Abstract: For ages, activated carbon has been unarguably the most preferred material for chemical
warfare protective clothing by armies across the globe. Although the morphology in which
it is used has changed from granular form to fiber form, there has not been much change in
the chemical composition or functionality (ASZM-TEDA grade). In this paper we
investigate to find out if there is a possibility of replacement of the activated carbon by
other materials. Before we find the answer to this question, it is important to reason out
why replacement is thought of in the first place.
Activated carbon is a versatile material that brings with it several good qualities like large
surface area, adsorptive nature, fire-resistant, robustness and availability of aplenty. Some
of its disadvantages include heavy weight and low breathability (moist activated carbon
will adsorb oxygen from the environment causing breathing difficulties). One other
disadvantage which is often overlooked by the user is the disposal of the suits after usage.
Activated carbon merely adsorbs the nerve and mustard agents and once they become
saturated, they are classified as hazardous materials necessitating safe disposal. The used
wear is normally sent back to the supplier of manufacturer where it would be essentially
decontaminated by bleaching and then disposed by incineration or landfill. Thus, if there
is a material that can ensure breathability is of light weight and has the capacity to
decontaminate the adsorbed warfare agents in situ, it would be ideal for use in the
In this paper novel electrospun ceramic nanostructures are introduced which are capable
of reactive decontamination of nerve and mustard agents. The decontamination
efficiencies of the ceramic nanofibers are presented as tested against simulants of nerve
and mustard agents. Electrospinning was chosen as the fabrication method because it is a
simple traditional technique that is capable of manufacturing nano sized structures in a
large scale. Moreover, electrospun materials possess more activity due to their surface
charge density. The contribution of nano-size scale to the reactivity of the fibers is
shown. All these project the electrospun nanostructured ceramics as the best possible
substitutes to activated carbon.
Abstract: Boron carbide is one of the hardest materials known. The research on the synthesis of
nano-sized boron carbide is of great importance. RF plasma synthesis of B4C nanoparticle
was carried out by powder feeder using micro-sized commercial boron carbide
powder as the stating material. Different plasma energy and powder feeder probe position
was used to find out the optimum condition to achieve nanoparticles. Powders were
collected from Chamber 1, 2 and 3. fine particles can be achieved, but the decomposition
and oxidation of B4C powder during the high temperature plasma spray was detected.
Boron oxide was found in the sprayed powder, and the powder was purified by washing
and heat treatment. XRD, SEM and TEM was used to for characterization of the
Abstract: When one cut himself, it's amazing to watch how quickly the body acts to mend the wound.
Immediately, the body works to pull the skin around the cut back together. The concept of repair by
bleeding of enclosed functional agents serves as the biomimetric inspiration of synthetic self repair
systems. Such synthetic self repair systems are based on advancement in polymeric materials; the
process of human thrombosis is the inspiration for the application of self healing fibres within the
composite materials. Preliminary results based on flexural 3 point bend test on prepared samples have
shown the healed hollow fibre laminate has a healed strength increase of 47.6% compared to the
damaged baseline laminate. These results gave us confidence that there is a great potential to adopt
such self healing mechanism on actual composite parts like in aircraft’s composite structures.
Abstract: Carbon nanotubes (CNT) have been shown to enhance the engineering properties of
plastic fibers in ballistic-resistant garments enabling the garments to withstand very high impact
forces while remaining to be lightweight. Previous study shows that by reinforcing ultra high
molecular weight polyethylene (UHMWPE) fibers with a small amount of carbon nanotubes, the
fibers are simultaneously toughened and strengthened. In this paper, we study the mechanical
properties of carbon nanotube reinforced ultra high molecular weight polyethylene (UHMWPE) by
using micromechanics-based Mori-Tanaka model. Results show that the addition of small amount of
carbon nanotubes as reinforcement can substantially improve the mechanical properties of the
Abstract: Multi-walled carbon nanotube (MWNT) was filled into poly (ethylene terephthalate)
(PET) matrix and MWNT/PET composite was prepared by injection molding process. The
microstructure and electrical conductive property were investigated carefully. After injection
molding, the electrical conductivity of injected sample decreased sharply because of the orientation
of CNT due to strong shearing force. The electrical conductive network of CNT had been destroyed
after orientation of CNT. Because of the difference of shearing rate between the surface and the
body center during the injection molding process, a skin-core structure emerged. Near the surface,
the injected sample has higher degree of orientation of CNT and higher electrical resistance.
Abstract: Skutterudite materials have received great attention because their promising properties
for thermoelectric (TE) applications. Among the family of skutterudites, CoSb3 has been intensively
investigated due to its large electrical conductivity and Seebeck coefficient. However, its thermal
conductivity is too high to make it an effective TE material. Nanostructuring of CoSb3 has the
desirable effects of reducing its lattice thermal conductivity as the point imperfections or grain
boundaries can scatter phonons (heat carrier) more effectively than electrons (charge carrier). In this
study, nanostructured CoSb3 was synthesized by solvothermal routes using CoCl2·6H2O and SbCl3
as precursors dissolved in anhydrous ethanol with the reaction temperature kept at 240°C. In
addition to the CoSb3 phase, other Co-Sb compounds were also formed during the reaction process.
In this paper, we investigated the effects of processing parameters, such as concentration of
CoCl2·6H2O, SbCl3 and NaBH4 in ethanol and thermal duration of solvothermal synthesis, on the
yield of CoSb3 phase.
Abstract: Lead-based piezoceramic, such as lead zirconate titanate (PZT), is widely used because it
has excellent piezoelectric properties near the morphotropic phase boundary (MPB). However,
because of environmental issues associated with lead, the development of lead-free piezoceramics
has attracted much attention recently. Solid solution of (K,Na)NbO3 (KNN), (K,Na)TaO3 (KNT)
and LiNbO3 (LN) is one of the leading candidates. An MPB was formed at composition
[(K0.5Na0.5)0.97Li0.03](Nb0.8Ta0.2)O3(KNN-KNT-L0.03N). Its piezoelectric response has been
shown to be comparable to that of PZT system. However, complex texturing process is required to
achieve the desired property. In this project, we investigated the KNN-KNT-LN system using
conventional solid state reaction. The effects of increasing lithium, sintering process and the
addition of CuO on the sample structure and electrical properties were studied. Remanent
polarization of 28.39 μC/cm
was observed for the 0.1 wt% CuO added ceramic, which was sintered
under pressureless condition.
Abstract: PLZT9/65/35 thick films were prepared from the solution containing PVP360
(polyvinylpyrrolidone, with average molecular weight of 360000). With the solutions, the critical
thickness of a single PLZT layer could increase to ~624nm compared with 77nm-thick films
prepared without PVP360. Furthermore, by adding 20~35% excess of Pb to the precursor solutions,
the nano-porous rosette-like structures and a small amount of pyrochlore remnant, which were
found very common in the PVP-modified films, could be eliminated. 35% Pb excess was also found
to initiate liquid-phase sintering, leading to dense and crack-free films. The effect of Pb excess on
the rosette removal and densification behavior of the films was discussed. Moreover, the optical and
electrical properties of the PLZT films with 35% Pb excess were also studied.
Abstract: Thermoelectric (TE) materials are attracting renewed attention for clean energy
conversion. Reducing the dimension of materials to 2D/1D (e.g. thin film and nanowire) is one
major approach to achieve high figure of merit (ZT) in the existing TE materials system.
Electrodeposition has been widely used in fabricating various low dimensional TE materials.
However, electrodeposition behavior of CoSb3 skutterudites is rarely reported. In this work, we
report the co-deposition behavior of cobalt and antimony in citric based solutions by
electrodeposition. The effects of deposition potential and concentration of cobalt and antimony
containing precursors were studied. The focus of the study will be on the crystalline properties and
chemical composition of the deposited films.