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This work includes design, manufacture and improvement of a Waste Heat Recovery System (WHRS) for thermal energy storage unit by using PCM technique. Paraffin wax produced by Al- Durra refinery (major Iraqi oil company) has been used as a phase change material for this purpose. The heat transfer enhancement has been investigated experimentally and numerically by using perforated and smooth copper strips which inserted within paraffin wax in the form of fins. These coppers fins were welded with copper pipes in which water is flow inside it during the discharge process. The effect of fins and perforated fins with three different size of diameters (2,3 and 4 mm), on the heat transfer of PCM during melting process has been investigated to selecting the optimum among them. The results obtained indicate that inserting copper strips mainly rises heat transfer by conduction inside PCM and decreases the time of melting by about, 16% due to high thermal conductivity of this strips and the smooth fins are more useful than perforated fins for improving the thermal properties of paraffin wax and the rate of heat transfer. It is also found that the increase in the diameter of the perforations led to decrease the thermal performance of the fins.

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In this work, we have considered the effect of the various properties on the thermal field, the absorptivity plays a special role, because it controls directly the heat input to the sample, while being itself a function of surface temperature. In order to take this dependence into account, the one-dimensional heat conduction equation was solved for a semi-infinite geometry using variable absorptivity and assuming constant thermal conductivity and thermal diffusivity. It is shown that the surface temperature satisfies an Abel integral equation with an approximate analytical solution that gives a temperature rise at the surface linear with t. Comparison is made between analytical approximate expressions, numerical solutions, previous models and experimental results.

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A numerical investigation is adopted for a two dimensional thermal energy storage system (TES), employing finite element method to compute the time of charging or discharging energy from a phase change material (PCM) during day or night to utilize it in free cooling of space applying Baghdad Summer climate conditions (ambient temperature). A computer program is developed to analyze the thermal energy unit for different tube diameters, air flow rates and inlet air temperature for both solidification and melting processes. This study shows that utilizing small tube diameter, low flow rates or air inlet temperature near the fusion temperature lead to increase time of phase change process. It was also shown that the time duration of melting is larger than solidification.

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An analytical method and a two-dimensional finite element model for treating the problem of laser heating and melting has been applied to aluminum 2519T87and stainless steel 304. The time needed to melt and vaporize and the effects of laser power density on the melt depth for two metals are also obtained. In addition, the depth profile and time evolution of the temperature before melting and after melting are given, in which a discontinuity in the temperature gradient is obviously observed due to the latent heat of fusion and the increment in thermal conductivity in solid phase. The analytical results that induced by laser irradiation is in good agreement with numerical results.

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The present study was carried out to detect the genotype of E. histolytica that found in human fecal specimens and animals feces with Haemorrgic diarrhea by amplifying the SREHP gene, using RT-PCR technique, Cyber green dye and by fusion curve analysis. The study also included molecular detection of amoebic parasite species using Nested-PCR technology. The study recorded presence of parasites E. histolytica; E. dispar; E. bovis with total infection rates 82.9, 26.8, 4.9%, respectively. The study revealed the presence of E. histolytica parasite in five different genotypes (I, II, III, IV, V) with rate presence 9.75, 53.65, 19.5, 9.75, 7.3%, respectively. In conclusion, there are five genotype of E. histolytica, in human and animals, most of these genotypes may be infect any host, E. bovis was recorded in sheep and cows.

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The present study explores numerically the energy storage and energy regeneration during Melting and Solidification processes in Phase Change Materials (PCM) used in Latent Heat Thermal Energy Storage (LHTES) systems. Transient two-dimensional (2-D) conduction heat transfer equations with phase change have been solved utilizing the Explicit Finite Difference Method (FDM) and Grid Generation technique. A Fortran computer program was built to solve the problem. The study included four different Paraffin's. The effects of container geometrical shape, which included cylindrical and square sections of the same volume and heat transfer area, the container volume or mass of PCM, variation of mass flow rate of heat transfer fluid (HTF), and temperatures difference between PCM and HTF were all investigated. Results showed that the PCMs in a cylindrical container melt and solidify quicker than the square container. The increase in mass flow rate and/or temperature difference decreases the time required for complete phase change. Paraffin's solidify quicker than they melt and store more energy than they release.

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Ni23Cr6Al0.4Y plasma sprayed coating on nimonic75 substrate was remelted using a 1kW continues CO2 laser. The topography, microstructure, phases and chemical analysisof plasma sprayed and laser melted regions were examined using various techniquesincluding scanning electron microscope (SEM), electron probe microanalysis (EPMA),energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The plasmasprayed coatings consisted heterogeneous microstructure of lamella with unmeltedparticles, voids, porosity and cracks. It was found that the depth of melting increasedwith increasing the specific energy. Homogenous and shiny melted regions wereachieved without voids, porosity and cracks after laser melting. Thin upper surfacelayers with shallow cracks were observed due to the rich layer of α-Al2O3 and YAlO3.No phases changed were found before and after laser melting of plasma sprayed layers.The phases formed are mixtures of γ’, β, YAlO3 in the matrix γ. The microstructureformed after laser melting is fine cells.Keywords: Plasma sprayed coating; Laser melting, Ni solid solution; YAlO3; α-Al2O3

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The study included extracting of gelatin from the fish`s skin Cynoglossus bilineatus using acid and alkaline pretreatment the chemical analysis of the experiment fishes skin shows that the extracted gelatin was 11.7% for yield, 85.7% for protein, 0.84% for fat , 0.65% for ash and 12.81% moisture. The physical properties of extracted gelatin such as melting point was 25.3 °C, setting points 21.8°C and 112 Sc. While the relatively viscosity was 2.5 cP, the result shows that the extracted gelatin have an ability to gelation in all concentrations, the emulsifying property increased with increasing of the concentration of the sample, the extracted gelatin have a good sensory properties with a pale Yellow color and less fish smell acceptable.

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The elastic properties such as (compressibility range from (1 to 0.6 values), isothermal bulk modulus and pressure derivative of isothermal bulk modulus) have been computed using (vinet, Birch – Murghun, Shanker, poireior)EOSs, the results were compared with the experimental data. The effect of high temperature and pressure on the four thermodynamic properties for copper have been studied. The vibration energy of atoms (ED) in a solid copper (Cu) and heat capacity at a constant volume ( CV ) have been evaluated using Debye model and the effect of pressure on Debye temperature. Finally, melting curve representing the variation of melting (Tm) with pressure have been Calculated for copper by using Mie Gruneison – Debye equation (based on the above equation of states), Lindemann and Kumer equations, also the melting gradient was computed. It is found that melting temperature increases with pressure in a non-linear manner such that the melting gradient decreases gradually with increase in pressure. The results were found in good fitting with experimental data.

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Slag of aluminum is a residue which results during the melting process of primary and secondary aluminum production. Salt slag of aluminum is hazardous solid waste according to the European Catalogue for Hazardous Wastes. Hence, recovery of aluminum not only saves the environment, but also has advantages of financial and economic returns. In this research, aluminum was recovered and purified from the industrial wastes generated as waste from both of State Company for Electrical and Electronic Industries (Baghdad/AlWaziriya) and General Company for Mechanical Industries (Babylon/-Al-Escandria). It was found that these wastes contain tiny proportions of other elements such as iron, copper, nickel, titanium, lead, and potassium. Wastes were recovered for green sustainability, saving energy and cost effectiveness. The method applied for recovering aluminum was pyro-metallurgical method by smelting and refining. X-Ray fluorescence spectroscopy and X- Ray diffraction techniques of the slag sample were used to determine the chemical analysis and phases, respectively. Melting experiments were conducted by using different types of fluxes (KAlF4, NaCl, KCl and AlCl3) at different percentages (0, 5, 10 %) and different melting temperatures (700, 750, 800oC). Design of Experiment (DOE) by Taguchi method, orthogonal array L9, was used in melting experiments. Melting efficiency of aluminum was equal to 84.7%. Electro-refining of aluminum was done by using anhydrous aluminum chloride and NaCl as ionic liquids at low temperature 100 ◦C in electro-refining method producing aluminum of 99% purity.

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