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.
Polycyclic aromatic hydrocarbons (PAHs) were measured in aerosol from air samples, which collected for the period from April 2012 to February 2013, in Baghdad city, at Daura Refinery. Aerosol samples were collected on cellulose fiber filters for 1.5 h in each site for the morning and evening time. These aerosol samples undergone soxhlet extraction.
After the extraction, 49 samples were analyzed by GC-MS in order to determin 16 PAH compounds. The parameters temperature, relative humidity and wind speed were measured during the measurement period. The PAH concentrations were different for location inside and outside Daura refinery. Naphthalene was the most abundant PAH detected in all points at the site sampling for all seasons. There i
The current study was conducted to demonstrate the effects of air pollution on different biochemical parameters in Citrus aurantium plant and calculation the Air Pollution Tolerance Index (APTI). Five sites were selected to collect plant leaves, four of them within the city of Baghdad, namely Al-Jadriya, Al-Andlous, Al-Doura and close to the private generators to represent the urban areas and Abu Ghraib site to represent the rural area. Seasonal samples were collected for the period from October 2016 to June 2017. Eleven biochemical parameters total chlorophyll, ascorbic acid, leaf extract pH, relative water content, total nitrogen, total protein content, total sugar content, proline, electrical conducti
... Show MoreIn this work, an experimental study has been done to expect the heat characteristics and performance of the forced-convection from a heated horizontal rectangular fins array to air inside a rectangular cross-section duct. Three several configurations of rectangular fins array have been employed. One configuration without notches and perforations (solid) and two configurations with combination of rectangular-notches and circular-perforations for two various area removal percentages from fins namely 18% notches-9% perforations and 9% notches-18% perforations are utilized. The rectangular fins dimensions and fins number are kept constant. The fins array is heated electrically from the base
... Show MoreShisha smoke represents one of the causes of indoor air pollution. Heavy metals represent the main components in shisha smoke. In this research study, the indoor concentrations of heavy metals in shisha smoke café sites was investigated, samples were taken from two café sites (site1, site 2) which differ in their volume. Site1 volume was 77m3, while site 2 was 437.5m3. Sample were taken by using a low volume sampler (sniffer), and then examined by the Atomic Absorption Spectrometry (AAS). The results showed that indoor air shisha smoke samples for both experimental sites have shown a significant amount of heavy metals as compared with control sampling values. The mean concentration values of (Pb, Zn, Co, Ni, Cr) in site 1 were (11.004,
... Show MoreThe ratio of draft tube to reactor diameters is of decisive importance for the operation behavior of air lift loop reactors. The influence of draft tube geometry was investigated with respect to oxygen mass transfer and mixing time. The diameter ratio was varied between 0.33 and 0.80. The measurements were performed in two loop reactors with liquid capacities of 11.775 and 26.49 liters using aqueous with solutions of different coalescence behavior. The results show that there is no single diameter ratio which would produce most favorable conditions for the two process parameters. With respect to the more important requirements of aerobic cultures, i.e high oxygen mass transfer and efficient mixing, a diameter ratio between 0.5 and 0.6 is
... Show MoreIn this study, polymeric coating was developed by incorporating nano graphene in the polymer blend with applications to oil storage tanks. The oil storage tanks samples were brought from the oil Pipeline Company / Doura refinery in Baghdad. The coating polymer was formed with a blend (epoxy resin and repcoat ZR). The proportion of mixing the mixture was 3:1:1 epoxy resin 21.06 gm: repcoat ZR 10.53 gm: hardener 10.53 gm. The blend/graphene was prepared using in stui-polymerization method with different weight percentage 1, 3, 5, and 7 wt % added to blend. The resulting solution was put in a glass tube on a magnetic stirrer for one hour at a temperature of 40 °C. The result of contact angle and wate
... Show MoreThis research dedicated to make an investigation for the variation of electron density concentration of D- region(NmD), at a characteristic height of 81 km throughout solar cycle 23, with solar activity(represented by sunspot number indices: international sunspot number(Ri), Northern hemisphere sunspot number(Rn) and Southern hemisphere sunspot number(Rs), as well as, the correlation between these indices for Baghdad city(lat.: 33.3o N, long.: 44.4o E) at local noon time during the ascending and the descending phases of solar cycle 23. A very strong directly relationship were found between Ri, Rn and Rs with NmD, as well as, the correlation coefficient between these parameters have been calculated and it has been found it is equal, i.e.,
... Show MoreThis research deals with unusual approach for analyzing the Simple Linear Regression via Linear Programming by Two - phase method, which is known in Operations Research: “O.R.”. The estimation here is found by solving optimization problem when adding artificial variables: Ri. Another method to analyze the Simple Linear Regression is introduced in this research, where the conditional Median of (y) was taken under consideration by minimizing the Sum of Absolute Residuals instead of finding the conditional Mean of (y) which depends on minimizing the Sum of Squared Residuals, that is called: “Median Regression”. Also, an Iterative Reweighted Least Squared based on the Absolute Residuals as weights is performed here as another method to
... Show MoreCommunication is one of the vast and rapidly growing fields of engineering, where
increasing the efficiency of communication by overcoming the external
electromagnetic sources and noise is considered a challenging task. To achieve
confidentiality for color image transmission over the noisy communication channels
a proposed algorithm is presented for image encryption using AES algorithm. This
algorithm combined with error detections using Cyclic Redundancy Check (CRC) to
preserve the integrity of the encrypted data. This paper presents an error detection
method uses Cyclic Redundancy Check (CRC), the CRC value can be generated by
two methods: Serial and Parallel CRC Implementation. The proposed algorithm for
the