this paper reports the synthesis of polypyrrole coated sno2/znoelectrospunnanofibers via vapor phase polymerization method. in order to prepare one dimensional (sno2-zno)/polypyrrole with the core sheath structure, first sno2-zno composite nanofibers were synthesized via electrospinning method followed by adsorption of fe3+ on the surface of the sno2-zno nanofibers and finally pyrrole was polym...

Introduction: Nearly four decades of experimental studies have failed to agree on an isotopic composition for solar wind (SW) nitrogen implanted in lunar regolith grains. Estimates of ! 15 N range from > +200 ‰ [1] to < -250 ‰ [2]. Its actual value is crucial, not only for untangling component mixtures in the lunar system but also in elucidating the sources and isotopic evolution of N in other ...

The large-scale simultaneous extraction and concentration of aqueous solutions of triazine analogs, and aflatoxins, through a hydrocarbon-based membrane (e.g., polyethylene, polyethylene/polypropylene copolymer) under ambient temperature and atmospheric pressure is reported. The subsequent adsorption of analyte in the extraction chamber over the lignin-modified silica gel facilitates the proces...

the examination of available vapor pressure data in the case of the methane, ethane, propane and butane halogenated refrigerants, allowed recommendations of standard equations for this property. in this study, three new models include a general correlation; a substance-dependent correlation and an artificial neural network (ann) approach have been developed to estimate the saturated vapor press...

nanoporous graphene which is used as nanosorbent was synthesized by chemical vapor deposition method via porous zinc oxide nanocatalyst. the reaction was carried out using methane as the carbon source and hydrogen as the carrier gas in a ratio of 4:1 at the temperature ranging 900-1050°c for 2-50 min. the product was characterized by scanning electron microscopy, transmission electron microscop...

Estimates are made of the effect of changes in tropospheric water vapor on the climate sensitivity to doubled carbon dioxide (CO2), using a coarse resolution atmospheric general circulation model coupled to a slab mixed layer ocean. The sensitivity of the model to doubled CO2 is found as the difference between the equilibrium responses for control and doubled CO2 cases. Clouds are specified to ...

Setting up accurate and user-friendly models of physical, chemical and biological processes is particularly useful for design and optimization of vapor extraction/bioventing (SVE/SBV) systems, and prediction of residual concentrations and remediation time. Despite improvment of model structures, the optimum experiments should be designed for model calibration. The feasibility of parameter estim...

This paper presents results of a numerical investigation of soil vapor extraction (SVE) systems at the laboratory scale. The SVE technique is used to remove volatile chlorinated hydrocarbons (VCHC) from the water-unsaturated soil zone. The developed numerical model solves equations of flow, transport and interfacial mass transfer regarding an isothermal n-component and three-phase system. The m...

Smokeless powder additives are usually detected from an extraction of post-blast residues or unburned powder particles followed by chromatographic analyses. This work presents the first comprehensive study of the detection of volatile and semi-volatile additives of smokeless powders using solid phase microextraction (SPME) as a sampling and pre-concentration technique. The goal of this study is...

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...