In this research an experimental study has done for testing the thermal performance of selective surfaces used in solar collectors for substrate of iron, galvanized iron and aluminum which are commercially available. The coating process for the samples has done in two ways, the electroplating and the chemical spray pyrolysis. The results of the thermal performance test of these samples are comparing with the thermal performance of a sample without paint and other paint with black paint without shines commercially available. For the electroplated samples, the performance study has done for different immersion time in plating bath, the
distance between electrical poles, the current density, and area ratio of the sample plated area to the nickel pole face area. The chemical sprayed pyrolysis samples, study has done for different coating times, atomizing gas pressures, distance between the aperture of atomizer and the sample and the paint mass flow rate. The results showed that the best performance of the iron's
samples is the sample which is coated with two layers. The first layer is of zinc done by electroplating where the time of plating is (2 min.) and the second layer is of black nickel done by electroplating, where the time is (20 min.), the distance between the poles is (6 cm), the current density is (0.15 A/dm2 ) and area ratio of the sample plated area to the nickel pole face area is equal to (1). The percentage of the increasing in heat storage of electroplating sample to galvanized iron sample without paint at the beginning of testing the performance of samples and at the end were (58.23%& 44.97%) respectively. For aluminum samples, the best performance was regarded for two samples electroplating sample and chemical spray pyrolysis sample. The best electroplating sample was coated with a layer of black nickel where the time of plating is (20 min.), the distance between the poles is (6 cm), the current density is (0.15 A/dm2) and area ratio of the sample plated area to the nickel pole face area is equal to (1). While the best chemical spray pyrolysis sample has been coated with a layer of black nickel where the time of plating is (16 sec.) and the distance between the aperture of the reservoir and the surface of the sample is (27 cm), the amount of flow is (4.8 ml / min.), the atomizing gas pressure is (1 bar) and temperature of the sample surface is (290 0C).
The problem of the tagged research (experimentation in the works of the artist Muhammad al-Kinani is an analytical study) dealt with the nature of the concept of experimentation and its work in the works of Muhammad al-Kinani. Which adopts the removal of the concept of style and artistic style and takes the experience away from the pattern of repetition The importance of the research comes through the identification of the materials founding the artistic work. The current research benefits the specialists in the field of arts from the students of studies with a new and renewed formulation of creativity. The research objectives shed light on the contemporary experiences of the artist Muhammad Al-Kinani and its importance in benefiting res
... Show MoreComputer modeling has been used to investing the Coulomb coupling parameter ?. The effects of the structure parameter K, grain charge Z, plasma density N, temperature dust grain Td, on the Coulomb coupling parameter had been studied. It was seen that the ? was increasing with increasing Z and N, and decrease with increasing K and T. Also the critical value of ? that the phase transfer of the plasma state from liquid to solid was studied.
The research dealt with the case stock repurchase policy of Emaar Real Estate Company one of listed companies in Dubai Stock exchange. The research has launched from the cognitive dimensions of repurchasing policy which took great concern in the literatures of financial management, and also this policy became as substitute for distributing the monitory profit in the last three decades in the international financial markets, but it did not get any importance in the Arab Markets such as that of the Arab Gulf in addition to the Iraqi Stock Exchange.
The research summarized a set of conclusions, the most important one was the consistence of analysis result with the test of the major two hypotheses (The first
... Show MorePraise be to God, Lord of the worlds, and prayers and peace be upon the best of the messengers, Muhammad, and all his family and companions. And after:
For when I had the pleasure of looking at the chapters of the Noble Qur’an, and its evident signs, my view fell on one of its brightest verses, and it is the Almighty saying: ﭽﯜ ﯝ ﯞ ﯟ ﯠ ﯡ ﯢ ﯣ ﯤ ﯥ ﯦ ﯧ ﯨﭼ (). The tag: (God’s Greatness in Creating a Hoopoe). The research methodology required that I divide it into four sections:
The first topic: an overview of birds.
The second topic: the characteristics and characteristics of hoopoe.
The third topic: the logic of the bird.
The fourth topic: Praise the bird.
This has relied in my research on
Negotiation is considered as one of the most important kinds of communication in the contemporary organizations, which depend on the important role of managerial information systems in providing necessary and suitable information for success of the negotiation process.
Accordingly, this study aims at measuring the extent of the variables effect of managerial information system in the negotiation process.
To achieve this study, two hypotheses were chosen; the first is the correlation relation and the second is the effect, and statistical means represented by correlation coefficient "Spearman" and (R2) were used.
A Number of conclusions were
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The research has discussed the public relations as dependent variable of its branch dimensions( confidence , commitment, control and satisfaction ) and the governmental service quality as independent variable of its branch dimensions (response, dependency, emphasis, tangibility and sympathy), and the research problem has represented by weakness of service quality presented to the customers dealing with company, which is observed via field co-existence of the researcher, where he observe that the quality presented in the company services, are inappropriate with the customers expectations level, also there is weakness of attention and recognition by the
The effectiveness and quality of legislation depend on the extent to which it relates to political , economic ,social ,geographical , health and moral realities , so the unrealistic legislation and its failure to address all the problems facing society make these legislation out of reality , this requires this legislation be able to regulate all aspects related to public health in society in exceptional circumstances such as cases of wars ,diseases and pandemics as outbreaks of corona virus in the word ,this study focuses on the effects of legislative omission on the effectiveness of the administration when performing its tasked in health administrative control in exceptional circumstances in light of spread of corona virus pandemic in Iraq
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This research attempt to explain the essential aspects of one important model in management of Bank risks , that is (stress testing) , which increase the concentrate on it resulting the negative affects of Global financial crisis that it accuar in 2008 to study the application possibilities in iraqian banks to enhancing the safety and financial soundness Becuase the classical tools in Risk management don’t give clear image on Banks ability in facing risks, hence the Basel committee on Banking supervision focusing in agreement of Basel 2,3 on stress testing when it doing the internal capital adequacy assessment process (ICAAP) .
To achieving the reseach obje
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This Study aimed to investigate the reality of the application of the degree of management practice by Walking Around, namely (discovery of facts, improvement of communication, motivation, development, creativity and feedback) and Its role in achieving organizational justice (procedural justice, distributive justice, Interactional Justice),The availability of the core principles of this system from the point of view of the senior management personnel in the Directorate of Anbar Education, and the importance of research in the philosophical rooting of the nature of the variables as a modern administrative terminology, the research dealt with a problem expressed by a number of intellectual and appl
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