The Esterification kinetics of acetic acid with ethanol in the presence of sulfuric acid as a homogenous catalyst was studied with isothermal batch experiments at 50-60°C and at a different molar ratio of ethanol to acetic acid [EtOH/Ac]. Investigation of kinetics of the reaction indicated that the low of [EtOH/Ac] molar ratio is favored for esterification reaction, this is due to the reaction is catalyzed by acid. The maximum conversion, approximately 80% was obtained at 60°C for molar ratio of 10 EtOH/Ac. It was found that increasing temperature of the reaction, increases the rate constant and conversion at a certain mole ratio, that is due to the esterification is exothermic. Activity coefficients were calculated using UNIFAC program. Results showed deviation in activation energy in the non-ideal system of about 20% this is due to the polarities of water and ethanol compared to the non-polar ethyl acetate this dissimilarity leading to strong non- ideal behavior. The homogenous reaction has been described with simple power-law model. The chemical equilibrium combustion calculated form the kinetic model in agreement with the measured chemical equilibrium.
Each of the languages possesses a set of phenomena that researchers in its sciences should stop at to explain the secrets of this language, including the phenomenon of idiomatic expression. Perhaps this phenomenon may constitute an obstacle to non-native speakers of the language or even the native speakers themselves. The Arabic language is full of these expressions, Which needs us to dedicate its own studies to it so that we can collect it in a dictionary that includes and collects it with explanation and interpretation of its semantics
There is no doubt that the narrative form is a mixture of many elements that it
becomes so hard to differentiate between them. Thus, to differentiate between those
elements we must understand the job of every element; and that is the structure of narrative
form in the artistic frame of the old Arabic poem.
Poetry, as the readers confirm, is strongly related to a lot of arts. The rhetorical
form is related to the art of drawing and photography, the rhythm- the core of poetry- is
related to music, its structure to the art of architecture, its tension to drama as it consist of
internal conflict between its elements and ingredients, and the poetry has a narrative
element which relates it to the art of narration and it
This paper deals with one of important topics that serve the art movement music, which is looking at the stairs of Arab music in the process of reaching to the directory musical on the subject of so-called (Photo by stairs music) and that by comparing the method used previously and the proposed rules reached by the researcher and received the patent invention, the method is easier for the musician and the author in a directory of peace Arab music when used on grades and half grades voice, and to achieve its objectives researcher dealt with the problem that is determined by the multitude of stairs leading Arab and the difficulty of keeping its catalog of music, and for being an anchor and pillar of the music was taken up and put her impor
... Show MoreThe essential objective of this study presents a analyzes of the combination of reality and fantasy in three dramas of Spanish author Alejandro Casona. "Trees die standing" (premiered in Buenos Aires in 1949), “Prohibited suicide in spring” (premiered in Mexico in 1937) and "The boat without fisherman" (premiered in Buenos Aires in 1945).
The first part is an introduction about the biography of Spanish author Alejandro Casona that will allow us to understand some peculiarities of his work in relation to the social historical context of his time.
In the second part of this study we have analyzed elements of reality and fantasy in the th
... Show Moreيسلط هذا البحث الضوء على ظاهرة لغوية، والتي يطلق عليها تسمية "التضاد". يبين هذا البحث مفهوم هذه الظاهرة، خصائصها، أنواعها، وأسبابها، في اللغتين الساميتين: السريانية والعبرية. حيث تم اعتماد المنهج المقارن في دراسة هذه الظاهرة اللغوية وتبيان وجوه التشابه واالختالف في ماهية هذا النوع من المفردات، أي األضداد، في اللغتين: السريانية والعبرية. ويشير البحث إلى نوعين من التضاد وهما: التضاد الذي يكون بين مفردتين مستقل
... Show Moreהמחקר מתייחס לתופעת ההקטנה משני ענפים את הסימנטיקה והמורפופונולוגיה בשפה העברית, ומנסה ליגלוי את המשמעות בתוך ההקשר של צורות ההקטנה לדוגמאות מן התורה טקסטים מחדשות, שירה וסיפורים, הרי שחלק מהמשמעויות של מבנה הפלט עומדות בניגוד למשמעויות הבסיס או הדרגה במשמעות, כך מביעות על (הקטנה, חיבה, או זלזול) שרובן לא התקיימו בעברית הקלאסית, מצד אחר המחקר בדק במבנים המורפולוגיים במייוחד (המשקלים של צורת ההקטנה) ומבחין את
... Show Moreالشرط المانع من التأجير هو عبارة عن قيد اتفاقي يرد في عقد الإيجار مقتضاه تقييد حرية المستأجر من التصرف في حقه بالإيجار من الباطن أو التنازل عن الإيجار إلا بموافقة المؤجر.وهو بذلك قيد إرادي يرد على حرية المستأجر في التصرف بحقه الناشئ عن عقد الإيجار استثناءً من الأصل العام، وهذا الشرط أما ان يرد على منع المستأجر من التنازل عن الإيجار إلى الغير أو الإيجار إلى الغير من الباطن أو كلا الحالتين، وهو أما أن يظهر بصورة
... Show Moreيعد الرثاء أساساً من أسس الموروث الشعري العربي، وهو باب من أبواب الشعر الرئيسة. وقد وجد الإنسان فيه بغيته في التعبير عن مكنون نفسه ساعة تكتظ بالألم، ومنفذاً يخرج منه لواعجه وأشجانه إلى الخارج في شكل تعبيري يحرر الدمعة، ويعاتب الموت. والرثاء غرض متطور ينمو مع نمو المجتمع والحياة ويسجل التغيير الذي يحصل في كل مرحلة من مراحل التاريخ، وهو نتيجة مهمة من نتائج اصطدام الشاعر بالحياة والأحداث. لهذا وقع اختياري على شع
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