Preferred Language
Articles
/
alkej-197
Comparisons of Mechanical Properties of sub-mm Lead Based and Lead Free Based Solder Using in Manufacturing of Printed Circuits
...Show More Authors

Abstract

This study investigates the mechanical compression properties of tin-lead and lead-free alloy spherical balls, using more than 500 samples to identify statistical variability in the properties in each alloy. Isothermal aging was done to study and compare the aging effect on the microstructure and properties.

The results showed significant elastic and plastic anisotropy of tin phase in lead-free tin based solder and that was compared with simulation using a Crystal Plasticity Finite Element (CPEF) method that has the anisotropy of Sn installed. The results and experiments were in good agreement, indicating the range of values expected with anisotropic properties.

Keywords: Lead-free solder, composite solder, and aging.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Apr 01 2019
Journal Name
2019 4th Scientific International Conference Najaf (sicn)
Modeling and Experimental Research of Vibration N Properties of A Multi-Layer Printed Circuit Board
...Show More Authors

View Publication
Scopus (6)
Crossref (5)
Scopus Crossref
Publication Date
Sat Jan 01 2011
Journal Name
Journal Of Applied Sciences
Improvement of Mechanical Welding Properties by using Induced Harmonic Vibration
...Show More Authors

View Publication
Scopus (15)
Crossref (15)
Scopus Crossref
Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Engineering
Design of a PID-Lead Compensator for a Twin Rotor Aerodynamic System (TRAS)
...Show More Authors

This paper deals with a Twin Rotor Aerodynamic System (TRAS). It is a Multi-Input Multi-Output (MIMO) system with high crosscoupling between its two channels. It proposes a hybrid design procedure that combines frequency response and root locus approaches. The proposed controller is designated as PID-Lead Compensator (PIDLC); the PID controller was designed in previous work using frequency response design specifications, while the lead compensator is proposed in this paper and is designed using the root locus method. A general explicit formula for angle computations in any of the four quadrants is also given. The lead compensator is designed by shifting the dominant closed-loop poles slightly to the left in the s-plane. This has the effect

... Show More
Publication Date
Tue Mar 28 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Relationship between Blood Lead Levels and Hematological Parameters in Children from Al-Fallujah City in Iraq
...Show More Authors

Environmental exposures to lead remain a serious problem in the developing and industrializing countries. Children are the highest risk aged-group for lead poisoning. This study was designed to assess lead exposure in Al-Fallujah city by analyzing blood lead levels in children and adults and to explain the relationship between blood lead levels, hematological parameters and ferritin levels in the children. The study was performed on-(90) subjects, (65children and 25 adults).Venous blood samples were taken for estimation of hematological parameters, serum ferritin levels and blood lead levels. The children group was subdivided into four groups as: group (A) (low ferritin, low Hb), group (B) (low ferritin, normal Hb), group (C) (normal fer

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 01 2025
Journal Name
Iranian Journal Of Veterinary Medicine
Effect of Thymus Vulgaris on Hormonal Profile and Immunohistochemistry of Ovarian and Uterine Vascular Endothelial Growth Factor in Lead Acetate treated Rats
...Show More Authors

Background: Thymus vulgaris is a plant rich in essential oils acclaimed for the management of oxidative stress and inflammation in the organs. Meanwhile, the heavy metal lead is widely distributed in nature and continued exposure to lead acetate causes reduced fertility.Objectives: The present study aimed to investigate the effects of T. vulgaris on ovarian and uterine structural and functional characteristics in female rats exposed to lead acetate. Methods: Three groups of 18 mature Wistar albino female rats (Rattus norvegicus), 15 weeks old and weighing between 200 and 210 g, were established and handled for 60 days as follows: Group A (control group) received 0.5 mL of distilled water (DW) daily; group B received 5 mg/kg body weight (BW

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 19 2023
Journal Name
Journal Of Educational And Psychological Researches
Special Education Teachers’ Perceptions of the Factors lead to School Bullying of Students with Intellectual Disabilities in Asir
...Show More Authors

Abstract

This study aims to identify the most prominent factors that lead to bullying of students with intellectual disabilities in primary and middle schools from the perspectives of special education teachers. A quantitative descriptive approach was utilized. A questionnaire was used as a tool for data collection. The sample consisted of (72) male and female teachers from the Asir region in the Kingdom of Saudi Arabia. The results revealed the most prominent factors that lead to bullying as follows: factors associated with the school and its policies, factors associated with peers, factors associated with students with intellectual disabilities, and factors associated with general education teachers. The findin

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 20 2019
Journal Name
Baghdad Science Journal
Taxonomy of Memory Usage in Swarm Intelligence-Based Metaheuristics
...Show More Authors

Metaheuristics under the swarm intelligence (SI) class have proven to be efficient and have become popular methods for solving different optimization problems. Based on the usage of memory, metaheuristics can be classified into algorithms with memory and without memory (memory-less). The absence of memory in some metaheuristics will lead to the loss of the information gained in previous iterations. The metaheuristics tend to divert from promising areas of solutions search spaces which will lead to non-optimal solutions. This paper aims to review memory usage and its effect on the performance of the main SI-based metaheuristics. Investigation has been performed on SI metaheuristics, memory usage and memory-less metaheuristics, memory char

... Show More
View Publication Preview PDF
Crossref (3)
Clarivate Crossref
Publication Date
Mon Oct 03 2022
Journal Name
Physica Scripta
Radiation shielding properties of Cd-Bi-Pb-Zn-borate glasses: influence of Bi<sub>2</sub>O<sub>3</sub> activation
...Show More Authors
Abstract<p>We report the detail characterizations and <italic>γ</italic>-radiation protecting characteristics of some new types of cadmium (Cd)-bismuth (Bi)-lead (Pb)-zinc (Zn)-borate glasses of the form (70-x)B<sub>2</sub>O<sub>3</sub>-10ZnO-10PbO-10CdO-xBi<sub>2</sub>O<sub>3</sub> (with x = 0 to 20 mol%) synthesized via melt-quenching process. The influence of various Bi<sub>2</sub>O<sub>3</sub> contents on the <italic>γ</italic>-radiation shielding traits of the obtained glass samples was evaluated by exposing them at different <italic>γ</italic>-ray energies (0.356, 0.662, 1.173, and 1.33 MeV) whic</p> ... Show More
View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Sat Dec 01 2018
Journal Name
Nano Hybrids And Composites
Specific NH&lt;sub&gt;3&lt;/sub&gt; Gas Sensor Worked at Room Temperature Based on MWCNTs-OH Network
...Show More Authors

Functionalized Multi-Walled Carbon Nanotubes (MWCNTs-OH) network with thickness 4μm was made by the vacuum filtration from suspension (FFS) method. The morphology, structure and optical properties of the MWCNTs film were characterized by SEM and UV-Vis. spectra techniques. The SEM images reflected highly ordered network in the form of ropes or bundles with close-packing which looks like spaghetti. The absorbance spectrum revealed that the network has a good absorbance in the UV-Vis. region. The gas sensor system was used to test the MWCNT-OH network to detect NH3gas at room temperature. The resistance of the sensor was increased when exposed to the NH3gas. The sensitivities of the network w

... Show More
View Publication
Crossref (11)
Crossref
Publication Date
Sun Sep 21 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Salivary antioxidants in relation to dental caries among a group of lead-acid batteries factory workers
...Show More Authors

Background: Lead-acid battery workers are at higher risk for systemic diseases as well as oral diseases like dental caries. The aim of this study was to assess selected salivary antioxidants and their relation with dental caries among lead acid battery factory workers in comparison with non-exposed group. Materials and methods: The sample consisted of 35 subjects aged 35-45 year-old who worked in Babylon lead acid battery factory in Baghdad city and matching group that not exposed to lead were selected as a control. Dental caries severity was recorded by using DMFS index, stimulated salivary samples were collected and analyzed for the measurement of salivary antioxidants (uric acid, total protein, catalase and glutathione peroxidase enzymes

... Show More
View Publication Preview PDF