Biosynthesis of nanoparticles has received considerable attention due to the growing need to develop environmentally benign nanoparticle synthesis processes that do not use toxic chemicals. Therefore, biosynthetic methods employing both biological agents such as bacteria and fungus or plant extracts have emerged as a simple and a viable alternative to chemical synthetic and physical method .It is well known that many microbes produce an organic material either intracellular or extracellular which is playing important role in the remediation of toxic metals through reduction of metal ions and acting as interesting Nano factories. As a result, in the present study Ag NPs were synthesized by two methods biosynthetic technique using supernatant of Corynebacterium glutamicum that isolated from soil and green synthesis method by using plant extracts of fresh green plants.Ag NPs which synthesized by two methods were investigated visually by monitoring the color shift of reaction mixture from pale yellow to brown color, UV-Visible spectrophotometer was used to measure maximum absorbance of synthesized Ag NPs. The nanoparticles synthesized from Corynebacterium glutamicum exhibited maximum antimicrobial activity against selected pathogenic and environmental strains more than Ag NPs synthesized by green synthesis method from Spinacia oleracea, Malva parviflora and Eruca sativa. plant extracts
Introduction: This study aimed to assess the color change of human teeth with artificial enamel white spot lesions (WSLs) after sandblasting with bioactive glass, resin infiltration, and microabrasion and to test color stability after pH cycling. Methods: Fifty extracted human mandibular first molars were randomly assigned into five groups: Sound, WSLs (untreated), and WSLs sandblasted with bioactive glass (Sylc), WSLs treated by resin infiltration (ICON), and WSLs treated by microabrasion (Opalustre), respectively. All specimens underwent a pH cycling procedure. The color parameters for each specimen were assessed using an Easyshade dental spectrophotometer at different time stages then the color changes (ΔE) were calculated. Results: The
... Show MoreThis study focused on the various forms of violence that aged people encounter in their late life, the significance of taking measures that enhance not only the welfare for aged people but also the influence of early stage of life and how the old age effects on people experience throughout their live. Further, the importance of raising the awareness among communities to the extent of seriousness of old age in order to teach children the right habits and traditions, which are faded away over time. The researcher indicated that raising the avenues of collaboration among home members, social organization, and all governmental facilities will support and provide a good treatment for this group of people.
Experimental work has been performed on three capillary tubes of different lengths and diameters using R-12 and R-134a. The test also studies the effect of discharge and speed of evaporator fan. The results clearly showed that refrigerant type and discharge significantly influence the temperature drop across the capillary tube. While the speed of evaporator fan has small effect. Experimental results showed that the temperature gradient for the two refrigerants are the same, but after approximatly one meter the temperature gradient of R-134a is steeper than R-12.
Social networking sites have become very popular since the beginning of the current decade and have become linked to our daily life. We follow the news, Analyses and opinions on the one issue in a way that attracts millions of users and the number grows every secon On Twitter, one of the most important social networking sites, all social groups rushed from the president to the last citizen to open accounts when they found themselves forced to do so . During the recent Gulf crisis, Twitter was buzzing with Twitter, which achieved the largest circulation globally. Instead of serving the issue and directing it to serve the Arab interest, most of the publications were on th |
The current study aims at identifying of the differences of life quality level for the academic instructors at Omar Al-Mukhtar University / Libya according to the city variable that the instructor belong to ( Libya, Iraq, Egypt ), and also according to gender Variable (Male - Female),To achieve the aims of study ,the researcher chose a sample consists of (210) instructors ( 170 males and 40 females) from four colleges at Omar Al- Mukhtar University/ Darna . The researcher built the scale of life quality which consists of (42) items in last version . The researcher has conducted the validity and reliability of the scale. and by using Analysis of Variance via (SPSS program). The research reaches the following results : 1-The life quality o
... Show Moreان نجاح رياض الاطفال في تحقيق اهدافها يتوقف الى حد كبير على معلمة الروضة التي تزود الطفل بالخبرات ، فهي تمثل الام البديلة للطفل ، وتقع على عاتقها مسؤوليات نفسية واجتماعية واخلاقية نحو اطفال الروضة ، لدلك فان معلمة الروضة تقوم بعدة ادوار في رياض الاطفال ، فهي ممثلة لقيم المجتمع وتراثه التي تسعى الى غرسها في الطفل .
وعليه فان ليس كل من تتقدم للعمل في رياض الاطفال تصلح ان تكون معلمة ناجح
... Show Moreيحتل موضوع الاستهلاك اهمية كبيرة في الدراسات الاقتصادية في حالتي السلم والحرب وذلك لارتباط هذا الموضوع بالانسان والمجتمع ولكونه احد مؤشرات مستوى الرفاهية الاقتصادية والاجتماعية وتزداد اهمية ضبط حركة هذا المتغير السلوكي والكمي في زمن الحرب اكثر مما هو عليه في حالة السلم، في هذا البحث تم استخدام بيانات احصائية عن الانفاق الاستهلاكي الخاص ونصيب الفرد من الدخل القومي اضافة الى الرقم القياسي لاسعار المس
... Show MoreThin films of Mn2O3 doped with Cu have been fabricated using the simplest and cheapest chemical spray pyrolysis technique onto a glass substrate heated up to 250 oC. Transmittance and absorptance spectra were studied in the wavelength range (300 -1100) nm. The average transmittance at low energy was about 60% and decrease with Cu doping, Optical constants like refractive index, extinction coefficient and dielectric constants (εr), (εi) are calculated and correlated with doping process.