Ethanol as a solvent, a precursor of titanium isopropoxide and a stabilizer of either hydrochloric acid or ammonium hydroxide was used to prepare a titanium dioxide aqueous solution. The aqueous solutions with different values of pH and the morphology of the resultant reaction of the nanoparticles of titanium dioxide were investigated. The X-ray diffraction showed that at low temperatures and with acidic solutions, rutile structures are more favorable to grow on titanium dioxide synthesized, while at low and average temperatures and with base solutions, anatase phase is more pronounced. The crystalline form and the re-confirmation of the crystallite size growth were observed by the scanning electron microscopy. The atomi
... Show MoreOne of the major problems facing the industrial utilities especially cooling towers is biofouling. Many techniques and measures have been taken and still continuing researches are under way. Biocides and water qualities were the main area of research for evaluation. Friendly biocides are preferable for controlling viable count and fungi, but many harmful still in use.
The main objective of this research work is to predict a relationship covering the concentration of Cl and Br – containing compounds as biocide and the performance.
It was concluded that the chlorophenol is the major effective biocide used (reduce it for about 80%, while bromophenol to about 65%) and that material although they are highly approved, but suffer pittin
تعد التحولات العمرانية من القضايا المهمة التي شغلت العاملين في حقل العمارة وتصميم المدن . وان مراكز المدن المقدسة الاسلامية قد تأثرت وبشكل واضح وكبير بالتحولات الناتجة عن ازدياد الحاجات الانسانية والتقدم الحضاري والتكنولوجي ( الغير مدروس ) . وتظهر مشكلة البحث بصورة جلية في عملية التطور والتوسع للمدن المقدسة التي تمر في مرحلة صعبة بالنسبة لنسيجها التقليدي من جراء ما اصابها من تمزق في نسيجها وتحولها الى نسيج
... Show MoreIt is often needed to have circuits that can display the decimal representation of a binary number and specifically in this paper on a 7-segment display. In this paper a circuit that can display the decimal equivalent of an n-bit binary number is designed and it’s behavior is described using Verilog Hardware Descriptive Language (HDL).
This HDL program is then used to configure an FPGA to implement the designed circuit.
Planning for a city with human identity considers the needs of human being that exist in the traditional cities where it was so easy creating place there, on the other hand, modern cities refuse these values and reduce the human characters of urban fabric elements , and the searching for the concept of " Urban Coherence " considers the knowledge about urban theory, especially Morphological attitudes finding three sides of making the coherence of dense urban fabric which are " Functional Complementarily , Formal Complementarily ,
Contextual complementarily “and the differentiation of these sides within the variety of spatial structural patterns between the organic type of traditional city and the gridiron type of modern city. To
... Show MoreConstructional Efficiency in architecture in general is one of the most important standard success for any structure and a measure of its continuity and relevance across time and space. Given the importance of Al-Ahwaar environment that owned the spatial, environmental, economic and social elements had a prominent impact in creation of architecture patterns form to create special architectural and structural environment, which had many qualities and ingredients that contributed to its continuity and existence over the years. From the premise that man and his environment is the main goal to any architectural style,
Thus the research problem focusing on the lack of clarity of the previous literatures in its st
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Asphalt Hot Mix (HMA) is mainly applied in highway construction in Iraq because of its economic advantage and easy maintenance. Various factors impact the performance of HMA in the field. It is one of the significant impacts on aggregate gradation. The Universal Specification for Roads and Bridges in Iraq (SCRB) limits the different types of asphalt layers and allows for designed tolerance aggregate gradation. It is quite hard for contractors in the present asphalt industries to achieve the required job mix because of sieves' control problems. This study focuses on the effects on the required specification performance of aggregate deviations by using original and modified asphalt binder with AC(40-50) and
... Show MoreThe influence of natural convection due to buoyancy on the laminar upwards air flow in a uniformly heated inclined circular cylinder has been experimentally studied. The investigation covered a wide range of Reynolds number (450≤Re≤2008), heat flux (95 ≤ q ≤ 898) W/m2, Rayligh number (1.1132×105 ≤ Ra ≤ 3.6982×105 ), with different angles of cylinder inclination α=0° (Horizontal), α=30°, α=60° (Inclined) and α=90° (Vertical).Results show that the heat transfer process improves as the angle of inclination moves from vertical to horizontal position. A general empirical equation for average Nusselt number Num as a function of Rayligh number Ra, Reynolds number Re and angle of inclination α was obtained.
Friction stir welding (FSW) is a relatively new welding process that may have significant
advantages compared to the fusion processes as follow: joining of conventionally non-fusion
weldable alloys, reduced distortion and improved mechanical properties of weldable alloys
joints due to the pure solid-state joining of metals. In this paper, a two-dimensional model
based on finite element analysis is used to study the thermal history and thermomechanical
process in the butt-welding of aluminum alloys. The model incorporates the mechanical
reaction of the tool and thermomechanical process of the welded material. The heat source
incorporated in the model involves the friction between the material and the probe and the
This work aims to analyze and study the bit performance in directional oil wells which leads to get experience about the drilled area by monitoring bit performance and analyzing its work. This study is concerned with Rumaila Oil Field by studying directional hole of one oil well with different angles of inclination. Drilling program was used in order to compare with used parameters (WOB, RPM and FR).in those holes. The effect of the drilling hydraulic system on the bit performance was studied as well as the hydraulic calculation can be done by using Excel program. This study suggests method which is used to predict the value of penetration rate by studying different formation type to choose the best drilling parameters t
... Show MoreTotal quality management considers one of the modern scientific entrances which practiced by productivity service organizations alike to provide appropriate quality required outputs according to the needs and desires of customers manage , enable the organization seeking to continue and grow in light of the increasing competition from the satisfy and provide the appropriate total quality management requirements whenever led to face risks that they may have in a manner in which they can be addressed and find ways to avoid them in the future when repeated. &n
... Show MoreThis paper deals with the using of Geographic Information Systems to build up analytical model to choose the best locations of new schools within the study area. This has been done by using satellite image of Baghdad city. Then multi themes digital maps were prepared to the study area. These can be used to update their data by using Geographic Information Systems software. Then, an analytical had been prepared to create the best probable locations, for new primary schools, depending on criteria, scientific technical specifications. Finally, we prepared layouts with geographical geometrical specifications for these proposed locations.
A study on the treatment and reuse of oily wastewater generated from the process of fuel oil treatment of gas turbine power plant was performed. The feasibility of using hollow fiber ultrafiltration (UF) membrane and reverse osmosis (RO) membrane type polyamide thin-film composite in a pilot plant was investigated. Three different variables: pressure (0.5, 1, 1.5 and 2 bars), oil content (10, 20, 30 and 40 ppm), and temperature (15, 20, 30 and 40 ᵒC) were employed in the UF process while TDS was kept constant at 150 ppm. Four different variables: pressure (5, 6, 7 and 8 bar), oil content (2.5, 5, 7.5 and 10 ppm), total dissolved solids (TDS) (100, 200,300 and 400 ppm), and temperature (15, 20, 30 and 40 ᵒC) were mani
... Show MoreNo-fines Concrete is a lightweight porous concrete produced by omitting sand from the traditional concrete mix. It helps replenish the groundwater aquifer by directly allowing precipitation to seep into the earth thanks to its wide pores. This work studied the influence of partially replacing cement with silica fume (SF) with percentages of 5, 8, and 10% on some properties of no-fine concrete made using recycled coarse aggregate. The natural coarse aggregate (NA) was replaced with 10%, 20%, and 30% by crushed reactive powder concrete waste volume as recycled aggregate (RA). The optimum percentage was 10% RA with 10% SF, which indicated a substantial improvement in the no-fine concrete's strength, dry density, and water a
... Show MoreThis paper presents a study of the geometrically non-linear vibrations of clamped circular plates with variable thickness by taking the effect of large amplitude motion. The maximum thickness is considered to be at the plate center and it is taken to be twice the value of thickness at the edge. The problem is solved by the numerical iteration procedure to obtain the results of vibration amplitudes up to twice the maximum plate thickness. The results are presented for the first two modes of vibration. The obtained results indicate
that increasing the ratio of thickness has the effect of increasing the nonlinear frequency and modify the corresponding mode shape.
Research aims to develop a novel technique for segmental beam fabrication using plain concrete blocks and externally bonded Carbon Fiber Reinforced Polymers Laminates (CFRP) as a main flexural reinforcement. Six beams designed an experimentally tested under two-point loadings. Several parameters included in the fabrication of segmental beam studied such as; bonding length of carbon fiber reinforced polymers, the surface-to-surface condition of concrete segments, interface condition of the bonding surface, and thickness of epoxy resin layers. Test results of the segmental beams specimens compared with that gained from testing reinforced concrete beam have similar dimensions for validations. The results show the effectiven
... Show MoreThis paper proposes improving the structure of the neural controller based on the identification model for nonlinear systems. The goal of this work is to employ the structure of the Modified Elman Neural Network (MENN) model into the NARMA-L2 structure instead of Multi-Layer Perceptron (MLP) model in order to construct a new hybrid neural structure that can be used as an identifier model and a nonlinear controller for the SISO linear or nonlinear systems. Two learning algorithms are used to adjust the parameters weight of the hybrid neural structure with its serial-parallel configuration; the first one is supervised learning algorithm based Back Propagation Algorithm (BPA) and the second one is an intelligent algorithm n
... Show MoreTo damp the low-frequency oscillations which occurred due to the disturbances in the electrical power system, the generators are equipped with Power System Stabilizer (PSS) that provide supplementary feedback stabilizing signals. The low-frequency oscillations in power system are classified as local mode oscillations, intra-area mode oscillation, and interarea mode oscillations. A suitable PSS model was selected considering the low frequencies oscillation in the inter-area mode based on conventional PSS and Fuzzy Logic Controller. Two types of (FIS) Mamdani and suggeno were considered in this paper. The software of the methods was executed using MATLAB R2015a package.
Asphaltene is a component class that may precipitate from petroleum as a highly viscous and sticky material that is likely to cause deposition problems in a reservoir, in production well, transportation, and in process plants. It is more important to locate the asphaltene precipitation conditions (precipitation pressure and temperature) before the occurring problem of asphaltene deposition to prevent it and eliminate the burden of high treatment costs of this problem if it happens. There are different models which are used in this flow assurance problem (asphaltene precipitation and deposition problem) and these models depend on experimental testing of asphaltene properties. In this study, the used model was equation of
... Show MoreIn this work, a simple and new method is proposed to simultaneously improve the physical layer security and the transmission performance of the optical orthogonal frequency division multiplexing system, by combining orthogonal frequency division multiplexing technique with chaotic theory principles. In the system, a 2-D chaotic map is employed. The introduced system replaces complex operations such as matrix multiplication with simple operations such as multiplexing and inverting. The system performance in terms of bit error rate (BER) and peak to average ratio (PAPR) is enhanced. The system is simulated using Optisystem15 with a MATLAB2016 and for different constellations. The simulation results showed that the BE
... Show MoreA new design concept for a percolator is developed which combine the simultaneous production of ammonia vapor plus the pumping of weak aqua ammonia liquid. The steady state desig was based on a balance between the hydrostatic driving head and the total single and two-phase pressure losses in the percolator system. To accomplish this, the results from modeling of the driving pressure and pressure losses, using the separated flow and drift flux methods were compared with the experimental measurements. The Chisholm's model was the best in predicting the measured flow rate versus water level for first stage with a maximum standard deviation of ± 10.1% and was adopted for the theoretical calculations. Parametric design studies that include t
... Show MoreThe aesthetic and architectural shapes of the beam-column elements may enhance the elements strength depending on the maximum and minimum bending moments effect. Therefore, the stability value of the non-linear taper member in concave configuration may be more efficient than linear taper or prismatic members. The modified stability functions will be obtained from the solution of the basic differential equation, where this basic differential equation depends on the non-linearity factor of the beam-column shape and the shape factor of the cross-sectional area. These two factors, multiplied by others, produce the modified shape factor, which affects the results of the basic differential equation solutions.
The aim of this research was to apply a numerical model capable of describing the thermal pollution in rivers. For this purpose a two-dimensional numerical model was applied for estimating temperature distribution in a river Momentum Conservation Equation and Thermal Energy Equation were used to describe the fdistribution and diffusion of temperature along the river subjected to thermal pollution point source. Furthermore the model incorporates the (k-e) turbulence model to calculate the distribution of turbulent viscosity The pressure distribution was determined using hydrostatic pressure equation. The partial differential equations were formalized and simplified to be solved using Alternative direction implicit- explicit method (ADI) w
... Show MoreAn approximate solution of the vibration of an elastically restrained, uniform and non-uniform beams with translational and rotational springs is obtained using Rayleigh-Ritz approach. The frequencies are presented for wide range of restrained parameters and some of these have been compared with those available in the published literature illustrating the accuracy and versatility of the approach. It is believed that the results present in this paper will be of use in design of beams, shaft, and piping under dynamics consideration.
Experiments were conducted to study the local and average heat transfer by mixed convection for hydrodynamically fully developed but thermally developing laminar air flow in horizontal circular cylinder. The experimental setup using an aluminum cylinder as test section with 30 mm inside diameter and 900 mm heated length (L/D=30), is subjected to a constant wall heat flux boundary condition. The investigation covers Reynolds number range from (400 to 1600), heat flux varied from (60W/m² to 400W/m²)and by using an aluminum entrance section pipes (calming sections) having the same inside diameter as test section pipe but with variable lengths as entrance sections. The entrance sections included a long calming section of length 240 cm (L/D
... Show MoreThis paper includes study of performance of single cylinder, 4-stroke spark ignition engine
Ricardo E6, with variable compression ratio, spark timing and equivalence ratio, fueled with
supplementary hydrogen to gasoline.
The speed of 25 rps and higher useful compression ratio were chosen in studying the effect of
wide range of equivalence ratios and spark timing.
The results showed that HUCR for mixture of two fuels was (9:1). The brake power when
operated with gasoline was higher than when it was fueled with hydrogen alone, but when mixing
two fuels the brake power increased and became higher than that when working with gasoline to a
certain limit (the hydrogen volumetric ratio in the mixture reached 80%), after
This research study one of the specialized buildings related to culture, and the cultural activity considered as the basic cause of its architecture presencing. The main role of these centers is to spread culture and to provide ways of natural cultural communication among various societies. These societies differ in expressing culture and methods of cultural activity performance, as the cultural act, with its different levels, connects with each society s civilizational codes and direct this act to meet the spiritual and material needs of the society in general and the person in particular. The difference between cultures had been reflected in the way of performing the cultural activity and the buildings needed for serving this activity
... Show MoreThe goal of the research is to develop a sustainable rating system for roadway projects in Iraq for all of the life cycle stages of the projects which are (planning, design, construction and operation and maintenance). This paper investigates the criteria and its weightings of the suggested roadway rating system depending on sustainable planning activities. The methodology started in suggesting a group of sustainable criteria for planning stage and then suggesting weights from (1-5) points for each one of it. After that data were collected by using a closed questionnaire directed to the roadway experts group in order to verify the criteria weightings based on the relative importance of the roadway related impacts
... Show MoreThe current practice in Iraq showed that satisfactory sealing of joints for concrete structures is not always achieved. The poor quality of local sealants is usually considered the main cause of such improper performance. The purpose of this work, therefore, is to review and investigate the factors affecting the performance of thermoplastic hot-applied joint sealers which are mostly used in horizontal joints of rigid pavements as shown by the literature reviewed in this study. The impact of different compositions including asphalt cement, reclaimed rubber, mineral filler, fiberglass and, polyvinyl chloride, together with the effect of manufacturing procedures and materials' percentage are studied. Sealant physical proper
... Show MoreWater level rise as well as inundation to gypseous soil medium can lead to a substantial loss of volume of the soil, with or without adding load. Macromechanical behavior of gypseous sandy soils using particle image velocimetry (PIV) is yet to be studied, with a particular emphasis on patterns of collapse. These unique patterns have given attention to researchers on deformable soils, but the difficulties of gypseous sandy soil still need to be addressed. Consequently, this study aims to quantify the local-scale displacement fields and patterns of failure of gypseous sand interacting with rigid strip foundations under static stress under comparison, emphasizing wetting due to rising the water table and the dry state using
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