Effects of C and Al on hydrogen embrittlement mechanism in medium Mn-Ni steels

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Investigation of grain-boundary effect on hydrogen behaviors in single- and poly- crystalline medium-entropy CrCoNi alloy

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Direct Effects of Propofol on the Left Ventricular Papillary Muscles of Rats Compared with Other Intravenous Induction Agents

The isometric contractions of isolated rat myocardiums to propofol were compared with those to thiopental, etomidate, and brevital. 40 rat left ventricular papillary muscles were evenly divided into four groups and were exposed to the mean maximum post-induction plasma concentration and its double concentration in random order. Both concentrations of propofol showed 17.5% to 22.5% depression in Tpd, +dp / dt.nax, and -dp / dt.nax, which was the greatest among four agents, while thiopental revealed the least depression. Brevital and etomidate depressed three parameters to a similar degree. In Tr, 1FT, and RT90%, there were only negligible changes in all four drugs in both concentrations. We might say that the depression of myocardial contractility by propofol is, in part,a important cause of hypotension. Therefore propofol should be used with caution in patients with a depressed myocardial contractility

PAGaN I: Multi-Frequency Polarimetry of AGN Jets with KVN

Active Galactic Nuclei (AGN) with bright radio jets offer the opportunity to study the structure of and physical conditions in relativistic outflows. For such studies, multi-frequency polarimetric very long baseline interferometric (VLBI) observations are important as they directly probe particle densities, magnetic field geometries, and several other parameters. We present results from first-epoch data obtained by the Korean VLBI Network (KVN) within the frame of the Plasma Physics of Active Galactic Nuclei (PAGaN) project. We observed seven radio-bright nearby AGN at frequencies of 22, 43, 86, and 129 GHz in dual polarization mode. Our observations constrain apparent brightness temperatures of jet components and radio cores in our sample to $>10^{8.01}$ K and $>10^{9.86}$ K, respectively. Degrees of linear polarization $m_{L}$ are relatively low overall: less than 10%. This indicates suppression of polarization by strong turbulence in the jets. We found an exceptionally high degree of polarization in a jet component of BL Lac at 43 GHz, with $m_{L} \sim$ 40%. Assuming a transverse shock front propagating downstream along the jet, the shock front being almost parallel to the line of sight can explain the high degree of polarization.Comment: 14 pages, 17 figures, 4 tables. To appear in JKAS (received 2015 July 27; accepted 2015 October 25). Note the PAGaN II companion paper by J. Oh et a

PAGaN II: The Evolution of AGN Jets on Sub-Parsec Scales

We report first results from KVN and VERA Array (KaVA) VLBI observations obtained in the frame of our Plasma-physics of Active Galactic Nuclei (PAGaN) project. We observed eight selected AGN at 22 and 43 GHz in single polarization (LCP) between March 2014 and April 2015. Each source was observed for 6 to 8 hours per observing run to maximize the $uv$ coverage. We obtained a total of 15 deep high-resolution images permitting the identification of individual circular Gaussian jet components and three spectral index maps of BL Lac, 3C 111 and 3C 345 from simultaneous dual-frequency observations. The spectral index maps show trends in agreement with general expectations -- flat core and steep jets -- while the actual value of the spectral index for jets shows indications for a dependence on AGN type. We analyzed the kinematics of jet components of BL Lac and 3C 111, detecting superluminal proper motions with maximum apparent speeds of about $5c$. This constrains the lower limits of the intrinsic component velocities to $\sim0.98c$ and the upper limits of the angle between jet and line of sight to $\sim$20$\deg$. In agreement with global jet expansion, jet components show systematically larger diameters $d$ at larger core distances $r$, following the global relation $d\approx0.2r$, albeit within substantial scatter.Comment: 13 pages, 15 figures, 4 tables. To appear in JKAS (received 2015 August 31; accepted 2015 October 15). Note the PAGaN I companion paper by J.-Y. Kim et a

The Globular Cluster System of M60 (NGC 4649). I. CFHT MOS Spectroscopy and Database

We present the measurement of radial velocities for globular clusters in M60, giant elliptical galaxy in the Virgo cluster. Target globular cluster candidates were selected using the Washington photometry based on the deep 16\arcmin \times 16\arcmin images taken at the KPNO 4m and using the $VI$ photometry derived from the HST/WFPC2 archive images. The spectra of the target objects were obtained using the Multi-Object Spectrograph (MOS) at the Canada-France-Hawaii Telescope (CFHT). We have measured the radial velocity for 111 objects in the field of M60: 93 globular clusters (72 blue globular clusters with $1.0\le(C-T_1)<1.7$ and 21 red globular clusters with $1.7\le(C-T_1)<2.4$), 11 foreground stars, 6 small galaxies, and the nucleus of M60. The measured velocities of the 93 globular clusters range from $\sim 500$ km s$^{-1}$ to $\sim 1600$ km s$^{-1}$, with a mean value of $1070_{-25}^{+27}$ km s$^{-1}$, which is in good agreement with the velocity of the nucleus of M60 ($v_{\rm gal}=1056$ km s$^{-1}$). Combining our results with data in the literature, we present a master catalog of radial velocities for 121 globular clusters in M60. The velocity dispersion of the globular clusters in the master catalog is found to be $234_{-14}^{+13}$ km s$^{-1}$ for the entire sample, $223_{-16}^{+13}$ km s$^{-1}$ for 83 blue globular clusters, and $258_{-31}^{+21}$ km s$^{-1}$ for 38 red globular clusters.Comment: 29 pages, 8 figures. To appear in Ap