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 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 Utilization of morphometric and meristic characteristics to identify cultured Tilapias (Oreochromis spp.)Caipang, Christina Joy Rossetti A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1995-03)Meristic characters (DSC, DFRC, AFRO, CFBC and GRC) and morphometric characters (SL, HL, BD, CD and IOW) were utilized to identify five small-sized, with standard lengths ranging from 55- 100 mm., and five big-sized tilapia populations, with standard lengths ranging from 110-195 mm., of forty samples each. Dorsal spine count (DSC) is the least variable while the caudal fin bar count (CFBC) is the most variable meristic character in the tilapia species studied. Analysis of variance (ANOVA) showed that all meristic characters have highly significant differences (p<0.01) among the big-sized tilapias; while in the small-sized tilapias all have highly significant differences (p<0.01) except in caudal fin bar count which was not significantly different (p>0.05). Data on morphometric characters were log-transformed and the four other characters (HL, BD, CD and IOW) were divided by the standard length (SL) to eliminate the effect of size. ANOVA showed that all morphometric characters have highly significant differences (p<0.01) in the big-sized group. Likewise, in the small-sized tilapia species, all morphometric characters have highly significant differences (pU.O5). The study also confirmed that tilapia species studied are morphometrically and meristically distinct.Item Marketing of palay and rice in the Municipality of Bugasong, AntiqueCainap, Ma. Liza A.; Vios, Gregg Louie O. (Division of Social Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2003-03)This study describes the marketing practices and cost, net farm price received by the producers, gross margin received by the middlemen and the problems encountered in palay and rice marketing in the Municipality of Bugasong, Antique. Primary data were gathered from 24 palay producers who were interviewed about their last harvest and ten middlemen who were interviewed about their last week's transactions. Of the total volume sold by the producers (164,700kg), 79.67% went to the wholesaler-retailer-miller. The highest price of Php9.50kg was received by the producers from the National Food Authority (NFA), an institutional buyer. The lowest price of Php6.43/kg was received from the wholesaler-retailer-millers. The marketing costs incurred were Php3.81/kg and Php4.32/kg by the producers who sold within and outside the Municipality, respectively. The depreciation of investments accounted for the largest share of marketing costs of both the producers who sold within and outside of Bugasong. The palay producers who had sold to the NFA received the highest net farm price of Php7.38/kg. The producers who sold palay to the wholesaler- retailer-millers in Bugasong and wholesaler-retailers based outside of Bugasong received the lowest net farm price of Php4.06/kg. By market function, three types of middlemen were identified: wholesaler-retailer-miller, wholesaler-retailer and retailer. The middlemen sold a total volume of 3,603,486.67kg of palay within Bugasong and 972,250.58kg of rice within (45.44%) and outside (54.56%) of Bugasong. The wholesaler-retailers sold the highest volume (63.45%) of palay and the wholesaler-retailer-millers sold the highest volume (23.97%) of rice. The wholesaler-retailer-millers of palay received the highest average selling price of Php8.42/kg while the retailers of rice who sold outside of Bugasong received the highest selling price of Phpl6.50/kg. Among the middlemen who sold outside of Bugasong, the wholesaler-retailer-millers of palay (Phpl.Ol/kg) and wholesaler-retailers of rice (Php7.39/kg) received the highest gross margin. For those who sold within Bugasong, wholesaler-retailer-millers of rice had the highest gross margin received at Php9.10/kg. The retailers received the least gross margin at Phpl.l5/kg. Moreover, the wholesaler-retailer-millers of palay who sold outside of Bugasong and wholesaler-retailers of rice who sold within Bugasong received the highest net return of Php0.33/kg and Php8.22/kg, respectively. The low price of palay and rice was the main problem cited by the producers and the middlemen.Item Sediment organic matter, nitrogen, and phosphorus of four tivers in Miagao, IloiloCahilig, Guen Gian D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)The four rivers of Miagao are examples of aquatic areas where sediment pollution can be related and mostly caused by anthropogenic and non-point sources. The four rivers of Miagao, namely Bacauan, Naulid, Oyungan and Tumagbok rivers, were assessed and observed to have low levels of water due to the dry season, presence of water stagnation due to dikes; other factors such as discharges from domestic activities and livestock wastes, and thick vegetation are also present in the river. The relevance of this study is to provide baseline information about the levels of organic matter, NH4-N, and available phosphorus present in the river, provide public knowledge about the negative impacts of excessive levels of those parameters; and locate possible sources of the pollution through the values obtained. For the total phosphorus concentration present in river sediments, the values are ranging from 0.0648 ppm to 0.154 ppm. Therefore, the values of the available phosphorus are harmful and can cause eutrophication to the river. However, for the values of organic matter and nitrogen, it was reported to be not harmful to the river but can still contribute to the excessive nutrient levels and eutrophication of the river.Item Community structure of superfamily trochoidea (Mollusca Gastropoda) in coral reef sites in Taklong Island National Marine Reserve, GuimarasCagampang, Ma. Thrysky Kharmylle A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Mollusks are considered to be one of the most diverse animal groups. These are widely distributed in tropical areas such as the Philippines. One of the most diverse classes of Phylum Mollusca is Class Gastropoda. It is comprised of more than 65, 000 species. Superfamily Trochoidea is considered to be its largest superfamily with more than 2000 species. Guimaras is a province here in the Philippines. There are a variety of islands that can be found in Guimaras. One of this is Taklong Island located in the municipality of Nueva Valencia. This study describes the community structure of Superfamily Trochoidea in three selected reef flat sampling sites namely, Talisay, Kalirohan, and Banago in Taklong Island National Marine Reserve (TINMR). Plot metlrod was used in this study. There was a total of 369 gastropod individuals collected but only 242 were alive. Live samples belonged to 12 families including 2 families of Super Family Trochoidea, namely, Trochidae and Turbinidae. There were 8 species identified that belonged to these 2 families of Superfamily Trochidea. Under family Trochidae, was 1 species, Tectus fenestratus; under family Turbinidae were three species, namely, Astralium calcar, Astralium provisorium and Turbo argyrostomus. Dead species of Family Trochidae include Trochus conus, Trochus hanleyanus, Trochus sp. and Trochus maculatus. In general, Astralium calcar was found to be the most abundant among all live species. The low diversity of trochoids reported in this study could be an underestimate due to sampling design. Most species of Superfamily Trochoidea, especially the topshells, are nocturnal while this study was conducted at daytime. In general, the gastropod community in TINMR proved to be rich and diverse.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.