Aim of the research is the study of improving the performance of the thermal station south Baghdad and the main reasons for reduced its efficiency. South Baghdad power planet comprises (6) steam turbine units and (18) gas turbine units .The gas turbine units are composed of two groups: the first group is made up of gas units (1,2), each of capacity (123) MW. The design efficiency of gas turbine units is 32%. The actual efficiency data of steam units is 18.3% instead of 45% which is the design efficiency. The main reason for efficiency reduction of gas units is the rejected thermal energy with the exhaust gases to atmosphere, that are (450-510) ℃.The bad type of fuel used (heavy) fuel. Another reason for the low efficiency and has a negative impact on the steam and gas units. The actual efficiency that is calculated to set the first group gas unit (1) is (27%). Suppose the steam is passed through the (HRSG) and this (HRSG) passes the combustion products emerging from first group gas turbine unit (1). The temperature of exhaust gases (Tieg =783k) entered (HRSG) and the temperature of gas out from the (HRSG) (Toeg =374k). The thermal efficiency of combined -cycle plant is (the amount of fuel that can be available by using the plant compound in combined cycle, is (3603.88) tons per year. The relationship between the account of load and compression ratio during the three seasons of the year as where a large difference in the degree of heat between summer and winter .When the high temperature in summer less than the energy generated. As was the rate of energy produced is (99.8, 90.6, 70.6) MW in the (winter, autumn and summer), respectively.
The microstructure and wear properties of 392 Al alloy with different Mg contents were studied using centrifugal casting. All melted alloys were heated to 800 ºC and poured into the preheated centrifugal casting mold (200-250 ºC) at different mould rotational speeds (1500, 1900 and 2300 r.p.m). It is clear from the results obtained that wear rate was dependent on the Mg content, applied load and mould rotational speed. Furthermore, wear test showed that the minimum wear rate was found in the inner layer of produced rings at mould rotational speed of 1900 r.p.m and Mg content of 5%.
In this work, Pure and Cu: doped titanium dioxide nano-powder was prepared through a solid-state method. the dopant concentration [Cu/TiO2 in atomic percentage (wt%)] is derived from 0 to 7 wt.%. structural properties of the samples performed with XRD revealed all nanopowders are of titanium dioxide having polycrystalline nature. Physical and Morphological studies were conducted using a scanning electronic microscope SEM test instrument to confirm the grain size and texture. The other properties of samples were examined using an optical microscope, Lee's Disc, Shore D hardness instrument, Fourier-transform infrared spectroscopy (FTIR), and Energy-dispersive X-ray spectroscopy (EDX). Results showed that the thermal conductivity
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The thermal properties of four nematogenic Schiff’s bases, n-butyl-to-n-heptyl of bis (4-n-alkyloxybenzylidine)-2,3,5.6- tetramethyl-1, 4-phenylenediamine, have been studied. The transition temperatures and enthalpies of transition were examined by differential scanning calorimeter (DSC). Several correlations were carried out; those included the relations between transition temperatures, enthalpies and entropies of transition with increasing the
number of carbon atoms in the terminal alkyl chains. In addition, new regular relations were found between the ratio of the enthalpies and of the entropies, for noematic-isotropic transition and crystal-isotropic transition ( ΔΗÎ-i/AHC-I, ΔS
Abstract
The distribution is one of the elements of the marketing mix key by which companies can to deliver their products through private channels to all customers in right time and right place to check though in which the levels desired by customer satisfaction, the and purpose of the discussion dealt with the preparation of analytical studies to explain the impact of live performance of distribution channels in achieve customer satisfaction in industrial companies, as well as the diagnosis and the reality of the research variables in companies under study and describe the kind of relationship between changers Home on the one hand and the relationship between the variables sub on the other hand, represe
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تشكل سوق الاوراق المالية ركناً اساسياً من اركان هيكل النظام التمويلي في النظم الاقتصادية المعاصرة، لما تقوم به هذه الاسواق من دور مهم في حشد المدخرات المحلية وتوجيهها في قنوات استثمارية تعمل على دعم الاقتصاد القومي وتزيد من معدلات الرفاهية الاقتصادية لافراده، فضلاً عن كونها مرأة للوضع الاقتصادي العام في البلاد.
ونتيجة للروابط القوية بين سوق الاوراق المالية والاقتصاد، عُدّ استقرار ونمو
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Abstract
Digital repositories are considered one of the integrated collaborative educational environments that help every researcher interested in developing the education and educational process. The learning resources provided by the repositories are suitable for every researcher, so digital information can be stored and exchanged by ensuring the participation and cooperation of researchers, teachers, and those who are interested, as well as curricula experts, teachers, and students, to exchange each other’s experiences in constantly updating that information as a reason for developing their performance in education. This reveals the importance of the role of educational digital institutions by providing and
... Show MoreThe quality of groundwater is just as important as its quantity. The kinds and concentration of salts in groundwater depend on the environment, movement, and the source of the groundwater. During the field work, 20 samples have been collected from water wells from Al-Salman basin for two seasons represent wet and dry seasons in November 2017 and April 2018. After water well samples have been analyzed the Electrical conductivity values range from (2260 to 5500) μS/cm for dry season and range from (2540 to 5630) μS/cm for wet season, the Total dissolved solids values range from (1289 to 3582) ppm for dry season and range from (1710 to 3960) ppm for wet season, and pH values range from (7.11 to 7.3) for dry and wet seasons. The Hydroc
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Glucoamylase from black Aspergillus niger isolate was purified by ammonium sulfate precipitation and sephadex G 200 filtration. A trial for the purification of glucoamylase resulted in an enzyme with a specific activity of 6472 unit/mg protein with 10 times fold. The main goal of the present work was to test this enzyme in hydrolyzing the raw starch. Two substrates were used: corn starch and potato starch 2% (w/v). The effect of enzyme dosage and thermal processing of substrate on kinetics and efficiency of hydrolysis were studied. The results suggested that the glucoamylase activity is increased as the increase of enzyme concentration and the enzyme was sufficiently effective in hydrolyzing tested raw starch, and thermal modification of
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