The effects of fly ash class F To get high strength Concrete

Based on the results of research and discussion that has been described, it can be concluded into which are as follows : Age care greatly affect the strength of concrete, At the age of 28 days the compressive strength of concrete obtained at normal (without the use offlyash), Experiencing an increase, compressive strength of normal concrete compressive strength is obtained to exceed the plan that is equal to 28.875MPa. At the levels of fly ash 20% obtained higher scores than normal concrete in the amount of 47.369MPa, whereas the levels of fly ash 5%, 10%, and 15% also increased the compressive strength of 37.178MPa36.423MPaand32.838MPa respectively, at levels of fly ash 15% at 28 days compared with normal concrete (without the use of fly ash) the difference is too small, the importance of the optimal levels at 28 days was 5% - 20% of the weight of the cement and the high strength, so we conclude from this mix design that we should be careful when start mix all the component and follow the numbers that we got in the mix design

Operation cost reduction in unit commitment problem using improved quantum binary PSO algorithm

Unit Commitment (UC) is a nonlinear mixed integer-programming problem. UC is used to minimize the operational cost of the generation units in a power system by scheduling some of generators in ON state and the other generators in OFF state according to the total power outputs of generation units, load demand and the constraints of power system. This paper proposes an Improved Quantum Binary Particle Swarm Optimization (IQBPSO) algorithm. The tests have been made on a 10-units simulation system and the results show the improvement in an operation cost reduction after using the proposed algorithm compared with the ordinary Quantum Binary Particle Swarm Optimization (QBPSO) algorithm

Seroprevalence of cytomegalovirus and rubella among pregnant women in western Sudan

<p>Abstract</p> <p>Background</p> <p>Maternal cytomegalovirus (CMV) and rubella infections have adverse neonatal outcomes. Basic epidemiological data concerning CMV and rubella is necessary for health planners and care providers.</p> <p>Methods</p> <p>A cross sectional study was conducted at El-Rahad hospital, Sudan to investigate seroprevalence of CMV and rubella infections and associated possible risk factors among pregnant women. Structured questionnaires were used to gather socio-demographic data and ELISA was used to detect CMV and rubella infections using IgG and IgM.</p> <p>Results</p> <p>Out of 231 pregnant women, 167 (72.2%) and 151 (65.3%) were CMV-IgG and rubella-IgG positive, respectively. Only 6 (2.5%) and 8 women (3.4%) were CMV-IgM and rubella-IgM positive, respectively. While, high parity (OR = 14.7, 95%CI = 1.7 - 123.6; <it>P </it>= 0.01] and illiteracy (OR = 3.0, CI = 1.4 - 6.5; <it>P </it>= 0.004) were significantly associated with seropostive CMV-IgG in multivariate analysis, none of the other obstetrical and medical characteristics were significantly associated with CMV or rubella infections.</p> <p>Conclusion</p> <p>CMV prevalence was 72.2% and rubella susceptibility among pregnant women was 34.6%. Rubella vaccine and routine screening for rubella and CMV should be introduced for pregnant women in this setting. Further research is needed.</p

Calculation the thermodynamic parameters required for stability of roton

This work aims to search about the thermodynamic properties of phonons and rotons in Hellium II (thermodynamic potential, roton energy, particles number). It is noticed from the curves the energy gap depth in roton cell has a value of Correspond to wave number . In addition, the curve of the ratio between normal component density ρn to the total density of liquid helium ρ as a function of temperature. The diagram illustrated the difference between  in the range (0.9 – 1.8)K.

A single stage full bridge power factor corrected AC/DC converter

Conventional single phase AC/DC converters use a two stage power configuration to provide a regulated DC power supply at high input power factor. Elimination of one of these stages can reduce the cost, weight, size, complexity and increase the overall reliability of this converter. This thesis proposes a single stage power factor correction converter circuit. This proposed converter circuit uses the traditional non-power-factor corrected circuit configuration with only few additional components. These are: an additional winding on the high frequency transformer, a small high frequency inductor and three diodes. The topology allows the output voltage regulation and input current shaping with a single power processing stage and one control chip. In addition, it is shown that this converter can be designed to offer soft switching of the full bridge switches. The operating principles of the proposed converter are discussed and its performance characteristics under steady state conditions are examined. A design procedure is illustrated to select the components of the converter for a 500 W power supply operating at 50 kHz. Theoretical results are verified with simulation and experimental tests on a 500 W laboratory prototype

Simulation of Ammonia Production using HYSYS Software

Now-a-days, Because of cost and time consuming in the design of plants chemical engineer used simulators to simulate design and operation of chemical equipment and plant,  which spares a great deal of time and cash.Today, there are many number of the simulators are refreshed and utilized in the simulation of chemical equipment and plant such as ChemCad, ProII, UniSim……..etc. Among of these simulators, Aspen Hysys is the most utilized programming in all ventures because of aiding in two noteworthy fields (design &amp; operation). Simulation of ammonia synthesis process is done on Aspen Hysys V8.8 with steady state mode making some assumptions and using hypothetical reactors ammonia. By fluctuating the distinctive parameters in this simulation environment, the impact of these parameters in the generation rate of the procedure are watched. Keywords: Ammonia, Simulation, Aspen Hysys DOI: 10.7176/CPER/62-03 Publication date: January 31st 202