Back ground: Glass ionomer materials lack resistance to wear and pressure and are susceptible to moisture during the initial stages of setting and dehydration. So this study was done to assess diametral tensile strength and microhardness of glass ionomer reinforced by different amounts of hydroxyapatite. Materials and methods: In this study a hydroxyapatite material was added to glass monomer cement at different ratios: 10%, 15%, 20%, 25% and 30% (by weight). The diametral tensile strength test described by the British standard specification for zinc polycarboxylate cement was used in this study and the microhardness test was performed using Vickers microhardness testing machine and the microhardness values were calculated and statistical comparison was performed on the tested groups. Results: The group of glass ionomer cement that contains 20% hydroxyapatite has higher diametral tensile strength and microhardness values than other groups of this study. Also the results showed that the group of glass ionomer cement without hydroxyapatite has the lowest values of diametral tensile strength and microhardness than other groups. The groups of glass ionomer cement with 10%, 15%, 25% and 30% hydroxyapatites also showed increasing in diametral tensile strength and microhardness values in comparison with group of glass ionomer cement without hydroxyapatite. Conclusion: The addition of hydroxyapatite to conventional glass ionomer cement will increase its diametral tensile strength and microhardness
Purpose Heavy metals are toxic pollutants released into the environment as a result of different industrial activities. Biosorption of heavy metals from aqueous solutions is a new technology for the treatment of industrial wastewater. The aim of the present research is to highlight the basic biosorption theory to heavy metal removal. Materials and methods Heterogeneous cultures mostly dried anaerobic bacteria, yeast (fungi), and protozoa were used as low-cost material to remove metallic cations Pb(II), Cr(III), and Cd(II) from synthetic wastewater. Competitive biosorption of these metals was studied. Results The main biosorption mechanisms were complexation and physical adsorption onto natural active functional groups. It is observed that
... Show MoreWith the increasing rate of unauthorized access and attacks, security of confidential data is of utmost importance. While Cryptography only encrypts the data, but as the communication takes place in presence of third parties, so the encrypted text can be decrypted and can easily be destroyed. Steganography, on the other hand, hides the confidential data in some cover source such that the existence of the data is also hidden which do not arouse suspicion regarding the communication taking place between two parties. This paper presents to provide the transfer of secret data embedded into master file (cover-image) to obtain new image (stego-image), which is practically indistinguishable from the original image, so that other than the indeed us
... Show MoreThe poetic text, being an artistic product, is achieved during the moment of inspiration. However, this inspiration does not come from a vacuum. Rather, it needs a good environment capable of pushing the poetic text to the surface after its formation in the poet's mind, with the images and ideas it contains, expressed in his own language and style. Distinguished, and we must not overlook that language is not just words and meanings, but rather those feelings and emotions that are the essence of creativity (()), including musical, sentimental and imaginative aspects with colors of suggestion and symbols (()), because the poetic language is distinguished from others in that it (Symbols for psychological states are the substance of thought)
... Show MoreAudio-visual detection and recognition system is thought to become the most promising methods for many applications includes surveillance, speech recognition, eavesdropping devices, intelligence operations, etc. In the recent field of human recognition, the majority of the research be- coming performed presently is focused on the reidentification of various body images taken by several cameras or its focuses on recognized audio-only. However, in some cases these traditional methods can- not be useful when used alone such as in indoor surveillance systems, that are installed close to the ceiling and capture images right from above in a downwards direction and in some cases people don't look straight the cameras or it cannot be added in some
... Show MoreThis paper highlights the main features of conjunctive adverbials and their occurrence in English academic prose. It accounts for the semantic roles of conjunctive adverbials, forms in which they are used, their positions within a sentence, and their frequency of occurrence in different registers with special reference to academic prose. It also tries to investigate possible differences in men's and women's use of conjunctive adverbials.
Keyword: conjunctive adverbials, linking adverbials, stance adverbials, circumstance adverbials, academic prose
Radiation measuring devices need to periodic calibration process to examine their sensitivity and the extent of the response. This study is used to evaluate the radiation doses of the workers in the laboratories of the Directorate of Safety as a result of the use of point sources in calibrating of the devices in two ways, the first is the direct measurement by the FAG device and the others using RESRAD and RAD PRO programs. The total doses values using FAG were (2.57 μSv/y, 102.3 μSv/y and 20.75 μSv/y for TLD laboratory, Gamma spectroscopy analyses (GSA) laboratory and equipment store respectively, and the total doses that calculated using RESRAD and RAD PRO were 1.518 μSv/y, 76.65 μSv/y and 21.2 μSv/y for the above laboratories. t
... Show MorePortable and stationary electrical generators became quite popular in Iraq soon after the shortage in national electrical
energy after 2003. Multi step risk assessment process is used in this study in the assessment of risks caused by
contamination of indoor air by lead particles emitted from domestic electrical generators. Two portable electrical
generators are tested under controlled indoor conditions (Radial LG (0.9 keV) fueled with benzene and oil and TigMax
(3 keV), fueled with benzene only). Lead particles in air were sampled by using portable dust sampler (Sniffer, L-30).
The atmospheric particulate sampling process is carried out in a flat located in the first floor of a three stories building
located in Baghdad
Objectives: To assess pregnant women’s knowledge regarding syphilisand to find out the relationship between women’s knowledge regarding syphilis infection and demographic and reproductive variables. Methodology: A descriptive analytical study of non probable (purposive sample) of 250 pregnant women during their different gestational ages for the period (October 2nd to April 25th 2013) by using questionnaire format consists of demographic variables and items of women's knowledge regarding syphilis who are visiting primary health care centers in Al-Kharkh and Al-Rrusafa in Baghdad city. The coefficient relia