Open pit limit optimization considering economic profit,ecological costs and social benefits

Pit limit design has,up to date,focused mainly on maximization of economic profit alone,with environmental and social issues largely ignored.This paper focuses on incorporating both environmental and social issues in the pit limit design process and provides an approach to pit limit optimization that is in compliance with sustainable development.The case study demonstrates that ecological costs have a substantial down-sizing effect and social benefits have a substantial up-sizing effect on the optimal pit limit.When the ecological costs are factored in,the optimal pit limit is 37.5%smaller than the economically optimal pit limit.However,when the social benefits are factored in,the optimal pit limit is 48.3%larger than the economically optimal one.The overall optimal pit limit,with the economic profit,ecological costs and social benefits simultaneously considered,is a result of balancing conflicting goals of maximizing economic profit,minimizing ecological cost,and maximizing social benefit.

Epitaxial growth and transport properties of compressively-strained Ba_(2)IrO_(4) films

Ba_(2)IrO_(4) is a sister compound of the widely investigated Sr_(2)IrO_(4) and has no IrO_(6) octahedral rotation nor net canted antiferromagnetic moment,thus it acts as a system more similar to the high-T_(c) cuprate.In this work,we synthesize the Ba_(2)IrO_(4) epitaxial films by reactive molecular beam epitaxy and study their crystalline structure and transport properties under biaxial compressive strain.High resolution scanning transmission electron microscopy and x-ray diffraction confirm the high quality of films with partial strain relaxation.Under compressive epitaxial strain,the Ba_(2)IrO_(4) exhibits the strain-driven enhancement of the conductivity,consistent with the band gap narrowing and the stronger hybridization of Ir-t_(2g) and O-2p orbitals predicted in the first-principles calculations.