Robust Magnetic Order of Ce 4f-electrons Coexisting with Superconductivity in CeFeAsO1−xFx

T. Shang,L. Jiao,J. Dai,H. Q. Yuan,F. F. Balakirev,W. Z. Hu,N. L. Wang 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12

The electrical resistance of CeFeAsO1−xFx (x = 0.06 and 0.08) has been measured in magneticfields up to 40 T. At zero field, the sample with x = 0.06 shows a structural phase transition aroundTS 100 K, followed by a spin-density-wave (SDW) transition around TSDW 30 K. For x =0.08, the structural phase transition is suppressed down to TS 60 K without a clear anomalyassociated with the Fe-SDW transition, and superconductivity shows up at TC 25 K. At lowertemperatures, both samples show a clear resistive peak around TN 4 K, which is associated withthe antiferromagnetic (AFM) transition of Ce 4f-electrons. Strikingly, zero resistance is recoveredupon a further lowering of the temperature to below TN for x = 0.08. Moreover, we found thatthe AFM transition of Ce 4f-electrons at 4 K hardly change when a magnetic field of up to 40 Twas applied. This was true even in the case of x = 0.08, for which the superconductivity had beenpartially suppressed at such a large field.

AKARI-SDSS-GALEX SURVEYS: SPECTRAL ENERGY DISTRIBUTIONS OF NEARBY GALAXIES

Buat, V.,Yuan, F.T.,Takeuchi, T.T.,Giovannoli, E.,Heinis, S. The Korean Astronomical Society 2012 天文學論叢 Vol.27 No.4

A sample of nearby galaxies was built from the AKARI/FIS all sky survey cross-correlated with the SDSS and GALEX surveys. The spectral energy distributions from 0.15 to 160 microns of these galaxies are analysed to study dust attenuation and star formation properties. The calibrations of the amount of dust attenuation as a function of the IR-to-UV flux ratio and the FUV-NUV colour are re-investigated: the former one is confirmed to be robust and accurate whereas the use of the FUV-NUV colour to measure dust attenuation is found highly uncertain. The current star formation rate given by the SED fitting process is compared to that directly obtained from the UV and total IR luminosities. It leads to an accurate estimate of dust heating by old stars. We emphasize the importance of such a sample as a reference for IR selected star forming galaxies in the nearby universe.

The Additivity of True or Apparent Phosphorus Digestibility Values in Some Feed Ingredients for Growing Pigs

Fang, R.J.,Li, T.J.,Yin, F.G.,Yin, Y.L.,Kong, X.F.,Wang, K.N.,Yuan, Z.,Wu, G.Y.,He, J.H.,Deng, Z.Y.,Fan, M.Z. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.7

Two experiments were conducted to determine the additivity of apparent or true digestibility of phosphorus (P) in soybean meal (SBM), peas, faba beans, corn, oats, broken rice meal, rough rice meal, buckwheat, and sorghum for growing pigs. Chromic oxide (0.3%) was used as a digestion marker in both experiments. Each experiment lasted for 12 d, which consisted of a 7-d dietary adaptation period followed by a 5-d fecal collection period. Experiment 1 involved 6 diets: the SBM-based control diet; 4 diets with corn, oats, rough rice meal and broken rice meal substituted for SBM; and an additional diet with a representative mixture of the 5 ingredients. In Experiment 2, 6 diets were prepared similarly, except that the tested ingredients besides SBM were faba beans, peas, buckwheat, and sorghum. In each experiment, six barrows with an initial average individual BW of 20.5 kg were fed one of the six diets according to a $6{\times}6$ Latin square design. The apparent and true P digestibility values for the nine tested ingredients were determined by the substitution method. There were no differences (p>0.05) between the determined and the predicted true P digestibility values for the mixture of ingredients in Experiments 1 and 2. However, the determined and the predicted apparent P digestibility values for the mixture of ingredients differed (p = 0.059) in Experiment 1, but not in Experiment 2. These results indicate that true P digestibility values are additive in ingredients containing low levels of phytate phosphorus and anti-nutritional factors, whereas the apparent P digestibility values are not always additive in single feed ingredients for growing pigs.

STAR FORMATION RATE CALIBRATIONS FOR WISE LUMINOSITIES

Yuan, F.T.,Takeuchi, T.T,Buat, V.,Burgarella, D. The Korean Astronomical Society 2012 天文學論叢 Vol.27 No.4

Starting from an infrared selected GALEX-SDSS-2MASS-AKARI sample of local star forming galaxies, we built mock samples from redshift 0 to 2.5 to investigate star formation rate (SFR) calibrations using WISE luminosities. We find W3 and W4 band fluxes can indicate SFRs with small scatters when the rest-frame wavelengths are longer than ${\sim}6{\mu}m$. When the wavelength becomes shorter, the observed luminosities are more tightly connected to the emission of old stellar populations than dust, therefore lose the reliability to trace the SFR. The current SFR calibrations are consistent with previous studies.

Genotypexenvironment interactions for chilling tolerance of rice recombinant inbred lines under different low temperature environments

Jiang, W.,Lee, J.,Chu, S.H.,Ham, T.H.,Woo, M.O.,Cho, Y.I.,Chin, J.H.,Han, L.,Xuan, Y.,Yuan, D.,Xu, F.,Dai, L.,Yea, J.D.,Koh, H.J. Elsevier Scientific Pub. Co 2010 Field crops research Vol.117 No.2

Chilling injury is one of the major environmental stresses in rice cultivation in high-latitude and high-altitude regions. In this study, we cultivated a set of recombinant inbred lines (RILs) derived from Milyang 23 (indica)/Tong 88-7 (japonica) crosses in Kunming (high-altitude location), Yanji (high-latitude location), Chuncheon (cold water irrigation), and Suwon (normal) to evaluate the genotypexenvironment (GxE) interactions for chilling tolerance. RILs were the most severely damaged under the natural chilling air temperatures in Kunming. Significant GxE interactions in all measured agronomic traits were detected, and thus, the additive main effects and multiplicative interaction (AMMI) statistical model was applied to dissect the GxE interactions. The biplots of grand mean and IPCA1 (interaction principal component axes) of chilling-related traits accounted for most of the total treatment sums of squares. The IPCA scores of spikelet fertility and phenotypic acceptability were relatively smaller in Chuncheon than in Yanji and Kunming, implying that the screening for chilling tolerance with cold water irrigation in Chuncheon was more stable, whereas the Yanji and Kunming plantings were more sensitive to GxE interactions for chilling tolerance. These results demonstrate that multi-locational screening should be the best strategy for developing widely adaptable chilling-tolerant varieties in rice.

Nuclear structure and β -decay schemes for Te nuclides beyond N=82

Moon, B.,Moon, C.-B.,Sö,derströ,m, P.-A.,Odahara, A.,Lozeva, R.,Hong, B.,Browne, F.,Jung, H. S.,Lee, P.,Lee, C. S.,Yagi, A.,Yuan, C.,Nishimura, S.,Doornenbal, P.,Lorusso, G.,Sumikama, T.,Watan American Physical Society 2017 Physical Review C Vol.95 No.4

<P>We study for the first time the internal structure of Te-140 through the beta-delayed gamma-ray spectroscopy of Sb-140. The very neutron-rich Sb-140 nuclei with Z = 51 and N = 89 were produced by the in-flight fission of U-238 beams at the Radioactive Isotope Beam Factory, RIKEN. The half-life and spin-parity of Sb-140 are reported as 173 +/- 12 ms and 3(-), respectively. In addition to the excited states of Te-140 produced by the beta-decay branch, the beta-delayed one-neutron and two-neutron emission branches were also established. By identifying the first 2(+) and 4(+) excited states of Te-140, we found that Te isotopes persist in their vibrator character with E(4(+))/E(2(+)) = 2. We discuss the distinctive features manifest in this region revealed in pairs of isotopes with the same neutron holes and particles with respect to N = 82.</P>

Role of interfacial interactions on the anomalous swelling of polymer thin films in supercritical carbon dioxide

Li, Yuan,Park, Eun J.,Lim, Kwon T.,Johnston, Keith P.,Green, Peter F. Interscience 2007 Journal of polymer science. Part B, Polymer physic Vol.45 No.11

<P>It has recently been shown that thin polymer films in the nanometer thickness range exhibit anomalous swelling maxima in supercritical CO<SUB>2</SUB> (Sc-Co<SUB>2</SUB>) in the vicinity of the critical point of CO<SUB>2</SUB>. The adsorption isotherm of CO<SUB>2</SUB> on carbon black, silica surfaces, porous zeolites, and other surfaces, is known to exhibit anomalous maxima under similar CO<SUB>2</SUB> conditions. It is believed that because CO<SUB>2</SUB> possesses a low cohesive energy density, there would be an excess amount of CO<SUB>2</SUB> at the surfaces of these materials and hence the CO<SUB>2</SUB>/polymer interface. This might cause excess CO<SUB>2</SUB> in the polymer films near the free surface, and hence the swelling anomaly. In addition, an excess of CO<SUB>2</SUB> would reside at the polymer/substrate and polymer/CO<SUB>2</SUB> interfaces for entropic reasons. These interfacial effects, as have been suggested, should account for an overall excess of CO<SUB>2</SUB> in a thin polymer film compared to the bulk, and would be responsible for the anomalous swelling. In this study, we use in situ spectroscopic ellipsometry to investigate the role of interfaces on the anomalous swelling of polymer thin films of varying initial thicknesses, h<SUB>0</SUB>, exposed to Sc-CO<SUB>2</SUB>. We examined three homopolymers, poly(1,1′-dihydroperflurooctyl methacrylate) (PFOMA), polystyrene (PS), poly(ethylene oxide) (PEO), that exhibit very different interactions with Sc-CO<SUB>2</SUB>, and the diblock copolymer of PS-b-PFOMA. We show that the anomalous swelling cannot be solely explained by the excess adsorption of CO<SUB>2</SUB> at interfaces. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1313–1324, 2007</P>

Ultrafast Pump-Probe Study of Phase Separation and Competing Orders in the Underdoped(Ba,K)Fe2As2Superconductor

Chia, Elbert E. M.,Talbayev, D.,Zhu, Jian-Xin,Yuan, H. Q.,Park, T.,Thompson, J. D.,Panagopoulos, C.,Chen, G. F.,Luo, J. L.,Wang, N. L.,Taylor, A. J. American Physical Society 2010 Physical Review Letters Vol.104 No.2

<P>We report measurements of quasiparticle relaxation dynamics in the high-temperature superconductor (Ba,K)Fe2As2 in optimally doped, underdoped, and undoped regimes. In the underdoped sample, spin-density wave (SDW) order forms at approximately 85 K, followed by superconductivity at approximately 28 K. We find the emergence of a normal-state order that suppresses SDW at a temperature T{*} approximately 60 K and argue that this normal-state order is a precursor to superconductivity.</P>

Effect of Deformation Temperature on Crystal Texture Formation in Hot Deformed Nanocrystalline SmCo₅ Permanent Magnets

Q. Ma,M. Yue,W. C. Lv,H. G. Zhang,X. K. Yuan,D. T. Zhang,X. F. Zhang,J. X. Zhang,X. X. Gao 한국자기학회 2016 Journal of Magnetics Vol.21 No.1

In the present study, bulk anisotropic nanocrystalline SmCo₅ magnets were prepared by hot deformation. The effect of deformation temperature on the texture and magnetic properties are presented, based on which the mechanism of plastic deformation and texture formation during the hot deformation process is discussed. Our analyses reveal that deformation temperature is one of the most important parameters that determine the texture of SmCo5 grains. We suggest that diffusion creep plastic deformation occurs during hot deformation, which is very sensitive to the energy gain provided by an increase in temperature.

Relative humidity-dependent viscosity of secondary organic material from toluene photo-oxidation and possible implications for organic particulate matter over megacities

Song, Mijung,Liu, Pengfei F.,Hanna, Sarah J.,Zaveri, Rahul A.,Potter, Katie,You, Yuan,Martin, Scot T.,Bertram, Allan K. Copernicus GmbH 2016 Atmospheric Chemistry and Physics Vol.16 No.14

<P>Abstract. To improve predictions of air quality, visibility, and climate change, knowledge of the viscosities and diffusion rates within organic particulate matter consisting of secondary organic material (SOM) is required. Most qualitative and quantitative measurements of viscosity and diffusion rates within organic particulate matter have focused on SOM particles generated from biogenic volatile organic compounds (VOCs) such as α-pinene and isoprene. In this study, we quantify the relative humidity (RH)-dependent viscosities at 295 ± 1 K of SOM produced by photo-oxidation of toluene, an anthropogenic VOC. The viscosities of toluene-derived SOM were 2 × 10−1 to ∼ 6 × 106 Pa s from 30 to 90 % RH, and greater than ∼ 2 × 108 Pa s (similar to or greater than the viscosity of tar pitch) for RH ≤ 17 %. These viscosities correspond to Stokes-Einstein-equivalent diffusion coefficients for large organic molecules of ∼ 2 × 10−15 cm2 s−1 for 30 % RH, and lower than ∼ 3 × 10−17 cm2 s−1 for RH ≤ 17 %. Based on these estimated diffusion coefficients, the mixing time of large organic molecules within 200 nm toluene-derived SOM particles is 0.1-5 h for 30 % RH, and higher than ∼ 100 h for RH ≤ 17 %. As a starting point for understanding the mixing times of large organic molecules in organic particulate matter over cities, we applied the mixing times determined for toluene-derived SOM particles to the world's top 15 most populous megacities. If the organic particulate matter in these megacities is similar to the toluene-derived SOM in this study, in Istanbul, Tokyo, Shanghai, and São Paulo, mixing times in organic particulate matter during certain periods of the year may be very short, and the particles may be well-mixed. On the other hand, the mixing times of large organic molecules in organic particulate matter in Beijing, Mexico City, Cairo, and Karachi may be long and the particles may not be well-mixed in the afternoon (15:00-17:00 LT) during certain times of the year. </P>