A novel fractal design scheme has been introduced in this paper to generate microstrip bandpass filter designs with miniaturized sizes for wireless applications. The presented fractal scheme is based on Minkowski-like prefractal geometry. The space-filling property and self-similarity of this fractal geometry has found to produce reduced size symmetrical structures corresponding to the successive iteration levels. The resulting filter designs are with sizes suitable for use in modern wireless communication systems. The performance of each of the generated bandpass filter structures up to the 2nd iteration has been analyzed using a method of moments (MoM) based software IE3D, which is widely adopted in microwave research and industry. Results show that these filters possess good transmission and return loss characteristics, besides the miniaturized sizes meeting the design specifications of most of wireless communication systems.
Accurate description of thermodynamic, structural, and electronic properties for bulk and surfaces of ceria (CeO2) necessitates the inclusion of the Hubbard parameter (U) in the density functional theory (DFT) calculations to precisely account for the strongly correlated 4f electrons. Such treatment is a daunting task when attempting to draw a potential energy surface for CeO2-catalyzed reaction. This is due to the inconsistent change in thermo-kinetics parameters of the reaction in reference to the variation in the U values. As an illustrative example, we investigate herein the discrepancy in activation and reaction energies for steps underlying the partial and full hydrogenation of acetylene over the CeO2(111) surface. Overall, we find th
... Show MoreAlloys of InxSe1-x were prepared by quenching technique with
different In content (x=10, 20, 30, and 40). Thin films of these alloys
were prepared using thermal evaporation technique under vacuum of
10-5 mbar on glass, at room temperature R.T with different
thicknesses (t=300, 500 and 700 nm). The X–ray diffraction
measurement for bulk InxSe1-x showed that all alloys have
polycrystalline structures and the peaks for x=10 identical with Se,
while for x=20, 30 and 40 were identical with the Se and InSe
standard peaks. The diffraction patterns of InxSe1-x thin film show
that with low In content (x=10, and 20) samples have semi
crystalline structure, The increase of indium content to x=30
decreases degree o
This study aimed to evaluate the effect of the COVID-19 outbreak on emergencies and pain among orthodontic patients attending a teaching hospital. The study was conducted among orthodontic patients receiving active orthodontic treatment or in a retention period at the College of Dentistry, University of Baghdad, Iraq. Their participation was voluntary, and they filled out an Arabic-translated questionnaire. The survey included general information, orthodontic problems, and a numerical rating scale for pain assessment. We used descriptive and inferential statistics (frequencies and intersecting frequencies), chi-square test and linear regression. Out of 75 orthodontic patients, only 54 (15 males and 39 females) were included in the s
... Show MoreSmoking has multiple effects on sex hormone , some of which are associated with important clinical implication .The present study was undertaken to investigate the biochemical changes of sex hormones associated with long standing cigarette smoking in 40 heavy smokers comparing with non- smoker and to correlate it with BMI for each .The sex hormones levels were determined by RIA technique . Atomic absorption technique was used to measure the zinc levels. The serum testosterone and estrogen levels of non – smoker group were 17.775ng\ml and 38.65ng\ml at p< 0.05, respectively .While the serum testosterone and estrogen levels of smoker group were 17.615n
... Show MoreThe current research aims to analyze the content and and make a comparison based on the theory of art education as an organized cognitive area D.B.A.E. The researcher started by making a comparison followed by analysing the content to design a philosophical framework for content. He used these steps as starting point to study the comparison and some elements of art education due to the modern theories at the third intermediate stage in both Iraq and Egypt in light of the art education trend as an organizing cognitive area.
Linde Type-A (LTA) zeolite was modified by adding lead sulfide into cavities of zeolite. The zeolite and zeolite –pbs were characterized by FTIR, XRD, AFM and SEM. The adsorption of congo red (CR) dye from aqueous solution by zeolite and zeolite – pbs were studied. Different parameters like contact time, temperature and concentration of (CR) dye were investigated. The results show that at contact time of 45, 30 min for maximum adsorption of (CR) dye onto zeolite and zeolite -pbs respectively were observed. The kinetic data was analyzed using pseudo-first-order and pseudo-second-order kinetic models. The adsorption kinetics of (CR) dye were fitted well with the pseudo-second-order k
... Show MoreObjective: To evaluate the changes in the surface quality of irreversible hydrocolloid impression material
hydrogum following disinfection with 0.525% sodium hypochlorite, 0.2% Chlorehexidine Gluconate, and 4%
Povidone Iodine.
Methodology: Forty specimens of alginate impression materials hydrogum were fabricated according to the
ISO 1563 and were divided into four groups according to the method of solution dipping: group 1: Dip in
0.525% sodium hypochlorite, group 2: Dip in 0.2% chlorhexidine gluconate, Group 3: Dip in 4% Povidone Iodine,
Group 4: No treatment with any solution (control group). Then the specimens were poured in type II stone.
Surface detail was determined using a stainless steel block in accordance w