The present study was carried out to assay the bioaccumulation of ammonia ,nitrite ,nitrate in fresh water and the concentration of heavy metals (Lead, Cupper, Cadmium, Manganes and Zinc) in water and tissues of Tilapia niloticus selected from El-marryotia canal (one of the river Nile ramification in Al-Giza city) in Egypt, samples were collected during the period of July to October 2011 to determine water safety for human consumption and the hazardous effect of these metals on the histopathology of selected tissues and organs of fish. Two samples were collected from two locations of canal, pH of water samples were measured and the concentration of ammonia, nitrate and nitrite were determined in these samples. Twenty Tilapia were also collected from different locations of the canal, One gram of liver, abdominal and dorsal muscles tissue from each fish were taken for determination of lead, Cupper, Cadmium, manganese and Zinc in the selected tissues. Specimens of gills, muscles, liver, kidney and intestine from each fish were fixed in 10% buffered neutral formalin, and processed for pathological study. The results revealed that water samples polluted with ammonia, nitrite and nitrate respectively.,significant differences were recorded in concentration of Mn and Zn in both water samples. The mean concentration of Pb was 0.216±0.0108, 0.204±0.009 and Mn 0.901±0.041, 0.73±0.003 in both water samples which was above the World Health Organization safety standard, the results indicated that water were polluted with both two heavy metals. More concentration of Pb1.362±0.0657 was noted in liver of fish , concentration of Pb (1.2±0.062), Cd (0.01.2±0.062) was the highest in abdominal muscles and lowest in the remaining tissues of fish , the mean concentration of Cu (0.6.2±0.032) was higher in abdominal muscle , Mn (0.54±0.02) and Zn (1,19.2±0.054) was more concentrated in dorsal muscles and all the heavy metals studied gave results with the permissible limits in fish tissue recorded by the standards of WHO. The main histopathological changes observed were edema and sloughing of lamellar epithelia in gills of fish. In liver, it was noticed vacuolation of most hepatocytes with nuclear pyknosis . The findings in kidneys exhibited the presence of periglomerular edema and vacuolar degeneration of most of renal tubules .The fish muscle showed degeneration and edema with focal areas of necrosis of some muscle fibres.
Trickle irrigation is a system for supplying filtered water and fertilizer directly into the soil and water and it is allowed to dissipate under low pressure in an exact predetermined pattern. An equation to estimate the wetted area of unsaturated soil with water uptake by roots is simulated numerically using the HYDRUS-2D/3D software. In this paper, two soil types, which were different in saturated hydraulic conductivity were used with two types of crops tomato and corn, different values of emitter discharge and initial volumetric soil moisture content were assumed. It was assumed that the water uptake by roots was presented as a continuous sink function and it was introduced into Richard's equation in the unsaturated z
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Fourier Transform-Infrared (FT-IR) spectroscopy was used to analyze gasoline engine oil (SAE 5W20) samples that were exposed to seven different oxidation times (0 h, 24 h, 48 h, 72 h, 96 h, 120 h, and 144 h) to determine the best wavenumbers and wavenumber ranges for the discrimination of the oxidation times. The thermal oxidation process generated oil samples with varying total base number (TBN) levels. Each wavenumber (400–3900 cm−1) and wavenumber ranges identified from the literature and this study were statistically analyzed to determine which wavenumbers and wavenumber ranges could discriminate among all oxidation times. Linear regression was used with the best wavenumbers and wavenumber ranges to predict oxidation time.
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Abstract:
The research sought to identify the crises that occurred during the research period and their reflection on the performance of the hotel Research sample as well as to identify the reality of auditing the hotel Research sample and the preparation of a performance audit program can be adopted in auditing the performance of hotels in light of crises, and the problem of the research lies in the lack of a program to audit the performance of hotels that takes into account the crises experienced by the hotel sector, The research was based on solving its problems on three hypotheses, the first is that the performance audit in light of the Covid-19 pand
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Magnetic abrasive finishing (MAF) process is one of non-traditional or advanced finishing methods which is suitable for different materials and produces high quality level of surface finish where it uses magnetic force as a machining pressure. A set of experimental tests was planned according to Taguchi orthogonal array (OA) L27 (36) with three levels and six input parameters. Experimental estimation and optimization of input parameters for MAF process for stainless steel type 316 plate work piece, six input parameters including amplitude of tooth pole, and number of cycle between teeth, current, cutting speed, working gap, and finishing time, were performed by design of experiment
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The objective of this work is to investigate the performance of a conventional three phase induction motor supplied by unbalanced voltages. An effort to study the motor steady state performance under this disturbance is introduced. Using per phase equivalent circuit analysis with the concept of symmetrical components approach, the steady state performance is theoretically calculated. Also, a model for the induction motor with the MATLAB/Simulink SPS tools has been implemented and steady state results were obtained. Both results are compared and show good correlation as well. The simulation model is introduced to support and enhance electrical engineers with a complete understanding for the steady state performance of a fully loaded induc
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This research aim to measure the critical success factors for total quality management applications, in order to know the key and important role played by these factors at applying the total quality management through a comparative study conducted in a number of a private colleges.
The research problem posed a set of questions, the most important ones are: Are the colleges (sample of research) aware of the critical success factors at applying the total quality management? What is the availability of the critical success factors at the work of the colleges (sample of research)?
What are the critical success factors in the work of the researc
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The Fort Munro Formation is well exposed along DG Khan-Fort Munro road, a type locality. The section was measured and sampled for the biostratigraphy, where it has a conformable lower contact with Mughalkot Formation and is underlain by the Pab Sandstone. The total observed thickness was 105 meters, and 26 samples were collected from top to the bottom at random intervals. Fifty thin sections were studied carefully, and five species of large benthic foraminifera, including Orbitoidestissoti, Orbitoidesapiculata, Orbitoides media, Orbitoideshottingeri, and Omphalocyclusmacroporus were identified along with miliolids. Gastropods, Bivalves and Echinoderms were also observed. Based on identified microfossils, the de
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Arabic calligraphy is one of the greatest achievements of Islamic art. The visual form of Arabic calligraphy is the primary means of presenting ideas and messages for expressive communication in Arabic typefaces. Emerging computer technology with calligraphy is essential for effective visual designs; however, traditional typefaces are insufficient in number and quality to fulfill the requirements of the current Saudi industry. Thus, this research investigates the processes followed by graphic designers to create modern Arabic type designs inspired by Arabic calligraphy, and presents the characteristics of Arabic calligraphy. The research implemented a mixed experimental and descriptive method, exploring 10 typefaces designed by professio
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The A2?u-X1?g+ emission band system of 7LiH1 molecule has been calculated for Lambda doubling. The relation between wave number ?p , ?Q , ?R conducted the energies of the state of rotation F (J), and (J + 1) with rotational quantum number J, respectively, of 7LiH1 molecule for statehood A2?u using the rotation, fixed vibrational states of both the ground and raised crossovers vibrational against ???= 0 to V ' = 0-4using rotational levels J = 0 to J = 20 have found.