• Title/Summary/Keyword: iron and manganese

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Effect of pH and Iron/Manganese Ion on TiO2 Mediated Photocatalytic Inactivation of Index Microorganisms (LNAPL을 이용한 지중 산소전달 향상: (I) Abiotic Condition)

  • Ha, Jeong-Hyub;Kang, Seon-Hong
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.3
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    • pp.307-311
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    • 2004
  • The objective of this work is to evaluate the hypothesis that a good technique for supplying oxygen to the saturated zone in the presence of light nonaqueous phase liquid (LNAPL) pool contamination at the water table is to pass air through the unsaturated zone above the pool. This hypothesis was evaluated in experimental studies performed using a bench-scale, sand-tank reactor, Steady-state abiotic experiments in the sand-tank reactor with air flowing through the reactor headspace demonstrated that oxygen supply through the water table interface into the saturated zone was enhanced when an LNAPL (dodecane) pool was present at the water table. These experimental results confirmed the hypothesis that an LNAPL pool can serve as a high concentration oxygen source to the oxygen-limited area beneath the pool and, as a result, enhance the in situ biodegradation rate.

Simultaneous Removal of SO$_2$ and NO by Using Metal Oxide( II ) -Oxidative Sorption of SO$_2$ by Metal Oxide- (금속산화물을 이용한 이산화황과 산화질소의 동시재거( II ) -금속산화물과 이산화황의 반응-)

  • 신창섭
    • Journal of the Korean Society of Safety
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    • v.6 no.4
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    • pp.26-33
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    • 1991
  • To remove SO$_2$ from flus gas, cupric oxide, manganese oxide and iron oxide were studied with varying loading value. The experiment was carried out in a flow reactor and the reactants were prepared by impregnation method using alumina. The reaction temperature was varied from 30$0^{\circ}C$ to 45$0^{\circ}C$. Experimental results showed that all of these metal oxides were effective on SO$_2$ removal reaction and cupric oxide was the best reactant. The sample with 10wt% loading value was better reactant than with 20wt% because in case of 20wt% loading, metal dispersion on the alumina surface was not uniform. And the SO$_2$ removal efficiency was increased with the reaction temperature.

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Origin of Spherule Samples Recovered from Antarctic Ice Sheet-Terrestrial or Extraterrestrial?

  • Sekimoto, Shun;Kobayashi, Takayuki;Takamiya, Koichi;Ebihara, Mitsuru;Shibata, Seiichi
    • Nuclear Engineering and Technology
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    • v.48 no.2
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    • pp.293-298
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    • 2016
  • Thirty-eight spherules from the Antarctic ice sheet were analyzed using neutron activation analysis under two different conditions to investigate their origin. In almost all of these spherules, the contents of iron, cobalt, and manganese were determined to be 31% to 88%, 17 mg/kg to 810 mg/kg, and 0.017% to 7%, respectively. A detectable iridium content of 0.84 mg/kg was found in only one spherule, which was judged to be extraterrestrial in origin. A comparison of elemental compositions of the Antarctic spherules analyzed in this study with those of deep-sea sediment spherules and those of terrestrial materials revealed that most of the Antarctic spherules except for the sample in which iridium was detected could not be identified as extraterrestrial in origin.

Influence of Cotton Pre-Treatment on Dyeing with Rubia cordifolia extracts for Cotton (면의 전처리 방법이 Rubia cordifolia 추출물의 염색성에 미치는 영향)

  • Bum Hoon Lee
    • Textile Coloration and Finishing
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    • v.35 no.1
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    • pp.1-7
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    • 2023
  • In this study, the influence of pre-treatment(bleaching, mercerization by liquid ammonia and caustic soda) on cotton fabrics were investigated on dyeing Rubia cordifolia extracts. Aluminium Sulfate, Iron(Ⅱ) Sulfate Heptahydrate, Copper(Ⅱ) Sulfate Pentahydrate, Tin(Ⅱ) Sulfate, Manganese(Ⅱ) Chloride Tetrahydrate were used as mordanting agents. K/S value and washing fastnesses of the dyed cotton fabrics pretreated under different conditions were investigated. The K/S values were increased in the order of bleaching, liquid ammonia and mercerization pre-treatment. It was found that the pre-treatment conditions did not significantly affect the color change. The colorfastness to washing of most of all dyed fabrics were over grade 4 regardless of pre-treatment condition.

Effect of Subclinical Mastitis on Milk of Cross Bred Sahiwal × Jersey Cows: A Biochemical Study

  • Kalorey, D.R.;Kurkure, N.V.;Nigot, N.K.;Patil, M.P.;Pathak, V.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.3
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    • pp.382-383
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    • 2001
  • The experiment was undertaken to study the effect of subclinical mastitis on the biochemical parameters of milk in crossbred (Sahiwal $\times$ Jersey) cows. Subclincial mastitis was judged using California Mastitis Test and graded on a scale of 0 to 2. Twenty six milk samples of each grade were subjected to somatic cell count. Separated milk whey was analysed for total protein, immunoglobulin and trace mineral content. Results indicate linear increases in somatic cell count, total protein and immunoglobulin concentrations in milk with increase in grade of subclinical mastitis. However, copper, zinc, manganese and iron concentration in milk was not affected by grade of mastitis.

False Positive SOD Activity of Bifidobacterium spp. Grown in MRS Medium

  • Chang, Woo-Suk;So, Jae-Seong
    • Journal of Microbiology and Biotechnology
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    • v.8 no.4
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    • pp.305-309
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    • 1998
  • The superoxide dismutase (SOD) activity of seven Bifidobacterium spp. strains was examined by an indirect SOD assay method. Some Bifidobacterium spp. showed significant levels of SOD activity. However, we could not observe any significant differences between anaerobic and aerobic cultures. Furthermore, although several Bifidobacterium spp. exhibited some degree of tolerance to paraquat which produces superoxide radicals, the apparent SOD activity of these strains was not correlated with their resistance to paraquat. In addition, when we added increasing amounts of manganese or iron to MRS medium which had been prepared without either of the metal ions, the apparent SOD activity of cell free extracts (CFEs) was increased with increasing concentration of both metal ions. To our surprise, the heat-denatured CFEs also showed nearly identical correlative patterns. Based on these results, the apparent SOD activity was likely due to a nonenzymatic dismutation. These results strongly suggest that high concentration of divalent metal ions ($Mn^{2+}$, $Fe^{2+}$) in MRS medium result in nonenzymatic dismutation which can lead to false positive SOD activities in Bifidobacerium spp.

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The Sintering Behaviour of Fe-Mn-C Powder System, Correlation between Thermodynamics and Sintering Process, Mn Distribution, Microstructure

  • Hryha, Eduard;Dudrova, Eva
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.839-840
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    • 2006
  • Sintering behavior of the Fe-0.8Mn-0.5C powder system was studied on the specimens with a density of ${\sim}7.0g/cc$ sintered at $1120^{\circ}C$ for 30 min in a gas mixture of $7%H_2/93%N_2$ with the inlet dew point of $-60^{\circ}C$. During the atmosphere monitoring ($CO/CO_2$-content and dew point) was showed, that carbothermical reduction occurs in two different temperature ranges; three peaks of dew point profile also can be distinguished during sintering cycle as well. Following sintering the Mn-content distribution and microstructures around the Mn-source were micro-analytical evaluated; the results showed that manganese travels through porous iron matrix up to ${\sim}60{\mu}m$.

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The Effect of Additives on the Characteristics of Piezoceramics PZT (PZT 특성에 미치는 각종 첨가물의 효과)

  • Lee, S.H.;SaGong, G.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.05a
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    • pp.109-112
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    • 1993
  • In this paper, We have studied about the microstructure of the piezoceramics PZT that were added with some kinds of additives, such as Niobium(Nb), Iron(Fe) or Manganese(Mn). The grain size of PZT ceramics was decreased with increasing the amounts of additive of Nb or Fe, while increased with increasing Mn. The curie temperature was changed slightly for the PZT ceramics containing $Fe^{3+}$, which is not dependent on the amounts, but $Nb^{5+}$ or $Mn^{2+}$ ion added PZT was lowered. The resistivity was increased with increasing the amounts of $Nb^{5+}$ additive, while decreased for $Mn^{2+}$ additive.

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The strategies for the supplementation of vitamins and trace minerals in pig production: surveying major producers in China

  • Yang, Pan;Wang, Hua Kai;Li, Long Xian;Ma, Yong Xi
    • Animal Bioscience
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    • v.34 no.8
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    • pp.1350-1364
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    • 2021
  • Objective: Adequate vitamin and trace mineral intake for pigs are important to achieve satisfactory growth performance. There are no data available on the vitamin and trace mineral intake across pig producers in China. The purpose of this study was to investigate and describe the amount of vitamin and trace minerals used in Chinese pig diets. Methods: A 1-year survey of supplemented vitamin and trace minerals in pig diets was organized in China. A total of 69 producers were invited for the survey, which represents approximately 90% of the pig herd in China. Data were compiled by bodyweight stages to determine descriptive statistics. Nutrients were evaluated for vitamin A, vitamin D, vitamin E, vitamin K, thiamine, riboflavin, vitamin B6, vitamin B12, pantothenic acid, niacin, folic acid, biotin, choline, copper, iron, manganese, zinc, selenium, and iodine. Data were statistically analyzed by functions in Excel. Results: The results indicated variation for supplemented vitamin (vitamin A, vitamin D, vitamin E, vitamin K, vitamin B12, pantothenic acid, niacin, and choline) and trace minerals (copper, manganese, zinc, and iodine) in pig diets, but most vitamins and trace minerals were included at concentrations far above the total dietary requirement estimates reported by the National Research Council and the China's Feeding Standard of Swine. Conclusion: The levels of vitamin and trace mineral used in China's pig industry vary widely. Adding a high concentration for vitamin and trace mineral appears to be common practice in pig diets. This investigation provides a reference for supplementation rates of the vitamins and trace minerals in the China's pig industry.

Sectional Composition of Minerals in Domestic Deer Antler (국내산 녹용(Cervi parvum Cornu) 의 부위별 무기질 조성)

  • Kim, Hye-Young;Rhyu, Mee-Ra
    • Korean Journal of Food Science and Technology
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    • v.32 no.1
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    • pp.31-36
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    • 2000
  • The mineral compositions were analysed of the tip and the upper section of dried domestic antlers. The upper section was divided longitudinally into four parts. The tip and the upper section were divided traversely into the velvet and the spongy bone layers. The contents of ash, calcium, phosphorus and magnesium increased (p<0.05), and those of manganese, zinc, copper and iron decreased (p<0.05) downward from the tip both in the velvet and the spongy bone layers. The contents of ash, calcium, phosphorus, manganese and zinc of the spongy bone layer were significantly (p<0.05) higher than those of the velvet layer. The tip, which is the growth center of the antler, had the significantly (p<0.05) lowest proportions of Ca/ash, Ca/P and Ca/Fe ratios both in the velvet and spongy bone layers.

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