2008 Analysis of the Geometry of Drilled Holes in Demolition ...

#49
The production of a bioplastic using plant starch
Claridge J Gamboa, Don David P Agudo, Maneka Kristia B Alemania
ABSTRACT
Two types of bioplastics using starch from potato and sweet potato,
respectively as base materials were produced to test its feasibility as a substitute
for Expanded Polystyrene. Expanded Polystyrene, also known as Styrofoam, is a
type of plastic created to be durable enough to perform many uses, but its
complete degradation into simpler compounds takes a hundred years. Past
researchers prove that some starch contain amylopectin that could be used to
create a material that could degrade in a shorter time.
To make the bioplastics, starch was blended with carrageenan, glycerol and
water. Each type of bioplastic had three starchcarrageenan-glycerol-water ratios
applied: 52:28:10:10, 40:40:10:10 and 28:52:10:10:. The mixtures were extruded
then cut into small pellets before undergoing thermal compaction at the DOST-
ITDI, materials Science Division in Taguig.
The resulting samples showed more properties of HDPE that that of
polystyrene. The average density of the samples in 30.8g/mL, which is greater
than the density of styrofoam. The two samples which contained sweet potato
starch and have more amount of carrageenan were completely destroyed in water
after 24 hours. All the samples did not completely degrade after 4 weeks of being
buried in soil, but some of the samples did break up into smaller pieces. The
sample which has the greatest amount of potato starch has the least density and
showed the least amount of changes in size and shape after being soaked in
water. This project was done to create a possible alternative for styrofoam food
packages which largely contribute to the mounting up of styrofoam on land-fills.
#50
Feasibility of Producing Ethanol from Zea mais leaves using
Trichoderma reesei, Trichoderma harzianum and
Saccharomyces cerevisiae
Juan Gabriel B. Gamboa, Paolo Raphael D. Legaspi, Miguel B. Tangangco
ABSTRACT
Rising oil prices and increasing environmental concern have resulted in
greater demand for ethanol, a fuel additive that lessens the amount of pollution
released by engines. Ethanol can be fermented from glucose, which can be
obtained from the break down of glycosidic bonds in cellulose. Commercial
production of ethanol uses corn kernels, corn cobs and sugar cane, which are rich
sources of glucose. The leaves of these plants are thrown away or burned. This