• Korean Journal of Clinical Laboratory Science
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• v.47 no.2
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• pp.83-89
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• 2015

Although Mycobacterium tuberculosis complex strains remain responsible for the majority of diseases caused by mycobacterial infections worldwide, the increase in HIV (human immuno deficiency virus) infections has allowed for the emergence of other non-tuberculous mycobacteria as clinically significant pathogens. M. tuberculosis was detected by two-tube nested polymerase chain reaction (PCR) and non-tuberculous mycobacteria was detected by PCR-restriction fragment length polymorphism (RFLP) with Msp I. Result of niacin test is equal to result of two-tube nested PCR after culture for M. tuberculosis. In this study, acid fast bacilli stain (AFB. stain) >2+ case, Detection of Mycobacteria is similar to result before culture and after culture. AFB. stain <1+ case, result of mycobacteria is distinguished. Conclusionly, these results suggest that identification of mycobacteria must go side by side both culture and PCR for more fast and accuracy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.3
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• pp.264-268
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• 2002

Three types of polymer, a photoalignment material based N- (phenol)maleimide were synthesized and the liquid crystal (LC) aligning capabilities on the photopolymer layer were studied. A good LC alignment with UV exposure on the PMI5CA(N-(phenol)maleimide with 5-carbon chain cinnamoyl group) can be obtained. However, the LC alignment defects were observed on the PM13CA (N-(phenol)maleimide with 3-carbon chain cinnamoyl group) and PMIF (N-(phenyl)maleimide including fluoro cinnamoyl group). Also, the good LC alignment with UV exposure on the PM15CA surface was observed at until $150^{\circ}C$ of annealing temperature. The LC aligning ability on the photopolymer layer based N-(phenol)maleimide depends on the side chain length of photopolymer.

• Food Science and Preservation
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• v.10 no.4
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• pp.466-469
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• 2003

To develope corrugated paperboard box for cold chain system, it was investigated to compression strength and size of air hole. The size of air holes of the side tested box were designed as six groups, 4, 7, 10% and two kind of air hole, 2, 3 hole per the side. Compression strength of box(440${\times}$330${\times}$170 mm(length${\times}$width${\times}$height))was tested by compression tester UM-20Y, DaeSin Co., Korea, speed is 12.5 mm/min), it was stored 4 week at room temperature, RH 70${\times}$5%. Compression strength was high the mort narrow, the longer of air hole. Compression strength of box of the side, 4% was 10% higher among 4, 7, 10%, but differentiate of compression strength owing to the number of air hole was below 10%. for improving the compression strength of box, paper board box for cold chain system was made of the narrow of width and of the long length of air hole.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.549-554
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• 2002

Thermosensitive poly(organophosphazenes) bearing methoxy-poly(ethylene glycol) (MPEG) and alkylamines as substituents have been synthesized and characterized by elemental analysis, NMR spectroscopy, GPC, and DSC. All the polymers exhibited crystallinity, which was probably induced by the MPEG side chain of the polymers. All the polymers exhibited the lower critical solution temperature (LCSTs) in the range of 28 to $94^{\circ}C$ depending on several factors such as mole ratio of the substituents, kinds of PEG and alkylamines. The higher content of MPEG and shorter chain length of alkylamines of the polymers afforded the higher LCST. The LCSTs of the polymers exhibited almost concentration-independent behavior in the range of 3-30 wt % of the polymers in aqueous solutions. The polymers showed the higher LCSTs in the acidic solutions than in the neutral and basic solutions. The ionic strength of the polymer solution affected the LCST, which decreased with increased NaCl concentration. The polymer bearing almost equimolar substitutuents with the -N-P-N- unit has shown the LCST more sensitive to NaCl and pH than that with the -N-P-O- unit. The polymers were found to degrade in acidic solution but be very stable in alkali solution as well as in the buffer solution of pH 7.4.

• Journal of the Korean Applied Science and Technology
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• v.37 no.6
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• pp.1627-1634
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• 2020

In this study, water-based acrylic adhesives as copolymers with acrylic acid, 2-hydroxyethyl acrylate were synthesized using ethyl acrylate, 2-ethylhexyl acrylate, and lauryl methacrylate as the main monomers. Prepared water-based acrylic adhesive was compared to physical properties such as solid content, average particle size distribution, initial adhesive force, maximum adhesive force, peel strength, and heat resistance.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.1-5
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• 1998

The dispersing behaviors of oligomer-type anionic surfactants, cooligomers of diethyl maleate(CmD-Na) or maleic anhydride (CmM-Na) and $C_4{\sim}C_{16}$ alkyl vinylether, which have a different alkyl chain length of the hydrophobic group or degree of polymerization, were studied on the aqueous suspension of ${\alpha}-$ and ${\beta}-$ copper phthalocyanine and carbon black particles. In case of the side alkyl chain length of $C_4{\sim}C_{10}$ of CmD-Na, the dispersing actions were good in the concentration range of 0.01 to 0.1%. Especially, side alkyl groups played an important role in the orientation adsorption on the surface of pigment particles, and oligomers having smaller degrees of polymerization were more effective in the dispersing action, but did not affect the dispersability of carbon black.

• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.29-39
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• 2018

Vibrio vulnificus needs various responsive mechanisms to survive and transmit successfully in alternative niches of human and marine environments, and to ensure the acquisition of steady energy supply to facilitate such unique life style. The bacterium had genetic constitution very different from that of Escherichia coli regarding metabolism of glycogen, a major energy reserve. V. vulnificus accumulated more glycogen than other bacteria and at various levels according to culture medium and carbon source supplied in excess. Glycogen was accumulated to the highest level in Luria-Bertani (3.08 mg/mg protein) and heart infusion (4.30 mg/mg protein) complex media supplemented with 1% (w/v) maltodextrin at 3 h into the stationary phase. Regarding effect of carbon source, more glycogen was accumulated when maltodextrin (2.34 mg/mg protein) was added than when glucose or maltose (0.78.1-14 mg/mg protein) was added as an excessive carbon source to M9 minimal medium, suggesting that maltodextrin metabolism might affect glycogen metabolism very closely. These results were supported by the analysis using the malP (encoding a maltodextrin phosphorylase) and malQ (encoding a 4-${\alpha}$-glucanotransferase) mutants, which accumulated much less glycogen than wild type when either glucose or maltodextrin was supplied as an excessive carbon source, but at different levels (3.1-80.3% of wild type glycogen). Therefore, multiple pathways for glycogen metabolism were likely to function in V. vulnificus and that responding to maltodextrin might be more efficient in synthesizing glycogen. All of the glycogen samples from 3 V. vulnificus strains under various conditions showed a narrow side chain length distribution with short chains (G4-G6) as major ones. Not only the comparatively large accumulation volume but also the structure of glycogen in V. vulnificus, compared to other bacteria, may explain durability of the bacterium in external environment.

• Polymer(Korea)
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• v.25 no.2
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• pp.279-292
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• 2001

Two kinds of (hydroxypropyl)cellulose(HPCs) with different molar substitution (MS) and three types of derivatives based on the HPCs: (acetoxypropyl)celluloses, (ethoxypropyl)celluloses, and (cyanoethoxyprofyl)celluloses were synthesized, and their thermal and mesomorphic properties were investigated. All samples, which exhibit cholesteric reflection colours at room temperature, formed right-handed helicoidal structures whose optical pitches (λ$_{ms}$ ) increase with temperature. However, the isotropization ($T_{i}$) and glass temperatures, the magnitude of λ$_{m}$ of the mesophase at the same temperature, and the temperature dependence of λ$_{m}$ of the investigated derivatives highly depended on MS and the length and structure of the side chain introduced in HPC. The results were discussed in terms of the difference in the polarity and flexibility of the substituents and the distance between the main chains. For all derivatives, Am values approached infinity at temperatures above the $T_{i}$, of the mesophase, and no reversal in the sense of the pitch with temperature was detected.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.1-5
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• 1999

The dispersing performance of oligomer-type anionic surfactants ($C_mD-Na$), cooligomers of diethylester maleate and alkylvinylether of different alkyl chain lengths or polymerization degree were studied on the aqueous suspension of iron dxide or titanium dioxide particles which are hydrophilic pigments. The dispersion behavior of oligomer-type surfactants for these dispersoids, although anion charges on the surface of pigments particles showed different dispersing properties, was dependent upon the side alkyl chain length. Oligomer-type surfactants having more than $C_8$ side alkyl chain exhibited large dispersing action for relatively hydrophobic ${\alpha}-Fe_2O_3$ and Anatase $TiO_2$ in the concentration range of more than 0.1% oligomer-type surfactant solutions.

• Polymer(Korea)
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• v.33 no.1
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• pp.58-66
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• 2009

The thermotropic liquid crystalline behavior of the homologous series of cellulose tri[4-{4'-(nitrophenylazo) phenoxycarbonyl}] alkanoates (NACEn, n=2$\sim$8, 10, the number of methylene units in the spacer) have been investigated. All of the homologoues formed monotropic nematic phases. The isotropic-nematic transition temperature ($T_{iN}$) decreased when n is increased up to 7, but it became almost constant when n is more than 7. The plot of transition entropy at $T_{iN}$ against n had a sharp negative inflection at n=7. The sharp change at n=7 may be attributed to the difference in arrangement of the side groups. The melting temperature ($T_m$) and associated entropy change at $T_m$, in contrast with $T_{iN}$ and associated entropy change at $T_{iN}$, exhibited a distinct odd-even effect, suggesting that the average shape of the side chains in the crystalline phase is different from that in the nematic phase. The thermal stability and degree of order of the nematic phase observed for NACEn were significantly different from those reported for the homologous series of side-chain and combined type liquid crystal polymers bearing azobenzene or biphenyl units in the side chains. The results were discussed in terms of the differences in the chemical structure, the flexibility of the main chain, the mode of chemical linkage of the side group with the main chain, and the number of the mesogenic units per repeating unit.