حُضّرت أغشية سميكة بطريقة الطلاء الكيميائي من مساحيق أكسيد التنغستين النانوية مركب مصدر, بالطحن في مطحنة الكرات عالية الطاقة لفترات زمنية متعددة (1-18h) ، على ركائز زجاجية نظيفة تحتشر وطحرارية معينة (تم تغيير درجة الحرارة من 25°C إلى(350°C . دُرست الأغشية من حيث خصائصها التحسسية تجاه 100 ppm من بخار الإيثانول , باستخدام مميزات تيار-جهد (I-V) . تم استنتاج طاقة التنشيط Ea للأغشية المحضّرة من معادلة أرينيوس. وُثق تأثير الحجم الحبيبي والشروط الحرارية في الخصائص التحسسية للأغشية تجاه بخار الإيثانولو , كذلك الترابط بين الناقلية الكهربائية والحجم الحبيبي لمادة الأغشية. وأخيراً حُدد زمن الاستجابة للأغشية ذات الحجم الحبيبي 70.54 nm عند الدرجة 300°C.
Thick Films have been prepared by the chemical painting method from Tungsten Oxide nanopowdersas the source compound, which are prepared by milling in a high energy ball mill for variousspans of time (1-18h) on cleanedglasssubstratesunder limited thermal conditions. The temperature of the films have been changed from 25°C to 350°C. The films have been investigated for their sensing properties relating to 100 ppm ethanol vapor adsorption, using the (I–V) characteristics.The activation energy Ea for deposition films is deduced from the Arrhenius equation. The effect of the grain size and the thermal conditions on the sensing properties of the WO3thick films to ethanol vapor adsorption, as well as the correlations between The electrical conductivity of the WO3 thick films and the grain size of the material films are reported.The response time for films which have particle size about 70.54nm is defined at 300°C.
References used
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There are wide uses of tin oxide thin films, especially in the field of
transparent conductors, solar cells, gas sensors and piezoelectric materials.
Laser deposition is considered one of the most important techniques followed to
obtain these film
Mn doped tin oxide transparent conducting thin films were deposited at a
substrate temperature of 450°C by spray pyrolysis method. Structural
properties of the films were investigated as a function of various Mn-doping
levels (0, 1, 3, 5, 7 wt%) w
This study has been performed in Agriculture Research Directorated Labs, Ministry of
Science and Technology/Iraq, aimed to use different formulations of weaning food
contained different concentrations of black rice flour, brown rice, peas and oat c
يعد الميتانول و الإيتانول من أكثر المحلات شيوعاً، و بما أن درجة غليانها أقل من مئة
درجة مئوية فإنها تتطاير بشكل سريع. و على سبيل المثال، يستعمل الميتانول في تصنيع
الأصبغة و العقاقير و العطور.. و هو شديد السمية، لذلك من الضروري تطوير محسات لكشفه.
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In this work, multi-layer thin films (insulator - metal - insulator) were prepared on glass substrates. Where we deposited the following order of (zinc oxide - silver - zinc oxide) by magnetron sputtering of zinc oxide and vacuum thermal evaporation technique for silver.