ABSTRACT Background: Improving the properties of heat- cured and self-cured acrylic resin have been studied by many researchers. However, little studies concerned with visible light cured resin (VLCR) improved through addition of nanofiller are available. The purpose of this study was to evaluate some properties of (VLCR) after addition of SiO2 nanofiller. Materials and Methods: SiO2 nanofiller were added to (VLCR) tray material after being dissolved in tetrahydrofuran (THF) solvent. According to the pilot study 2% SiO2 nanofiller addition exhibited better properties than the other percentages (1%, 3%). The main study conducted involved (100) specimens divided into 5 groups according to the test included. (20) Specimens were selected for each test (10 samples for the control group and 10 samples for the experimental 2% SiO2 nanofiller group). The properties investigated were transverse strength, impact strength, surface hardness, surface roughness, water sorption and solubility. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to assess nanofiller distribution and identification of elements. The data were subjected to descriptive statistical analysis and independent sample t-test. Results: The mean value of transverse strength of experimental group increased significantly, while the impact strength of experimental group decreased significantly when compared to control group. A significant increase in surface hardness was noticed in the experimental group, while non-significant increase in surface roughness was observed. The water sorption values were decreased significantly, while a non-significant decrease in water solubility was observed in the experimental group. Conclusion: Addition of SiO2 nanofiller to (VLCR), slightly improve the transverse strength and surface hardness, while water sorption and solubility slightly decreased. The impact strength was significantly deteriorated, while the surface roughness shows non-significant increment.
In the coming decade, a substantial rise in energy consumption within the buildings sector is predicted to lead to a 30% increase in greenhouse gas emissions. The choice of materials for building envelopes significantly influences the overall energy demand of HVAC systems, which contribute significantly to electricity usage. To enhance compatibility between grey clay and straw, a suggested approach involves using a composite material comprising rice water and grey clay, enriched with a high proportion of rice straw and soaked in rice water. This environmentally friendly technique yields a green construction material capable of reducing energy consumption in HVAC systems by up to 35.6% over a 24-h period. The potential energy savings of this
... Show MoreAbstract: Mixed ligand Mn(II), Co(II), Ni(II), Cu (II), Zn(II), and Cd(II) complexes with (TMAP) Schiff base ligand and (8HQ) have been composition and analyzed. Diagnosis by, melting point, solubility, Electronic, mass and IR-spectroscopic studies, conductivity elemental, thermoanalytical analysis displayed the forming of mononuclear complexes. Spectral studies results suggest an octahedral system or the metal (II) mixed complexes. The detainments of molar conductance of the mixed complexes in DMF coincide to electrolytic nature of the mixed complexes, consequently, these complexes could be subedited as [M(TMAP)(8Q)(H2O)]nX.yH2O (M=Co(II) and Cu(II) complexes(where n = 1, y = 0 ); [M(TMAP)(8Q)(H2O)]nX.yH2O (M = (where n = 1, y = 1 for Ni(
... Show MoreThe chromatographic behaviour of liquid crystalline compounds benzylidene-p-aminobenzoic acid and 4-(p-methyl benzylidene)-p-aminobenzoic acid as stationary phases for the separation of dimethylphenol isomers was investigated. These isomers were analysed on benzylidene-p-aminobenzoic acid within a nematic range of 169-194 ◦C with a temperature interval of 5 ◦C. Better peak resolution was at a column temperature of 190 ◦C. The analysis was repeated on a 4-(p-methyl benzylidene)-p-aminobenzoic acid column at a nematic temperature of 256 ◦C, which represented the end of the nematic range, and gave the optimum peak resolution. It was found that isomer better separation was obtained at 20% loading for both liquid crystal materials. Other
... Show MoreA sense of safety is the first requirement for human stability in a place such as a home. Many local studies investigated Baghdadi houses and their architectural changes, but the relationship between safety and sustainability in Baghdadi houses has not been studied, so the research problem was: What are the architectural elements that relate to the concept of a safe house as a home in Baghdad as a case study? How is it related to the sustainability?
The research aims to identify the architectural elements of the safe house in Baghdad, to work on these elements by architects to enhance the sustainability of the residential environment, and create homes t
When embankment is constructed on very soft soil, special construction methods are adopted. One of the techniques is a piled embankment. Piled (stone columns) embankments provide an economic and effective solution to the problem of constructing embankments over soft soils. This method can reduce settlements, construction time and cost. Stone columns provide an effective improvement method for soft soils under light structures such as rail or road embankments. The present work investigates the behavior of the embankment models resting on soft soil reinforced with stone columns. Model tests were performed with different spacing distances between stone columns and two lengths to diameter ratios of the stone columns, in addition to different
... Show MoreThis work aims to introduce the concepts of left and right derivations in an AT-algebra and discuss some interesting theorems of these concepts. Also, a fuzzy derivation of an AT-subalgebra, a fuzzy right (left) derivation ideal, a fuzzy derivation of AT-subalgebra, and a fuzzy right (left) derivation ideal are studied. Finally, a level derivation of AT-algebras is defined and some propositions are achieved.
Electrocardiogram (ECG) is an important physiological signal for cardiac disease diagnosis. With the increasing use of modern electrocardiogram monitoring devices that generate vast amount of data requiring huge storage capacity. In order to decrease storage costs or make ECG signals suitable and ready for transmission through common communication channels, the ECG data
volume must be reduced. So an effective data compression method is required. This paper presents an efficient technique for the compression of ECG signals. In this technique, different transforms have been used to compress the ECG signals. At first, a 1-D ECG data was segmented and aligned to a 2-D data array, then 2-D mixed transform was implemented to compress the
The rise of online platforms has transformed the discourse landscape, enabling users to create and share content actively, thereby shaping public perceptions and societal narratives. Understanding the dynamics of this discourse is essential for comprehending its socio-political implications. This review aims to provide a comprehensive overview of Critical Discourse Analysis (CDA) concerning online platforms, exploring how language is utilized across various digital contexts to influence identity formation and social inequalities. Methodologically, the review systematically searches electronic databases, including Google Scholar and ProQuest, using keywords related to CDA and online platforms. A total of 30 relevant studies are purpo
... Show MoreThe main objective of this study is to get a secure broadcasting in real time applications for audio files (precisely the Wave type) and to increase the degree of complexity of the encrypt/decrypt arithmetic operations in the finite . field GF(28) on these files. This objective can be achieved by implementing different proposed architectures, methods and algorithms both in block and stream cipher structure to increase the degree of complexity. For high utilization of resources and fast execution time of operations in cryptographic processes in the proposed cryptographic algorithms, the parallel computing was implemented by using OpenMP directives. The AES Rijndael algorithm has been considered as a base for the developed algorithms in the b
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