Attempts to reflect the physiology of organs is quite an intricacy during the tissue engineering process. An ideal scaffold and its surface topography can address and manipulate the cell behavior during the regeneration of targeted tissue, affecting the cell growth and differentiation significantly. Herein, silk fibroin (SF) nanoparticles were incorporated into poly( l -lactic acid) (PLLA) to prepare composite scaffolds via phase-inversion technique using supercritical carbon dioxide (SC-CO 2 ). The SF nanoparticle core increased the surface roughness and hydrophilicity of the PLLA scaffolds, leading to a high affinity for albumin attachment. The in vitro cytotoxicity test of SF/PLLA scaffolds in L929 mouse fibroblast cells indicated good biocompatibility. Then, the in vitro interplay between mouse preosteoblast cell (MC3T3-E1) and various topological structures and biochemical cues were evaluated. The cell adhesion, proliferation, osteogenic differentiation and their relationship with the structures as well as SF content were explored. The SF/PLLA weight ratio (2:8) significantly affected the MC3T3-E1 cells by improving the expression of key players in the regulation of bone formation, ie, alkaline phosphatase (ALP), osteocalcin (OC) and collagen 1 (COL-1). These results suggest not only the importance of surface topography and biochemical cues but also the potential of applying SF/PLLA composite scaffolds as biomaterials in bone tissue engineering.

low temperature growth, single crystal compound semiconductor, back-end-of-line device, heterogeneous integration, 3D integration In this work, a low temperature templated liquid phase (LT-TLP) growth process is presented, that enables one to directly grow high optoelectronic quality single crystalline compound semiconductors (InP and InAs) on amorphous dielectrics at temperatures below 400 o C. Uniquely, the material quality is optimal when InP is grown at 300 o C, a temperature which is low enough to enable back-end-of-line growth on fully fabricated Si CMOS circuits. Using this low-temperature grown InP, a transistor fabrication process is then entirely carried out at 300 o C or below, and an indium phosphide nanoribbon field effect transistor with excellent on/off ratios is demonstrated, indicating low defect density in the material. Overall, this approach enables growth of large area (tens of micron) single crystal compound semiconductor at low temperatures, establishing a back-end-of-line (BEOL) compatible process for monolithic 3D device integration.

Phase inversion using supercritical carbon dioxide (SC-CO2) has been widely used in the development of tissue engineering scaffolds, and particular attention has been given to obtaining desired morphology without additional post-treatments. However, the main challenge of this technique is the difficulty in generating a three-dimensional (3D) nanofiber structure with a rough surface in one step. Here, a poly(L-lactic acid) (PLLA) 3D nanofiber scaffold with a rough surface is obtained via phase inversion using SC-CO2 by carefully choosing fabrication conditions and porogens. It is found that this method can effectively modulate the structure morphology, promote the crystallization process of semicrystalline polymer, and induce the formation of rough structures on the surface of nanofibers. Meanwhile, the porogen of ammonium bicarbonate (AB) can produce a 3D structure with large pores, and porogen of menthol can improve the interconnectivity between the micropores of nanofibers. A significant increase in the fiber diameter is observed as the menthol content increases. Furthermore, the menthol may affect the mutual transition between the α' and α crystals of PLLA during the phase separation process. In addition, the results of protein adsorption, cell adhesion, and proliferation assays indicate that cells tend to have higher viability on the nanofiber scaffold. This process combines the characteristic properties of SC-CO2 and the solubility of menthol to tailor the morphology of polymeric scaffolds, which may have potential applications in tissue engineering.

We demonstrate high electron mobility single-crystal InAs mesas monolithically integrated on amorphous dielectric substrates at a growth temperature of 300 °C. Critically, a room temperature mobility of ∼5800 cm 2 /(V s) was measured, the highest mobility reported for any thin-film semiconductor material system directly grown on a nonepitaxial substrate. Detailed modeling of the scattering mechanisms in the grown material indicates that the mobility is limited by surface roughness scattering, not the intrinsic material quality. We project that reducing the RMS surface roughness of the InAs from 1.8 to 1 nm would produce materials with room temperature mobilities of >10000 cm 2 /(V s), and RMS roughness of 0.5 nm would result in mobility of ∼20000 cm 2 /(V s), essentially identical with epitaxially grown materials. These results pave the way for growth of high-mobility materials directly onto the back end of silicon CMOS wafers and other nonepitaxial substrates such as glass, as well as polymers for flexible electronics.

Abstract. Nanotechnology is the rapid developing. The nanotechnology in battery materials can enhance the storage capacity of a battery, reduce swelling and loss of the battery and improve use efficiency, which is of positive significance for the electrical equipment. Based on the analysis of current development of nano battery, the preparations of several nano materials for battery are discussed, which can be better applied in the production of life and point out the direction for the development of modern nano battery technology. Current Development Situation of Nano-materials for BatteriesIntroduction to Nano-battery. The nano battery is a battery made of nanometer technology, and the size of the material is less than 100 nm. These cells are of nanometer size or can be combined together as a large cell such as a nano pore cell. Lithium ion battery technology using traditional active materials. The size of cobalt oxide or manganese oxide ranges from 5 to 20 microns. Many disadvantages of Nano Engineering can improve the existing battery technology, such as low power density and volume expansion. The chemical energy can be converted into electrical energy, which is composed of three parts: anode (positive electrode), cathode (negative electrode) and electrolyte. The anode and cathode have two different chemical potentials, depending on the reaction at the two end. The electrolyte can be either a solid or a liquid, a dry material or a wet material, respectively. The boundary between the electrode and the electrolyte is called the electrolyte phase, and the chemical energy stored in the cell is converted to electrical energy by the voltage applied to the electrode.Shortages of Traditional Battery. The ability of the battery to store electricity depends on its energy density and power density, and the cycle and volume expansion are also important considerations. In order to improve the battery technology, it is necessary to maximize the cycle capacity and energy and power density, and the volume expansion must be minimized. During lithium insertion, the volume of the electrode expands, causing mechanical strain. Mechanical strain damages the structural integrity of the electrode, leading to fracture. In the current lithium ion battery technology, lithium diffusion rate is slower. When the volume expansion of the nanoparticles is smaller than that of the total volume of the cell, the nano particles can reduce the mechanical strain on the material when the battery goes through the cycle. The small volume expansion associated with the nanoparticles also improves the reversibility of the battery, and the battery undergoes many cycles without loss of charge.