For many problems in Physics and Computational Fluid Dynamics (CFD), providing an accurate approximation of derivatives is a challenging task. This paper presents a class of high order numerical schemes for approximating the first derivative. These approximations are derived based on solving a special system of equations with some unknown coefficients. The construction method provides numerous types of schemes with different orders of accuracy. The accuracy of each scheme is analyzed by using Fourier analysis, which illustrates the dispersion and dissipation of the scheme. The polynomial technique is used to verify the order of accuracy of the proposed schemes by obtaining the error terms. Dispersion and dissipation errors are calculated and compared to show the features of high order schemes. Furthermore, there is a plan to study the stability and accuracy properties of the present schemes and apply them to standard systems of time dependent partial differential equations in CFD.
Bioethanol produced from lignocellulose feedstock is a renewable substitute to declining fossil fuels. Pretreatment using ultrasound assisted alkaline was investigated to enhance the enzyme digestibility of waste paper. The pretreatment was conducted over a wide range of conditions including waste paper concentrations of 1-5%, reaction time of 10-30 min and temperatures of 30-70°C. The optimum conditions were 4 % substrate loading with 25 min treatment time at 60°C where maximum reducing sugar obtained was 1.89 g/L. Hydrolysis process was conducted with a crude cellulolytic enzymes produced by Cellulomonas uda (PTCC 1259).The maximum amount of sugar released and hydrolysis efficiency were 20.92 g/L and 78.4 %, respectively. Sugars
... Show MoreAbstract: Objectives: The lowest dose of bromocriptine, necessary for suppression of lactation in rats, was estimated in this investigation. Methodology: Fifty healthy lactating rats were treated with different doses of bromocriptine. Cessation of lactation was assessed clinically and histologically. Results: Revealed that the lowest dose capable of lactation suppression is 4 mg bromocriptine / kg body wt. / day. It is very important to know the exact dose, which can suppress lactation in rats because these laboratory animals are commonly employed in experiments concerning this topic. Key words: Bromoci
Numerous regions in the city of Baghdad experience the congestion and traffic problems. Due to the religious and economic significance, Al-Kadhimiya city (inside the metropolitan range of Baghdad) was chosen as study area. The data gathering stage was separated into two branches: the questionnaire method which is utilized to estimate the traffic volumes for the chosen roads and field data collection method which included video recording and manual counting for the volumes entering the selected signal intersections. The stage of analysis and evaluation for the seventeen urban roads, one highway, and three intersections was performed by HCS-2000 software.The presented work plots a system for assessing the level of service
... Show MoreThe Ant System Algorithm (ASA) is a member of the ant colony algorithms family in swarm intelligence methods (part of the Artificial Intelligence field), which is based on the behavior of ants seeking a path and a source of food in their colonies. The aim of This algorithm is to search for an optimal solution for Combinational Optimization Problems (COP) for which is extremely difficult to find solution using the classical methods like linear and non-linear programming methods.
The Ant System Algorithm was used in the management of water resources field in Iraq, specifically for Haditha dam which is one of the most important dams in Iraq. The target is to find out an efficient management system for
... Show MoreIraq is located near the northern tip of the Arabian plate, which is advancing northwards relative to the Eurasian plate, and is predictably, a tectonically active country. Seismic activity in Iraq increased significantly during the last decade. So structural and geotechnical engineers have been giving increasing attention to the design of buildings for earthquake resistance. Dynamic properties play a vital role in the design of structures subjected to seismic load. The main objective of this study is to prepare a data base for the dynamic properties of different soils in seismic active zones in Iraq using the results of cross hole and down hole tests. From the data base collected it has been observed that the average ve
... Show MoreIf feminist philosophy in the context of feminist research focuses on how to produce an alternative knowledge and culture for women and forming anew awareness of their roles in the face of prevailing misconceptions then the topic of Islamic feminism is presented as a philosophical topic in the field of human knowledge to discuss how to produce an alternative knowledge of traditional knowledge prevailing in patriarchal societies to restore the balance of power and authority in the relationship between the sexes to create an effective feminist role in advocating for and defending womenś issues to achieve this Islamic feminism sought to establish an Islamic epistemology .
Objective: Econazole nitrate (ECZ) is one of the triazole antifungal drugs with poor aqueous solubility and dissolution rate; there is a need for enhancement of solubility. Therefore; inclusion complexation with β cyclodextrin (βCD) was performed. Methods: In this study kneading method and co-evaporation method of preparation of inclusion complex between βCD and ECZ using two molar ratios of βCD. The solubility of these complexes in isotonic saline solution and distilled water was studied. Complexes prepared by kneading method were used for the preparation of different ophthalmic gel formulas using carbomer (CB) and sodium carboxymethylcellulose (sod CMC) as a gelling agent. The release profile and the rheological behaviour of the gel w
... Show MoreBackground: The stethoscope is a tool that doctors use daily in the examination of patients and it can take part in the transmission of health care-associated infections. In a single day it may come in direct contact with multiple patients and the intra hospital environment may be contaminated by various type of bacteria and possibly transmit to others.
Objective:- The study was to know the attitude and knowledge about the stethoscope hygiene behavior among physicians and to determine the types of bacterial agents that can contaminate stethoscopes.
Type of the study: The study was a cross-sectional study
Metho
... Show MoreCopper Zinc Sulphide (Cu0.5Zn0.5S) alloy and thin films were fabricated in a vacuum. Nano crystallized (CZS) film with thick 450±20 nm was deposit at substrates glasses using thermal evaporation technique below ~ 2 × 10− 5 mbar vacuum to investigated the films structural, morphological and optical properties depended on annealing temperatures ( as-deposited, 423, 523 and 623) K for one hour. The influences annealed temperature on structurally besides morphologically characteristics on these films were investigated using XRD and AFM respectively. XRD confirms the formation a mixed hexagonal phase of CuS-ZnS in (102) direction with polycrystalline in nature having very fine crystallites size varying from (5.5-13.09) nm. AFM analys
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