Based on the engineering background of water dissolving mining for hydrocarbon storage in multi-laminated salt stratum, the mixed mode fracture toughness and fracture trajectory of gypsum interlayers soaked in half-saturated brine at various temperatures (20°C, 50°C and 80°C) were studied by using CSNBD (centrally straight-notched Brazilian disc) specimens with required inclination angles (0°, ...

the aim of this research was to study the relationships between presence of plant species and environmental factors in garizat rangelands of yazd province and providing their predictive habitat models. after delimitation of the study area, sampling was performed using randomized-systematic method. accordingly, vegetation data including presence and cover percentage were determined in each quadr...

Abstract: The linear expansion, early-age compressive strength and setting times of the binary mixtures of gypsum and Portland cement clinkers of relatively low C3A-contents were investigated. For this reason, type 1, 2, and 5 of Portland cement-clinkers were selected and a number of binary mixtures were designed. At relatively lower percentages of gypsum (about 5%), the early strength behavior...

The dehydration of gypsum CaSO4.2H20 has been studied, at negligible water vapour pressure, by in situ infrared (IR) spectroscopy and by thermogravimetry to determine whether intermediate phases (CaSO4.nH20) exist, other than the hemihydrate with n=0.5, and also to compare the mechanism of the dehydration process when measured by two techniques with very different correlation lengths. Thermogra...

statement of problem: accurate impressions are one of the most critical factors in achieving acceptable restorations. when pouring the impressions of implant supported restorations, soft materials like silicone and polyether are used to reconstruct the gingival form around the implants. to the best of our knowledge, no study has been conducted on the comparison of the accuracy of these soft mat...

A dissolved methane sensor based on silicone tube was designed, constructed and optimized.The silicone tube diameter, silicone tube length and helium flow rate (as the carrier gas(were considered as process parameters to be optimized.A continuous stream of helium (50 mL/min) was directed through the tubing, sweeping out the...