Preferred Language
Articles
/
YBim3JYBVTCNdQwCuoek
Assessment of using different ozone-friendly R22 alternative refrigerants in residential air conditioners in a high-ambient temperature country
...Show More Authors
Abstract<p>The performance of a vapor compression refrigeration system (VCRS)-based residential air conditioner operating in a high-ambient temperature (HAT) country was investigated using six zero-ODP (ozone depletion potential) refrigerants as replacements to R22. The non-flammable alternative refrigerants considered in the present research were R134a, R404A, R407C, R410A, R448A, and R507A. Using the basic conservation laws, the VCRS was modeled during steady-state operation and solved using engineering equation solver (EES) software. Coefficient of performance (COP), pressures and temperatures at compressor suction and discharge, Global Warming Potential (GWP), critical pressure and temperature, compressor pressure ratio, volumetric cooling capacity (VCC) specific cooling capacity (SCC), and refrigeration effect were utilized as assessment criteria for the alternative refrigerants considered. From these refrigerants, the highest values of suction pressure, discharge temperature, and condenser pressure were attained by R410A. In addition, the discharge temperatures for all refrigerants, except R134a, were all higher than their corresponding critical values, causing a quicker drop in the VCRS’s performance. As an alternative refrigerant, R407C showed the highest SCC of 141.0 kJ/kg followed directly by 139.2 and 138.0 kJ/kg for R410A and R448A, respectively. A reverse trend was found for VCC with respective values of 4722 and 3775 kJ/m<sup>3</sup> for R410A and R448A. Lower volume flow rates and smaller-sized compressors are expected for higher VCC refrigerants. The same trend was found for the compressor’s specific work input and condenser’s specific heat transfer with values of (51.14, 46.82, and 45.38 kJ/kg) and (190.3, 187.8, and 183.4 kJ/kg) for R410A, R407C, and R448A, respectively. For applications in HAT countries, larger condenser’s specific heat transfer makes the refrigerant more applicable. Conversely, with respect to COP, refrigerant R134a with a value of 3.075 was the superior alternative followed by R448A and R407C with respective COPs of 3.042 and 3.011. Based on the overall assessment in terms of environmental obligation, COP, compressor input power, refrigerant flow rate required, and all the evaluations made in this research, refrigerant R448A was recommended as the most appropriate substitute to R22 which can effectively be used in residential air conditioners in a HAT country.</p>
Scopus Crossref
View Publication
Publication Date
Mon Sep 01 2008
Journal Name
Al-khwarizmi Engineering Journal
Design and Simulation of GaussianFSK Transmitter in UHF Band Using Direct Modulation of ΣΔ Modulator Fractional-N Synthesizer
...Show More Authors

This research involves design and simulation of GaussianFSK transmitter in UHF band using direct modulation of ΣΔ  fractional-N synthesizer with the following specifications:

Frequency range (869.9– 900.4) MHz, data rate 150kbps, channel spacing (500 kHz), Switching time 1 µs, & phase noise @10 kHz = -85dBc.

New circuit techniques have been sought to allow increased integration of radio transmitters and receivers, along with new radio architectures that take advantage of such techniques. Characteristics such as low power operation, small size, and low cost have become the dominant design criteria by which these systems are judged.

A direct modulation by ΣΔ  fractional-N synthesizer is proposed

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Rawal Medical Journal
Procalcitonin Level In COVID-19 Patients: A single center study
...Show More Authors

Objective: The study the association of procalcitonin (PCT) and c-reactive protein (CRP) levels in COVID-19 patients and it's role as a guide in progress and management of those patients. Methodology: This cross-sectional study analyzed 200 CIOVID-19 patients in a single privet center in Baghdad, Iraq from January 1, 2021 to January 1, 2022. Demographic data like age, sex, and clinical symptoms were recorded. High sensitivity CRP and PCT in the serum were measured via dry fluorescence immunoassay (Lansionbio-China). Results: Out of 200 patients, 50 had moderate Covid and 150 had severe disease. Mean serum PCT levels was 0.039±0.05 ng/mL in the moderate group (range 0.011-0.067) and 0.43±0.21 ng/mL in the severe group (range 0.21

... Show More
View Publication
Scopus Crossref
Publication Date
Fri Mar 21 2025
Journal Name
Iklil For Human Studies
Review Article A Feminist Gothic in the American Literary Fiction
...Show More Authors

Teresa Fitzpatrick presents a connection between oppressed women and the plant of Wisteria in gothic fiction in her article “Wisteria: A Female Eco-Gothic Metaphor in American Fiction Through the Ages.” The connection between women and nature is common in literature as women are usually compared to the beauty or ferocity of flowers, rivers, or natural phenomena in general. The connection extends to the architecture and sort of plants that appear in gothic literature. Gothic novels have routinely been connected to the secrets and life stories of women who cannot have the liberty to live or share them outside their homes. A fearful house with a prisoned person, ghost, or a secret is mostly normally found in gothic writing. Women have exce

... Show More
Preview PDF
Publication Date
Wed Oct 02 2024
Journal Name
Translation&linguistics
Verbal forms in French and Iraqi Arabic: a contrastive study
...Show More Authors

View Publication Preview PDF
Publication Date
Wed Aug 31 2022
Journal Name
Al-kindy College Medical Journal
A Population based Study on Self Medication Practice in Pakistan
...Show More Authors

Background: The risk of antibiotics resistance (AR) increases due to excessive of antibiotics either by health care provider or by the patients.

Objective: The assessment of the self-medication Practice of over the counter drugs and other prescription drugs and its associated risk factor.

Subjects and Methods: Study design: A descriptive study was conducted from “20th December 2019 to 08th January 2021”. A pre validated and structured questionnaire in English and Urdu language was created to avoid language barrier including personal detail, reasons and source and knowledge about over the counter drugs and Antibiotics. Sample of the study was randomly selected.

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
International Conference On Scientific Research &amp; Innovation (icsri 2022)
Saccharomyces Cerevisiae as a human pathogen in renal transplant recipients
...Show More Authors

View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Al–bahith Al–a'alami
The Communicative Integration in New Media: Building a Communicative Model
...Show More Authors

The internet, unlike other traditional means of communication, has a flexibility to stimulate the user and allows him to develop it. Perhaps, the reason for the superiority of the internet over other traditional means of communication is the possibility of change and transmission from one stage to another in a short period. This means that the internet is able to move from the use to the development of the use and then the development of means and innovation as the innovation of the internet is a logical product of the interaction of the user with the network. The internet invests all the proposals and ideas and does not ignore any even if it is simple. This is represented in social networking sites which in fact reflects personal emotio

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Oct 01 2015
Journal Name
Al–bahith Al–a'alami
Correspondents and Professional Standards in News Coverage (A Field Study)
...Show More Authors

         The essence of the new work in the satellite TV channels is to provide news coverage of news that will inform the people of what is going on around them in order to increase their political, social, economic and cultural awareness and this drives them to take positions or certain behaviors on according to what the communicator in these channels wants. News and news reports are generally used as a psychological variable to influence public opinion and does not offer interestingness and information. Therefore, satellite TV channels have assumed special attention towards their correspondents desiring to achieve scoop in news coverage and to have the final word in reading events and install it

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Apr 26 2021
Journal Name
Open Access Macedonian Journal Of Medical Sciences
Three-dimensional printing applications in the neurosurgery: A pilot study
...Show More Authors

BACKGROUND: Three-dimensional (3D) printing is an evolving technology that has been used recently in a wide spectrum of applications. AIM: The objective is to evaluate the application of 3D printing in various neurosurgical practice. PATIENTS AND METHODS: This pilot study was conducted in the neurosurgical hospital in Baghdad/Iraq between July 2018 and July 2019. An X, Y, and Z printer was used. The working team included neurosurgeons, biomedical engineers, and bio-technicians. The procedure starts with obtaining Magnetic resonance imaging (MRI) or computed tomography (CT) scan in particular protocols. The MRI, and CT or angiography images were imported into a 3D programmer for DICOM images called 3D slice where these files con

... Show More
View Publication
Scopus (4)
Crossref (3)
Scopus Crossref
Publication Date
Fri Dec 30 2016
Journal Name
Al-kindy College Medical Journal
Congenital Thrombasthenia In Children Welfare Teaching Hospital: A Descriptive Study
...Show More Authors

Background: Thrombasthenia is an inherited genetic disorder affecting platelets, which is characterized by spontaneous muco-cutaneous bleeding and abnormally prolonged bleeding in response to injury or trauma. Objectives: The aim of this study was to assess the diagnosis and treatment of thrombasthenia in Children Welfare Teaching Hospital. Type of the study: A cross-sectional study. Methods: This descriptive study was performed on 66 patients with thrombasthenia from the first of October 2013 till the first of July 2015.The diagnosis of the disease was done by a wide spectrum of characteristics including family history, clinical manifestations, laboratory tests.. Results: The common manifestations of the disease at time of diagnosis wer

... Show More
View Publication Preview PDF