Hydrolysis of Methylphosphonic Anhydride Solid to Methylphosphonic Acid Probed by Raman and Infrared Reflectance Spectroscopies

2021 ◽  
Author(s):  
Tanya L Myers ◽  
Danielle Saunders ◽  
James Szecsody ◽  
Russel Tonkyn ◽  
Kai-For Mo ◽  
...  
Keyword(s):  
Environmental Degradation ◽  
Methylphosphonic Acid ◽  
Infrared Reflectance ◽  
Organophosphorous Pesticides ◽  
Organophosphorous Compound ◽  
Hydrolysis Of

Much is still unknown about the mechanisms and rates of environmental degradation of organophosphorous pesticides and agents. In this study we focus on the degradation of one organophosphorous compound, namely...

THE ENZYMATIC HYDROLYSIS PRODUCTS OF SARIN

1956 ◽  
Vol 34 (1) ◽  
pp. 75-79 ◽  
Author(s):  
F. C. G. Hoskin
Keyword(s):  
Enzymatic Hydrolysis ◽  
Cholinesterase Inhibitor ◽  
Methylphosphonic Acid ◽  
Serum Enzyme ◽  
Rat Serum ◽  
Hydrolysis Products ◽  
Hydrolysis Of

The hydrolysis of the powerful cholinesterase inhibitor, sarin, by a rat serum enzyme leads almost exclusively to isopropyl methylphosphonic acid, neither methylphosphonic acid nor hydrogen methylphosphonofluoridate being formed. When isopropyl methylphosphonic acid is administered to the intact rat, it is excreted unchanged in the urine. It is inferred, therefore, that the metabolism of sarin by the intact rat would lead almost exclusively to isopropyl methylphosphonic acid.

Lanthanum ion catalysis of nucleophilic displacement reactions of monoesters of methyl phosphonic acid

1969 ◽  
Vol 47 (23) ◽  
pp. 4383-4387 ◽  
Author(s):  
R. J. Withey
Keyword(s):  
Aqueous Solution ◽  
Phosphonic Acid ◽  
Methylphosphonic Acid ◽  
Nucleophilic Displacement ◽  
Displacement Reactions ◽  
Lanthanum Ion ◽  
Rate Of Hydrolysis ◽  
Catalytic Effects ◽  
Hydrolysis Of

The catalytic effects of lanthanum ion on the rate of hydrolysis of p-nitrophenyl hydrogen methylphosphonate in aqueous solution at pH > 7.0 are reported. Increases in rate by a factor of about 3.6 × 104 have been observed. No such catalysis was found for diesters of methylphosphonic acid.

scholarly journals Hydrolysis of Dimethyl Methylphosphonate (DMMP) in Hot-Compressed Water

2020 ◽  
Author(s):  
Brian Pinkard ◽  
Shreyas Shetty ◽  
John Kramlich ◽  
Per G. Reinhall ◽  
Igor V. Novosselov
Keyword(s):  
Hydrolysis Rate ◽  
Methylphosphonic Acid ◽  
Practical Implementation ◽  
Reaction Products ◽  
Dimethyl Methylphosphonate ◽  
Exponential Factor ◽  
First Order ◽  
Pseudo First Order ◽  
Hot Compressed Water ◽  
Hydrolysis Of

<p>Dimethyl methylphosphonate (DMMP) is widely used as a chemical surrogate for G- and V-type nerve agents, exhibiting similar physiochemical properties, yet significantly lower toxicity. Continuous hydrolysis of DMMP in hot-compressed water is performed at temperatures from 200 to 300 °C, pressures of 20 and 30 MPa, and residence times from 30 to 80 s to evaluate the effects of pressure and temperature on reaction kinetics. DMMP hydrolysis is observed to follow pseudo-first-order reaction behavior, producing methylphosphonic acid and methanol as the only detectable reaction products. This is significant for the practical implementation of a continuous hydrothermal reactor for chemical warfare agent neutralization, as the process only yields stable, less-toxic compounds. Pressure has no discernible effect on the hydrolysis rate in compressed liquid water. Pseudo-first-order Arrhenius parameters are determined, with an activation energy of<i> </i>90.17±5.68<i> </i>kJ mol<sup>-1</sup> and a pre-exponential factor of 10<sup>7.51</sup><sup>±0.58</sup> s<sup>-1</sup>.<br></p>

Toxicity of Binary Chemical Munition Destruction Products: Methylphosphonic Acid, Methylphosphinic Acid, 2-Diisopropylaminoethanol, DF Neutralent, and QL Neutralent

2007 ◽  
Vol 26 (6) ◽  
pp. 503-512 ◽  
Author(s):  
Rebecca E. Watson ◽  
Ahmed M. Hafez ◽  
Jonathan N. Kremsky ◽  
George O. Bizzigotti
Keyword(s):  
Ames Test ◽  
Lethal Dose ◽  
Methylphosphonic Acid ◽  
Major Constituent ◽  
Toxicity Tests ◽  
Chemical Agent ◽  
Sprague Dawley ◽  
Ecotoxicity Tests ◽  
Good Laboratory ◽  
Hydrolysis Of

This paper reports the toxicity and environmental impact of neutralents produced from the hydrolysis of binary chemical agent precursor chemicals DF (methylphosphonic difluoride) and QL (2-[bis(1-methylethyl)amino]ethyl ethyl methylphosphonite). Following a literature review of the neutralent mixtures and constituents, basic toxicity tests were conducted to fill data gaps, including acute oral and dermal median lethal dose assays, the Ames mutagenicity test, and ecotoxicity tests. For methylphosphonic acid (MPA), a major constituent of DF neutralent, the acute oral LD50 in the Sprague-Dawley rat was measured at 1888 mg/kg, and the Ames test using typical tester strains of Salmonella typhimurium and Escherichia coli was negative. The 48-h LC50 values for pH-adjusted DF neutralent with Daphnia magna and Cyprinodon variegatus were >2500 mg/L and 1593 mg/L, respectively. The acute oral LD50 values in the rat for QL neutralent constituents methylphosphinic acid (MP) and 2-diisopropylaminoethanol (KB) were both determined to be 940 mg/kg, and the Ames test was negative for both. Good Laboratory Practice (GLP)-compliant ecotoxicity tests for MP and KB gave 48-h D. magna EC50 values of 6.8 mg/L and 83 mg/L, respectively. GLP-compliant 96-h C. variegatus assays on MP and KB gave LC50 values of 73 and 252 mg/L, respectively, and NOEC values of 22 and 108 mg/L. QL neutralent LD50 values for acute oral and dermal toxicity tests were both > 5000 mg/kg, and the 48-h LD50 values for D. magna and C. variegatus were 249 and 2500 mg/L, respectively. Using these data, the overall toxicity of the neutralents was assessed.

scholarly journals Hydrolysis of Dimethyl Methylphosphonate (DMMP) in Hot-Compressed Water

2020 ◽  
Author(s):  
Brian Pinkard ◽  
Shreyas Shetty ◽  
John Kramlich ◽  
Per G. Reinhall ◽  
Igor V. Novosselov
Keyword(s):  
Hydrolysis Rate ◽  
Methylphosphonic Acid ◽  
Practical Implementation ◽  
Reaction Products ◽  
Dimethyl Methylphosphonate ◽  
Exponential Factor ◽  
First Order ◽  
Pseudo First Order ◽  
Hot Compressed Water ◽  
Hydrolysis Of

<p>Dimethyl methylphosphonate (DMMP) is widely used as a chemical surrogate for G- and V-type nerve agents, exhibiting similar physiochemical properties, yet significantly lower toxicity. Continuous hydrolysis of DMMP in hot-compressed water is performed at temperatures from 200 to 300 °C, pressures of 20 and 30 MPa, and residence times from 30 to 80 s to evaluate the effects of pressure and temperature on reaction kinetics. DMMP hydrolysis is observed to follow pseudo-first-order reaction behavior, producing methylphosphonic acid and methanol as the only detectable reaction products. This is significant for the practical implementation of a continuous hydrothermal reactor for chemical warfare agent neutralization, as the process only yields stable, less-toxic compounds. Pressure has no discernible effect on the hydrolysis rate in compressed liquid water. Pseudo-first-order Arrhenius parameters are determined, with an activation energy of<i> </i>90.17±5.68<i> </i>kJ mol<sup>-1</sup> and a pre-exponential factor of 10<sup>7.51</sup><sup>±0.58</sup> s<sup>-1</sup>.<br></p>

THE ENZYMATIC HYDROLYSIS PRODUCTS OF SARIN

1956 ◽  
Vol 34 (1) ◽  
pp. 75-79 ◽  
Author(s):  
F. C. G. Hoskin
Keyword(s):  
Enzymatic Hydrolysis ◽  
Cholinesterase Inhibitor ◽  
Methylphosphonic Acid ◽  
Serum Enzyme ◽  
Rat Serum ◽  
Hydrolysis Products ◽  
Hydrolysis Of

The hydrolysis of the powerful cholinesterase inhibitor, sarin, by a rat serum enzyme leads almost exclusively to isopropyl methylphosphonic acid, neither methylphosphonic acid nor hydrogen methylphosphonofluoridate being formed. When isopropyl methylphosphonic acid is administered to the intact rat, it is excreted unchanged in the urine. It is inferred, therefore, that the metabolism of sarin by the intact rat would lead almost exclusively to isopropyl methylphosphonic acid.

Fine Structural Localization of Acyltransferases Involved in Lipid Synthesis in Intestinal Mucosa.

1970 ◽  
Vol 28 ◽  
pp. 54-55
Author(s):  
R. J. Barrnett ◽  
J. A. Higgins
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Lipid Synthesis ◽  
Mucosal Cell ◽  
Structural Localization ◽  
Morphological Studies ◽  
Mucosal Cells ◽  
Initial Appearance ◽  
Sh Group ◽  
Hydrolysis Of ◽  
Intestinal Mucosal Cells

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

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