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The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) is an important viral structural protein. Based on bioinformatics analysis, 10 antigenic peptides derived from the S protein sequence were selected and synthesized. The antigenicity and immunoreactivity of all the peptides were tested in vivo and in vitro. Four peptides (P6, P8, P9 and P10) which contain B cell epitopes of the S protein were identified, and P8 peptide was confirmed in vivo to have a potential in serological diagnosis. By using a syncytia formation model, we tested the neutralization ability of all 10 peptides and their corresponding antibodies. It is interesting to find that P8 and P9 peptides inhibited syncytia formation, suggesting that the P8 and P9 spanning regions may provide a good target for anti-SARS-CoV drug design. Our data suggest that we have identified peptides derived from the S protein of SARS-CoV, which are useful for SARS treatment and diagnosis.

The zirconia-doped mullite fibers were prepared via a sol-gel method from aluminum isopropoxide-aluminum nitrate-tetraethyl orthosilicate system. The effects of zirconia doping on the sol spinnability, mullitization, structure and thermal stability of mullite fibers were investigated by means of Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that Zr—O—C bond was presented with the involvement of zirconium acetate, which accelerated the gelation process of the precursor sol. The mullitization process of the doped fibers was promoted by the formation of less middle-phase residues such as spinel. Among the samples investigated, the 1% ZrO2-doped fibers exhibited the highest thermal stability with a grain growth rate of 11% (from 1 000 °C to 1 300 °C), which is only a half of that for pure mullite fibers.

Strain-controlled low cycle fatigue tests were performed for various test-piece geometries, frequencies, CTOD ratios and strain ranges in order to find out the behaviors of fatigue crack growth on pressure vessel steel. The influences of cyclic material properties and deformation rates on da/dN were discussed. The possibility of taking the parameter Δ CTOD ( Δδ t ) as the basis for describing strain-controlled low cycle fatigue behaviors was examined. A specially designed High Strain Tension specimen (HST) was used to simulate high-strain fields in pressure vessels and Compact Tension specimens (CT) were also tested. The relationship between da/dN and Δ CTOD was obtained from the results of two types of specimen.

A numerical analysis of a four‐electrode electrostatic mirror is presented. The results indicate that this mirror provides correct aberrations as a corrector for electron optical systems and unlike all other mirror configurations known to date, this new system shows for the first time that an adjustable mirror, both in magnitude of the aberration coefficients and in the ratio of CS/Cc, can indeed be found in a practical system.