The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i

This experiment was carried out in the field of botanical garden which belongs to Biologi
Department , College of Education (Ibn Al-Haitham), University of Baghdad during the
growing season 2009-2010.The experiment was designed to study the effect 5 concentrations
of Gibberellic acid(GA3)( 25,50,75,100and125mg.L
-1
) and 2 levels of NPK (17:17:17)
fertilizer (200 and 400 Kg.ha
-1
) and their interaction on the rates of absorption and transport
of some macronutrient elements in two varieties of chamomile plant ( Local variety ,
Matricaria chamomilla L. and German variety , Matricaria recutitia L.) . Randomized
Complete Block Design (RCBD) was used with 3 replicates for each treatment .Control plants

The aim of the present study is to investigate and compare the efficacy of L-carnitine, multivitamins and their combination therapies on semen characteristics in idiopathic male infertility. Idiophathic infertile patients were randomly divided into three groups who had received three different treatment regimens for three months: group A (45 patients) has received 2 grams daily of L-carnitine alone; group B (55 patients) had received the combination of  L-carnitine (2 grams daily) plus one tablet daily of multivitamins (Stresstabs^®); and group C (29 patients) had received one tablet daily of multivitamins alone. The study was started on 1/11/2009 and completed on 31/3/2010 and performed at Rizgari Teaching Hospital in

This research was based on two pillars. The first is a comparison between of research done and the result of a particular  variable of research  indebendently in the united state, and second, knowledge and determine the effect of managers  practices on the contributions of personnel. The manager and staff are considered to be the most important elements in the organization and all of them  have a duty towards the others which governed by the relationship rules of procedure of the ministry researched, on the one  hand  and the interests of the organization and hence employees , whether executives  or employees within management formations that the availability of an acceptable level of good pract

The current study introduces a novel method for calculating the stability time by a new approach based on the conversion of degradation from the conductivity curve results obtained by the conventional method. The stability time calculated by the novel method is shorter than the time measured by the conventional method. The stability time in the novel method can be calculated by the endpoint of the tangency of the conversion curve with the tangent line. This point of tangency represents the stability time, as will be explained in detail. Still, it gives a clear and accurate envisage of the dehydrochlorination behavior and can be generalized to all types of polyvinyl chloride compared to the stability time measured by conventional ones based

Abstract

The aim of the current research is to prepare an integrated learning program based on mathematics standards for the next generation of the NYS and to investigate its impact on the development of the teaching performance of middle school mathematics teachers and the future thinking skills of their students. To achieve the objectives of the research, the researcher prepared a list of mathematics standards for the next generation, which were derived from a list of standards. He also prepared a list of the teaching competencies required for middle school mathematics teachers in light of the list of standards, as well as clarified the foundations of the training program and its objectives and the mathematical

Volunteerism is an element included in many human cultures. It represents a positive cooperative act between individuals and groups. It expresses the social value systems. As a social phenomenon, it develops in societies according to innumerous circumstances and conditions. This study uses a functional approach that assumes that volunteering performs six functions for volunteers. Namely, we assume that volunteering (1) creates a sense of protection (2) meets significant cultural values (3) improves professional status of volunteers, (4) strengthens their social relationships, (5) helps them achieve a better understanding of life, and finally, (6) enhances their outlook and self-esteem. The central aim of the study is to discuss these fun

The Child is the first sedum for the human society performing, and we deal in our
research to explain the nature of the mutual relations in between the form and the medicine
social caring foundation. So the motherhood and the childhood nowadays become the most
dedicated in the researchers works, whom interesting in the social affairs, and that whom
work in the medicine field as scientists.
So the child is the future man and must be in wright body construction that need to great
care and interest to make him wright mind through capability of performing anything support
to him.
In our research we deal with the main factors in which lead to infect the child by the
creative malfunction, like the environmental and m

Background: Diarrheal diseases are still a major public health problem especially in developing countries, due to their high morbidity & mortality rates, moreover the lagest
number of deaths with diarrheal diseases are due to persistent diarrheal states.We attemted to evaluate the size of the problem in our infants, and assess risk factors & outcome.
Methods: A retrospective study was performed in Al-Kadhemya teaching hospital, to evaluate diarrheal cases in under 2 years of age children , admitted to hospital during the period (Dec. 1991- Dec. 2001), from a total of 863, chronic diarrheal cases formed 286 (33.14%) that were evaluated for certain variables; epidemiology & risk factors etiology ,