The formulations and the properties of the Zinc Polycarboxylate Dental Cements are reviewed then new cements of this type are prepared with modified solid part of the cement. High silica glass powder with different particle sizes is prepared and added with different weight percentages to the zinc oxide. The liquid part of the prepared cements was merely 44% concentration of the polyacrylic acid. Accordingly, the usual and expensive additives to the liquid and solid part of the cement are eliminated. The working and setting times, compressive strength, flexural strength and modulus are measured according to ADA specifications. The formulated cement has long working times without much lengthening of the setting times. In addit

In this study, the kinetics for the reaction of tert-butanol esterification with acetic acid in the presence of Dowex 50Wx8 catalyst was investigated. The reaction kinetic experiments were conducted in 1000 milliliter vessel at temperatures ranged from 50 - 80 oC, catalyst loading 25-50 g/L, and the molar ratios of acetic acid to tert-butanol from 1/3 – 3/1. The reaction rate was found to increase with increasing temperature and catalyst loading. It was also found the conversion of the tert-butanol increases as the molar ratio of acid to alcohol increases from 1/3 – 3/1. The Non-ideality of the liquid phase was taken into account by using activities instead of molar fractions. The activity coefficients were calculated according to th

The research aims at:

1. Identifying the problems facing kindergarten teachers.
2. Identifying the nature of the problems facing kindergarten teachers.

To achieve the aim of the research, the researcher prepared a questionnaire to identify the problems that face the teachers of kindergartens. The questionnaire was subjected to the consultation of a group of specialized expertise in the educational and psychological sciences to certify the propriety of the items of the questionnaire and it gained a rate of (80%), and the stability of the scale gained (0.91) and it stands for a correlation parameter with a statistical significance and it was calculated by using Person’s R Corre

Data compression offers an attractive approach to reducing communication costs using available bandwidth effectively. It makes sense to pursue research on developing algorithms that can most effectively use available network. It is also important to consider the security aspect of the data being transmitted is vulnerable to attacks. The basic aim of this work is to develop a module for combining the operation of compression and encryption on the same set of data to perform these two operations simultaneously. This is achieved through embedding encryption into compression algorithms since both cryptographic ciphers and entropy coders bear certain resemblance in the sense of secrecy. First in the secure compression module, the given text is p

<span>Deepfakes have become possible using artificial intelligence techniques, replacing one person’s face with another person’s face (primarily a public figure), making the latter do or say things he would not have done. Therefore, contributing to a solution for video credibility has become a critical goal that we will address in this paper. Our work exploits the visible artifacts (blur inconsistencies) which are generated by the manipulation process. We analyze focus quality and its ability to detect these artifacts. Focus measure operators in this paper include image Laplacian and image gradient groups, which are very fast to compute and do not need a large dataset for training. The results showed that i) the Laplacian

Background: A major difference between the treatment of the skin lesions and the odontogenic and non-odontogenic sinuses. We aimed to analyze a substantial number of consecutive causes in order to clinical suspicion in the differential diagnoses may be correctly weighted. Materials and methods: The material of this research consisted of 40 patients. A complete history is collected from the patients with the duration and the site of the sinus present, the patient was examined for factors of the fistulas and sinuses and its associations, and patient having any concomitant lesions, a medical consultation done for opinion and management. Clinical examination with facial fistulas and sinuses was mandatory to avoid any mistakes that may occur. A

This study presents a comprehensive list of the freshwater and marine bivalves distributed in Iraq. A total of 51 species were recorded, and distributed as: 14 freshwater species, and 37 marine species, these species belonging to 25 families, all available remarks on the distribution, taxonomy, and nomenclature of these species were given. This study included the recently collected specimens along with those previously studied and recorded in Iraq.