We theoretically demonstrate the achievement of narrow-band coherent anti-Stokes Raman scattering (CARS) signal by manipulating broad-band probe spectrum. The narrowing of the CARS signal depends on the spectrum bandwidth of the probe beam, and thus high-resolution CARS signal for a complicated quantum system can be obtained by the simple spectrum manipulation. Furthermore, the energy-level diagram for the complicated quantum system can also be labelled by measuring the CARS signal at a given frequency.
ZrxCu100-x amorphous films are prepared on Si (111) substrates by magnetron co-sputtering of pure Zr and Cu. It is found that the glass forming ability (GFA) of the films increases with x when x is in the range from 35 to 65 and with the best glass forming ability at x = 65. It is therefore different from the bulk counterparts, for which only x = 35 and 50 were reported to have high glass forming ability during casting. The structure of the films is sensitive to the substrate temperature and the sputtering argon pressure.
A new (2+1)-dimensional shallow water wave system, the (2+1)-dimensional displacement shallow water wave system (2DDSWWS), is constructed by applying variational principle of the analytic mechanics under the Lagrange coordinates. The general travelling wave solution is expressed as an elliptic integral. A special case is explicitly expressed by the Jacobi elliptic function which is a generalization of the solitary wave solution. Compared with some traditional (2+1)-dimensional shallow water wave systems such as the Kadomtsev Petviashvili (KP) description under the Euler coordinates, the 2DDSWWS has some its own advantages. In addition, the KP equation can also be derived from the 2DDSWWS under the weak two-dimensional long-wave approximation.
Selective excitation of coherent anti-Stokes Raman scattering from the benzene solution is achieved by adaptive pulse shaping based on genetic algorithm, and second harmonic generation frequency-resolved optical gating (SHG-FROG) technique is adopted to characterize the original and optimal laser pulses. The mechanism for two-pulse coherent mode-selective excitation of Raman scattering is experimentally investigated by modulating the pump pulse in the frequency domain, and it is indicated that two-pulse coherent mode-selective excitation of Raman scattering mainly depends on the effective frequency components of the pump pulse related to specific vibrational mode. The experimental results suggest that two-pulse CARS has good signal-to-background ratio and high sensitivity, and it has attractive potential applications in the complicated molecular system.
The rare fossil Miraluolishania described by Liu et al. from the Lower Cambrian Chengjiang Lagersttte in 2004 is regarded as an arthropod sphinx because it bears mosaic features of both lobopods and arthropods. The discovery of this rare transitional form offers direct fossil evidence for exploring the relationship between lobopods and arthropods. However, some scientists consider Miraluolishania to be a junior synonym of Luolishania because the former superficially resembles the latter in general appearance. Considering the significant differences between the two taxa, a thorough comparative study of Miraluolishania and Luolishania leads to the conclusion that there are definitely two different genera. Nevertheless, the "Luolishania" of the Haikou area is indeed "Miraluolishania", whereas Luol-ishania is most likely the typical genus of the Maotianshan area of Chengjiang County.
The effect of yttrium addition on glass formation of a ZrCuAlSi alloy is investigated. The maximum diameter 8mm of the glassy rods for (Zr46.3Cu43.3Al8.9Si1.5)100-xYx alloy with x = 2.5 is obtained by copper mould casting. Apparent enhancement of the glass formation ability is found with addition of yttrium, mainly due to the purification of the alloy melt and the suppression of formation of the primary phases by yttrium.