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A Study on the chemical analysis of synthesized Li-AGICs with changes of intercalant contents (Intercalant 함량 변화에 따라 합성된 Li-AGICs의 화학적 분석에 관한 연구)

  • Oh, Won-Chun;Shim, Sang-Kyun
    • Analytical Science and Technology
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    • v.10 no.3
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    • pp.209-215
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    • 1997
  • Li-AGICs as a anode of secondary battery were synthesized by high-pressure method as a function of the Li-contents. The characteristics of these prepared compounds were determined from the studies with X-ray diffraction method, UV/VIS spectrophotometric and differential scanning calorimeter(DSC) analysis. From the results of X-ray diffraction, it was found that the lower stage intercalation compounds were formed with increase of Li-contents. The mixed stages in these compounds were also observed. In the case of the $Li_{30wt%}$-AGIC, the compounds in the stage 1 structure were formed predominantly, but the structure of only pure stage 1 for structural defect of artificial graphite is not observed. According to UV/VIS spectrophotometric analysis, $Li_{30wt%}$-AGIC shows distinguishable energy state spectrum with the position of $R(%)_{min}$ values, but the characteristic spectra of almost all Li-AGICs are not observed. The enthalpy and entropy changes of the compounds can be obtained from the differential scanning calorimetric analysis results. From the results, it was found that exothermic and endothermic reactions of Li-AGICs are related to thermal stability of lithium between artificial graphite layers.

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A Study of Monitoring and Operation for PEM Water Electrolysis and PEM Fuel Cell Through the Convergence of IoT in Smart Energy Campus Microgrid (스마트에너지캠퍼스 마이크로그리드에서 사물인터넷 융합 PEM 전기분해와 PEM 연료전지 모니터링 및 운영 연구)

  • Chang, Hui Il;Thapa, Prakash
    • Journal of the Korea Convergence Society
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    • v.7 no.6
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    • pp.13-21
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    • 2016
  • In this paper we are trying to explain the effect of temperature on polymer membrane exchange water electrolysis (PEMWE) and polymer membrane exchange fuel cell (PEMFC) simultaneously. A comprehensive studying approach is proposed and applied to a 50Watt PEM fuel cell system in the laboratory. The monitoring process is carried out through wireless LoRa node and gateway network concept. In this experiment, temperature sensor measure the temperature level of electrolyzer, fuel cell stack and $H_2$ storage tank and transmitted the measured value of data to the management control unit (MCU) through the individual node and gateway of each PEMWE and PEMFC. In MCU we can monitor the temperature and its effect on the performance of the fuel cell system and control it to keep the lower heating value to increase the efficiency of the fuel cell system. And we also proposed a mathematical model and operation algorithm for PEMWE and PEMFC. In this model, PEMWE gives higher efficiency at lower heating level where as PEMFC gives higher efficiency at higher heating value. In order to increase the performance of the fuel cell system, we are going to monitor, communicate and control the temperature and pressure of PEMWE and PEMFC by installing these systems in a building of university which is located in the southern part of Korea.

A Study on Algorithm of the Integrated Communication System in Radio Station (무선국의 통합 시스템에 대한 알고리즘의 연구)

  • 조학현;최조천;김기문
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.2 no.4
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    • pp.545-551
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    • 1998
  • The Radio communication by existing SSB, VHF, etc. in a coast station and a base station for military affairs is still used to a very important the device of information delivery or transmitting and receiving by the remote controller to using to the exclusive cable for a equipment established at a long distance. When a number of consumer to connected and operated by a number of transceiver is essential for a circuit controller of ICS, in KOREA, is devoted by import to considerable quantity because of to be delayed development of this field. This Paper has been realized to optimal algorithm and designing of a circuit connection controller by multi-processor to pre-stage for the development of ICS. The H/W is composed able to remote control to circuit connector with the several slave processor and a processor for master, and this has taken possible through without any obstacle to communication circuits of a control signal by FSK system. The S/W make possible monitoring for communication condition of other circuits by means of a serial communication system by the multi-processing. This paper has been studied for connecting to a circuits wished to rapidly and precisely by the full application to a interrupt technique. A technique to control by remote to a number of transceiver is a way increasing to application for a frequency resource of the limited MF/SF, VHF and the existing radio communication technique. According to, this paper will achieve to be the reduction of energy & equipment and multiplicity of information delivery in the general communication and disposal to rapid and exact for the important communication as distress, urgency and safety on the sea.

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Different Sources and Levels of Copper Supplementation on Performance and Nutrient Utilization of Castrated Black Bengal (Capra hircus) Kids Diet

  • Mondal, M.K.;Biswas, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1067-1075
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    • 2007
  • Twenty eight 3-4 month old castrated Black Bengal kids (Capra hircus) were used to determine the effects of source and level of dietary copper (Cu) concentration on their performance and nutrient utilization. Cu was supplemented (0, 10, 20 and 30 mg/kg diet DM) as copper sulfate ($CuSO_4$, $5H_2O$) or copper proteinate (Cu-P). Kids were fed a basal diet containing maize (19.5%), soybean (17.0%), deoiled rice bran (56.5%), molasses (4.0%), di-calcium phosphate and salt (1.0% each) and mineral and vitamin mixture (0.5% each) supplements at 3.5% of body weight to meet NRC (1981) requirements for protein, energy, macro minerals and micro minerals, excluding Cu. The basal diet contained 5.7 mg Cu/kg, 122.5 mg Fe/kg, 110 mg Zn/kg, 0.26 mg Mo/kg and 0.32% S. $CuSO_4$ or Cu-P was added to the basal diet at the rate of 10, 20 and 30 mg/kg. Kids were housed in a well ventilated shed with facilities for individual feeding in aluminum plated metabolic cages. Blood samples were collected from the jugular vein on d 0, 30, 60 and 90 to determine hemoglobin (Hb), packed cell volume (PCV), total erythrocyte count (TEC), total leukocyte count (TLC) and serum enzymes (alkaline phosphatase, alanine transferase and aspertate transferase). A metabolism trial of 6 days duration was conducted after 90 days of experimental feeding. Statistical analysis revealed that source and level of Cu supplementation improved live weight gain (p<0.04) and average daily gain (p<0.01). No significant contribution of source and level of Cu to alter serum serum enzymes was evident. Goats fed Cu-P tended to have higher Hb, PCV and TEC than with $CuSO_4$ supplementation. Cu-P increased digestibility of ether extract (EE, p<0.02) and crude fiber (p<0.05) and showed an increasing trend (p<0.09) for digested crude protein (CP) and crude fiber (CF). Supplemental dose of Cu linearly improved (p<0.02) digestibilities of dry matter (DM), organic matter (OM), EE and nitrogen free extract (NFE). Though the absorption of nitrogen (N) was not affected (p>0.10) by both source and dose of Cu, N retention was affected (p<0.04) and there was a significant $Source{\times}Dose$ interaction (p<0.05). Final body weight (BW) was not influenced (p>0.10) by the source of Cu but increasing dose of Cu increased (p<0.04) the BW of kids. TDN intake (g/kg $W^{0.75}$) was higher (p<0.05) with the increased dose of Cu and there was a significant $Source{\times}Dose$ interaction. It was concluded that supplementation of Cu from different sources and varying dose level in a concentrate based diet may improve performance, nutrient utilization and plane of nutrition in castrated Black Bengal kids. The effects on performance and nutrient utilization are more pronounced with Cu-P than $CuSO_4$ supplementation. Higher dose of Cu showed better result than lower dose.

Deinococcus rubrus sp. nov., a Bacterium Isolated from Antarctic Coastal Sea Water

  • Srinivasan, Sathiyaraj;Lim, Sangyong;Lim, Jae-Hyun;Jung, Hee-Young;Kim, Myung Kyum
    • Journal of Microbiology and Biotechnology
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    • v.27 no.3
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    • pp.535-541
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    • 2017
  • Two Gram-staining-negative, red-pinkish, coccus-shaped, non-motile, and aerobic bacterial strains, designated $Ant21^T$ and Ant22, were isolated from the Antarctic coastal sea water. Strains $Ant21^T$ and Ant22 showed UVC and gamma radiation resistance. Phylogenetic analyses based on 16S rRNA gene sequences determined that these strains belong to the genus Deinococcus. Through the analyses of the 16S rRNA gene sequences, strains $Ant21^T$ and Ant22 were found to have 97.7% and 97.8% similarity to Deinococcus marmoris DSM $12784^T$ and 97.0% and 97.2% similarity to Deinococcus saxicola AA-$1444^T$, respectively. The sequence similarity with the type strains of other Deinococcus species was less than 96.9% for both strains. Strains $Ant21^T$ and Ant22 shared relatively high 16S rRNA gene sequence similarity (99.3%) and had a closely related DNA reassociation value of $84{\pm}0.5%$. Meanwhile, they showed a low level of DNA-DNA hybridization (<30%) with other closely related species of the genus Deinococcus. The two strains also showed typical chemotaxonomic features for the genus Deinococcus, in terms of the major polar lipid (phosphoglycolipid) and the major fatty acids ($C_{16:0}$, $C_{16:1}$ ${\omega}6c/{\omega}7c$, $iso-C_{17:0}$, and $iso-C_{15:0}$). They grew at temperatures between $4^{\circ}C$ and $30^{\circ}C$ and at pH values of 6.0-8.0. Based on the physiological characteristics, the 16S rRNA gene sequence analysis results, and the low DNA-DNA reassociation level with Deionococcus marmoris, strains $Ant21^T$ ($=KEMB\;9004-167^T$ $=JCM\;31436^T$) and Ant22 (KEMB 9004-168 =JCM 31437) represent novel species belonging to the genus Deinococcus, for which the name Deinococcus rubrus is proposed.

Characteristics Evaluation on Welding Metal Zones Welded with Inconel 625 Filler Metal to Cast Steel for Piston Crown Material

  • Jeong, Jae-Hyun;Moon, Kyung-Man;Lee, Sung-Yul;Lee, Myeong-Hoon;Baek, Tae-Sil
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.5
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    • pp.542-547
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    • 2015
  • Since the oil price has been significantly jumped for several years, a heavy oil of low quality has been mainly used in the diesel engine of the merchant ship. Thus, a combustion chamber of the engine has been often exposed to severely corrosive environment more and more because temperature of the exhaust gas of the combustion chamber has been getting higher and higher with increasing of using the heavy oil of low quality. As a result, wear and corrosion of the engine parts such as exhaust valve, piston crown and cylinder head surrounded with combustion chamber are more serious compared to the other parts of the engine. Therefore, an optimum repair welding for these engine parts is very important to prolong their lifetime in a economical point of view. In this study, Inconel 625 filler metal were welded with GTAW method in the cast steel which would be generally used with piston crown material. And the corrosion properties of weld metal, heat affected and base metal zones were investigated using electrochemical methods such as measurement of corrosion potential, anodic polarization curves, cyclic voltammogram and impedance etc. in 35% $H_2SO_4$ solution. The weld metal and base metal zones exhibited the highest and lowest values of hardness respectively. Furthermore, the corrosion current density of the weld metal zone revealed the lowest value, having the highest value of hardness. The corrosive products with red color and local corrosion like as a pitting corrosion were considerably observed at the base metal zone, while these morphologies were not wholly observed in the weld metal zone. In particular, the polarization characteristics such as impedance, polarization curve and cyclic voltammogran associated with corrosion resistance property were well in good agreement with each other. Consequently, it is suggested that the mechanical and corrosion characteristics of the piston crown can be predominantly improved by repair welding method using the Inconel 625 electrode.

EFFECTS OF DIETARY FULL-FAT SOYBEAN LEVELS ON GROWTH PERFORMANCE AND FEED UTILIZATION AND PHOSPHORUS EXCRETION OF CARP (Cyprinus carpio)

  • Kim, J.D.;Kim, K.S.;Song, J.S.;Woo, Y.B.;Jeong, K.S.;Won, T.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.6
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    • pp.587-594
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    • 1995
  • In order to estimate the nutritive value of roasted full-fat soybean (FFS) in carp diet, growth performance and excretion of protein and phosphorus were examined using carps having mean body weight of 111 g. Growth trial was conducted for 4 weeks using the fishes fed 5 diets (Control, $F_{24}S_{13}$, $F_{16}S_{27}$, $F_8S_{40}$ and $F_0S_{56}$) containing 32%, 24%, 16%, 8% and 0% of fish meal (F) and 0%, 13%, 27%, 40% and 56% of full-fat soybean, respectively. A total of 800 fishes were allotted randomly by groups of 40 to 5 treatments with 4 replicates per treatment. Fishes were fed to station eight times daily. Feeding trial was conducted for 4 weeks. As dietary FFS increased from 0% to 56%, weight gain of fish decreased from 91 g to 39 g and feed conversion ratio increased from 1.06 to 1.95. Protein efficiency ratio (PER) was highest (2.35) in control group which had the highest protein intake, while PER significantly decreased with decrease in protein intake as dietary FFS level increased. Although dietary protein and energy levels were maintained constant, protein excretion per kg weight gain varied from 273 g to 579 g for the groups control and $F_0S_{56}$, respectively. However, the value for control group was not significantly different to those for the groups $F_{24}S_{13}$ and $F_{16}S_{27}$. On the other hand, the highest protein retention efficiency was found in group fed the diet $F_{24}S_{13}$. Fish fed the diet $F_8S_{40}$ excreted the lowest phosphorus (P) based on kg weight gain showing the highest P retention efficiency of 62%. P excretion per kg feed intake was in the range of 5 g to 10 g for the groups $F_8S_{40}$ and $F_{24}S_{13}$, respectively. The present results indicated that as dietary FFS level increased, growth performance and feed utilization decreased while excretion of protein and phosphorus increased. Therefore, it was concluded that more than 25% substitution by FFS for fish meal could exert negative effects on growth and feed utilization of carp.

Electrochemical Characteristics of Nanotubular Ti-25Nb-xZr Ternary Alloys for Dental Implant Materials

  • Byeon, In-Seop;Park, Seon-Young;Choe, Han-Cheol
    • Journal of Korean Dental Science
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    • v.10 no.1
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    • pp.10-21
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    • 2017
  • Purpose: The purpose of this study was to investigate the electrochemical characteristics of nanotubular Ti-25Nb-xZr ternary alloys for dental implant materials. Materials and Methods: Ti-25Nb-xZr alloys with different Zr contents (0, 3, 7, and 15 wt.%) were manufactured using commercially pure titanium (CP-Ti), niobium (Nb), and zirconium (Zr) (99.95 wt.% purity). The alloys were prepared by arc melting in argon (Ar) atmosphere. The Ti-25Nb-xZr alloys were homogenized in Ar atmosphere at $1,000^{\circ}C$ for 12 hours followed by quenching into ice water. The microstructure of the Ti-25Nb-xZr alloys was examined by a field emission scanning electron microscope. The phases in the alloys were identified by an X-ray diffractometer. The chemical composition of the nanotube-formed surfaces was determined by energy-dispersive X-ray spectroscopy. Self-organized $TiO_2$ was prepared by electrochemical oxidation of the samples in a $1.0M\;H_3PO_4+0.8wt.%$ NaF electrolyte. The anodization potential was 30 V and time was 1 hour by DC supplier. Surface wettability was evaluated for both the metallographically polished and nanotube-formed surfaces using a contact-angle goniometer. The corrosion properties of the specimens were investigated using a 0.9 wt.% aqueous solution of NaCl at $36^{\circ}C{\pm}5^{\circ}C$ using a potentiodynamic polarization test. Result: Needle-like structure of Ti-25Nb-xZr alloys was transform to equiaxed structure as Zr content increased. Nanotube formed on Ti-25Nb-xZr alloys show two sizes of nanotube structure. The diameters of the large tubes decreased and small tubes increased as Zr content increased. The lower contact angles for nanotube formed Ti-25NbxZr alloys surfaces showed compare to non-nanotube formed surface. The corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface showed longer the passive regions compared to non-treatment surface. Conclusion: It is confirmed that corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface has longer passive region compared to without treatment surface.

Forsythia suspensa Extract Has the Potential to Substitute Antibiotic in Broiler Chicken

  • Han, X.;Piao, X.S.;Zhang, H.Y.;Li, P.F.;Yi, J.Q.;Zhang, Q.;Li, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.569-576
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    • 2012
  • Two experiments were conducted to investigate the potential for Forsythia suspensa extract (FSE) to substitute for antibiotic in broiler chicken. First, a well-diffusion assay procedure and a 2-fold dilution method were used to determine the bacteriostatic activity of FSE on Escherichia coli K88, staphylococcus aureus, and salmonella was assayed. An inhibitory effect of FSE was observed on the growth of these bacteria. This effect seems to be dose depended, which disappeared after 25.00, 12.50, 1.56 mg/ml. Second, a 42-d trial with 252 broiler chickens (d 1, $38.7{\pm}1.1$ g BW) was conducted to evaluate the effect of dietary supplementation of FSE in broiler chicken. The feeding program consisted of a starter diet from d 1 to 21 and a finisher diet from d 22 to 42. Dietary treatments included were: i) NC: negative control fed a corn-soybean meal based diet; ii) PC: positive control group fed based diet with chlortetracycline; and iii) FC: a test group fed with 100 mg FSE/kg diet. In this study growth performance did not differ among treatments during the starter period. However, dietary supplemental chlortetracycline and FSE increased (p<0.05) average daily gain (ADG), average daily feed intake (ADFI) compared with NC during the finisher and overall phase. Apparent digestibility of calcium on d 21, digestibility of energy and calcium on d 42 of FC was greater (p<0.05) than NC. Moreover, cecal Escherichia coli counts for birds from FC were lower (p<0.05) than NC. Dietary FSE supplementation also improved (p<0.05) villus height and villus height to crypt depth ratios in both duodenum and ileum and decreased (p<0.05) crypt depth in the duodenum. Duodenum villus height and villus height to crypt depth ratio in both duodenum and ileum from the FC group were also greater (p<0.05). Serum growth hormone and IGF-1 were not influenced by different treatments. Apparently, FSE has the potential to substitute for antibiotic in broiler chicken.

Effects of Milk Replacer and Ambient Temperature on Growth Performance of 14-Day-Old Early-Weaned Pigs

  • Heo, K.N.;Odle, J.;Oliver, W.;Kim, J.H.;Han, In K.;Jones, E.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.6
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    • pp.908-913
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    • 1999
  • This experiment was conducted in three trials to evaluate optimal ambient temperature for a novel milk replacer feeding system designed for early-weaned pigs, compared to commercial dry diets fed within a conventional hot nursery. A total of 165 PIC genotype pigs were weaned at $13.89{\pm}0.7$ days of age and allotted to one of two dietary treatments in three trials based on weight and litter origin. Each trial consisted of pigs fed dry diets (DD) and pigs fed milk replacer (MR) which was offered in one of 3 different ambient temperatures. Pigs fed milk replacer were housed in a specialized nursery building in which one half of each pen contained an enclosed hover that was thermostatically maintained at $32^{\circ}C$ while the exterior ambient temperature (where milk was fed) was set at either 17 (trial 1), 24 (trial 2) or $32^{\circ}C$ (trial 3). Pigs fed dry diets with the conventional nursery were maintained at $30^{\circ}C$ for each trial. From d 21 to d 49, all pigs were fed DD within a standardized hot nursery environment. During the first week (d 14-21), pigs fed MR showed increased ADG from 214% to 228% over control pigs fed DD (p<0.001), regardless of ambient temperature. As ambient temperature was increased from 17 to 24 to $32^{\circ}C$, ADG of MR-fed pigs was increased by 214%, 220% and 228% over those of pigs fed DD, respectively. ADFIs of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were increased by 108%, 139% and 164% from d 14 to d 21, respectively. Fed efficiency (G/F) of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were 199%, 162% and 139% of those of pigs fed DD, respectively. As ambient temperature increased, diarrhea scores showed a slight tendency to increase. The advantage of MR feeding was greater when the ambient temperature was higher, but G/F was impaired with increased ambient temperature. We conclude that ambient temperature within the specialized nursery influenced behavior, MR feed intake, and probably piglet energy expenditure. There were no differences between MR-fed and DD-fed pigs for ADG, ADFI and G/F in the subsequent growth period (d 21 to d 49, p>0.05). Maximal advantage of MR feeding was obtained at the intermediate ($24^{\circ}C$) ambient temperature during the overall period (p<0.05). Results from this experiment indicate that a milk replacer feeding system utilized in the early postweaning period can maximize pig growth performance, and that ADG, ADFI and G/F were affected by different ambient temperatures within MR-fed pigs. The high or low temperatures could not support the maximal growth of pigs fed MR.