In this work, the effects of different preparation methods on the microstructures and properties of the Ti45.7Zr33Ni3Cu5.8Be12.5 alloy were systematically studied by both experimental and numerical ways. It is found that the heating methods and the cooling rate during the process of preparation have great influences not only on the morphology and crystalline structure of the solid solutions but also on the thermal stability of the amorphous phase. Furthermore, the different crystalline structures and micromorphologies of the ductile phase will also influence the mechanical properties. And the uniaxial compression tests at room temperature verify that the Ti45.7Zr33Ni3Cu5.8Be12.5 samples obtained by different preparation methods possess different degrees of plasticity. The better comprehensive properties were found for samples with a larger size under the copper mold cooling conditions. The variation of the morphology of the solid solution phase under different preparation conditions is believed to be the vital factor that leads to the diversity in properties.

In the present study, the internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of Oesophagostomum asperum and O. columbianum were amplified and sequenced. The ITS-1, 5.8S and ITS-2 rDNA sequences of O. asperum were 374 bp, 153 bp and 259 bp in length, respectively, and the corresponding sequences of O. columbianum were 259, 153 and 218 bp in length, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA between the two Oesophagostomum species were 9.5–10.2% and 12.7–13.9%, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA among members of the genus Oesophagostomum were 2.5–11.6% and 6.8–22.3%, respectively. Based on genetic markers in the ITS rDNA, an effective polymerase chain reaction (PCR) approach was developed to differentiate O. columbianum from O. asperum with a sensitivity of 0.2 ng/μl DNA. Since accurate characterization of parasites at different taxonomic levels is essential for population genetic studies and control of parasitosis, the present findings have important implications for studying epidemiology, taxonomy and population biology, as well as for the control of oesophagostomiasis.

The influence of the surface roughness of Ag/ZnO coated substrates on the AM1.5 J-V characteristics of microcrystalline silicon (μc-Si:H) solar cells with an i-layer made by the hot-wire chemical vapour deposition (HWCVD) technique is discussed. Cells deposited on substrates with an intermediate rms roughness show the highest efficiency. When using reverse hydrogen profiling during i-layer deposition, an efficiency of 8.5 % was reached for single junction μc-Si:H n-i-p cells, which is the highest for μc-Si:H n-i-p cells with a hot-wire i-layer.

In this paper, the potential of hot-wire chemical vapor-deposited (HWCVD) microcrystalline silicon (μc-Si) for use in solar cells is explored. Incorporation of the material in the current-limiting bottom cell of two tandem cells on plain stainless steel resulted in FF values as high as 0.77, which is much higher than the highest single junction FF. A combination of experiments, calculations and computer simulations was employed to identify causes for the observed high tandem cell FF values. Both the light intensity and the spectral composition of the bottom cell illumination in a tandem were found to contribute to an increase of the bottom cell FF. The fact that the operational voltage of a tandem cell is higher than that of the current-limiting subcell, was calculated to lead to a tandem FF that can be far higher than that of the limiting cell. Com-puter simulations with the AMPS computer code show that the current mismatch in a tandem cell reduces the recombination in the current-limiting cell, possibly by slightly enhancing the internal field of that cell. Use of a 1.5 μm ìc-Si:H hot-wire deposited absorber layer in a single junction cell on a textured back reflector yielded a Voc, FF and Jsc of 0.543 V, 0.656 and 23.60 mA/cm2, respectively, which combine to an 8.4 % record efficiency for μc-Si single junction n-i-p cells with a hot-wire intrinsic layer.

Epitaxial lanthanum zirconate (LZO) buffer layers have been grown by sol-gel processing on Ni–W substrates. We report on the application of these oxide films as seed and barrier layers in coated conductor fabrication as potentially simpler, lower cost coated-conductor architecture. The LZO films, about 80–100-nm thick, were found to have dense, crack-free surfaces with high surface crystallinity. Using 0.2-μm YBCO deposited by pulsed laser deposition, a critical current density of 2 MA/cm2 has been demonstrated on the LZO films (YBCO/LZO/Ni–W). Using 0.8-μm YBCO deposited using metal organic decomposition, a critical current density of 1.7 MA/cm2 and a critical current of 135 A/cm have been demonstrated on the LZO barrier layer with a sputtered CeO2 cap layer (YBCO/CeO2/LZO/Ni–W). These results offer promise to replace several of the vacuum-deposited layers in the typical coated conductor architecture (YBCO/CeO2/YSZ/Y2O3/Ni/Ni-W).

Metal-insulator-semiconductor structures are fabricated by depositing SiO2 films on an MOCVD-grown n-type GaN epitaxial layer and a GaN/Al0.4Ga0.6N/GaN double heterojunction. The SiO2 films are grown by plasma-enhanced chemical vapor deposition. High-frequency C-V characteristics show the agreement of the measured C-V curve of SiO2/n-GaN with an ideal curve in deep depletion and the very small hysteresis, which indicates that the interface traps concentration in the sample is low. However, for SiO2/GaN/Al0.4Ga0.6N/GaN, the measured C-V curves show a notable flat-band shift of about 9.2 V and a typical polarization hysteresis window. These show the influence of the polarization charges in this structure. The capacitance on SiO2/GaN/Al0.4Ga0.6N/GaN reaches a minimum value under around –5V bias. The saturation at a minimum value of the C-V curve indicates the presence of holes accumulation in the MIS structure. These results imply that the piezoelectric effect in GaN/Al0.4Ga0.6N/GaN play an important role for the formation of the p-channel.

Low temperature photoluminescence measurements were carried out on pseudomorphically strained InxGa1−xAs-Al0.28Ga0.72As ternary-on-ternary heterostructures grown by molecular beam epitaxy to investigate the change in the transition energy, linewidth, and intensity as a function of InGaAs well thickness at two different indium compositions, x = 0.10 and x = 0.15, respectively. Sharp exciton peaks as narrow as 4-6 meV were observed from the InGaAs wells grown at 530 °C with 1 min of growth interruption at the top and bottom heterointerfaces. The linewidth decreases as the well thickness is increased up to 300 Å. In addition, there are signs of linewidth broadening and sharp decrease in the photoluminescence intensity at higher well thicknesses that may indicate the onset of plastic relaxation. Relatively small variations in the transition energy were observed at well thicknesses that are up to ≍3 times the theoretical critical layer thickness calculated by the Matthews-Blakeslee model,10 suggesting that the small density of dislocations that may be present may not have a significant effect on the band structure of the well.

Low-temperature photoluminescence measurements have been taken to monitor the changes in the properties of strained GaAs/InGaAs/GaAs quantum wells grown by molecular beam epitaxy at different substrate (well) temperatures with and without a 90 s-growth-interruption at the heterointerfaces. Sharp exciton peaks with average linewidths as low as 1.7 meV were observed in all the spectra. The spectra from the samples grown employing interrupts were narrower than those without interrupts, indicating structurally improved interfaces. Further linewidth narrowing was also seen in samples employing an additional interrupt of the same duration at the bottom InGaAs/GaAs interface, or by increasing the interrupt time at the top GaAs/InGaAs interface to 180 s. A consistent reduction in the linewidth was also observed in wells grown at higher temperatures. This is most likely due to greater indium re-evaporation leading to a reduction in strain, well width, and interface fluctuations.