• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.24-31
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• 2008

Sulfate reducing bacteria (SRB) is universally distributed in the sediment, especially in marine environment. SRB reduce sulfate as electron acceptor to hydrogen sulfide in anaerobic condition. Hydrogen sulfide is reducing agent enhancing the reduction of the organic and inorganic compounds. With SRB, therefore, the degradability of organic contaminants is expected to be enhanced. Ferrous iron reduced from the ferric iron which is mainly present in sediment also renders chlorinated organic compounds to be reduced state. The objectives of this study are: 1) to investigate the reduction of TCE by hydrogen sulfide generated by tht growth of SRB, 2) to estimate the reduction of TCE by ferrous iron generated due to oxidation of hydrogen sulfide, and 3) to illuminate the interaction between SRB and ferrous iron. Mixed bacteria was cultivated from the sludge of the sewage treatment plant. Increasing hydrogen sulfide and decreasing sulfate confirmed the existence of SRB in mixed culture. Although hydrogen sulfide lonely could reduce TCE, the concentration of hydrogen sulfide produced by SRB was not sufficient to reduce TCE directly. With hematite as ferric iron, hydrogen sulfide produced by SRB was consumed to reduce ferric ion to ferrous ion and ferrous iron produced by hydrogen sulfide oxidation decreased the concentration of TCE. Tests with seawater confirmed that the activity of SRB was dependent on the carbon source concentration.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.5
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• pp.911-921
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• 1997

Recently the interest in natural dyeing has been increased because of the color clarity, natural grace and reactionism in fashion. Indigo dyeing, safflower dyeing and Gal-ott in Cheju-Do become generally known, so the study about the natural dyeing is continued with national intrust and support. In this study, 1 used artemisia for various dyeing tests because we can get it easily. 1 tested the dyeability in wool as well as cotton and silk with wormwood in natural dyeing material. I also dyed nylon with the same material for the comparison of the molecular structure. The mercerization and the chitosan treatment were done in cotton to improve the low dyeability in the natural dyeing. The result of this study are as follows; We have to dye repeatedly to get deep color in natural dyeing, and mordant treatment brought good result in color difference and dyeing fastness. 1. Compared with silk, wool and nylon, the dyeability of cotton was the worse. The color difference of cotton was 18.81 without mordants , and 24.05 with mordant. The dyeability of cotton was much increased by mordants such as potassiumdichromate, copper sulfate, iron sulfate and salt water. The color of cotton was turned into yellow-green in potassium dichromate and yellow-green with deep green in copper sulfate. The mercerization and the chitosan treatment of cotton made the improvement in color, dyeability, laundering fastness, abrasion fastness. 2. The color difference of silk was 3 times as high as cotton. It showed the similar degree with the chitosan treated-cotton. That is to say, silk had good dyeability because it contains amino group and carboxyl group. The dyebility of silk was increased by a mordant such as iron sulfate, potassium dichromate and salt water, Drycleaning fastness showed 5 grade, abrasion-fastness was high over 4~5 grade and sunlight fastness showed 1 grade in all case. 3. The color difference of wool was the best among four fabrics because of 18 kinds of amino acids. It is considered that the sulfate of wool has the polarity and help metal- mordants get the better dyeability such as potassium dichromate, iron sulfate, copper sulfate, and aluminum chloride. The color was reddish-green in potassium dichromate, yellow.greenin iron sulfate and copper sulfate, and yellow in the rest mordants. Drycleaning fastness of wool showed over 4~5 grade, abrasion fastness 5 grade. Sunlight-fastness 1 grade. 4. The dyeability of nylon was almost same because of the similar molecular structure with silk. The clarity of color was poor. The color was yellow-green in copper sulfate and yellow in the rest mordants. Laundering fastness and abrasion-fastness of nylon was good. Sunlight- fastness represented 1 grade.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.103-106
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• 2008

A broiler experiment was conducted to compare the effects of supplementary iron sources and levels on the iron content of broiler meat. Two hundred and fifty hatched Ross broiler chickens were randomly assigned to 5 dietary treatments. Each treatment had 5 replicates of 10 birds (5 males and 5 females). Birds were housed in raised floor batteries and fed traditional broiler diets ad libitum for 5 weeks. Dietary treatments were as follows: Control, Fe-Met 100 (100 ppm iron as Fe-methionine), Fe-Met 200, $FeSO_4$ 100 (100 ppm iron as $FeSO_4{\cdot}7H_2O$) and $FeSO_4\;200$. There were no significant differences among treatments in parameters related to production performance. Liver contained approximately 10 times more iron than the leg muscle which contained approximately 3 times more iron than either breast muscle or wing muscle. Significant differences in iron content in the broiler meat were observed. In the breast meat, Fe-Met treatments were significantly (p<0.05) higher than other treatments in iron content. In the leg meat, Fe-Met treatments and $FeSO_4\;200$ treatment were significantly higher than the control in iron content. In the wing muscle, Fe-Met 200 treatment was significantly higher than other treatments in iron content. Iron content in the liver was significantly influenced by source and supplementation level of iron. Fe-Met treatments were higher than $FeSO_4$ treatments and 200 ppm treatments were higher than 100 ppm treatments in iron content in the liver. It is concluded that iron-methionine chelate is more efficient than iron sulfate and 200 ppm iron supplementation as Fe-Met is recommended for maximum iron enrichment in broiler meat.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.406-411
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• 2003

The objective of this study was to investigate the effects of iron supplementation and nutrition education on the iron status and anemia of middle school girls in Ulsan city in Korea. The subjects were already diagnosed as having anemia (hemoglobin < 12 g/dL) or iron deficiency (ferritin < 12 ng/mL and/or transferrin sataturation < 14 %). Over a period of three months, one iron tablet (80 mg Fe as ferrous sulfate/day) was administered to the iron deficient subjects and two tablets (160 mg Fe as ferrous sulfate/day) were administered to the anemia subjects. Total calorie intake of subjects was 82.1 % of RDA. The iron intake of subjects was 91.3 % of RDA and the Ca intake was 78.8 % of RDA. The basal hemoglobin concentration of subjects averaged 12.8 1.2 g/dL, and this increased significantly (p < 0.001) to 13.2 0.9 g/dL after iron supplementation. The basal ferritin concentrations were 14.9 14.2 ng/mL and these significantly increased to 26.6 19.8 ng/mL (p < 0.001). The level of total iron binding protein (TIBC) significantly decreased from the initial 523.1 108.7 $\mu\textrm{g}$/dL to 462.2 90.2 $\mu\textrm{g}$/dL (p < 0.001) after iron supplementation. Anemia symptoms such as‘Being bruised easily’, ‘Inflamed inner mouth’, and ‘Pale face’ improved significantly after iron supplementation in the subjects. There was a negative correlation between their class & year ranking and serum iron level, transferrin saturation after nutritional education and iron supplementation. It was shown, therefore, that the higher the improvement of their anemia level after iron supplementation, the higher their academic performance. It was shown that there was some improvement of their dietary attitudes after nutritional education, and that their serum level related to anemia symptoms and iron nutrition was improved after iron supplementation.

• Textile Coloration and Finishing
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• v.11 no.4
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• pp.39-49
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• 1999

In order to study the properties of cochineal colors, uv-visible spectra of cochineal colors solution, dyeing properties on the wool in several dyeing conditions and thermodynamic parameters were investigated. UV-visible spectra of cochineal colors solution showed hypochromic effect with the lapse of irradiation time but bathochromic shift with decreasing acidity of solution and addition of metallic ions. The concentration of cochineal colors in wool fiber increased with the increase of dyeing temperature, time, and acidity of initial dyebath. The value of apparent diffusion coefficients and standard affinities of dyeing decreased with the increase of dyeing temperature. The standard heats of dyeing$(\Delta{H}^\circ)$ and variation of entropy$(\Delta{S}^\circ)$ increased with the increase of concentration of initial dyebath. The activation energy$(E_a)$ were calculated to be 1.399~2.595kcal/mol in condition of 6~1%(o.w.f) dyebath. Wool fabrics were dyed reddish blue by iron sulfate, copper sulfate, aluminum acetate and tannic acid, and red by tin chloride, respectively. Lightfastness of wool fabrics dyed by cochineal colors were increased by mordant treatment, especially copper sulfate and iron sulfate treatment.

• Journal of Korean Society on Water Environment
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• v.18 no.4
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• pp.379-386
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• 2002

In this study, estimation model for iron compound originated from upflow, anaerobic fixed bed reactor, which treats sewage domestic wastewater, was developed. The estimation model was formulated by a mathematical expression which was based on the mass balance. Below the HRT of 60 minute, sulfide concentration combining with iron $FeS_2$ is the highest because the maximum sulfate consumption rate $V_{maxS}$ and half-saturation constant of sulfate $K_{mS}$ exert an important effect on the estimation model as temperature was increased. But increment of $FeS_2$ concentration is weakened above the HRT of 60 minutes and represent the lowest value at the HRT of 108 minutes. It implies that liquid phase distribution ratio of sulfide ${\alpha}r$ becomes lower as temperature was increased. While phosphorus concentration combining with iron $Fe_3(PO_4)_3$ is increased as HRT and temperature are increased, which is affected by phosphorus removal rate constant $k_p$. As the result of estimating the iron concentrations of corrosion by the model, the concentration of iron corrosion is higher than any other at the HRT of 108 minute and $20^{\circ}C$. The predicted values were compared with measured ones at different HRT(13.5, 27, 54, 108 min) and temperature(20, 25, $30^{\circ}C$). The experimental data could be fitted with the simulated curves. Therefore, the mathematical expression could be applicable to design full-scale wastewater treatment plants.

• Journal of the Mineralogical Society of Korea
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• v.24 no.3
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• pp.217-224
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• 2011

Removal of dissolved selenium by D. michiganensis, a iron-reducing bacterium, and effects of dissolved metal elements such as iron, sulfate, and copper were investigated. Selenide that was reduced from selenite (2 mM) by D. michiganensis was gradually removed from the aqueous medium. As the reduced selenide was combined with aqueous iron, it was precipitated as a nanoparticulate iron-selenide. Sulfate and copper negatively affected the microbial selenite reduction, and the copper was especially toxic to the bacterium, inhibiting a microbial removal of dissolved selenite. These results show that it should be carefully biotreated for a selenium-contaminated site considering in situ sulfate or copper distribution and concentration. Consequently, the formation of iron-selenide by bacteria will be an important measure for preventing a long-distance migration of selenium in the subsurface environments.

• Journal of the Korean Chemical Society
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• v.19 no.2
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• pp.142-146
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• 1975

The formation of iron oxide hydroxide in a ferrous sulfate was studied in different contents of iron in the solution at a temperature range of 90 to $100^{\circ}C$ under 1${\sim}$3 atmospheres. The Mohr's salt thus formed was hydrolyzed under 1 to 3 atmospheres, in 14 to 72 g/l of iron content in the solution pH 3 or 6 for two hours at 90 to $100^{\circ}C$. The results obtained was as follows; 1) In Mohr's salt solution, as the iron content was increased, with decreasing the concentration of hydrogen ion, the yield of iron oxide hydroxide was gradually increased. 2) When iron content in Mohr's salt solution was 42.81 g/l, 91.5% of iron was recovered in the form of $\alpha$-goethite similar to yellow grade of natural goethite. 3) When $\alpha$-goethite obtained was calcined of $500^{\circ}C$, it was turned into ${\alpha}$-ferric oxide with a redish brown colour.

• Korean Journal of Materials Research
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• v.20 no.6
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• pp.301-306
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• 2010

The chemical formula of magnetite ($Fe_3O_4$) is $FeO{\cdot}Fe_2O_3$, t magnetite being composed of divalent ferrous ion and trivalent ferric ion. In this study, the influence of the coexistence of ferrous and ferric ion on the formation of iron oxide was investigated. The effect of the co-precipitation parameters (equivalent ratio and reaction temperature) on the formation of iron oxide was investigated using ferric sulfate, ferrous sulfate and ammonia. The equivalent ratio was varied from 0.1 to 3.0 and the reaction temperature was varied from 25 to 75. The concentration of the three starting solutions was 0.01mole. Jarosite was formed when equivalent ratios were 0.1-0.25 and jarosite, goethite, magnetite were formed when equivalent ratios were 0.25-0.6. Single-phase magnetite was formed when the equivalent ratio was above 0.65. The crystallite size and median particle size of the magnetite decreased when the equivalent ratio was increased from 0.65 to 3.0. However, the crystallite size and median particle size of the magnetite increased when the reaction temperature was increased from $25^{\circ}C$ to $75^{\circ}C$. When ferric and ferrous sulfates were used together, the synthetic conditions to get single phase magnetite became simpler than when ferrous sulfate was used alone because of the co-existence of $Fe^{2+}$ and $Fe^{3+}$ in the solution.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.798-807
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• 2008

Due to economic impairment derived from metal corrosion of pumping station installed around coastal area, it was needed for related cause-effect to be investigated for understanding practical corrosion behavior and providing proper control. This research was thus carried out to determine whether the microbe can influence on metal corrosion along with its control in the laboratory. For this study, groundwater was sampled from the underground pump station(i.e. I Gas Station) where corrosion was observed. Microbial diversity on the samples were then obtained by 16S rDNA methods. From this, microbial populations showing corrosion behaviors against metals were reported as Leptothrix sp.(Iron oxidizing) and Desulfovibrio sp.(Sulfur reducing) Iron oxidizing bacteria were dominantly participating in the corrosion of iron, while sulfate reducing bacteria were more preferably producing precipitate of iron. In case of galvanized steel and stainless steel, iron oxidizing bacteria not only enhanced the corrosion, but also generated its scale of precipitate. Sulfate reducing bacteria had zinc steel corroded greater extent than that of iron oxidizing bacteria. In the inactivation test, chlorine or UV exposure could efficiently control bacterial growth. However as the inactivation intensity being increased beyond a threshold level, corrosion rate was unlikely escalated due to augmented chemical effect. It is decided that microbial corrosion could be differently taken place depending upon type of microbes or materials, although they were highly correlated. It could be efficiently retarded by given disinfection practices.