A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.
The current research aims to validate the Effect of technical innovation on human resources management ambidexterity through job embeddedness. The current research was done in Al-Etihad Food Industries Co. Ltd. And within the industrial environment, the research was designed according to the descriptive research. And to achieve the main goal of the research above, the researcher used the questionnaire as a key instrument to collect data through the views of a sample of managers, and employees at the senior, middle and executive management level. The research sample reached (107) individuals, the data were analysed using the statistical packages (SPSS v. 26) and ( SMART PLS v 3. 3. 8) the group of statistical
... Show MoreNuclear shell model is adopted to calculate the electric quadrupole moments for some Calcium isotopes 20Ca (N = 21, 23, 25, and 27) in the fp shell. The wave function is generated using a two body effective interaction fpd6 and fp space model. The one body density matrix elements (OBDM) are calculated for these isotopes using the NuShellX@MSU code. The effect of the core-polarizations was taken through the theory microscopic by taking the set of the effective charges. The results for the quadrupole moments by using Bohr-Mottelson (B-M) effective charges are the best. The behavior of the form factors of some Calcium isotopes was studied by using Bohr-Mottelson (B-M) effective charges.
Seasonal variations of the species composition and abundance of Cladocera were studied in two stations at the end of the Tigris River and one station at the confluence of the Tigris with Euphrates area, at the beginning of the Shatt Al-Arab River in Al-Qurnah North of Basrah Province, from October 2015 to August 2016. Samples of zooplankton were collected by plankton net 100-µm. mesh size. The population density of Cladocera ranged between 1 Ind /m³ during summer and 211 Ind./m³ during winter at station 1 (Al-Jewaber Bridge). A total of 16 species of Cladocera belonging to 12 genera were recorded in the study. The average density of Cladocera ranged from 23.2 ind./m3 at Station 2 (Hamayon Bridge) to 53.7 Ind./m3
... Show MoreThis study sought to give a general picture of the organizations and formations of the ground forces of the Abbasid army in its first era, in preparation and armament and continuous development of the mechanisms to help maintain the moral and spiritual morale in the fighting.
Therefore, the caliphs' interest in building the army, organizing it, arming it, choosing competent leaders, and providing them with various weapons in terms of production and storage, as well as taking care of fortifying the cities and gaps in determination and determination, and embarked on construction and restoration, where amazing speed and acted according to the circumstances. During the first Abbasid era, there were significant developments in the military
Al- belenoby , Andalusian obscure poet .I choose to study poetic rhythm in this poetic and the appropriateness of with what rhythm touring in his self to give beautiful meaning raise to receiver to put the hands of continental placements creativity in poetry .I divided my research into ideas are presented in a sequential manner , I started researching with poetic rhyme than rhyme they represent the form of the poem, they represent the external form of the poem and their music that farm the general concept then the rhetorical styles that represent the internal form of the poem and it music that the listener works and enjoying it part by part all this led to the put the hands of the receiver placement creativity in Belenoby Poet.&nbs
... Show MoreWives generally and working wives especially may encounter in some
families forms of physical or psychological violence through all the
levels or whether it was a psychological intimidation or cursing and
insolence and detracting her human . value and the husband marries
another woman or uses physical abuse against her and beating and
sexual abuse of the wife are also included in this from . it is noticed that
the violent attitude of the husband may take one from or it may change
and alter with time for it might lead to the increase of the possibility of
violence to occur in different ways
The importance of this study comes out from the step that on which in
folds the problem of the use of the husband of vio
Abstract
The relationship between population and development is one of the most interrelated relations in contemporary societies. Therefore it is important focus on the demographic aspects of the population and its integration with developmental aspects, because the population is the makers of development and responsible for its success. The population composition and their qualitative composition are important factors in development. This change in age rate is because of demographic operations which lasted for long time. The change we are talking about is happing currently in Arab cou
... Show Moreيكتسب موضوع تدريب وتطوير العاملين أهمية بالغة في الظروف الاقتصادية الحالية التي تسودها مفاهيم وتوجهات جديدة كعولمة الاقتصاد ورأس المال المعرفي والفكري، وحيث صارت المعارف والمهارات والقابليات التي يمتلكها العاملون محركاً أساسياً باتجاه النجاح، وعنصراً مهماً في زيادة فاعلية منشأة الأعمال، وإدامة وجودها واستمرارها.
إن العاملين المدربين بشكل جيد على عمليات المنشأة وطبيعة المواد التي تستخدمها وإنتاجه
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