• Applied Biological Chemistry
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• v.45 no.4
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• pp.207-211
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• 2002

This study was conducted to increase the shelf life of grape by edible coating material such as methyl cellulose (MC) with antimicrobial substances, n-capric acid isopropyl ester (ci) and sodium nitrate (sn), added by spraying method. The quality changes of packaged grapes with wrapping PE film on EPS tray were investigated for 16 days at $30{\circ}C$. The shelf-lives of C and MCci based on the weight reduction ratio of 7% were 6 days and 9 days, respectively. The reduction rate of acidity of C was higher value than those of treatments during 18 days of storage at $30{\circ}C$. The vitamin C reduction ratios of C, MCsn and MCci were 64.8, 51.5 and 49.8%, respectively, after 16 days at $30{\circ}C$. The reduction rates of firmness of C, MCsn and MCci after 16 days at $30{\circ}C$ were 44.2, 26.5, and 23,2%, respectively compared to that of initial storage grapes. The additions of ci and sn had much affected the reductions of bacteria and yeast counts especially early stage of storage. The hedonic sensory evaluation scores of MCci and MCsn had higher values than those of MC.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.267-271
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• 2005

This experiment was carried out at 450"C, which is relatively lower than the temperature for supercritical water oxidation (600-650$^{\circ}C$). In this experiment, the decomposition rates of various incombustible organic substances were very high. In addition, it was confirmed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium(salt formation).However, to raise the decomposition rate, relatively large amount of sodium nitrate(3-4 times the equivalent weight) was required. When complete oxidation is intended as in the case with PCB, the amount of oxidizer and decomposition cost is important. But when vaporization reduction is required as in the case with nuclear wastes, the amount of radioactive wastes increases instead. But as can be seen in the result of XRD measurement, unreacted sodium nitrate remained unchanged. If oxidation reaction of organic substance simply depends on collision frequency, unreacted sodium nitrate can be recovered and reused, then oxidation equivalent weight would be sufficient. In the gas generated, toxic gas was not found. As the supercritical water medium has high reactivity, it is difficult to generate relatively low energy level SO$_{X}$, and NO$_{X}$.

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.43-50
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• 2008

This study was conducted to investigate the proper supplied conditions of sodium selenate supplied by fertigation to improve functionality of major western vegetables; beet, broccoli, cabbage lettuce, celery, and parsley in highland. In this work, the growth and content of minerals, ascorbic acid, nitrate, and selenium were measured in western vegetables that treated sodium selenate by different concentration, treatment time and treatment frequency. While there was not different in early growth of some western vegetables among different concentration of sodium selenate; 1,2, 5 and $20\;mg{\cdot}L^{-1}$, at 20 days after treatment, the fresh weight was reduced 33% at cabbage lettuce,47% at broccoli, and 74% at parsley compared control in $5\;mg{\cdot}L^{-1}$ treatment. But the fresh weight of beet and celery reduced just 20% and 15% compared control in even $20\;mg{\cdot}L^{-1}$. The ascorbic acid of cabbage lettuce, celery, and beet increased as sodium selenate concentration increased, so that of cabbage lettuce showed 1.2 times compared control in $20\;mg{\cdot}L^{-1}$ treatment and also that of beet and celery increased 10%. But the ascorbic acid of broccoli and parsley was not influenced by treated sodium selenate. As the concentration of sodium selenate increased, the nitrate contents decreased regardless of crops compared control. This reduced effect of nitrate was highest in cabbage lettuce, followed by beet and celery. The mineral contents, such as K, Ca, and Mg, decreased in all crops, as the concentration of sodium selenate increased. The potassium content showed an obvious negative correlationship with the concentrations of sodium selenate regardless of crops, but the magnesium and calcium content did not show significant difference between treatments. The selenium content increased in proportion as increasing sodium selenate concentrations. The broccoli, celery and parsley treated $20\;mg{\cdot}L^{-1}$ sodium selenate showed 24.4 times, 76.4 times, and 560 times higher than control, respectively. When the sodium selenate supplied to some western vegetables in different growth stage, the selenium content increased 1.3 times and 1.4 times higher in early stage than in late stage in cabbage lettuce and broccoli, respectively. However in parsley and celery, the selenium content showed the highest in middle stage. The selenium content increased in proportion as increasing the sodium selenate treatment frequency, but in above 10 times treatment, the increased effect alleviated in parsley, celery, and cabbage lettuce. On the contrary, the selenium content of broccoli increased constantly as treatment frequency increased.

• Textile Coloration and Finishing
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• v.21 no.2
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• pp.14-21
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• 2009

In this article, silk fabric was treated with silver nitrate ($AgNO_3$) as oxidizing agent, with conditions such as concentration, and treating time, and subsequently treated with reducing agents such as sodium boron hydride ($NaBH_4$) and sodium sulfide ($Na_2S$) to obtain cathodic coloration. After coloration of silk fabric, dyeing properties (K/S value), colorfastnesses such as wash, rubbing and light, and antibacterial activity property were examined. $AgNO_3$ treating time and reducing time did not influence K/S value, whereas the pH value at alkaline region showed a high K/S value of silk fabric. The cathodic colorations of silk fabric with both of reducing agents at $30^{\circ}C$ have excellent color fastnesses. Also the high antibacterial activities were obtained by the treatment with silver nitrate even at 1% of lower concentration.

• Journal of Food Hygiene and Safety
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• v.20 no.4
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• pp.217-224
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• 2005

When L. monocytogenes ($10^{5}CFU/mL$) at exponential phase cells were heated for 5 min at $65^{\circ}C$ in the presence of the bacteriocin (30 BU/mL) produced by E. faecium MJ-14, the number of viable cells was markedly reduced at p < 0.05. The bactericidal effect of bacteriocin showed synergism with combination ot organic acids (citric acid or acetic acid) or chemical preservatives (sodium benzoate, sodium lactate, sodium nitrate or potassium nitrate). For example, the number of viable cells was reduced by 4.8 log units under combination of the bacteriocin (30 BU/mL) and sodium nitrate ($100{\mu}g/mL$), while it was reduced by 1.1 log unit only under single treatment of the bacteriocin after 12 k at $37^{\circ}C$. The addition of the bacteriocin (300 BU/mL) into skim milk inoculated with L. monocytogenes ($10^{5}$CFU/mL) reduced the cells by 1.5 log unit, in case of the cell suspension stored at $4^{\circ}C$ for 24 hr. Moreover, L. monocytogenes was reduced by 2 log unit when stored at $-20^{\circ}C$ for 7 days in gound pork added with 300 BU/mL of 린e bacteriocin.

• Journal of Aquaculture
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• v.15 no.1
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• pp.49-60
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• 2002

Research on practices for improving water quality in channel catfish Ictalurus punctatus ponds was conducted at the Auburn University Fisheries Research Station, Auburn, Alabama, in 1998 and 1999. The objective of this two-year study was to determine better management practices to enhance water quality and improve production efficiency. In the first year, oxidation of bottom soil by drying, tilling, and applying sodium nitrate was performed (dry-till and dry-till with sodium nitrate treatments). The second year, based on the results obtained during the first year, precipitation of phosphorus (P) from water by applying gypsum was compared to the dry-till treatment (dry-till and dry-till with gypsum treatments). Control ponds were not subjected to bottom drying, tilling, sodium nitrate, or gypsum treatment. Channel catfish fingerings were stocked at 15,000/ha. In the first year, water in ponds from dry-till and dry-till with sodium nitrate treatments had lower concentrations (P < 0.01) of soluble reactive P, nitrate ($NO_{3} ^{-}) and nitrite ($NO_{2} ^{-}) nitrogen (N), total ammonia ($NH_3$) nitrogen, total suspended solids and turbidity, and higher values of pH, Secchi disk visibility, total alkalinity, total hardness, and calcium ($Ca^{2+}) hardness than water in control ponds. Ponds of the dry-till treatment also had lower concentrations (P < 0.01) of total P and total N than control ponds. Total fish production and survival rate did not differ among the treatments (P > 0.05). The findings suggested that drying and tiling pond bosoms between crops could achieve water quality improvement. Applying sodium nitrate to dry, tilled pond bosoms did not provide water quality improvement. In the second year, the treatment with the best results from the first year, dry-till, was compared with a dry-till with gypsum treatment. Enough gypsum was applied to give a total hardness of about 200 mg/L, and gypsum was reapplied as needed to maintain the hardness. Compared to the control, dry-till and dry-till with gypsum treatments had lower concentrations (P < 0.01) of total and soluble reactive P, total N, and total $NH_3$-N, and higher concentrations (P < 0.01) of dissolved oxygen. Ponds of the duty-till with gypsum treatment also had lower concentrations (P < 0.01) of chlorophyll $\alpha$, chemical oxygen demand, and total alkalinity than the control. Total fish production and survival rate did not differ (P > 0.05) among the treatments. These findings suggest that drying and tilling pond bosoms between crops and treating low hardness waters with gypsum could achieve water Quality improvement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.606-613
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• 1997

The changes of contents in trimethylamine oxide nitrogen(TMAO-N), trimethylamine nitrogen(TMA-N), dimethylamine nitrogen(DMA-N), nitrite nitrogen(nitrite-N), nitrate nitrogen(nitrate-N) and the effect on the formation of N-nitrosamine(NA) during fermentation were investigated with salted anchovy added different amounts of sodium nitrite, sodium nitrate and ascorbic acid, respectively. When the sodium nitrite was added in salted anchovy, the contents of nitrite-N was decreased during fermentation . Whereas the formation of N-nitrosodimethylamine(NDMA ) was increased . Contents of TMAO-N was decreased, while TMA-N and DMA-N were increased during fermentation in all samples. Addition of ascorbic acid inhibited the formation of NDMA significantly. The formation of NDMA was inhibited by 81.3% at the concentration of 130mM as compared with non-added the control group. The aqueous model system was used for the evaluation of ascorbic acid(inhibitor) or thiocyanate (promoter) on the formation of NDMA using salt-fermented anchovy added with sodium nitrite. The optimum pH on the formation of NDMA was shown to be 3.8, and ascorbic acid inhibited the formation of NDMA whereas thiocyanate promoted. NDMA was not detected in the salt-fermented anchovy (control sample). However it is a possibility to form carcinogenic NDMA in stomach if both saltfer-mented anchovy and the materials contained abundant nitrite or nitrate were took in.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1173-1177
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• 2000

This study investigated the nitrate reduction ability of Micrococcaceae on pigment formation in Chinese- style sausage. One hundred ppm sodium nitrite and 150 ppm sodium nitrate was added asepticly to ground pork which was then inoculated with $10^7CFU/g$ of either Micrococcus varians, Staphylococcus carnosus or Staphylococcus xylosus. All samples were cured at $20{^{\circ}C}$ or $30{^{\circ}C}$ for 3 days and then color, residue nitrite, nitrosyl pigment and residue nitrate were determined. The results indicated that samples inoculated with S. xylosus had higher a- and b- values due to nitrate reduction and pigment production after 3 days curing and these values were higher at the higher curing temperature. The nitrosyl pigment of the samples with S. xylosus had highest values after 3 days curing at both $20{^{\circ}C}$ and $30{^{\circ}C}$. However, sample inoculated with S. carnosus and S. xylosus had lower nitrate contents than the sample inoculated with M. varians. At $30{^{\circ}C}$ as well as S. carnosus and M. varians had a stronger decreasing in nitrate concentration during curing at $20{^{\circ}C}$. Moreover, samples inoculated with S. xylosus and S. carnosus had a higher residual nitrite content during curing at $20{^{\circ}C}$ or $30{^{\circ}C}$. In conclusion, two Staphylococci strains tested were most optimum starter cultures for improving pigment formation during Chinese-style sausage curing.

• Journal of Environmental Science International
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• v.14 no.10
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• pp.919-928
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• 2005

This study introduces the development of new supercritical water oxidation(SCW)(multiple step oxidation) to destruct recalcitrant organic substances totally and safely by using sodium nitrate as an oxidant. This method has solved the problems of conventional SCW, such as precipitation of salt due to lowered permittivity, pressure increase following rapid rise of reaction temperature, and corrosion of reactor due to the generation of strong acid. Destruction condition and rate in the supercritical water were examined using Polyvinyl Chloride(PVC) and ion exchange resins as organic substances. The experiment was carried out at $450^{\circ}C$ for 30min, which is relatively lower than the temperature for supercritical water oxidation $(600-650^{\circ}C)$. The decomposition rates of various incombustible organic substances were very high [PVC$(87.5\%)$, Anion exchange resin$(98.6\%)$, Cationexchange resin$(98.0\%)$]. It was observed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium (salt formation). However, relatively large amount of sodium nitrate (4 equivalent) was required to raise the decomposition ratio. For complete oxidation of PCB was intended, the amount of oxidizer was an important parameter.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.503-513
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• 2003

A single particle analytical technique, called low-Z electron probe X-ray microanalysis (low-Z EPMA) was applied to characterize atmospheric particles collected in Busan, Korea, over a daytime period in Dec. 2001. The ability to quantitatively analyze the low-Z elements, such as C, N, and 0, in microscopic volume enables the low-Z EPMA to specify the chemical composition of individual atmospheric particle. Various types of atmospheric particles such as organics, carbon-rich, aluminosilicates, silicon oxide, calcium carbonate, iron oxide, sodium chloride, sodium nitrate, ammonium sulfate, and titanium oxide were identified. In the sample collected in Busan, sodium nitrate particles produced as a result of the reaction between sea salt and nitrogen oxides in the atmosphere were most abundantly encountered both in the coarse and fine fractions. On the contrary, original sea salt particles were rarely observed. The fact that most of the carbonaceous particles were distributed in the fine fraction implies that their origin is anthropogenic.