Thermal Fatigue Resistance of Bionic Compacted Graphite Cast Iron Treated with the Twice Laser Process in Water

For enhancing the thermal fatigue resistance of bionic compacted graphite cast iron (CGI) lasertreated in water, the bionic units are treated twice with the laser to form an uneven bionic surface imitating the alternately soft and hard structure of a plant leaf, which can resist the tearing wind. The results show that this method, without changing the phase composition of the bionic unit, makes the austenite-to-martensite transformation more complete and the content of residual austenite is reduced, in addition, the microstructure coarsens and microhardness slightly turns lower. The twice laser process in water can effectively enhance the thermal fatigue resistance of bionic CGI by reducing the number of cracks in bionic units since the number of cross cracks on the bionic unit surface is the key factor, which affects their resistance to thermal crack propagation.For enhancing the thermal fatigue resistance of bionic compacted graphite cast iron (CGI) lasertreated in water, the bionic units are treated twice with the laser to form an uneven bionic surface imitating the alternately soft and hard structure of a plant leaf, which can resist the tearing wind. The results show that this method, without changing the phase composition of the bionic unit, makes the austenite-to-martensite transformation more complete and the content of residual austenite is reduced, in addition, the microstructure coarsens and microhardness slightly turns lower. The twice laser process in water can effectively enhance the thermal fatigue resistance of bionic CGI by reducing the number of cracks in bionic units since the number of cross cracks on the bionic unit surface is the key factor, which affects their resistance to thermal crack propagation

Spin-orbit coupling in bulk GaAs

We study the spin-orbit coupling in the whole Brillouin zone for GaAs using both the $sp^3s^{\ast}d^5$ and $sp^3s^{\ast}$ nearest-neighbor tight-binding models. In the $\Gamma$-valley, the spin splitting obtained is in good agreement with experimental data. We then further explicitly present the coefficients of the spin splitting in GaAs $L$ and $X$ valleys. These results are important to the realization of spintronic device and the investigation of spin dynamics far away from equilibrium.Comment: 8 pages, 3 figures, Physica E, in pres

Synthesis and pinning properties of the infinite-layer superconductor Sr0.9La0.1CuO

We report the high-pressure synthesis of the electron-doped infinite-layer superconductor Sr0.9La0.1CuO2 and its superconducting properties. A Rietveld analysis of X-ray powder diffraction data showed that, within the resolution of the measurement, the sample had purely an infinite-layer structure without any discernible impurities. The superconducting volume fraction and the transition width were greatly improved compared to those in previous reports. The irreversibility field line and the intragranular critical current density were much higher than those of La1.85Sr0.15CuO4 and Nd1.85Ce0.15CuO4. The stronger pinning behaviors are consistent with the strong interlayer coupling due to the short distance between CuO2 planes.Comment: Physica C (in press) 5 pages, 4 figur

Boty-II, a novel LTR retrotransposon in Botrytis cinerea B05.10 revealed by genomic sequence

Botrytis cinerea is a necrotrophic pathogen causing pre- and post-harvest diseases in at least 235 plant species. It manifests extraordinary genotype and phenotype variation. One of the causes of this variation is transposable elements. Two transposable elements have been discovered in this fungus, the retrotransposon (Boty), and the transposon (Flipper). In this work, two complete (Boty-II-76 and Boty-II-103) and two partial (Boty-II-95 and Boty-II-141) long terminal repeat (LTR) retrotransposons were identified by an in silico genomic sequence analysis. Boty-II-76 and Boty-II-103 contain 6439 bp nucleotides with a pair of LTRs at both ends, and an internal deduced pol gene encoding a polyprotein with reverse transcriptase and DDE integrase domains. They are flanked by 5 bp direct repeats (ACCAT, CTTTC). In Boty-II-141, two LTRs at both ends, and a partial internal pol gene encoding a protein with a DDE integrase domain were identified. In Boty-II-95, a right LTR and a partial internal pol gene encoding a protein with no conserved domains were identified. Boty-II uses a self-priming mechanism to initiate synthesis of reverse transcripts. The sequence of the presumed primer binding site for first-strand reverse transcription is 5'-TTGTACCAT-3'. The polypurine-rich sequence for plus-strand DNA synthesis is 5'-GCCTTGAGCGGGGGGTAC-3'. Fourteen Boty-II LTRs that contain 125-158 bp nucleotides and share 69.1 ~ 100% identities with the short inverted terminal repeats of 5 bp (TGTCA\u2026TGACA) were discovered. Analysis of structural features and phylogeny revealed that Boty-II is a novel LTR retrotransposon. It could potentially be used as a novel molecular marker for the investigation of genetic variation in B. cinerea

Application of spherical harmonics analysis on LBS particles and LBS fragments

This paper applies surface parameterization and spherical harmonics analysis to the characterization of particle shapes of Leighton Buzzard sand (LBS) particles and LBS fragments obtained from X-ray micro-tomography (μCT). The rotation, transition and scale independent spherical coefficients were obtained. The relationship between spherical coefficients and shape parameters of form, roundness and compactness was investigated. The coefficients of degree one determine the principal dimensions of an ellipsoid, which has a similar aspect ratio with the original surface. The coefficients of higher degree characterise more details by increasing the percentage of higher and lower mean curvature on the reconstructed surface. As the spherical degree increases, the reconstructed surface tend to have lower particle roundness, sphericity and convexity, and higher aspect ratio

First long-term study of particle number size distributions and new particle formation events of regional aerosol in the North China Plain

Atmospheric particle number size distributions (size range 0.003–10 μm) were measured between March 2008 and August 2009 at Shangdianzi (SDZ), a rural research station in the North China Plain. These measurements were made in an attempt to better characterize the tropospheric background aerosol in Northern China. The mean particle number concentrations of the total particle, as well as the nucleation, Aitken, accumulation and coarse mode were determined to be 1.2 ± 0.9 × 104, 3.6 ± 7.9 × 103, 4.4 ± 3.4 × 103, 3.5 ± 2.8 × 103 and 2 ± 3 cm−3, respectively. A general finding was that the particle number concentration was higher during spring compared to the other seasons. The air mass origin had an important effect on the particle number concentration and new particle formation events. Air masses from northwest (i.e. inner Asia) favored the new particle formation events, while air masses from southeast showed the highest particle mass concentration. Significant diurnal variations in particle number were observed, which could be linked to new particle formation events, i.e. gas-to-particle conversion. During particle formation events, the number concentration of the nucleation mode rose up to maximum value of 104 cm−3. New particle formation events were observed on 36% of the effective measurement days. The formation rate ranged from 0.7 to 72.7 cm−3 s−1, with a mean value of 8.0 cm−3 s−1. The value of the nucleation mode growth rate was in the range of 0.3–14.5 nm h−1, with a mean value of 4.3 nm h−1. It was an essential observation that on many occasions the nucleation mode was able to grow into the size of cloud condensation nuclei (CCN) within a matter of several hours. Furthermore, the new particle formation was regularly followed by a measurable increase in particle mass concentration and extinction coefficient, indicative of a high abundance of condensable vapors in the atmosphere under study