We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry-climate model to be +0.3 W/(m(2)⋅K), which w...

Humidification process is one of the applications of membrane contactor in which partial pressure of a vapor in the gas stream increases. In this study, two different polyethersulfone and polyetherimide hollow fiber membranes were fabricated and characterized by various test methods and their performance in humidification process under different operating conditions was investigated. The PES me...

Vapor-phase synthesis techniques of polymeric nanostructures offer unique advantages over conventional, solution-based techniques because of their solventless nature. In this work, we report the fabrication of coaxial polymer nanotubes using two different chemical vapor deposition methods. The fabrication process involves the deposition of an outer layer of the conductive polyaniline (PANI) by ...

Anthropogenic modification of the water cycle involves a diversity of processes, many of which have been studied intensively using models and observations. Effective tools for measuring the contribution and fate of combustion-derived water vapor in the atmosphere are lacking, however, and this flux has received relatively little attention. We provide theoretical estimates and a first set of mea...

In this investigation, Ti/TiN nanolayer and TiN single layer coatings were coated on substrate of AISI 316L stainless steel by applying physical vapor deposition (PVD) using the type of cathodic arc evaporation (CAE). The evaluation of microstructure were carried out using x-ray diffraction (XRD), nanoindentation, atomic force microscopy (AFM) as well as scanning electron microscopy (SEM). Pola...

We numerically investigate the nonlinear evolution of the interface of a thin liquid-vapor bilayer system confined by rigid horizontal walls from both below and above. The lateral variation of the vapor pressure arising from phase change is taken into account in the present analysis. When the liquid vapor is heated cooled and gravity acts toward the liquid, the deflection of the interface monot...

It’s considered that pool boiling heat transfer is closely related to the intermittent behavior of vapor mass and the consumption of macro-layer on the heated surface. Many experiments have been carried out to support the macrolayer evaporation model, however, little has been done in the numerical simulation of boiling heat transfer. This paper reports a method to simulate heat transfer near th...

The heat transfer performance of vapor-condenser has been studied under different temperature of cold trap and different thickness of the frost layer in this paper. The relationship between dimensionless number and is obtained. The results show that the capturing efficiency of cold trap increases with the decrease of the surface temperature of vapor-condenser. The frost accumulated on the surfa...

A novel scheme is presented for production of a thin (< 1 mm) uniform vapor layer over a large surface area (> 100 cm 2) by pulsed laser ablation of a solid surface. Instead of dispersing the laser energy uniformly over the surface, a modified Fabry-Perot interferometer is employed to concentrate the laser energy in very narrow closely-spaced concentric rings. This approach may be optimized to ...