Airborne coal dust mass measurements in underground bituminous coal mines can be challenged by the presence of airborne limestone dust, which is an incombustible dust applied to prevent the propagation of dust explosions. To accurately measure the coal portion of this mixed airborne dust, the National Institute for Occupational Safety and Health (NIOSH) developed a sampling and analysis protoco...

The influence of calcium source (limestone and oyster shell) and particle size (<0.1 mm; 0.85 to 2 mm) on laying performance, egg quality, and bone properties were examined in laying ducks by a 2 × 2 factorial arrangement of treatments. Longyan females (288) with similar BW at 24 wk of age were randomly allotted into 4 treatments, each with 6 replicates of 12 individually caged birds and studied...

1. This study investigated how the size of crevices might affect their effectiveness as refuges for diatom-dominated algal assemblages from the grazing minnow Campostoma anomalum. 2. Crevice size was manipulated by making fired-clay substrates, using moulds to produce eight substrates with pits from 1.17 to 22.0 mm diameter. Non-pitted clay-stones and limestone were also tested. Cages were used...

Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends in ecosystem recovery. We sampled...

Silica fume has been largely used in concrete in recent decades due to its effect on improvement of strength and &#10durability of concrete. On the other hand, attention has been recently paid to the use of limestone powder as a substitute for part of cement in concrete, basically because of its low price and its positive effect on the durability of concrete. The aim of the current study is the...

The objective of this study was to evaluate the effect of particle size of a dietary Ca source on egg production and eggshell quality when added to hens’ diets that have different levels of calcium. The experiment was carried out on 216 ISA Brown hens (25 to 70 weeks of age), allocated to 9 groups of 12 replicates (cages), with two birds in each cage. A 3 × 3 factorial arrangement was used, wit...

Evaporite calcitization within the Castile Formation of the Delaware Basin is more widespread and diverse than originally recognized. Coupled field and GIS studies have identified more than 1000 individual occurrences of calcitization within the Castile Formation outcrop area, which includes both calcitized masses (limestone buttes) and laterally extensive calcitized horizons (limestone sheets)...

Thermal decomposition of dolomite in the presence of CO2 in a calcination environment is investigated by means of in situ X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The in situ XRD results suggest that dolomite decomposes directly at a temperature around 700 °C into MgO and CaO. Immediate carbonation of nascent CaO crystals leads to the formation of calcite as an intermediate...

8 We analyze the role of limestone crystallinity on its CO2 capture performance when subjected 9 to carbonation/calcination cycles at conditions mimicking the Ca-looping (CaL) technology 10 for post-combustion CO2 capture. The behavior of raw and pretreated limestones (milled and 11 thermally annealed) is investigated by means of thermogravimetric analysis (TGA) tests under 12 realistic sorbent...

Limestone basements holding bronzes or other copper alloys artefacts such as sculptures, decorations and dedicatory inscriptions are frequently met both in modern and ancient monuments. In outdoor conditions, such a combination implies the corrosion products of the copper based alloy, directly exposed to rainwater, will be drained off and migrate through the porous surfaces, forming stains of d...