1\;days$, respectively. From the above results, it is thought that new dosage forms could be developed by using the OMPED as a potential OMP complex.

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The Effect of Initial pH and Dose of $TiO_2$ on Chloroform Removal in Photocatalytic Process using Compound Parabolic Concentrator Reactor System (CPCs를 이용한 $TiO_2$ 광촉매반응공정에서 초기 pH와 촉매농도가 클로로포름 분해에 미치는 영향)

  • Cho, Sang-Hyun;Cui, Mingcan;Nam, Sang-Geon;Jung, Hee-Suk;Khim, Jee-Hyeong
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.12
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    • pp.1147-1153
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    • 2010
  • To evaluate the solar photocatalytic degradation efficiency of chloroform in a real solar-light driven compound parabolic concentrators (CPCs) system, $TiO_2$ was irradiated with a metalhalide lamp (1000 W), which has a similar wavelength to sunlight. The results were applied to a pilot scale reactor system by converting the data to a standardized illumination time. In addition, the effects of initial pH and the $TiO_2$ dose on the photocatalytic degradation of chloroform were investigated. The results were compared with the specific surface area (S.S.A) and particle size of $TiO_2$, which changed according to the pH, to determine the relationship between the S.S.A, particle size and the photocatalytic degradation of chloroform. The experiment was carried out at pH 4~7 using 0.1, 0.2, 0.4 g/L of $TiO_2$. The particle size and specific surface area of $TiO_2$ were measured. There was no significant difference between the variables. However, pH affects the particle size distribution and specific surface area of $TiO_2$. Inaddition, the activation of a photocatalyst did not show a linear relationship with the specific surface area of $TiO_2$ in the photocatalytic degradation of chloroform.

Study on Oxidation Properties of Biodiesel Blended Fuels according to Storage Circumstances (저장 환경에 따른 바이오디젤 혼합연료의 산화특성 규명 연구)

  • Min, Kyong-Il;Yim, Eui-Soon;Jung, Chung-Sub;Kim, Jae-Kon;Na, Byung-Ki
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.4
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    • pp.701-714
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    • 2013
  • Recently, due to the activation policy of biodiesel, the blending biodiesel to petroleum product is increasing. Low-temperature fluidity and oxidation stability are the most significant issues to the marketers and end users of biodiesel. Thus, the way to control the quality of biodiesel blended fuels was investigated by duplicating the real storage situation of biodiesel blended fuels and evaluating the effect of oxidation trend and quality degradation. From the results of oxidation degradation test of biodiesel blended fuels, no special quality degradation has been observed through the evaporation for 18 weeks in a summer season under a storage circumstance without exposure to the sun light. However, the severe quality degradation was observed in PE vessel in only 2 weeks of storage. This oxidation degradation was also verified with FT-IR spectrum change. However, the special symptom cannot be distinguished by the quality test because the quality specifications were satisfied despite of the drastic oxidation degradation. Namely, the problem in a vehicle could be occurred by oxidation materials(polymer, organic acid. etc.) under oxidation even though it satisfied the quality specification.

A Study on the Activation of Cartoon for the elderly in Culture and Art Education : Focused on the Case Analyses of Participants (문화예술교육에 있어서의 노인만화 수업 활성화 방안 연구 -참여 노인들의 사례분석을 중심으로-)

  • Kwon, Kyoung-min;Yang, Jung-bin
    • Cartoon and Animation Studies
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    • s.47
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    • pp.171-191
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    • 2017
  • In recent years, artistic programs considering both physical and psychological changes in old age have been implemented in various fields. These programs include participatory activities such as painting, play, singing, photography, dance, cartoon animation and so on. It is known that culture and art education programs lead people to emotional growth and social interaction. In particular, culture and art education for the elderly tends to affect positively on the quality of life. However, there are still lack of teaching methods and curriculums in the filed. It is considered that cartoon has a great potential as a teaching method of culture and art education for elderly. This study aims to discuss ways to vitalize the role of cartoon using the qualitative data of four elderly participants in culture and art education programs. The case study analyses reveled that cartoon program for the elderly not only plays a role to make their daily lives more enthusiastic but also provides a social passage to communicate to world. The Cartoon program designed for the elderly was a tool to reveal their inner world to others, and shed new light on their past memories, and long for the precious moments in life. At the same time, it was a meaningful time to lessen the depth of loneliness in old age, and even to heal their physical disability and emotional conflicts. The hardest part of drawing an cartoon was when it did not turn out as they wished. Based on the study results, the researchers explored the therapeutic usefulness of cartoon for the elderly, and discussed the ways to activate it in the field of elderly welfare.

Growth and optical characterization of $CuInSe_2$ single crystal thin film for solar cell application (태양전지용 $CuInSe_2$단결정 박막 성장과 광학적 특성)

  • 백승남;홍광준
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.12 no.4
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    • pp.202-209
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    • 2002
  • The stochiometric mix of evaporating materials for the $CuInSe_2$single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CuInSe_2$compound crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $620^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CuInSe_2$single crystal thin films measured from Hall effect by van der Pauw method. From the photocurrent spectrum by illumination of perpendicular light on the c-axis of the $CuInSe_2$single crystal thin film, we have found that the values of spin orbit splitting $\Delta$So and the crystal field splitting $\Delta$Cr. From the photoluminescence measurement on $CuInSe_2$single crystal thin film, we observed free exciton ($E_x$) existing only high quality crystal and neutral bound exciton ($A^{\circ}$, X) having very strong peak intensity. Then, the full-width-at-half-maximum (FWHM) and binding energy of neutral donor bound exciton were 7 meV and 5.9 meV, respectivity. By haynes rule, an activation energy of impurity was 59 meV.

Optical Properties of $ZnIn_2S_4/GaAs$ Epilayer Grown by Hot Wall Epitaxy method (Hot Wall Epitaxy (HWE)에 의한 성장된 $ZnIn_2S_4/GaAs$ 에피레이어의 광학적 특성)

  • Hong, Gwang-Jun;Lee, Gwan-Gyo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.175-178
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    • 2004
  • The stochiometric mixture of evaporating materials for the $ZnIn_2S_4$ single crystal thin film was prepared from horizontal furnace. To obtain the $ZnIn_2S_4$ single crystal thin film, $ZnIn_2S_4$ mixed crystal was deposited on throughly etched semi-insulating GaAs(100) in the Hot Wall Epitaxy(HWE) system. The source and substrate temperature were $610^{\circ}C$ and $450^{\circ}C$, respectively and the growth rate of the $ZnIn_2S_4$ sing1e crystal thin film was about $0.5\;{\mu}m/hr$. The crystalline structure of $ZnIn_2S_4$ single crystal thin film was investigated by photoluminescence and double crystal X-ray diffraction(DCXD) measurement. The carrier density and mobility of $ZnIn_2S_4$ single crystal thin film measured from Hall effect by van der Pauw method are $8.51{\times}10^{17}\;cm^{-3}$, $291\;cm^2/V{\cdot}s$ at $293_{\circ}\;K$, respectively. From the photocurrent spectrum by illumination of perpendicular light on the c - axis of the $ZnIn_2S_4$ single crystal thin film, we have found that the values of spin orbit splitting ${\Delta}S_O$ and the crystal field splitting ${\Delta}Cr$ were 0.0148 eV and 0.1678 eV at $10_{\circ}\; K$, respectively. From the photoluminescence measurement of $ZnIn_2S_4$ single crystal thin film, we observed free excition $(E_X)$ typically observed only in high quality crystal and neutral donor bound exciton $(D^{o},X)$ having very strong peak intensity The full width at half maximum and binding energy of neutral donor bound excition were 9 meV and 26 meV, respectively, The activation energy of impurity measured by Haynes rule was 130 meV.

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Pretreatment of Diltiazem Ameliorates Endotoxin-Induced Acute Lung Injury by Suppression of Neutrophilic Oxidative Stress (내독소로 유도된 급성폐손상에서 Diltiazem 전처치가 호중구성 산화성 스트레스에 미치는 효과)

  • Jang, Yoo Suk;Lee, Young Man;Ahn, Wook Su;Lee, Sang Chae;Kim, Kyung Chan;Hyun, Dae Sung
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.4
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    • pp.437-450
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    • 2006
  • Background : Acute respiratory distress syndrome (ARDS) is characterized by severe inflammatory pulmonary edema of unknown pathogenesis. To investigate the pathogenesis of ARDS associated with neutrophilic oxidative stress, the role of phospholipase $A_2$ ($PLA_2$) was evaluated by the inhibition of calcium channel. Methods : In Sprague-Dawley rats, acute lung injury (ALI) was induced by the instillation of E.coli endotoxin (ETX) into the trachea. At the same time, diltiazem was given 60 min prior to tracheal instillation of ETX. Parameters of ALI such as lung and neutrophil $PLA_2$, lung myeloperoxidase (MPO), BAL neutrophils, protein, surfactant were measured. Production of free radicals from neutrophils was measured also. Morphological studies with light microscope and electron microscope were carried out and electron microscopic cytochemistry for detection of free radicals was performed also. Results : Diltiazem had decreased the ALI parameters effectively in ETX given rats and decreased the production of free radicals from neutrophils and lung tissues. Morphological studies denoted the protective effects of diltiazem. Conclusion : Diltiazem, a calcium channel blocker, was effective in amelioration of ALI by the suppression of neutrophilic oxidative stress mediated by $PLA_2$ activation.