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Zeolite
Published in Mihai V. Putz, New Frontiers in Nanochemistry, 2020
Adriana Urdă, Ioan-Cezar Marcu
In ion exchange applications, zeolites are used for water softening, radionuclide separations and wastewater treatments (Townsend & Coker, 2001). Large amounts of low Si/Al ratio zeolites (mainly A type) are used in detergent formulations for water softening, i.e., replacing their exchangeable cations (e.g., Na+) for Ca2+ and Mg2+ ions from water and reducing the environmental impact that previously used sodium triphosphate had. For the 90Sr2+ and 137Cs+ radionuclide separations from low- and medium-level nuclear waste, natural zeolites are of great interest due to their abundance and low cost, but synthetic ones are also highly efficient. They have to remove the nuclides in the presence of significant amounts of competing ions, such as Ca2+, Mg2+, Na+, etc.; therefore highly selective exchangers are needed. In the wastewater treatment, zeolites are used for the removal of ammonia and ammonium salts, but also heavy metal cations or other transition metal ions, in certain conditions (Townsend & Coker, 2001).
Organic Small-Molecule Materials for Organic Light-Emitting Diodes
Published in Zhigang Rick Li, Organic Light-Emitting Materials and Devices, 2017
Shijian Su, Norman Herron, Hong Meng
The metal salt of lithium phosphate (Li3PO4) [168] or sodium triphosphate (Na3PO4) [169] was deposited between the organic semiconductor and an Al cathode; the bilayer cathode enabled a device performance of OLEDs competitive to the benchmark cathode LiF/Al and increased the device lifetime. In addition, Zhang et al. reported the device with Alq3 doped with 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H[1] benzopyrano[6,7,8-ij]quinolizin-11-one as the EML and lithium cobalt oxide (LiCoO2) as the EIL showed promising efficiency (10.74 cd/A at 11V) and longer lifetime (2.8 times as much as LiF/Al control device). Lithium cobalt oxide was proved to be thermally decomposed in vacuum to form lithium oxide, which was responsible for the enhanced electron injection [170]. Siemund et al. first introduced the molecule sodium stearate (NaSt) as EIL in combination with the fluorescent polymer phenylene substituted poly(para-phenylenevinylene) (Ph-PPV) in OLEDs, the fabricated devices show current efficiencies up to 8.4 cd/A, indicating that the employed NaSt/Al bilayer cathode has adequate electron-injection capabilities in conjunction with Ph-PPV and, therefore, NaSt has the potential to become a nontoxic alternative to the widely-used alkali halide LiF [171].
Household and Personal Care Products: Cleaning up and Looking Good
Published in Richard J. Sundberg, The Chemical Century, 2017
The builder is a major constituent of dishwasher detergents and functions to sequester calcium ions and prevent deposition of calcium salts, either as CaCO3 or as salts of organic acids. The builders also function synergistically with the detergent’s surfactant action. Detergents without builders have much higher levels of surfactants. The most effective builder is sodium triphosphate, Na3P3O10. However, because phosphates are believed to contribute to eutrophication, their use is restricted in many jurisdictions. In the United States, the regulations are at the state and local level and are not consistent. European regulation also differs from country to country. Sodium triphosphate can be replaced by chelating carboxylates such as citrate and nitrilotriacetate. Recently, the use of zeolites and carboxylate polymers has become common. The zeolites function by ion exchange, adsorbing Ca2+ into the pores and exchanging Na+ into the water phase. Polyanionic materials such as carboxymethyl cellulose function by stabilizing emulsions. Dishwashing products also contain sodium silicates to provide alkalinity and function as an anticorrosion agent.
Electrochemical phosphorus release and recovery from wastewater sludge: A review
Published in Critical Reviews in Environmental Science and Technology, 2023
Zixuan Wang, Fubin Liu, Zhen He
Another anodic P release approach is the direct anode oxidation or the indirect generation of oxidizing radicals that could break down sludge NRP and then release ortho-P. This approach was studied only for the treatment of a specified NRP contaminant, and its performance of P release from wastewater sludge is yet to demonstrate (Lei et al., 2020; Zhang et al., 2020). NRP of various molecular structures, including hexa-meta phosphate, sodium triphosphate, beta-glycerol phosphate, phytic acid, and triethyl phosphate, were treated by direct anode oxidation and it was found that the organic NRPs released ortho-P faster than the inorganic NRPs (Mallick et al., 2021). A photoelectrocatalytic system equipped with a catalysis-doped anode was employed to generate hydroxyl radicals under an applied voltage of 3 V that completely oxidized 1 mM hypophosphite (H2PO2-) into ortho-P within 30 minutes (Zhang et al., 2020). However, anodic P release tends to mobilize heavy metals that coexist in the sludge, for example SSA can contain a high level of lead, copper, chromium, and cadmium (Ebbers et al., 2015b; Parés Viader et al., 2017b).
Characterization of the crystallographic properties of bamboo plants, natural and viscose fibers by X-ray diffraction method
Published in The Journal of The Textile Institute, 2021
Bahrum Prang Rocky, Amanda J. Thompson
This study was conducted on four bamboo species of two- to four-year-old plants that are abundantly available: Red Margin (Phyllostachys rubromarginata), Moso (Phyllostachys edulis/pubescens), Giant Gray (Phyllostachys nigra henon), and Bissetii (Phyllostachys Bissetii) were collected from Lewis Bamboo, Inc., Alabama, USA. Sodium hydroxide (NaOH) beads, sodium bicarbonate (NaHCO3), sodium silicate (Na2SiO3), sodium triphosphate (85% Na5P3O10), and sodium sulfite (Na2SO3) were purchased from Sigma-Aldrich, USA. Hydrogen peroxide/H2O2 (30% w/w) was provided by VWR International, LLC, USA. A scouring agent (Consoscour GSRM), bleaching agent (Consobleach CIL), and penetrating agent (Consamine JDA) were purchased from Consos, Inc., USA, and fabric softener was collected from a local Publix Super Market, Inc., USA.
Development of chitosan/gelatin hydrogels incorporation of biphasic calcium phosphate nanoparticles for bone tissue engineering
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Lei Nie, Qiaoyun Wu, Haiyue Long, Kehui Hu, Pei Li, Can Wang, Meng Sun, Jing Dong, Xiaoyan Wei, Jinping Suo, Dangling Hua, Shiliang Liu, Hongyu Yuan, Shoufeng Yang
The CGB scaffolds were produced by using a cycled freeze-thawing technique based on both physical cross-linking and chemical cross-linking. In brief, a 2 wt % chitosan (CS) solution prepared by dissolving CS in 1% acetic acid solution. After that, gelatin (Gel) and BCP-NPs were added into CS solution, the mixture was stirred at room temperature for 24 h. Then the mixture was poured into a 48-hole polystyrene plate and degassed for 1 h by using a vacuum oven at room temperature. The samples were quenched at −20 °C for 24 h, and then thawed at 25 °C for 2 h, 3 freeze-thawing cycles were carried out. Then, the samples were dried by using a freeze-drying machine for 72 h. Finally, the dried samples were again cross-linked through immersing into a 2.5% sodium triphosphate solution for 3 h. Subsequently, the samples were washed with Millipore water for 10 min 3 times, then, freeze-drying was performed to obtain CGB scaffolds. The prepared scaffold was called Sabc, where S is scaffold, and a, b, c was the mass ratio of CS, Gel, and BCP-NPs (i.e. S111). In this article, S211, S212, S213, S214, S111, and S312 were prepared, as shown in Figure 1 and Table 1.