The current study suggested a thermal treatment as a necessary proactive step in improving the adsorption capacity of bio-waste for contaminants removal in wastewater. This approach was based on the experimental and histological investigation of biowaste pods shell. This investigation showed that these shells compose of parenchyma cells that store secondary metabolites compounds produced from cells were exhibited in present study. The results also reported that these compounds are extracted directly from the cells as soon as they are exposed to an aqueous solution, hampering their use as an adsorbent material. The increase in the weight of bio-waste adsorbent at unit liquid volume increases the production of secondary metabolites compounds under normal conditions. While thermal conditions accelerate the exit of these compounds from their storage places. After suggested thermal processing, the bio-waste was examined for azo dye removal under different operational conditions (adsorbent weight (1,0.1 g), contact time (24 and 48 hr), and temperature (30, 40, 50,and 60°C). In general, the experimental data showed a good improvement in adsorption potential. The results presented clearly that the increase in temperature has a positive effect on the performance of pollutant removal. The maximum adsorption capacity was 0.035833 mol/g at a temperature of 40°C, and 0.036417 mol/g at a temperature of 50°C. This behaviour may be counterproductive with high temperatures as a result of the release of more secondary metabolites compounds. For other operating conditions, increasing the concentration of the pollutant also improves the efficiency of the process, while this efficiency decreases with the increasing weight of the adsorbent material. For example, the removal capacity was (0.000275, 0.00675 mol/g) with 1 and 0.1 g of the adsorbent weight, respectively. Finally, the present study concluded that the adoption of thermal pre-treatment technology for bio-mass waste is a necessary step in improving the adsorption processes.
A new approach for baud time (or baud rate) estimation of a random binary signal is presented. This approach utilizes the spectrum of the signal after nonlinear processing in a way that the estimation error can be reduced by simply increasing the number of the processed samples instead of increasing the sampling rate. The spectrum of the new signal is shown to give an accurate estimate about the baud time when there is no apriory information or any restricting preassumptions. The performance of the estimator for random binary square waves perturbed by white Gaussian noise and ISI is evaluated and compared with that of the conventional estimator of the zero crossing detector.
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Phoenix dactylifera l. pinnae (the green leaves of dates palm) were used as natural reinforcing (strengthening) fibers to improve the mechanical properties of polyester as a matrix material, the fibers of the green leaves of dates palm were used in two lengths, 10 and 20mm with five rates of 0, 2.5, 5, 10, and 20% , where the reinforcing with the leaves fibers increases the hardness strength from 76.5 to be about 86.55 , the Impact value raised from about 0.313 to 0.461 , in addition to that the flexural strength from 2.66 to be about 55 , and the thermal conductivity increases from 2.54 𝑤∕𝑚.℃ to 5.41 𝑤∕𝑚.℃. The results of the present search explains that the composite samples reinforced at rate 20% and 10mm fiber length
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In this paper, an experimental study of the thermal performance for hybrid solar air conditioning system was carried out, to investigate system suitability for the hot climate in Iraq. The system consists of vapor compression unit combined with evacuated tube solar collector and liquid storage tank. A three-way valve was installed after the compressor to control the direction flow of the refrigerant, either to the storage tank or directly to the condenser. The performance parameters were collected by data logger to display and record in the computer by using LabVIEW software. The results show that the average coefficient of performance of hybrid solar air conditioning system (R=1) was about 2.42 to 2.77 and the average p
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