In the present work the clathrate hydrate dissociation enthalpies of refrigerant R134a+ water system, and R134a + water + salt system were determined. The heat of dissociation of three types of aqueous salts solutions of NaCl, KBr and NaF at three concentrations (0.09, 0.17and 0.26) mol·kg−1 for each salt type, were enthalpy measured. The Clapeyron equation was used tocalculate heat of dissociation of experimental data for binary and ternary system.In order to find the effect of compressibility factor on heat dissociation enthalpy, the study was conducted by using equation of state proposed by Peng and Robinson Stryjek-Vera (PRSV). The obtained results of dissociation enthalpy for binary system were (143.8) kJ.mol-1 without gas compressibility factor (z) and (136.08) kJ.mol-1 with z where the variation between two values was (5.3%). For ternary system (R134a+ water +NaCl) at three concentrations of this salt, the calculated values were in the range of (146.7 - 154.1) kJ.mol-1without z and (138.02-145.14) kJ.mol-1with z where the variation rang between two values was (5.8-5.7) %. The other two types of salts given similar results within (0.886 - 0.129) % deviation rang about NaCl results without z and (0.818-0.149) % deviation rang with z values.
This study aims to know the degree of importance and the availability of the enhancing specifications of the educational process, and the way its objectives are achieved. Such a step involves using educational techniques, laying the selection foundations, knowing the methods of their employment and tracking the obstacles that limit this employment in teaching Arabic to non-native speakers. To achieve these objectives, the study followed a descriptive approach, and collected the necessary data through an integrated questionnaire prepared for the purpose of describing the phenomenon or topic. This approach was adopted, as it is characterized by being comprehensive, focuses on collecting data related and necessary to the topic under study.
... Show MoreSemiotics has been through wide experiences in various human sciences, especially in the fields of poetry, novel and myths. But its interest in the theatre and drama was much less and unique despite the richness of the theatrical connection as it is a probable field for the semiotic investigation which may require the semiotic approach in dealing with the theatrical and dramatic show during the two processes of: structural construction and deconstruction starting from a set of overlapping and interconnected texts inside the show, which can be limited in the text, then it would be difficult to semiotically cover all these complex and tricky texts. The theatre in its structural and aesthetic construction is c
... Show MoreThe research aimed to study the job satisfaction of the staff of the Federal board of supreme Audit and its relation to the effectiveness of their performance, The questionnaire was adopted as a main tool in the collection of data and information from a random sample of (54) employees of the Federal board of supreme Audit. In light of this, the data were collected and analyzed and the hypotheses were tested using the statistical program (SPSS).
The researchers reached a number of conclusions, the most important of which were: (1) the respondents' response to the variables of job satisfaction and the effectiveness of the performance were medium; (2) there was a significant relationship between job satisfaction and performance effe
... Show More This research aims to identify the economic design techniques and materials that can be used in the implementation of cosmetic supplements to the spaces of the dwelling. The research relied on the descriptive and analytical approach by describing and analyzing models of design techniques and materials that can be used in the production of cosmetic supplements in the interior spaces of the dwelling.
The results of the research concluded that the beautification of the spaces of the dwelling is one of the necessary and important pieces to add aesthetic touches to the internal spaces, and that the use of economic design techniques and materials contributes to the implementation of many pieces of complementary beautification of the
The author addresses the issue of the linguoculturological component in the process of teaching Russian to Arabic students, focuses on the peculiarities of the national character of students. The author also refers to the long-standing ties of Russian and Arab cultures, thus emphasizing the relevance of this aspect for the current state and situation of the Russian language in Arab countries.
Автор статьи обращается к вопросу лингвокультурологической составляющей в процессе преподавания русского языка арабским студентам, останавливается на особенностях национального хара
... Show MoreThis study presents the findings of a 3D finite element modeling on the performance of a single pile under various slenderness ratios (25, 50, 75, 100). These percentages were assigned to cover the most commonly configuration used in such kind of piles. The effect of the soil condition (dry and saturated) on the pile response was also investigated. The pile was modeled as a linear elastic, the surrounded dry soil layers were simulated by adopting a modified Mohr-Coulomb model, and the saturated soil layers were simulated by the modified UBCSAND model. The soil-pile interaction was represented by interface elements with a reduction factor (R) of 0.6 in the loose sand layer and 0.7 in t
To investigate the antiplaque and antigingivitis efficacy in addition to evaluating side effects and subjects’ perceptions of three commercially available mouthwashes.
This study was a double‐blind, parallel, and short‐term trial. A total of 75 dental students with biofilm‐induced gingivitis were included in the final analysis of the current study. Clinical parameters (plaque index and bleeding on probing) and the staining effect were measured at baseline and after 7 days. In addition, a VAS‐based assessment questionnaire was completed by the participants.
