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

#27
Feasibility of Solanum melongena Peelings Extract as a pH
Indicator
Joseph Angelo S. Chu, Kevin Thomas B. Go, Emmanuel Johann G. Peña III
ABSTRACT
This project aimed to develop a working pH indicator using the
anthocyanin-containing extract from the peels of Solanum melongena, more
commonly known as eggplant. The study dealt with extracting the anthocyanin of
the eggplant peels by boiling it in distilled water. The extract was then tested on
certain test chemicals, corresponding to certain pH levels (4, 7, and 10). During
the tests the extract was observed to exhibit a color change in each test solution
chemicals. Aside from the initially colored pH buffer solutions, other colorless
solutions like acetic acid (vinegar) and liquid detergent, which yielded different
color changes, were used to show that the extract did not just mix its color with
the test chemical. Success in this study will greatly help instruction involving pH
because of the simple procedure and accessibility and availability of eggplants.
#28
Mussel Shells as an Alternative Aggregate to Sand
In Concrete Making
Fatima R. Cipriano, Jestine A. Mariano, Pierre Emanuelle N. Santos
ABSTRACT
This project is about the replacement of sand as fine aggregate in class A
concrete mix. It aimed to find uses for waste mussel shells, and to provide a
cheap way for fishermen to build their houses. Specifically, it tested the effect of
the addition of the mussel shells to sand and cement mixture in class A concrete
mix.
The water, cement, and gravel (coarse aggregate) weight ratio were kept
constant with the standard mix. Only the sand component was changed to pure
crushed mussel shells procured from a wet market.
First, the mussel shells were pounded using mortar and pestle. The small
shells were placed in the Wiley Mill for further grinding. The cement to fine
aggregate to coarse aggregate ratio was then set to 1:2:3. A kilogram of cement,
four kilograms (4kg) of mussel shells, and six kilograms (6 kg) were brought to
the lab and were mixed in a half-bag mixer in order to yield three (3) samples.
However, the theoretical yield wasn’t achieved because some of the concrete mix
was stuck in the mixer. Two samples were made from the ingredients.
After 28 days, the samples were tested for their compressive strength and
unit weight. Their unit weights were near standard which is 2400 kg/ cm 3 .