Background: elastomeric impression materials are indicated when a high degree of accuracy is required, due to their excellent properties like details reproduction, dimensional stability and tear strength but with main two disadvantages those are their hydrophilicity as well as the absence of antibacterial activity. This study aimed to evaluate the effect of incorporation of 0.5% wt Ag-Zn zeolite into condensation silicone through the following tests; setting time, dimensional stability, reproduction of details, wettability, and hardness . Materials and methods: one hundred specimens were constructed of condensation silicone, divided into two groups for the first 50 specimens one0.5% by wt Ag -Zn zeolite was added, keeping the other fifty specimens without addition. Then each group further subdivided into five subgroups according to the conducted test. The tests performed were; setting time, dimensional stability, reproduction of details, hardness and wettability. Results: A statistically non-significant effect on the setting time and reproduction of details tests was observed, combined with a highly significant increase of wettability of condensation silicone after incorporation of 0.5% wt Ag-Zn zeolite with non-significant increase of dimensional change of condensation silicone following incorporation of 0.5% wt Ag-Zn zeolite. Hardness test results shoed statistically significant increase following the addition of Ag-Zn zeolite. Conclusion: Ag-Zn zeolite incorporated into condensation silicone, improved wettability which determine the extent to which an impression material replicates the structures of the oral cavity and production of bubble-free gypsum die. It also showed a statistically significant increase in the hardness of condensation silicone impression material, and had no effect on setting time, reproduction of details and dimensional stability.
Two types of monofloral Malaysian honey (Gelam and Nenas) were analyzed to determine their antioxidant activities and total phenolic and flavonoid contents, with and without gamma irradiation. Our results showed that both types of honey can scavenge free radicals and exhibit high antioxidant-reducing power; however, Gelam honey exhibited higher antioxidant activity (p < 0.05) than Nenas honey, which is in good correlation (r = 0.9899) with its phenolic contents. Interestingly, we also noted that both irradiated honeys have higher antioxidant activities and total phenolic and flavonoid contents compared to nonirradiated honeys by Folin-Ciocalteu and UV-spectrophotometry methods, respectively. However, HPLC analysis for phenolic co
... Show MoreThe corrosion inhibition effect of a new furan derivative (furan-2-ylmethyl sulfanyl acetic acid furan-2-ylmethylenehydrazide) on mild steel in 1.0 M HCl was investigated using corrosion potential (ECORR) and potentiodynamic polarization. The obtained results indicated that the new furan derivative (furan-2-ylmethyl sulfanyl acetic acid furan-2-ylmethylenehydrazide) (FSFD) has a promising inhibitive effects on the corrosion of mild steel in 1.0 M HCl across all of the conditions examined. The density functional theory (DFT) study was performed on the new furan derivative (FSFD) at the B3LYP/6-311G (d, p) basis set level to explore the relation between their inhibition efficiency and molecular electro
The comparative study tries to find the common points in two different authors’ works and in this kind of studying so many other common but the hidden points may be revealed. Postwar literature is somehow one of the best literary genres for finding the common factors and features that the poets have tried to present in their works elements such as desire to be winner, cruelty, inhumanity, and absurdity of the war. The Iranian poet late Qaisar Aminpour(1961-2007) and Yusef Komunyakaa ( 1947) from Bogalusa, Louisiana, are among the great American and Iranian poets whose works so many times have been interpreted and analyzed. The finding the outstanding and the most important points and themes in the postwar poems of these
... Show MoreThe effect of applied current on protection of carbon steel in 0.1N NaCl solution (pH=7) was investigated under flow conditions (0-0.262 m/s) for a range of temperatures (35-55°C) using rotating cylinder electrode. Various values of currents were applied to protect steel from corrosion, these were Iapp.=Icorr., Iapp.=2Icorr. and Iapp.=2.4Icorr. under stationary and flow conditions. Corrosion current was measured by weight loss method. The variation of protection potential with time and rotation velocity at various applied currents was assessed. It is found that the corrosion rate of carbon steel increases with rotation velocity and
has unstable trend with temperature. The protection current required varies with temperature and it inc
The distribution of chilled water flow rate in terminal unit is an important factor used to evaluate the performance of central air conditioning unit. A prototype of A/C unit has been made, which contains three terminal units with a complete set of accessories (3-way valve, 2-way valve, and sensors) to study the effect of the main parameters, such as total water flow rate and chilled water supply temperature with variable valve opening. In this work, 40 tests were carried out. These tests were in two groups, 20 test for 3-way valve case and 20 test for 2-way valve case. These tests were performed at three levels of valve opening, total water flow rate and water supply temperature according to the design matrices establis
... Show MoreThe importance of the present work falls on the pitting corrosion behavior investigation of 304 SS and 316 SS alloys in 3.5 wt% of aqueous solution bearing with chloride and bromide anion at different solutions temperature range starting from (20-50)oC due to the pitting corrosion tremendous effect on the economic, safety and materials loss due to leakage. The impact of solution temperatures on the pitting corrosion resistance at 3.5wt% (NaCl and NaBr) solutions for the 304 SS and 316 SS has been investigated utilizing the cyclic polarization techniques at the potential range -400 to1000 mV vs. SCE at 40 mV/sec scan rate followed by the surface characterization employing Scanning Electron&nbs
... Show MoreMefenamic acid (MA) is one of the non-steroidal anti-inflammatory drugs, it is widely used probably due to having both anti-inflammatory and analgesic activity, the main side effects of mefenamic acid include gastrointestinal tract (GIT) disturbance mainly diarrhea, peptic ulceration, and gastric bleeding. The analgesic effects of NSAIDs are probably linked to COX-2 inhibition, while COX-1 inhibition is the major cause of this classic adverse effects. Introduction of thiazolidinone may lead to the increase in the bulkiness leads to the preferential inhibition of COX-2 rather than COX-1 enzyme. The study aimed to synthesize derivatives of mefenamic acid with more potency and to decrease the drug's potential side effects, new series of 4-t
... Show MoreA pseudo-slug flow is a type of intermittent flow characterized by short, frothy, chaotic slugs that have a structure velocity lower than the mixture velocity and are not fully formed. It is essential to accurately estimate the transition from conventional slug (SL) flow to pseudo-slug (PSL) flow, and from SL to churn (CH), by precisely predicting the pressure losses. Recent research has showed that PSL and CH flows comprise a significant portion of the conventional flow pattern maps. This is particularly true in wellbores and pipelines with highly deviated large-diameter gas-condensate wellbores and pipelines. Several theoretical and experimental works studied the behavior of PSL and CH flows; however, few models have been suggested to pre
... Show MoreThis study aimed to determine the effect of green bismuth oxide (BiO) NPs against multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) from wound infections. Among 450 wound samples collected from patients admitted to the hospital, 200 P. aeruginosa isolates were identified. MDR strains of P. aeruginosa were detected by disc diffusion method. BiO NPs were synthesized using wild Bacillus subtilis (B. subtilis) strain and infrared spectroscopy, X-ray diffraction and scanning electron microscopy techniques. The antibacterial effect of the NPs compared to antibiotics against MDR strains was evaluated using a standard disk diffusion method. BiO NPs were synthesized at 0.005 M concentration of solution. According to the SEM im
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