A Na 3 V 2 (PO 4 ) 3 /C cathode synthesized by a polyol-assisted pyrosynthetic reaction and subsequent sintering delivered a discharge capacity of 235 mA h g À1 , corresponding to an extraction of 4 Na per formula with steady capacity retention and impressive rate capabilities that maintain 56% of theoretical capacity at 2.67 C.

A manganese dioxide (g-MnO 2 ) cathode was prepared by a simple ambient temperature redox reaction method for Na-ion batteries. The X-ray diffraction (XRD) pattern of the as-prepared sample annealed to low-temperatures ($200 C) revealed diffraction peaks confined to the orthorhombic phase of g-MnO 2 .The particle morphology of the sample, as revealed by the electron microscopy studies, was comprised of aggregated nanowire crystallites with diameters and lengths in the range of 2-3 and 25-40 nm, respectively. From the N 2 adsorption and Brunauer Emmett Teller (BET) studies, the average pore diameter and the surface area of the annealed g-MnO 2 was determined to be 3.77 nm and 148 m 2 g À1 respectively and thereby the mesoporous sample characteristics were confirmed. When employed in a Na/MnO 2 cell, the mesoporous g-MnO 2 cathode registered initial discharge and charge capacities of 234 and 233 mA h g À1 with almost 100% Coulombic efficiency. Although gradual capacity fading was observed on successive electrochemical cycling, the present study confirms the use of mesoporous electrodes as suitable Na-intercalation/de-intercalation hosts for emerging sodium battery applications.

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Particulate matters (PMs) such as PM10 and PM2.5 were collected at a bus stop and were analyzed using pyrolysis-gas chromatography/mass spectrometry to identify organic polymeric materials in them. The major pyrolysis products of the PM samples were isoprene, toluene, styrene, dipentene, and 1-alkenes. The pyrolysis products generated from the PM samples were identified using reference polymeric samples such as common rubbers (natural rubber, butadiene rubber, and styrene-butadiene rubber), common plastics (polyethylene, polypropylene, polystyrene, and poly(ethylene terephthalate)), plant-related components (bark, wood, and leaf), and bitumen. The major sources of the principal polymeric materials in the PM samples were found to be the abrasion of the tire tread and asphalt pavement, plant-related components, and lint from polyester fabric. The particles produced by the abrasion of the tire tread and asphalt pavement on the road were non-exhaustive sources, while the plant-related components and lint from polyester fabric were inflowed from the outside.

Tire wear particle has been considered as one of environmental pollution sources and its sizes are widely ranged from PM 2.5 to several hundred micrometer (μm). A bus tire tread is generally composed of NR and BR. In the present work, difference in the rubber compositions of wear particles of a model bus tire tread compound (NR/BR = 80/20) depending