동형 모더나이트 상에서 일산화탄소 산화반응에 대한 속도론

정명수,이창용,최고열,하백현 漢陽大學校 環境科學硏究所 1989 環境科學論文集 Vol.10 No.-

모더나이트에 동을 이온교환 및 담지시킨 후 환원·산화 처리를 하여 동의 상태를 변화시킨 촉매에 대해 일산화탄소 산화반응의 속도론적인 고찰을 행하였다. 이온교환 촉매나 담지촉매 모두 동의 상태와는 관계없이 일산화탄소에 관한 반응차수는 1차이고 산소에 관한 반응차수는 0차였다. 이온교환 촉매의 경우는 수소로 환원시켜 동이 금속상태로 존재할때와 이를 재산화시켜 산화동 상태로 존재할때는 활성화에너지가 각각 16.4 및 20.3으로 비교적 큰 값을 나타냈으나 동의 담지촉매의 경우는 동이 금속일 때나 산화물 상태 모두 12∼13kcal/mole로 비슷한 값을 나타냈으며 이온교환 촉매보다 상당히 감소함을 알 수 있었다. 이와 같은 결과는 이온교환 촉매의 경우는 동이 제올라이트내부에 대부분 존재하는 반면, 담지촉매의 경우는 제올라이트 결정 표면에 존재하기 때문에 활성을 증가시키는 것으로 생각된다. Kinetics of oxidation of carbon monoxide over copper mordenite was carried out at the temperature range between 373K-443K in the micro-catalytic reactor. The experimental results indicated that the reaction order, with respect to carbon monoxide and oxygen was first and zero order respectively, regardless of the valence states such as copper metal, copper ion and copper oxide on the mordenite. The activation energy for metal-copper mordenite which is obtained by the ion-exchange revealed 20kcal/mol. But if this was reoxidized under the oxygen it decreased to 16.6kcal/mol. The activation energy of metal-copper mordenite which was obtained by impregnation and its reoxidized one under the oxygen were 12.2kcal/mol and 13.3kcal/mol respectively.

고분자 전해질형 연료전지에서 Hot Pressing 조건의 영향

이태희,이승재,조원일,노용우,고영태,최경환 한국화학공학회 1996 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.34 No.1

고분자 전해질형 연료전지에서 고분자막/전극 어셈블리를 hot pressing 조건을 달리하여 제조하고 그 성능을 반응면적 5㎠인 단위전지에서 측정하였다. 전지의 성능은 고분자막과 전극간의 접합이 가능한 온도 범위에서 hot pressing온도가 낮을수록, hat Pressing 압력이 높을수록 향상되었다. 즉, 고분자 전해질형 연료전지의 성능은 고분자 전해질 내의 수분 함량 증가, 고분자막/전극간 접촉저항 감소 및 얇은 고분자막을 사용한 전해질의 이온저항 감소 등으로 향상시킬 수 있었다. For a proton exchange membrane fuel cell, membrane and electrode assemblies were fabricated by different hot pressing conditions and those performances were observed in a unit cell having 5 ㎠ active electrode area. The cell performance increased with lower hot pressing temperature in the range of temperature having intimate contact between membrane and electrodes and with higher hot pressing pressure. Namely, the performance of proton exchange membrane fuel cell could be raised with higher water content in the membrane, with lower contact resistance between membrane and electrodes and with lower ion resistance of the electrolyte using thinner membrane.

Weighing similarity against functionality to evaluate dung beetle species candidates for taxon substitution using an individual-based model

Jung-Wook Kho,Jung-Wook Kho,Joo-Young Kim,Do-Hun Gook,Hyunjoong Kim,Soowan Kim,Doo-Hyung Lee 한국응용곤충학회 2023 한국응용곤충학회 학술대회논문집 Vol.2023 No.04

BROWN GAS INCINERATOR FOR WASTE DESTRUCTION AND ENVIRONMENTAL POLLUTION COMPLIANCE

Kho Boon Kie,Ashwani K. Gupta 국제과학영재학회 2012 APEC Youth Scientist Journal Vol.4 No.-

All municipal wastes consists large amounts of water (as much as 60% by mass) which hinders the performance of waste incinerators. Excess water can easily be separated out from the municipal solid wastes using centrifuges. The waste water can be reformed to Brown gas (di-atomic and mon-atomic hydrogen and oxygen) using an electrolyzers. At the instant that the water splits, the hydrogen and oxygen are in their mon-atomic state (H and O). Brown gas in the form of hydrogen and oxygen production form waste water is useful from waste waters and all kinds of solid wastes. Dehydrated waste can be easily combusted in an incinerator. Waste is an unavoidable by-product of most human activity. Economic development and rising living standards, including the Asian and Pacific Region have led to increased quantity and complexity of generated waste, whilst industrial diversification and the provision of expanded health-care facilities have added substantial quantities of industrial hazardous waste and biomedical waste into the waste stream with potentially severe environmental and human health consequences. Technologies available remove the large and diverse amounts of wastes generated include incineration, ocean dumping, lagooning, sanitary landfill, direct combustion, pyrolysis, gasification and more. However, available information reveals that incineration.is widely used with reasonable good success to manage the large amounts of wastes generated from low moisture content wastes. Today most incinerators are stoker incinerator which produces dioxins in low temperatures regions of the incinerator as well as other criteria pollutants emission. . High temperature (1600C) zones in the incinerator assist in melting the glass and metal in the waste to mitigate dioxin formation and release of heavy metals in to the environment. Low energy density and high moisture content in the waste require the use of auxiliary fuel to maintain high temperatures in the incinerator. Separating out the water from waste and reforming water to Brown gas and burning low moisture solid wastes in incinerator helps environmental benign means of wastes management. In this paper, different technologies are described that form key elements of overall waste management system, including the brown gas production from the water collected from solid wastes that can be used in the incinerator to further increase the incinerator temperature.

Fermentation of MR-387A and H, Novel Aminopeptidase M Inhibitors by Streptomyces sp. SL-387 : Carbon and Nitrogen Catabolite Repression of Inhibitor Formation

Kho, Yung-Hee,Chung, Myung-Chul,Chun, Hyo-Kon,Lee, Choong-Hwan,Lee, Ho-Jae,Kim, Su-Il The Korean Society for Microbiology and Biotechnol 1995 Journal of microbiology and biotechnology Vol.5 No.3

The effect of carbon and nitrogen sources on the production of novel aminopeptidase M inhibitors MR-387A and B by Streptomyces sp. SL-387 has been studied. High D-glucose and ammonia concentrations (5$\%$/> and 1$\%$/>, respectively) exerted a negative influence on the inhibitor formation. The suppressive effect of glucose on the inhibitor formation is probably caused by an effect of medium pH rather than that of cyclic AMP. To establish the optimum conditions for inhibitor overproduction, various nitrogen sources and ammonium ion-trapping agents were examined. The use of ammonia slow-releasing nitrogen sources such as soybean meal and fish meal, or ammonium ion-trapping agents such as kaoline, celite, and natural zeolite achieved the enhancement of inhibitor production. These results also indicate that inhibitor formation is affected by ammonium ion repression.

<i>Gastrodia elata</i> Ameliorates High-Fructose Diet-Induced Lipid Metabolism and Endothelial Dysfunction

Kho, Min Chul,Lee, Yun Jung,Cha, Jeong Dan,Choi, Kyung Min,Kang, Dae Gill,Lee, Ho Sub Hindawi Publishing Corporation 2014 Evidence-based Complementary and Alternative Medic Vol.2014 No.-

<P>Overconsumption of fructose results in dyslipidemia, hypertension, and impaired glucose tolerance, which have documented correlation with metabolic syndrome. <I>Gastrodia elata</I>, a widely used traditional herbal medicine, was reported with anti-inflammatory and antidiabetes activities. Thus, this study examined whether ethanol extract of <I>Gastrodia elata</I> Blume (EGB) attenuate lipid metabolism and endothelial dysfunction in a high-fructose (HF) diet animal model. Rats were fed the 65% HF diet with/without EGB 100 mg/kg/day for 8 weeks. Treatment with EGB significantly suppressed the increments of epididymal fat weight, blood pressure, plasma triglyceride, total cholesterol levels, and oral glucose tolerance, respectively. In addition, EGB markedly prevented increase of adipocyte size and hepatic accumulation of triglycerides. EGB ameliorated endothelial dysfunction by downregulation of endothelin-1 (ET-1) and adhesion molecules in the aorta. Moreover, EGB significantly recovered the impairment of vasorelaxation to acetylcholine and levels of endothelial nitric oxide synthase (eNOS) expression and induced markedly upregulation of phosphorylation AMP-activated protein kinase (AMPK)<I><I>α</I></I> in the liver, muscle, and fat. These results indicate that EGB ameliorates dyslipidemia, hypertension, and insulin resistance as well as impaired vascular endothelial function in HF diet rats. Taken together, EGB may be a beneficial therapeutic approach for metabolic syndrome.</P>

Identification and intracellular localization of carbonic anhydrase I in gills, heart, muscle, and intestine of rainbow trout, Oncorhynchus mykiss

Kho, Kang Hee,Kim, Jung Woo,Kim, Soo Cheol,Choi, Myeong Rak,Han, Kyeong Ho,Lee, Won Kyo,Choi, Kap Seong The Korean Society for Applied Biological Chemistr 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.5

Carbonic anhydrases (CAs) play a key role in physiological functions such as pH homeostasis, calcification, photosynthesis, and ionic regulations. Among CA isozymes, CA I is a specific marker for the cytoplasm or apical cell membranes of colonic epithelial cells, and it is related to enterocyte proliferation in mammals. The major aim of the present study was to investigate the regional, cellular, and subcellular localization of CA I in a fish, rainbow trout, Oncorhynchus mykiss. The CA I was identified in the gills, heart, and intestine of the rainbow trout. CA I protein detected in the tissues of the rainbow trout was similar to a CA III with a molecular weight of 29 kDa. Immunohistochemical results demonstrated that CA I was localized in the various cells of gills, heart, muscle, and intestine of the rainbow trout.

The Reclamation of Body in Beloved

Kho, Younghee(고영희) 새한영어영문학회 2016 새한영어영문학 Vol.58 No.4

This paper explores the ways in which reclaiming body is central for former African American slaves to achieve their freedom from the haunting past of slavery in Toni Morrison’s Beloved. The subject of motherhood under slavery Morrison chose, in which mother-child relationship deteriorates into the possessive one of slavery, helps us see how serious and ongoing the problem of slavery is. When slave catchers find Sethe and her children, she attempts to kill all of them as if their bodies were owned by her, a consequence of her unconscious internalization of the slave owner’s logic. Morrison reveals the problem of such internalization through Beloved’s claim of her mother’s body. When she returns in the form of a young woman, Sethe becomes almost enslaved by Beloved and her insatiable demands. Their relationship soon degenerates into violence, testifying that they have not yet escaped out of their slaved past, a past thriving and waiting to overwhelm African American lives like “jungle” at any time. The real escape from the past comes when they acknowledge the necessary separation of their bodies. Only with such acknowledgement, Sethe is able to overcome the trauma of the past experiences and to recover from the fragmented body parts to the whole self.

Erratum : Expression of 17β-Hydroxysteroid Dehydrogenease in Testis of the Ascidian Ciona intestinalis

Kho, Kang Hee,Inaba, Kazuo Korean Society for Molecular and Cellular Biology 2005 Molecules and cells Vol.19 No.2

A report of three unrecorded Ovulid species (Gastropoda, Heterodonta) from Korea

Kho, Dong-Bum,Lee, Jun-Sang,Min, Duk-Ki The Malacological Society of Korea 2015 The Korean Journal of Malacology Vol.31 No.1

Three Ovulid species collected from Jeju Island were identified as Habuprionovolva aenigma (Azuma & Cate, 1971), Habuprionovolva basilia (Cate, 1978) and Diminovula kosugei (Cate, 1973). This is the first record from the Korean waters, providing a description of the species with illustration for the shell morphology.