• Journal of Soil and Groundwater Environment
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• v.14 no.4
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• pp.23-32
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• 2009

The sorption of europium (Eu (III)) onto kaolinite and the influence of humic acids over a range of pH 3 ~ 11 has been studied by batch adsorption experiment (V/m = 250 : 1 mL/g, $C_{Eu(III)}\;=\;1\;{\times}\;10^{-5}\;mol/L$, $C_{HA}\;=\;5{\sim}50\;mg/L$, $P_{CO2}=10^{-3.5}\;atm$). The concentrations of HA and Eu(III) in aqueous phase were measured by UV absorbance at 254nm (e.g., $UV_{254}$) and ICP-MS after microwave digestion for HA removals, respectively. Results showed that the HA sorption onto kaolinite was decreased with increasing pH and their sorption isotherms fit well with the Langmuir adsorption model (except pH 3). Maximum amount ($q_{max}$) for the HA sorption at pH 4 to 11 was ranged from 4.73 to 0.47 mg/g. Europium adsorption onto the kaolinite in the absence of HA was typical, showing an increases with pH and a distinct adsorption edge at pH 3 to 5. However in the presence of HA, Eu adsorption to kaolinite was significantly affected. HA was shown to enhance Eu adsorption in the acidic pH range (pH 3 ~ 4) due to the formation of additional binding sites for Eu coming from HA adsorbed onto kaolinite surface, but reduce Eu adsorption in the intermediate and high pH above 6 due to the formation of aqueous Eu-HA complexes. The results on the ternary interaction of kaolinte-Eu-HA are compared with those on the binary system of kaolinite-HA and kaolinite-Eu and adsorption mechanism with pH was discussed.

• Journal of agriculture & life science
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• v.50 no.4
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• pp.147-155
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• 2016

This study presented a measure for turning by-products, released from land farming sites, into resources. The measure involved adding food by-products such as rice bran and nonfat soybean to the sludge, released from the eel farming sites, inoculating the lactic acid bacteria, Aspergillus oryzae, and Bacillus subtilis by step, fermenting them, and measuring the changed ingredients of the fermented fodder. The water content of the fermented fodder by the step of preparation was the first-step fermented product (14.6%) using the lactic acid bacteria, and the second and third-stage fermented product (33.0% and 34.0% respectively) using Aspergillus oryzae and Bacillus subtilis. The pH level was found to be 5.38 in the first-step fermented product due to the secretion of lactic acid caused by the lactic acid bacteria, and the pH level of the second and third-stage fermented products was 5.66 and 7.26, respectively, showing that the pH level increased. The phytic acid content was 0.126g/100g in the first-step fermented product, 0.004g/100g in the second-stage fermented product, and 0.093g/100g in the third-stage fermented product. The measurement of nitrogen content revealed that the amino nitrogen content was high with 1226.37mg% in the second-stage fermented product, and a little lower with 710.18mg% in the third-stage fermented product. The ammonium nitrogen content increased from 0.988mg/kg in the first-stage fermented product to 1.502mg/kg in the third-stage fermented product. Total nitrogen content increased to 2.78% in the first-stage fermented product, 4.08% in the second-stage fermented product, and 4.85% in the third-stage fermented product. As fermentation continued with the three microbes, the phytic acid decreased, and the protein decomposition rate increased. Also, due to the 3 step fermentation, the low-molecule nitrogen ingredient content increased, suggesting that the fodder was developed to offer high digestion and absorption.

• Korean Journal of Poultry Science
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• v.32 no.4
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• pp.291-300
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• 2005

Two experiments were carried out to assess the appropriate incubation conditions namely; duration, moisture content and the ideal microbial inoculant for fermented dried food waste(EW) offered to broilers. The nutrient utilization of birds fed the FW diets at varying dietary inclusion rates was also compared with a control diet. In Experiment 1, different moisture contents(MC) of 30, 40, 50 and $60\%$ respectively were predetermined to establish the ideal duration of incubation and the microbial inoculant. A 1mL Aspergillus oryzae(AO) $(1.33\times10^5\;CFU/mL)$ was used as the seed inoculant in FW. This results indicated that the ideal MC for incubation was $40\~50\%$ while the normal incubation time was > 72 hours. Consequently, AO seeds at 0.25, 0.50, 0.75 and 1.00mL were inoculated in FW to determine its effect on AO count. The comparative AO count of FW incubated for 12 and 96 hours, respectively showed no significant differences among varying inoculant dosage rates. The FW inoculated with lower AO seeds at 0.10, 0.05 and 0.01mL were likewise incubated for 72 and 96 hours, respectively and no changes in AO count was detected(p<0.05). The above findings indicated that the incubation requirements for FW should be $%40\~50\%$ for 72 hours with an AO seed incoulant dosage rate of 0.10mL. Consequently, in Experiment II, after determining the appropriate processing condition for the FW, 20 five-week old male Hubbard strain were used in a digestibility experiment. The birds were divided into 4 groups with 5 pens(1 bird per pen). The dietary treatments were; Treatment 1 : Control(Basal diet), Treatment 2 : $60\%$ Basal+4$40\%$ FW, Treatment 3 : $60\%$ $Basal+20\%\;FW+20\%$ AFW(Aspergillus oryzae inoculate dried food-waste diet) and Treatment 4: $60\%$ Basal+$40\%$ Am. Digestibility of treatment 2 was lowed on common nutrients and amino acids compared with control(p<0.05) and on crude fat and phosphorus compared with AFW treatments(T3, T4)(plt;0.05). Digestibility of treatment 3 and 4 increased on crude fiber and crude ash compared treatment 2 (p<0.05). Digestibility of control was high on agrinine, leucine, and phenylalnine of essential amino acids compared with treatment 3 and 4(p<0.05), and diestibility of treatment 3 and 4 was improved on arginine, lysine, and threonine of essential amino acids. Finally, despite comparable nutrient utilization among treatments, birds fed the dietary treatment containing AO tended to superior nutrient digestion to those fed the $60\%$ Basa1+$40\%$ FW.