Methy Tosylate의 가용매분해반응에 관한 硏究

朴炳瑞,金永基 順天大學校 1985 論文集 Vol.4 No.1

pxksdhf-아세토니트릴 및 메탄올-아세톤 혼합용매계에서 MeOTs의 가용매 분해반응을 50℃와 60℃에서 속도론적으로 연구하였다. 메탄올-아세토니틀릴 혼합용매계에서는 메탄올 함량이 90%(V/V%)인 용매조성에서 최대 반응속도 현상이 나타났다. 확장된 Grunwald-Winstein 관계식을 이용하여 본 혼합용매의 친핵도 N값을 구하였으며, 용매의 친핵도는 용매조성 변화에 따라 달라짐을 알 수 있었다. Kinetic studies for the solvoluysis of methyl tosylate have been carried out in methanol-acetonitrile and methanolacetone mixtures at 50. O and 60. O ℃. In this reaction system maximum rate constant was shown at 90% (V/V%) methanol acetonitrile mixture. Solvent nucleophilicity N values were calculated from kinetic data using the extended G runwald-W instein equation It is shown that the values vary according as the solvent composition changes.

연료가스 생산을 위한 폐타이어와 하수슬러지의 수증기가스화반응

송병호 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

Waste tire scrap and dried sewage sludge have been gasified with steam in a thermobalance at temperature of 550-850℃ and steam pressure of 25-101.3 kPa. The volatile in waste tire particles was rapidly evolved in two minutes, and the residual char that is about 30 wt% of particle was reacted with steam to produce product gas containing hydrogen. Three gas-solid reaction models in literature have been used to describe the reaction behavior. The results indicate that steam gasification of both the waste tire and sludge is mainly controlled by chemical reaction. The rate of reaction is proportional to the partial pressure of steam. Among the tested gas-solid reaction models, the modified volumetric reaction model was found to be mostly appropriate. The apparent activation energy for steam gasification of waste tire, coal and sludge were found to be 39.1, 99.3, 156.5 kJ/mol respectively and the apparent reaction rates were determined.

Pleurotus ostreatus의 액체 종균 생산에 관한 연구

강태수,천병익 江原大學校 産業技術硏究所 1988 産業技術硏究 Vol.8 No.-

For the improvement of productivity of Pleurotus ostreatus, the production of liquid spawn was studied. The highest liquid spawn production was obtained after shaking culture for 4 days in the culture medium containing 5%(W/V) wheat flour, 0.2%(W/V) yeast extract, 0.1%(W/V)KNO3 0.05%(W/V)MgSO47H2O, 0.05%(W/V)KH2PO4. The optimum pH and temperature was 7.0 and 30℃. The period required to complete the mycelial growth after spawning were 28, 22, 10 and 9 days, respectively, when the 2%(V/V) of solid spawn and 2%(V/V), 5%(V/V) and 10%(V/V) of liquid spawn were inoculated. The days required from spawning to fruiting bodies were 38, 34, 28 and 27 days.

광섬유 격자 다중화 스트레인 센서 시스템

이용욱,정재훈,정승환,이병호,김남식 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.2

광섬유 센서는 구조물에 대한 비파괴적인 측정이 가능하고, 전자파에 의한 간섭이 발생하지 않으므로, 전자파 장애의 영향을 무시할 수 있는 장점이 있다. 또한, 구조물 건조시 콘크리트 같은 대상체에 광섬유를 내장시킬 경우에는 검사시 대상체를 파괴시키지 않고서도 대상체의 손상여부와 역학적 거동을 측정 및 해석할 수 있는 비파괴 검사 기술이다. 특히 광섬유 브래그 격자 센서는 그러한 대상체에 대한 비파괴 검사를 수행하는데 가장 적합한 센서이다. 광섬유 브래그 격자 센서는 그러한 대상체에 대한 비파괴 검사를 수행하는데 가장 적합한 센서이다. 광섬유 브래그 격자는 특정파장의 빛을 반사 또는 제거시키는 특성을 지니고 있으며, 스트레인 같은 물리량이 광섬유 브래그 격자에 가해지면, 반사되는 빛의 중심파장이 이동하여 이를 통해 물리량을 측정할 수 있다. 정ㆍ동적 스트레인을 측정할 수 있는 광섬유 브래그 격자 센서는 건축물이나 토목구조물 등의 안전 진단(health monitoring)을 위해 사용되고 있으며, 최근에는 도로나 교량과 같은 토목 구조물로의 응용에 있어서 필수적인 동적 스트레인의 측정에 대해 그 관심이 집중되고 있다. 본 연구에서는 패브리=페로(Fabry-Perot) 필터를 이용하여 다중점에서 동적 스트레인을 측정할 수 있는 센서 시스템을 제작하였으며, 제작된 센서 시스템을 모의 구조물(외팔보)에 적용하여 모의 구조물에 가해지는 정적, 동적 스트레인을 측정하였다. 측정 결과는 기존의 전기적 센서와 유사하였다. An optical fiber sensor is capable of nondestructive measurement of a structure and it has an advantage of the immunity to electromagnetic interference because light is not affected by electromagnetic wave. In addition, if optical fibers are buried in an object like a concrete, this sensor can analyze defects and physical status of the object without disassembling it. Especially, the fiber Bragg grating sensor is a promising optical fiber sensor capable of nondestructive test of such an object. A fiber Bragg grating has the characteristics of reflecting or blocking light of a specific wavelength. If we apply physical quantity like strain to the fiber Bragg grating, the center wavelength of the reflected light is shifted and then we can find the physical quantity applied to the fiber Bragg grating by measuring the center wavelength shift of the reflected light. The fiber Bragg grating sensor capable of static and dynamic strain measurement is being used in health-monitoring of buildings, structures, etc. Recently increasing is interest in dynamic strain measurement inevitable to the civil structures such as roads and bridges. In this study we implemented the optical fiber sensor system which can measure dynamic strain at multiple points using Fabry-Perot wavelength demodulation. And we measured the static and dynamic strain using this sensor system with a test structure(cantilever). Measurement results were similar to those obtained with the conventional electrical measurement methods.

알레르기성 비염 환자에서 절지동물성 특이항원의 양성율 및 항원간 일치율

황규윤,남해선,박준수,권준택,백병준,김장묵,오천환,조성란 순천향의학연구소 2000 Journal of Soonchunhyang Medical Science Vol.6 No.2

The current study was designed to evaluate the positive rates of arthropod allergens by Korean inhalant panel of MAST-CLA in patients with allergic rhinitis. One hundred sixty patients, diagnosed to allergic rhinitis in an Out Patient Center of Soonchunhyang University Chunan Hopsital during Aug 1998 to July 2000, were studied. 1. The overall positive rate among 35 specific allergens was 59.4% (95 patients). 2. The arthropod related allergen accounted for 82.1% (78 patients) of the positive rate. 3. Each positive rate of Dermatophagoides farinae (Df), Dermatophagoides pteronyssinus (Dp), house dust (Hd), and cockroach mix (Cm) was 45.0% (72 patients), 43.1% (69 patients), 28.1% (45 patients), and 8.8% (14 patients), respectively. 4.Significant agreement between arthropod allergens was observer (P < 0.05). 5. The obseved agreement between Df and Dp was 95.6%, showing most significant Kappa index (Kappa = 0.911, P < 0.001). There results suggested that although MAST-CLA is a useful measure of identifying specific allergens, the specificity of two mite allergen relatively low, implying because of common allergen between mites in Korean panel of MAST-CLA. Our data also supported that arthropod is the major cause of allergen in patients with allergic rhinitis, however, the MAST-CLA should be modified in order to exclude common allergen of mite and to include more specific mite allergen.

Effects of Socio-Demographic Characteristics and Peer Relations on the Emotional, Behavioral, and Comorbid Disorder Symptoms in Low-SES Children

( Byoun Gduk Sohn ) 대한가정학회 2010 International Journal of Human Ecology Vol.11 No.1

The current study examined the effects of socio-demographic characteristics and peer relations on the emotional, behavioral, and comorbid disorder symptoms among low-low-SES children, using the Young Lives Survey: an International Study of Childhood Poverty: Round 1, 2002. Participants were 1,000 8-year-old children (502 boys and 498 girls) from low-low-SES families. Data were analyzed using ANOVA, t-tests, post hoc test (Scheffe`s method), correlations, and multiple logistic regression analyses according to the analysis strategy. There was a moderate correlation between selected socio-demographic variables and emotional/behavioral disorder symptoms, and the caregiver`s marital status, child`s health compared to others, child`s work status corresponded to significant differences in their emotional/behavior levels. Regarding the logistic regression analysis, in addition to the effects of socio-demographic variables reflecting the characteristics of less-developed countries, marital status, child`s working status, and conflicts with peers proved to be detrimental to emotional, behavioral, or comorbid disorder symptoms in low-SES children, who have been lack quality parenting, social resources, and child human rights. Results indicated the need to develop health care services that would address those problems and appropriate intervention and prevention programs targeting children in low-income families. Moreover, careful assessment and intervention for child`s health status, child`s working status and peer relationship problems are suggested as possible strategies for helping children at risk of exhibiting further problematic behaviors.

Characterization of Pulse Reverses Electroforming on Hard Gold Coating

Byoun, Young-Min,Noh, Young-Tai,Kim, Young-Geun,Ma, Seung-Hwan,Kim, Gwan-Hoon American Scientific Publishers 2018 Journal of nanoscience and nanotechnology Vol.18 No.3

<P>Effect of pulse reverse current (PRC) method on brass coatings electroplated from gold solution was investigated by various plating parameters such as plating duration, the anodic duty cycle, the anodic current density and the cathodic current density. The reversed current results in a significant change in the morphology of electrodeposits, improvement of the overall current efficiency and reduction of deposit porosity. With longer pulses, hemispherical surface features are generated, while larger grains result from shorter pulse widths. The porosity of the plated samples is found to decrease compared with results at the same time-average plating rate obtained from DC or Pulse plating. A major impediment to reducing gold later thickness is the corrosion of the underlying substrate, which is affected by the porosity of the gold layer. Both the morphology and the hydrogen evolution reaction have significant impact on porosity. PRC plating affect hydrogen gold and may oxidize hydrogen produced during the cathodic portion of the waveform. Whether the dissolution of gold and oxidation of hydrogen occur depends on the type of plating bath and the plating conditions adapted. In reversed pulse plating, the amount of excess near-surface cyanide is changed after the cathodic current is applied, and the oxidation of gold under these conditions has not been fully addressed. The effects of the current density, pulse-reverse ratio and brightener concentration of the electroplating process were investigated and optimized for suitable performance.</P>

Comparison of Endovascular Treatments of Ruptured Dissecting Aneurysms of the Intracranial Internal Carotid Artery and Vertebral Artery with a Review of the Literature

Byoun, Hyoung Soo,Yi, Hyeong Joong,Choi, Kyu Sun,Chun, Hyoung Joon,Ko, Yong,Bak, Koang Hum The Korean Neurosurgical Society 2016 Journal of Korean neurosurgical society Vol.59 No.5

Objective : Subarachnoid hemorrhage (SAH) caused by rupture of an internal carotid artery (ICA) or vertebral artery (VA) dissecting aneuryesm is rare. Various treatment strategies have been used for ruptured intracranial dissections. The purpose of this study is to compare the clinical and angiographic characteristics and outcomes of endovascular treatment for ruptured dissecting aneurysms of the intracranial ICA and VA. Methods : The authors retrospectively reviewed a series of patients with SAH caused by ruptured intracranial ICA and VA dissecting aneurysms from March 2009 to April 2014. The relevant demographic and angiographic data were collected, categorized and analyzed with respect to the outcome. Results : Fifteen patients were identified (6 ICAs and 9 VAs). The percentage of patients showing unfavorable initial clinical condition and a history of hypertension was higher in the VA group. The initial aneurysm detection rate and the percentage of fusiform aneurysms were higher in the VA group. In the ICA group, all patients were treated with double stent-assisted coiling, and showed favorable outcomes. In the VA group, 2 patients were treated with double stent-assisted coiling and 7 with endovascular trapping. Two patients died and 1 patient developed severe disability. Conclusion : Clinically, grave initial clinical condition and hypertension were more frequent in the VA group. Angiographically, bleb-like aneurysms were more frequent in the ICA group and fusiform aneurysms were more frequent in the VA group. Endovascular treatment of these aneurysms is feasible and the result is acceptable in most instances.

A Classification Scheme for Information and Telecommunications Technologies

Byoun, Bogyun,Bae, Moonsik,Youn, Cheong,Mirza, Misbah 충남대학교 기초과학연구소 1996 忠南科學硏究誌 Vol.23 No.2

Classification helps us assign knowledge and relationships to unknown objects and to structure domains of systematic inquiry. This is particularly applicable to the emerging new fields which are coming about as a result of the convergence of information and telecommunications fields. This paper looks at different classifications schemes which can be applied to these fields and suggests a suitable scheme with examples of its application to the above mentioned fields. The classification scheme presented is multi-dimensional. These dimensions are structural, commercial. and functional. They take into account aspects necessary in the classifications of such technologies. The scheme also incorporates some necessary aspects of software design process, namely, coupling and cohesion.

Risk Assessment of Human Exposure to Methidathion during Harvest of Cucumber in Green House

Byoun Ji-Youn,Choi Hoon,Moon Joon-Kwan,Park Hee-Won,Liu Kwang-Hyeon,Ihm Yang-Bin,Park Byeoung-Soo,Kim Jeong-Han Korean Society of ToxicologyKorea Environmental Mu 2005 Toxicological Research Vol.21 No.4

Farmers are generally expressed to pesticides through mixing loding, application activity and harvesting of crop after application of pesticides. The present work investigated the exposure and risk of furathiocarb to workers when harvesting of cucumber was carried out in green house after application of furathiocarb EC. Glove was used for the hand exposure assessment, socks for foot and dermal patches for the other parts of body. Personal air monitor equipped with a XAD-2 resin was used for the respiratory exposure assessment. During the harvest of cucumber in green house, the initial rate of potential dermal exposure (Day 1) for methidathion was 1.3 mg/hr. The major exposure parts were hand $(78\~83\%),\;thigh\;(5\~7\%)$ and arms $(6\~9\%)$ during 3 days' harvest. No exposure was detected from the respiratory monitoring. For risk assessment, the potential dermal exposure (PDE), the absorbable quantity of exposure (AQE) and the margin of safety (MOS) and margin of exposure (MOE) were calculated. In risk assessment of harvester exposure for 7days, all MOS was > 1 and MOE was > 100 indicating that possibility of risk was little.