• Title/Summary/Keyword: BOC

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Dertermination of Alkylphenols, Chlorophenols and Bisphenol A in Various Samples by Freezing Filtration and GC/MS-SIM

  • Kim, Hyub
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.68.1-68.1
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    • 2003
  • A method for determination 11 endocrine disrupting chemicals of phenols in various samples was deloped. The alkylphenols, chlorophenols and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) followed by two work-up methods for comparison; isobutoxycarbonyl (isoBOC) derivatization method and tert-butyldimethylsilyl (TBDMS) derivatization method. Eleven endocrine disrupting chemicals (EDCs) of phenols in biological samples were extracted with acetonitrile and then acetonitrile layer was refrigerated at -60$^{\circ}C$ for 2 hours (freezing filtration). (omitted)

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Synthesis of Dynorphin B Analogues by Solid-Phase Method (고상법에 의한 Dynorphin B 유도체의 합성)

  • Kook, Soon Uoong;Son, Ki Nam
    • Journal of the Korean Chemical Society
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    • v.42 no.2
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    • pp.214-219
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    • 1998
  • Dynorphin B analogues, $[Arg^{11}, D-Ala^{12}]$dynorphin B, $[D-Ala^2, Ala^6, Arg^{11}, D-Ala^{12}]$dynorphin B, and dynorphin B (1-11) were synthesized by solid-phase method. A chloromethylated polystyrene resin cross-linked with 2% divinylbenzene was substituted with Thr in ethanol to contain 1.20 mmol Thr/g of resin. All amino groups of amino acids were protected with t-Boc group and 2,6-dichlorobenzyl and nitro groups were used to protect the side chains of Tyr and Arg, respectively. Stepwise synthetic method was applied for synthesis of the products. Dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBT) were used as the coupling reagents. The crude peptides were purified by gel filteration on Sephadex LH-20 column $(2 \times 50 cm)$ using MeOH/MeCN (3/1) and then characterized with HPLC, amino acid analyzer.

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Analysis of Galileo GIOVE-A E1 Signal and RF Front-End Bandwidth Effects (갈릴레오 GIOVE-A E1 신호 분석 및 RF 프론트엔드 대역폭 영향 분석)

  • Lee, Byung-Hyun;Im, Sung-Hyuck;Jee, Gyu-In;Ko, Sun-Jun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.8
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    • pp.767-773
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    • 2008
  • Galileo is a new civil Global Navigation Satellite System(GNSS) developed by Europe. GIOVE-A, a satellite to test Galileo system performance, transmits navigation signal on orbit. Evaluation of Galileo system and development of Galileo receiver needs to analyze GIOVE-A signals. In this paper, we received GIOVE-A signals and processed it using GIOVE-A Interface Control Document(ICD). Signal acquisition, tracking and navigation message decoding made grasping current signal status possible. Bandwidth increase by BOC modulation is one of the difference from GPS. Therefore, we investigated feasibility of conventional GPS L1 RF front-end to receive GIOVE-A E1 signal by evaluation of receiving performance of navigation signal on each bandpass filter of RF front-end.

Comparison of rice flour properties of different cultivars using wet and dry milling processes

  • Park, Jiyoung;Lee, Seuk-Ki;Park, Hye-Young;Choi, Hye-Sun;Cho, Dong-Hwa;Han, Sang-Ik;Lee, Kyung Ha;Oh, Sea-Kwan
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.286-286
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    • 2017
  • We conducted to compare the characteristics of rice flours according to the different milling processes. Five rice varieties (Oryza sativa L.) with different amylose content were prepared by wet and dry milling processes. The moisture contents of wet-milled rice flours (WMR) was mostly three-time higher than those of dry-milled flours (DMR). Water absorption index (WAI), water solubility index (WSI) and swelling power (SP) increased in proportion to temperature ($50-90^{\circ}C$). WAI, WSI, SP of DMR showed higher value than those of WMR. Baeokchal (BOC) which is waxy rice cultivar was significantly high level of WSI. Pasting properties of DMR except BOC cultivar resulted in higher peak viscosity, trough viscosity, final viscosity and Setback. The levels of resistant starch in the four cultivars except Dodamssal (DDS) were under 1% irrespective of Milling processes, whereas the resistant starch contents of DMR and WMR in DDS was 9.18 and 6.27, respectively. Damaged starch content of WMR were less than those of DMR, moreover, negative correlation was observed between amylose content and damaged starch of rice cultivars. These results suggest that the properties of rice flour varied depending on the milling methods and varieties, and it could be a reference for selecting the appropriate processing purposes.

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Fabrication and Characterization of BixCel-xO2-x/2 Electrolytes for IT-SOFC (중온형 고체산화물 연료전지BixCel-xO2-x/2 전해질의 제조 및 특성평가)

  • Han, Ju-Hyeng;Lee, In-Sung;Lee, Dokyol
    • Journal of the Korean Ceramic Society
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    • v.42 no.12 s.283
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    • pp.808-815
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    • 2005
  • [ $Bi_xCe_{l-x}O_{2-x/2}$ ](BD C : Bismuth Doped Ceria) powders with x = 0.1, 0.2, and 0.3 were synthesized using the Glycine Nitrate Process (GNP). They were then calcined at $500^{\circ}C$ for 2 hand sintered in a pellet or rod form at 900, 1000 or $1100^{\circ}C$ for 4 h for characterization as the alternative electrolyte material for intermediate temperature solid oxide fuel cells. The BDC powder consisted of a single phase of $CeO_2-Bi_2O_3$ solid solution in the as-synthesized state as well as in the as-calcined state with a mean powder size of 4.5nm in the former state and 6.5 - 10.1nm in the latter. On the contrary, the second phase of $\alpha-Bi_2O_3$ was observed to have been formed in the sinter with its amount increasing roughly with increasing temperature or $Bi_2O_3$ content. The BOC powder was superior in sinterability to other alternative electrolyte materials such as GDC, ScSZ, and LSGM with the minimum sintering temperature for a relative density of $95\%$ or larger as low as $1100^{\circ}C$. The ionic conductivity of BOC increased with $Bi_2O_3$ content and the maximum value of 0.119 S/cm was obtained at $800^{\circ}C$ for $Bi_{0.3}Ce_{0.7}O_{1.85}$.

Synthesis of Indoline tri-isopropyl benzene sulfonamide as a potential new asymmetric catalyst (새로운 술폰아미드계의 촉매의 합성)

  • Yun, In-Gwon;Kim, Hwan-Cheol
    • The Journal of Natural Sciences
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    • v.7
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    • pp.47-51
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    • 1995
  • In order to develope new asymmetric catalyst, we synthesized the following new sulfonamide derivatives start from S-Indoline-2-Carboxylic Acid via the following 5 steps. Hydroxy methyl derivative(1) was thus treated with methane sulfonyl chloride in the presence of triethylamine as base to give mesylated derivative(2) in 85% of isolated yield. The mesylate compound (2) was treated with excess sodium azide to give Azido derivative (4) in 95% isolated yield. Azido compound (3) was then reduced to the corresponding amino derivative in near quntitative yield by the hydrogenation under hydrogen atmospere in the presence of catalytic amount of Pd-C. The amino derivative (4) was converted to its sulfonamide derivatives by the treatment of compound(4) with triisopropyl benzene sulfonyl chloride in the presence of triethyl amine as base. Finally t-BOC group of the compound(5) was removed by the treatement of excess Trifluoro-acetic acid in near quantitative yield to give the target sulfonamide derivative (7) .in this paper we prepared compound(6) in 49% overall yield via the 5 steps of synthesis starting from t-Boc- 2-hydroxy methyl indoline(1) which cab be easily prepared from commercial available S-indoline-2-carboxylic acid by known methods. we plan to apply this new catalyst for the asymmetric reduction , diels-alder reaction, aldolcondensation reaction in due courses.

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Physicochemical Characteristics of Sikhye (Korean Traditional Rice Beverage) Using Foxtail Millet, Proso Millet, and Sorghum (조, 기장, 수수를 이용한 식혜의 이화학적 특성)

  • Jeong, Mi Seon;Ko, Jee Yeon;Song, Seuk Bo;Lee, Jae Saeng;Jung, Tae Wook;Yoon, Young Ho;Oh, In Seok;Woo, Koan Sik
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.11
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    • pp.1785-1790
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    • 2014
  • This study was carried out to compare the physicochemical characteristics and sensory qualities of Sikhye (Korean traditional rice beverage) prepared with foxtail millet, proso millet, and sorghum. The cultivated varieties were Setaria italica Beauv. cv. Samdamae (SDM) and Samdachal (SDC), Panicum miliaceum L. cv. Ibaekchal (IBC), Sorghum bicolor (L.) Moench cv. Nampungchal (NPC), Donganme (DAM), Oryza sativa cv. Ilpum (IP), and Baegokchal (BOC). The brix degrees of SDM, SDC, IBC, NPC, DAM, IP, and BOC Sikhye were 9.53, 8.63, 5.67, 7.57, 6.27, 12.50, and $12.27^{\circ}Bx$, respectively. There were no significant differences in pH (5.99~6.10) among the groups. The highest turbidity was 1.07 in DAM Sikhye. The L-value, a-value, and b-value were 30.85~41.11, -0.34~2.52, and 2.56~5.67, respectively. Total polyphenol contents of SDM, SDC, IBC, NPC, DAM, IP, and BOC Sikhye were 241.52, 213.69, 202.34, 258.25, 193.24, 160.81, and $170.31{\mu}g\;GAE/mL$, respectively. Total flavonoid contents of Sikhye were $19.21{\sim}54.30{\mu}g\;CE/mL$. The highest DPPH and ABTS radical scavenging activities were $16.85{\pm}0.39$ and $64.75{\pm}2.92mg\;TE/100mL$ in DAM Sikhye, respectively. Finally, the sensory evaluation results indicate that there were significant differences in appearance, aroma, and taste between the groups, and SDM Sikhye was similar with IP and BOC.

Characterization of a Serine Protease from Neungee [Sarcodon aspratus(Berk, ) S. Ito] (능이[Sarcodon aspratus(Berk, ) S. Ito]에서 분리한 단백질 가수분해 효소의 특성)

  • 엄태붕;유관성;김미경;류재수;손희숙;이태규
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.20 no.1
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    • pp.35-39
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    • 1991
  • Properties of a protease purified from Neungee[Sarcodon aspratus(Berk, ) S. Ito] have been investigated. The enzyme displays a glycosylated serine protease. The enzyme is able to hydrolyze alanine glycine methionine glutamine and cysteine of N-CBZ and N-t-BOC-L-amino acid derivatibes relatively strongly but splits valine proline and isoleucine derivatives with low affinity which means the enzyme has the broad substrate spectrum toward the amino acids. Interestingly the enzyme was inhibited by bromelain inhibitor. That is the active site environ-ment of the enzyme is believed to be similar to that of bromelain However peptide mapping studies show that the two enzymes have distinct different cleavage sites.

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Antibradykinin Effects of the Non-peptide Antagonists of Mixture Libraries Prepared by Solution-phase Combinatorial Synthesis

  • KAM Yoo Lim;CHOO Hea-Young P.
    • Biomolecules & Therapeutics
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    • v.13 no.3
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    • pp.181-184
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    • 2005
  • The solution-phase combinatorial synthesis of iminodiacetic acid triamide libraries linked to 1-(4-chlorobenzhydryl)piperazine has been reported. Ten mixture libraries, each containing 5 components, were synthesized in 4 steps from N-BOC-iminodiacetic acid anhydride. Antibradykinin effects of the mixture and individual libraries were compared using guinea-pig ileum smooth muscle. The changes in the inhibition were also observed by testing the combination of two different compounds from the same library. We found out the correlation between the inhibition of mixtures and that of individual libraries. It is possible to choose the mixtures with relatively high inhibitory effects to find out the most effective individual compound for further synthesis.

Design and Implementation of a Collaborative Software Development Management System (협업적 소프트웨어 개발 관리 시스템의 설계 및 구현)

  • Han, Kwan-Hee;Song, Hee-Seok
    • Journal of Information Technology Services
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    • v.5 no.2
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    • pp.79-92
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    • 2006
  • Since software development team members have been more geographically spread due to the globalization of business and Internet technologies, the management of deliverables and communication efforts for developing high-quality software products on time is becoming more complicated. Among the functional requirements for collaborative software development management, the manipulation of shared information objects is essential for the collaborative work among distributed development team members. This paper proposes an integrated information object management framework comprised of a so-called BOC (Bill Of Class) scheme and a standardized software part dictionary for managing shared information objects efficiently among distributed co-workers. In order to manage these complex information objects, the proposed framework adopt product structures represented by Bills Of Materials (BOM) as stems for integrating the various information objects. Based on the proposed framework, a collaborative software development management system (CSDMS) is implemented, and the functionalities and the structure of the system are also described in this paper. The proposed system provides sufficient functionalities for the change management of information objects and the management of their relationship to other objects rather than existing system.