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Common Sense Emergency Response
Published in Robert A. Burke, Common Sense Emergency Response, 2020
Making illegal drugs does not require the sophistication, knowledge, or equipment necessary to manufacture chemical and biological terrorism agents. Not all chemicals associated with illegal drug manufacture are regulated and many are available from local merchants such as pharmacies, hardware stores, supermarkets, discount and convenience stores, and agricultural cooperatives. Transactions that occur in these locations involving large purchases of suspected chemicals should be reported to law enforcement. Even better, retailers should be taught to limit the amounts of materials sold, making the drug lab operators work harder to obtain the raw materials needed for drug manufacture. Though not consistent in all locations, some chemicals which may be used in illegal drug manufacture are regulated by government agencies. Manufacturers, distributors, and retailers should be aware of precursor chemicals used for illegal drug production.
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Making illegal drugs does not require the sophistication, knowledge or equipment necessary to manufacture chemical and biological terrorist agents. Not all chemicals associated with illegal drug manufacture are regulated, and many are available from local merchants such as pharmacies, hardware stores, supermarkets, discount and convenience stores and agricultural cooperatives. Transactions that occur in these locations involving large purchases of suspected chemicals should be reported to law enforcement. Even better, retailers should be taught to limit the amounts of materials sold, making the drug lab operators work harder to obtain the raw materials needed for drug manufacture. Though not consistent in all locations, some chemicals that may be used in illegal drug manufacture are regulated by government agencies. Manufacturers, distributors and retailers should be aware of precursor chemicals used for illegal drug production.
Restricted substances for textiles
Published in Textile Progress, 2022
Arun Kumar Patra, Siva Rama Kumar Pariti
Bisphenols are precursor chemicals used along with other chemicals for making of plastic articles such as polyvinyl chloride (PVC) and polycarbonates (http://www.hbmreu.eu/the-substances/bisphenols). They are also used in manufacturing epoxy resins and thermal paper. In plastics they are often used for hardening of the material. Depending on their chemical structure, this group of compounds can function as flame retardants, UV stabilizers, pH indicators or as a developer in thermal printing. Chemically, bisphenols are a group of compounds with two hydroxyphenyl functionalities. Most of them are diphenylmethane-based and are referred to as Bisphenol A. The other types of Bisphenols are with suffixes, S, F, AF, P and M, the structures of some of which are given below (http://en.wikipedia.org/wiki/Bisphenol) (Figure 8).
Biogas potential determination and production optimisation through optimal substrate ratio feeding in co-digestion of water hyacinth, municipal solid waste and cow dung
Published in Biofuels, 2022
Tawanda Kunatsa, Lijun Zhang, Xiaohua Xia
Anaerobic digestion is an efficient and low cost technology for waste management that yields biogas – a high value biofuel. A more or less similar approach would be to use the same wastes and technology targeting the precursor chemicals such as carboxylic acids [38,72]. These chemicals would generate a lot of revenue but their demand and market is less than that of biogas. Proper management and handling of the produced biogas is key to mantaining the benefits of reduced GHG emissions. The digester has to be completely leak proof and the digestate slurry storage facilities have to be always covered to avoid the escaping of and can be captured and used on site or channeled towards other beneficial uses such production of chemicals among others. Small scale biogas plants come with high costs as such biogas plants have to be operated at large scale to achieve benefits of reduced operational costs and matching in competitiveness with convenional liquid petroleum gas and natural gas.
Effect of Cu and Mn doping on optical properties of ZnS:Cu,Mn nanoparticles synthesized by the hydrothermal technique
Published in Journal of Sulfur Chemistry, 2022
In the last decade, ZnS nanoparticles (NPs) received extensive research attention because they are promising in scintillators, quantum dots, electro-optical, photocatalytic applications, and the treatment of cancer [1–4]. The excellent luminescent properties of Cu and Mn co-doped ZnS crystals play a significant role in electroluminescence [5–7], mechano-luminescence [8–10], white LEDs [11,12], and fluorescent sensor devices [13–17]. Co-doping of Cu and Mn can reduce the emission of blue light and enhance the green emission [18]. The emission light color of Cu and Mn co-doped ZnS crystals is closely related to the concentration of Cu and Mn ions and the synthesis technology because doping ions can change the energy bandgap of ZnS and form luminescence centers with different energy levels [19–21]. Therefore, various techniques synthesized doped ZnS NPs and most of them were based on wet chemical techniques [22–27]. Hydrothermal techniques become popular because of their low cost, simple preparation of materials, and environment-friendliness. On the other hand, the temperature, pressure, reaction time, precursor chemicals, and solvent influence the final product’s structure, morphology, and optical properties.