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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Dentistry, Shiraz University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: concentration,Dental leakage,Calcium-Enriched Mixture Cement
- چکیده:
- چکیده انگلیسی: Statement of the Problem: Sealing ability is one of the most important factors for successful endodontic treatment. Some studies have shown that the powder to liquid ratio can influence the properties of dental materials. Subsequently, this may happen for those used for sealing in endodontics.Purpose: The purpose of this research was to assess the microleakage of calcium-enriched mixture cement (CEM cement) apical plug in different powder to liquid ratio.Materials and Method: Ninety-six extracted human single root and single canal teeth were decoronated. Working length was determined using ≠15 k-file. Canal preparation was performed using step back method. Samples were divided into 3 groups randomly. CEM cement was placed into the canal with 1.13, 2.27 and 3.40 powder to liquid ratio in the group 1, 2 and 3, respectively. After complete setting of CEM cement, the micro leakage value was evaluated using fluid filtration method. Data were analyzed using ANOVA and Scheffe tests.Results: The bubble movement in three groups showed a statistically significant difference (p < 0.001). Minimum and maximum bubble movements were observed in the group with powder to liquid ratios of 3.40 and 1.13 respectively.Conclusion: Increased CEM Cement powder to liquid ratio will increase the sealing ability of this material as apical plug. Considering the conditions of this study, the powder to liquid ratio of 3:40 provided the best sealing ability.
- انتشار مقاله: 01-07-1396
- نویسندگان: Fatemeh Ayatollahi,Fatemeh Zarebidoki,Seyed Hossein Razavi,Mahdi Tabrizizadeh,Reza Ayatollahi,Mahyar Heydarigujani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Materials Forming
- نوع مقاله: Journal Article
- کلمات کلیدی: Severe Plastic Deformation,Simple shear extrusion,Superplasticity,Shear punch test
- چکیده:
- چکیده انگلیسی: The strain rate sensitivity (SRS) of Mg–1.5 wt% Gd processed by conventional extrusion and 2 passes of simple shear extrusion (SSE) was investigated by shear punch testing. Shear punch tests were conducted at initial shear strain rates in the range of 0.003–0.3 s-1 and at temperatures in the range of 573–773 K. A fine-grained microstructure with an average grain size of about 2.5 µm, obtained after 2 passes of SSE, resulted in high SRS index (m-value) of 0.4 at 723 K. The calculated activation energy for 2 passes deformed alloy is 116 kJ/mol which is higher than the activation energy of grain boundary diffusion in magnesium (75 kJ/mol). This higher amount of activation energy can be attributed to the presence of gadolinium in this alloy. This SRS index together with an activation energy of 116 kJ/mol are indicative of a superplastic deformation behavior dominated by grain boundary sliding accommodated by grain boundary diffusion at 723 K.
- انتشار مقاله: 26-11-1394
- نویسندگان: Nazanin Bayat Tork,Seyed Hossein Razavi,Hassan Saghafian,Reza Mahmudi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Earth Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Central Iran,Petrology,Troud,Back-arc,crust melting
- چکیده:
- چکیده انگلیسی: The area of study is located 120 Km north-east of Shahrood city. In terms of structure and geological classification, this area is located in the northern part of central Iran zone. Granitoids of Troud ranging from monzonite to granite. The main minerals of granitoids are quartz, plagioclase, and orthose. The accessory minerals are biotite, hornblende, sphene, and opaque minerals. Various textures of granular, graphic and prethite are observed in these rocks. Based on various diagrams of major and trace elements, this rock is I-type arc calk-alkaline, Meta to para-aluminous with continental origin form at subduction zone. All these characteristics, combined with low Al2O3/(FeO + MgO + TiO2) and (Na2O +K2O)/(FeO + MgO + TiO2) ratios and high Mg# values, suggest an origin through dehydration melting of alkaline mafic of lower crustal source rocks.
- انتشار مقاله: 16-03-1395
- نویسندگان: Elham Shah Hosseini,Afshin Ashja Ardalan,Mohammad Hashem Emami,Mohammad Hossein Razavi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Heterocyclic Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده:
- چکیده انگلیسی: Crystallographic data analyses indicate that three types of prolinium cations, along with two types of hydrogen bonding, produce and stabilize the helical structure of triprolinium 12-phosphomolybdate. There are similarities between this organic-inorganic compound and peptides/proteins. The stronger “conventional” hydrogen bonds and the less common C-H…O attractions play critical roles in generating and stabilizing the DNA-like network
- انتشار مقاله: 28-03-1397
- نویسندگان: Masoud Mirzaei,Ali R. Salimia,Mohammad H. Alizadeh,Hossein Eshtiagh-Hosseini,Hossein Razavi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Heterocyclic Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Protein,Hydrogen bonding,Proline,Molybdenum,Polyoxometallates,Hybrid,Keggin,Peptide
- چکیده:
- چکیده انگلیسی: Crystallographic data analyses indicate that three types of prolinium cations, along with two types of hydrogen bonding, produce and stabilize the helical structure of triprolinium 12-phosphomolybdate. There are similarities between this organic-inorganic compound and peptides/proteins. The stronger “conventional” hydrogen bonds and the less common C-H…O attractions play critical roles in generating and stabilizing the DNA-like network.
- انتشار مقاله: 05-03-1395
- نویسندگان: Masoud Mirzaei,Ali R Salimi,Mohammad H. Alizadeh,Hossein Eshtiagh-Hosseini,Hossein Razavi
- مشاهده