حامد احمد, ندا حسن

كلية الزراعة-جامعة الخرطوم · السودان

Duma is a fermented honey drink commonly found in southern Sudan.Ethanol content of collected samples ranged from 4.3% to 10.2%, and total acidityranged from 0.73% to 1.08%, while volatile fatty acids were very low.Laboratory fermentation showed that duma fermentation is an alcoholicfermentation as shown by an increase in yeast count producing 8.25% ethanol. Thefermentation is also a lactic fermentation, which is indicated by the increase inlactic bacteria dropping the pH from 4.9 to 3.02. During the process total acidityincreased from 0.12% to 0.8%.Tentative identification of microorganisms showed that yeast isolates belonged toSchizosaccharomyces pombe, Schizosaccharomyces octosporus, andSaccharomyces cerevisiae, while lactic acid bacteria belonged to Lactobacillubrevis, L. fermentum, L. plantarum and Pediococcus damnosus.Microorganisms that were responsible for fermentation were used asstarter culture in laboratory fermentation. The result indicated thatfermentation by this method is faster than the traditionalfermentation. Metabolic products were characterized by an increase inethanol to 9.86% and a total acidity of 0.75%. The pH dropped from 4.7to 3.0, and volatile fatty acids were very low.Physiological studies have shown that yeast isolates were thermophilicand osmotolerant. With respect to salt tolerance, all isolates were ableto grow at 10% sodium chloride.

Abdullah Al-Musallam, Mohammed Maslehuddin, سيد عمران علي

كلية الهندسة-جامعة الملك فهد للبترول والمعادن · السعودية

The reduction in the useful-service life of concrete structures in the Arabian Gulf, due to chloride-induced reinforcement corrosion is of major concern to the construction industry in this region. There are several options available to minimize concrete deterioration due to reinforcement corrosion. Among these alternatives, the use of good quality concrete is the cheapest one. However, it is difficult to produce good quality concrete locally, as the available limestone aggregates are weak and highly absorptive. Therefore, there is a need to improve the quality of concrete by suitable adjustments in the mix design. Further, the performance of high quality concrete when exposed to thermal variations is not very well documented. This research was conducted to develop high quality concrete utilizing local aggregates. Three types of coarse aggregates, namely limestone aggregates from Abu-Hadriyah and Riyadh, and steel slag aggregates were selected to produce high quality concrete. The tensile strength and reinforcement corrosion of the high quality concrete produced using local aggregates were investigated. The data developed in this research indicate that the quality of aggregate has a significant effect on the corrosion resistance of concrete. The steel slag aggregate concrete showed better corrosion resistance and tensile strength followed by Riyadh and Abu-Hadriyah aggregate concretes. Exposure to the thermal variations reduced the corrosion resistance of reinforced concrete specimens prepared with the selected aggregates. The service life of the concrete prepared with the selected aggregates was predicted using two models, namely Bazant's mathematical model and Morinaga empirical formula. The highest service life was recorded in the concrete specimens prepared with steel slag aggregates, silica fume and steel fibers.

أحلام تيرشي , براهيمي صفيان, كاهينة بن سعيد

كلية الحقوق والعلوم السياسية-جامعة مولود معمري - تيزي وزو · الجزائر

إن تكريس حرية المنافسة يقتضي من المشرع تشغيل الحرية الاقتصادية بشكل صريح و إزالة جميع القيود، و يرتبط أيضا هذا التفعيل في حماية المستهلك و تحقيق الازدهار و توفير الرفاهية له، و لكن ظهرت عدة ممارسات مقيدة للمنافسة أدت إلى عرقلة الدولة لتحديد الأسعار في السوق و ذلك من اجل حماية المنافسة و المستهلك الذي يعتبر الطرف الأساسي و الضعيف في العملية الاستهلاكية، و لكن هذا التدخل قد جاء في مجالات ضيقة لا تكاد تخرج عن نطاق السلع و الخدمات ذات الاستهلاك الواسع.

حسن صالح, صفاء سلمان, نوار علي سعيد

كلية الطب البشري-جامعة تشرين · سوريا

ديهية قوداش, صارة مروان, نوارة حمليل

كلية الحقوق والعلوم السياسية-جامعة مولود معمري - تيزي وزو · الجزائر

صارة زرقان, ضريفة حدوش, فاطمة الزهراء أوذينة

معهد تسيير التقنيات الحضارية-جامعة محمد بوضياف - المسيلة · الجزائر

إن النشاط الإنساني كان دائما مولدا للنفايات، وكل مرحلة كان لها طريقة للمعالجة ومشاكلها الخاصة، لكن في القديم كان الحجم السكاني قليل وبالتالي تأثيره على البيئة ضئيل.نجحت العديد من الدول فى الاستفادة من مخلفات النفايات بصفة عامة عن طريق إعادة تدويرها وإنتاج مواد تقوم بنفس الدور مع توفير استغلال الموارد الطبيعية وتحقيق مبدأ الاستدامة للأجيال القادمة، وذلك في الوقت التى تعانى فيه الجزائر من وجود نسبة كبيرة من النفايات لا يتم استغلالها و تتسب فى العديد من المشاكل البيئية والصحية، وتحتاج في الفترة القادمة الى استهلاك الكثير من الموارد الطبيعية لاستخدامها فى انتاج مختلف المواد لتلبية حاجيات ومتطلبات السكان وتدوير هذه المخلفات والاستفادة من التجارب الغربية و استخدام المواد المعاد تدويرها ستساعد فى الاقلال من استهلاك الموارد الطبيعية المستخدمة فى إنتاج مواد جديدة والمحافظة عليها للأجيال القادمة .لقد صاحب التطور الذي شاهدته الجزائر خاصة في ميدان التصنيع والنمط المعيشي والاستهلاك تزايد في كمية النفايات المنزلية المنتجة حيث انتقل إنتاج الفرد للنفايات من220 كلغ/فرد/سنة، سنة 1980 إلى 380كلغ/فرد/سنة، سنة2012 هذا ما يشكل خطر حقيقي على البيئة، وهي تنتشر بشكل خطير داخل الأحياء الحضرية وعلى ضفاف الوديان والغابات... إلخ.اليوم أصبح من الضروري التقليص من التلوث، الاقتصاد في الطاقة، وتسير الموارد الطبيعية وذلك بتدوير النفايات التي أصبحت ضرورة ملحة لحماية الطبيعة، وإمكانية استمرار العيش بها مع تحقيق مبدأ الاستدامة.

أغليس بوزيد , ريمة عباسي, فتيحة عثماني

كلية الحقوق والعلوم السياسية-جامعة عبد الرحمان ميرة - بجاية · الجزائر

أمام الانفتاح الاقتصادي الذي شهدته الجزائر، والذي ترتب عنه شدة المنافسة بين الأعوان الاقتصاديين، حرص المشرع الجزائري على إيجاد إطار قانوني يضبط الممارسات التجارية، وذلك بحظر العديد من البيوع بمختلف صورها، والتي من شأنها أن تؤدي إلى الإخلال بتوازن السوق، بموجب القانون رقم 04-02 المحدد للقواعد المطبقة على الممارسات التجارية، من أجل قمع الممارسات التجارية غير الشرعية عن طريق آليات قانونية تتمثل في الجهات الإدارية والقضائية، وهذا لتحقيق الفعالية الاقتصادية.

Abdelhak Houadji, Hamane, Sofiane Behri

كلية التكنولوجيا-جامعة سعد دحلب - البليدة · الجزائر

George I. Za'rour, Nazeer Ahmad Chaudhry

الجامعة الأمريكية في بيروت · لبنان

شحادة مصطفي شحادة عبدة , عطا موسى عطا موسى

كلية الدراسات العليا -جامعة النجاح الوطنية · فلسطين

This study aimed at investigating the impact of using Environmental Approach on immediate and long-term achievement of ninth grade students in the subject of "human body systems" and on their self-concept. The study attempts to answer the following two main questions:First: what is the impact of using environmental approach in the achievement of ninth grade students in biology in the governmental schools belonging to the directorate of education in Tulkarm governorate?Second: what is the impact of using environmental approach in general self-concept of ninth grade students belonging to the directorate of education in Tulkarm governorate? To answer the questions of the study and test its hypotheses, the researcher conducted this study on a sample consists of (143) male and female students attending public schools belonging to the directorate of education in Tulkarm governorate. The students of the study were from four different schools: two for males and two for females.Two sections one for males and one for females were chosen randomly and these two sections represented the experimental sections. Two sections were taught by using environmental approach, whereas the other two sections were taught according to traditional method. A pre-knowledge test was applied its reliability checked by referees and validity was calculated by using Kuder- Richardson Formula No. (20), and its value was (0.85). A pre-self-concept test prepared by Swalha (1990) was applied before the experiment to make sure the even between the two groups. An achievement test also carried out in the subject of "human body systems".Referees checked reliability of the test and validity was calculated by using Kuder - Richardson Formula No. (20), and its value was (0.95) and by using Person Formula by Test- Retest Method was (0.87) and by Split-Halves Method was (0.90). The self-concept scale was applied to measure student's self-concept. Data were analyzed by using one and three ways analysis of variance on factor design (2x2x2) to test the study hypotheses.Findings:• There were statistical significant differences at (α = 0.01) level between the achievement of the ninth grade students in biology between experimental and control group in favor of experimental group which had used environmental approach.• There were statistical significant differences at (α = 0.01) level between scientific achievement mean of student-groups due to interaction between teaching method and sex, in favor of females in both groups.• There were no statistical significant differences at (α = 0.01) level between scientific achievement means due to: time, and sex.• There were no statistical significant differences at (α = 0.01) level between scientific achievement means due to interaction between: teaching method and time, time and sex, and between teaching method, time, and sex.• There were no statistical significant differences at (α = 0.01) level in general self-concept due to teaching method, time, and sex.• There were no statistical significant differences at (α = 0.01) level between achievement means of general self - concept due to interaction between: teaching method and time, teaching method and sex, time and sex, and between teaching method, time, and sex.Based on these findings, the researcher recommends that curricula designers, educational supervisors, trainers, teachers of science specially teachers of biology improving and using the environmental approach for its active impacts of the improvement of students achievements. He also calls for researchers to conduct further studies on other subjects in science especially in biology courses, for different levels to make benefit wider spread.