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Carbon dots (CDs) are one of the carbon-based materials with remarkable optical properties, good water dispersibility and high biocompatibility. However, few studies have emphasized the intrinsic photodynamic and anticancer properties of CDs. Herein, we used CDs as photosensitizers to explore their photodynamic therapy (PDT) effect on oral squamous cell carcinoma (OSCC) cells. The obtained CDs had an effective cellular internalization capacity and possessed good biocompatibility in both CAL-27 and UM1 cells. After irradiation, the CDs showed obvious photodynamic effects on the test cells, which were confirmed by apoptosis analysis. In addition, the CDs exhibited excellent intracellular ROS generation under irradiation, and the subsequent induced cell death may be related to a lysosome-associated pathway. [ABSTRACT FROM AUTHOR]

In this work, the epoxy-based composites filled with 3-Aminopropyltriethoxysilane (KH-550) modified binary filler of hexagonal boron nitride (h-BN) flakes and h-BN whiskers were fabricated, and the thermal and dielectric properties of composites were systematically investigated. Adding h-BN whiskers to the filler could effectively form heat conduction paths and improve the phonon transmission efficiency, thereby improving the thermal conductivity of the composites. According to our results, the thermal conductivity of composite with 27 wt% h-BN flakes and 3 wt% h-BN whiskers reached up to 0.819 W·m−1·K−1, which was 3.9 times that of pure epoxy resin. At the same time, the dielectric loss value and dielectric constant of this composite at 1 MHz were 0.02678 and 4.55, respectively, while pure epoxy resin were 0.03602 and 4.33. In addition, introducing h-BN whiskers into the matrix could effectively improve the thermal stability and heat dissipation performance of composites. [ABSTRACT FROM AUTHOR]

Commercial F500 SiC powder and 6061 Al powder were chosen to fabricate the 50 vol.-% SiCp/6061Al composites via pressureless sintering. Effects of pre-treatment of the SiC powder and sintering temperature on the microstructures and properties of the composites were studied. Densification mechanism and interfacial reaction of the composites were also investigated. The results show that the composites have a high sintering ability and a low interfacial reaction activity. The density, bending strength and thermal conductivity of the composites are all sensitive to the sintering temperature. The composites sintered at 680°C are nearly fully dense and have the following optimal properties: the relative density of 98.5%, the bending strength of 495 MPa, the TC of 153 W/(m K) and the coefficient of thermal expansion of 8.1 × 10−6/°C (50–100°C), which are superior to most of the SiCp/Al composites of the similar composition reported previously. [ABSTRACT FROM PUBLISHER]

Component recognition is a very important issue in the analysis of mixed three-dimensional fluorescence spectra and it can be realized by calculating the similarity index between the reference spectra and the computed spectra from the trilinear decomposition of the three-dimensional data arrays. However, the most popular similarity index available in the literature for processing three-dimensional fluorescence spectra takes advantage of only part of the information from the trilinear decomposition. It works well when there are clear differences between the component spectra, but it may fail when the spectra are severely overlapped. In order to overcome the shortcomings and to adapt to the rapid development of online monitoring, we propose a type of integrated similarity index (ISI) that is particularly superior for component recognition in mixtures with severely overlapped spectra. The ISI makes full use of as much information of the three-dimensional fluorescence spectra as possible, namely, of both the waveform and the characteristic peak wavelength, as well as both the emission spectra and the excitation spectra. With the ISI, the recognition process can be accomplished automatically and more accurately in extreme cases than the traditionally defined similarity indices that are based on only one specific feature. The feasibility of the ISI is demonstrated by experiments with mixtures of phenol, cresol, and thymol. [ABSTRACT FROM AUTHOR]