Aromatic Hydrocarbon Degrading Phyllosphere Fungi

Ambient air contains high amounts of potentially genotoxic and carcinogenic aromatichydrocarbons (AH) that originate from the petroleum related activities and coal refiningprocesses. The potential of phyllosphere organisms to oxidize these compounds into nontoxicforms has been investigated in some recent studies. This study was carried out to investigatethe presence of aromatic hydrocarbon degrading fungi in the phyllosphere of Ixora sp.,Amaranth sp., Hibiscus sp. and Ervatamia sp. which are common on roadsides close to the oilrefinery at Sapugaskanda and in several urban areas having high level of vehicular emission.Their ability to degrade the AHs phenanthrene, naphthalene, xylene and toluene wasinvestigated.Leaf samples of the four plant species were collected from five areas namely Kollonnawa,Sapugaskanda, Orugodawattha, Panchikawattha and Maradana. Then Phyllosphere fungiwere isolated into pure cultures on Czapek-Dox medium using pour plate method andidentified up to the genus level. Plate assays and spectrophotometric analysis were used toevaluate phenanthrene, naphthalene, xylene and toluene degradation ability of them as thesole source of carbon. The best fungal AH degraders were selected for furthercharacterization and identification.Isolated phyllosphere fungi, Penicillium spp, Aspergillus spp and Trichoderma spp were ableto degrade phenanthrene, naphthalene, toluene and xylene. Penicillium janthinellum wasfound to be the most effective in degrading naphthalene and phenanthrene with 98.85% and84.83% efficiency respectively. Moreover, Aspergillus niger has the highest toluenedegradation ability. The best xylene degrader; Aspergillus flavus, utilised 57.35% of xylenein the medium. Initial experiments indicated that the highest degradation of aromatichydrocarbons occurs after seven days. Therefore, in all these experiments, isolated fungalspp. were incubated for seven days in media supplemented with aromatic hydrocarbons.While traditional chemical and physical remediation techniques are currently becoming lesseffective from environmental and economical point of view, there is an increasing interest inbioremediation. According to the finding of the present investigation Penicillium spp. andAspergillus spp. are having the potential to be used in effective bioremediation strategies inthe removal of AH. Their ability to degrade these compounds while surviving underenvironmental stresses makes them suitable candidates for bioremediation.

Rapid incorporation of carbon from ectomycorrhizal mycelial necromass into soil fungal communities

Peer reviewedPublisher PD

Macromolecules in the Bayer Process

This is the publisher's version, also available electronically from http://www.degruyter.com/view/j/revce.2003.19.5/revce.2003.19.5.431/revce.2003.19.5.431.xml.See article for abstract

Surfactant-mediated and morphology-controlled nanostructured LiFePO4/carbon composite as a promising cathode material for Li-ion batteries

The synthesis of morphology-controlled carbon-coated nanostructured LiFePO4 (LFP/Carbon) cathode materials by surfactant-assisted hydrothermal method using block copolymers is reported. The resulting nanocrystalline high surface area materials were coated with carbon and designated as LFP/C123 and LFP/C311. All the materials were systematically characterized by various analytical, spectroscopic and imaging techniques. The reverse structure of the surfactant Pluronic® 31R1 (PPO-PEO-PPO) in comparison to Pluronic® P123 (PEO-PPO-PEO) played a vital role in controlling the particle size and morphology which in turn ameliorate the electrochemical performance in terms of reversible specific capacity (163 mAhg 1 and 140 mAhg 1 at 0.1 C for LFP/C311 and LFP/ C123, respectively). In addition, LFP/C311 demonstrated excellent electrochemical performance including lower charge transfer resistance (146.3 Ω) and excellent cycling stability (95% capacity retention at 1 C after 100 cycles) and high rate capability (163.2 mAhg 1 at 0.1 C; 147.1 mAhg 1 at 1 C). The better performance of the former is attributed to LFP nanoparticles (< 50 nm) with a specific spindle-shaped morphology. Further, we have also evaluated the electrode performance with the use of both PVDF and CMC binders employed for the electrode fabrication

Scaling-up ultrasonic vibration assisted additive manufacturing to build 316 L 3 m3 waste container flange

Directed-energy deposition is a 3D printing method that uses a focused energy source, such as a plasma arc, laser, or electron beam to melt a material that is simultaneously deposited by a nozzle. As with other additive manufacturing processes, this technology is used to add material to existing components, for repairs, or to build new parts. Direct-energy deposition additive manufacturing techniques have gained much attention from the industry to build/repair in-service components. However, this process undergoes complex dynamics of melting and solidification raising challenges to the effective control of grain structure causing potential structural failure. This research study was conducted to investigate the potential of using high-intensity ultrasonic to control the solidification process and scaling up the system to manufacture large components. From the feasibility study, it was noted that ultrasonic can assist in the refinement of the grain structure and also reduce anomalies such as porosities. Under the feasibility study, a range of frequencies and power configurations were considered to ease the scale-up of the system. Based on the studied ultrasonic configurations, the 40 kHz 60 W configuration was finalized to use in the scale-up. It was also noted the reduction of hot cracks in the ultrasonic-assisted additive manufacturing due to the constitutional supercooling during solidification by lowering the temperature gradient in the bulk of the melt pool. Furthermore, it was also noted that the grain orientation is perpendicular to the direction of vibration which potentially can be used to control the orientation of the grains as required. This new finding provides new applications to exploit the ultrasonic-assisted additive manufacturing process