The present work includes design, construction and operates of a prototype solar absorption refrigeration system, using methanol as a refrigerant to avoid any refrigerant that cause global warming and greenhouse effect. Flat plate collector was used because it’s easy, ninexpensive and efficient. Many test runs (more than 50) were carried out on the system from May to October, 2013; the main results were taken between the period of July 15, 2013 to August 15, 2013 to find the maximum C.O.P, cooling, temperature and pressure of the system. The system demonstrates a maximum generator temperature of 93.5 oC, on July 18, 2013 at 2:30 pm, and the average mean generator temperature Tgavr was 74.7 °C, for this period. The maximum pressure Pg obtained was 2.25 bar on July 19, 2013 at 2:00 pm. The current system shows cooling capacity of 0.15 ton with coefficient of performance of 0.48, and minimum evaporator temperature obtained was 14.2oC. A comparison of the present with previous works, showed that most of the previous work used ammonia as the main refrigerant, and even that used methanol it was as aqua methanol, or to be part of pair refrigerant, while the present work use the methanol as the main and the only refrigerant in the system. The results and the factors that provided by the current work, give a good understanding for using the methanol as a refrigerant with the solar absorption system. And the system can work in continuous operation cycle. This work gave fundamental understanding for designing solar refrigeration system, by using the results of present study to design air-conditioning unit, with one ton capacity, using the solar energy, and the methanol as a refrigerant.
Firstly, in this study, a brief updated description and applications of different solar collectors used in renewable energy systems for supplying electric and thermal energy was presented. Secondly, an attempt was made to utilize tilting orientation of solar collector for maximizing collector energy with time in respect to horizontal orientation. For energy calculation, global solar radiation was used since they are directly related. For that purpose, field measurements of half-hourly radiation on two flat panels of tilting and horizontal orientations were carried out throughout 8-month period under local climate of Baghdad. Then, energy gain and radiation level averages were calculated based on the field radiation
... Show MoreIn this study, a different design of passive air Solar Chimney(SC)was tested by installing it in the south wall of insulated test room in Baghdad city. The SC was designed from vertical and inclined parts connected serially together, the vertical SC (first part) has a single pass and Thermal Energy Storage Box Collector (TESB (refined paraffin wax as Phase Change Material(PCM)-Copper Foam Matrix(CFM))), while the inclined SC was designed in single pass, double passes and double pass with TESB (semi refined paraffin wax with copper foam matrix) with selective working angle ((30o, 45o and 60o). A computational model was employed and solved by Finite Volume Method (FVM) to simulate the air i
... Show MoreIn this work, a functional nanocomposite consisting of multi walled carbon nanotubes combined with nanoparticles of silver and Pomegranate peel extract (MWCNTs- SNPs -NPGPE) was successfully synthesized using ultra sonic technique. The nanocomposite has been characterized using Transmission electron microscope (TEM), XRD, Energy dispersive X-ray spectroscopy (EDS) UV-Vis and FTIR. The obtained results reveal that the MWCNTs-SNPs-NPGPE nanocomposite exhibits form of nanotubes with rough surfaces and containing black spots, which are the silver nanoparticles. The dimensions of this tube are 161 nm in length and 60 nm in width with nanoparticles of silver not exceeding 20 nm. The XRD pattern of the prepared MWCNTs-SNPs-NPGPE nanocomposite s
... Show MoreThe effect of approaching nozzle jet from the deposition surface
on structural, optical and morphology properties of copper oxide thin
films was studied. The film was prepared by homemade fully
computerized CNC spray pyrolysis deposition technique at
preparations speed (3, 4, 5, and 6 mm/sec). The repeated line mode
was used at deposition temperature equal 450 °C whereas the
spraying time was in the range of (15-30 min) according to the
deposition speed. The film exhibit polycrystalline structure with
preferred orientation along (-111), (022) and (011), (002) at a 2θ
value of (35.63o) and (38.8o) respectively. Optical band gaps were
recorded at these speed shows variance in value from (1.53-2.08 eV).
Fi
Image of landsate-7 taken by thematic mapper was used and classified using supervised method. Results of supervised classification indicated presence of nine land cover classes. Salt-soils class shows the highest reflectance value while water bodies' class shows the lowest values. Also the results indicated that soil properties show different effects on reflectance. There was a high significant positive relation of carbonate, gypsum, electric conductivity and silt content, while there was a week positive relation with sand and negative relation with organic matter, water content, bulk density and cataion exchange capacity.
This study was conducted at the College of Education for Pure Sciences (Ibn Al-Haitham), University of Baghdad. The aim of this study was to isolate and diagnose fungi from fish feedstuff samples, and also detection of aflatoxin B1 and ochratoxin A in fish muscles and feedstuffs. Randomly, the samples were collected from some fish farms from Baghdad, Babil, Wasit, Anbar, and Salah al-Din provinces. This study included the collection of 35 feedstuff samples and 70 fish muscle samples, and each of the two fish samples fed on one sample of the feedstuff. The results showed the presence of several genera of different fungi including Aspergillus spp, Mucor spp., Penicillium spp., Yeast spp., Fusarium spp., Rhizopus spp., Scopiolariopsis spp., Ep
... Show MoreThis research aims to identify the effectiveness of counseling by using the technique of self-talkin developing the habits of mind among middle school students by testing important hypotheses, and choosing the experimental design for the two groups (experimental - control). The classification of "Costa & Kallick" was adopted to measure the habits of the mind, and the scale consisted of (64) items, and after confirming the psychometric properties of the scale, the researcher applied it to the research sample (487) students from middle school students. One of the students who got the lowest marks after answering the scale. purpose of applying the experiment. He divided them into two groups, one of them is experimental (10) students, as
... Show MoreKE Sharquie, AA Noaimi, ZN Al-Khafaji…, Journal of Cosmetics, Dermatological Sciences and Applications, 2016 - Cited by 2
Image of landsate-7 taken by thematic mapper was used and classified using supervised method. Results of supervised classification indicated presence of nine land cover classes. Salt-soils class shows the highest reflectance value while water bodies' class shows the lowest values. Also the results indicated that soil properties show different effects on reflectance. There was a high significant positive relation of carbonate, gypsum, electric conductivity and silt content, while there was a week positive relation with sand and negative relation with organic matter, water content, bulk density and cataion exchange capacity.