Abstract: Solution for the complete removal of carbon
monoxide from the exhaust gases still poses a challenge to the
researchers and this problem is still under development. Modeling for
reduction of carbon monoxide is carried out using heterogeneous
reaction using low cost non-noble metal based catalysts for the
purpose of controlling emissions released to the atmosphere. A
simple one-dimensional model was developed for the monolith using
hopcalite catalyst. The converter is assumed to be an adiabatic
monolith operating under warm-up conditions. The effect of inlet gas
temperatures and catalyst loading on carbon monoxide reduction
during cold start period in the converter is analysed.
Abstract: In this paper is investigated a possible
optimization of some linear algebra problems which can be
solved by parallel processing using the special arrays called
systolic arrays. In this paper are used some special types of
transformations for the designing of these arrays. We show
the characteristics of these arrays. The main focus is on
discussing the advantages of these arrays in parallel
computation of matrix product, with special approach to the
designing of systolic array for matrix multiplication.
Multiplication of large matrices requires a lot of
computational time and its complexity is O(n3 ). There are
developed many algorithms (both sequential and parallel) with
the purpose of minimizing the time of calculations. Systolic
arrays are good suited for this purpose. In this paper we show
that using an appropriate transformation implicates in finding
more optimal arrays for doing the calculations of this type.
Abstract: The performance of mortar subjected to high
temperature and cooled in normal ambient temperature was examined
in the laboratory to comply with the situation of burning & cooling of
a structure. Four series of cubical (5 X 5 X 5 cm) mortar specimens
were made from OPC, and partial replacement (10, 15, 20, 25 &
30%) of OPC by Rice Husk Ash (RHA) produced in the uncontrolled
environment. These specimens were heated in electric furnace to 200,
300, 400, 500 and 7000C. The specimens were kept in normal room
temperature for cooling. They were then tested for mechanical
properties and the results shows that particular 20% RHA mixed
mortar shows better fire performance.
Abstract: This paper presents a comparative study on
Vanadyl Phthalocyanine (VOPc) thin films deposited by thermal
evaporation and spin coating techniques. The samples
were prepared on cleaned glass substrates and annealed at
various temperatures ranging form 95oC to 155oC. To obtain
the morphological and structural properties of VOPc thin
films, X-ray diffraction (XRD) technique and atomic force
microscopy (AFM) have been implied. The AFM topographic
images show a very slight difference in the thermally grown
films, before and after annealing, however best results are
achieved for the spin-cast film annealed at 125oC. The XRD
spectra show no existence of the sharp peaks, suggesting the
material to be amorphous. The humps in the XRD patterns
indicate the presence of some crystallites.
Abstract: The temperature distribution and the heat transfer
rates through a multi-layer door of a furnace were investigated. The
inside of the door was in contact with hot air and the other side of the
door was in contact with room air. Radiation heat transfer from the
walls of the furnace to the door and the door to the surrounding area
was included in the problem. This work is a two dimensional steady
state problem. The Churchill and Chu correlation was used to find
local convection heat transfer coefficients at the surfaces of the
furnace door. The thermophysical properties of air were the functions
of the temperatures. Polynomial curve fitting for the fluid properties
were carried out. Finite difference method was used to discretize for
conduction heat transfer within the furnace door. The Gauss-Seidel
Iteration was employed to compute the temperature distribution in
the door.
The temperature distribution in the horizontal mid plane of the
furnace door in a two dimensional problem agrees with the one
dimensional problem. The local convection heat transfer coefficients
at the inside and outside surfaces of the furnace door are exhibited.