• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.15-26
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• 2017

Cobalt ferrocyanide (CoFC) or nickel ferrocyanide (NiFC) magnetic nanoparticles (MNPs) were fabricated for efficient removal of radioactive cesium, followed by rapid magnetic separation of the absorbent from contaminated water. The $Fe_3O_4$ nanoparticles, synthesized using a co-precipitation method, were coated with succinic acid (SA) to immobilize the Co or Ni ions through metal coordination to carboxyl groups in the SA. CoFC or NiFC was subsequently formed on the surfaces of the MNPs as Co or Ni ions coordinated with the hexacyanoferrate ions. The CoFC-MNPs and NiFC-MNPs possess good saturation magnetization values ($43.2emu{\cdot}g^{-1}$ for the CoFC-MNPs, and $47.7emu{\cdot}g^{-1}$ for the NiFC-MNPs). The fabricated CoFC-MNPs and NiFC-MNPs were characterized by XRD, FT-IR, TEM, and DLS. The adsorption capability of the CoFC-MNPs and NiFC-MNPs in removing cesium ions from water was also investigated. Batch experiments revealed that the maximum adsorption capacity values were $15.63mg{\cdot}g^{-1}$ (CoFC-MNPs) and $12.11mg{\cdot}g^{-1}$ (NiFC-MNPs). Langmuir/Freundlich adsorption isotherm equations were used to fit the experimental data and evaluate the adsorption process. The CoFC-MNPs and NiFC-MNPs exhibited a removal efficiency exceeding 99.09% for radioactive cesium from $^{137}Cs$ solution ($18-21Bq{\cdot}g^{-1}$). The adsorbent selectively adsorbed $^{137}Cs$, even in the presence of competing cations.

• Journal of Life Science
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• v.13 no.1
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• pp.90-98
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• 2003

An allium rhizobacterium Serratia plymuthica AL-1 was previously selected as a biocontrol agent of allium white rot. The chitinase from S. plymuthica AL-1 produced in medium containing colloidal chitin was purified by ammonium sulfate precipitation (40~70%), affinity adsorption, column chromatography on DEAE-sephadex A-50 and sephadex C-200 gel filtration. The enzyme was purified 10.8-fold with a yield of 7.3% from the starting culture broth. The purified chtinase gave a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis, it's molecular weight was estimated to be 55 kDa. The optimum pH and temperature of the purified enzyme were pH 5.5 and $55^{\circ}C$, respectively and it is stable up to $50^{\circ}C$ and maintains around 90% of its activity for 60min. The enzyme were activated by $Ca^{2+}$, $Mn^{2+}$ and $Mg^{2+}$ and inhibited by $Cu^{2+}$, SDS, $\rho$-CMB, MIA, respectively. The purified chitinase showed broad spectrum of antifungal activities against plant pathogenic fungi Sclerotium cepivoruin, Alternana alternnta, Colletotrichum glceosporioidrs, Phoma sp., Sclerotinia sclerotiorum, Stemphylium solani, Fusarium oxysporium f. sp. niveum but rarely inhibited Phytophthora capsici and Pythium ultimum.. The purified chitinase from S. plymuthica AL-1 caused swelling, lysis, deceleration and degradation of the hyphal tips of S. sczerotiorum causing allium white rot. It suggest that S. prymuthica AL-1 chitinase play an important part in the bifunctional chitinase / lysozyme activity.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.59-64
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• 2001

The effect of major operating parameters in spray drying sorber(=SDS) for automatic control for the simultaneous removal of acidic and organic gaseous pollutants from solid waste incinerator was performed. The field experiment was carried out in pilot scale test for the quantification of major operating parameters of hydrophilic and the hydrophobic pollutants. The removal efficiencies of $SO_2$and HCI in the 5wt% slurry condition were being increased with the increase of the stoichiometric ration which is the molecular ratio of lime to the pollutant concentration, and with the decrease of inflow flue gas temperature in the pilot SDS reactor. The removal efficiency along the height of spray drying sorber was closely related to the temperature profile, and more than 90% of total removal efficiency was achieved in an absorption region. For the removal of acidic gas the optimum operating condition considering the economics and a stable operation is the 5wt% of slurry concentration, 1.2 of stoichiometric ratio and 25$0^{\circ}C$ of inflow flue gas temperature. For the organic gases of benzene and toluene the removal efficiencies were 20-60% which is much lower than that of acidic gas. The best removal efficiency was obtained at 1.5 of stoichiometric ratio and 25$0^{\circ}C$ of inflow flue gas temperature. The organic\`s removal efficiency along the height of spray drying sorber was quite different from that of acidic gas, that is, more than 60% of the total removal efficiency for benzene and 90% of the total removal for toluene were achieved in the dried adsorption region, which was formed at the lower or exit part of the reactor.

• Journal of the Korean Chemical Society
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• v.6 no.2
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• pp.158-161
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• 1962

Three kinds of acid clay are chosen as samples; sample-I is the Korean acid clay, Sample-II is prepared by heating the mixure of the Korean acid clay with 20% $H_2SO_4$ for 4 hrs., and the sample-III, the reference sample, is the Japanes acid clay supplied by Katayama Chem. Co.. 15 samples are prepared by heating them at temperatures of $100^{\circ}C$, $300^{\circ}C$, $500^{\circ}C$, $700^{\circ}C$, and $900^{\circ}C$ for 6 hrs. separately.The adsorption experiments are carried out on these samples using bromphenol blue water soln.(conc., 0.001%) as adsorbate. It is found that the degree of decoloration depends upon the temperature of thermal treatment, i.e., the higher the temperature the lower the degree of decoloration is. At any specified temperature of thermal treatment, the degree of decoloration is in following order: sample II>sample I>sample III.The X-ray photographs of the samples show that the intensities of a few specified lines decrease with increasing temperatures of thermal treatment.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.451-456
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• 1994

Alkyl polyglucosides (APG), so called natural nonionic surfactants, are prepared with glucose from corn starch and fatty alcohol from palm and/or coconut oil. When we studied on interfacial properties of APG, surface and interfacial tension, cmc, foaming and effectiveness, according to degree of polymerization of glucose unit (D.P.=1.2~1.8) and alkyl chain length, the former hardly affects but the latter greatly affects on them. The order of detergency for fatty acid soils decreased as followings ; APG 0814> APG 1214> APG 10> APG 0810> APG 08, and the samples with lowest interfacial tension and maximum adsorption had a better detergency.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.47-51
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• 2006

Modern residing equipment developed much quantitatively along with economic growth but improvement for agreeable residing space of indoor environment is insufficient situation yet. Also, the latest sick-building syndrome discharging room contaminant such as Formaldehyde, toluene, radon etc. built house or buildings newly human body threaten. Radon of them is real condition that raise origination of lung cancer next to smoke. So, wish to in this research by one of solution way of these problems adsorption performance and specie performance excellent activated carbon to concrete bricks for deconstipating suppository that is room finish fare mix and examine closely after grasp physical, mechanical special quality, hazardous substance and specie performance effect. According to result that estimate environment efficiency evaluation, the $CO_2$ absorption amount displayed decrease effect more than about 90% in activated carbon metathesis rate 40% and radon release amount displayed tendency that decrease about $76{\sim}96%$ in activated carbon metathesis rate 40%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.135-136
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• 2020

Recently, there is a problem that is most important in constructing buildings and building materials. It is a harmful substance generated in buildings. These harmful substances are CO₂, radon and formaldehyde, volatile organic compounds generated from building materials. These are bad for the human body, may have a negative effect and cause large illnesses such as cancer. Recently built apartments have a high density, so there is a problem that harmful substances do not escape well. As a result, people's interest in indoor air quality is growing and in order to solve this problem and various researches are being conducted on the materials used for concrete pouring to find out how much the materials used adsorb harmful substances. this study uses carbon black as a material that can adsorb these harmful substances. The purpose of this study is to measure the bending strength, compressive strength, and to determine whether the paste containing carbon black can improve indoor air quality.

• Analytical Science and Technology
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• v.20 no.1
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• pp.55-60
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• 2007

A sensitive technique for the determination of trace Cu(II) in various samples after the column preconcentration by adsorbing its N-benzoylphenylhydroxylamine (BPHA) onto benzophenone was developed. Several experimental conditions such as the pH of the sample solution, the amount of chelating agent, the amount of benzophenone, and the flowrate of sample solution and so forth were optimized. The interfering effects of diverse concomitant ions were investigated. Fe(III) and $CN^-$ interfered with more seriously than any other ions. However, the interference by these ions could be overcome sufficiently by adjusting the added volume of 0.01M BPHA to 10 mL. The dynamic range, the correlation coefficient ($r^2$) and the detection limit obtained by this proposed technique were 5.0~120 ng/mL, 0.9974, and 2.1 ng/mL, respectively. For validating this proposed technique, the aqueous samples (stream water, reservoir water, and wastewater), the plastic sample and the diluted brass sample were used. Recovery yields of 93~102% were obtained. These measured data were not different from ICP-MS data at 95% confidence level. This method was also validated by the rice flour CRM (normal, fortified) samples. Based on the results from the experiment, it was found that this proposed technique could be applied to the determination of Cu(II) in various real samples.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.969-973
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• 1999

In this work, we studied the degree of hydrolysis of ion exchanger in $NH_4OH$ solution and sorption characteristics of $NH_3$ by potentiometric titration curves with using carboxylic acid ion exchanger Fiban K-4. We knew that the theoretical pH values agreed with the experimental pH values on the $NH_4OH$ concentrations in various concentrations of supporting electrolyte $(NH_4)_2SO_4$. The sorption values of $NH_3$ using the ion exchanger can be calculated from equivalent sorption curves for various pH. Also, the degree of hydrolysis increased with decreasing concentration of supporting electrolyte and pH. In order to obtain the mono ion form below 0.01 M as the decreasing concentration of supporting electrolyte, the pH values should be increased. From these results, therefore, the concentrations of supporting electrolyte and pH values were determined.

• Polymer(Korea)
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• v.25 no.3
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• pp.311-317
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• 2001

In this study, we synthesized bead-type GMA-DVB copolymer using glycidylmethacrylate (GMA) with high reactivity and hydrophilicity. Macrorecticular anion exchanger containing the trimethylammonium group were then prepared by amination with trimethylammonium chloride. We observed that the size of $NO_3^-$ is smaller than that of $SO_4^{2-}$ which disturb $NO_3^-$ removal in most of coexistent anions in ground water. Thus we investigated selective affinity for $NO_3^-$ and properties of individual ion exchangers with various DVB content. For each resins, we confirmed formation of copolymer by FT-IR spectrometer and investigated ion exchange capacity, swelling ratio, the amination yield and the effect with degree of crosslinking on adsorbability for nitrate. When amount of DVB is 4 wt%, amination yield, ion exchange capacity and swelling ratio was 384.3%, 3.25 meq/g and 77.1%, respectively. In these result, it can found that synthetic optimal condition is 4 wt% DVB content for monomer.