clay and feldspar

Heterogeneous reaction of NO

Topics: Aerosols; Arizona; Bentonite; Clay; Dust; Kaolin; Minerals; Nitrogen Dioxide

Today the terrestrial surface drives biogeochemical cycles on Earth through chemical weathering reactions mediated by the biological influence of soils. Prior to the expansion of life on to land, abiotic weathering may have resulted in different boundary conditions affecting the composition of the biosphere. Here we show a striking difference in weathering produced minerals preserved in the Mesoproterozoic Velkerri Formation. While the bulk chemistry and mineralogy is dominated by illite similar to many modern mudstones, application of a novel microbeam technology reveals that the initial detrital minerals were composed of mica (28%) and feldspar (45%) with only a trace amount (<2%) of typical soil formed clay minerals. The majority of illite and the high Al

Topics: Aluminum Silicates; Australia; Chemical Phenomena; Chemistry, Physical; Clay; Environmental Monitoring; Geological Phenomena; Geology; Minerals; Oceans and Seas; Potassium Compounds; Soil; Trace Elements; Weather

Antibiotic resistant bacteria persist throughout the world because they have evolved the ability to express various defense mechanisms to cope with antibiotics and the immune system; thus, low-cost strategies for the treatment of these bacteria are needed, such as the usage of environmental minerals. This paper reports the antimicrobial properties of a clay collected from Brunnenberg, Germany, that is composed of ferroan saponite with admixtures of quartz, feldspar and calcite as well as exposed or hidden (layered at inner regions) nano Fe(0). Based on the growth curves (log phase) of six antibiotic resistant bacteria (4 gram-negative and 2 gram-positive), we concluded that the clay acted as a bacteriostat; however, the clay was only active against the gram-negative bacteria (except for resilient Klebsiella pneumonia). The bacteriostatic mode of action was evidenced by the initial lack of Colony Forming Units on agar plates with growth registered afterward, certainly after 24h, and can be explained because interactions between membrane lipopolysaccharides and the siloxane surfaces of the clay. Labile or bioavailable Fe in the clay (extracted by EDTA or DFO-B) induced the quantitative production of HO as well as oxidative stress, which, nevertheless, did not account for by its bacteriostatic activity.

Topics: Aluminum Silicates; Anti-Bacterial Agents; Clay; Germany; Gram-Negative Bacteria; Gram-Positive Bacteria; Potassium Compounds

Many hirundine species construct their nests by carrying mud particles from adjacent areas. This study aimed to investigate for the first time the materials that mud-nesting hirundines choose for nest construction from a mineralogical and sedimentological perspective. For this purpose, we sampled nests of three sympatric species, namely the Barn Swallow (Hirundo rustica), the Red-rumped Swallow (Cecropis daurica) and the House Martin (Delichon urbicum), from southeastern Europe. Our results showed that all species tend to use clay minerals as a cement and especially smectite and illite and if these minerals are not present in the adjacent area, they use halloysite, kaolinite or chlorite. The amounts of clay minerals in the nests are generally low indicating that the studied species can accurately identify the properties of the nesting materials. Most of the non clay minerals that they use are the common, easily accessible colourless or white minerals with low specific gravity values such as quartz, feldspars and calcite. Grain size distribution analysis revealed that the amount of clay sized grains in the mud nests of all three species is relatively low, while the amount of larger grain particles decreases when the size of the non clay minerals is small. The Red-rumped Swallow showed an increasing preference for larger grain size particles and quartz, the Barn Swallow for finer grain size particles and calcite, and the preferences of the House Martin are in between the other two species. The three hirundine species present different nest building strategies and depending on the nest architecture, each of them seems to show preference for specific minerals and specific grain sizes.

Topics: Aluminum Silicates; Animals; Calcium Carbonate; Chlorides; Clay; Construction Materials; Kaolin; Nesting Behavior; Potassium Compounds; Quartz; Swallows

The radioactive fallout cesium (¹³⁷Cs) in the sewage sludge ashes (SSAs) produced in Japan after the Fukushima Daiichi Nuclear Accident was tested. Five samples of SSAs produced in 2011 and 2012 were tested. Two of the samples contained ¹³⁷Cs (23 and 9.6 kBq/kg, respectively) above the radioactivity criterion (8 kBq of radioactive Cs/kg of solid) for controlled landfill disposal in Japan. The mineral components of SSA are roughly divided into two groups: an HCl-soluble phase mainly composed of phosphates and oxides; and silicates, including quartz, feldspar, and clay. Both phases contained ¹³⁷Cs. The majority (up to 90%) of ¹³⁷Cs was contained in the HCl-soluble phase. Among the HCl-soluble subphases, Fe-bearing phases that were probably iron oxides were mainly responsible for ¹³⁷Cs retention. No positive evidence was obtained that showed that phosphate-bearing phases, which were included most in SSAs along with the silicate phase, retained ¹³⁷Cs. Pre-pulverizing SSAs and heating them at 95 °C in a 6 M or a concentrated aqueous HCl was the most effective method of dissolving the HCl-soluble phase. The radioactivity concentrations of ¹³⁷Cs in all the HCl-treatment residues were below the radioactivity criterion. This residue was mostly composed of silicates. After static leaching tests of the residue at 60 °C for 28 days, no ¹³⁷Cs was detected in simulated environmental water leachates (pure water and synthetic seawater), demonstrating that 137Cs in the residue is very stably immobilized in the silicates.

Topics: Aluminum Silicates; Cesium Radioisotopes; Clay; Fukushima Nuclear Accident; Geography; Hot Temperature; Hydrochloric Acid; Incineration; Japan; Microscopy, Electron, Scanning; Oxides; Phosphates; Potassium Compounds; Radiation Monitoring; Radioactive Fallout; Seawater; Sewage; Silicates; Solubility; Water Pollutants, Radioactive

The present study was carried out to evaluate the impact of the effluents and the solid wastes generated by a giant pulp and paper mill in the northeastern part of India on soil mineralogy of the area. The impacts were monitored by analysis of soil samples from seven sites located in the potential impact zone and a control site where any kind of effluent discharge or solid waste dumping was absent. The soil belonged to medium texture type (sandy clay loam, sandy loam, loamy sand, and silt loam), and the soil aggregate analysis indicated higher levels of organic carbon, pH, electrical conductivity, effective cation exchange capacity, and mean weight diameter at sites receiving effluents and solid wastes from the pulp and paper mill. Depletion in soil silica level and in feldspar and quartz contents and rise in iron and calcium contents at the sites receiving effluents from the pulp and paper mill indicated significant influence on soil mineralogy. The soil contained a mixture of minerals consisting of tectosilicates (with silicate frameworks as in quartz or feldspar), phylosilicates (layered clays like kaolinite, smectite, chlorite, illite, etc.), and carbonates. Absence of pure clay minerals indicated a state of heterogeneous intermediate soil clay transformation. The significance of the mixed mineralogy in relation to the disposal of effluents and dumping of solid wastes is discussed in details.

Topics: Aluminum Silicates; Clay; Environmental Monitoring; India; Industrial Waste; Paper; Potassium Compounds; Soil; Solid Waste; Waste Disposal, Fluid; Wastewater

Evaluation of CO₂ solubility-trapping and mineral-trapping by microbial-mediated process was investigated by lab experiments in this study. The results verified that microbes could adapt and keep relatively high activity under extreme subsurface environment (pH<5, temperature>50 °C, salinity>1.0 mol/L). When microbes mediated in the CO₂-brine-sandstone interaction, the CO₂ solubility-trapping was enhanced. The more biomass of microbe added, the more amount of CO₂ dissolved and trapped into the water. Consequently, the corrosion of feldspars and clay minerals such as chlorite was improved in relative short-term CO₂-brine-sandstone interaction, providing a favorable condition for CO₂ mineral-trapping. Through SEM images and EDS analyses, secondary minerals such as transition-state calcite and crystal siderite were observed, further indicating that the microbes played a positive role in CO₂ mineral trapping. As such, bioaugmentation of indigenous microbes would be a promising technology to enhance the CO₂ capture and storage in such deep saline aquifer like Erdos, China.

Topics: Aluminum Silicates; Calcium Carbonate; Carbon Dioxide; China; Clay; Clostridium; Groundwater; Hydrogen-Ion Concentration; Klebsiella; Minerals; Plesiomonas; Potassium Compounds; Salinity; Salts; Solubility; Temperature; Water Microbiology; Water Pollutants

In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.

Topics: Aluminum Silicates; China; Clay; Gamma Rays; Geology; Magnetic Resonance Spectroscopy; Oil and Gas Fields; Potassium Compounds; Radiation Monitoring; Uranium

Infrared spectroscopy has been employed in a study of the degradation of heritage Sydney sandstone used in St. Mary's Cathedral in Sydney, Australia. Spectra were used to characterise the clay components taken from weathered and unweathered sandstone blocks removed from the Cathedral as part of a restoration programme. Two types of kaolin clays - kaolinite and its polymorph, dickite - have been identified. A higher amount of dickite present in the clay of weathered sandstone indicated that a kaolinite-to-dickite transformation occurs upon weathering. X-ray photoelectron spectroscopy was also used to confirm the presence of a more thermally stable polymorph of the kaolinite in the sandstone.

Topics: Aluminum Silicates; Clay; Color; Construction Materials; Kaolin; Minerals; New South Wales; Oxidation-Reduction; Potassium Compounds; Quartz; Silicon Dioxide; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis; Weather; X-Rays

The aim of this work was to evaluate the use of mineral coal fly ash as a raw material in the production of ceramic tiles. The samples of fly ash came from Capivari de Baixo, a city situated in the Brazilian Federal State of Santa Catarina. The fly ash and the raw materials were characterized regarding their physical chemical properties, and, based on these results; batches containing fly ash and typical raw materials for ceramic tiles were prepared. The fly ash content in the batches varied between 20 and 80 wt%. Specimens were molded using a uniaxial hydraulic press and were fired. All batches containing ash up to 60 wt% present adequate properties to be classified as several kinds of products in the ISO 13006 standard () regarding its different absorption groups (pressed). The results obtained indicate that fly ash, when mixed with traditional raw materials, has the necessary requirements to be used as a raw material for production of ceramic tiles.

Topics: Aluminum Silicates; Calcium Carbonate; Carbon; Ceramics; Clay; Coal; Coal Ash; Conservation of Natural Resources; Particulate Matter; Potassium Compounds; Waste Management