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Alloy AD730TM is a recently developed Nickel base superalloy for application as turbine disk in modern gas turbines with improved thermal efficiency. Ingot casting followed by open die-forging and then heat treatments are the main manufacturing steps for the production of parts made of this alloy. Solution heat treatment operations are applied at different stages of the manufacturing in order to ease the deformation processing and/or prepare the microstructure for final heat treatment. In this research, the influence of various solution heat treatment schedules on morphology and distribution of the γ′ phase are investigated and documented. The obtained results will contribute to a better understanding of microstructure evolution of AD730TM during solution heat treatments. Differential Thermal Analysis (DTA) is used for the purposes of measurement of temperatures of phase transformations of the alloy. Based on DTA results, three solutionizing temperatures and three holding times were selected for performing and assessing the solution heat treatment process. Optical and electron microscopy were used to study the morphological evolution as well as the coarsening and dissolution of secondary phases at solvus and subsolvus temperatures. The results indicated that precipitate agglomeration and Ostwald ripening are the governing mechanisms during the initial stages and splitting and partial dissolution of γ′ precipitates takes place during subsolvus solution treatments.

Background: Traumatic dental injuries (TDIs) are one of the most common dental problems among children and adolescents, which usually occur in the anterior parts of the mouth and have great impact on the patient's physical and mental health. Therefore, dentist's knowledge and effective measures in the treatment of TDI are the most important factors in improving the prognosis of these teeth. Aims: The aim of this study was to evaluate the knowledge of general dentists working in Bojnurd and also 6th-year dental students about the treatment of such injuries. Materials and Methods: In this cross-sectional study, a questionnaire was provided to 70 general dentists and 6th-year dental students, including personal information and questions related to the knowledge of general dentists, on how to deal with various TDIs by available methods. Data were analyzed using t-test, Chi-square test, Kruskal–Wallis test, and analysis of variance, Spearman's, and Pearson's correlation coefficient. Results: Regarding general dentists' knowledge about dentoalveolar trauma: 39 (55.7%) were moderate, 28 (40%) were good, and 3 (4.3%) were excellent. The mean value knowledge of dentists and dental students was 8.18 ± 1.98. There was no significant relationship between age, gender, place of work, university of study, desire for education, and self-evaluation of dentists and level of awareness (P = 0.26, P = 0.61, P = 0.47, P = 0.93, P = 0.35, and P = 0.57, respectively). Conclusions: The results of our study indicate that majority of the participants are moderately aware of TDIs and the type of treatment, and due to the increasing prevalence of dental trauma and its high complications, especially in children, the need to make appropriate plans to update the level of knowledge of general dentists in the management and treatment of TDI increases.

The Sar Cheshmeh porphyry copper deposit is located in the Central Iranian Volcanic-Sedimentary Belt (CIVSB). The hydrothermal alteration zones are well developed within and around the porphyry stock. Given the poor soil and vegetation cover in this area, we evaluated the usefulness of multispectral remote sensing data derived from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Enhanced Thematic Mapper Plus (ETM+) images and airborne magnetic-radiometric data for hydrothermal alteration mapping at a local scale. Principal component analysis (PCA), band ratios and the spectral angle mapper (SAM) technique were applied to the multispectral data sets to map hydrothermally altered rocks. PCA and band ratios were also applied to the airborne geophysical data. The overall results showed that the multispectral remote sensing data sets resulted in more accurate hydrothermal alteration mapping and lithological discrimination in the study area as compared with the airborne geophysical data. The radiometric data are also useful in enhancing areas with potassic alteration. [ABSTRACT FROM AUTHOR]

In this paper, a new entropy-based approach is developed for assessing the location of salinity monitoring stations in the Tehran Aquifer, Tehran, Iran. To find the optimal distance among stations, the measure of Transinformation in the Entropy Theory is used. Then a Transinformation-Distance (T-D) curve is developed and used in a multi-objective GA-based optimization model, which provides the best locations for monitoring stations. Because of the large area of the Tehran aquifer and significant spatial variations of the Electrical Conductivity (EC) of the groundwater in the study area, the C-means clustering method is used to classify the study area to some homogenous zones. The optimization model is applied to each zone to find the optimal location of monitoring stations. The results show the applicability and the efficiency of the model in assessing the groundwater monitoring systems. [ABSTRACT FROM AUTHOR]