Solar photovoltaic (PV) has many environmental benefits and it is considered to be a practical alternative to traditional energy generation. The electrical conversion efficiency of such systems is inherently limited due to the relatively high thermal resistance of the PV components. An approach for intensifying electrical and thermal production of air-type photovoltaic thermal (PVT) systems via applying a combination of fins and surface zigzags was proposed in this paper. This research study aims to apply three performance enhancers: case B, including internal fins; case C, back surface zigzags; and case D, combinations of fins and surface zigzags; whereas the baseline smooth duct represents case A. A 2D, steady-state simulation model that took into account the impact of the convective flow of air circulating inside the PVT system in addition to radiative and convective heat losses from the front PV surface was developed and validated via previous tests. The results revealed that, under the same volume requirements, the application of surface zigzags is preferred for airflow rates of 0.06 kg/s or less, whereas the introduction of fins is preferred for higher airflow rates. The results also revealed that, of the three cases considered, the introduction of the fin–surface zigzag combination is the most effective and has the potential to improve the electrical and thermal efficiency by ~26% and 3%, respectively.
Objective: The study aimed to screen the prepubertal children for idiopathic scoliosis at earlier stages, and find
out the relationship between idiopathic scoliosis and demographic data such as age, sex, body mass index,
heavy backpacks, and heart & lung diseases.
Methodology: A descriptive study was conducted on screening program for prepubertal children in primary
schools at Baghdad city, starting from 24th of February to the end of October 2010. Non- probability
(purposive) sample of 510 prepubertal children were chosen from primary schools of both sides of Al-Karkh
and Al-Russafa sectors. Data was collected through a specially constructed questionnaire format include (24)
items multiple choice questions, and
In this work, solid random gain media were fabricated from laser dye solutions containing nanoparticles as scattering centers. Two different rhodamine dyes (123 and 6G) were used to host the highly-pure titanium dioxide nanoparticles to form the random gain media. The spectroscopic characteristics (mainly fluorescence) of these media were determined and studied. These random gain media showed laser emission in the visible region of electromagnetic spectrum. Fluorescence characteristics can be controlled to few nanometers by adjusting the characteristics of the host and nanoparticles as well as the preparation conditions of the samples. Emission of narrow linewidth (3nm) and high intensity in the visible region (533-537nm) was obtained.
A total of 30 specimens of house sparrow Passer domesticus biblicus Hartert, 1904 (15 females and 15 males) were collected from gardens of some houses in Baghdad city; all birds were dissected to identify the parasites in vesicle, gizzard, intestine, gall bladder and caecum. One species of trematodes Brachydistomum microscelis (Yamaguti, 1933) was found in the gall bladder and two species of cestodes Anonchotaenia globata (von Linstow, 1879) and Raillietina tetragona (Molin, 1858) were found in the small intestine of house sparrow. Morphologic and morphometric measurements were considered.
The genus Brachydistomum Travassos, 1944 is being recorded for the first time in Iraq in the gall bladder of house sparr
... Show MoreThe uses of traditional plant extract in the treatment of various diseases have been flourished. The present study, IJSR, Call for Papers, Online Journal
The virulent genes are the key players in the ability of the bacterium to cause disease. The products of such genes that facilitate the successful colonization and survival of the bacterium in or cause damage to the host are pathogenicity determinants. This study aimed to investigate the prevalence of virulence factors (esp, agg, gelE, CylA) in E. faecalis isolated from diverse human clinical collected in Iraqi patient , as well as to assess their ability to form biofilm and to determine their haemolytic and gelatinase activities. Thirty-two isolates of bacteria Enterococcus faecalis were obtained, including 15 isolates (46.87%) of the urine, 6 isolates (18.75%) for each of the stool and uterine secretions, and 5 isolates (15.62%) of the wo
... Show MoreThe purpose of this paper is to find the best multiplier approximation of unbounded functions in –space by using some discrete linear positive operators. Also we will estimate the degree of the best multiplier approximation in term of modulus of continuity and the averaged modulus.
We aimed to obtain magnesium/iron (Mg/Fe)-layered double hydroxides (LDHs) nanoparticles-immobilized on waste foundry sand-a byproduct of the metal casting industry. XRD and FT-IR tests were applied to characterize the prepared sorbent. The results revealed that a new peak reflected LDHs nanoparticles. In addition, SEM-EDS mapping confirmed that the coating process was appropriate. Sorption tests for the interaction of this sorbent with an aqueous solution contaminated with Congo red dye revealed the efficacy of this material where the maximum adsorption capacity reached approximately 9127.08 mg/g. The pseudo-first-order and pseudo-second-order kinetic models helped to describe the sorption measure
Objective(s): The aims of present study to findout the effect of aeromedical evacuation program on flight medics’ knowledge.
Methods: A pre-experimental design is carried in army aviation bases in Iraq, for the period of April 1st 2019 to October 25th 2019. Non-probability "purposive" sample of (30) flight medics are selected from army aviation bases. The questionnaire consisted of two main parts: the demographic characteristics of air paramedics, and the second part included five axes, which are (50) paragraphs related to the knowledge of air paramedics towards emergency injuries. The researcher used the statistical program version 20 to analyze the data, and the stability of the questionnaire was measured through the pre and post
The intelligent buildings provided various incentives to get highly inefficient energy-saving caused by the non-stationary building environments. In the presence of such dynamic excitation with higher levels of nonlinearity and coupling effect of temperature and humidity, the HVAC system transitions from underdamped to overdamped indoor conditions. This led to the promotion of highly inefficient energy use and fluctuating indoor thermal comfort. To address these concerns, this study develops a novel framework based on deep clustering of lagrangian trajectories for multi-task learning (DCLTML) and adding a pre-cooling coil in the air handling unit (AHU) to alleviate a coupling issue. The proposed DCLTML exhibits great overall control and is
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