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In this study, the epitaxial growth of the full-composition-graded AlxGa1-xN films has been demonstrated on the sapphire substrates by using metalorganic chemical vapor deposition (MOCVD). The aluminum composition in the AlxGa1-xN films has been precisely controlled from 0 to 100%, as confirmed by X-ray diffraction and energy-dispersive spectroscopy analyses. The pseudo-periodic AlxGa1-xN/AlyGa1-yN structures are spontaneously formed during the initial growth of the graded AlGaN layer, which facilitate the strain relaxation. In addition, the behavior of the bending dislocations has been investigated in detail, and the threading dislocation bending along the growth direction is noted to relax the strain further.

Purpose IR780 iodide, a promising near-infrared dye, is widely used to prepare nanoparticles as a theranostic agent for tumor imaging and therapy. However, there are no validated (bio)analytical methods to measure IR780 in nanoparticles and tissues in literature. The aim of this study is to develop and validate a new HPLC method to measure IR780 concentration in IR780 formulations as well as a new LC–MS/MS method to measure IR780 concentration in tissue samples, particularly in liver and lung. Materials and methods IR780 granules that produced IR780 in situ self-assembled nanoparticles upon contact with water were prepared at two drug loadings (0.2 % and 0.37 %). An HPLC method was developed and validated to measure IR780 concentrations in IR780 granules and nanoparticles. Furthermore, a validated LC–MS/MS method was developed to measure IR780 in mouse liver and lung. Both HPLC method and LC–MS/MS method were validated in terms of specificity, stability, linearity, limit of detection, limit of quantification, accuracy and precision. Results Both HPLC method and LC–MS/MS method achieved the criteria for method validation. The HPLC method was accurate in the concentration range of 0.5−25 μg/mL. The measured drug loadings were 95 % of the theoretical drug loadings. The validated LC–MS/MS method can quantitatively measure the concentrations of IR780 in liver and lung. The linear range of the LC–MS/MS method was 1−1000 ng/mL for both liver and lung samples. IR780 granules showed the lung selectivity compared to IR780 solution at 2 h after oral administration. Conclusion A validated HPLC method was developed to measure IR780 concentration in pharmaceutical formulations and a validated LC–MS/MS method was developed to measure IR780 concentration in tissues. These quantitative methods provide reliable measurements of IR780 in pharmaceutic formulations and biological samples, which will significantly facilitate the research of IR780 as a theranostic agent for cancer therapy and imaging.

Ternary photocatalyst, reduced graphene oxide-ZnFe 2 O 4 -polyaniline (RZP), has been successfully developed by the in-situ polymerization of aniline on the reduced graphene oxide-ZnFe 2 O 4 (RG/ZF) surface for sewage purification. The SEM, TEM and STEM images suggest that PANI has coated the RG/ZF composite well. The XRD, TG-DTG and FT-IR analysis confirm that there are some interactions between RG/ZF composite and PANI. Importantly, the decontamination performance of RZP composites has been investigated using RhB as a model organic in view of adsorption and photocatalysis. On one hand, thermodynamic researches indicate that the adsorption behaviors of RZP composites conform to the Langmuir model, and their adsorption mechanism can be well described by the second-order kinetic model. On the other hand, RZP composites with different mass ratios of PANI to RG/ZF ( m P/RZ ) present a better photocatalytic activity than that of RG/ZF composites, and their photocatalytic behaviors under different pH could be described by the first-order kinetic model. Furthermore, it can be observed that the RZP composite with m P/RZ = 0.4 has the excellent photocatalytic activity and photocatalytic stability under pH = 1. Finally, the possible photocatalytic degradation mechanisms of the RZP composite on RhB have been discussed. These results can unveil that the prepared RZP photocatalyst is very promising for application in water purification.

Color correction algorithm based on color space conversion is an essential part in color management system. Subject to the variation in conditions such as the limitations on imaging-forming principle, device performances and machining controls, the captured images usually contain certain color distortion compared to the actual images. Therefore, the paper proposes a mind evolutionary computation (MEC)-back propagation (BP)-adaboost algorithm (Adaboost) neural network-based color correction algorithm for color image collecting equipment. MEC-BP-Adaboost is utilized in training process to establish the color mapping model, with the captured samples of the color-targets under the color image acquisition equipments as input data and the standard color data as output data. MEC-BP-Adaboost neural network-based color correction algorithm not only can further the correction accuracy, but also can solve the problem that the color correction models obtained by using the neural network methods are not unique, and the difference among that color correction models is very big. Experimental results demonstrate that the proposed method achieves much better correction performance than the polynomial regression model, the conventional BP neural network, and the genetic algorithm (GA)-BP neural network.

Magnetic reduced graphene oxide-ZnFe 2 O 4 composites (RG/ZF) were successfully prepared through a simple chemical co-precipitation method, and their composition, structure, and morphology were characterized by XRD, Raman, SEM, TEM and STEM. These results indicated that the as-prepared RGO with some defects and few reactive groups containing oxygen possessed the few-layered crystal structure, and the ZnFe 2 O 4 nanoparticles with spinel structure were homogeneously dispersed in the interlayer of graphene sheets. The interactions between two components had been investigated by TG and FT-IR. Importantly, kinetic researches indicated that the adsorption behavior of RG/ZF composite could be well described by the second-order kinetic model. Their adsorption effect on RhB conformed to the Langmuir model and belonged to the monolayer chemical adsorption, which were illustrated by thermodynamic experiment. In addition, RG/ZF composites with different mass ratio of RG to ZF ( m RG/ZF ) presented good photocatalytic activity, and their photocatalytic behavior could be described by the first-order kinetic model under different pH. Among all composites, the RG/ZF composite with m RG/ZF = 0.4 showed the best photocatalytic activity under pH = 1. However, the enhanced photocatalytic activity may arise from the effective separation of photogenerated e − -h + pairs and the positive synergetic effect between two components. Moreover, the obtained optimum RG/ZF composite had the saturation magnetization (9.8747 emu/g) enough to make it easy to be separated from solution by means of an external magnetic field. On the other hand, the antibacterial testing implied that the antibacterial properties of composite were depended on the m RG/ZF , and the RG/ZF with m RG/ZF = 0.4 likewise presented the most excellent antibacterial activity, especially to the C. albicans (its IZD and MID was respectively up to 34.5 mm and 12.5 μg/mL). Finally, the possible mechanisms of photocatalysis and antibacterial have been discussed.

Magnesium films of various thicknesses were first deposited on silicon (1 1 1) substrates by magnetron sputtering method and then annealed in annealing furnace filled with argon gas. The effects of the magnesium film thickness and the annealing temperature on the formation of Mg2Si films were investigated by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The Mg2Si thin films thus obtained were found to be polycrystalline and the Mg2Si (2 2 0) orientation is preferred regardless of the magnesium film thickness and annealing temperature. XRD results indicate that high quality magnesium silicide films are produced if the magnesium/silicon samples are annealed at 400 °C for 5 h. Otherwise, the synthesized films annealed at annealing temperatures lower than 350 °C or higher than 450 °C contain magnesium crystallites or magnesium oxide. SEM images have revealed that microstructure grains in the polycrystalline films are about 1–5 μm in dimensions, and the texture of the Mg2Si films becomes denser and more homogeneous as the thickness of the magnesium film increases.

Fe films were deposited on both heated and not-heated Si (100) substrates using direct current magnetron sputtering, and were subsequently annealed by pulsed laser with various laser energy densities. Direct formation of single-phase α-FeSi 2 was confirmed using X-ray diffraction and the surface morphology of films was characterized by scanning electron microscopy. The results show that the crystallinity of the films deposited at room temperature is improved with increasing laser energy densities, while the crystallinity of the films deposited on heated substrates is improved with increasing substrate temperatures. For the samples deposited at the room temperature, the optimal laser energy density for the formation of α-FeSi 2 is 0.95 J cm − 2 .

A CeO 2 - modified aluminide coating was obtained by composite electro-deposition Ni and CeO 2 particles on 20 steel with different holding time using pack cementation. The growth kinetics curve was given with computer fitting by measuring the thickness of the layer. Scanning electronic microscopy and X-ray energy dispersive spectrometry were used to analyze the microstructure and components of the layer. The results showed that the content of CeO 2 was up to 5.21 wt.% in the rich area of NiAl coatings, which restrain the interdiffusion between the coating and the base during the oxidation process at high temperature. Meanwhile, the growth curve obtained could offer an important basis to forecasting and controlling the depth of the coating.