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This paper firstly presents the field tests of a straight and a curved composite continuous box girder bridges. Elaborate FE model and beam FE model are then built on the basis of achievements of the companion paper. According to the comparison of results among elaborate FE model, beam FE model and field test, testing coefficient of mid-span deflection is 0.5~0.8, and that of stress is 0.6~0.9 for the elaborate FE model. Also good correlation of the calculation results between elaborate FE model and beam FE model can be observed with the relative errors within the range of ±10%. This and the companion paper propose the beam-truss model of composite box-girder bridges, then accuracy and adaptability are fully verified by amounts of numerical analysis. Conclusions drawn in these papers are helpful for design analysis of steel-concrete composite box-girder bridge.

A high-performance positron age-momentum correlation (AMOC) spectrometer was newly devel- oped. The counting rate is increased up to 200 cps much larger than the value 20 cps reported by other international groups. And at the same time, the time resolution still keeps at the international level of 2...

We study the structural defects in the SiOx film prepared by electron cyclotron resonance plasma chemical vapour deposition and annealing recovery evolution. The photoluminescence property is observed in the as-deposited and annealed samples. [-SiO3](2-) defects are the luminescence centres of the ultraviolet photoluminescence (PL) from the Fourier transform infrared spectroscopy and PL measurements. [-SiO3](2-) is observed by positron annihilation spectroscopy, and this defect can make the S parameters increase. After 1000 degrees C annealing, [-SiO3](2-) defects still exist in the films.

Helium-containing Ti films are prepared using magnetron sputtering in the helium–argon atmosphere. Isochronal annealing at different temperatures for an hour is employed to reveal the behaviour of helium bubble growth. Ion beam analysis is used to measure the retained helium content. Helium can release largely when annealing above 970 K. A thermal helium desorption spectroscopy system is constructed for assessment of the evolution of helium bubbles in the annealed samples by linear heating (0.4 K/s) from room temperature to 1500 K. Also, Doppler broadening measurements of positron annihilation radiation spectrum are performed by using changeable energy positron beam. Bubble coarsening evolves gradually below 680 K, migration and coalescence of small bubbles dominates in the range of 680–970 K, and the Ostwald ripening mechanism enlarges the bubbles with a massive release above 970 K.

Lower hybrid heating (LHH) has been successfully carried out in the HT-6M tokamak. The H-mode has been obtained with a power threshold of 50 kW under a boronized wall condition. Both energy and particle confinements have been improved along with a dropped edge plasma density and an increase electron temperature during the LHH phase. A negative Er well plays a key role of triggering and sustaining the good confinement. Both electrostatic fluctuation of the plasma potential and the density fluctuations dropped to an ultra-low level. The observation of an enhanced Er shear before the reduction in turbulence level is consistent with an increased Er shear as the cause of turbulence suppression.

Tomographic reconstructions of soft x-ray emissivity in the HT-7 tokamak have been obtained using 86 miniature soft-x-ray detectors. Because there are two-detector arrays which are distributed in horizontal and vertical directions on one poloidal plane, two-dimensional images of x-ray emissivity are obtained without having resort to a rotational model. The algorithm of Fourier-Bessel expansion was employed. The data analysed so far have been used principally to study MHD instabilities, and the illustrative examples of the sawtooth crash in IBW-heated plasma are described.

In this paper the control system of the pellet injector is introduced in detail and the system mainly includes two parts: The present and the remote control system. The present control system controls the injector and provides the interface to the remote system. And the remote control system has acquired present signals with analog input card and perform the actions through digit output card, it also has an interface for Windows programming easily used by the operators when carrying out the pellet injection experiments. Through several HT-7 campaigns, the remote control system has been validated to be feasible and reliable and has made successful shots for studying the interactions between the pellets and plasma.

For the intermetallic compound TiAl, the interatomic potentials in the Finnis-Sinclair model were constructed by empirically fitting to the properties of L10 TiAl tetragonal phase and the pressure-volume relations. In the calculations of the point defect properties of the TiAl alloy with this potential, it was shown that the thermal concentration of anti-site defects was higher than that of other point defects. With similar formation energies, five possible interstitial configurations were stable. This model was consistent with the embedded atom method or embedded defect method and adequate for simulation of defects in the TiAl alloy.

Efficient direct heating of electrons by ion Bernstein waves has been obtained on the HT-7 tokamak. Off-axis heating, which is considered to be the result of electron Landau damping, was observed and studied by means of soft x-ray imaging. The measured power deposition was found to be independent of magnetic field through scanning the toroidal field from 1.5 to 1.7 T, in contrast to the ion heating results. It is suggested that the electron Landau damping is dominant in this heating regime.

Various helium-containing titanium films were deposited on Si substrates by magnetron sputtering under different helium/argon (He/Ar) ambiances. Helium concentrations and corresponding depth profiles in the Ti films are obtained by elastic recoil detection analysis (ERDA). X-ray diffraction (XRD) measurements are carried out to evaluate the crystallization of the titanium films. Vacancy-type defects and their depth profiles were revealed by slow positron beam analysis (SPBA). It is found that the defect-characteristic parameter S rises with the increment of the He/Ar flow ratios. The variation of.. indicates the formation and evolution of various He-related defects, with uniform distribution into the depth around 400 nm.

Helium-containing titanium films were prepared on Si substrates with various biases applied by magnetron sputtering under stable He/Ar ambiance. Rutherford backscattering and elastic recoil detection analyses are used to measure the thickness of the He-Ti films and the helium depth profile, respectively. Experiments of x-ray diffraction and variable energy positron annihilation spectroscopy are carried out to investigate the microstructures of titanium films and the corresponding helium-related defects developed. The behavior of the implanted He, the microstructure of the He-Ti film and the formation of He-related defects all are affected by the substrate biases applied.

Cyanate ester (CE) resin was blended with epoxy resin (EP) at different mass ratios (CE/EP: 100/0, 90/10, 70/30, 50/50, 30/70, 10/90, 0/100). The free volume size of CE/EP IPNs has been determined by positron annihilation lifetime spectroscopy (PALS). The size decreased as the epoxy resin content increased. The PALS results are consistent with the chemical structure changes for the copolymerizing between CE and EP. The crosslinking units of curing products (oxazoline, oxazolidinone, and polyether network) of the blends are all smaller in size than those of triazine ring structure from neat CE. Therefore, the free volume size of the blends decreases with increase of EP content. Examination of the mechanical properties, thermal stability, and morphology of the blend systems showed that addition of epoxy resin resulted in improved toughness but a little sacrifice in thermal stability when compared with pure CE. The correlations between the free volume properties and physical properties (thermal stability and mechanical properties) have been discussed.

Si-rich SiO2 films prepared by rf magnetron co-sputtering method are studied by slow positron beams. The negatively charge point defects (probably Pb centres or peroxy radicals) at the silicon nanocluster (nc-Si)/SiO2 interface are observed by Doppler broadening spectra. Coincidence Doppler-broadening spectra show that positrons have a higher annihilation probability with core electrons nearby oxygen atoms than silicon atoms. The formation of N-related bonds may be the reason for the prevention of the migration reaction of Si and O atoms, hence nc-Si formation is inhibited by annealing in nitrogen compared to in vacuum.