The Guangxi Zhuang Autonomous Region is an important manganese ore district in Southwest China, with resource reserves accounting for 23% of the total China. Xialei deposit (Daxin County, Guangxi) first super-large discovered Mn oxide supergene oxidation zone was characterized using scanning electron microscopy (SEM), energy spectrometer (EDS), transmission (TEM, HRTEM), and X-ray diffraction a...

Two new species of Leptokoenenia Condé 1965 (Eukoeneniidae: Palpigradi), Leptokoenenia pelada sp. nov. and Leptokoenenia thalassophobica sp. nov., are described based on both male and female specimens collected in iron ore caves from the Brazilian Amazon. This is the first record of the genus for the Americas. Furthermore, a new combination is stated for Eukoenenia gallii based on its morphology.

A fundamental study was carried out on the high-temperature zone flow resistance during iron ore sintering. In present work, firstly, quartz sand was used to replace iron ores to investigate the impact of temperature if bed structure has no change; then a three-layer bed structure was used to explore the primary factors controlling high-temperature zone structure for airflow. The zone where tem...

The collapse of the Fundão tailings dam at Mariana (State of Minas Gerais, Brazil) started a huge human tragedy and likely the most serious environmental disaster in recent Brazilian history. The dam had contained waste from processing iron ore from mines owned by Samarco, a joint venture company of the Brazilian Vale S.A. and the Anglo-Australian BHP Billiton Ltd. Following ineffective attempt...

The risks in the evaluation of mining projects are directly related to the probability of errors in the estimates, and, as the estimates are based on sampling results, this activity must be performed in a careful and planned way, to prevent surprises at the beginning of operation. To validate the representativeness of the borehole samples selected for the mineral processing studies, the geologi...

A distributed feedback channel waveguide laser in erbium-doped aluminum oxide on a silicon substrate is reported. The optically pumped laser has a threshold pump power of 15 mW and emits 3 mW in single-frequency operation at 1545.2 nm wavelength with a slope efficiency of 6.2% and linewidth of 15 kHz. Keywords—Distributed feedback (DFB) laser; waveguide laser; erbium-doped laser; Bragg gratings...

This project presents the results of an experimental investigation of graphene oxide on physical properties of concrete. This article aims to find out the optimum quantity of graphene oxide required to achieve maximum compressive, tensile and flexural strength of concrete. Graphene oxide was added to the concrete in three mix proportions. Graphene oxide content were varied by 0.05%, 0.1%, 0.2% ...