Preferred Language
Articles
/
joe-733
Experimental Study on Double-Pass Solar Air Heater with and without using Phase Change Material
...Show More Authors

In this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant air mass flow rate of (0.0375 kg/sec). The parameters that affect the thermal performance of the SAH with and without the PCMs presented by solar radiation, the difference in air temperature, outlet air temperature, instantaneous thermal efficiency, and daily efficiency are evaluated. The experimental results show that when using the PCM, the temperature of the outlet air was enhanced and increased over the ambient temperature by (1.5 - 6.5 C) after sunset for 5 hours period. It was found that the instantaneous thermal efficiency of the heater using thermal storage exceeds 100% after sunset, this is due to a large amount of heat stored in the paraffin wax that has been released during the discharge process. Also, it was found that the daily efficiency of the double pass SAH integrated with and without thermal energy storage unit was (56, 47%) respectively.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jun 01 2023
Journal Name
Effect Of Dna Damage Mediating Psychosocial Stress On Aging
Effect of DNA damage mediating psychosocial stress on aging
...Show More Authors

Adversity and psychosocial stress are involved in aging through the following pathways. psychological stress enhances the nerve system to secrete endocrine mediators (hormones). Mitochondrial respiration mediates energy production stimulated by binding to these hormones to their receptors. Energy produced by mitochondria accelerates metabolism and, in its turn, leads to increases in reactive oxygen species (ROS) of free radicals. Cellular stress and accumulation of damage can result from an excess of ROS. Accumulation of damage comprises damages in telomeric and nontelomeric DNA, in addition to mitochondrial DNA. Mitochondrial DNA damage plays an important role in increasing the pathway of p53/p21. The expression of the PGC-1α gene is inhi

... Show More
Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Antimicrobial activity of propolis agents on some pathogenic microbes
...Show More Authors

The study aims to investigate the antimicrobial activity of propolis obtained from different regions of Iraq compared with that of propolis obtained from Iran. Samples were investigated for their antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Eschericha coli, Klebsiella pneumoniae, Bacillus cereus , Staphylococcus epidermidis and Candida albicans using standard antimicrobial assays. Marked variations in the antimicrobial activity of the different propolis samples were observed, the method of extraction selected gives the highest antimicrobial activity and the best alcohol concentration using in the extraction of propolis , then the crude extract of propolis showed synergistic effect with some antibiotics in

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Effects of ethanol on the hippocampus of rat Brain
...Show More Authors

ten albino male rates were orally treated daily 20% and 30% ethanol for 30 days treatment with 30%ethanol caused of hippocampuse of darckness google hospital patients

View Publication Preview PDF
Publication Date
Thu Jul 01 2021
Journal Name
Journal Of Physics: Conference Series
Generalized Γ-n-Derivations on Prime Γ-Near-Rings
...Show More Authors
Abstract<p>The main purpose of this paper is to define generalized Γ-n-derivation, study and investigate some results of generalized Γ-n-derivation on prime Γ-near-ring G and <italic>K</italic> be a nonzero semi-group ideal of <italic>G</italic> which force G to be a commutative ring.</p>
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Mon Feb 01 2021
Journal Name
Iop Conference Series: Materials Science And Engineering
The influence of incorporating recycled brick on concrete properties
...Show More Authors
Abstract<p>One of the major problems in modern construction is the accumulation of construction and demolition waste; this study thus examines the consumption of waste brick in concrete based on the use of blended nano brick powder as replacement for cement and as a fine aggregate. Seven concrete mixes were developed according to ACI 211.1 using recycled waste brick. Nano powder brick at 0, 5, and 10% was used as a replacement by cement weight, with other mixes featuring 10, 20, and 30% partial replacement by volume of river sand with brick. The experimental results for replacement of cement with nano brick powder showed an enhancement in mechanical properties (compressive, flexural, and tensile strength) at 7,</p> ... Show More
View Publication
Crossref (5)
Crossref
Publication Date
Sat Dec 28 2024
Journal Name
Medicni Perspektivi
The impact of Sudafed on spleen of albino mice
...Show More Authors

Pseudoephedrine (PSE), often known as Sudafed, belongs to a class of medications known as sympathomimetic amines, which affect the digestive system, respiratory system, and cardiovascular system. This drug has a long history of medical use; it is helpful in treating symptoms of the common cold and flu, sinusitis, asthma, and bronchitis. Due to its central nervous system (CNS) stimulant properties and structural similarity to amphe­tamine, it is also used for non-medical purposes such as doping agent, to increase focus, and as a substance that gets rid of exhaustion and drowsiness. Nevertheless only a few studies, backed up its impact on solid abdominal organs. The aim of this task is to investigate the effect of some dosages of PSE

... Show More
Scopus Clarivate Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Proposed methods of image recognition depend on the PCA
...Show More Authors

This paper suggest two method of recognition, these methods depend on the extraction of the feature of the principle component analysis when applied on the wavelet domain(multi-wavelet). First method, an idea of increasing the space of recognition, through calculating the eigenstructure of the diagonal sub-image details at five depths of wavelet transform is introduced. The effective eigen range selected here represent the base for image recognition. In second method, an idea of obtaining invariant wavelet space at all projections is presented. A new recursive from that represents invariant space of representing any image resolutions obtained from wavelet transform is adopted. In this way, all the major problems that effect the image and

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Dec 18 2019
Journal Name
Baghdad Science Journal
Orthogonal Symmetric Higher bi-Derivations on Semiprime Г-Rings
...Show More Authors

   Let M is a Г-ring. In this paper the concept of orthogonal symmetric higher bi-derivations on semiprime Г-ring is presented and studied and the relations of two symmetric higher bi-derivations on Г-ring are introduced.

View Publication Preview PDF
Crossref (1)
Clarivate Crossref
Publication Date
Thu Feb 02 2012
Journal Name
Education College Journal/al-mustansiriyah University
On Significance Testimator in Pareto Distribution Via Shrinkage Technique
...Show More Authors

In this paper, preliminary test Shrinkage estimator have been considered for estimating the shape parameter α of pareto distribution when the scale parameter equal to the smallest loss and when a prior estimate α0 of α is available as initial value from the past experiences or from quaintance cases. The proposed estimator is shown to have a smaller mean squared error in a region around α0 when comparison with usual and existing estimators.

Preview PDF
Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The influence of human resources Accounting on cost reduction
...Show More Authors

The development of human resources training programs has an applied and important role in the preparation of human cadresin terms of capacity to absorb technical sciences and skills and scientific and practical practices at faster rates in order to bealighed with continous development. Hence the recognition of the significant role that human resources play in the economy of any country,which has stressed the interest towards the economic unity of the qualified staff that it needsin atimely manner through the ongoing training process in the era of high technology day by  day  In this regard ,the current research deal with accounting of human resources and its impact on reducing costs in the military establishment and the

... Show More
View Publication Preview PDF
Crossref