• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.1-8
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• 2004

This study has been investigated to analyze the thermal stability of cesium reacted with fly ash with changing mole ratio of Cs/Al in hydrogen atmosphere. When the $CsNO_3$ and fly ash were reacted at $1000^{\circ}C$ in hydrogen atmosphere, cesium $nepheline(CsAlSiO_4)$ Phase began to emerge in addition to $pollucite(CsAlSi_2O_6)$ phase when the cesium loading quantity was greater than $0.32(g-Cs_2O/g-fly\; ash)$. Cesium $nepheline(CsAlSiO_4)$ Phase increased with increasing cesium loading quantity. When cesium trapped on a fly ash was exposed to $1200^{\circ}C$ in hydrogen atmosphere, no weight loss due to the volatilization was shown until the cesium loading quantity was reached at $0.32(g-Cs_2O/g-fly\; ash)$. In the case of the cesium loading quantity of $0.48-0.74(g-Cs_2O/g-fly\;ash)$ in hydrogen atmosphere, the weight loss increased with increasing the cesium loading quantity. This is considered to be due to the cesium $nepheline(CsAlSiO_4)$ whose vapor pressure is higher than that of $pollucite(CsAlSi_2O_6)$.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.445-451
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• 1987

Coagglutination method is widely used for the diagnosis of Salmonella infection. This test, however, has a disadvantage of false positive reaction due to the coagglutination of staphylococci with non-specific immune complexes or anti-staphylococci antibody in serum. Salmonell O antigen was detected by enzyme immunoassay with protein A-bearing Staphylococcus aureus as in the solid phase. Horse radish peroxidase was labeled to IgG specific against Salmonella O antigen. This enzyme immunoassay was much more sensitive than conventional coagglutination method without false poitive agglutination. To improve the sensitivity for detection of Salmonella O antigen in samples, we tried to determine the optimal concentration of normal IgG that inhibits non-specific binding of horse radish peroxidase labeled IgG to staphylococci, and to establish the optimal condition of reaction between antigen-antibody complex and staphylococci. Non-specific binding of horse radish peroxidase labeled specific IgG to staphylococci was almost blocked when the enzyme labeled IgG was 500-fold diluted with phosphate buffered saline containing 2mg/ml of normal IgG. When staphylococci coated with antibody to Salmonella O antigen were mixed with antigen-antibody complex and then incubated for 1 hour at room temperature, the minimal detectable concentration of Salmonella O antigen was 1ng/ml. The sensitivity of enzyme immunoassay was 100-fold greater than a conventional coagglutination method. This enzyme immunoassay could be expected as an improved method for detection of other infectious agents.

• BMB Reports
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• v.44 no.11
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• pp.758-763
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• 2011

Immunostimulatory CpG-DNA targeting TLR9 is one of the most extensively evaluated vaccine adjuvants. Previously, we found that a particular form of natural phosphodiester bond CpG-DNA (PO-ODN) encapsulated in a phosphatidyl-${\beta}$-oleoyl-${\gamma}$-palmitoyl ethanolamine (DOPE) : cholesterol hemisuccinate (CHEMS) (1 : 1 ratio) complex (Lipoplex(O)) is a potent adjuvant. Complexes containing peptide and Lipoplex(O) are extremely useful for B cell epitope screening and antibody production without carriers. Here, we showed that IL-12 production was increased in bone marrow derived dendritic cells in a CpG sequence-dependent manner when PO-ODN was encapsulated in Lipoplex(O), DOTAP or lipofectamine. However, the effects of Lipoplex(O) surpassed those of PO-ODN encapsulated in DOTAP or lipofectamine and also other various forms of liposome-encapsulated CpG-DNA in terms of potency for protein antigen-specific IgG production and Th1- associated IgG2a production. Therefore, Lipoplex(O) may have a unique potent immunoadjuvant activity which can be useful for various applications involving protein antigens as well as peptides.

• Mineral and Industry
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• v.25
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• pp.1-10
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• 2012

In this present work, the froth flotation of lithium ore from Boam mine located in Wooljin, Kyungbuk has been carried out to produce high-grade lithium concentrate. The sample ore-Lepidolite mainly contained silicate mineral (quartz, muscovite) and calcite. In consequences of the experiment, it has been possible to obtain relatively high-grade lithium while using anionic acid (oleic acid) to remove calcite before the froth flotation for lithium concentrate. Among the amines collectors (Armac-T, Armac-C, Armafloat-18, Armafloat-1597), Armac-T has been relatively effective than another ones. Under the optimum condition (collector : Armac-T 100g/t, frother : AF65 50g/t, depressants : $Na_2SiO_3$ 600g/t and Lactic acid 100g/t, pulp density : 20%, pH 5.5, number of cleaning : 2), it has been obtained relatively high-grade lithium concentrate ($Li_2O$) with recovery of 80.3% and with grade of 4.33%.

• Korean Journal of Materials Research
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• v.20 no.9
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• pp.472-477
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• 2010

$Al_2O_3$ has received wide attention with established use as a catalyst and growing application in structural or functional ceramic materials. On the other hand, the boehmite (AlO(OH)) obtained by sol-gel process has exhibited a decrease in surface area during phase transformation due to a decline in surface active site at high temperature. In this work, $Al_2O_3$-CuO/ZnO (ACZ) and $Al_2O_3$-CuO/CeO (ACC) composite materials were synthesized with aluminum isopropoxide, copper (II) nitrate hemi (pentahydrate), and cerium (III) nitrate hexahydrate or zinc (II) nitrate hexahydrate. Moreover, the Span 80 as the template block copolymer was added to the ACZ/ACC composition to make nano size particles and to keep increasing the surface area. The ACZ/ACC synthesized powders were characterized by Thermogravimetry-Differential Thermal analysis (TG/DTA), X-ray Diffractometer (XRD), Field-Emmision Scanning Electron Microscope (FE-SEM), Bruner-Emmett-Teller (BET) surface analysis and thermal electrical conductivity (ZEM-2:M8/L). An enhancement of surface area with the addition to Span 80 surfactant was observed in the ACZ powders from 105 $m^2$/g to 142 $m^2$/g, and the ACC powders from 103 $m^2$/g to 140 $m^2$/g, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.5
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• pp.217-222
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• 2007

Microwave dielectric properties of $(1-x)CaWO_4-xYNbO_4$ ceramics have been investigated as a function of $YNbO_4$ content($0.05{\leq}x{\leq}0.4$). A single phase with tetragonal scheelite structure was obtained up to x=0.10 and then the secondary phase with fergusonite structure was increased. With the increase of $YNbO_4$ content, apparent densities of the specimens were decreased. This results were due to the lower theoretical density of $YNbO_4(5.581g/cm^3)$ than that of $CaWO_4(6.117g/cm^3)$. Dielectric constant(K) and quality factor(Qf) were decreased with $YNbO_4$ content which could be attribute to the decrease of density and the increase of secondary phase. Temperature coefficient of resonant frequency (TCF) of the specimens with the $YNbO_4$ content was depended on dielectric mixing rule.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.223-229
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• 2010

In this study diverse dehydrogenative polymers (DHPs) were synthesized with three precursors of native lignin [p-coumaryl alcohol (PCA), coniferyl alcohol (CA), sinapyl alcohol (SA)] in the presence of horseradish peroxidase (HRP, EC. 1.11.1.7)/$H_2O_2$. To compare the structural features between DHPs and native lignin, the DHPs as well as pine/poplar milled wood lignins were simultaneously subjected to gel permeation chromatography (GPC) to determine average molecular weights and derivatization followed by reductive cleavage (DFRC) to investigate the frequency of ${\beta}$-O-4 linkage. The highest yield of DHP was measured to 71% when CA was solely injected (G-DHP) and the yield of H-DHP was 42%. However, single injection of SA could not form any polymer in this system. The average molecular weights of DHPs were ranged between 3,000~4,700, which were only 1/2 fold compared with that of pine MWL (G-type lignin: Mw 7,340) and 1/3 scale compared with that of poplar MWL (GS-type lignin: Mw 13,250). DFRC analysis revealed that the formation of ${\beta}$-O-4 linkage during dehydrogenative polymerization was the highest in the GS-DHP with ca. 502 ${\mu}mol$/g, which was, however, remained to only 50% compared to that in poplar MWL (1107 ${\mu}mol$/g). The ${\beta}$-O-4 linkage was estimated to ca. 286 ${\mu}mol$/g In the G-DHP, which was twice as much as that of H-DHP(127 ${\mu}mol$/g). Similar to GS-DHP, only half amount of ${\beta}$-O-4 linkage, compared to pine MWL, was formed during in vitro polymerization of CA by horseradish peroxidase/$H_2O_2$.

• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.509-516
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• 2003

A model system for the immnunochemical detection of Escherichia coli O157:H7 using a combined immunomagnetic separation (IMS) and test-strip liposome immunoassay (LIA) procedure was developed. Immunomagnetic beads coated with anti-E. coli O157 IgG antibodies were used to separate the E. coli O157 (including the H7 serotype) from culture. Immunoliposomes, whose surface was conjugated to goat anti-E. coli O157:H7 IgG and which encapsulated the marker dye, sulforhodamine B, were used as a detection label. The test strip, onto which antibodies to goat IgG were immobilized, was the immunosensor capturing immunoliposomes that did not bind to E. coli O157:H7 on the immunomagnetic bead-E. coli O157:H7 complexes. In experiments, pure cell culture suspensions of $10^5 E.$ coli O157:H7 organisms per ml produced a measurable signal inhibition, whereas a weak yet detectable signal inhibition occurred with $10^3CFU/ml$. The inhibition signals increased, when the incubation time for IMS was extended to 90 min and higher IgG-tag density (0.4mol%) was used on the liposomes. With 0.2 and 0.4mol% IgG-tagged liposomes, the IMS-LIA procedure showed more improved signal inhibitions than those of a direct (no IMS) LIA. The combined assay, which measures the instantaneous signal from immunoliposomes, can be completed within 90 min, making it significantly faster than conventional plating methods and enzyme-linked immunosorbent assay (ELISA). Accordingly, it is quite feasible to use the combined immunoassay format of IMS and dye-loaded immunoliposomes for the detection of E. coli O157:H7.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.2
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• pp.108-112
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• 2003

The calculated and measured dielectric constants of (1-x)(A $l_{1}$2/ T $a_{1}$2/) $O_2$-x(M $g_{1}$3/ T $a_{2}$3/) $O_2$ (0$\leq$x$\leq$1.0) solid solutions were investigated by variations of ionic polarizability and crystal structure. (A $l_{1}$2/ T $a_{1}$2/) $O_2$ and (M $g_{1}$3/ T $a_{2}$3/) $O_2$ were orthorhombic and tetragonal trirutile structure, respectively. When (A $l_{1}$2/ T $a_{1}$2/) $O_2$ was substituted by (M $g_{1}$3/ T $a_{2}$3/) $O_2$, the phase transformed to tetragonal structure over 60 mole. Because the total ionic radius of [(Mg+2Ta)/3]$^{4+}$ was slightly bigger than one of [(Al+Ta)/2]$^{4+}$, the lattice parameters increased with an increase of (M $g_{1}$3/ T $a_{2}$3/) $O_2$ substitution. The measured dielectric constant increased with an increase of (M $g_{1}$3/ T $a_{2}$3/) $O_2$ substitution and coincided with dielectric mixing rule and the calculated dielectric constant with the molecular additivity rule. There were some differences between the measured and the calculated dielectric constant. The reason of the lowered dielectric constant comparing with the calculated one was compressed stress due to the electronic structure of tantalum.

• Proceedings of the KAIS Fall Conference
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• 2011.12a
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• pp.196-199
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• 2011

In this study we synthesized mesoporous carbon supported CuO by using mesoporous silica i.e. SBA-15 as the template and cupric nitrate trihydrate ($Cu(NO_3)_23H_2O$)as copper source. The porous CuO was characterized with XRD, TGA, SEM and BET. The result reveals porous CuO has good crystal structure with uniform size of spherical crystal particles. The surface are a ($S_{BET}$) of porous CuO was found to be $153.46m^2g^{-1}$ with a total pore volume ($V_p$)of$0.1516cm^3g^{-1}$ and average pore size of 3.9 nm which was much higher than that of commercial CuO ($S_{BET}$, $7.6m^2g^{-1}$; $V_p$, $0.01cm^3g^{-1}$). The obtained porous CuO was studied for adsorption of $CO_2$and the maximum $CO_2$ adsorption capacity was found to be 67.5 mg/g of the sorbent at $25^{\circ}C$.