Fabrication of ex situ processed MgB₂ wires using nano carbon doped powder

Lee, C.M.,Park, J.H.,Hwang, S.M.,Lim, J.H.,Joo, J.,Kang, W.N.,Kim, C.J. North-Holland 2009 Physica. C, Superconductivity Vol.469 No.15

We fabricated ex situ MgB<SUB>2</SUB> wires using C-doped MgB<SUB>2</SUB> powder as a precursor in order to improve the core density of the wires and their C doping content. The C-doped powder was prepared with Mg, B, and nano carbon (NC) powders by the in situ technique and then MgB<SUB>2-x</SUB>C<SUB>x</SUB> (x=0, 0.01, and 0.03) wires were fabricated by the ex situ technique using the powder-in-tube method. The phase formation, lattice change, and microstructure were characterized and correlated with the T<SUB>c</SUB> and J<SUB>c</SUB> variations. We observed that the ex situ wire had a higher core density than the in situ wire, however its morphology consisted of agglomerated particles, indicating that sintering and grain growth did not occur completely, even though the sintering was conducted at high temperature (1000<SUP>o</SUP>C). As the C content increased, T<SUB>c</SUB> decreased, while the decrease of J<SUB>c</SUB> with increasing magnetic field became smaller. The J<SUB>c</SUB> of MgB<SUB>1.97</SUB>C<SUB>0.03</SUB> wire made by the ex situ technique was 3.34kA/cm<SUP>2</SUP> at 6.6T and 5K which is comparable to that of the in situ wire (4.81kA/cm<SUP>2</SUP> at 6.6T and 5K).

Chlortetracycline 과 비닐포장처리에 의한 토육의 상온저장시험

이용빈,송계원,고준수 한국축산학회 1965 한국축산학회지 Vol.7 No.1

The shelf-life of cony meat was studied out in this experiment. After the rabbit dressed out, the meat was treated with 10 p.p.m. Chlortetracycline (C.T.C.) solution and packed with polyethylene. The samples were taken from the muscle of the rump and the round. We allotted eight treatments: That is, two temperature levels (5℃ and 20℃) that have two treatments: Control and C.T.C.-Treated. And each treatment of each temperature levels has two treatments, Control and Packed with Polyethylene. The items investigated are the change of the number of microorganisms, pH, and methylene blue reducing time. The results are as follows: 1. Effectively, C.T.C. suppressed the increasing of microorganisms of cony meat during the storage. And there was highly significant difference at 1.0% level in the C.T.C.-Treated meats on the Ist day of storage. The number of microorganism reached 10^8 per gram in 20℃-Control by the 2nd day of storage and 10^8 per gram by the 7th day of storage. 2. The increasing of yeasts was apparent in 20℃-C.T.C.-Treated on the 5th and 6th day of storage. And on the 7th day of storage, molds were also found. 3. Polyethylene packing was effective (significant at 5.0%) on the 2nd, 3rd, 4th, and 5th day of storage in 5℃-Control, and on the 2nd, 3rd day of storage in 20℃-C.T.C.-Treated. 4. The pH of cony meat during storage was lower in 20℃-C.T.C.-Treated by the 4th day of storage than in 5℃-Control, but after 5th day of storage, the pH of meat. was increased rapidly. 5. The C.T.C. treatment has a more strong effect upon the change of pH of cony meat than the polyethylene packing throughout the storage. And the effect of the temperature was greater than that of C.T.C.-Treatment. 6. C.T.C.-Treatment has shorten methylene blue reducing time than control (significant at 1.0%). And the methylene blue reducing time of 20℃-C.T.C.-Treated was similart to that of 5℃-Control all throughout the experiment period. 7. Polyethylene packing has an effect upon the methylene blue reducing time on the 3rd, 4th day of storage (significant at 5.0%). In the testing of L.S.D., there was no significant differences throughout the period.

소 c-KIT Receptor 유전자의 다형성에 관한 연구

장요순,김태헌,윤두학,박응우,이혜원,이학교,정일정 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

소의 흰 반점 관련 후보유전자로 c-KIT receptor 유전자를 선정하여, c-KIT receptor 유전자내의 변이를 탐색하고 변이가 흰반점 표현형과 연관성이 있는지를 분석하였다. 한우, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin 및 Simmental 등 8개 품종의 DNA 시료를 사용하여 c-KIT receptor 유전자의 intron 6번 영역에서 다형성을 조사하고 분석하였다. c-KIT receptor 유전자의 intron 6번 영역에서는 4개의 염기치환이 발견되어, MspⅠ, BsrBⅠ 및 NdeⅠ 제한효소를 이용하여 PCR-RFLP 분석을 실시하였다. Intron 6번을 포함하는 영역의 PCR 산물 크기는 2,440 bp 이었다. MspⅠ다형성은 PCR-RFLP 분석 결과 3개의 대립유전자가 존재하였으며, 한우품종에서는 3개의 대립유전자 모두가 발견되었고, CC 형태이 유전자형을 제외한 5개의 유전자형 (AA, AB, AC, BC 및 BB)을 확인하였다. Angus, Brown Swiss, Hereford, Holstein 및 Simmental 품종에서는 A 대립유전자만을 갖는 것으로 조사되었고, 한우는 44%만 AA 유전자형을 나타내었다. BsrBⅠ 다형성은 2개의 대립유전자로서 3개의 유전자형이 나타나는 것을 확인하였으며, Charolais 및 Hereford 품종이 다른 소 품종에 비하여 A 대립유전자의 빈도가 높게 나타났다. NdeⅠ 다형성을 분석한 결과 Brown Swiss 품종에서는 NdeⅠ에 의해 절단되는 형태인 A 대립유전자만 관찰되었으며, Holstein 품종은 92%, Simmental 품종은 72%가 절단되는 형태를 나타내어, 모색이 흰색을 띠는 소 품종에서 절단되는 형태가 많았다. 소 c-KIT receptor 유전자의 intron 6번 영역에서 확인된 4개의 염기치환은 품종에 따라 다른 빈도를 보였으나, 이들 염기치환과 흰 반점과의 연관성에 대한 증거는 발견하지 못하였다. 그러므로 소의 흰 반점과 c-KIT receptor 유전자 내의 변이와의 관련성은 다른 영역에 대한 추가적인 분석과, 이미 보고된 다른 모색관련 유전자의 다형성과의 연관성 분석 등과 같은 연구가 필요한 것으로 판단된다. We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental. When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by Msp Ⅰ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

주성분 분석을 이용한 거세한우의 체형분류에 관한 연구

하동우,김현철,김병우,이문연,이종헌,신철교,도창희,이정규 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

1997년부터 2001년까지 (사)한국종축개량협회의 전국한우능력평가대회에 출품된 642두의 거세한우의 도축 전까지 4회에 걸쳐 주요 10개 부위의 체형 측정치를 조사하여 주성분 분석을 이용하여 체형을 분류하였으며, 각 체형 측정치의 주성분 지수와 도체 형질과의 상관관계를 분석하였으며, 그 결과를 요약하면 다음과 같다. 1. 1차, 2차, 3차 및 4차 체형 측정치의 principal component(이하 P.C) 1의 분산은 각각 7.610, 8.297, 7.269 및 5.736로서 전체분산 중 76.0%, 83.0%, 72.7% 및 57.4%를 나타낼 수 있었고, P.C 1, P.C 2, P.C 3의 합은 전체분산 중 각각 86.69%, 90.49%, 84.62% 및 77.26%를 나타났다. 2. 각 차수별 체형 측정치의 P.C 1의 모든 계수가 양(+)이어서 일반적으로 좋은 체구의 크기를 나타내었으며, 체구의 크기에 가장 크게 영향을 미치는 형질은 흉심(0.328∼0.339)과 요각폭(0.325∼0.341)이였다. 또한 P.C 2, P.C 3 및 P.C 4는 각 차수별로 다양하게 나타났다. 3. 1차, 2차, 3차 및 4차 체형 측정치의 주성분 지수들과 도체형질간의 상관계수 추정에서 대부분의 분산을 차지하는 P.C 1은 도체중(0.539∼0.755), 일당증체량(0.256∼0.564), 등지방두께(0.227∼0.280) 및 배최장근단면적(0.187∼0.344)간에 정(+)의 상관을 보였으며, 육량지수(-0.246∼-0.110)와는 부(-)의 상관을 보였고, 근내지방도(0.066∼0.099)와는 대부분 유의적인 상관을 보이지 않거나 낮은 상관을 보였고, P.C 2, P.C 3 및 P.C 4는 주성분 지수들의 값에 따라 도체형질과 다양한 상관관계를 보였다. 단일 체형형질과 도체형질간의 상관 그리고 P.C 1의 주성분 지수와 도체형질과의 상관간에는 큰 차이가 없었다. Data were consisted of the ten body measurements (withers height, rump height, body length, chest depth, chest width, rump width, rump length, thurls width, hipbone width and chest girth) of 642 steers (Korean cattle), which was entered in the National Beef Quality Contest hosted by the Korea Animal Improvement Association from 1997 to 2001. A principal components analysis was used to classify the body types of the steers, and estimate the correlations between carcass traits and principal components for the body measurements of the first, second, third and fourth period, respectively. The first principal component of body measurements at the first, second, third and fourth period accounted for 76.0%, 83.0%, 72.7% and 57.4% of the total variance, respectively. The sum of first, second and third principal component at each period accounted for 86.69%, 90.49%, 84.62% and 77.26% of the total variance, respectively. At each period, all the first principal component of the body measurements were positive and it generally showed large framed body shape. The size of body was influenced mostly by chest depth(0.328∼0.339) and rump length(0.325∼0.341). The second, third and fourth principal component at the each period were various. There were positive correlations between principal components index of each period and carcass traits such as carcass weight(0.539∼0.755), average daily gain(0.256∼0.564), backfat thickness(0.227∼0.280), and eye muscle area(0.187∼0.344). The correlation with yield grade index(-0.246∼-0.110), however, was negative. The correlation with marbling score(0.066∼0.099) was low or statistically insignificant. According to principal component indexes of the second, third, and fourth components, the correlations with the carcass traits were various. There were no large differences between the correlations of the single body measurement trait with the carcass traits and the correlations of the first principal component indexes with the carcass traits.

Development of additive [¹¹C]CO₂ target system in the KOTRON-13 cyclotron and its application for [¹¹C]radiopharmaceutical production

Moon, B.S.,Lee, H.J.,Lee, W.K.,Hur, M.G.,Yang, S.D.,Lee, B.C.,Kim, S.E. North-Holland Physics Pub 2015 Nuclear instruments & methods in physics research. Vol.356 No.-

The KOTRON-13 cyclotron, which was developed in South Korea for the production of medical radioisotopes, has the structural limitation of only one beam-output port, restricting the production of the carbon-11 isotope. In the present study, we investigate the design of a switchable target system and develop an effective carbon-11 target in the KOTRON-13 cyclotron, for combination with the fluorine-18 target. The target system was designed by introducing a sliding-type element between the fluorine-18 and carbon-11 targets, a tailor-made C-11 target and its cooling system. For the efficient production of [<SUP>11</SUP>C]CO<SUB>2</SUB>, the desirable target shape and internal volume were determined by a Stopping and Range of Ions in Matter (SRIM) simulation program, and the target grid was modified to resist the cavity pressure during beam irradiation. We evaluated the [<SUP>11</SUP>C]CO<SUB>2</SUB> production while varying the material and thickness of the target foil, oxygen content of the nitrogen gas, and target loading pressure. Using sliding-type equipment including an additional gate valve and a high vacuum in a beam line, the bi-directional conversion between the fluorine-18 and carbon-11 targets was efficient regarding the accurate beam irradiation on both targets. The optimal [<SUP>11</SUP>C]CO<SUB>2</SUB> production for 30min irradiation at 60μA (86.6+/-1.7GBq in the target at EOB) was observed at a thickness of 19μm with HAVAR® material as a target foil and a target loading pressure of 24bar with nitrogen plus 300ppb of oxygen gas. Additionally, the coolant cavity system in the target grid and target chamber is useful to remove the heat transferred to the target body by the internal convection of water and thereby ensure the stability of the [<SUP>11</SUP>C]CO<SUB>2</SUB> production under a high beam current. In the application of C-11 labeled radiopharmaceuticals such as [<SUP>11</SUP>C]PIB, [<SUP>11</SUP>C]DASB, [<SUP>11</SUP>C]PBR28, [<SUP>11</SUP>C]Methionine and [<SUP>11</SUP>C]Clozapine, the radiochemical yields were shown to be 25-38% (decay corrected) with over 166GBq/μmol of specific activity. Consequently, the additive carbon-11 target system was successfully developed in only one output port of the KOTRON-13 cyclotron and exhibited the stable production of C-11 labeled radiopharmaceuticals.

Ex-situ catalytic pyrolysis of citrus fruit peels over mesoporous MFI and Al-MCM-41

Kim, Y.M.,Jae, J.,Lee, H.W.,Han, T.U.,Lee, H.,Park, S.H.,Kim, S.,Watanabe, C.,Park, Y.K. Pergamon ; Elsevier Science Ltd 2016 Energy conversion and management Vol.125 No.-

The thermal and ex-situ catalytic pyrolysis of different citrus peels, Citrus paradisi peel, Citrus sinensis peel, Citrus unshiu peel, and Citrus limon peel, were studied by thermogravimetric, evolved gas analysis-mass spectrometry and tandem micro-reactor-gas chromatograph/mass spectrometry analyses. Kinetic analysis revealed more complicated reaction steps and a wider range of activation energies of citrus peels than those of wood powder due to the presence of pectin in the citrus peels. Large amounts of methanol formation from each citrus peel were also recorded by evolved gas analysis-mass spectrometry and fast pyrolysis-gas chromatograph/mass spectrometry analyses at the main decomposition temperature of pectin, between 150 and 250<SUP>o</SUP>C. Mesoporous MFI was found to be a more effective catalyst for the production of mono aromatic compounds (benzene, toluene, ethylbenzene, and xylene; 3.06-4.17C%) and light olefins (ethene, propene, butene, and butadiene; 8.13-9.13C%) than Al-MCM-41 (mono aromatic compounds 0.67-0.93C% and light olefins 3.61-4.58C%) because of its higher catalytic activity in deoxygenation and aromatization due to the stronger acidity of mesoporous MFI. The yield of mono aromatic compounds over mesoporous MFI was highest from C. paradisi peel (4.17C%), followed in order by C. sinensis peel (3.83C%), C. unshiu peel (3.61C%), and C. limon peel (3.06C%), due mainly to the different contents and properties of pectin in each citrus peel. The higher activities of mesoporous MFI than Al-MCM-41 were also maintained during the 7 times sequential catalytic pyrolysis of C. paradisi peel, demonstrating the stability of mesoporous MFI catalyst.

SLA 방식 3D 프린팅 제작 수율 향상을 위한 공정모니터링 시스템 개발

이성우(S. W. Lee),이재향(J. H. Lee),최재원(J. W Choi),이지은(J. E. Lee),문혜란(H. R. Moon),신아연(A. Y. Sin),이준원(J. W. Lee),하철우(C. W. Ha) Korean Society for Precision Engineering 2023 한국정밀공학회 학술발표대회 논문집 Vol.2023 No.11

한우 비육에 관한 연구 1 . Methylthiouracil 첨가 및 Estradiol 17β - Cypionate 주사가 약령 모우 비육에 미치는 효과

김창기 ( C K Kim ),이택원 ( T W Lee ),김종욱 ( J W Kim ),배대식 ( D S Bae ),오선균 ( S K Oh ),조지훈 ( C H Cho ),김법회 ( B H Kim ),김상렬 ( S Y Kim ),배신석 ( S S Bae ) 한국축산학회 1971 한국축산학회지 Vol.13 No.1

This study was performed to affirm any effects of methylthiouracil and estradiol 17β-cypionate administered to young bulls for short term fattening. Eighteen bulls of Korean native breed, approximately 1.5 to 2 years of age and 260㎏ to 360㎏ in weight, were used in this study. All bulls had received a basal ration of soiling corn and concentrate made up of 55% grains, 40% brans and 5% others, in a period of 40 days. Bulls were divided into six groups as follows: group C was not treated, group M-2 received 2g of methylthiouracil per day, group M-3 received 3g of methylthiouracil per day, group EM-0 was injected intramusculary with 25㎎ of estradiol 17β-cypionate in the neck region 10 days after the beginning of the fattening period, group EM-2 was injected with estradiol 17β-cypionate as above mentioned and simultaneously received 2g of methylthiouracil per day, and group EM-3 was injected with estradiol 17β-cypionate as above mentioned and simultaneously received 3g of methylthiouracil per day. The results obtained were summarized as follows. 1. The average daily gain was for group C: 0.83㎏, group M-2: 1.07㎏, group M-3: 1.40㎏, group EM-0, 0.93㎏, group EM-2: 0.95㎏, and group EM-3: 1.18㎏. The M-3 group gained significantly(P$lt;0.05) more weight than C and EM-0 group. There were no significant differences in the average daily gain between the groups injected with estradiol 17β-eypionate and the control group. 2. The average daily concentrate intake was as follows: group C: 5.47㎏, group M-2: 5.00㎏, group M-3: 4.52㎏, group EM-0: 5.21㎏, group EM-2: 4.35㎏, and group EM-3: 4.61㎏. The consumption of concentrate was decreased by 17% in the M-3 group compared with the C group. There was no significant difference in the soiling corn intake among these groups. 3. Feed consumed for 1㎏ gain were decreased by the supplementation of methylthiouracil. The consumption of DCP for 1㎏ gain was in group C: 0.82㎏, group M-2: 0.59㎏, group M-3: 0.41㎏, group EM-0: 0.70㎏, group EM-2: 0.59㎏, and group EM-3: 0.50㎏. The amounts of TDN required were; group C: 6.57㎏, group M-2: 4.76㎏, group M-3: 3.39㎏, group EM-0: 5.67㎏, group EM-Z: 4.87㎏, and group EM-3: 4.08㎏. The consumption of DCP and TDN for 1㎏ gain in the M-3 group was about a half of that in the C group. 4. There was not any significant difference in the increase in body measurements among the various groups. 5. The average margins in the fattening period of 40 days were for group C: 2,950won, group M-2: 5,327won, group M-3: 9,158won, group EM-0: 3,310won, group EM-2: 3,623won, and group EM-3: 5,575won. The margin of group M-3 was about three times higher than that of group C. In short, this experiment demonstrated that methylthiouracil when fed to young native Korean bulls at the proper level 40 days before slaughter would bring a noticeable effect on weight gain, feed efficiency and economic advantage. There were no advantages from the simultaneous injecting estradiol 17β-cypionate with methylthiouracil. The proper supplementation level of methylthiouracil would appear to be 3g per head per day in this experiment.

OBSERVATIONS OF $C_3H_2 (2_{12}-1_{01})$ TOWARD THE SAGITTARIUS A MOLECULAR CLOUD

LEE C. W.,MINH Y. C.,IRVINE W. M. The Korean Astronomical Society 1993 Journal of The Korean Astronomical Society Vol.26 No.1

We have mapped the $C_3H_2\;2_{12}-1_{01}$ transition line toward the Sgr A molecular cloud on a 1' grid spacing and derived $C_3H_2$ column densities of $3\~7\times10^{14}\;cm^{-2}$ for molecular clouds of Sgr A. The fractional abundances of $C_3H_2$ relative to $H_2$ are obtained to be $3\~6\times10^{-9}$, which are slightly lower than that for the cold dark cloud TMC-1 but are enhanced by factors of 5-60 compared to those for Sgr B2 and the Orion extended ridge. We also estimate from the $C_3H_2$ column densities total masses of $\~10^6\; M_\bigodot$ for two clouds (M - 0.13 - 0.08 and M - 0.02 - 0.07), which are thought to be close to the virial equilibrium. We suggest that the large abundance of $C_3H_2$ in Sgr A may be partly due to the activities of the Galactic center.

Development of Naturally Degradable “Rice Polymer" For Organic Weed Management of Red Pepper and Rice

C.K. Kang,H.S. Nam,Y.K. Lee,S.B. Lee,B.M. Lee,Y.J. Oh,H.J. Jee,M.K. Hong,K.W. Jung,Y.J. Lee,Y.H. Choi 한국유기농업학회 2011 韓國有機農業學會誌 Vol.19 No.S

Among the developed bío-degradable polymer fílms as compared wíth transparent fílm(Whíte), black polymer fílm was sígnífícantly more effectíve for controllíng weeds ín red pepper. Also, we found that whíte and black polymer mulchíng had 81.8% and 97.9% of managing weed controllíng effects in rice, respectively. Compared to nonmulched rice paddy with water supply, the non-mulched rice paddy wíthout any water supply has stopped its growth at 41 days after transplantíng, whíle polymer -mulched rice paddy without water supply had about 60% of normally growing rice plants. This shows the polymer treatment has a remarkable effect on water and power saving, solution of herbicidal resistance, avoidance of herbícidal influence to eco-system etc. When the naturally decomposíng polymer was used, a temperature was elevated as high as 4.7 ℃ on maximum and 2.6 ℃ on average. Also the naturally decomposing polymer accelerated rooting by 7 days and lowered a stress level from transplanting. The weed control effect mulched by polymer was remarkable as 98. 7%. The p이ymer now, after 294 days treated on the rice paddy, has been completely decomposed.