• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.172-180
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• 1986

The Hammett's substituent constants were analyzed for the substituted-benzoic acid, -benzene and -naphthalene by LCAO MO method. Hammett's ${\sigma}$-values have been theoretically proved to treat as the sum of independent contribution of inductive effect and resonance effect. That is, Is (static inductive effect) and Id (dynamic inductive effect) corresponding to inductive effect are chosen as net charge and approximate self atom polarizability indices respectively, and ${\Delta}E^{HOMO}$ which is the difference in HOMO energy level between substituted molecule and unsubstituted molecule as resonance effect. In conclusion, it has been found that the observed ${\sigma}$-values depend on the sum of Id, Is and ${\Delta}E^{HOMO}$.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.236-243
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• 2009

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed throughout China, Mongolia and Siberia. This study was conducted to investigate an optimal condition for plant regeneration from mature seeds, leaf base segments, and root segments in L. chinensis. Plant growth regulators affecting embryogenic callus induction and plant regeneration were investigated by four-factor-three-level [L9 (34)] orthogonal test in this study. The effects of explants types (mature seeds, leaf base segments and root segments), callus types, medium types were examined in this study. Wild type (WT) and Jisheng No. 1 plants (JS) were used for primary callus induction. A clear explants difference was seen during callus induction; mature seeds were considered as the preferred explants; and the highest frequency of callus induction was obtained in Medium 6 using mature seeds as explants in WT. Plant regeneration ability was evaluated by frequencies of green callus forming, shooting, rooting, and shooting with roots. Effect of α-naphthalene acetic acid (NAA) on shoot regeneration was remarkable with the highest frequency of 70.8% in WT after 2-month culture. The medium with 0.2- 0.5 mg/L NAA was found to have the highest shoot induction. All regenerated shoots were successfully rooted when transferred on half-strength Murashige and Skoog (MS) basal medium. The acclimatized plantlets were grown to mature with flowering and seeds setting in green house conditions.

• BMB Reports
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• v.38 no.4
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• pp.407-413
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• 2005

Calcium and zinc binding protein, calprotectin is a multifunctional protein with broad spectrum antimicrobial and antitumoural activity. It was purified from human neutrophil, using a two-step ion exchange chromatography. Since surface hydrophobicity of calprotectin may be important in membrane anchoring, membrane penetration, subunits oligomerization and some biological roles of protein, in this study attempted to explore the effect of calcium in physiological range on the calprotectin lipophilicity. Incubation of human calprotectin ($50\;{\mu}g/ml$) with different calcium concentrations showed that 1-anilino-8-naphthalene sulfonic acid (ANS) fluorescence intensity of the protein significantly elevates with calcium in a dose dependent manner, suggesting an increase in calprotectin surface hydrophobicity upon calcium binding. Our study also indicates that calcium at higher concentrations (6, 8 and 10 mM) induces aggregation of human calprotectin. Our finding demonstrates that the starting time and the rate constant of calprotectin aggregation depend on the calcium concentration.

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.255-262
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• 1999

The new copolymers which contain flexible spacers in main chain were prepared and their properties were studied. the copolymers were synthesized in the melt polymerization melted from diacetoxynaphthalene isomers, ${\alpha},{\omega}bis(4-carboxyphenoxy)$ alkanes and p-acetoxy benzoic acid in the molar ratio of 1:1:2 and characterized for the effects of structure of naphthalenediol isomer moieties and the spacers on thermal crystalline and liquid crystalline properties of the resulting polymers. Diacetoxy naphthalene isomers were used 1. 5-,1. 6-,2. 6-and 2. 7-disubstituted ones and the spacers was either tetramethylene or decamethylene. The polymer was characterized by elemental and spectropic analysis, differential scanning calorimetry (DSC) on a polaring microscope, wide-angle X-ray diffractometry and thermogravimetry (TGA). There glass transition temperatures (Tg) and melting temperature (Tm) on the structure of the naphthalenediol isomer moieties and the length of the spacers. The presence of spacers was found to the helpful in crystallization of 1. 6-naphthalenediol copolyesters. The presence of amide group in the backbone chain of polymer was found to increase transition temperature, crystallization, thermal stability of polymers but to decreas solubility.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.288-292
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• 2003

We isolated a bacterium, K-19, which could degrade PAHs (polycyclic aromatic hydrocarbons) from a soil sample contaminated with PAHs. K-19 was cultured under the conditions where phenanthrene was a sole source of carbon and energy.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.466-470
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• 2003

Nine diarylheptanoids (1-9), one triterpene (10), one sesquiterpenoid (11), one naphthoquinone (12), four tetralones (13-16), one naphthalene carboxylic acid glucoside (17) and six naphthalenyl glycosides (18-23) were isolated from the roots of Juglans mandshurica Maximowicz (Juglandaceae), and their structures determined from the chemical and spectral data. Here, we report the inhibitory effects, on the DNA topoisomerases I and II activities, of all these compounds. Compounds 10 and 23 showed more potent inhibitory effects, on the DNA topoisomerases I and II (94.0 and 86.0% inhibitions at the concentration of 5 $\mu$ g/mL, respectively), than the positive control compounds, camptothecin and etoposide.

• Archives of Pharmacal Research
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• v.26 no.8
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• pp.653-658
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• 2003

It has been reported that at low temperature region, poloxamers existed as a monomer. Upon warming, an equilibrium between unimers and micelles was established, and finally micelle aggregates were formed at higher temperature. In this study, the fluorescence spectroscopy was used to study the micelle formation of the poloxamer 407 in aqueous solution. The excitation and emission spectra of pyrene, a fluorescence probe, were measured as a function of the concentration of poloxamer 407 and temperature. A blue shift in the emission spectrum and a red shift in the excitation spectrum were observed as pyrene transferred from an aqueous to a hydrophobic micellar environment. From the $I_1/I_3 and I_{339}/I_{333}$ results, critical micelle concentration (cmc) and critical micelle temperature (cmt) were determined. Also, from the fluorescence spectra of the probe molecules such as 8-anilino-1-naphthalene sulfonic acid and 1-pyrenecarboxaldehyde, the blue shift of the $\lambda_{max}$ was observed. These results suggest a decrease in the polarity of the microenvironment around probe because of micelle formation. The poloxamer 407 above cmc strongly complexed with hydrophobic fluorescent probes and the binding constant of complex increased with increasing the hydrophobicity of the probe.

• Analytical Science and Technology
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• v.19 no.3
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• pp.211-217
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• 2006

Diphenyl amine (DPA) was polymerized inside the channels of the mesoporous silica (MCM-41). MCM-41 (C) and MCM-41 (D) were prepared with cetyltrimethyl ammonium bromide (CTAB) and dodecyltrimethyl ammonium bromide (DTAB), respectively and used as hosts. Initially, the self assembly of DPA inside the pores of MCM-41 was made in ${\beta}$-naphthalene sulfonic acid (NSA) medium and subsequently poly (diphenylamine), PDPA was formed by oxidative polymerization. $N_2$ adsorption-desorption measurements of PDPA loaded MCM-41 (C) and MCM-41 (D) show variations in pore volume and surface area between them. A tubular form of poly (diphenylamine), PDPA was envisaged to form in the pores of MCM-41 and supported by high resolution transmission microscopy. The presence of PDPA inside the channel of MCM-41 was further confirmed by FTIR spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.62-62
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• 2022

Freesia has been an important worldwide cut flower because of its fragrance, long vase life and the wide color range of the flower. The conventional propagation methods by seeds and corms have many disadvantages such as shorter inflorescences with fewer numbers of florets, a reduction in cut flower quality and the accumulation of plant viruses in corms by successive cultivation. Therefore, the conventional propagation systems in Freesia needs to be replaced with tissue cultures to overcome the disadvantages. This study explored an efficient multiplication protocol using the combination of plant growth regulators (PGRs) for developed cultivar 'Sunny Gold'. The combination between 6-benzylaminopurin (BA) and α-naphthalene acetic acid (NAA) did not produce new shoots but developed enlarged roots. BA only treatments and the combination between BA and kinetin treatments were effective on shoot multiplication. The highest average number of shoots was 5.3 in the presence of 3 mg/L BA and 0.5 mg/L kinetin. To produce corms and cormlets, proliferated shoots were subcultured on 1/2 Murashige and Skoog (MS) medium supplemented with 90 g/L sucrose, 1 g/L charcoal and 7 g/L plant agar and placed at 4℃ in the dark for 6 months. The small size of corms and comlets were produced. The average number of regenerated comlets was 2.75 per shoot. The results showed that shoot multiplication is more efficient than cormlet regeneration for in vitro freesia proliferation.

• Journal of Soil and Groundwater Environment
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• v.18 no.1
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• pp.67-77
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• 2013

To improve the energy efficiency of conventional thermal treatment, soil remediation with microwave has been studied. In this study, the remediation efficiency of contaminated soil with semi-volatile organic contaminants were evaluated with microwave oven and several additives such as water, formic acid, iron powder, sodium hydroxide (NaOH) solution, and activated carbon. For the experiment, loamy sand and sandy loam collected from Imjin river flood plain were intentionally contaminated with hexachlorobenzene and phenanthrene, respectively. The contaminated soils were treated with microwave facility and the mass removals of organic contaminants from soils were evaluated. Among additives that were added to increase the remediation efficiency, activated carbon and NaOH solution were more effective than water, iron powder, and formic acid. When 10 g of hexachlorobenzene (142.4 mg/kg-soil) or phenanthrene (2,138.8 mg/kg-soil) contaminated soil that mixed with 0.5 g iron powder, 0.5 g activated carbon and 1 ml 6.25 M NaOH solution were treated with microwave for 3 minutes, more than 95% of contaminants were removed. The degradation of hexachlorobenzene during microwave treatments with additives was confirmed by the detection of pentachlorobenzene and tetrachlorobenzene. Naphthalene and phenol were also detected as degradation products of phenanthrene during microwave treatment with additives. The results showed that adding a suitable amount of additives for microwave treatments fairly increased the efficiency of removing semi-volatile soil organic contaminants.