Preferred Language
Articles
/
alkej-24
The Effect of Restriction Shape On Laminar Natural Convection Heat Transfer In A Vertical Circular Tube
...Show More Authors

Natural convection heat transfer is experimentally investigated for laminar air flow in a vertical circular tube by using the boundary condition of constant wall heat flux in the ranges of (RaL) from (1.1*109) to (4.7*109). The experimental set-up was designed for determining the effect of different types of restrictions placed at entry of heated tube in bottom position, on the surface temperature distribution and on the local and average heat transfer coefficients. The apparatus was made with an electrically heated cylinder of a length (900mm) and diameter (30mm). The entry restrictions were included a circular tube of same diameter as the heated cylinder but with lengths of (60cm, 120cm), sharp-edge and bell-mouth. The surface temperature along the cylinder surface for same heat flux would be higher values for circular restriction with length of (120cm) and would be smaller values for bell-mouth restriction. The results show that the local Nusselt number (Nux) and average Nusselt numberare higher for bell-mouth restriction and smaller values for (120cm) restriction. For all entry shape restrictions, the results show that the Nusselt number values increases as the heat flux increases. From the present work an empirical correlations were obtained in a form of (Log) versus (Log) for each case investigated and obtained a general correlation for all cases which reveals the effect of restriction existence on the natural convection heat transfer process in a vertical circular tube.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Jul 01 2026
Journal Name
Journal Of Materials In Civil Engineering
Optimum Proportions and Properties of Foamed Concrete Made with Waste Plastic as Fine and Coarse Aggregate
...Show More Authors

This research aimed to explore the use of foamed concrete (FC), a lightweight concrete, by replacing sand with crushed plastic from washing machines to improve environmental and thermal properties. The primary components included traditional materials like cement, water, and a foaming agent, along with the innovative use of waste plastic (WP). Utilizing Minitab software, the study applied the Response Surface Method to optimize mix designs, reducing the experimental mixtures to 31, which were then tested for dry density, porosity, water absorption, shrinkage, compressive strength, splitting tensile strength, and thermal conductivity. Results indicated a significant 24% reduction in dry density when using plastic as fine and coarse aggregate

... Show More
View Publication
Crossref (1)
Scopus Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Russian Journal Of General Chemistry
Preparation, Characterization, and Biological Activity of Mixed Schiff Base Ligand Complexes with Amino Acid L-Proline
...Show More Authors

View Publication
Scopus (11)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Sat Feb 01 2020
Journal Name
Journal Of Water Process Engineering
Waterworks sludge-filter sand permeable reactive barrier for removal of toxic lead ions from contaminated groundwater
...Show More Authors

Scopus (217)
Crossref (195)
Scopus Clarivate Crossref
Publication Date
Sat Apr 01 2023
Journal Name
Journal Of Engineering
Moisture Susceptibility of Hot Mix Asphalt Mixtures Modified by Nano Silica and Subjected to Aging Process
...Show More Authors

Moisture damage is described as a reduction in stiffness and strength durability in asphalt mixtures due to moisture. This study investigated the influence of adding nano silica (NS) to the Asphalt on the moisture susceptibility of hot-mix-asphalt (HMA) mixtures under different aging conditions. NS was mixed with asphalt binder at concentrations of 2%, 4%, and 6% by weight of the binder. To detect the microstructure changes of modified Asphalt and estimate the dispersion of NS within the Asphalt, the field emission scanning electron microscope (FE-SEM) was used. To examine the performance of Asphalt mixed with NS at different aging stages (short-term and long-term aging), asphalt mixture tests such as Marshall stability,

... Show More
View Publication Preview PDF
Scopus (24)
Crossref (12)
Scopus Crossref
Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Structural and optical properties of CdO and CdO0.99Cu0.01 thin films prepared by pulsed laser deposition technique
...Show More Authors

Structural and optical properties of CdO and CdO0.99Cu0.01 thin
films were prepared in this work. Cadmium Oxide (CdO) and
CdO0.99Cu0.01semiconducting films are deposited on glass substrates
by using pulsed laser deposition method (PLD) using SHG with Qswitched
Nd:YAG pulsed laser operation at 1064nm in 6x10-2 mbar
vacuum condition and frequency 6 Hz. CdO and CdO0.99Cu0.01 thin
films annealed at 550 C̊ for 12 min. The crystalline structure was
studied by X-ray diffraction (XRD) method and atomic force
microscope (AFM). It shows that the films are polycrystalline.
Optical properties of thin films were analyzed. The direct band gap
energy of CdO and CdO0.99Cu0.01 thin films were determined from
(αhυ)1/2 v

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Mon Jan 01 2024
Journal Name
2nd International Conference For Engineering Sciences And Information Technology (esit 2022): Esit2022 Conference Proceedings
Numerical solution to inverse coefficient problem for hyperbolic equation under overspecified condition of general integral type
...Show More Authors

View Publication
Scopus (5)
Crossref (6)
Scopus Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Theoretical Discussion of Electron Transport Rate Constant at TCNQ / Ge and TiO<sub>2</sub> System
...Show More Authors

View Publication
Scopus (15)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Fri Sep 01 2017
Journal Name
Journal Of Bridge Engineering
Novel Demountable Shear Connector for Accelerated Disassembly, Repair, or Replacement of Precast Steel-Concrete Composite Bridges
...Show More Authors

A novel demountable shear connector for precast steel-concrete composite bridges is presented. The connector uses high-strength steel bolts, which are fastened to the top flange of the steel beam with the aid of a special locking nut configuration that prevents bolts from slipping within their holes. Moreover, the connector promotes accelerated construction and overcomes the typical construction tolerance issues of precast structures. Most importantly, the connector allows bridge disassembly. Therefore, it can address different bridge deterioration scenarios with minimum disturbance to traffic flow including the following: (1) precast deck panels can be rapidly uplifted and replaced; (2) connectors can be rapidly removed and replaced; and (

... Show More
View Publication Preview PDF
Scopus (105)
Crossref (88)
Scopus Clarivate Crossref
Publication Date
Wed Mar 01 2023
Journal Name
Journal Of Engineering
Stiffness Characteristics of Pile Models for Cement Improving Sandy Soil by Low-Pressure Injection Laboratory Setup
...Show More Authors

Soil improvement has developed as a realistic solution for enhancing soil properties so that structures can be constructed to meet project engineering requirements due to the limited availability of construction land in urban centers. The jet grouting method for soil improvement is a novel geotechnical alternative for problematic soils for which conventional foundation designs cannot provide acceptable and lasting solutions. The paper's methodology was based on constructing pile models using a low-pressure injection laboratory setup built and made locally to simulate the operation of field equipment. The setup design was based on previous research that systematically conducted unconfined compression testing (U.C.Ts.). Th

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (2)
Scopus Crossref
Publication Date
Thu Oct 03 2024
Journal Name
Applied Organometallic Chemistry
Synthesis, Characterization, Molecular Docking, Cytotoxicity, and Antimicrobial Activity of Schiff Base Ligand and Its Metal Complexes
...Show More Authors
ABSTRACT<p>A Schiff base ligand (L) was synthesized via condensation of <italic>N</italic>‐(1‐naphthyl)ethylenediamine dihydrochloride with phthalaldehyde. The ligand was characterized by FT‐IR, UV–Vis, <sup>1</sup>H NMR, mass spectrometry, and elemental analysis (C, H, N). Five metal complexes (Co(II), Ni(II), Cu(II), Zn(II), and Cd(II)) were prepared with the ligand in a 1:1 (M:L) ratio using an aqueous ethanol solution. The complexes were characterized by FT‐IR, UV–Vis, mass spectrometry, and elemental analysis (C, H, N). Additionally, <sup>1</sup>H NMR spectroscopy was employed for Cd(II) complex. Antimicrobial activity of the ligand and its metal complexes against </p> ... Show More
View Publication
Scopus (24)
Crossref (17)
Scopus Clarivate Crossref