Al-Bahir Journal for Engineering and Pure Sciences

Let D be a one disconnecting arc space, f:D→D be a continuous map, in this work
we get:
1- If f is transitive map. Then the set of all periodic points is dense in D.
2- If f is transitive and has a point of odd period greater than one if and only if f2
is transitive and f has dense periodic points.
3- f2 is transitive and f has dense periodic points if and only if f is totally transitive
4- f is totally transitive if and only if f is topologically mixing.
5- If f is piecewise monotone Then f is topologically mixing if and only if for
every arc K⊆D, there is an n such that f^n (K)=D

Modified Williamson-Hall (W-H) models were employed to estimate the
changing of the microstructural parameters of Fe2O3 thin films with increasing
annealing temperature (Ta). These models areW-H-anisotropic strain model (W-HASM),
W-H-isotropic strain model (W-H-ISM) and W-H-energy density model
(W-H-EDM). To calculate crystallite size, Scherrer equation and its modified
equation were used. Also crystallite size, lattice stress, strain, dislocation density and
deformation energy density have been determined by these models. By increasing
Ta, crystallite sizes were increased according to all models. Three modified (W-H)
models were used to calculate strain, it was negative and its values increase with
Ta. According to W-H-ASM and W-H-EDM stress, dislocation density and lattice
strain energy density reach minimum values when the temperature reaches (500)
oC.

The resistance of concrete to damage due to freezing-thawing and acid attack
has become an increasingly important factor to be considered in both mix concrete
design and its placing and curing techniques. In this study, the primary goal was
to investigate whether a gasification ash GA from Al-Mussaib electrical power
station can be used as a supplementary cementitious material in reactive powder
concrete RPC. Strength and durability tests were conducted in order to get a good
understanding of the mechanical features of concrete exposed to severe conditions
at (28) and (56) days respectively.
The results of the experiments show that the use of gasification ash as a
supplementary cementitious material has a positive effect on both compressive
and splitting strength development of reactive powder concrete up to (10%) of
replacement. Above (10%) gasification ash has no further increase in the strength
of concrete. The exposure to higher cycles of freezing-thawing and larger
concentrations of acid attack have higher detrimental effect than those of lower
concentrations.

Electronic structures of three suggested aluminum metal complexes are relax
using SDD-B3LYP/DFT method. The structural parameters and energies were
calculated for each complex. The excitation energy of the complex was obtained
by using the TD-DFT/B3LYP method with SDD basis sets. EHOMO, ELUMO
and LUMO-HOMO energy gap, global hardness and softness were calculated to
predict the chemical activity of the complexes. That results showed the aluminum
metal complexes play a significant rule such as catalysts in many chemical reactions
as in polymerization processes

This study includes the use of economic raw material available in Iraq, which
is available in the Western Desert of Iraq, where the knowledge of the effect
of some additives on the properties of the Iraqi kaolin allows for use in the
future industrial applications for the country. The samples were prepared from
(90%,70%Kaolin+30% meta kaolin) with two types of additives, the first type
is the powder of silicon carbide(SiC) and the second type of additives is the fire
brick powder(FBP) which was prepared from the wastes of the furnace linings.
The samples were fired at the temperature of (1100), (1200), (1300), (1400) and
(1500) Co and several properties were studied such as bulk density, open porosity
and coefficient of thermal conductivity. The addition of (10%) silicon increases the
thermal conductivity and open porosity coefficient and reduces the bulk density,
while the addition of (5%SiC + 5%FBP) have an intermediate property between
(10%) Silicon powder and (10%) FBP. While samples contain (10%) FBP have
lower open porosity and coefficient of thermal conductivity with larger bulk
density.

The wireless communication has developed very fast since its creation. So for
efficient communication we require miniature sized antennas such as microstrip
antenna. In this paper, it proposes an efficient wide band rectangular microstrip
antenna. In Equally important this design of future antenna for 5G mobile
communication, a rectangular patch is mounted on FR-4 substrate material with
dielectric constant (εr =4.4). A slot shape (] [) is etched on the rectangular patch
to provide wideband operation, which provide a wider bandwidth of (20%) and
high gain of (7.41) db. Antenna design and simulation were carried out in Finite
Element Method (FEM) based High Frequency Structural Simulation (HFSS) tool.
This antenna has good performance in terms of antenna Band width, return losses,
VSWR, Characteristics impedance, and gain at the frequency (5.1) GHz

Iraq is characterized by high abundance of solar energy, which can run many
solar energy systems, including adsorption refrigeration systems. A solar-powered
adsorption ice maker was built in Baghdad- Iraq. The ice maker works on two
adsorption pairs, namely activated carbon and methanol. The unit generator is a
flat plate solar collector of (0.211) m2 filled with a grain activated carbon. The
flat plate collector was covered using a glass sheet of 6 mm thickness. A (3) kg of
granular activated carbon type (NORIT PK 1-3) of particle size is of (3.15) mm is
used as an adsorbent. Methanol is used as a desorbent medium. Different mass of
methanol is used to achieve different mass ratios of activated carbon and methanol.
A natural air-cooled condenser was used to condense the methanol vapour, while,
the evaporator was immersed in a water bath of 1-litre volume, intended to be
frozen. The maximum solar coefficient of performance is about 0.36, while the
minimum is approximately (0.1). The daily production of ice was (1) litre when
the top collector area of (0.211) m2, which is equivalent to (4.8) kg ice/m2.day

The purpose of this article is evaluation of the possibilities of using denitrifying
dephosphatation to enhance biogenic compounds’ removal in the wastewater
treatment plant with separated nitrification on fixed-film. The analysis was based
on the multi-variant simulations of the combined system: fixed film activated
sludge performance. Activated sludge ASIM 2d model related with the model
of pollutions transformations in fixed film was used. The results of exploitation
analyses were performed according to the input parameters: average daily rate
of wastewater, pH, COD values, total suspended solids, total Kjeldahl nitrogen,
nitrate nitrogen, total phosphorus and alkalinity. The results indicated that there
is a possibility of including fixed film in the activated sludge technology in order
to improve nitrogen and phosphorus removal from the wastewater. Nitrification
process will be performed in fixed-film, whereas nitrogen and phosphorus removal
from the wastewater will be performed in anoxic chambers which operate in the
activated sludge technology. Denitrifying dephosphatation process guarantees
the high level of total phosphorus reduction (81%), but only if the whole easily
decomposable substrate will be consumed by microorganisms in the anoxic
chamber and if enough nitrates will be present in the environment