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Nanotechnology-Enabled Next-Generation LED Lights
Published in Tuan Anh Nguyen, Ram K. Gupta, Nanotechnology for Light Pollution Reduction, 2023
Irfan Ayoub, Rishabh Sehgal, Vijay Kumar, Rakesh Sehgal, Hendrik C. Swart
This technique is most favorable for the synthesis of silicate and fluoride-based phosphor materials. Among the different available techniques, this one is known to be one of the most cost-effective as it does not necessitate any use of expensive and complicated instrumentation [56]. In this technique, the desired materials (host & dopant) are taken in the stoichiometric ratios and then mixed completely by forming a solution using deionized as solvent. The solution is then kept on a stirrer with a hotplate for the attainment of the transparency of the solution. In this method, ammonium hydroxide is used as a precipitating agent. After the addition of the precipitating agent, the solution is left for some time, till the attainment of proper precipitation. The solution is then filtered for separation of the desired material which is then followed by extensive washing and drying. This method proves to be effective for the incorporation of the rear-earth ions as dopants in the developed nanophosphors. For improving the properties, a modified version of this technique has been devised wherein the reaction is carried out in an inert environment. Some of the examples of the different phosphor materials developed by this method are Y2O2SO4:Eu3+ [57], K2MF6:Mn4+ (M = Ge, Si) [58], Ca3La (VO4)3:RE3+ (RE = Eu3+, Dy3+) [59] etc.
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
Weather conditions including wind directions and speed can play a major role on the scene of a hazardous materials incident. This role may be helpful or may cause negative issues when trying to mitigate an incident. High winds during a gas release may help disperse and dilute the gas to the point it is no longer harmful. On the other hand, lower winds may move a toxic or flammable cloud beyond the incident scene and place other areas in harm’s way. Sunny days can cause an increase in pressure in uninsulated containers and containers with dark colors, which absorb heat. An increase in pressure can cause a damaged portion of a tank to fail. Lighter colored tanks can reflect the heat of the sun. Leaks from tanks when it is raining can spread flammable liquids, which float on top of runoff water increasing the size of the incident scene. Water can also dissolve water-soluble gases and create another class of hazardous material, such as ammonium hydroxide from an ammonia plume. Ammonium hydroxide while not as hazardous as anhydrous ammonia; it is corrosive and can cause injury in contact with skin and corrode metal.
Laboratory Safety
Published in Frank R. Spellman, Kathern Welsh, Safe Work Practices for Wastewater Treatment Plants, 2018
Frank R. Spellman, Kathern Welsh
Bases such as sodium hydroxide, potassium hydroxide, and ammonium hydroxide quickly digest and corrode skin, clothing, and leather. Always handle them with extreme care. Use glassware or polyethylene containers. Ammonium hydroxide is extremely irritating to the eyes and respiratory system. When pouring ammonium hydroxide, use a fume hood and operate with a ventilation fan. In case of an accident involving bases, wash the affected area with copious amounts of water until the slippery feeling is eliminated. When handling a chlorine gas solution, also use a fume hood and avoid vapor inhalation. Secure the hood cover to prevent vapor escape. Ferric salts and ferric chloride are very corrosive to metals. Avoid bodily contact with them and wash off any residue immediately.Toxic Materials
Decellularized liver matrix-modified chitosan fibrous scaffold as a substrate for C3A hepatocyte culture
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Chaochen Zhao, Yang Li, Gongze Peng, Xiongxin Lei, Guifeng Zhang, Yi Gao
It is crucial to preserve the native ECM constituent and completely remove the cellular components during the decellularization process. Different decellularization protocols produce ECM with different components. Some decellularization methods, like harsh detergents, may remove most ECM components and damage the structure of ECM protein [28]. Because of that, the amount of decellularization agent should be reduced to limit side effects. In the present study, as a nonionic surfactant and a mild detergent, 1% Triton X-100 was utilized for decellularization. Triton X-100 is more appropriate for decellularization than other detergents, like sodium dodecyl sulphate (SDS), for it can remove DNA efficiently and preserve GAG in the meantime [29]. Furthermore, Triton X-100 permeabilizes the cell membranes, permitting the entry of ammonium hydroxide into cells for DNA denaturation. Addition of ammonium hydroxide can achieve a better decellularization. Histological analysis, GAG and DNA assessments of ECM confirmed the preservation of chief ECM constituent. The present decellularization method was safe and effective.
Demonstration of the MOEX Process Using Additive-Manufacturing-Fabricated Annular Centrifugal Contactors
Published in Solvent Extraction and Ion Exchange, 2020
Peter A. Kozak, Peter Tkac, Kent E. Wardle, M. Alex Brown, George F. Vandegrift
The details of the MOEX process are described by Tkac.[9] Briefly, the SGS is acidified to make ~0.3 M Mo in 5 M HCl solution. The acidification step removes ~75–80% of the potassium. Upon acidification, the Mo is extracted by 30% TBP (by volume) in tetrachloroethylene (TCE), while the potassium remains in the aqueous phase. The Mo is then stripped from the TBP by ammonium hydroxide. The evaporation of the Mo strip solution leads to formation of solid ammonium heptamolybdate (NH4)6Mo7O24, which can be directly reduced to Mo metal.[10] Typically, the Mo recovery yield (excluding reduction process) is 97.2 ± 2.4%. Due to the corrosive properties of HCl contained in the Mo feed and scrub solutions, traditional stainless-steel centrifugal contactors cannot be used with the MOEX process. Therefore, the results presented in this paper were obtained using AM-fabricated full-plastic centrifugal contactors tested using the MOEX process flow sheet (Figure 2).
PEGylated TiO2 nanoparticles mediated inhibition of cell migration via integrin beta 1
Published in Science and Technology of Advanced Materials, 2018
Qingqing Sun, Koki Kanehira, Akiyoshi Taniguchi
TiO2-PEG NPs were prepared as previously described [31]. In brief, 0.1 M titanium ethoxide in ethanol was mixed with 50% (v/v) acetonitrile and hydrolyzed for 60 min at room temperature. Ammonium hydroxide was then added to form a hydrolysis solution. The final concentrations of ammonium hydroxide ranged from 0.01 to 0.1% (w/v) and were dependent on the desired particle size. The hydrolysis solution was subsequently heated under reflux. The generated spherical TiO2 particles were then collected and finally adjusted to 20% (w/v) with methanol. Finally, a PEG co-polymer was coated on the surface of the spherical TiO2 NPs as described previously [32]. The morphology of NPs is displayed in Figure S1 (supplemental information). Besides that, the polydispersity index (PDI) of NPs was detected after dilution and stock in the cell culture medium for 24 h as follows: 0.1 (100 nm), 0.1 (200 nm), and 0.3 (300 nm).