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Chestnut
Published in Debashis Mandal, Ursula Wermund, Lop Phavaphutanon, Regina Cronje, Temperate Fruits, 2021
Gabriele L. Beccaro, Dario Donno, Michele Warmund, Feng Zou, Chiara Ferracini, Paolo Gonthier, Maria Gabriella Mellano
Manure and mineral fertilizers are often incorporated into the soil. In Italy 40–50 ton/ha of cow manure is soil incorporated at a depth of 20–30 cm, resulting in an organic matter content of at least 2%. Mineral fertilizers with phosphorus (10–20 ppm) and potassium (100–150 ppm) are applied as mineral superphosphate and potassium sulfate, respectively. Nitrogen, easily leached away, is applied during the spring (250 g/tree of ammonium sulfate or ammonium nitrate) to stimulate vegetative growth (Table 10.1).
Components of Energetic Compositions
Published in John A. Conkling, Christopher J. Mocella, Chemistry of Pyrotechnics, 2019
John A. Conkling, Christopher J. Mocella
Sulfur has a particularly low (119°C) melting point. It is a rather poor fuel in terms of heat output, but it frequently plays another very important role in pyrotechnic compositions. It can function as a “tinder” or a fire starter. Sulfur undergoes exothermic reactions at low temperature with a variety of oxidizers, and this heat output can be used to trigger other, higher energy reactions with better fuels. Sulfur’s low melting point provides a liquid phase, at low temperature, to assist the ignition process. The presence of sulfur, even in small percentage, can dramatically affect the ignitibility and ignition temperature of high-energy mixtures. Sulfur, upon combustion, is converted to sulfur dioxide gas and to sulfate salts (such as potassium sulfate—K2SO4). Sulfur is also found to act as an oxidizer in some mixtures, winding up as the sulfide ion (S2−) in species such as potassium sulfide (K2S), a detectable component of black powder combustion residue, as well as winding up as zinc sulfide (ZnS) in zinc–sulfur compositions.
Application of X-ray diffractometry and scanning electron microscopy to study the transformation of carnallite and thenardite to schoenite at 25 °C
Published in Chemical Engineering Communications, 2020
Qingyu Hai, Huaide Cheng, Haizhou Ma, Jun Li, Xiwei Qin
Potassium is an essential nutrient for plant growth (Dave and Ghosh, 2006). It is often provided as potassium chloride (sylvite), which is termed MOP (muriate of potash) in the agriculture sector. Potassium sulfate (arcanite), which is known as SOP (sulfate of potash), is recommended for chloride-sensitive crops. This fertilizer, which is produced commonly by chemical reactions, is rarely found in nature. Nowadays, almost half of world’s potassium sulfate is produced from KCl and H2SO4 by the well-known Mannheim process (Su et al., 2016). Less direct methods of production include transformation reaction of other minerals such as phosphogypsum and K2CO3 (Ennaciri et al., 2013), gypsum and KCl (Lozano and Wint, 1982; Fernández-Lozano and Wint, 1997; Abu-Eishah et al., 2000) and K-feldspar and gypsum (Wang et al., 2014a; Zhong et al., 2017). However, these methods are not widely used due to their respective shortcomings.