Thin films of pure polycarbonate (PC) with anthracene doping PC films for different doping ratios (10, 20, 30, 40, 50 and 60 ml) were prepared by using a casting method. The influence of anthracene doping ratio on photo-fries rearrangement of polycarbonate was systematic investigated. Furthermore, pure PC and anthracene doping PC films were irradiated via UV light at a wavelength (254 nm) for different periods (5, 240, 288, and 360 hrs). The photo-fries rearrangement occurring in pure PC and anthracene doping PC films were monitored using UV and FTIR spectroscopies. The photo-fries rearrangement leads to scission the carbonate linkage and formation phenylsalicylate and dihydroxybenzophenes. The result of the UV spectrum confirms disappear of polycarbonate peaks, while phenylsalicylate and dihydroxybenzophenone peaks appear at (320 nm) and (360 nm), respectively. The formation of a dihydroxybiphenyl compound reveals when the UV peak distinguishes at (340 nm). FTIR spectroscopy supported forms of phenylsalicylate and dihydroxybenzophenone compounds which appear in carbonyl region at (1689 cm-1) and (1630 cm-1), respectively. It founds that anthracene accelerates the photo-fries rearrangement of polycarbonate in the anthracene doping PC films because anthracene leads to formation of excited singlet state oxygen (1O2). Singlet oxygen (1O2) leads to the formation of a hydro peroxide, which could decompose and cause to chain scission and formation of a terminal of a carbonyl group. The presence of the carbonyl groups in the polymer makes it photo-labile, also warns that the polymer is vulnerable to deterioration.
In this research we studied the structural and optical properties of (CdTe) thin films which have been prepared by thermal evaporation deposition method on the glass substrate at R.T with thickness (450  25) nm., as a function of doping ratio with copper element in (1,3,5) % rate .The structure measurement by X-ray diffraction (XRD) analyses shows that the single phase of (CdTe) with polycrystalline structure with a preferred orientation [111]. The optical measurement shows that the (CdTe) films have a direct energy gap, and they decrease with the increase of doping ratio reaching to 5% . The optical constants are investigated and calculated, such as absorpti
... Show MoreThe electrospun nanofibers membranes (ENMs) have gained great attention due to their superior performance. However, the low mechanical strength of ENMs, such as the rigidity and low strength, limits their applications in many aspects which need adequate strength, such as water filtration. This work investigates the impact of electrospinning parameters on the properties of ENMs fabricated from polyacrylonitrile (PAN) solved in N, N-Dimethylformamide (DMF). The studied electrospinning parameters were polymer concentration, solution flow rate, collector rotating speed, and the distance between the needle and collector. The fabricated ENMs were characterized using scanning electron microscopy (SEM) to understand the surface morphology and es
... Show MoreThe photonconductor detectors CdSe:Cu was fabricated as a thin film of (1 μm) in thickness using vacuum evaporation technique. doping with copper was made using vacuum annealing at 350oC under argon atmosphere . The spectral responsivity and spectral detectivity of the detector were determined as a function of incident wavelength on the sample. A remarkable improvement in performance was absorbed for the specimen, which doping with (1-5 wt%) Cu.
The spectral response increases with increasing of wavelength for incident radiation to maximum value, after that , it reduced sharply . There is a shifting for peak responsivity indirect of higher wavelength. The detectivity was increased with doping but its decreased as the concentration in
Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated z
... Show MoreAcinetobacter baumannii received attention for its multi-drug resistant associated with many severe infections and outbreaks in clinical environment. The aims of the study are to investigate the antibiotic susceptibility profile of clinically isolated A. baumannii, biofilm production, and the efficiency of Low Frequency Ultrasound (LFU) and honey to attenuate biofilm production. A total of 100 samples were taken from different sources from Baghdad hospitals. The susceptibility patterns revealed the percentage of pan drug resistant (PDR) isolates were 1.5 %, 72.7 % were extended drug resistant (XDR), 16.7 % were multidrug resistant (MDR), and 9.1 % were non MDR and sensitive to most antibiotics used. The ability to form
... Show MoreThe aim of this work is to study the effect of diesel fuel percentage on the combustion processes in compression ignition engine using dual – fuel (diesel and LPG).
The brake thermal efficiency increased with the increase of diesel fuel rate at low loads, and decreased when load increased. To get sufficient operation in engine fueled with dual fuel, it required sufficient flow rate of diesel fuel, if the engine fueled with insufficient diesel fuel erratic operation with miss fire cycles presented.
Dual-fuel operation at part load showed higher specific fuel consumption than straight diesl operation. At full loads, brake specific fuel consumption of duel fuel engine approaches that for diesel fuel values.
Reverse Phase High Performance Liquid Chromatography (RP-HPLC) was coupled with ultraviolet absorption sepectoscopy (UV) for separation and identification of Naphthalene, Acenaphthylene, Pyrene, Benz{a} anthracene and 1,3,2,4-Dibenzanthracene. RP-HPLC was performed on an ODS-C18 column (150×4.6 mm I.D) using acetonitrile–buffer phosphate as mobile phase. UV absorption spectra of the elutes was detected in 254 nm, and studying the chromatographic variables include organic modifier ratio, PH, column temperature and concentration of buffer to maximize resolution and minimize separation time. the results showed that using mobile phase( 80:20) v/v acetonitrile:0.01M phosphate buffer solution at PH 6 with flow rate 1ml/min and column te
... Show MoreThe research dealt with the risks of reinsurance and its impact on the financial performance of the National Insurance Company by focusing on reinsurance in the marine insurance branch. Negative impact on the financial performance of the NICs and the Marine Insurance Branch. The research sample resulted in a main hypothesis that reflects this relationship. Lee in the analysis of financial information reports National Insurance Company of the branch of marine insurance for the period of 2010 until 2017, and the use of (retention) for measuring the re-insurance operations index, and (insurance financial surplus rate) to measure financial performance. For the purpose of obtaining the results, a number of statistical methods were used accord
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The results showed that the organic fertilizer mixture (1:1) 30 tons/ha with chemical fertilization recorded the lowest level of bulk density of 1.2 g/cm3, the organic fertilizer mixture (1:1) 30 tons/ha with chemical fertilization recorded the highest percentage of aggregation stability amounting to 16.17%, the organic fertilizer palm fronds recorded the highest level of ready water with an average of 5.50 cm3/cm3 and the organic fertilizer mixture (1:1) 30 tons/ha without chemical fertilization recorded the highest level of ready water as it reached 6.93%, the or
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