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A photovoltaic effect is observed in the heterostructure of p-Si∕n-SrTiO3−δ (p: hole carrier type, n: electron carrier type). The current–voltage curve exhibits a good rectifying characteristic similar to that of the traditional diode. The junction shows the open circuit voltage of 126mV∕mJ, the short circuit current of 1.78mA∕mJ, and the response time faster than 10ns for ultraviolet pulsed laser of 25ns in duration at room temperature, suggesting the promising potential of this junction as a new type of ultrafast ultraviolet detectors with high sensitivity for application.

Coal property and structures of 32 kinds of Chinese coals were investigated from the insights of second-order Raman spectrum using micro-Raman spectroscopy. A new deconvolution method for the second-order Raman spectrum of coal has been established, and the spectrum from 2100 to 3400 cm −1 was curve-fitted by eight Gaussian bands successfully. The results indicate that the bands at 3060 and 2810 cm −1 are sensitive to the volatiles content in coal and the bands at 2925, 2670, and 2480 cm −1 are related to the more ordered structures of coal. Reasonable correlations between the second-order Raman bands area ratios and coal property parameters have been found, and an effectively comprehensive method for evaluating the coal property based on a second-order Raman spectrum has been built. The results reveal that the C−H and amorphous carbon structures increase with the increase of volatile content in the coal but have no obvious relationship with the fixed carbon content. Besides, the order degree of coal structure has a good positive correlation with the ratio of fixed carbon to volatiles content in the coal. This study demonstrates that the second-order Raman spectrum can reveal useful structure information on coal and provide a new approach for evaluating coal properties.

Ordered self-organized complex oxide Ce:BaTiO3 quantum dots shaped as a pyramid with a square base were fabricated by pulsed laser deposition. The density of the quantum dots was about 140 μm−2. The nonlinear optical properties were determined by the single beam Z scan method at a wavelength of 0.532 μm with a laser duration of 10 ns. The nonlinear refractive indices of the wetting layer and the self-organized ordered quantum dots were 8.87×10−8 and 6.39×10−7 esu, respectively. The mechanisms of the nonlinear effect enhancement for these low-dimensional structures are discussed.

The concept of “high entropy” was first proposed while exploring the unknown center of the metal alloy phase diagram, and then expanded to oxides. The colossal dielectric constant found on the bulk high-entropy oxides (HEOs) reveals the potential application of the high-entropy oxides in the dielectric aspects. Despite the fact that known HEO thin films have not been reported in the field of dielectric properties so far, with the high-entropy effects and theoretical guidance of high entropy, it is predictable that they will be discovered. Currently, researchers are verifying that appropriately increasing the oxygen content in the oxide, raising the temperature and raising the pressure during preparation have an obvious influence on thin films’ resistivity, which may be the guidance on obtaining an HEO film large dielectric constant. Finally, it could composite a metal–insulator–metal capacitor, and contribute to sensors and energy storage devices’ development; alternatively, it could be put into application in emerging thin-film transistor technologies, such as those based on amorphous metal oxide semiconductors, semiconducting carbon nanotubes, and organic semiconductors.

The specific binding between Cy5-labeled goat anti-mouse Immunoglobulin G (IgG) and mouse IgG with a concentration range from 625 to 10 4 μg ml −1 has been detected successfully by the oblique-incidence reflectivity difference (OI-RD) method in each procedure of microarray fabrication. The experimental data prove that the OI-RD method can be employed not only to distinguish the different concentrations in label-free fashion but also to detect the antibody-antigen capture. In addition, the differential treatment of the OI-RD signals can decrease the negative influences of glass slide as the microarray upholder. Therefore the OI-RD technique has promising applications for the label-free and high-throughput detection of protein microarrays.

The aim of this study is to investigate the changes in iron phase, crystal size, surface area, and char structure/reactivity of the char-supported iron catalysts after them being used for bio-oil reforming. The catalysts were prepared under different conditions (varying in temperatures, gasification agents and iron concentrations) and then used to reform bio-oil under a fixed experimental condition at 800 °C. The results show that the catalysts prepared from the steam gasification of Fe-loaded coal were preferred in terms of catalytic performance. The X-ray diffraction analysis indicates that the iron phases in the fresh catalysts varied while the used catalysts nearly showed identical iron phase of magnetite (Fe 3 O 4). The crystal iron particle in the catalysts would apparently increase after reforming when the initial iron phase was carbides (γ-Fe and/or α-Fe). The char structure of the catalysts was significantly affected by the "volatile-char interactions" during reforming process. And the catalysts" surface area and reactivity in air were both reduced mainly due to the coke formation.