the kinetics of catalyst deactivation and coke formation during dehydrogenation of propane over supported pt–based catalysts and, in particular, the effect of alkali metal promoters on catalyst activity and stability were studied. the analysis of propane conversion data showed that there is an optimum level of alkali metal promoter loading for both catalyst activity and stability.a model based ...

In this paper, we introduce variable coding rate (VCR) control to OFDM adaptive modulation scheme (OFDM AMS) in order to realize high throughput with relatively simple transceiver configurations in a dynamic parameter controlled-orthogonal frequency and time division multiple access (DPC-OF/TDMA). In the proposed system, multilevel transmit power control (MTPC) is not employed to simplify hardw...

Discrete-rate spectrum balancing in interference-limited multi-user and multi-carrier digital subscriber lines (DSL) is a large-scale, non-convex and combinatorial problem. Previously proposed algorithms for its (dual) optimal solution are only applicable for networks with few users, while the suboptimality of less complex bit-loading algorithms has not been adequately studied so far. We deploy...

We consider two non-iterative algorithms of adaptive power loading for multicarrier modulation (MCM) system, The first one minimizes the average power of the system transmitter and ensures the preset average bit-error rate, while the second reduces the average transmitting power subject to the given values of demanded bit-error rate and of the outage probability. The algorithms may be used for ...

UNLABELLED BACKGROUND A modified laboratory-scale upflow anaerobic sludge blanket (UASB) reactor was used to obtain methane by treating hydrous ethanol vinasse. Vinasses or stillage are waste materials with high organic loads, and a complex composition resulting from the process of alcohol distillation. They must initially be treated with anaerobic processes due to their high organic loads. ...

Multicarrier modulation is a powerful transmission technique that provides improved performance in various communication fields. A fundamental topic of multicarrier communication systems is the bit and power loading, which is addressed in this article as a constrained multivariable nonlinear optimization problem. In particular, we present the main classes of loading problems, namely, rate maxim...

The chitosan nanoparticles used widely as a drug delivery systems recently. In the present study the Echis carinataus snake venom loaded chitosan nanoparticles were prepared based on ionic gelation of tripolyphosphate and chitosan. The nanoparticles physicochemical characteristics, stability and biological activity of encapsulated venom were studied. The particles were spherical in shape and th...

a study was performed in hybrid up flow anaerobic sludge blanket (huasb) and anaerobic filter (af) reactors to compare the start-up time and optimum hrt required for the treatment of poultry slaughterhouse wastewater under similar loading conditions. initially, the reactors were started at an olr of 0.77 kg cod/m3.d and hrt of 36 h. loading rates were increased by reducing hrt 24, 16, 12, 10 an...

The paper considers the maximum facilitation of rock breaking at a predetermined optimum pattern placement weapons and completeness saturation by cutter teeth. conditions for increasing productivity newly established drill bit obtaining desired effect in kinetic interpretation are given.