تم في هذا البحث استخدام المحفز الجديد المصنع من تحميل دقائق البلاتين النانوية على سطح الصفائح النانوية للكرافين كمحفز ضوئي واختباره لدراسة التجزئة الضوئية لملوثات المياه وازالتها بشكل نهائي من مصادر المياه لما لها من تأثير سلبي على البيئة. حيث تم استخدام صبغة البروموفينول الأزرق كمثال على أحد الملوثات. في البدء تم التأكد من تحضير المحفز بالطريقة المستخدمة في طريقة العمل من خلال تشخيصه باستخدام عدد من التقنيات ومنها تقنية المجهر الالكتروني النافذ عالي الدقة، تقنية طاقة تشتت الاشعة السينية الطيفي عن طريق قياس الامتزاز/ الامتزاز باستخدام غاز النتروجين. كذلك تم قياس المساحة السطحية للمحفز المصنع، بالإضافة الى فحص التركيب الكريستال للمحفز باستخدام تقنية حيود الاشعة السينية. وبعد ان تم التأكد من التركيب النهائي للمحفز الضوئي تضمن الجزء الثاني من العمل دراسة قدرة المحفز المصنع على استخدامه في التجزئة الضوئية لصبغة البروموفينول الأزرق تحت الاشعة فوق البنفسجية حيث تم تحضير عدة تراكيز من صبغة البروموفينول الأزرق، تم تشعيع الصبغة بدون وجود المحفز ووجد بان التجزئة الضوئية لم تكن فعالة وبعد ذلك تم استخدام المحفز مع المحلول المائي للصبغة وبتركيز 15 جزء من المليون وأجريت التجارب باستخدام عدة اوزان من المحفز لتحديد افضل وزن يمكن استخدامه من المحفز في كمية محددة من محلول الصبغة ووجد ان 0.01 غرام من الصبغة لكل 250 ملليتر من المحلول المائي للصبغة هو افضل نسبة يمكن الحصول عليها. كما تم اختبار الوسط للتفاعل في الوسطين الحامضي والقاعدي ووجد ان تفكك الصبغة يزداد بشكل ملحوظ في الوسط القاعدي. تم اقتراح ميكانيكية التفاعل التي بينت ان تكون الجذور الحرة لها دور كبير في مهاجمة الاواصر المزدوجة في الصبغة.
In this work, porous silicon gas sensor hs been fabricated on n-type crystalline silicon (c-Si) wafers of (100) orientation denoted by n-PS using electrochemical etching (ECE) process at etching time 10 min and etching current density 40 mA/cm2. Deposition of the catalyst (Cu) is done by immersing porous silicon (PS) layer in solution consists of 3ml from (Cu) chloride with 4ml (HF) and 12ml (ethanol) and 1 ml (H2O2). The structural, morphological and gas sensing behavior of porous silicon has been studied. The formation of nanostructured silicon is confirmed by using X-ray diffraction (XRD) measurement as well as it shows the formation of an oxide silicon layer due to chemical reaction. Atomic force microscope for PS illustrates that the p
... Show MoreThe current research aims to describe the level of responsiveness and awareness of the officials of the General Company for Construction Industries to the indicators of the blue market strategy of (1. reduction 2. exclusion 3. increase 4. innovation) and the degree of prioritization according to their importance as well as the differences in the responses of the sample investigated according to the personal variables. As a main tool in the collection of data from the sample, which consisted of(34) officers (Associate, Manager, Section Manager, Division Officer) in the company being investigated, and computed mean, standard deviations, percentage weights,and test (x2 ) based on the SPSS. The research reached the following
... Show MoreAlPO4 catalysts supported with WO3 were prepared by impregnating the catalysts with ammonium metatungstate. The catalysts were checked by X-ray Diffraction (XRD), AFM, and SEM; also, the catalysts analysis was done by X-Ray (EDX). Finally, the N2 adsorption-desorption was used to measure the pore volume and surface area of the catalyst. The prepared catalyst has a surface area of 185.83 m2/g, pore volume of 0.645 cm3/g at a calcination temperature of 500°C for 3 hrs, and particle size of AlPO4 with an average of 35.36 nm. Transesterification of edible oil using WO3/AlPO4 was performed, it was observed that WO3/AlPO4 catalysts give high conversion of edible oil, and this is attributed to the high surface area, smaller particle size, and the
... Show MoreThis study relates to synthesis of bentonite-supported iron/copper nanoparticles through the biosynthesis method using eucalyptus plant leaf extract, which were then named E-Fe/Cu@B-NPs. The synthesised E-Fe/Cu@B-NPs were examined by a set of experiments involving a heterogeneous Fenton-like process that removed direct blue 15 (DB15) dye from wastewater. The resultant E-Fe/Cu@B-NPs were characterised by scanning electron microscopy, Brunauer–Emmet–Teller analysis, zeta potential analysis, Fourier transform infrared spectroscopy and atomic force microscopy. The operating parameters in batch experiments were optimised using Box–Behnken design. These parameters were pH, hydrogen peroxide (H2O2
... Show MoreBackground: The demand for better esthetic during orthodontic treatment has increased nowadays, so orthodontists starting using esthetic arch wires, brackets and ligatures.Tooth colored brackets were introduced in different types of materials. Sapphire ceramic brackets are one type of esthetic brackets and their color stability remains the main concern for the clinicians and patients at the same time. The present study design to evaluate the effect of three different staining materials (pepsi, black tea and cigarette smoke) on the stainability of sapphire ceramic brackets bonded with three types of light cure orthodontic adhesives which include: Resilience, Enlight and Transbond. Materials and Methods: The sample consisted of three hundre
... Show MoreAbstract: In this research, nanofibers have been prepared by using an electrospinning method. Three types of polymer (PVA, VC, PMMA) have been used with different concentration. The applied voltage and the gap length were changed. It was observed that VC is the best polymer than the other types of polymers.
Modern emerged technologies impose development and fabrication of miniatur-ized parts and devices in the micro- and nano-scale. Producing micro- and nano-featured structures requires nonconventional machining processes where con-ventional machining processes such as grinding, milling and eroding have failed. New emerging processes, such laser machining processes, are still fraught with almost invincible processes. Micro-/nano-machining are the pro-cesses of producing parts, microsystems or features at a scale of a few microm-eters and less than one hundred nanometers, respectively. Precise cutting and clean material removal accompanied with a negligible heat affected zone (HAZ), which are usually the characteristics of laser ablation, have
... Show MoreIn this research, nanofibers have been prepared by using an electrospinning method. Three types of polymer (PVA, VC, PMMA) have been used with different concentration. The applied voltage and the gap length were changed. It was observed that VC is the best polymer than the other types of polymers.
Background: The aim of this study was to evaluate the effect of thermo cycling and different pH of artificial saliva (neutral, acidic, basic) on impact and transverse strength of heat cure acrylic resin reinforced of with 5% silanated ZrO2 nano fillers. Materials and methods: 120 samples were prepared, 60 samples for impact strength test and another 60 samples for transverse strength test, for each test, samples were divided into two major groups (before and after thermo cycling), then each of these major groups were further subdivided into 3 subgroups according to the pH of prepared artificial saliva (neutral, acidic, basic). Charpy impact device was used for impact strength test and Flexural device was used for transverse strength test. R
... Show MoreThe paper discusses the structural and optical properties of In2O3 and In2O3-SnO2 gas sensor thin films were deposited on glass and silicon substrates and grown by irradiation of assistant microwave on seeded layer nucleated using spin coating technique. The X-ray diffraction revealed a polycrystalline nature of the cubic structure. Atomic Force Microscopy (AFM) used for morphology analysis that shown the grain size of the prepared thin film is less than 100 nm, surface roughness and root mean square for In2O3 where increased after loading SnO2, this addition is a challenge in gas sensing application. Sensitivity of In2O3 thin film against NO2 toxic gas is 35% at 300oC. Sensing properties were improved after adding Tin Oxide (SnO2) to be mo
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