Undergraduate Theses
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Item Determination of instrument detection limit and method detection limit of Varian 55B flame atomic absorption spectrometer for cadmium, chromium, copper, iron, lead, manganese and zinc using sips-10 and manual sample introduction methodsCalawigan, Roland Joseph C. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2009-04)Determination of detection limits is an essential measure of performance for a quantitative laboratory, method or analyst. In this study, the Instrument Detection Limit (IDL) and Method Detection Limit (MDL) of F-AAS Varian 55B for cadmium, chromium, copper, iron, lead, manganese and zinc were determined using the SIPS-10 and manual sample introduction methods. For IDL determinations, EPA’s SW-846 method (Test Methods for Evaluating Solid Waste and Physical/Chemical Methods) was employed for both sample introduction methods where deionized water was analyzed for twenty times for three non-consecutive days. MDL determinations were done based on the definition given by the United States Code of Federal Regulations (40 CFR part 136, Appendix B - Definition and Procedure for the Determination of the Method Detection Limit). In this procedure, MDLs were estimated by calculating the standard deviation from the analysis of a standard solution containing the analyte with a concentration determined from the estimated detection limit, which was also analyzed for twenty times. Results showed that for the determination of IDL, all of the elements have lower values (Cd 0.000887 mg/L, Cr 0.00435 mg/L, Cu 0.000128 mg/L, Fe 0.000816 mg/L, Pb 0.000742 mg/L, Mn 0.000985 mg/L, Zn 0.000585 mg/L) for the manual method than the SIPS-10 method (Cd 0.00399 mg/L, Cr 0.0150 mg/L, Cu 0.00222 mg/L, Fe 0.00913 mg/L, Pb 0.0217 mg/L, Mn 0.00132 mg/L, Zn 0.00445 mg/L). For MDL, the results showed variations for both the two sample introduction methods. The MDL values for cadmium, chromium, copper, iron, lead, manganese and zinc are 0.0374 mg/L, 0.0235 mg/L, 0.00203 mg/L, 0.0197 mg/L, 0.0805 mg/L, 0.00325 mg/L and 0.00686 mg/L in the manual method, respectively and 0.0101 mg/L, 0.0429 mg/L, 0.00280 mg/L, 0.0186 mg/L, 0.19 7 mg/L, 0.00312 mg/L and 0.0103 mg/L in the SIPS-10 method, respectively. Both methods have comparable precision for copper, iron, manganese and zinc determinations while SIPS-10 method is more precise for cadmium, chromium, and lead analysis.Item Comparative study of trace metals and common impurities of table salt produced in Leganes, Iloilo and Tibiao, AntiqueCalawag, Jerolet E. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2000-10)Trace metals such as cadmium (Cd), chromium (Cr) and lead (Pb) as well as the common impurities in salt like magnesium (Mg), calcium (Ca), sulfate, moisture, matter insoluble in water (MIW) and matter insoluble in acid (MIA) were analyzed using spectrophotometric (Flame Atomic Absorption &UV-vis Spectrophotometers) and gravimetric methods. Results showed that percentage concentrations of magnesium and calcium were significantly higher in sample A (Tibiao table salt) than in sample B (Leganes table salt) at 1- percent level of confidence. The percentage concentrations of MIW, MIA, moisture and sulfate were significantly higher in sample B than in sample A. Results of Uv-vis absorption spectroscopy indicated that both chromium and cadmium were absent in both samples while the lead concentrations in samples A and B were 10.9190 and 11.4831 ppm respectively. At 5% level of probability, the lead concentrations of both samples did not differ from each other. Using another technique of analyzing trace metals, the flame atomic absorption spectroscopy based on flame atomization, different results were obtained. Lead concentration in samples A and B were 6.4874 and 9.4977-ppm salt respectively. At 5 % level of probability, sample B had higher lead concentration than in sample A. The lead concentrations in both samples were all higher than 0.015 ppm, the allowable maximum limit of lead in water, or any drinks. The over-all results showed that sample B had higher contaminants than in sample A.Item Knowledge on birth control methods among married males and females in a rural communityCalaguing, Mary Jean C. (Division of Social Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1998-03)This is a study on the knowledge of birth control methods among married males and females in a rural community. The study sought to 1) describe the overall knowledge of married males and females regarding birth control methods; 2) know the common birth control method known and used by married males and females; 3) know the different sources of knowledge on birth control methods and 4) to find out if there is a relationship between awareness and use of birth control methods. The study was conducted in Brgy. Buga, Leon, Iloilo. The respondents of the study are 45 married males and 45 married females. The instrument used was the interview schedule. The hypothesis was analyzed using the Linear Regression Test. Based on the findings, it was concluded that for married males and females in Brgy. Buga, Leon, Iloilo, the females are more aware of the different kinds .of birth control methods and its proper use. The common birth control known by most females is the pill, and it is also the most used method. For the males, the common birth control method known is the condom, while the most practiced method in the rhythm or calendar method. The primary source of knowledge or information on birth control methods is the barangay health center. Knowledge is an important factor in determining the use of birth control methods, however there are some factors that may affect the use of birth control methods. The study found out that there is no significant relationship between the awareness of birth control methods and use of birth control methods.Item Family characteristics related to malnutrition among preschool childrenCajilo, Ma. Donna C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)This is a co-relational study of family characteristics related to malnutrition among preschool children. It aimed to: 1.) find out if there is a relationship between family size and malnutrition among preschool children, 2.) find out if there is a relationship between birth spacing and malnutrition among preschool children, and 3.) find out if there is a relationship between mother’s work and malnutrition among preschool children. The study used interview guide to gather data. It utilizes materials from books, journals, and magazines. There were 30 respondents. These were the mothers of the identified 2nd and 3rd degree malnourished preschool children of Barangay Pitogo, San Joaquin, Iloilo. The researcher utilized the entire population of the mothers of the identified 2nd and 3rd degree malnourished preschool children because there were 30 only. The researcher didn’t include the mothers of the 1st degree malnourished preschool children due to fact that nutritional status of the child easily shifts to normal condition, therefore, data gathered maybe true for a short period of time and is not reliable for further study. The data was analyzed using frequency counts, percentages, and the chi-square test for independence. The study found out that: 1) there is no significant relationship between family size and malnutrition among preschool children, 2.) There is no significant relationship between birth spacing and malnutrition among preschool children, and 3.) there is no significant relationship between mother's work and malnutrition among preschool children.Item Panghunahuna sa kaugalingon: Traits, strivings, happiness and religious orientation in the lens of the five-factor modelCajilig, Veni Grace S. (Division of Social Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2017-06)The influence of personality traits, strivings, happiness, and religious orientation on self-concept were studied on 101 women who live within Iloilo city and who subscribe to a folk healer, specifically to a manughilot. Levene’s test indicated that the sample was homogeneous. Respondents were made to answer a battery of tests, namely International Personality Item Pool - NEO - 120, Religious Orientation Scale, Oxford Happiness Questionnaire, Self-concept Clarity Scale, and Personal Striving Checklist. Cronbach alpha was measured for the reliability. Moreover, validity of the scales were measured using Pearson product-moment correlation for both convergent and divergent. An interview was also conducted among five respondents wherein the qualification was based on the number of consultation visits with the manughilot, the highest and lowest were chosen. Using the Multiple Analysis of Variance, the four aforementioned variables did not significantly differentiate self-concept. The results of this study run contrary to the hypotheses and framework.Item Processing of sweet potato (Ipomoea Batatas var Bnas) into flour for bread makingCajilig, Ma. Madeline R. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 1984-04)Sweet potatoes of Bnas variety were processed into flour and its chemical composition such as moisture, fat, ash, crude fiber, protein and carbohydrates content were analyzed. Sweet potato flour has approximately 12.41% protein and an average value of 76.7% carbohydrates. The sweet potato flour was used as wheat flour extender where "pan de sal” was the test bread prepared from 50%, 40% and 30% formulation of sweet potato flour and wheat flour. These three formulations were compared with the control sample made of 100% wheat flour. A straight dough method was used in the preparation of the samples. Sensory evaluation test revealed that "pan de sal” was acceptable in all levels of substitution at 5% level of significance. This would mean that 50%, 40% and 30% sweet potato flour substitution is possible. It was also found that the samples with sweet potato flour produces more yield of "pan de sal” compared to the control sample. The cost involved in the control is considerably higher than the experimental samples.Item Toxicity of the aqueous leaf extract of datilis (Muntingia calabura) on the fry and fingerling of Oreochromis niloticusCagampang, Ma. Hazel C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-08)A 96-hour static bioassay on the effects datilis (Muntingia calabura) leaf extract on the fry and fingerlings of Oreochromis niloticus was conducted to determine the Average Median Lethal Concentration (LC50) of datilis (Muntingia calabura) leaf extract on the fry and fingerlings of Oreochromis niloticus and to describe the behavioral responses of the fish to the extract. The assay consisted of six treatments: 0, 12.5, 25, 50, 100, and 200 ppm concentrations of the extract. Physico-chemical conditions (e.g. temperature, pH, salinity, dissolved oxygen, ammonia, nitrite, and hardness level of water) were monitored. Results showed that the average LC50 at the 12, and 24- hour period of the extract in fingerlings (128.61 and 92.37 ppm) were significantly higher (P<0.05) than in the fry (65.45, and 60,99) respectively. Mortality was higher at higher concentrations than at lower concentrations of the extract. Highest mortality was in 200 ppm followed by 100 ppm, then 50 ppm. No death occurred in 0, 12.5 and 25 ppm concentrations of the extract. Mortality was also significantly higher (P<0.05) in fingerlings than in fry. The fish, exhibited avoidance - response reaction and loss of equilibrium. Possibly, the death and unusual behavior manifested by the fish may be due to saponins present in the extract. Physico—chemical conditions were within the tolerable range for the fish hence, these may not have contributed to the death of fish. This study provides preliminary data on the toxic effects of the aqueous leaf extract of datilis on the fry and fingerlings of ?Oreochromis niloticus.Item A preliminary study on the average yield of crude capsaicin from common varieties of Capsicum frutescens L. at two stages (Young and mature) using three extracting solventCadornigara, Ma. Sylvia C. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 1998)Crude capsaicin content of the air dried and homogenized plant material of the three varieties of Capsicum frutescens L. namely cayenne, tobasco and ‘kitikot’ were determined using diethyl ether, 99.5 % ethanol and 1.0N NaOH as extracting reagents. Statistical analysis showed no significant difference on the average percent yield of crude capsaicin on the three varieties of Capsicum frutescens L. using similar extracting solvent, but a significantly higher yield of crude capsaicin was found with 99.5% ethanol and 1.0N NaOH. Through thin layer chromatography the major components of the extracts identified could probably be capsaicinoids (Rf 15-17), carotenoids (only in 99.5% ethanol, Rf 96-97), and capsanthin (Rf 27-29) using n-hexane-acetone.Item Spontaneous formation of silver nanoparticles in humid acid-rich water of Santa Barbara, IloiloCadelina, Mary Dored Ann D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Humic acid (HA) - rich water of Sta. Barbara, Iloilo is successful in acting as a reducing and capping agent in the synthesis of silver nanoparticles (AgNPs). UV-Visible spectroscopy was used to determine the effect of irradiation time, varying HA and AgNO3 concentration, and electrolyte addition. Furthermore, the bactericidal efficacy of AgNPs was evaluated using broth microdilution method. Measurement of AgNPs was done using transmission electron microscopy (TEM). Lower irradiation time (10- 40 min) shows an increasing absorbance trend. However, absorbance decreased and showed bathochromic shifts when irradiated at longer times (50-60 min). AgNP formulations of 40 ppm HA with 4 mM AgNO3 and 50 ppm HA with 4 mM AgNO3 showed the highest peak intensity for varying AgNO3 and HA concentration, respectively. These results were found in both irradiated and un-irradiated samples. Aggregation occurred upon the addition of 50 mM, 100 mM, and 500 mM NaCl but was more prominent at 500 mM NaCl. Dialyzed and un-dialyzed AgNPs have bactericidal activity. However, un-dialyzed AgNP was a more effective treatment because it showed a bactericidal activity up to 1:16 dilution for both Staphylococcus aureus and Escherichia coli as compared to the dialyzed AgNPs which showed a bactericidal activity up to 1:4 for S. aureus and 1:8 for E. coli. The dialyzed AgNPs are polydispersed but were mostly small with sizes less than 10 nm based on the TEM image.Item Heavy metals (Cr, Cu, Pb, and Zn) concentrations of road-deposited sediments within six public plazas in Iloilo CityCaceres, Rizza Daphet E. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2011-04)Contamination from overland transportation is an unavoidable result of urbanization. Cr, Cu, Pb, and Zn arc common heavy metals introduced to the environment by transportation. Road-deposited sediment (RDS) samples were collected from six public plazas (Villa Plaza, Molo Plaza, Mandurriao Plaza, Plaza Libertad, Lapaz Plaza and Jaro Plaza) in Iloilo City from March 2010 to May 2010. 0.5M HC1 was used as extractant and heavy metals (Cr, Cu, Pb, and Zn) concentrations were determined using Flame Atomic Absorption Spectrophotometer (FAAS). The mean concentrations of Cr, Cu, Pb, and Zn in road-deposited sediments from six plazas were 8.79 ± 1.93, 40.90 ± 24.21, 60.74 ± 22.32, and 164.25 ± 25.0 mg/kg, respectively. Metal enrichment of Cr, Cu, Pb and Zn were approximately xl, x8, x7 and x18 more than the background values respectively. There was no significant temporal variation in metals concentrations of RDS between sampling collections. Generally, RDS from Plaza Libertad has the highest metal concentrations. Cu and Pb metals were highly correlated (R2 = 0.891) indicating possible similar sources. A good correlation (R2 = 0.918) was observed between Pb concentration and the number of vehicles that pass along the plaza per hour. Heavy metal concentrations in sediments from plazas have low hazard quotients but bioaccumulation of metals in the body could cause health effects. Efficiency of digestion procedures varied depending on characteristics, texture and composition of road-deposited sediments. 0.5M HC1 digestion was used because it is simple, cost-effective, time-efficient and it leaches out meaningful amounts of bioavailable metals. Using HC1 as extractant simulates human digestion since human stomach contains HC1 that could leach out metals if road-deposited sediments were ingested.