Search

This study investigated the behavior of square footing (Length = 100 mm) constructed over a gypseous soil contaminated with four percentages of kerosene (5, 10, 15, and 20%) and several thicknesses of the contaminated soil (0.5B, B, and 1.5B) was taken from Tikrit University in Salah Al-Deen governorate from the depth of (1.5-2) m under natural ground level. The tests revealed that the soil is high gypsum content (62%). The main loading tests of the gypseous soil were carried out [field density (dry) and field density (with soaking)] which are a reference for comparison with the contaminated gypseous soil loading tests. The results that are represented by the relationship between pressure and settlement show that the gypseous soil has a good resistance reached to (385 kN/m2) when compacted to field density before soaking. For the contaminated gypseous soil tests, the bearing capacity does not improve as the bearing capacity is reduced by 50% or more compared to the non-contaminated gypseous soil, as for the settlement there is a slight improvement. As for the soaked gypseous soils, it was showing an improvement in bearing capacity and an improvement in the settlement of footing.

This work involves using the OFDM technique with the Time domain pilot-based channel estimation (TDPCE) to mitigate the effects of severe channel conditions such as fast and selective fading Raleigh channel with maximum Doppler shift equal to (120 Hz). The propose method has good robust performance, as compared to frequency domain channel estimation approaches. This method is based on comb pilot and Kalman filtering adaptive algorithm. Three digital modulation techniques including Quadrature Amplitude Modulation QAM 16, 32, and 64 were used in the OFDM transmitter with Rayleigh fading multipath channel. The OFDM performance was evaluated by measuring the bit error rate (BER) and the mean square deviation (MSD). Through simulation results, the (BER) has reached (0.0004, 0.004, and 0.01) when (Eb/No) is equal to (12 dB) using QAM 16, 32, and 64, respectively. Also, the convergence rate has almost reached (50, 50, and 125) iterations for the aforementioned QAM’s. These results can be taken into consideration as acceptable results in this paper compared to other results in the presence of severe conditions, where the value of maximum Doppler shift parameter of Rayleigh multipath fading channel is (120 Hz) or the user is available in a moving position.

The generation and accumulation of environmental pollutant of industrial contaminations gave it a big challenge to develop many removal strategies of pollution. Textile dyes as dispersive blue 26 dye affected by several decolorization parameters like as temperature, initial pH and initial concentrations of dye. These variables parameter were studied on ZnO-dye suspension solution in dark and photoreaction conditions. In dark reaction, with using thermodynamic and kinetic parameters such as ΔH°, ΔS°, ΔG° and Ea, the type of adsorption was determined and found as a physical adsorption, exothermic and fast reaction. Moreover, the results demonstrated that the photoreaction process under UV-light-A would elevated the rate of reaction, percentage of decolorization and accelerated the half-time of decolorization reaction in 50 ppm of dye. The photoreaction of decolorization of this dye acts as pseudo first order kinetics with endothermic, less random less, non spontenous and fast reaction.

The proliferation of the use of Photovoltaic PV systems, as one of the sources of electricity that comes from renewable energy resources, attracting the researchers to investigate on the factors that have an effect on the performance of it. This paper presents an analytical study for evaluating the performance of PV system that generates 2.5 kWp through the deployment of this system to supply the electricity for the Engineering Consultant office, of the College of Engineering at Wasit University, Iraq (32.497 N, 45.842 E). The evaluation is conducted by monitoring the pre-defined system which consists of 10 PV modules as an array of two rows. The system is supervised for six months from 1st of Feb. until 31st of July, to assess the impact of temperature, shading, and dust on its’ output power and performance. The PV array is omitted to 8˚ south-west, and 40˚ in elevation. The results shows that the PV array is operated at efficiency of 12.12% and the maximum efficiency reached 13.01 during April. The average daily power of it, for the months from Feb. until July are: 1.347 kW, 1.421kW, 1.436, 1.215 kw, 1.045kW and 1.042 kW, respectively. The minimum average output power is recorded in summer season (June and July), because of the high ambient temperature in these months. The maximum reduction of power due to shading at 4 pm is 52.77% in February followed by March 47.7 % and April 22.93 %, while the maximum reduction in efficiency due to shading were 51.82 %, 44.71%, 23.01% in February, March and April, respectively. The reduction in power due to the dust accumulated after 54 days exposure to environments conditions was 7.88%.

Energy conversion efficiency and power quality are both two key objectives of control schemes in wind energy conversation systems (WECS). These two tasks are hard to trade off and contradictory since improving the conversion-efficiency may boost fluctuation of output power as well. This paper suggests a hybrid control strategy for variable speed PMGS with Battery energy storage system to provide consistent power and meet variable load demands. In the suggested scheme, Fuzzy logic is combined with model predictive control (MPC) to capture the merits of these two different methods. The proposed controller (F_MPC) could improve wind turbine performance and provide power reliability. Simulation results prove that, in comparison with traditional PI model, the proposed topology can achieve benefits in terms of step response (overshoot), frequency deviation, and total harmonic distortion (THD) of almost 1.2%, 4.2%, and 1.24% respectively.

Physical properties of pure DESs and DESs mixed with different amounts of water were investigated by different techniques, including, rotational viscometer, Quartz Crystal Microbalance (QCM) and conductivity meter. In order to study heterogeneity of those liquids in nature. Analysis of these data showed some characteristics of heterogeneity, the extent of which depends on the number of hydrogen bond donors in the pure DES.

An economic and sensitive method was developed to measure pyridoxine hydrochloride (vitamin B6) in pharmaceutical formation as an ion pair, as depending on the charge transfer reaction with SDS as a surfactant and a suitable analytical reagent (chlorazol black). The parameters that gave optimum reaction conditions, such as the concentrations of chlorozal black, SDS, pH, equilibration temperature, time and effect of salting were studied to obtain a linear calibration curve where the linearity range was found to lie between 1.22 × 10-3to 34 × 10-2mM, and the detection limit (LOD) 2.56 × 10-4mM. The method was applied successfully to determine vitamin B6 concentrations in various pharmaceutical samples.