Knowledge of the orientation of horizontal in situ stresses is important to some areas of oil and gas field development plans. Borehole breakouts observed in image logs and drilling-induced fractures are the main parameters for the determination of the stresses’ directions in situ. In this work, the orientations of borehole breakouts were investigated as a function of depth in oil wells A and ...

in this study, laser induced breakdown spectroscopy (libs) is used for qualitative analysis of healthy and carious teeth. the technique of laser ablation is receiving increasing attention for applications in dentistry, specifically for the treatment of teeth such as drilling of micro-holes and plaque removal. in the process of ablation a luminous micro-plasma is normally generated which may be ...

Abstract. Knowledge of the undisturbed stress state in subsurface is key interest for safety assessment deep geological repositories. However, magnitude data are usually sparse, available subject to large uncertainties, and acquisition new expensive. This highlights importance 3D geomechanical-numerical models that provide full tensor throughout a volume interest. Nevertheless, such model needs...

PURPOSE Bone drilling is a major part of orthopaedic surgery performed during the internal fixation of fractured bones. At present, information related to drilling force, drilling torque, rate of drill-bit penetration and drill-bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. METHODS This study demonstrates that ...

For years, drilling engineers have been faced with the challenge of wells through naturally fractured reservoirs that are present around world. During drilling, pressure at bottomhole a well is frequently intentionally higher than formation pressure, which can result in loss mud surrounding rocks. cementing, even it during because cement slurry density mud. Therefore, if natural or induced frac...

Geothermal and unconventional hydrocarbon reservoirs are often characterized by low permeability and porosity. So, they are difficult to produce and require stimulation techniques, such as thermal shear deactivation and hydraulic fracturing. Fractures provide porosity for fluid storage and permeability for fluid movement and play an important role in production from this kind of reservoirs. Hen...

Laboratory experiments demonstrate that finely divided solid materials (bentonite, iron oxide, magnesium oxide and manganese oxide) can form stable o/w emulsions for NAPLs such as PCBs, TCE, and diesel fuel. These emulsions, referred to as Pickering emulsions, are stabilized by finely divided solid materials that coat the NAPL-water interface; they do not require the presence of a surfactant to...

Periprosthetic proximal femoral fractures are a major challenge for the orthopaedic surgeon, with a continuously increasing incidence due to aging populations and concordantly increasing numbers of total hip replacements. Surgical decision-making mainly depends on the stability of the arthroplasty, and the quality of bone stock. As patients final outcomes mainly depend on early mobilization, a ...