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This study presents a combined strategy of bidisperse boron nitride (BN) and surface modification to improve the thermal conductivity (κ) of the BN-epoxy composite. Surface modification of hexagonal BN was carried out with benzoic acid (BA). The optimal weight ratio of large and small BN (BNl and BNs) was 8:2 for their connectivity in the epoxy matrix. For 50 wt% filler content, the BNl8s2-BA composite has a much higher κ of 2.71 W/m K (out-plane direction), which is 12.3, 1.32, and 1.50 times higher than that of the pure epoxy, and its composite with BNl10s0-BA and BNl8s2, respectively. The chemical-sensitive analyses indicate that carboxyl-carboxylate interaction occurred in partially deprotonated benzoic acid on BN during the epoxy curing process, resulting in in-situ formation of a continuously thermal conductive pathway, which is responsible for the improved κ.

Recently, the appeal of 2D black phosphorus (BP) has been rising due to its unique optical and electronic properties with a tunable band gap (≈0.3-1.5 eV). While numerous research efforts have recently been devoted to nano- and optoelectronic applications of BP, no attention has been paid to promising medical applications. In this article, the preparation of BP-nanodots of a few nm to

This study investigates the feasibility of using an adipose-derived mesenchymal stem cell (ASC)-seeded acellular dermal matrix (ADM) along with low-level laser therapy (LLLT) to repair bone defect in athymic nude mice. Critical-sized calvarial defects were treated either with ADM, ADM/LLLT, ADM/ASCs, or ADM/ASCs/LLLT. In micro-computed tomography scans, the ADM/ASCs and the ADM/ASCs/LLLT groups showed remarkable bone formation after 14 days. Additionally, bone regeneration in the ADM/ASCs/LLLT group was obvious at 28 days, but in the ADM/ASCs group at 56 days. Bone mineral density and bone tissue volume in the ADM/ASCs/LLLT group significantly increased after 7 days, but in the ADM/ASCs group after 14 days. Histological analysis revealed that the defects were repaired in the ADM/ASCs and the ADM/ASCs/LLLT group, while the defects in the ADM and the ADM/LLLT groups exhibited few bone islands at 28 and 56 days. The successful seeding of ASCs onto ADM was confirmed, and LLLT enhanced the proliferation and the survival of ASCs at 14 days. Our results indicate that ASC-seeded grafts promote bone regeneration, and the application of LLLT on ASC-seeded ADM results in rapid bone formation. The implantation of an ASC-seeded ADM combined with LLLT may be used effectively for bone regeneration.

A quantitative analysis of the decreasing rate of the monomer and increasing rate of the polymerization was made by monitoring radiation level increments using Raman spectroscopy within the therapeutic radiation range for a normoxic polymethacrylic acid gel dosimeter. The gel dosimeter was synthesized by stirring materials such as gelatin, distilled water, methacrylic acid, hydroquinone and tetrakis phosphonium chloride at , and the synthesized gel was contained in a 10- mm diameter and 32-mm high vial to conduct measurement. 24 hours after gel synthesis, it was irradiated from 0 Gy to 20 Gy by 2 Gy using a Co-60 radiotherapy unit. With use of the Cryo FE-SEM, structural changes in the 0 Gy and 10 Gy gel dosimeters were investigated. The Raman spectra were acquired using 532-nm laser as the excitation source. In accordance with fitting the changes in C-COOH stretching (801 ), C=C stretching (1639 ) and vinyl stretching (3114 ) vibrational modes for monomer and bending vibrational mode (1451 ) for polymer, sensitive parameter S for each mode was calculated. The values of S for monomer bands and polymer band were ranged in Gy and Gy, respectively, which shows a relatively good conformity of the decreasing rate of monomer and the increasing rate of polymerization within the range of error.

Multilayer transparent electrodes, having a much lower electrical resistance than the widely used transparent conducting oxide electrodes, were prepared by using magnetron sputtering. The multilayer structure consisted of three layers, tin-doped indium oxide (ITO)/Ag/ITO. Because only Ag deposits with a thickness larger than 14 nm form a continuous film, the optimum thickness of Ag thin films was determined to be 14 nm for high optical transmittance and good electrical conductivity. With about 55–60 nm thick ITO films, the multilayer showed a high optical transmittance in the visible range of the spectrum and had color neutrality. The electrical and optical properties of the ITO/Ag/ITO multilayer were changed mainly by Ag film properties, which were affected by the deposition process of the upper layer. A high quality transparent electrode, having a resistance as low as 4 Ω/□ and a high optical transmittance of 90% at 550 nm, was obtained and could be reproduced by controlling the preparation process parameters properly. It could satisfy the requirement for the SVGA mode STN-LCD.

We observed that single-walled carbon nanotube (SWNT) was aligned in the presence of TTF. This alignment was induced by a specific interaction between SWNT and tetrathiafulvalene (TTF), a well-known organic donor. The interaction between the two molecules can be explained by a charge-transfer, which was confirmed by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The binding energies of S (2P1/2) and S (2P3/2) were shifted from 163.0 eV and 164.1 eV to 163.9 eV and 165.1 eV, respectively. In Raman spectra of the SWNT-TTF, three peaks of SWNT in radial breathing mode were also upshifted by 4–5 cm−1. The charge-transfer interaction also contributed in modifying the electronic structure of SWNT and furthermore enhanced the electrical conductivity of SWNT. A more conductive thin film was fabricated using the SWNT-TTF. Four-probe measurement revealed that the surface resistance of the SWNT-TTF film was reduced to 4.359 Ω at room temperature while that of SWNT film was 6.894 Ω. These results enable carbon nanotubes to be utilized more for practically for industrial applications in fabricating peculiar nano-sized building blocks.