Background and aim: Eczema is a common inflammatory skin disease. Although history and physical examination are important in diagnosis of allergen, because of extent of environmental allergens, those are not simply recognized. The objective of this study was to determine allergens in patients with contact or atopic dermatitis referred to Razi hospital.Materials and Meth...

In response to increasing environmental concern over the use of chlorofluorocarbons (CFC's) to clean printed circuit assemblies, many surface mount operations are converting to water soluble or no-clean type solder pastes. Current trends indicate that this conversion will progress rapidly until water soluble and no-clean pastes constitute the majority of the product mix. With the introduction o...

Controlling surface wettability, expressed in terms of contact angle, is a significant issue in nanotechnology. In this paper, through extensive molecular dynamics simulations, we show that the contact angle of water droplet on a TiO2 surface is considerably influenced by the temperature variations, i.e. as the temperature increases, the contact angle decreases and the surface becomes more hydr...

tissue engineering is defined as the designing and engineering of structures to rebuild and repair a body damaged tissue. scaffolding poly hydroxy butyrate valraty (phbv) has shown good biocompatibility and biodegradable properties. nanofibers have improved the performance of biomaterials, and could be considered effective. one of the important methods for designing nanofiber scaffold is the el...

In this paper, we present superhydrophobic micro/nano dual structures (MNDS). By KOH-etching of silicon, well-designed microstructures, including inverted pyramids and V-shape grooves, are first fabricated with certain geometry sizes. Nanostructures made of high-compact high-aspect-ratio nanopillars are then formed atop microstructures by an improved controllable deep reactive ion etching (DRIE...

Basic electrowetting theory predicts that a continued increase in applied voltage will allow contact angle modulation to zero degrees. In practice, the effect of contact angle saturation has always been observed to limit the contact angle modulation, often only down to a contact angle of 60 to 70. The physical origins of contact angle saturation have not yet been explained successfully and uneq...

We present the first quantitative measurement of the receding contact angle between a soft viscoelastic material and a solid surface during the debonding of the material. We developed a new method of observation, based on the technique pioneered by Yamaguchi et al. (T. Yamaguchi, K. Koike, and M. Doi, Euro. Phys. Lett., 2007, 77, 64002). In a probe-tack geometry, we obtained a 3D-like view of t...

The contact angle of a liquid droplet on a solid surface is a direct measure of fundamental atomic-scale forces acting between liquid molecules and the solid surface. In this work, the validity is assessed of a simple equation, which approximately relates the contact angle of a liquid on a surface to its density, its surface tension, and the effective molecule-surface potential. This equation i...

Computational fluid dynamics is implemented to investigate the influence of the wheel contact patch on the global car aerodynamics. Two main aspects of the problem are the contact step and patch shape. Three important parameters: step height, cut angle, and tire tread shape are taken into consideration. For validations of the numerical results, the experimental data are also considered. The obt...