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Incrustation Problems in Landfill Drainage Systems
Published in T. H. Christensen, R. Cossu, R. Stegmann, Landfilling of Waste: Barriers, 2020
Mathias Brune, Hans Günter Ramke, Hans Jürgen Collins, Hans H. Hanert
Table 5 lists the composition of some selected samples of incrustation material from the columns. Besides a proportion of insoluble residue derived from the drainage material, the incrustation material from the pores in the gravel and from the geotextile consisted mainly of organic material, carbonate and calcium, whereby the calcium may be assumed to be mainly in the form of carbonate. However, significant amounts of iron and sulphur were also present. The addition of hydrochloric acid to the samples caused effervescence and the smell of hydrogen sulphide, which suggests the presence of iron sulphide, particularly. Thus, the incrustation material taken from the columns corresponds to that obtained from the drainage systems of the investigated landfill sites.
Minerals
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Given a single property, for example luster, it is possible to divide minerals into groups. In the case of luster, we usually divide minerals into those that are metallic and those that are nonmetallic. There are, however, many metallic and many nonmetallic minerals; other properties must be considered if minerals are to be identified. Nonmetallic minerals, for instance, can be divided further based on more subtle luster differences. Other properties—including diaphaneity, crystal shape, cleavage, parting, fracture, and hardness—are also diagnostic. Ultimately, minerals can be identified by name or at least placed in small groups. It is tempting, then, to come up with a standard list of properties that should be evaluated when identifying minerals. However, most mineralogists know that, depending on the sample and circumstances, some properties are more important than others. Rather than going through a long list or filling out a standard table, experienced mineralogists focus on the properties that are most diagnostic. Sometimes a single property, such as strong effervescence by hydrochloric acid (diagnostic of calcite), may serve for mineral identification. At first, mineral identification may seem tedious, but with a little experience, it is possible to find shortcuts to make the process more efficient.
Emerging Technology: The Bases For New Generations of Pesticide Formulation
Published in Chester L. Foy, David W. Pritchard, and Adjuvant Technology, 2018
Effervescence is used most commonly to obtain rapid dispersion or solution of tablets. Special packaging is required to exclude water which could trigger chemical reaction leading to premature effervescence and evolution of carbon dioxide. Tablets have been produced that contain internal desiccant to ensure tablet stability.53 Other developments include discovery of new disintegrants to speed dispersion of noneffervescent tablets.
Designing of porous PMMA/diopside bone cement for non-load bearing applications
Published in Journal of Asian Ceramic Societies, 2020
Rajan Choudhary, Senthil Kumar Venkatraman, Inna Bulygina, Fedor Senatov, Sergey Kaloshkin, Sasikumar Swamiappan
Eggshell-derived calcium nitrate solution was utilized as a calcium source for the preparation of diopside. Eggshells were collected from VIT mess and washed under the running tap water to clean their surfaces. The bacterial contamination and unnecessary protein coatings were eliminated by boiling at 120°C for 3 hours with continuous stirring on a magnetic stirrer. The boiled eggshells were transferred to a sheet of tissue paper to absorb water droplets from the surface. Later, the eggshells were dried in a hot air oven at 150°C for a day. The dried eggshells were crushed and grinded manually to fine powders by using agate mortar and pestle. The powdered eggshell was further utilized to prepare a 1 M calcium nitrate solution by adding 37.5 ml of concentrated nitric acid to 25 gm eggshell powder. A sudden brisk effervescence giving foam-like appearance was noticed due to the liberation of carbon dioxide (CO2) and water (H2O). The foamy mixture was kept undisturbed for about 12 hours to facilitate the completion of the reaction. The unreacted content of the solution was separated by filtering through Whatman 41 filter paper. The resultant filtrate was collected in a standard flask and made up to 250 ml by using deionized water. The concentration of calcium ion in the stock solution was estimated by ethylenediaminetetraacetic acid (EDTA) titration by following the procedure mentioned elsewhere [24]. The estimated calcium ion concentration in the eggshell stock solution was observed to be 0.99 molar.
James Smithson on the Calamines: Chemical Combination in Crystals
Published in Ambix, 2018
For his study Smithson selected several specimens that were well formed and homogeneous, having purchased them from a German minerals dealer. These were sourced from well-known locations,37 and were of much higher quality and purity than was usually mined. He chose them not as typical but as representative of the mineral in a pure state. For each sample he presented a careful compositional analysis supplemented with natural historical observations. This included evidence from the blowpipe, determinations of specific gravity, and tests for effervescence or the formation of a jelly (indications of presence of carbonic acid and of quartz, respectively). Where possible, he also included details about the crystal form, in one case providing a diagram with angle measurements.