The present work aims to fabricate n-i-p forward perovskite solar cell (PSC) withئ structure (FTO/ compact TiO2/ compact TiO2/ MAPbI3 Perovskite/ hole transport layer/ Au). P3HT, CuI and Spiro-OMeTAD were used as hole transport layers. A nano film of 25 nm gold layer was deposited once between the electron transport layer and the perovskite layer, then between the hole transport layer and the perovskite layer. The performance of the forward-perovskite solar cell was studied. Also, the role of each electron transport layer and the hole transport layer in the perovskite solar cell was presented. The structural, morphological and electrical properties were studied with X-ray diffractometer, field emission scanning electron microscope and current-voltage (J-V) characteristic curves, respectively. J-V curves revealed that the deposition of the Au layer between the electron transport layer (ETL) and Perovskite layer (PSK) reduced the power conversion efficiency (PCE) from 3% to 0.08% when one layer of C. TiO2 is deposited in the PSC and to 0.11% with two layers of C. TiO2. Power conversion efficiency, with CuI as the hole transport layer (HTL), showed an increase from 0.5% to 2.7% when Au layer was deposited between PSK and CuI layers. Also, Isc increased from 6.8 mA to 17.4 mA and Voc from 0.3 V to 0.5V. With depositing Au layer between P3HT and PSK layers, the results showed an increase in the efficiency from 1% to 2.6% and an increase in Isc from 10.7 mA to 30.5 mA, while Voc decreased from 0.75 V to 0.5V
The research aims to measure the impact of the quality of the audit on the Earnings Quality, for a sample of private joint stock companies listed on the Iraq Stock Exchange, as the research sample included (14) private and listed joint stock companies in issuing their financial statements for the period from (2010-2018), as well as companies The audit offices in charge of auditing these companies, which number (18) companies or an audit office, and the research relied on two main models for measurement, as the first model reflects the assumed relationship between independent variables represented in the characteristics of external audit quality and measuring the extent of its impact on the dependent variable represented in the Ea
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In this work, diabetic glucose concentration level control under disturbing meal has been controlled using two set of advanced controllers. The first set is sliding mode controllers (classical and integral) and the second set is represented by optimal LQR controllers (classical and Min-, ax). Due to their characteristic features of disturbance rejection, both integral sliding mode controller and LQR Minmax controller are dedicated here for comparison. The Bergman minimal mathematical model was used to represent the dynamic behavior of a diabetic patient’s blood glucose concentration to the insulin injection. Simulations based on Matlab/Simulink, were performed to verify the performance of each controll
... Show MoreIn this research an experimental study has done for testing the thermal performance of selective surfaces used in solar collectors for substrate of iron, galvanized iron and aluminum which are commercially available. The coating process for the samples has done in two ways, the electroplating and the chemical spray pyrolysis. The results of the thermal performance test of these samples are comparing with the thermal performance of a sample without paint and other paint with black paint without shines commercially available. For the electroplated samples, the performance study has done for different immersion time in plating bath, the
distance between electrical poles, the current density, and area ratio of the sample plated area to
This article deals with the impact of including transverse ribs within the absorber tube of the concentrated linear Fresnel collector (CLFRC) system with a secondary compound parabolic collector (CPC) on thermal and flow performance coefficients. The enhancement rates of heat transfer due to varying governing parameters were compared and analyzed parametrically at Reynolds numbers in the range 5,000–13,000, employing water as the heat transfer fluid. Simulations were performed to solve the governing equations using the finite volume method (FVM) under various boundary conditions. For all Reynolds numbers, the average Nusselt number in the circular tube in the CLFRC system with ribs was found to be larger than that of the plain abs
... Show MoreIn solar-thermal adsorption/desorption processes, it is not always possible to preserve equal operating times for the adsorption/desorption modes due to the fluctuating supply nature of the source which largely affects the system’s operating conditions. This paper seeks to examine the impact of adopting unequal adsorption/desorption times on the entire cooling performance of solar adsorption systems. A cooling system with silica gel–water as adsorbent-adsorbate pair has been built and tested under the climatic condition of Iraq. A mathematical model has been established to predict the system performance, and the results are successfully validated via the experimental findings. The results show that, the system can be operational
... Show Moreobjective the research to diagnosis and interpretation of the nature of the effect between the basic elements of knowledge management (tecgnology , structure , culture , process , human resource ) and the strategic performance of the Iraqi private banks, the research community and the level dimensions, and I've tested this research in the private banking sector represented by (7), especially in Baghdad, Iraqi banks, and applied research on sample consisting of 100 distributors in several administrative levels Director (Director, Director of the department, branch manager), and use the researcher questionnaire Head to collect data and information tool, and some private banks annual reports, has sought research to test
... Show MoreIncreasing the variety of products that are being designed with sculptured surfaces, efficient machining of these surfaces has become more important in many manufacturing industries. The objective of the present work is the investigation of milling parameters for the sculptured surfacesthat effecting of surface roughness during machining of Al-alloy. The machining operation implemented on C-TEK CNC milling machine. The influence of the selected variables on the chosen characteristics have been accomplished using Taguchi design approach, also ANOVA had been utilized to evaluate the contributionsof each parameter on proc
... Show MoreEmpirical research in the disciplines of art and design has started to escalate and gather consideration within the academic community over the past few decades. However, still, graphic design tends to be a topic extremely under-researched by scholarly persons. Profound research in the field of graphic design extends far beyond the works produced by the designer himself (Khoury, 2009, p.844). In order to develop a clear insight, one needs to delve deep into the subcategories that the diverse field of graphic design is comprised of, including illustration, typography, interaction design, branding and even the impact of notable, eminent institutes from around the world that have taken the budding artists for quite a long time (Walke
... Show MoreA thin CdS Films have been evaporated by thermal evaporation technique with different thicknesses (500, 1000, 1500 and 2000Å) and different duration times of annealing (60, 120 180 minutes) under 573 K annealing temperature, the vacuum was about 8 × 10-5 mbar and substrate temperature was 423 K. The structural properties of the films have been studied by X- ray diffraction technique (XRD). The crystal growth became stronger and more oriented as the film thickness (T) and duration time of annealing ( Ta) increases.
The Cu2SiO3 composite has been prepared from the binary compounds (Cu2O, and SiO2) with high purity by solid state reaction. The Cu2SiO3 thin films were deposited at room temperature on glass and Si substrates with thickness 400 nm by pulsed laser deposition method. X-ray analysis showed that the powder of Cu2SiO3 has a polycrystalline structure with monoclinic phase and preferred orientation along (111) direction at 2θ around 38.670o which related to CuO phase. While as deposited and annealed Cu2SiO3 films have amorphous structure. The morphological study revealed that the grains have granular and elliptical shape, with average diameter of 163.63 nm. The electrical properties which represent Hall effect were investigated. Hall coeffici
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