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Investigation on CO Adsorption and Catalytic Oxidation of Commercial Impregnated Activated Carbons (상용 첨착활성탄의 일산화탄소 흡착성능 및 촉매산화반응 연구)

  • Ko, Sangwon;Kim, Dae Han;Kim, Young Dok;Park, Duckshin;Jeong, Wootae;Lee, Duck Hee;Lee, Jae-Young;Kwon, Soon-Bark
    • Applied Chemistry for Engineering
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    • v.24 no.5
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    • pp.513-517
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    • 2013
  • We investigated the properties of impregnated activated carbons, a commercial adsorbent for the individual protection equipment, and examined CO adsorption and oxidation to $CO_2$. The surface area, pore volume and pore size were measured for four commercial samples using Brunauer-Emmett-Teller/Barrett-Joyner-Halenda (BET/BJH), and atomic compositions of the sample surface were analyzed based on SEM/EDS and XPS. Impregnated activated carbons containing Mn and Cu for fire showed the catalytic CO oxidation to $CO_2$ with a high catalytic activity (up to 99% $CO_2$ yield), followed by the CO adsorption at an initial reaction time. On the other hand, C: for chemical biologial and radiological (CBR) samples, not including Mn, showed a lower CO conversion to $CO_2$ (up to 60% yield) compared to that of fire samples. It was also found that a heat-treated activated carbon has a higher removal capacity both for CO and $CO_2$ at room temperature than that of untreated carbon, which was probably due to the impurity removal in pores resulted in a detection-delay about 30 min.

Comparison of Physiological Variables by Age Group in Drinking Men (음주남성의 나이대별 생리학적 변수들의 비교)

  • Hyun, Kyung-Yae
    • Journal of Life Science
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    • v.19 no.10
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    • pp.1374-1381
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    • 2009
  • This study was designed to investigate the differences of physiological variables by age group in alcohol-consuming men. The thirty year old-age group had the lowest waist-hip ratio (WHR), right and left cardio-ankle vascular index (R-CAVI and L-CAVI), right and left ankle-brachial index (R-ABI and L-ABI), amylase, high sensitivity C-reactive protein (hs-CRP), and creatine phosphokinase (CPK) levels, and the highest body weight (BW), interleukin-6 (IL-6), right and left intraocular pressure (R-IP and L-IP), hematocrit (Hct), hemoglobin (Hb), erythrocyte, red blood cells distribution width (RDW), alanine aminotransferase (ALT), total cholesterol (TCH), triglyceride (TG), and ferritin levels. The forty year old-age group was the highest in hs CRp and CPK levels, but the lowest in ferritin level. The fifty year old-age group possessed the highest WHR, diastolic blood pressure (DBP), R- and L-ABI, eosinophil, and amylase levels. The sixty year old-age group had the highest R- and L-CAVI, mean corpuscular volume (MCV), ALP, $\gamma$-glutamyltranspeptidase ($\gamma$-GTP), rheumatoid factor (RF), $\alpha$-fetoprotein (AFP) and prostate specific antigen (PSA) levels and the lowest BW, DBP, R-IP, L-IP, Hct, Hb, leukocyte, platelet, RDW, eosinophil, monocyte, ALT, amylase, TG, and CPK levels. These findings indicate that there may be differences of physiological variables depending on age group in alcohol-consuming men. Further studies should be focused on the physiological differences between alcohol-consuming men and women.

The syudy of reaction kinetics in the thermophilic aerobic digestion process of piggery wastewater (축산폐수의 고온호기성 소화공정에서의 반응동력학 연구)

  • Kim, Yong-Kwan;Kim, Seok-Won;Kim, Baek-Jae
    • Proceedings of KOSOMES biannual meeting
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    • 2007.11a
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    • pp.97-102
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    • 2007
  • The piggery wastewater is the major source of the water pollution problem in the rural area. The treatment alternatives for piggery wastewater are limited by the characteristics of both high organic and nitrogen(N) content. In order to investigate an efficient N removal system, the thermophilic aerobic digestion process was examined. The experiment was investigated organic and nitrogen removal efficiency at various HRTs and air supply volume. The results of semi-continuous experiment indicated that a higher removal of the soluble portion of COD was achieved with the longer HRTs. However, the inert portion of COD in piggery wastewater was not much changed by thermophilic aerobic digestion. In addition, with the higher HRT of 3 days, up to 79% of NH4-N removal efficiency was achieved. Lower the HRTs, a decrease of NH4-N removal was founds. The gas samples from the lab reactor were analyzed along with the N content in influent and effluent. The N2O formation in our system indicates a novel aerobic deammonification process occurred during the thermophilic aerobic digestion. Both N02 and N03 were not presented in the effluent of thermophilic aerobic digester. With the HRT of 3 days, 36.4% of influent N(or 57.5% removal N) was aerobically converted to N2O gas. The ammonium conversion to N2O gas significantly decrease to 4.5% at low HRT of .05 day..

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Corrosion Prediction of a Cement Mortar-Grouted Rockbolt by Measuring Its Chloride Diffusion Coefficient (시멘트 모르타르계 록볼트 충전재의 염화물 확산계수 측정을 통한 록볼트 부식 예측)

  • Bae, Gyu-Jin;Chang, Soo-Ho;Kim, Dong-Gyou;Park, Hae-Geun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.8 no.3
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    • pp.259-271
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    • 2006
  • This paper aims to predict the corrosion of a fully cement-grouted rockbolt induced by chloride diffusion in a cement mortar grout. From the viewpoint of the long-term durability, a rockbolt may be deteriorated by chemical components, such as sulphate and chloride, in groundwater. Especially, the steel rod of a rockbolt is corroded mainly by chloride. The rockbolt corrosion results in the volume expansion of a rod and then the cracking of a cement grout. In this study, the chloride diffusion coefficient of a cement mortar grout was used to evaluate the possibility of rockbolt corrosion by chloride, and to predict the long-term durability of a rockbolt. The electric acceleration test method was adopted to measure the chloride diffusion coefficient. In addition, a simple pullout testing system was newly proposed to measure the pullout capacity of a rockbolt more easily in a laboratory condition. From the experiments, it was showed that the chloride could diffuse in the cement grout more easily than in ordinary concrete materials. As a result, it was considered that a rockbolt might be easily corroded in a short term by the diffusion of chemical components with high concentration, although it was fully grouted.

A study on the action mechanism of internal pressures in straight-cone steel cooling tower under two-way coupling between wind and rain

  • Ke, S.T.;Du, L.Y.;Ge, Y.J.;Yang, Q.;Wang, H.;Tamura, Y.
    • Wind and Structures
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    • v.27 no.1
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    • pp.11-27
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    • 2018
  • The straight-cone steel cooling tower is a novel type of structure, which has a distinct aerodynamic distribution on the internal surface of the tower cylinder compared with conventional hyperbolic concrete cooling towers. Especially in the extreme weather conditions of strong wind and heavy rain, heavy rain also has a direct impact on aerodynamic force on the internal surface and changes the turbulence effect of pulsating wind, but existing studies mainly focus on the impact effect brought by wind-driven rain to structure surface. In addition, for the indirect air cooled cooling tower, different additional ventilation rate of shutters produces a considerable interference to air movement inside the tower and also to the action mechanism of loads. To solve the problem, a straight-cone steel cooling towerstanding 189 m high and currently being constructed is taken as the research object in this study. The algorithm for two-way coupling between wind and rain is adopted. Simulation of wind field and raindrops is performed with continuous phase and discrete phase models, respectively, under the general principles of computational fluid dynamics (CFD). Firstly, the rule of influence of 9 combinations of wind sped and rainfall intensity on flow field mechanism, the volume of wind-driven rain, additional action force of raindrops and equivalent internal pressure coefficient of the tower cylinder is analyzed. On this basis, the internal pressures of the cooling tower under the most unfavorable working condition are compared between four ventilation rates of shutters (0%, 15%, 30% and 100%). The results show that the 3D effect of equivalent internal pressure coefficient is the most significant when considering two-way coupling between wind and rain. Additional load imposed by raindrops on the internal surface of the tower accounts for an extremely small proportion of total wind load, the maximum being only 0.245%. This occurs under the combination of 20 m/s wind velocity and 200 mm/h rainfall intensity. Ventilation rate of shutters not only changes the air movement inside the tower, but also affects the accumulated amount and distribution of raindrops on the internal surface.

Postpartum Reproductive Management Based on the Routine Farm Records of a Dairy Herd: Relationship between the Metabolic Parameters and Postpartum Ovarian Activity

  • Takagi, Mitsuhiro;Hirai, Toshiya;Moriyama, Naoki;Ohtani, Masayuki;Miyamoto, Akio;Wijayagunawardane, Missaka P.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.6
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    • pp.787-794
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    • 2005
  • The aim of this study was 1) to confirm the practical efficiency of a routine milk P4 monitoring system for postpartum reproductive management of a dairy herd, and 2) to evaluate the relationship between the blood metabolic profiles, milk quality and body weight of individual cows in the farm records, which may reflect the postpartum nutritional condition, and the time of postpartum resumption of ovarian activity of dairy cows. A total of 116 Holstein cows was used in the present study. First, during the period of Experiment 1, postpartum reproductive management based on weekly measured milk P4 concentration from individual cows was conducted. Compared with the reproductive records of the past two years without P4 monitoring, although the day from calving to first AI did not change, both the number of AI until pregnant (with P4; 1.9 times vs. without P4; 2.9 times) and the days open (with P4; 95.1 days vs. without P4; 135.8 days and 133.8 days) were significantly decreased. In Experiment 2, the measurement of blood constituents such as albumin, blood urea nitrogen, packed cell volume, ammonia, glucose, total cholesterol, non-esterified, AST and $\gamma$-GTP was performed on the blood samples taken once approximately 14 days postpartum, to monitor both health and nutritional conditions. The milk constituent parameters, such as milk protein (MP), milk fat (MF), SNF and lactose, collected from the monthly progeny test of individual cows, were used to monitor the postpartum nutritional status. Furthermore, the data obtained from the routine measurements of body weight were used to calculate the rate of peripartum body weight loss. The resumption day of the postpartum estrous cycle was assumed from the milk P4 profiles of individual cows. There was no clear relationship between each parameter from blood examination and those from resumption time. However, the cows had low values of MP, and SNF, which significantly affected the resumption of the postpartum estrous cycle. Similarly, a higher rate of body weight loss indicated a significant delay (more than 1 month) in the resumption of the postpartum estrous cycle, compared with the groups that had a medium or lower rate of body weight loss. The results of the present study demonstrated that the implementation of routine milk P4 monitoring-based postpartum reproductive management, together with milk quality parameters and routine BW data available in field conditions may be utilized as a practical approach for increasing the postpartum reproductive efficiency of a high yielding dairy herd.

Kinetics of the Reaction of Benzyl Chlorides with Pyridine in Methanol Solvent under High Pressure (고압하의 메탄올 용매내에서 염화벤질류와 피리딘과의 반응에 대한 반응속도론적 연구)

  • Oh Cheun Kwon;Young Cheul Kim;Jin Burm Kyong;Kee Joon Choi
    • Journal of the Korean Chemical Society
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    • v.31 no.5
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    • pp.413-418
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    • 1987
  • Rates of the reaction for p-nitro benzyl chloride, benzyl chloride and p-methyl benzyl chloride with pyridine in methanol solvent have been measured by an electric conductivity method at 40$^{\circ}$C and 50$^{\circ}$C under various pressures (1∼2000bar). Pseudo first-order rate constants and second-order rate constants were determined. Rates of these reactions were increased in the order p-NO$_2$ < p-H < p-CH$_3$ and increased with temperature, pressure and concentration of pyridine. From those rate constants, the activation parameters were evaluated. The activation volume and the activation compressibility coefficient are both negative values, but the activation enthalpy is positive and the activation entropy is large negative value. From the evaluation of the ground state and transition state which was resulted from substituents and pressure, it was found that this reaction proceeds through S$_N$2 reaction, and S$_N$2 fashion is slightly disappeared as pressure increases.

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Freshwater Fish Fauna and Distribution in Kojedo, Korea (거제도의 담수어류상과 분포상의 특징)

  • Son, Yeong-Mok;Song, Ho-Bok
    • Korean Journal of Ichthyology
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    • v.10 no.1
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    • pp.87-97
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    • 1998
  • The freshwater fish fauna and distribution were investigated in Kojedo from 1982 to 1997. The collected fishes were classified into twenty four species of ten families. Dominant species was Zacco temmincki (relative abundance: 18.1%) and subdominant species was Rhinogobius brunneus (16.4%). Also Iksookimia longicorpus (12.3%), Oryzias latipes (7.5%), Chaenogobius urotaenia (7.5%) and Carassius auratus (6.9%) were numerous. The endemic species of Korea were six species (25.0%) and endangered species were C. splendidus, S. microdorsalis and C. kawamebari. In this study, species diversity index was high at Yoncho stream, dominance index at Aju and Oaepo stream and evenness index at Oaepo stream in community structure. There was a tendency of fish distribution in Kojedo that more longer the stream and more larger the water volume were, there were more species and more individual numbers. It was considered that the dominance of upper and middle reach dwelling fishes resulted in the dominance of Aa type stream mainly. Liobagrus mediadiposalis and L. mediadiposalis ssp. 1 showed different distribution pattern in Kojedo : that is, the former inhabited in east-northern part but the latter in south-western part separately. And the importance of this distribution pattern was discussed in relation to paleogeography.

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A Study for Applying for Crowdsourcing Technology in ITS (크라우드 소싱의 ITS 적용 방안)

  • Park, Bum-Jin;Moon, Byung-Sup;Byeon, Jang-Seon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.2
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    • pp.48-56
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    • 2012
  • One kind of crowdsourcing techniques which allow drivers to collect and provide traffic information using smartphones and applications is being introduced to ITS system as well. The introduction of crowdsourcing techniques requires changes in the existing ITS based on Insourcing which provide traffic information generated by detectors through VMS. ITS Information have had two problems, one is the high cost and the other is an interrupted service. Experts expect crowdsourcing technique which is created SNS, will overcome problems of ITS. But, there are not many examples and research results. Crowdsourcing technique was utilized in Jeju ATMS project to install ITS on the coastal round roads around Jeju since ITS to install point detectors turned out to be non-economic method in case of the coastal round roads with low traffic volume. However, there existed links in which traffic information cannot be generated as there were no smartphone users (crowds) even in the cost-effective crowdsourcing techniques, which indicates the fact that the crowdsourcing method is suitable for urban roads with many smartphone users, but not for local minor roads. On the contrary, insourcing-based ITS is considered to be non-economic method in applying to all roads in the city, but it can be effectively utilized in the local minor roads. Accordingly, Inter-sourcing based ITS operating system in which insourcing is connected with crowdsourcing was suggested in this study.

A Study on the Elution Mechanism of Ni(II)-Isonitrosoethylacetoacetate Imine Chelates by Reversed Phase High Performance Liquid Chromatography (역상 액체 크로마토그래피에 의한 Ni(II)-Isonitrosoethylacetoacetate Imine 유도체 킬레이트의 용리 메카니즘에 관한 연구)

  • Kim In-Whan;Choi Gang-Yeol;Lee Man-Ho;Kang Chang-Hee;Lee, Won
    • Journal of the Korean Chemical Society
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    • v.36 no.5
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    • pp.697-708
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    • 1992
  • Liquid Chromatographic behavior of Ni(II) in Isonitrosoethylacetoacetate Imine(IEAA-NR), Ni(IEAA-NH)(IEAA-NR)(R = H, CH_3, C-2H_5, n-C_4H_9, C_6H_5-CH_2) chelates were investigated by reversed-phase HPLC on Micropak MCH-5 column using methanol/water as mobile phase. The optimum conditions for the separation of Ni(IEAA-NH)(IEAA-NR) chelates were examined with respect to the effect of the flow rate, sample solvent, mobile phase strength and column temperature. It was fo$und that metal chelates were properly eluted in an acceptable range of capacity factor value(0{\le}logk'{\le}1). The dependence of the logarithm of capacity factor (k') on the volume fraction of water in the binary mobile phase as well as on the liquid-liquid extraction distribution ratio (Dc) in methanol-water/n-alkane extraction system showed the good linearties, and the dependence of the logarithm of capacity factor (k') on the column temperature and on the enthalpy exhibited the good linearties, and the compensation temperature ({\beta}) from the slope was 773.47{\circ}K. It was suggested that the retention of metal chelates was largely affected by the hydrophobic effect.

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