The thermal performance of a flat-plate solar collector (FPSC) using novel heat transfer fluids of aqueous colloidal dispersions of covalently functionalized multi-walled carbon nanotubes with β-Alanine (Ala-MWCNTs) has been studied. Multi-walled carbon nanotubes (MWCNTs) with outside diameters of (< 8 nm) and (20–30 nm) having specific surface areas (SSAs) of (500 m2/g) and (110 m2/g), respectively, were utilized. For each Ala-MWCNTs, waterbased nanofluids were synthesized using weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1%. A MATLAB code was built and a test rig was designed and developed. Heat flux intensities of 600, 800, and 1000 W/m2; mass flow rates of 0.6, 1.0, and 1.4 kg/min; and inlet fluid temperatures of 30, 40, and 50°C were used to perform the test runs. Using water and nanofluids, the efficiency of the FPSC was found to increase with the increase in heat flux intensity and flow rate, and decrease with the increase in inlet fluid temperature. When applying nanofluids in the FPSC and as weight concentration and SSA increased, a reduction in the values of absorber plate temperature (AP) and tube wall temperature (TW) was observed down to 2.86% and 3.03%, respectively, while the FPSC’s efficiency increased up to 9.55% for 0.1-wt% Ala-MWCNTs < 8 nm at 1.4 kg/min, compared with water. Good agreement was obtained between the experimental values and MATLAB code predictions for AP, TW, and efficiency with maximum differences of 3.02%, 3.19%, and 3.26% for water, and 4.24%, 3.94%, and 12.64% for nanofluids, respectively. Consequently, the MATLAB code was judged suitable for modeling the nanofluid-based FPSC with suitable precision. It was proved that the positive effects of using nanofluids in the FPSC were higher their negative effects on pressure drop because all the calculated values of performance index (PI) were more than 1. As weight concentration and SSA increased, PI increased up to 1.095 for 0.1-wt% Ala-MWCNTs < 8 nm. Therefore, it was concluded that the nanofluids considered in this research can usefully be employed as working fluids in FPSCs for improved thermal performance, and the 0.1-wt% water-based Ala-MWCNTs < 8 nm nanofluid was fairly the distinguished one.
This study deals with knowing the types of research in public relations studies at the Faculty of Mass Communication for the period from 1989 to 2007 and knowing the methods that researchers used in their studies, as well as knowing the methods and tools of scientific research that were used, and whether one method or tool is used more than others, and knowing Samples used in the analysis. As well as the contents and types of this research The institutions that were subjected to the study, and the preparation of the respondents This research aims to answer the following questions:. A- What are the types of research and methods that were used in university theses that dealt with the topic? Public Relations at the Faculty of Media from 1989
... Show MoreBackground: Routine supplementation of vitamin D to infants is justifiable since vitamin D deficiency, and its consequences are highly prevalent not only in developing countries but worldwide. Maintaining a normal level of vitamin D is crucial in order to have a normal skeletal, as well as, extra-skeletal health. Knowledge of mothers regarding importance of vitamin D supplementation affect the health of their babies in a positive manner if accompanied by appropriate practice.
Objective: To determine the level of knowledge, attitude and practice of Iraqi mothers of under or equal 12 months old infants in Baghdad, AL-Rusafa, regarding vitamin D supplementation for their infants.
Typ
... Show MoreBackground: COVID-19 pandemic has influenced all life aspects; Dental staff, like other healthcare providers, may be exposed to COVID-19 as part of their work and its psychological impacts on healthcare workers should not be ignored
Objectives: To assess the anxiety, and fear from COVID-19 pandemic in dentists working in specialist dental centers: sample the Al-Resafa health directorate, and its relation between the anxiety, and COVID-19 fear with some of their demographic variables
Subjects and Methods: A cross-sectional study was conducted on 2nd Jan. to 14th Feb. 2021, by an electronic version of questionnaire through Google-form; the questionnaire was formed based on Mental-Health-American-Org
... Show MoreObjective: To identify the effectiveness of instruction oriented intervention for primipara women upon episiotomy and self
perineal care.
Methodology: A quasi-experimental study was carried out to determine the effectiveness of instruction-oriented
intervention for primipara women upon episiotomy and self-perineal care. A purposive "non-probability" sample of (60)
primipara mothers was selected from Ibn AL-Balady Pediatric and Maternity Hospital, Al-russafa, Baghdad. The sample
has been divided into two groups; (30) primipara women who were considered as a study group, and another (30) primipara
women who were considered as a control one. The study group was exposed to an instruction-oriented intervention. While,
the
The crystal compounds Tl2-xAg2-ySryBayCa2Cu3O10+& are successfully prepared in different concentrations (x, y=0.1, 0.2, 0.3, 0.4, 0.5) by solid state reaction process. The samples were then subjected to Nano technique under hydrolic pressure 8 ton/cm2. samples have been annealed in (850 C0) for 72 hours. The results show a best value at x, y=0.3 ratio of Ag, Ba. Electrical resistivity at x, y= 0.3 of Ag, Ba are obtained when the best value of Tc= 141 K. Samples morphology were also observed by AFM (in three dimensions), the best value of Nano is 91.74 nm at x, y= 0.3. Morphological structures of the surface were also observed by (SEM) and (EDX) show that there are dark regions and light which indicate the presence of heavy elements a
... Show MoreObjective(s): To assess women’s knowledge about health promotion after a cesarean delivery and to determine the association between women’s knowledge and their demographic data of age, level of education, and monthly income.
Methodology: A descriptive design is carried out to assess women’s knowledge about health promotion after cesarean delivery at Maternity and Pediatric Hospital in Al-Samawa City. This study starts from 26th of September 2020 up to 16th March 2021. Sample of (100) woman who are at reproductive age, pregnant (prime or multipara) who have planned to have birth by elective cesarean section or had previous elective caesarian section without medical indication or women who had cesarean section with medical indicat
Disasters, crises and wars are a serious and unforeseen threat. The capacity of the early warning system to monitor such crises is therefore crucial. The ability to make quick decisions in a short time is necessary to prevent crises from occurring. Here, the role and effectiveness of the early warning system emerges through its ability to monitor, record and analyze signals. It can also be evidenced by its ability to immediately convey these indicators to the concerned authorities to take measures that ensure these conflicts and disasters do not worsen. The system’s ability to detect disasters and crises, identify the crisis and its type, and use the scientific method and common sense to deal with it is something that contributes to findi
... Show MoreAs tight gas reservoirs (TGRs) become more significant to the future of the gas industry, investigation into the best methods for the evaluation of field performance is critical. While hydraulic fractured well in TRGs are proven to be most viable options for economic recovery of gas, the interpretation of pressure transient or well test data from hydraulic fractured well in TGRs for the accurate estimation of important reservoirs and fracture properties (e.g. fracture length, fracture conductivity, skin and reservoir permeability) is rather very complex and difficult because of the existence of multiple flow profiles/regimes. The flow regimes are complex in TGRs due to the large hydraulic fractures n
In the present paper, chitosan Schiff base has been synthesized from chitosan’s reaction with the salicyldehyde. The AuNPs was manufacture by extract of onion peels as a reducing agent. The Au NPs that have been prepared were characterized through the UV-vis spectroscopy, XRD analyses and SEM microscopy. The polymer blends of the chitosan Schiff base / PVP has been prepared through using the approach of solution casting. Chitosan Schiff base / PVP Au nano-composites was prepared. Nano composites and polymer blends have been characterized by FTIR which confirm the formation of Schiff base by revealing a new band of absorption at 1651cm-1 as a result of the (C=N) imine group. SEM, DSC and TGA confirms the thermal stability of
... Show MoreIn this work, the calculation of matter density distributions, elastic charge form factors and size radii for halo 11Be, 19C and 11Li nuclei are calculated. Each nuclide under study are divided into two parts; one for core part and the second for halo part. The core part are studied using harmonic-oscillator radial wave functions, while the halo part are studied using the radial wave functions of Woods-Saxon potential. A very good agreement are obtained with experimental data for matter density distributions and available size radii. Besides, the quadrupole moment for 11Li are generated.