• Journal of Environmental Science International
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• v.11 no.3
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• pp.241-246
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• 2002

One of the Musty and earthy smell compounds in raw water is generally attributed to 2-methylisoborneol (2-MIB). It is well known that activated carbon and oxidants such as $O_3$, Cl $O_2$, are effective ways to control 2-MIB. In isotherm equilibrium experiments, 2-MIB in distilled water was much more adsorbed to the activated carbon(A/C) than raw water containing dissolved organic carbon (DOC). The Freundlich constants(k) of distilled water and raw water were 3.36 and 0.049, and 1/n values were 0.80 and 0.42, respectively. The 2-MIB residual rate were Y = $e^{-0}$.55x/~ $e^{-0}$.54x/ with Ozone( $O_3$) dose by 5 minutes contact time at the 241 and 353 ng/L initial concentrations. The 2-MIB residual rate were Y = $e^{-0}$.32x/~ $e^{-0}$.35x/ with Chlorine dioxide(Cl $O_2$) dose by 15 minutes contact time at the 89 and 249 ng/L initial concentrations. 2-MIB was decreased from 1911 ng/L to 569ng/L by post-ozonation(70%removal efficiency) and removal efficiencies of 2-MIB by the following 4 kinds Granular Activated Carbon(GAC) process such as coal base, coconut base, wood base and zeolite＋carbon base were 95.8, 89.5, 88.4, and 93.7% respectively.ely.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.86-86
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• 2001

The aims of this work were to determine the acrosin activity and to evaluate the structural and functional integrity of AS boar spermatozoa. The acrosin activity of spermatozoa were 5.40, 4.10 and 3.40 mIU/10$^{6}$ sperm in raw, extended and frozen semen respectively , which differed significantly each other (P<0.05). After the raw and extended semen were exposured to cold and thermal shock, the acrosin activities of spermatozoa in the raw semen were 5.39, 5.21 and 5.29 mIU/10$^{6}$ sperm for control (non-shock), cold shock and thermal shock, and those of extended semen were 4.21, 3.98 and 4.00 mIU/10$^{6}$ sperm. This value among treatments did not differ significantly. The acrosin activities of spermatozoa in the extended and stored semen were 3.27, 3.52, 3.46 and 3.23 mIU/10/suup 6/ sperm, while hypo-osmotic test(HOST) values were 56.5%, 64.7%, 66.0% and 56.0%, following 4 days storage at 4$^{\circ}C$, 17$^{\circ}C$ , $25^{\circ}C$ and 37$^{\circ}C$, respectively. The results at 17$^{\circ}C$ and $25^{\circ}C$ appeared to be best compared with the other storage temperatures.

• Journal of the Korean Society of Food Culture
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• v.37 no.6
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• pp.540-546
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• 2022

This study aimed to determine the changes in the vitamin B₅ content of raw and cooked vegetables. The nineteen vegetables were subjected to different cooking methods, viz. blanching, boiling, pan-broiling, and steaming. Vitamin B₅ was quantified by reversed-phase high-performance liquid chromatography (HPLC) using photodiode-array (PDA) detection (200 nm). The standard reference materials (SRM) were used to validate the accuracy of vitamin B₅ measurement method used in this study. The cooking yields ranged from 82.63 to 107.62% and decreased in most of the vegetables except bitter melon, curled mallow, and eggplant. The raw kabocha squash, Danhobak, had the highest vitamin B₅ content (0.671 mg/100 g) among the samples. All cooked vegetables showed lower vitamin B₅ content compared to the raw samples. The true retention ranged from 0% (crown daisy, blanching) to 84.49% (kabocha squash, steaming). These results indicate that vitamin B₅ is degraded after cooking. Pan-broiling and steaming are better cooking methods than the others for retaining vitamin B₅. The true retention of vitamin B₅ in the samples markedly depends on the cooking method and food matrix. These results can be used as important basic data for nutritional evaluation of meals.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.699-703
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• 2005

An experiment was conducted to investigate the effects of various dietary levels of Saccharomyces cerevisiae (SC) on the growth performance and meat quality (i.e., tenderness and oxidative stability) of Ross broiler chickens. Two hundred and forty dayold broiler chicks were fed four experimental diets with graded levels of SC at 0.0, 0.3, 1.0 and 3.0%. Each treatment consisted of six cages with 10 chicks per cage. Feed and water were provided ad libitum throughout the experiment that lasted for 5 wk. Birds were switched from starter to finisher diets at 3 wk of age. The average BW gains of broiler chickens increased (linear p<0.05) during either 0-3 or 0-5 wk of age as dietary SC levels increased. A linear effect (p<0.05) of SC on feed intake during either 4-5 wk or 0-5 wk of ages was also monitored. The addition of SC to the control diet significantly lowered shear forces in raw breast, raw thigh, and boiled drumstick meats (linear p<0.05). Upon incubation, 2-thio-barbituric acid-reactive substances (TBARS) values increased gradually in breast and thigh meats while more dramatic increase was noted in skin samples. The TBARS values of either breast or thigh meats were not significantly affected (p>0.05) by dietary treatments up to 10 d of incubation. At 15 d of incubation, TBARS values of breast and thigh meats from all SC-treated groups were significantly lower (p<0.05) than those of the control. It appears that dietary SC could enhance growth performance of broiler chickens, and improve tenderness and oxidative stability of broiler meats.

• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.284-294
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• 1988

To measure the mutagenic activity of micro-organic pollutants in drinking water, mutagenicity test was conducted using Salmnella typhimurium TA 98 strain on the water sample taken from three water supply stations and six tap water in Seoul in July and November 1987. The results were as follows : 1. The average amounts of organic matters in raw, treated, and tap water sampled in July were 0.38mg/l, 0.28mg/l, and 0.45mg/l. respectively, and sampled in November were 0.34mg/l, 0.24mg/l, and 0.22mg/l, respectively. The amount of organic matters of tap water sampled in November did not increase while that of tap water sampled in July increased compare to those of raw or treated water. 2. The amount of organic matters is the highest in neutral fraction compare to acidic and basic fractions. 3. In the five out of six tap water and raw water of Paldang and Kuui station sampled in July, the mutagenicity ratios were greater then two (both direct and indirect mutagenicity). 4. In the three out of six tap water and raw and treated water of Kuui station sampled in November, the mutagenicity ratios were greater than two. 5. While mutagenic activities were low in acidic and basic fraction, they were high in neutral fraction. The samples which had high mutagenic acitivity in the total amount also showed high mutagenic activity in neutral fraction. 6. While mutagenic acitivity was decreased after the treatement of water, it was increased in tap water as the distance from the water supply station increases.

• Food Science of Animal Resources
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• v.21 no.2
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• pp.149-155
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• 2001

The aims of this study were to examine contamination sources and provide the basic data in establishment of sanitary standard for raw pork meat. From \"Random sampling(I)\", initial total plate counts of post-slaughter samples for the group A, B and C were 1.5${\times}10^4$cfu/$textrm{cm}^2$, 5.5${\times}10^5$cfu/$textrm{cm}^2$ and 1.8${\times}10^4$cfu/$textrm{cm}^2$, respectively, and of post-prechilling samples for the group A, B and C were 1.0${\times}10^4$cfu/$textrm{cm}^2$, 4.6${\times}10^5$cfu/$textrm{cm}^2$ and 2.5${\times}10^4$cfu/$textrm{cm}^2$, respectively. Initial total plate counts of post-transportation samples for the group D, E and F did not increased, as did the group A, B and C. From \"Normal sampling(II)\", initial total plate counts of post-slaughter, post-prechilling, post-transportation and post-2 days preservation samples were 7.3${\times}10^4$cfu/$textrm{cm}^2$, 9.6${\times}10^4$cfu/$textrm{cm}^2$, 2.0${\times}10^5$cfu/$textrm{cm}^2$ and 2.5${\times}10^5$cfu/$textrm{cm}^2$, respectively. From \"Clean sampling(III)\", initial total plate counts of post-slaughter, post-prechilling, post-transportation and post-2 days preservation samples were decreased to 7.0${\times}10^2$cfu/$textrm{cm}^2$, 7.5${\times}10^2$cfu/$textrm{cm}^2$, 8.5${\times}10^2$cfu/$textrm{cm}^2$ and 5.5${\times}10^3$cfu/$textrm{cm}^2$, respectively, compared with "Normal sampling(II)". No E. coli O157:H7, Staphylococcus aureus and Salmonella were detected at each sampling step. Consequently, a slaughter method like "Clean sampling(III)" showed a better sanitary effect to low total plate counts of 10$^2$∼10$^3$times, compared with "Normal sampling(II)". The one of contamination sources for raw pork meat was at a slaughtering step, and "Clean sampling" method may be considered as the one of sanitary standards.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.367-371
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• 2004

This report describes the determination of ceftiofur residues in milk from treatment of lactating dairy cattle by intramuscular injection of three consecutive daily doses of about 1 mg /kg BW, the recommended label dosing. The separation of ceftiofur was achieved on $C_1_8$ reverse phase column. The mobile phase consisted of 0.1% trifluoracetic acid in water (A) and 0.05% acetic acid in acetonitrile (B) and grediently flowed at the flow rate of 0.4 mL/min. As a result of analysis of blank raw bovine milk samples, matrix interference was not shown. Limit of detection and limit of quantitaion was 0.5 ng/mL and 1 ng/mL, respectively. The values of precision and recovery satisfied the guideline of National Veterinary Research and Quarantine Service (NVRQS, Korea). The mean residual concentration of ceftiofur in milk did not exceed 3.71 ng/mL when ceftiofur was administered intramuscularly to lactating dairy cattle for 3 consecutive days at 1 mg/kg of BW per day. It is much lower than the proposed MRL (100 ng/mL) of ceftiofur in milk.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.482-486
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• 2009

The aim of this study was to optimize a simple, fast, and economical analysis procedure for the determination of 16 different pesticides in raw milk via GC/MSD. Analyses were performed via gas chromatography with electron impact mass spectrometric detection in the selected ion monitoring mode (GC/MSD-SIM) using Pentachloronitrobenzene as the internal standard. The modified sample preparation methodology was based on the Pesticide Analytical Manual (PAM) of the FDA concerning fat extraction, ACN-ether partitioning, and clean-up of the Sep-Pak florisil cartridge. The modified methodology for the determination of the 16 pesticides was validated. The range of LOQs of the 16 pesticides was likely three times lower than their Maximum Residence Levels (MRLs). The recoveries of most of the pesticides were acceptable at the fortification levels of 0.5 and 1.0 ${\mu}g/mL$ and their RSD (%) level was less than 20%. None of the 16 pesticides were detected in the selected raw milk samples.

• Journal of environmental and Sanitary engineering
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• v.5 no.1
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• pp.65-72
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• 1990

To study on the water quality of domestic purifier, twenty four samples of clean water by purifier and the raw water(tap water) were tested for biological and physico-chemical examination and were checked for style of purification and the period elapsed after changing of purification medium. The results were as follows; Biological and physico-chemical findings of raw water were not exceeded standard values. Average number of general bacteria,2.coli and pH in clean water were significantly higher than that of raw water(respectively, p<0.01), but mean contents of turbidity, chloride, nitrate and iron in clean water were significantly lower than that of raw water(respectively, p<0.01). In general count of bacteria and E.coli, a half of the clean water of ceramic filter and roverse osmosis style were exceeded standard values for drinking water. All of the pH of the ion exchange style clean water were exceeded standard values. But other findings were within standard values. In average bacterial counts and physico-chemical findings of clean water by purification style of purifier, clean water of ion exchange style purifier were lowest number of general bacteria and not detected in 2. coli. But other items were highest. The longer period elapsed after changing of purification medium were the higher contents of biological and physico-chemical findings of clean water.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.1
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• pp.39-46
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• 2009

A method to improve water treatment efficiency by coagulant overdosing for high pH raw water at a drinking water treatment plant (WTP) which had no pH adjusting facilities was investigated. Poly aluminum chloride (PACl) was used for coagulant, and turbidity removal efficiency was evaluated as a function of PACl dosage increases. pH and turbidity of supernatant of jar-tester were 7.10 and 0.50 NTU respectively, when the turbidity, pH, alkalinity, water temperature, conductivity of raw water were 1.75 NTU, 9.38, 46.5 mg/L, $6.4^{\circ}C$, $400{\mu}s/cm$, respectively. Turbidity of settled water was reduced from 2.18 NTU to 0.28 NTU (87% reduction) when PACl dosage was increased from 16 mg/L to 45 mg/L at a full scale WTP. This can be attributed to the recovery of coagulant efficiency by pH reduction with the increase of coagulant dose, however coagulation efficiency was reduced with the formation of Al(OH)4- by PACl addition at higher pH. Coagulant overdosing was proven to be a rapid and effective method for high pH raw water, which can be applied at drinking WTP.