Background: Color stability of glass ionomers (GIs) could be affected by many factors such as pH and consumption of liquid medications like antibiotics. Most common antibiotics used during childhood are amoxicillin suspension (AM.S) and azithromycin suspension (AZ.S) which have acidic and basic pH respectively. Aim: to evaluate and compare the effect of AM.S and AZ.S on color stability of nano resin-modified GI. Methods: Thirty disc of nano resin-modified glass ionomer (2mm height x 4mm diameter) were divided into three groups (n=10 for each) and independently exposed to AM.S, AZ.S, and artificial saliva (A.S.). Color stability was evaluated in triplicate by VITA Easyshade® before and after three immersion protocols, repeated over a three-week duration with two-days intervals. In each protocol, samples were exposed for two minutes, three times daily for AM.S, once daily for AZ.S, and A.S. full day. GI discs rinsed off after each immersion and kept in artificial saliva until next immersion period. Results: One way ANOVA test and Post-hoc analysis of the changes in color space compartments of nano-resin modified GI samples demonstrated just a significant change (p˂0.05) in yellow-blue axis (Δb*) value after immersion in AM.S in comparison with A.S. Total Color change values (ΔE) of nano resin-modified glass ionomer samples also illustrated a significant effect (p˂0.05) between AM.S and A.S. only. The highest (ΔE) value was recorded for samples immersed in AM.S (ΔE =12.5) followed by AZ.S (ΔE=6.5) while the lowest was recorded for A.S. (ΔE=1.1). Conclusion: AM.S (the acidic medication) exhibited a higher staining effect to nano-resin modified GI samples when compared with AZ.S (the basic medication). Several factors such as low pH, more exposure time and coloring material of the immersion media added critical roles in coloring instability.
The reduction of vibration properties for composite material (woven roving E-glass fiber plies in thermosetting polyester matrix) is investigated at the prediction time under varied combined temperatures (60 to -15) using three types of boundary conditions like (CFCF, CCCF, and CFCC). The vibration properties are the amplitude, natural frequency, dynamic elastic moduli (young modulus in x, y directions and shear modulus in 1, 2 plane) and damping factor. The natural frequency of a system is a function of its elastic properties, dimensions, and mass. The woven roving glass fiber has been especially engineered for polymer reinforcement; but the unsaturated thermosetting polyester is widely used, offering a good balance of vibration p
... Show MoreWater sorption (WS) and solubility (S) of the experimental flowable composites (EFCs), made from silica filler of rice husk are important to explore the reaction of EFCs against different oral environments. To investigate the effects of different camphorquinone concentrations on the WS and S of the EFCs. EFCs were fabricated from nanohybrid silica and involved different weights of camphorquinone (CQ) (0.03 g, 0.05 g and 0.075 g) and other materials. 3 groups of 7 disk-like samples of each of the three EFCs and Revolution Formula 2 (RF2) were tested. Before immersion, the volumes were recorded and the mass of each sample was recorded, as m1. During the immersion phase in three different media for 7 days, the weight was recorded as m2. During
... Show Moreobjective the research to diagnosis and interpretation of the nature of the effect between the basic elements of knowledge management (tecgnology , structure , culture , process , human resource ) and the strategic performance of the Iraqi private banks, the research community and the level dimensions, and I've tested this research in the private banking sector represented by (7), especially in Baghdad, Iraqi banks, and applied research on sample consisting of 100 distributors in several administrative levels Director (Director, Director of the department, branch manager), and use the researcher questionnaire Head to collect data and information tool, and some private banks annual reports, has sought research to test
... Show MoreA simple low-cost approach at various exposure times was utilized to generate cold plasma in the aim to fabricate AuNPs. UV-Visible spectra and X-ray diffraction were used to characterize the nanoparticles (XRD). Surface Plasmon resonance was observed in the synthesized AuNPs at 530, 540, and 533 nm. For all samples, the patterns of XRD show very intensive peaks implying the fcc crystalline structure of AuNPs. The average crystallite size of AuNPs is ranging between 20-30 nm. The observation of morphology by FESEM revealed the spherical formation of AuNPs. Doses of 100 and 200 ppm of AuNPs were adapted to investigate their effect on the blood-mixture with and without a 20-second of cold plasma exposure. The WBC components in the blood
... Show MoreThe present research was conducted to synthesis Y-Zeolite by sol-gel technique using MWCNT (multiwalled carbon nanotubes) as crystallization medium to get a narrow range of particle size distribution with small average size compared with ordinary methods. The phase pattern, chemical structure, particle size, and surface area were detected by XRD, FTIR, BET and AFM, respectively. Results shown that the average size of Zeolite with and without using MWCNT were (92.39) nm and (55.17) nm respectively .Particle size range reduced from (150-55) nm to (130-30) nm. The surface area enhanced to be (558) m2/g with slightly large pore volume (0.231) km3/g was obtained. Meanwhile, degree of crystallization decrease
... Show MoreThe present research was conducted to synthesis Y-Zeolite by sol-gel technique using MWCNT (multiwalled carbon nanotubes) as crystallization medium to get a narrow range of particle size distribution with small average size compared with ordinary methods. The phase pattern, chemical structure, particle size, and surface area were detected by XRD, FTIR, BET and AFM, respectively. Results shown that the average size of Zeolite with and without using MWCNT were (92.39) nm and (55.17) nm respectively .Particle size range reduced from (150-55) nm to (130-30) nm. The surface area enhanced to be (558) m2/g with slightly large pore volume (0.231) km3/g was obtained. Meanwhile, degree of crystallization decreased to 120%.
Bromocriptine mesylate is a semisynthetic ergot alkaloid derivative with potent dopaminergic activity, used in the treatment of pituitary tumors, Parkinson's disease (PD), hyperprolactinaemia, neuroleptic malignant syndrome, and type 2 diabetes ,the oral bioavailability is approximately 6%, therefore aim its prepare and evaluate bromocriptine mesylate as liquid self nano emulsifying drug delivery system to enhance its solubility , dissolution and stability . Solubility study was made in different vehicles to select the best excipients for dissolving bromocriptine mesylate. Pseudo-ternary phase diagrams were constructed at 1:1, 2:1, 3:1 and 4:1 ratios of surfactant and co-surfactant, four formulations were pre
... Show MoreIn a connected graph , the distance function between each pair of two vertices from a set vertex is the shortest distance between them and the vertex degree denoted by is the number of edges which are incident to the vertex The Schultz and modified Schultz polynomials of are have defined as:
respectively, where the summations are taken over all unordered pairs of distinct vertices in and is the distance between and in The general forms of Schultz and modified Schultz polynomials shall be found and indices of the edge – identification chain and ring – square graphs in the present work.
Epoxy (EP) – Silica (SiO2) composites are well known composites used in microelectronic industry . So it is important to study their dielectric behavior under different conditions such as
the presence carbon black (UV absorber) and immersion in the water for 30 days .
Dielectric properties were calculated over the frequency range 102 – 106 Hz for epoxy composites with different weight % of micrometer 1.5μm SiO2 particles (60%, 65% and 70wt%) modified with 0.5wt% silane coupling agent to improve adhesion between EP and SiO2 phases .