The springs at Gypsum Hill and Colour Peak on Axel Heiberg Island in the Canadian Arctic originate from deep salt aquifers are among few known examples of cold thick permafrost Earth. discharge anoxic brines (7.5 to 15.8% salts), with a mean oxidoreduction potential -325 mV, contain high concentrations sulfate sulfide. We surveyed microbial diversity sediments seven by denaturing gradient gel electrophoresis (DGGE) analyzing clone libraries 16S rRNA genes amplified Bacteria Archaea-specific...

The saline springs of Gypsum Hill in the Canadian high Arctic are a rare example cold originating from deep groundwater and rising to surface through thick permafrost. heterotrophic bacteria autotrophic sulfur-oxidizing (up 40% total microbial community) isolated spring waters sediments were classified into four phyla (Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria) based on 16S rRNA gene analysis; isolates primarily psychrotolerant, salt-tolerant, facultative anaerobes. Some...

This study describes photolysis of the insensitive munition formulation IMX-101 [2,4-dinitroanisole (DNAN), NQ (nitroguanidine), and 3-nitro-1,2,4-triazol-5-one (NTO)] in aqueous solutions using a solar simulating photoreactor. Due to large variance water solubility three constituents DNAN (276 mg L-1), (5,000 NTO (16,642 two were prepared: one with low concentration (109.3 L-1) another high (2831 L-1). The degradation rate constants DNAN, NQ, (0.137, 0.075, 0.202 d-1, respectively) solution...

The identification of extant and, in some cases, extinct bacterial life is most convincingly and efficiently performed with modern high-resolution microscopy. Epifluorescence microscopy microbial autofluorescence or conjunction fluorescent dyes among the useful these techniques. We explored labeling imaging bacteria rock soil context situ detection for planetary exploration. goals were two-fold: to target non–Earth-centric biosignatures greatest possible sensitivity develop procedures...

Journal Article Microaerophilic degradation of hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX) by three Rhodococcus strains Get access M.E. Fuller, Fuller Shaw Environmental, Inc., Lawrenceville, NJ, USA Mark E. 17 Princess Road, NJ 08648, USA. E‐mail: mark.fuller@shawgrp.com Search for other works this author on: Oxford Academic Google Scholar N. Perreault, Perreault Biotechnology Research Institute, National Council Canada, Montreal, PQ, Canada J. Hawari Letters in Applied Microbiology,...

The perennial springs at Gypsum Hill (GH) and Colour Peak (CP), situated nearly 80 degrees N on Axel Heiberg Island in the Canadian high Arctic, are one of few known examples cold thick permafrost Earth. emanate from deep saline aquifers discharge anoxic brines rich both sulfide sulfate. Grey-coloured microbial streamers form during winter months snow-covered regions GH spring run-off channels (-1.3 C to 6.9 C, approximately 7.5% NaCl, 0-20 p.p.m. dissolved sulfide, 1 oxygen) but disappear...

Anaerobic transformation of the explosive RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) by microorganisms involves sequential reduction N-NO(2) to corresponding N-NO groups resulting in initial formation MNX (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine). is further reduced dinitroso (DNX) and trinitroso (TNX) derivatives. In this paper, we describe degradation TNX unusual cytochrome P450 XplA that mediates metabolism Rhodococcus rhodochrous strain 11Y. known degrade under aerobic...

Nitroguanidine (NQ) is an energetic material that used as a key ingredient of triple-base propellants and currently being considered TNT replacement in explosive formulations. NQ was efficiently degraded aerobic microcosms when carbon source added. persisted unamended or under anaerobic conditions. An NQ-degrading bacterium, Variovorax strain VC1, isolated from soil containing the sole nitrogen source. degradation inhibited presence more favorable nitrogen. Resting cells VC1 effectively (54...

N-Guanylurea-dinitramide (FOX-12) is a very insensitive energetic material intended to be used in the composition of next-generation munitions. To help predict environmental behavior and fate FOX-12, we conducted study determine its photodegradability biodegradability. When dissolved water, guanylurea-dinitramide salt, also named GUDN, dissociated instantly produce dinitramide moiety guanylurea, as demonstrated by high-performance liquid chromatography (HPLC) analysis. an aqueous solution...

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a cyclic nitramine explosive commonly used for military applications that responsible severe soil and groundwater contamination. In this study, Shewanella oneidensis MR-1 was shown to efficiently degrade RDX anaerobically (3.5 µmol·h(-1)·(g protein)(-1)) via two initial routes: (1) sequential N-NO(2) reductions the corresponding nitroso (N-NO) derivatives (94% of degradation) (2) denitration followed by ring cleavage. To identify genes...

The explosive 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) is of particular interest due to its extreme insensitivity impact, shock and heat, while providing a good detonation velocity. To determine fate under environmental conditions, TATB powder was irradiated with simulated sunlight and, in water, UV light at 254 nm. hydrolysis particles submerged neutral alkaline solutions also examined. We found that, by changing experimental conditions (e.g., source, mass physical state TATB), the...

Due to the emission of hazardous chemicals and heat, traditional smelting method used extract critical minerals from ore mine slag/tailings is considered bad for environment. An environmentally friendly procedure that can stabilize sulfur emissions waste without endangering environment bioleaching. In present study, sequential oxidative (Oxi) reductive (Red) bioleaching acid-pretreated copper smelter slag using iron-oxidizing/reducing Acidithiobacillus ferrooxidans was applied investigate...

Nanoenergetics has the potential to become next generation of explosives and propellants. Nano-explosives often show better performances in terms energy release, ignition mechanical properties compared their bulk counterparts. In addition monomolecular such as nano-TNT nano-RDX, diverse energetic nanocomposites have been developed, including nanometer-sized versions conventional thermites (nanothermites) those using carbon-based nanomaterials (e.g., fullerenes carbon nanotubes). While unique...

The photolysis of bis(1H-tetrazol-5-yl)amine (H2BTA) in water was carried out SolSim and Rayonet photochemical reactors equipped with solar simulating ultraviolet lamps, respectively. intermediary degradation products were monitored tentatively identified by liquid chromatography – mass spectrometry (LC–MS). A quadrupole time-of-flight spectrometer (QTOF) used to measure the mass-to-charge ratio (m/z) deprotonated molecular ions ([M H]−) using electrospray ionization negative mode (ESI-),...