Rock coatings formed on petroglyphs at Petrified Forest National Park both preserve the art from erosional processes and provide tools to understand the art’s chronology. Erosional processes of rock fall from fissuresol wedging, splintering of sandstone, and flaking are somewhat offset by case hardening surfaces by addition of rock coatings. 20th century graffiti can be distinguished from truly...

to evaluate the relationship between total organic carbon (toc) and rock-eval s2 (petroleum potential) of petroleum source rocks, atotal of 180 outcrop samples from the black organic matter–rich facies of mesozoic strata from a locality of southwest of iran wereinvestigated using rock-eval vi pyrolysis and leco carbon analyzer. the linear regression is applied to determine the correlationbetwee...

A method has been developed to infer the wettability of steam-water-rock systems based on the relationship between permeability and capillary pressure by Purcell. The Purcell model was extended to two-phase flow to verify whether the wettability is a function of water saturation. The results calculated using the experimental data showed that the wettability index in drainage was greater than th...

A comprehensive investigation was carried out to minimize the cost price of the rock fragmentation process including: drilling, blasting, secondary blasting and separating the large boulders (oversize rocks) while loading, until the optimized fragmentation, powder factor and ratio of burden (B) to blasthole diameter (?h) were achieved by doing several stages of drilling and blasting practically...

Understanding the responses of soil organic carbon to an increase in global temperature is crucial to estimate potential feedbacks on global warming. In such a context, Rock-Eval pyrolysis has been recently proposed as a screening tool to investigate soil organic matter (SOM) chemistry and vulnerability. In order to test the validity of Rock-Eval as an indicator of SOM chemistry and of OM trans...

The effect of brushing with two abrasive levels on the fluoride release of high-viscosity glass ionomers (GIs) was investigated. Forty-eight GI discs were fabricated and randomly assigned to one of the four groups. Treatments, performed for 30 days, included exposure to a carboxymethylcellulose (CMC) solution without fluoride (CMC-F), CMC with 275 ppm fluoride (CMC+F), CMC with fluoride plus br...

This study compared the traditional radiotracer method (Rt) for determination of dentifrice abrasivity to the recently introduced surface profile (Sp) method (ISO 11609). Specimens from human root dentin were prepared for each method and randomly assigned to 8 dentifrice/abrasive groups (n1⁄48), of wide abrasivity range. Aqueous dentifrice slurries or abrasive suspensions were used to brush spe...

Sarvak formation, with the middle cretaceous (Cenomanian) age, is one of the stratigraphic units of the Bangestan group in the southern Iran. The carbonate rocks of this formation form the reservoir rock in the study field. Generally, Sarvak formation is subdivided into three members including Mishrif, Khatiyah, and Maddud in the Persian Gulf, and the average thickness of the reservoir unit (i....

Since rocks are aggregates of mineral particles, the effect of mineral microstructure on macroscopic mechanical behaviors of rocks is inneglectable. Rock samples of four different particle shapes are established in this study based on clumped particle model, and a sphericity index is used to quantify particle shape. Model parameters for simulation in PFC are obtained by triaxial compression tes...

Re-expansion of a collapsed lung increases the microvascular permeability and causes re-expansion pulmonary edema. Neutrophils and their products have been implicated in the development of this phenomenon. The small GTP-binding proteins Rho and its target Rho-kinase (ROCK) regulate endothelial permeability, though their roles in re-expansion pulmonary edema remain unclear. We studied the contri...