hydrogen can be produced for fuel cell applications by using methanol steam reforming reaction. in this article, a method was developed for regeneration of accelerated deactivated methanol-steam-reforming catalyst. successive deactivation–regeneration cycles were studied in a 250 hours test for the first time including 6 regeneration cycles. it is shown that regeneration of the catalyst in dilu...

fischer-tropsch synthesis is a promising route for production of light olefins via co hydrogenation over transition metals. co is one of the most active metals for fischer-tropsch synthesis. some different variables such as preparation parameters and operational factors can strongly affect the selectivity of fischer-tropsch synthesis toward the special products. in the case of preparation varia...

nowadays, due to increasing the complexity of ic engines, calibration task becomes more severe and the need to use surrogate models for investigating of the engine behavior arises. accordingly, many black box modeling approaches have been used in this context among which network based models are of the most powerful approaches thanks to their flexible structures. in this paper four network base...

Activation and deactivation of media items plays a fundamental role in the playing of multimedia and time-based hypermedia presentations. Activation and deactivation information thus has to be captured in an underlying document format. In this paper we show that a number of aspects of activation and deactivation information can be captured using both link structures and events in time-based hyp...

introduction: rheumatic heart disease still remains one of the leading causes of congestive heart failure and death owing to valvular pathologies, in developing countries. valve replacement still remains the treatment of choice in such patients.the aim of this study wasto analyze the postoperative outcome of  double valve replacement (mitral and aortic ) in patients of rheumatic heart disease. ...

A three-dimensional CFD modeling was carried out to investigate effects of VVT/VVA on gas exchange and fuel-air mixing processes in a diesel HCCI engine with early fuel injection. Four VVT/VVA strategies were conducted for this study: i) NVO strategy with fixed EVO and IVC timings but variable valve lifts – referred as NVO Strategy; ii) NVO strategy with fixed valve profiles but variable EVO an...

Polyethylene glycol (PEG 4000), Browse Plus (BP), wood ash (WA) and boiling water were evaluated as tannin deactivation methods on tannins in Acacia nilotica fruits. Twenty four Matebele goats of mean body mass, 38.7 ± 3.12 kg, were used in a digestibility and nitrogen balance trial. A completely randomized design was used, and the initial weight was used as a covariate in data analysis. The go...

In states of sodium deficiency many animals seek and consume salty solutions to restore body fluid homeostasis. These behaviors reflect the presence of sodium appetite that is a manifestation of a pattern of central nervous system (CNS) activity with facilitatory and inhibitory components that are affected by several neurohumoral factors. The primary focus of this review is on one structure in ...