Background: Incorporation of chemical additives has long been a technique used to improve properties of the gypsum products. The purpose of this work was to study the effects of adding a combination of gum Arabic and calcium hydroxide to a type III dental stone and type IV improved die stone with different proportion. The effect on water/powder ratio, and surface hardness was determined. Material and method: Both material stone and die stone were blended with two proportion of additives so that each material was mixed twice but with different proportion of gum Arabic (0.1% and 0.2%) and calcium hydroxide (0.5 % and 0.3%). Data for hardness were subjected to two-way analysis of variance. Results: The results revealed that the chemical additi

Abstract

In the field of construction materials the glass reinforced mortar and Styrene Butadiene mortar are modern composite materials. This study experimentally investigated the effect of addition of randomly dispersed glass fibers and layered glass fibers on density and compressive strength of mortar with and without the presence of Styrene Butadiene Rubber (SBR). Mixtures of 1:2 cement/sand ratio and 0.5 water/cement ratio were prepared for making mortar. The glass fibers were added by two manners, layers and random with weight percentages of (0.54, 0.76, 1.1 and 1.42). The specimens were divided into two series: glass-fiber reinforced mortar without SBR and glass-fiber reinforced mortar with 7% SBR of mixture water. All s

Abstract :

This research aims to examine the correlation and the impact of Strategic leadership on Achieving Organizational in some of establishments in ministry of construction and housing which is under public founds, Starting from the importance of research in public organizations and the importance of these organizations to the community, it is rely descriptive analytical methods in achievement of this research, the research involved board of directors, Data has collected from (92) respondents, represent the respondent society exclusively and comprehensively, it involved the general directors, assistant general directors and heads of department, The research relied programs (Excel 2010, Spss V.21), moreover, some o

Urbanization can not be seen as a modern phenomenon. It has led people to live and live in cities for thousands of years. It should be noted here that the oldest villages and large cities have emerged after the crystallization of civilization, that the emergence of cities was one of the phenomena of civilization. There is no doubt that the cities after the emergence has contributed to the development of civilization effective contribution. There has been a civilizational progress when the man practiced agriculture and used metal tools and invented the wheels and went to write in the New Stone Age. In this period, many changes in the field have taken place in economic, cultural and social life. In the economic and cultural aspect, this tr

The nuclear level density parameter  in non Equi-Spacing Model (NON-ESM), Equi-Spacing Model (ESM) and the Backshifted Energy Dependent Fermi Gas model (BSEDFG) was determined for 106 nuclei; the results are tabulated and compared with the experimental works. It was found that there are no recognizable differences between our results and the experimental -values. The calculated level density parameters have been used in computing the state density as a function of the excitation energies for ⁵⁸Fe and ²⁴⁶Cm nuclei. The results are in a good agreement with the experimental results from earlier published work.

Receipt date:12/15/2020   accepted date:12/29/2020  Publication date: 12/31/2021

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The study aims to review the division between Fateh and Hamas between 2006 -2007 based primarily on the documents and statements that have been announced in various media, through a review of the course of events after the Palestinian elections of 2006, which resulted in the victory of Hamas, indicating the course division, and the position of each of

Changing the Wine into Vinegar