An increasing number of studies have investigated the effects of nanoparticles (NPs) on microbial systems; however, few existing reports have focused on the defense mechanisms of bacteria against NPs. Whether secondary metabolism biosynthesis is a response to NP stress and contributes to the adaption of bacteria to NPs is unclear. Here, a significant induction in the surfactin production and bi...

We report our recent results on an optimization study of focused ion beam (FIB) nano-structuring of Bragg gratings in Al2O3 channel waveguides. By optimizing FIB milling parameters such as ion current, dwell time, loop repetitions, scanning strategy, and applying a top metal layer for reducing charging effects and improving sidewall definition, reflection gratings with smooth and uniform sidewa...

The Minnesota Nano Center’s Keller Hall facility includes an atomic layer deposition (ALD) machine that is capable of depositing uniform alumina (Al2O3), hafnium oxide (HfO2), silicon dioxide (SiO2), zinc oxide (ZnO), and titanium dioxide (TiO2). ALD works by building alternate layers on a film using two different precursor gases – one usually supplying the metallic atoms and water vapor (H2O) ...

A feasible "NOSE" (nanoparticles-catalyzed organic synthesis enhancement) protocol has been developed for N,N-diformylation of bisuracil derivatives using nano-Al2O3 rods as an efficient, inexpensive, and recyclable catalyst under solvent-free reaction condition at 40°C. The catalyst was reused up to the 4th cycle without affecting the rate and yield of the N,N-diformylation products appreciably.

PURPOSE The purpose of this in vitro study is to examine the effects of a nano-structured alumina coating on the adhesion between resin cements and zirconia ceramics using a four-point bending test. MATERIALS AND METHODS 100 pairs of zirconium bar specimens were prepared with dimensions of 25 mm × 2 mm × 5 mm and cementation surfaces of 5 mm × 2 mm. The samples were divided into 5 groups of 2...

Selective laser melting (SLM) offers significant potential for the manufacture of the advanced complex-shaped aluminium matrix composites (AMCs) used in the aerospace and automotive domains. Previous studies have indicated that advanced composite powders suitable for SLM include spherical powders with homogeneous reinforcement distribution, a particle size of less than 100 μm and good flowabili...

In this study, UV-curable urethane acrylate UA synthesized and then characterized by FTIR and HNMR. For better dispersion of nanoparticles in polymeric matrix, nano Al2O3 was modified by silane coupling agent and then its nanocomposites were prepared. The characteristics of synthesized nanocomposites were analyzed by TGA, DMA and infrared thermography. The results signify that adding nano Al2O3...

This paper describes thermal modeling of Vapor Compression Refrigeration System using R134a in primary circuit and AL2O3-Water based nanofluids in secondary circuit. The model uses information of the secondary fluids input conditions geometric characteristics of the system, size of nanoparticles and the compressor speed to predict the secondary fluids output temperatures, the operating pressure...

Connecting prostheses to the implant abutments has become a concern and achieving a satisfactory retention has been focused in cement-retention prostheses recently. Sandblasting is a method to make a roughened surface for providing more retention. The aim of this study was to compare effects of nano and micro airborne abrasive particles (ABAP) in roughening surface of implant abutments and furt...

Localized surface plasmon resonance (LSPR) biosensors are employed to detect target biomolecules which have particular resonance wavelengths. Accordingly, tunability of the LSPR wavelength is essential in designing LSPR devices. LSPR devices employing silver nano-particles present better efficiencies than those using other noble metals such as gold; however, silver nano-particles are easily oxi...