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Characteristics of Metal-Phthalocyanine for Catalytic Combustion of Methanol (메탄올의 촉매연소에 대한 금속-프탈로시아닌의 특성)

  • Seo, Seong-Gyu;Yoon, Hyung-Sun;Lee, Sun-Won
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1809-1816
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    • 2000
  • The catalytic combustion of methanol as a model volatile organic compound(VOC) was been investigated over metal-phthalocyanine(PC) in a fixed bed flow reactor system. The catalytic activity of Co-PC pretreated with air and methanol mixture at $450^{\circ}C$ and 60 cc/min for 1 hr was very excellent. The order of catalytic activity on methanol combustion was summarized as follows: metal free-PC < Zn-PC < Fe-PC < Cu($\alpha$)-PC < Co-PC. By TG/DTA analysis, the tendency of thermal decomposition was increased as follows: metal free-PC < Zn-PC < Cu($\alpha$)-PC < Co-PC < Fe-PC. Under this pretreatment condition, the basic structures of Co-PC, Cu($\alpha$)-PC and Fe-PC were destroyed, and the new metal oxide such as $Co_3O_4$ from Co-PC was confirmed by EA and XRD analysis. But Zn-PC and metal free-PC were retained its basic structure under this pretreatment condition. On the combustion of methanol over Co-PC, HCHO and $HCOOCH_3$ were observed as an intermediate products in the high concentration of reactant or the short contact time(W/F).

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The Response Correction Function of TL Dosimeter for Shallow Dose Assessment in Tl-204 Beta Fields (Tl-204 베타선장에서의 피부선량평가를 위한 열형광선량계의 베타보정함수)

  • Lee, Sang-Yoon;Kim, Jang-Lyul;Seo, Kyung-Won
    • Nuclear Engineering and Technology
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    • v.26 no.3
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    • pp.381-388
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    • 1994
  • Recently, the American National Standards Institute (ANSI) had made some changes in the radiation sources specified from those in the original performance test criteria ANSI N13. 11-1983. In case or beta category, in addition to the high-energy $^{90}$ Sr/$^{90}$ Y beta source, the $^{204}$ Tl source was added because many workplaces have significant levels of lower energy betas. In this study, the performance or the Teledyne PB-3 personnel dosimetry system in the fields of $^{204}$ Tl and $^{90}$ Sr/ $^{90}$ Y beta was investigated using the PTB beta secondary standard sources. The new beta correction function of PB-3 personnel dosimetry system for $^{204}$ Tl beta was also developed in this response experiment. The results show that the Teledyne PB-3 personnel dosimetry system is very effective for $^{90}$ Sr/ $^{90}$ Y beta dose assessment. In case of $^{204}$ Tl beta radiation, however, the results of simple performance test indicated that the use of beta correction factor(=2.088) which was recommanded by manufacturer may result in unexpectable overestimation of delivered dose by about 60%, while the use of developed beta correction function could measure the delivered doses in errors of 15%.

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Endobronchial Brachytherapy for Malignant Airway Obstruction: Low Dose Rate Versus High Dose Rate (악성 종양에 의한 기도폐쇄시 내기관지 근접치료 : 저선량 치료 대 고선량 치료의 비교)

  • Cho, Young-Kap
    • Radiation Oncology Journal
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    • v.14 no.2
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    • pp.123-128
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    • 1996
  • Purpose : This is a retrospective study to compare the Palliation rates, survival rates and complications of low dose rate and high dose rate endobronchial brachytherapy in the management of malignant airway obstruction. Materials and methods : Forty three consecutive patients with malignant airway compromise from primary or metastatic lung tumors were treated with low dose rate(LDR) endobronchial Iridium-192 insertion(21 patients) between October 1988 and June 1992, and high dose rate(HDR) endobronchial brachytherapy(22 patients) between August 1992 and April 1994 with palliative aim Flexible fiberoptic bronchoscopy under fluoroscopic control was utilized in all 91 procedures. Twenty seven LDR Procedures delivered a dose of 5-7.5 Gy to a 1.0 cm radius respectively. Results : Subjective and objective responses to treatments were evaluated on follow-up examinations by clinical examination, chest x-rays and CT scan of the chest on some patients. Fifteen of 21 LDR patients and 19 of 22 HDR Patients showed subjective improvement in terms of better breathing and less Productive cough as well as complete disappearance of hemoptysis. Objective improvement on chest x-rays and CT scan of the chest had been demonstrated on 8 LDR Patients and 10 HDR patients. Conclusion : The technique of LDR and HDR endobronchial brachytherapy is simple and well tolerated procedure with minimal morbidity It Provides excellent palliation by keeping airway Patent in these short life-spanned patients.

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Phase identification and degree of orientation measurements far fine-grained rock forming minerals using micro-area X-ray diffractometer -$Al_{2}SiO_{5}$ Polymorphs- (미소부 X-선 회절분석기를 이용한 미립조암광물의 상동정 및 배향도 측정 -$Al_{2}SiO_{5}$ 3상다형-)

  • 박찬수;김형식
    • The Journal of the Petrological Society of Korea
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    • v.9 no.4
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    • pp.205-210
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    • 2000
  • Measurements of phase identification and degree of orientation for fine-grained (about 0.3 mm in diameter) minerals in rock samples performed by micro-area X-ray diffractometer.$Al_{2}SiO_{5}$ polymorphs (andalusite, kyanite and sillimanite) were chosen for the measurements and target minerals were existed on thin sections. Micro-area X-ray diffractometer is composed of 3(${\omega}\;{\chi}\;{\phi}$)-circle oscillating goniometer and position sensitive proportional counter (PSPC). $CuK_{\alpha}$ radiation was used as X-ray source and a pin hole ($50\;\mu\textrm{m}$$ in diameter) collimator was selected to focus radiation X-ray onto the target minerals. Phase identification and diffracted X-ray peak indexing were carried out by 3(${\omega}\;{\chi}\;{\phi}$)-circle oscillation measurement. Then, 2(${\omega}\;{\phi}$)-circle oscillation measurement was made for the purpose of searching the prevailing lattice plane of the minerals on thin section surface. Finally, for a selected peak by 2-circle oscillation measurement, X-ray pole figure measurement was executed for the purpose of check the degree of orientation of the single lattice direction and examine its pole distribution. As a result of 3-circle oscillation measurement, it was possible that phase identification among $Al_{2}SiO_{5}$ polymorphs. And from the results of 2-circle oscillation measurement and X-ray pole figure measurement, we recognized that poles of andalusite (122), kyanite (200) and sillimanite (310) lattice plances were well developed with direction normal to each mineral surface plane respectively. Therfore, the measurements used with micro-area X-ray diffractometer in this study will be a useful tool of phase identification and degree of orientation measurement for fine-grained rock forming minerals.

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Microbiological and Physiological Qualities of Electron-beam and Gamma-ray Irradiated Sprout Seeds(Radish, Red cabbage) during Germination (전자빔과 감마선 조사된 무순 및 적양배추 종자의 발아 중 미생물학적 및 생리적 품질특성)

  • Park, Ju-Hwan;Kim, Gui-Ran;Kwon, Joong-Ho
    • Food Science and Preservation
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    • v.16 no.2
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    • pp.186-191
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    • 2009
  • An electron beam or gamma-rays(0-5 kGy) were applied to two popular commercial sprout seeds, those of radish and red cabbage, and both physiological and microbiological qualities during germination were examined. Total bacterial counts of radish and red cabbage seeds were 5.02 and 2.86 log CFU/g, respectively, and were reduced by 2-3 logs after irradiation, but nonirradiated and irradiated samples showed similar microbial populations on day 5 after germination, although day 3 levels of irradiated samples were $23{\pm}2%$ lower. Coliforms were absent in both seed types. However, they were detected from the first day of germination, and rose to 4-5 log CFU/g on the fifth day. Coliforms were reduced by about 1-2 log CFU/g in 1 kGy-irradiated samples and were absent in the samples irradiated at 3 kGy. Irradiation at 1 and 3 kGy decreased germination by about 7% and 18%, respectively. Sprout yield and length were also significantly affected by irradiation, with no apparent difference between samples treated with the electron beam and gamma-rays.

Extraction and Biological Activities of Essential Oil from Thuja occidental Leaves (서양측백나무 잎으로부터 식물정유 추출 및 생리활성)

  • Seo, Weon-Taek;Yang, Jae-Kyung;Kang, Byung-Kuk;Park, Woo-Jin;Hong, Seong-Cheol;Kang, Young-Min;Jung, Hee-Young;Kim, Yong-Duck;Kang, Seung-Mi;Kim, Seon-Won;Choi, Myung-Suk
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.5
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    • pp.364-370
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    • 2003
  • Essential oil of Thuja occidental leaves was extracted by steam distillation method, and chemical composition of essential oil was analyzed by GC-MS. The essential oil was tested to antimicrorbiaI activity against 28 test microorganisms and antioxident assay through DPPH free radical scaveging test and insecticidal activity by mosquito insecticide assay. The major constituents in the essential oil of T. occidental were monoterpene as d-isothujone, ${\alpha}-thujone$, camphor, L-fenchone, and hornyl acetate. The essential oil have broad antimicrobiaI activity, which showed strong antimicrobiaI activity for Streptococcus pyogenes as bacteria, Alternaria alternata, Aspergillus niger, Aspergillus oryzae, Saccharomyces cerevisiae, and Streptococcus mutans as fungi. The essential oil also showed DPPH free radical scavenging ability at concentration of $36\;{\mu}{\ell}/m{\ell}$. In spraying and fumigation tests, the essential oil had strong insecticidal activity against mosquito.

The Use of Open Global Network System Interconnection in E-Trading (전자무역의 글로벌 네트워크 개방시스템 상호연결 활용에 관한 연구)

  • Jeong, Boon-Do;Yun, Bong-Ju
    • International Commerce and Information Review
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    • v.16 no.1
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    • pp.207-226
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    • 2014
  • A trade logistic informatization system under Open Systems Interconnection(OSI) includes a Port Management Information System, a Maritime Information System, and an Export and Import Batch Processing System. These have made a great contribution in the creation of more convenient and efficient management for the logistics industries in our country. However, this management is exposed to the technological problems of networks due to the explosive use in the sending and receiving of e-documents. For our country to grow as a center for port and logistic information, we should make the best use of the control systems using networks and further advance the export and import logistic systems. Therefore, this study aims to propose management systems for a composite network and an invasion detection system for efficient management of an e-trade network under OSI. Methods to rationalize the internal organizations such as coordination of organizations and human resources according to alloted network functions, commissions and arbitrary decisions, and reorganization of relevant regulations are not discussed here. This study looked at trade network under OSI from the aspect of practical business affairs and presented a basis for further interpretation.

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Fabrication and Performance of Microcolumnar CsI:Tl onto Silicon Photomultiplier (실리콘광증배관 기반의 미세기둥 구조 CsI:Tl 제작 및 평가)

  • Park, Chan-Jong;Kim, Ki-Dam;Joo, Koan-Sik
    • Journal of IKEEE
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    • v.20 no.4
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    • pp.337-343
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    • 2016
  • This study conducted the gamma ray spectroscopic analysis of the microcolumnar CsI:Tl deposited onto the SiPMs using thermal evaporation deposition. The SEM measured thickness of microcolumnar CsI:Tl and of its individual columns. From the SEM observation, the measured thickness of CsI:Tl were $450{\mu}m$ and $600{\mu}m$. The gamma ray spectroscopic properties of microcolumnar CsI:Tl, $450{\mu}m$ and $600{\mu}m$ thick deposited onto the SiPMs were analyzed using standard gamma ray sources $^{133}Ba$ and $^{137}Cs$. The spectroscopic analysis of microcolumnar CsI:Tl deposited onto the SiPMs included the measurements of response linearity over the $^{137}Cs$ gamma ray intensity; and gamma ray energy spectrum. Furthermore from the gamma ray spectrum measurement of $^{133}Ba$ and $^{137}Cs$, $450{\mu}m$ thick CsI:Tl showed good efficiency when measured with $^{133}Ba$ and $600{\mu}m$ thick CsI:Tl was highly efficient when measured with $^{137}Cs$.

Development of the Algorithm for On-line Dosimetry System for High Energy Radiation Treatment (고에너지 방사선치료용 on-line 선량측정시스템을 위한 알고리즘의 개발)

  • Wu, Hong-Hyun;Ha, Sung-Whan
    • Journal of Radiation Protection and Research
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    • v.22 no.3
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    • pp.207-218
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    • 1997
  • Purpose: The objective of this study is to develop an algorithm for estimation of tumor dose using measured transmission dose as a part of the development of on-line dosimetry system. Materials and Methods: Data of transmission dose were measured under various FS, Tp and PCD with a special water phantom for 6 MV and 10 MV X-ray. SCD (source-chamber distance) was set to 150 cm. Measurements were conducted with a 0.125 cc ion chamber. Results: Using measured data and regression analysis, two algorithms were developed for estimation of expected reading for measured data. Algorithm 1 consisted of the quadratic function of PCD and the tertiary function of AlP (area-perimeter ratio). Algorithm 2 consisted of the tertiary function of log(A/P)and the tertiary function of PCD. Algorithm 2 required less data set and was more accurate in comparing expected and observed dose. Conclusion: Using the algorithm developed, transmission dose can be estimated for any exposure condition, i.e. any given Tp, PCD and FS with high accuracy. To complete this algorithm, further developments are needed regarding the beam modifying device, the tissue inhomogeneity and the irregular body surface.

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Determination of Personnel Exposures in the Lower Energy Ranges of X-Ray by Photographic Dosimeter (저(低)에너지 X-선장(線場)에서 필름배지에 의한 개인피폭선량(個人被曝線量)의 결정(決定))

  • Ha, C.W.;Kim, J.R.;Suh, K.W.
    • Journal of Radiation Protection and Research
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    • v.11 no.1
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    • pp.57-64
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    • 1986
  • This paper described an improved technical method required for proper evaluation of personnel exposures by means of the photographic dosimeter developed by KAERI in lower gamma or X-ray energy regions, with which response of the dosimeter varies significantly. With calibration of the dosimeter in the energy range from 30 to 300 keV, the beam spectrum was carefully selected and specified it adequately. The absorber combinations and absorber thickness used to obtain the specified X-ray spectra from a constant potential X-ray machine were determined theoretically and also experimentally. A correlation between the density and exposure for the four separate energies, such as $49\;keV_{eff},\;154\;keV_{eff}\;250\;keV_{eff}\;and\;662\;keV$, is experimentally determined. As a result, it can be directly evaluated the exposure from the measured response of dosimeter.

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