Carbon nanoparticles are prepared by sonication using carbon black powder. The surface morphology of carbon black (CB) and carbon nanoparticles (CNPs) is investigated using scanning electron microscopy (SEM). The particles size ranges from 100 nm to 400 nm for CB and from 10 nm to 100 nm for CNPs. CNPs and CB are mixed with silicon glue of different ratios of 0.025, 0.2, 0.05, and 0.1 to synthesis films. The optical properties of the prepared films are investigated through reflectance and absorbance analyses. The ratio of 0.05 for CNPs and CB is the best for solar paint because of its higher solar water heater efficiency and is then added to the silicon glue . Temperature of cold water and temperature of hot water in storage tank were tabulated on hourly basis with the help of an Arduino device. The atmospheric temperature was also noted. It was observed that outlet temperature of water was attained up to 75°C as compared to the inlet water temperature of 23°C for the tank applied with CNP-based paint. The tank applied with CNP-based paint has 4 °C higher water temperature than that coated with CB-based paint after 1 month of test under sun irradiation. Based on the results, the efficiency of a solar water heater depends on the difference in temperature of inlet water and outlet of heater. The efficiency of the solar water heater coated with CNPs is around 77% but the solar water heater coated with CB has an efficiency of 67%.
When optimizing the performance of neural network-based chatbots, determining the optimizer is one of the most important aspects. Optimizers primarily control the adjustment of model parameters such as weight and bias to minimize a loss function during training. Adaptive optimizers such as ADAM have become a standard choice and are widely used for their invariant parameter updates' magnitudes concerning gradient scale variations, but often pose generalization problems. Alternatively, Stochastic Gradient Descent (SGD) with Momentum and the extension of ADAM, the ADAMW, offers several advantages. This study aims to compare and examine the effects of these optimizers on the chatbot CST dataset. The effectiveness of each optimizer is evaluat
... Show MoreInvestigating the thermal and electrical gains and efficiencies influence the designed photovoltaic thermal hybrid collector (PVT) under different weather conditions. The designed system was manufactured by attaching a fabricated cooling system made of serpentine tubes to a single PV panel and connecting it to an automatic controlling system for measuring, monitoring, and simultaneously collecting the required data. A removable glass cover had been used to study the effects of glazed and unglazed PVT panel situations. The research was conducted in February (winter) and July (summer), and March for daily solar radiation effects on efficiencies. The results indicated that electrical and thermal gains increased by the incre
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This research aims to understand complexity management and its impact on the use of the dynamic capabilities of a sample of private colleges. Private colleges are currently facing many crises, changes, unrest and high competitive pressures. Which is sometimes difficult or even impossible to predict. The recruitment of dynamic capabilities is also one of the challenges facing senior management at private colleges to help them survive and survive. Thus, the problem of research was (there is a clear insufficiency of interest in Complexity Management and trying to employ it in improving the dynamic capabilities of Colleges that have been discussed?). A group of private colleges was selected as a
... Show MoreAn ultrasonic treatment was applied to the vacuum gas oil at intervals of 5 to 30 minutes, at 70°C. In this work, the improvement of the important properties of Iraqi vacuum gas oil, such as carbon residue, was studied with several parameter conditions that affect vacuum efficiency, such as sonication time (5, 10, 15, 20, 25, and 30) min, power amplitude (10–50%). After ultrasonic treatment, the carbon residue of vacuum gas oil was evaluated using a Conradson carbon residue meter (ASTM D189). The experiment revealed that the oil's carbon residue had decreased by 16%. As a consequence of the experiment It was discovered that ultrasonic treatment might reduce the carbon residual and density of oil samples being studied. It also notice
... Show MoreIn this paper synthesis and extensive investigation of the microstructural and optoelectronic properties of polyaniline (PANI), Multiwalled carbon nanotube (MWCNTs) and MWCNTs reinforced PANI composites is presented. MWCNTs- PANI composites have been deposited by spin coating on silicon wafer substrate. Fourier Transform Infrared Spectroscopy shows no difference between PANI and its composites. However a change in peaks shape and absorption intensity has been observed. A strong effect of the MWCNTs weight percentage on the PANI/MWCNTs composites has been demonstrated. It was find that the thermal stability improved with increasing MWCNTs content. The optical band gap of the PANI thin
The performance of photovoltaic (PV) panel having staggered metal foam fins was examined experimentally in Baghdad, Iraq. Three staggered metal foam fin configurations attached to the backside of the PV panel were studied. The measured parameters were front and back surfaces temperature, open voltage and current circuits, maximum power, and PV efficiency. It was noted that the maximum electrical efficiency enhancement was 4.7% for staggered metal foam fins (case III) than the reference PV panel. The operating temperature of the cell was increased when the value of solar intensity was high. Thereby, the electrical efficiency was decreased. It was found that the metal foam fins decreased the PV temperature by 2-3 o
... Show MoreIn Iraq most of the small buildings deployed a conventional air conditioning technology which typically uses electrically driven compressor systems which exhibits several clear disadvantages such as high energy consumption, high electricity at peak loads. In this work a thermal performance of air conditioning system combined with a solar collector is investigated theoretically. The hybrid air conditioner consists of a semi hermetic compressor, water cooled shell and tube condenser, thermal expansion valve and coil with tank evaporator. The theoretical analysis included a simulation for the solar assisted air-conditioning system using EES software to analyze the effect of different parameters on the power consumption of c
... Show MoreThis study was carried out at University of Baghdad - College of Agricultural Engineering Sciences - research station B during the fall season of 2019-2020, in order to evaluate the effect of Ozone enrichment and the foliar application of organic nutrient on nutrient and water use efficiency and fertilizer productivity of broccoli plant using the modified NFT film technology. A factorial experiment (2*5) was carried out within Nested Design with three replicates. The ozone treatment was distributed into the main plots which consisted of oxygen (O2) and ozone (O3). The foliar application of organic nutrients were distributed randomly within each replicate including five treatments, which were the control treatment (T0), Coconut wat
... Show MoreThe present paper is an experimental study to improve the productivity of the conventional solar still. This done by modifying conventional still in a way that the distilled basin is larger than distillation basin, thus providing an increase in the condensation surface and speeding up the condensation process. Moreover, increase in the dimensions of the distilled base helps coupling reflective panels to the distilled base to reflect incident solar radiation to the distillation basin. For this purpose , two solar stills were made, one conventional designand another made according to the proposed design. The two solar stills were tested during the period from February to July 2009 under varying weather conditions of Basra, Iraq (latitude o
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The aim of the research is to measure the effect of changing the exchange rate on bank loans, and in order to achieve this goal, the (official exchange rate) was chosen as an independent variable and its effect was studied on the dependent variable, which is bank credit. Commercial Gulf, Baghdad, A Shore International for Investment (and the financial indicators (growth rate of loans) and the statistical program (Eviews 12) were used to measure the impact of the exchange rate change on the bank credit of banks, the research sample for the period 2012-2022, and the research reached a group Among the conclusions, the most important of which is that the
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