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Health and Safety Information
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Ceiling value [1,2-Dichlorobenzene] [1,4-Dichlorobenzene] [3,3'-Dichloro[1,1'-biphenyl]-4,4'-diamine]; levels as low as possible [CFC-12] [Ethylidene dichloride] [Ethylene dichloride] [Vinylidene chloride] [cis-1,2-Dichloroethylene] [trans-1,2-Dichloroethylene] [Refrigerant 21] [Methylene chloride] [Ethide] [2,4-D]; inhalable fraction [Propylene dichloride] [2,2-Dichloropropionic acid] [cis-1,3-Dichloropropylene] [trans-1,3-Dichloropropylene] [CFC-114] [Phosphoric acid, 2,2-dichloroethenyl dimethyl ester] [o-Phthalodinitrile]; inhalable fraction or vapor [m-Phthalodinitrile]; inhalable fraction & vapor inhalable fraction & vapor as total hydrocarbons [Bis(2-hydroxyethyl)amine]; inhalable fraction & vapor [N-Ethylethanamine] [2-(2-Butoxyethoxy)ethanol]; inhalable fraction & vapor [Ethyl ether] [Tetraethylmethane] [Vinylidene fluoride] [Bis(2,3-epoxypropyl) ether (DGE)] [N-Isopropyl-2-propanamine] [Isopropyl ether] [Methylal] [N,N-Dimethylethanamide] [N-Methylmethanamine] [Xylidine (unspecified isomer)]; all isomers [2,3-Xylidine] [2,4-Xylidine] [2,5-Xylidine] [2,6-Xylidine] [3,4-Xylidine] [3,5-Xylidine] [N,N-Dimethylbenzenamine] [Neohexane] [Diisopropyl] [Dimethylcarbamoyl chloride] [Methyl disulfide] [DMF]
Chemical Rocket Propellants
Published in D.P. Mishra, Fundamentals of Rocket Propulsion, 2017
Nitric acid (HNO3) is considered as an oxidizer in rocket engine, particularly when freezing point is not an issue. Generally, HNO3 is not used directly, rather nitric acid mixtures are being preferred in rocket engine. The nitric acid formulation most commonly used is the red fuming nitric acid (RFNA), which consists of HNO3, 5%–15% N2O4, and 1.5%–2.5% H2O. When the solution contains more than 86% HNO3, it is referred to as fuming nitric acid. The red color of RFNA is due to the presence of the nitrogen dioxide that is formed during the breaking down of N2O4. RFNA, along with other substances like amine nitrates, can be used as monopropellant. But it is usually used as bipropellant in rocket engine. Note that HNO3 is quite corrosive in nature. In order to reduce its corrosiveness, 0.4%–0.7% HF is added as a corrosion inhibitor and, hence, it is known as inhibited red-fuming nitric acid (IRFNA), which is being used in rocket engines. IRFNA along with aromatic amine fuels like aniline (C6H7N) and xylidine (C8H11N) had been used for missile applications. But IRFNA is quite toxic and volatile in nature as it contains large percentage of N2O4. In order to reduce its toxicity and volatility, less amount of N2O4 (less than 0.5%) is dissolved and it is known as white-fuming nitric acid (WFNA), which is considered as a safe and storable liquid oxidizer along with kerosene and hydrazine rocket fuel. Similarly, when 0.4%–0.7% HF is added to WFNA as a corrosion inhibitor, it is known as inhibited red-fuming nitric acid (IWFNA). Although WFNA has a somewhat less performance level as compared to the RFNA, it is used due to its nontoxic and low volatile nature. Nitric acid along with Aerozine has been used in the Titan family of launch vehicles and the second stage of the Delta II rocket engine. For tactical missiles, the US army had used IRFNA/UDMH. Note that Kosmos-3M is the most launched light orbital rocket with specific impulse of 291 s, in which IRFNA was used as an oxidizer along with UDMH fuel.
A novel basydiomycete isolated from mangrove swamps in the Colombian Caribbean shows promise in dye bioremediation
Published in Bioremediation Journal, 2022
Laura M. Jutinico-Shubach, Jesús D. Castaño, Tulio Juarez, Miguel Mariño, Javier Gómez-León, Lina M. Blandón
The effect of the carbon source, nitrogen source and inducer addition on laccase activity was evaluated using the one-factor-at-a-time method. For this purpose, the carbon source wheat bran, was substituted by other agro-industrial-wastes: corncob, banana peel and rice hulls (50 gL−1). The banana peel and corncob were washed with distilled water to remove impurities and dried at 60 °C for 3 days. The dried and sieved solid (size 300 μm) was used as a carbon source in the culture medium. The nitrogen source peptone, was replaced with ammonium sulfate, yeast extract and sodium nitrate (1.4 gL−1). On the other hand, the effect of different molecules reported as laccase activity inducers (Elisashvili et al. 2010) was evaluated. The compounds 2,5-xylidine, veratryl alcohol, vanillic acid (1 mM in 3% ethanol) and ethanol (3%) were added on the fourth day of growth. After addition, the flasks were incubated for eight days at 26 ± 3 °C in darkness. The supernatants were collected and evaluated as described above. ANOVA tests (p < 0.05) were run using the agricolae package (Mendiburu 2017) in R software (R version 4.0.3 (2020-10-10), R Foundation for statistical computing).
High dye removal capacity of Peniophora laxitexta immobilized in a combined support based on polyurethane foam and lignocellulosic substrates
Published in Environmental Technology, 2022
Leonardo Majul, Sonia Wirth, Laura Levin
To determine the expression patterns of laccase isoenzymes, the proteins in the supernatants of dye removal assays before the exposure to MG (T0) and after the third incubation cycle (C3) were separated by Native-PAGE and the activity was revealed by in-gel oxidation of DMP or decolorization of MG. In T0, two bands revealed the presence of two isozymes that were able to oxidize DMP but did not decolorize MG (Figure 5(A,B)). On the other hand, in the supernatants of the C3 cycle, the induction of a third form with higher apparent molecular weight, capable of oxidizing DMP and decolorize MG was observed (Figure 5(B)), suggesting that this soluble isoenzyme together with mycelium associated laccases could be the responsible for enzymatic dye removal. Dye presence also stimulated laccase production by other white-rot mushrooms [39], e.g. 2,5-xylidine enhanced the transcription and translation of lac1 gene in T. villosa [66] and lcc gene in T. versicolor [67]. This increase might be associated with the expression of new laccase isoforms with different substrate affinities and diverse capacities of dye decolorization [68–70]. Different laccase isoform patterns might be explained as well by the heterogeneous distribution of regulatory elements along the promoter regions of laccase genes that are activated by dyes. The presence of Xenobiotic Response Elements (XREs) in the promoter region of Pleurotus sajor-caju laccase genes corresponded with laccase isoenzyme expression in the presence of 2,5-xylidine [71], and also with the up regulation of transcripts matching laccase genes pox3 and pox4 in presence of RBBR [72]. This up regulation of genes with different amounts of regulatory elements was also seen in Trametes sp. AH28-2 in the presence of aromatic compounds [73].