Abstract Patterns of state formation have crucial implications for comparative economic development. Diamond (1997) famously argued that “fractured land” was responsible China’s tendency toward political unification and Europe’s protracted polycentrism. We build a dynamic model with granular geographical information in terms topographical features the location productive agricultural land to qu...

Handling flow through fractured media is critical for transient pressure and flow analysis in shale gas reservoirs, because gas production from such low-permeability formations relies on fractures, from hydraulic fractures and fracture network to various-scaled natural fractures, to provide flow channels for gas flow into producing wells. This study presents a numerical investigation of pressur...

block heights and capillary continuity between matrix blocks play paramount role in the sensitivity analysis and therefore the history matching of cumulative oil production and production rate of carbonated fractured reservoirs. in this study, the influence of these parameters upon cumulative production and recovery factor of an iranian fractured reservoir were studied by the usage of a simulat...

Hydraulic fracturing is an important method of reservoir stimulation in the exploitation of geothermal resources, and conventional and unconventional oil and gas resources. In this article, hydraulic fracturing experiments with shale, sandstone cores (from southern Sichuan Basin), and granite cores (from Inner Mongolia) were conducted to investigate the different hydraulic fracture extension pa...

In petroleum exploration and production, fractures are one of the most common and important geological structures, for they have a significant effect on reservoir fluid flow. Despite their importance, detection and characterization of natural fractures remains a difficult problem for engineers, geologists and geophysicists. This paper presents a technique for the identification and characteriza...

In recent years, more attention has been given to the mechanism of disease induction caused by the surface properties of minerals. In this respect, specific research needs to be focused on the biologic interactions of oxygen radicals generated by mineral particles resulting in cell injury and DNA damage leading to fibrogenesis and carcinogenesis. In this investigation, we used electron spin res...

in the present study, the mechanical properties and fracture mechanisms of two powder metallurgy low alloy steels, i.e. distaloy dh and distaloy hp, were investigated. all samples were sintered at 1120 ºc for 30 min in n2/h2 atmosphere. for evaluation of the effect of cooling rate on final properties, samples were cooled from sintering temperature with two different cooling rates. in addition, ...

OBJECTIVE To understand the potential fracture mechanism of sternal wires, we collected extracted stainless steel sternal wires from patients with sternal dehiscence following open-heart operations. Surface alterations and fractured ends of sternal wires were inspected and analyzed. METHODS Eight fractured and 12 non-fractured wires extracted from five patients (closure method: figure-of-eigh...

Al2O3-SiO2 diphasic gel was synthesized by sol gel route from aluminium nitrate and silicic acid following aqueous phase colloidal interaction. The precursor gel powder was thoroughly characterized by chemical analysis, measurement of surface area and bulk density measurement. The gel powder was further characterized by thermogravimetry, XRD diffraction stud...