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On the basis of the supercritical water experimental data, the distribution of onset heat flux is analyzed for the heat transfer deterioration. This study evaluates the performance of empirical correlations for the prediction of heat flux, causing the onset of heat transfer deterioration in vertical tubes of supercritical water. In light of the calculation results, it is shown that the onset of heat transfer deterioration effect is better predicted using the Mokry, Li and Schatte criterion. On the basis of experimental data, a new correlation is developed for predicting the heat flux, which causes the onset of heat transfer deterioration in supercritical water. The new calculation model has considered the influence of mass flux, pipe diameter, pressure and inlet temperature. The newly developed correlation has an average relative error of 0.020837 and an average absolute deviation of 0.1627. The improved criterion is more conducive for the design of supercritical water reactors in the future.

Saturated boiling of two-phase natural circulation has been experimentally investigated based on a natural circulation device with narrow rectangular channels. When heating power reaches a certain range, it is possible to observe the phenomenon of saturated boiling and flow pattern transition in the system. The results show the heat transfer coefficient of saturated boiling decreases with the increasing of pressure, heating power and size of narrow rectangle channels. The buoyancy force causing mixed convection decreases the heat transfer coefficient. Finally, a dimensionless number is introduced, which reflects length to width ratio of rectangular narrow section and Rayleigh number, in order to revise the presented correlation. All errors fall within the range of ±15%.

The time calibration for end cap TOF system of BESIII is studied in this paper. It has achieved about 110 ps time resolution for muons in dimu events. The pulse height correction using electronic scan curve and the predicted time calculated using Kalman filter method are introduced. This paper also describes the study of using electrons and muons as calibration samples.

Mise en evidence de differents regimes de variation vis-a-vis de la temperature de l'effet magneto-optique de Faraday dans un milieu paramagnetique. Si le champ applique n'est pas tres eleve, le rapport constant de Verdet/susceptibilite est V/x=A (1+BT) dans certains milieux, ou V/x=A(1+B/T) dans d'autres. On montre que les parties reelles O' et imaginaire O″ de la rotation de Faraday sont proportionnelles au champ effectif Hi

Based on density functional first-principles calculations, we study the stability, micro-geometry, and electronic properties of alkali metal atoms adsorbed on silicene, and perform the comparison between pure and hydrogen-saturated silicenes. We found that all the formation energies of SiX(X=Li, Na, K and Rb) are negative, indicating that the relative structural stability of these new compounds is higher than silicene. Bader charge analysis shows that electric charge is transferred from Si atoms to H atoms in SiH compound, but in SiX the direction of charge transfer is opposite, i.e., the charge is transferred from alkali metal atoms to Si atoms. From the viewpoint of chemical bonding, it can be regarded that valence bond is formed between Si atoms and H atoms, and the bonds between Si and alkali metal atoms are mainly ionic, but there exists covalent contribution. From the band structure calculations, it is also found that the new type compound SiLi is a semiconductor with a direct band gap of 0.34 eV; however, all the other compounds of SiX(X=Na, K and Rb) exhibit metallic property.

According to density functional first-principles calculations, we study the substitutional doping of Co atoms in core-shell silicon nanowires. By comparing the formation energies, we find that all the doping configurations obtained from shell-chain doping, core doping, and whole shell doping are stable, and core-shell doping silicon nanowire has the highest structural stability. All the doped configurations show metallic property, and the conductance channels increase with the increasing of doping concentration. Co-doped silicon nanowires show ferromagnetic, possessing magnetic moment. Bader charge analysis shows that charge is transferred from Si atoms to Co atoms in doped silicon nanowires. In transition metal Co atom, charge is transferred from 4s orbital to 3d and 4p orbital. The reducing of unpaired electron in 3d orbital and part of charge transferring from up-spin to down-spin in 4s, 3d and 4p orbital, makes magnetic moments in Co atom reduced.

A method to determine three-dimensional refractive index profile of holey fiber using a combination of quantitative phase microscopy and tomographic reconstruction techniques is described. Results show that the method based on the transport-of-intensity equation for phase retrieval is straightforward to measure phase profile, nondestructive to the measured fiber, and valuable to determine three-dimensional refractive index profile of holey fiber.

To investigate the biological function of F protein by yeast two-hybrid system.We constructed F protein bait plasmid by cloning the gene of F protein into pGBKT7, then recombinant plasmid DNA was transformed into yeast AH109 (a type). The transformed yeast AH109 was mated with yeast Y187 (alpha type) containing liver cDNA library plasmid in 2XYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing X-alpha-gal for selection and screening. After extracting and sequencing plasmids from positive (blue) colonies, we underwent sequence analysis by bioinformatics.Thirty-six colonies were selected and sequenced. Among them, 11 colonies were zymogen granule protein, 5 colonies were zinc finger protein, 4 colonies were zinc-alpha-2-glycoprotein, 1 colony was sialyltransferase, 1 colony was complement control protein factor I, 1 colony was vitronectin, and 2 colonies were new genes with unknown function.The yeast two-hybrid system is an effective method for identifying hepatocyte proteins interacting with F protein of hepatitis C virus. F protein may bind to different proteins.

In some paramagnetic media, the effective field Hi which includes exchange interaction and external magnetic field, can cause the splitting of ground state energy level. In the region of the temprature T>Tc, the Curie temperature, there is certain probability distribution of electrons on two energy levels arised from ground state splitting. This induces the ground state energe level for double transition. It is proved by calculation according to this theory, there are several temperature characteristics for magneto-optical Faraday effect of the paramagnetic media. With the external magnetic field not too high, the ratio of the Verdet constant to magnetic susceptibility x is V/x = A(1+BT) in some media, or V/x = A(1 + B/T) in other media. It is also showed that both the real part θ′ and the imaginary part θ" of Faraday rotation are proportional to the effective field Hi, and with similar temperature character beyond the range of optical absorption.