In this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperatur

New, simple and sensitive batch and nFIA spectrophotometric methods for the determination of Vancomycin Hydrochloride in pure form and in pharmaceutical preparations were proposed, These method's were based on diazotization and coupling reaction between Vancomycin Hydrochloride and diazotized O-nitroaniline in alkaline medium to form Orange water-soluble dye that is stable and has a maximum absorbance at 465nm. Acalibration graph shows that aBeer's law is obeyed over the concentration range of 0.8-60 and 5-400 μg.mL-1 of Vancomycin Hydrochloride with detection limit's of 0.16 and 1.666 μg.mL-1 of Vancomycin Hydrochloride for batch and nFIA methods, respectively. The FIA procedure sample throughput was 80 h-1. All different chemicals an

The drought is a globally phenomenon, its influence will convert large parts of Middle East and North Africa (MENA) region into hot dry deserts under the expectations of the climate change scenarios. Climate limitations, soil erosion affected by weather properties such as unequally and limited rainfall; temperature changing and wind, unsuitable irrigation techniques, excessive grazing, agricultural expansion against to the natural habitats, extensively clearance of natural vegetation, and soil salinity had all contributed to land degradation, reduced water supplies, and limited agricultural production in Iraq. It is estimated that nearly 54.3 % of Iraq's area is threatened by desertification problems.
In this research, for Iraq the Cl

يهدف البحث إلى تقييم الكفاءة الوظيفية لمؤسسات التعليم الأهلي في أداء وظيفتها بمستوى عالٍ لتشبع حاجة سكان المدينة الذين فضّلوا التعليم الأهلي على التعليم داخل المؤسسات الحكومية مما أدى إلى انتشارها، وصولا إلى أهم الآثار المترتبة على ذلك الانتشار إذ نافست فيه مؤسسات التعليم الحكومي، بل وتنافست المؤسسات الأهلية فيما بينها لتقديم أفضل خدمة تعليمية للصراع من أجل البقاء، وتهدف أيضا إلى  إظهار الوجه السلبي ا

A spectrophotometric method has been proposed for the determination of two drugs containing phenol group [phenylephrine hydrochloride (PHP) and salbutamol sulphate (SLB)] in pharmaceutical dosage forms. The method is based on the diazotization reaction of metoclopramide hydrochloride (MCP) and coupling of the diazotized reagent with drugs in alkaline medium to give intense orange colored product (?max at 470 nm for each of PHP and SLB). Variable parameters such as temperature, reaction time and concentration of the reactants have been analyzed and optimized. Under the proposed optimum condition, Beer’s law was obeyed in the concentration range of 1-32 and 1-14 ?g mL-1 for PHP and SLB, respectively. The limit of detection (LOD) and l

Adsorption is a simplified new way, easy application , economical and environmentally friendly. In which the use of certain types of plants to remove or reduce toxic heavy metals from water. The current study involved the use of a non-living biomass as a powder for local plant available in the Iraqi environment is Phragmites australis .This the study showed the high ability of this plant to remove cadmium and lead ions from the aqueous solutions within variable experimental factors by column bed method which were used to test different sizes of plant powder were (500.1000, 1500 and 2000) μm . These sizes treated with initial concentration of Cd(II), Pb(II) was 25ppm , separately To test the optimum size for maximum adsorption and was 10

This paper presents a proposed neural network algorithm to solve the shortest path problem (SPP) for communication routing. The solution extends the traditional recurrent Hopfield architecture introducing the optimal routing for any request by choosing single and multi link path node-to-node traffic to minimize the loss. This suggested neural network algorithm implemented by using 20-nodes network example. The result shows that a clear convergence can be achieved by 95% valid convergence (about 361 optimal routes from 380-pairs). Additionally computation performance is also mentioned at the expense of slightly worse results.

Objectives: During the COVID-19 pandemic, dentists have had to work under stressful conditions due to the nature of their work. Personal protection equipment (PPE) has become mandatory for work in the dentistry field. This study aimed to examine dentists' practices and attitudes regarding the use of PPE and the associated drawbacks and cost implications during the pandemic.

Methods: A questionnaire-based survey was used and was divided into five sections dedicated to collect demographic variables and to examine the dentists' practices, attitudes toward PPE, drawbacks, and cost of using PPE. Mann-Whitney U and Kruskal-Wallis tests were used to compare different sections of