Micro- and nano-structured functional materials by polymer- aided self-assembly

Ph.DDOCTOR OF PHILOSOPH

Chemistry and interfacial mechanics of a phase change material on metal surfaces

Master'sMASTER OF SCIENC

In-place synthesis of Pt-modified brookite TiO2 micrometre-sized sensing elements via wet oxidation of Ti/Pt/Ti films on glass

In-place synthesis of Pt-modified brookite TiO2 micrometre-sized sensing elements via wet oxidation of Ti/Pt/Ti multilayers on glass Pt-modified anatase polymorph of TiO2 is one of the most widely reported oxides used for sensing. In contrast, there is much fewer published work on brookite polymorph of TiO2 (TiO2(B)) because of its smaller stability window. Here, we demonstrate a one-step process to synthesize in-place micrometer-sized Pt-modified TiO2(B) sensing elements. Ti/Pt/Ti multilayer films sputtered on glass substrates were selectively oxidized in aqueous hydrogen peroxide to form a gel. Upon thermal annealing gel films transformed into TiO2(B). Stability of TiO2(B) is attributed to diffusion of sodium ions from glass. Pt-TiO2(B) gas sensors exhibited shorter response time and higher current increase compared to similar devices utilizing anatase TiO2 (TiO2(A)). Sensor response of up to 6 × 105 was achieved in 4000 ppm hydrogen gas

Agar with embedded channels to study root growth

Abstract Agar have long been used as a growth media for plants. Here, we made agar media with embedded fluidic channels to study the effect of exposure to nutrient solution on root growth and pull-out force. Black Eye bean (Vigna Unguiculata) and Mung bean (Vigna Radiata) were used in this study due to their rapid root development. Agar media were fabricated using casting process with removable cores to form channels which were subsequently filled with nutrient solution. Upon germination, beans were transplanted onto the agar media and allowed to grow. Pull-out force was determined at 96, 120 and 144 h after germination by applying a force on the hypocotyl above the gel surface. The effect of nutrients was investigated by comparing corresponding data obtained from control plants which have not been exposed to nutrient solution. Pull-out force of Black Eye bean plantlets grown in agar with nutrient solution in channels was greater than those grown in gel without nutrients and was 110% greater after 144 h of germination. Pull-out force of Mung bean plantlets grown in agar with and without nutrient solution was similar. Tap root lengths of Black Eye bean and Mung Bean plantlets grown in agar with nutrient solution are shorter than those grown without nutrient.

Morphological investigations of self-assembled films from a pyridine -incorporated poly (p-phenylene)

10.1007/s10934-006-8023-4Journal of Porous Materials133315-317JPMA

Amphiphilic poly(p-phenylene)-driven multiscale assembly of fullerenes to nanowhiskers

10.1021/nn8001664ACS Nano271429-143