• Title/Summary/Keyword: 17B

Search Result 6,636, Processing Time 0.033 seconds

The Synthesis and Characterization of Some Novel Thioethers: Thio-Subsituted [3]Cumulenes, -1-Buten-3-ynes and Buta-1,3-dienes

  • Ibis, Cemil;Sahin, Aysecik
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.8
    • /
    • pp.2255-2260
    • /
    • 2010
  • In this study, some novel thiosubstituted butenyne (3a-d, 7b, 15b), butadiene (4a-b, 4d, 5a, 5c, 6b, 8e, 9c, 10b, 16b, 18e) and [3]cumulene (11a-b with isomer 3a-b, 12a with isomer 13a, 14b, 17e) compounds were synthesized from the reaction of 2H-pentachloro-1,3-butadiene with thiols. The new compounds were characterized by elemental analysis, mass spectrometry, UV-vis, IR, 1H NMR, NMR ($^{13}C$ or APT) spectroscopy.

Corrosion and Surface Mechanical Properties of Fe-Gd-B Alloys (Fe-Gd-B 합금의 내식성과 표면 물성 평가)

  • Baek, Yeol;Choe, Yong
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2017.05a
    • /
    • pp.119.1-119.1
    • /
    • 2017
  • Fe-(10, 24 wt.%) Gd-B 합금을 진공 주조하고 상분석과 내식성 평가 및 표면 경도를 측정하였다. 주조된 Fe-10 wt.% Gd-B 합금의 상은 주로 $Fe_2Gd$, $Fe_3Gd$, $B_4FeGd$, $GdB_2$이었으며, Fe-24 wt.% Gd-B 합금은 주로 $Fe_2Gd$, $Fe_3Gd$, $Fe_9Gd$, $Fe_{17}Gd_2$, $B_4FeGd$, $GdB_2$이었다. 인공해수 분위기에서의 부식 속도와 부식 전위는 각각 2.771, 2.914 [$mA/cm^2$]과 -623.9, -607.8 [$mV_{SHE}$]이었다. 표면 경도는 각각 220, 208 [Hv] 이었다. Gd 함량이 증가할수록 부식 속도는 증가하였고 표면 경도는 감소하는 경향을 보였다.

  • PDF

Effect of Ball-Milling on the Superconducting Properties of C and C-Based Compound Doped $MgB_2$ (탄소 및 탄소화합물이 도핑된 $MgB_2$ 초전도체의 볼밀링 효과)

  • Ahn, Jung-Ho;Jang, Min-Kyu;Oh, Sang-Jun
    • Progress in Superconductivity
    • /
    • v.10 no.1
    • /
    • pp.17-22
    • /
    • 2008
  • We have examined the effect of ball-milling on the superconducting properties of $MgB_2$ doped with C. The ball-milling of pre-reacted $MgB_2$ powder was carried out in dry or wet state using C or diethylenetriamine ($C_{4}H_{13}N_3$) as additives. The diethylenetriamine, whose chemical formula contains no oxygen, was chosen to avoid an excess oxidation during doping. The superconducting transition temperature (Tc) of the ball-milled or doped $MgB_2$ powders was only slightly smaller than that of undoped $MgB_2$. The critical current density (Jc) of the highly ball-milled $MgB_2$ was higher than that of C-doped $MgB_2$. The addition of diethylenetriamine was detrimental to Jc, although Tc was almost unchanged.

  • PDF

Expression of IL-17 Homologs and Their Receptors in the Synovial Cells of Rheumatoid Arthritis Patients

  • Hwang, Sue-Yun;Kim, Ho-Youn
    • Molecules and Cells
    • /
    • v.19 no.2
    • /
    • pp.180-184
    • /
    • 2005
  • IL-17 is a major proinflammatory cytokine secreted by activated T-lymphocytes that accumulates in the inflamed joints of rheumatoid arthritis (RA) patients. Additional IL-17-related molecules and their receptors have been discovered and may also contribute to RA pathogenesis. We examined the expression of the prototypic IL-17 (IL-17A) and its homologs, IL-17B-F, by RT-PCR analyses of synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from RA patients. We also tested for induction of the IL-17 receptor homologs upon stimulation of the fibroblast-like synoviocytes (FLSs) of RA patients with IL-17. The patients' SFMCs expressed IL-17C, E and F in addition to IL-17A. As in the case of IL-17, IL-15 appears to be the major inducer of these homologs in RA SFMCs. We detected transcripts of IL-17R, as well as those of IL-17RB, C and D, in the FLSs of RA patients. Whereas IL-17R expression increased upon in vitro stimulation with IL-17, expression of IL-17RB, C and D was unchanged. However the possibility of cross-interaction between other IL-17 homologs and receptor isoforms remains to be investigated. Our data suggest that these additional homologs should also be considered as targets for immune modulation in the treatment of RA joint inflammation.

Studies on Bacterial Characteristics of Bacillus cereus Group LS-1 Isolated from Suyeong Bay (수영만에서 분리된 Bacillus cereus Group LS-1 의 세균학적 특성에 관한 연구)

  • 성희경;이원재;김용호;함건주
    • Korean Journal of Microbiology
    • /
    • v.30 no.5
    • /
    • pp.339-346
    • /
    • 1992
  • These studies were carried out to identify Bacillus cereus group 1..5-] strain isolated from 5uyeong Bay. This strain was differentiated from B. cereus group using conventional, API system and fatty acid composition analysis. Colony characteristics were opague. mucoid, entire margin. convex. circular and non hemolysis on sheep blood agar plates, and were observed with central spore forming positive bacilli in a Gram stained preparation. and had no motility. The carbohydrates tested; glucose.maltose, and sucrose were assimilated but neither trehalose nor salicin were assimilated. This strain ultilized gelatin and was also inhibited by 6.5% NaCI. The results of biochemical examination were differented from B. cereus group LS-1 compared with others B. cereus group. The fatty acid composition contained major amounts of branched chain acids. iso $C_{15}$ and iso $C_{13}$ and the range of chain length was $C_{12}$ to C"$C_{17}$ and n$C_{15}$, acid was not detected. Automated fatty acid computer profile indicated "B. mycoides GC subgroup B of 0.312 similarity index." The results agreed with other research cases. On the other hand. A TB computer prolile index of API system (API 50 CHB & API 20E) identified" Doubtful profile of 99.7% B. firmus" . These results were presented with considerable discrepancies between API system and fatty acid analysis. With 67 biochemical characters. the similarity matrix of B. mycaides (KCTC 1033). B. thuringiensis (KCTC 1033). B. cereus (5-3) and B. mycoides (S-12) showed 42%. 42%. 59%, and 52%. respectively. Through the key tests and fatty acid analyses. we could notice the appearance of B. mycoides of the B. cereus group and this leads us to suspect the existence of a new biotype B. mycoides.

  • PDF

ErbB2 kinase domain is required for ErbB2 association with β-catenin (ErbB2의 kinase 영역이 β-catenin과 ErbB2의 결합에 필요하다)

  • Ha, Nam-Chul;Xu, Wanping;Neckers, Len;Jung, Yun-Jin
    • Journal of Life Science
    • /
    • v.17 no.3 s.83
    • /
    • pp.356-361
    • /
    • 2007
  • To investigate the region of ErbB2 for the $ErbB2-{\beta}-catenin$ interaction, a proteasome $resistant-{\beta}-catenin$ and various ErbB2 constructs were transfected in COS7 cells. ErbB2 proteins were immunoprecipitated, and coimmunoprecipitated ${\beta}-catenin$ was examined by Western blotting. ${\beta}-catenin$ coimmunoprecipitated with full length ErbB2. Of the truncated ErbB2 proteins DT (1-1123), DHC (1-1031) and DK (1-750), the ErbB2 constructs containing the kinase domain, DT and DHC, precipitated together with ${\beta}-catenin$ but DK containing no kinase domain did not. To further test the requirement of the kinase domain for ${\beta}-catenin-ErbB2$ interaction, the presence of ${\beta}-catenin$ in the immunocomplex was examined following transfection with an ErbB2 mutant (${\triangle}750-971$) whose kinase domain is internally deleted and subsequent immunoprecipitation of the ErbB2 mutant. ${\beta}-catenin$ was not detected in the immunocomplex. These results suggest that the ErbB2 kinase domain comprises a potential site for ${\beta}-catenin$ binding to the receptor tyrosine kinase.

Effects of Characteristics of Ovarian follicular Fluid and Ant-Inhibin Serum on Steroid Hormone Secretion by Hanwoo Granulosa Cells In Vitro (한우 난소의 Follicular Fluid의 특징과 과립막 세포의 스테로이드호르몬 분비에 대한 Anti-Inhibin Serum의 첨가효과)

  • 성환후;민관식;양병철;노환국;최선호;임기순;장유민;박성재;장원경
    • Korean Journal of Animal Reproduction
    • /
    • v.25 no.2
    • /
    • pp.119-124
    • /
    • 2001
  • This study was performed to investigate the effects of the peptide to carrier ratio on the immune and biological functions to inhibin immunization in Hanwoo. A peptide sequence kom the alpha -subunit (19~32 peptide) of porcine inhibin was synthesized for antigen and conjugated to human serum albumin(HSA) for carrier protein. Anti-inhibin sera(AI) were produced 52 day later from rabbit after injection of inhibin-$\alpha$ -subunit peptide conjugator for antigen with the interval of 2 weeks. Immune-blotting analysis using antibody specific fur inhibin-$\alpha$ subunits revealed that the inhibin was detected at 1.0 cm bovine follicular fluid(bFF). However, each stage of corpus lutea and 0.1 cm of follicular fluid were not detected. The maximal contents of estradiol-17 $\beta$ in Hanwoo ovarian follicular fluid were detected at 2.0 cm of follicular size(diameter), but the mean total contents of these hormone decreased significantly with decreasing diameter of follicles. However, progesterone contents of follicular fluid were high at 1.0 cm of follicle. Progesterone secretion by Hanwoo granulosa cell cultured for 48 hr in vitro was significantly (p<0.05) inhibited in 5% bFF and 5% bFF + 5% AI addition group compared with control group. Estradiol-17 $\beta$ secretion by Hanwoo granulosa cell cultured for 48 hr in vitro was significantly (p<0.05) increased in 5% AI and 5% AI + 5% bFF addtion group compared with control group. However, the groups added 5% AI were not changed compared to control groups in progesterone and estradiol-17 $\beta$. Taken together, we suggested that inhibin in the mature FF plays a pivotal role on the biosynthesis of steroid hormone of follicular cells during follicular development.

  • PDF

A Study on the Performance Improvement of Turbo Coded OFDM Systems Considering Frequency Offset (주파수 오프셋을 고려한 Tued OFDM 시스템의 성능 개선에 관한 연구)

  • 이영춘;박기식
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.5 no.5
    • /
    • pp.908-915
    • /
    • 2001
  • In this paper, it is analyzed theoretically that the performance degradation, caused by carrier frequency offset, in an OFDM/M-ary PSK system. Then, when Turbo coding is adopted to an OFDM/M-ary PSK system, the degree of performance enhancement is evaluated. Finally, the maximum frequency offset is calculated to satisfy the BER performance required in a Turbo coded OFDM/M-ary PSK system. As results of analysis, it is shown that the more the number of M-ary is, the worse the BER performance is. Moreover, 7dB, 9dB, and 17dB of $E_b/N_o$ are required in QPSK, 8PSK and 16PSK systems, respectively in order to satisfy the error performance, $BER=10^{-3}$ for voice communication. If $E_b/N_o$ are 10㏈ and 15㏈, the frequency offset should be below 0.05 and 0.075, respectively, for voice communication. When Turbo coding is adopted to an OFDM/M-ary PSK system, the less the number of M-ary is, the greater the performance enhancement of Turbo coding is. If the number of a M-ary system of the system is below 16, it is found that required $E_b/N_o$ is about 8dB to satisfy $BER=10^{-5}$ Moreover, in the system the Turbo coding scheme, voice communication is available with greatly low$E_b/N_o$, and 8dB of $E_b/N_o$ is enough for data communication regardless of the permission range of frequency offset.

  • PDF

BVRI Standardization of the CCD Photometric System of Sobaeksan Optical Astronomy Observatory (소백산 천문대 CCD 측광계의 BVRI 표준화)

  • Jeong, Jang-Hae;Kim, Chun-Hwey;Lee, Yong-Sam
    • Journal of Astronomy and Space Sciences
    • /
    • v.25 no.2
    • /
    • pp.87-100
    • /
    • 2008
  • A total of 792 CCD images of V523 Cas were obtained on four nights of Jan. 2003 with the bvri CCD photometric system attached to a 61cm reflector of Sobaeksan Optical Astronomy Observatory (SOAO). The 17 standard stars in the images were used to establish transformation relations between our bvri system and the standard Johnson-Cousins BVRI system. We derived the tentative equations of transformation between two photometric systems as follows; V=v-0.0689(B-V)+0.0063, B-V=1.3197(b-v)-0.1733, V-R=0.9210(v-r)-0.1309, R-I=0.8892(r-i)-0.1055. Using these equations standard V magnitudes and their color indexes (B-V, V-R, R-I) for 57 stars in the field of the image were determined.

A Study on the Performance Analysis and Improvement of Physical Layer for Next Generation ITS/DSRC (차세대 ITS/DSRC 물리계층 성능분석 및 개선에 관한 연구)

  • Jeong, Jae-Seung;Park, Sung-Jin;Lee, Byung-Seub
    • Journal of Advanced Navigation Technology
    • /
    • v.5 no.1
    • /
    • pp.37-44
    • /
    • 2001
  • In this paper, the channel environment for next generation ITS/DSRC which is developed for 10Mbps is modeled with ray tracing technique and, we analyzed BER of OFDM which has an advantage over reducing the effect of ISI with multi-carrier and guard time, occuping bandwidth on 6-ray channel environment. Also, we applied the one-tap equalizer to improve the performance of BER. In case only OFDM is applied with 32 sub-carrier, the result of BER is under $10^{-6}$ from 10 to 100m if $E_b/N_0$ is more than 23dB. But in case OFDM and one-tap equalizer are applied with 32 sub-carrier, $E_b/N_0$ is required of about 17dB to achieve BER under $10^{-6}$.

  • PDF