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
Tue Jun 01 2004
Journal Name
كلية اللغات
خيبة آمال غرامية/ مشروع الدبلوم العالي في الترجمة- قسم اللغة الاسبانية- كلية اللغات- جامعة بغداد
...Show More Authors

Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Educational And Psychological Researches
تقويم محتوى كتاب الاحياء للصف السادس العلمي من وجهة نظرمدرسي ومدرسات الاحياء في محافظة كركوك
...Show More Authors

The present study aims to identify the extent to which biology book of sixth grade achieves the basic scientific aspects in light of its scientific objectives. To achieve this goal, the researcher needed to build two questionnaires to evaluate the biology book for sixth-grade. To answer the questions of the study, the researcher used the following statistical methods : the weighted average, and percentages; and to identify the extent to match the perspective of teachers of the material with the perspective of a researcher in each paragraph of the questionnaire as well as the degree of severity of each paragraph in the book neighborhoods sixth-grade has reached Aalbagesh to several of the most important results: 1. All the teachers were w

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
التعايش السلمي في الاسلام بين التنظير والتطبيق عهد الامام علي (عليه السلام) للاشتر النخعي / انموذجا
...Show More Authors

     Peaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established

View Publication Preview PDF
Publication Date
Sat Nov 10 2018
Journal Name
Journal Of Planner And Development
(دور الوعي البيئي لدى الأسرة العراقية في التخلص من النفايات الصلبة) (مدينة الرمادي – حي العزيزية)
...Show More Authors

View Publication Preview PDF
Publication Date
Fri Nov 15 2024
Journal Name
الاستاذ
اثر انموذج التعلم الخبراتي ل روبين في مادة الفيزياء والدافعية الابداعية لطلاب الصف الرابع العلمي
...Show More Authors

الملخص : يهذف البحث التعرف على اثر آنموذج التعلم الخبراتي (لروبين) في مادة الفيزياء والدافعية الإبداعية لدى طلاب المرطة الإعدادية, وذلك بالتحقق من الفرضية الآتية: • لا يوجد فروق ذات دلالة إحصائية عند مستوى (0.05) بین متوسط درجات المجموعة التجريبية التـي درست وفق إستراتيجية التعلم الخبراتي (لروبين) ومتوسط درجات المجموعة الضابطة التي درست وفق الطريقة الاعتيادية في مقیاس الدافعية الابداعية. استخدم الباحثون التص

... Show More
Publication Date
Mon Dec 25 2017
Journal Name
Al-khwarizmi Engineering Journal
Removal Water Turbidity by Crumb Rubber Media
...Show More Authors

Abstract

The removal of water turbidity by using crumb rubber filter was investigated .The present study was conducted to evaluate the effect of variation of influent water turbidity (10, 25 and 50 NTU), media size (0.6and 1.14mm), filtration rate (25, 45 and 65 l/hr) and bed depth (30 and 60 cm) on the performance of mono crumb rubber filter in response to the effluent filtered water turbidity and head loss development, and compare it with that of conventional sand filter.Results revealed that 25 l/hr flow rate and 25 NTU influent turbidity were the best operating conditions.  smaller media size and higher bed depth gave the best removal efficiency while higher media size and small bed depth gave lower head

... Show More
View Publication Preview PDF
Publication Date
Sun Oct 21 2018
Journal Name
Iraqi Journal Of Physics
Spectroscopic study the plasma parameters for Pb doped CuO prepared by pulse Nd:YAG laser deposition
...Show More Authors

In this work, plasma parameters such as, the electron temperature )Te(, electron density ne, plasma frequency )fp(, Debye length )λD(
and Debye number )ND), have been studied using optical emission spectroscopy technique. The spectrum of plasma with different values of energy, Pb doped CuO at different percentage (X=0.6, 0.7, 0.8) were recorded. The spectroscopic study for these mixing under vacuum with pressure down to P=2.5×10-2 mbar. The results of electron temperature for X=0.6 range (1.072-1.166) eV, for X=0.7 the Te range (1.024-0.855) eV and X=0.8 the Te is (1.033-0.921) eV. Optical properties of CuO:Pb thin films were determined through the optical transmission method using ultraviolet visible spectrophotometer within the ra

... Show More
View Publication Preview PDF
Crossref (8)
Crossref
Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
تأثير تدفق القروض الخارجية في تحقيق التحولات الهيكلية لاقتصادات بعض دول الاسكوا للمدة (1990 ـ 2002)
...Show More Authors

تتطلب عملية التنمية الاقتصـادية في الدول النامية مبالغ كبيرة من رؤوس الأمـوال اللازمة لتنفيذ البرامج والخطط الاقتصادية، ولما كانت الاسـتثمارات التي تنفذها هذه الدول خلال حقبة معينة، تزيد على ما تم  تحقيقه من موارد مالية محلية، فلابد أنْ يمول الفرق من خلال انسياب صافٍ لرأس المال الأجنبي (قروض ومساعدات) إلى الداخل خلال المدة نفسها، لغـرض سَدّ الفجوة في المـوارد المحلية المعدة للاسـتثمار، وعانت بعض د

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Nov 11 2018
Journal Name
Arab Science Heritage Journal
تدهور تدهور التجارة وانخفاض عائدات الضرائب في ايران(1) خلال عهد الشاه سلطان حسين ( 1694-1722).
...Show More Authors

The weakness of the central rule at the reign of Shah Sultan Hussain who is regarded as the last Shah who governed the Safawi state near to its falling at the hold of Afghan in 1722 which is the main and the real factor for the economic collapse. The tribes of trade have faced stealing and robbery actions which have been compressed to a very big extent. This action was not the responsibility of Shah alone,

View Publication Preview PDF
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
أستخدام الضريبة البيئية للحد من الملوثات الناجمة عن عوادم السيارات: أنموذج مقترح للضريبة البيئية في العراق
...Show More Authors

 The researcher tried to show the importance of using environmental taxes as an effective economic factor for reducing contaminators resulting from cars exhausts, and presenting a suggested pattern for  environmental taxes as a nucleus and a starting point for a wider implementing of environmental taxes in Iraq.                                                                      &nbs

... Show More
View Publication Preview PDF