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The 2175 �� ultraviolet (UV) extinction bump in interstellar medium (ISM) of the Milky Way was discovered in 1965. After intensive exploration of more than a half century, however, its exact origin still remains a big conundrum that is being debated. Here we propose a mixture model by which the extinction bump in ISM is argued possibly relevant to the clusters of hydrogenated T-carbon (HTC) molecules (C40H16) that have intrinsically a sharp absorption peak at the wavelength 2175 ��. By linearly combining the calculated absorption spectra of HTC mixtures, graphite, MgSiO3 and Fe2SiO4, we show that the UV extinction curves of optional six stars can be nicely fitted. This present work poses an alternative explanation toward understanding the physical origin of the 2175 �� extinction bump in ISM of the Milky Way., Monthly Notices of the Royal Astronomical Society accepted

For multi-view viewpoint planning research, Firstly, using the UAV aerial multi-view image, the viewpoint view is first to establish a candidate view area according to the shooting distance. Secondly, the sub-viewpoint set is filtered and the view points are complemented by the region where the candidate view cannot be photographed, so that the three-dimensional reconstruction data has better integrity. Thirdly, the influence of camera incident angle on image pixel error is analyzed, and the corresponding 3D model is established. Finally, the stereoscopic overlap is used to perform viewpoint screening under the premise of ensuring image quality and shooting coverage. The experimental results show that the proposed viewpoint planning method has high coverage and the reconstruction accuracy is below 0.1% of the target size.

Amorphous Er2O3 films are deposited on Si (001) substrates by using reactive evaporation. This paper reports the evolution of the structure, morphology and electrical characteristics with annealing temperatures in an oxygen ambience. X-ray diffraction and high resolution transimission electron microscopy measurement show that the films remain amorphous even after annealing at 700 °C. The capacitance in the accumulation region of Er2O3 films annealed at 450 °C is higher than that of as-deposited films and films annealed at other temperatures. An Er2O3/ErOx/SiOx/Si structure model is proposed to explain the results. The annealed films also exhibit a low leakage current density (around 1.38 × 10−4 A/cm2 at a bias of −1 V) due to the evolution of morphology and composition of the films after they are annealed.

Er2O3 thin films are grown on oxidized Si (111) substrates by molecular beam epitaxy. The sample grown under optimized condition is characterized in its microstructure, surface morphology and thickness using grazing incidence x-ray diffraction (GIXRD), atomic force morphology and x-ray reflectivity. GIXRD measurements reveal that the Er2O3 thin film is a mosaic of single-crystal domains. The interplanar spacing d in-plane residual strain tensor e∥ and the strain relaxation degree ξ are calculated. The Poisson ratio μ obtained by conventional x-ray diffraction is in good agreement with that of the bulk Er2O3. In-plane strains in three sets of planes, i.e. (440), (404), and (044), are isotropic.

We study the news system and explore news report mechanism based on the corpus of Sina news website. Instead of using complete content of news, we utilize short keywords to represent original news and mainly focus on the report time series of news. Empirical analysis shows that the distributions of time intervals follow power-law distribution with exponential cutoff on both single-class level and aggregate level. In addition, we analyze the vitality of keywords to explain why the distributions of different kinds of news show difference in the exponential cutoff tail. On the basis of these findings, we propose a hybrid mechanism queuing model to reveal the hidden principle of news reports. The simulation results can well fit the empirical data. The present study may shed some light on the mechanism of temporal patterns of news report and human selection behaviors.

Since 2002, whether existing bubbles in Chinese real estate market has been a controversial question. On the one hand, the real estate management organs and enterprises deny the bubble's existence. And on the other hand, all consumers consider that there has big bubble in real estate market based on soaring real estate price nowadays. Scholars in economics also have different opinions on this theme. The paper tests the stationarity of real estate's market price time series and theoretical price time series and the conintegration relationship between the two series of Chinese 35 main cities, include 30 provincial capitals except for Lasa City and 5 cities of planning individually (Dalian, Qingdao, Shenzhen, Ningbo, Xiamen), by the method of unit root and cointegration test. And the test results show that bubbles exist in all of other cities' real estate market except for Taiyuan City, that is to say, the existence of urban real estate market bubbles is a general phenomena in China. If analyzing from the change trend of real estate market price latest months, we find that only few cities' market price, such as Shenzhen etc., has decreasing trend and almost all cities' market price still increase steadily, which provides an evidence that real estate market bubbles of most big and middle scale cities will keep on a period of time. The paper suggests that Chinese government and real estate industrial organs should emphasize macroeconomic control and management, and lead consumers and investors correctly, to offer a good micro and macroeconomic environment of real estate market; at the same time, the government should perfect data statistic system and information release system so that to offer a good condition for analyzing and alarming real estate market problem

According to refractive indexes of nanomaterials （less than 1.4） and the AM0 solar spectrum, antireflection coatings of space Si solar cells are designed and analyzed. For double-layer and tri-layer antireflection coatings fabricated by normal and nanometer materials, the optimal parameters of coatings and reflection coefficient curves are obtained. The double-layer and tri-layer new nano antireflection coatings are optimized, and have better antireflection compared with those fabricated using the normal materials. It is interesting that, after optimizing, the minimal weighted reflectance of the new nano antireflection coatings is 15% and 24.5% less than that of the normal antireflection coatings for the double-layers and the tri-layers, respectively.