• The Korean Journal of Ecology
• /
• v.17 no.2
• /
• pp.131-141
• /
• 1994

One-year-old yellow-poplar (Liriodendron tulipifera L.) and sweetgum (Liquidambar styraciflua L.) seedlings were exposed to 0.10 ${\mu}l/l\;O_3$and simulated acid rain at pH 3.0 for ten consecutive weeks. Shoot height growth (SHG), fresh weight (FWT), dry weight (DWT), apparent plastochron duration (APD) and foliar nutrient concentrations were measured. None of growth measurements, except the apparent plastochron duration (APD), were significantly affected by any treatment in yellow-poplar seedlings. APD was approximately 30% higher in seedlings exposed to $0.1{\mu}l/l\;O_3$ ＋ pH 5.6 solution than any other treatment. Ozone significantly reduced SHG of sweetgum seedlings by 24% at the end of the ten-week fumigation. There were also significant effects of single and combined effects of ozone and simulated acid rain on APD in sweetgum. APD was significantly increased by 19.8% and 25.7% in seedlings exposed to $0.1{\mu}l/l\;O_3$ and pH 5.6 solution, respectively, and resulted in 46.1% higher APD in seedlings exposed to $0.1{\mu}l/l\;O_3$ + pH 5.6 solution compared with seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 solution. Phosphorus and sulphur were significantly greater in seedlings exposed to simulated rain at pH 3.0 compared with pH 5.6 for both species. Foliar S concentration was higher in seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 than in seedlings exposed to any other treatment in sweetgum. Ozone significantly increased Ca in sweetgum seedlings, however, ozone reduced Ca in yellow-poplar. Ozone also reduced S and Mg in sweetgum seedlings.

• Journal of Food Hygiene and Safety
• /
• v.33 no.1
• /
• pp.71-76
• /
• 2018

Norovirus is a leading cause of sporadic pathogenic non-bacterial gastroenteritis worldwide. For the detection of norovirus, reverse transcription real-time PCR (RT qPCR) has quickly become a major tool due to its sensitivity and specificity. However, accurate viral RNA extraction methods are essential for RT qPCR analysis. TRIzol reagents are used to extract RNA from biological materials and are therefore widely used for norovirus RNA extraction. In this study, the yield of viral RNA extraction using TRIzol from genogroup II (GII) among the human norovirus genogroup I (GI) and GII, and murine norovirus (GV) depended on the pH of the virus sample solution. The yield of RNA extraction was higher at the alkaline pH than in the acidic region compared with the Ct (threshold cycle) value of the real-time PCR. From the results of this study, it was found that the pH condition is very important for the quantitative analysis of norovirus by extracting GII RNA using TRIzol.

• The Research Journal of the Costume Culture
• /
• v.13 no.2 s.55
• /
• pp.240-247
• /
• 2005

In this study, cotton fabric specimens were pre-mordanted using Sn, Al, Cu, Cr, and Fe, and subsequently dyed using cochineal, maintaining the pH of the dye bath constant using pH buffer solutions of 4, 5, 6, 7, and 8. In the cases of Al, Cr, and Sn mordanting, the dye-uptake was well accomplished in the acidic range of pH 4 and 5. However, the dye-uptake was not accomplished in the range over pH 6. In the cases of Cu and Fe mordanting, however, the pH value did not affect the dye-uptake and the dyeability in the alkaline range was not decreased remarkably. In the case of non-mordant, the dye-uptake was not accomplished at all, and the Cu and Fe mordanting gave rise to the best dyeability. In the cases of non-mordanting and Al, Cu mordanting, there was no change in the $\lambda_{max}$, and in the cases of Sn and Cr mordanting, the $\lambda_{max}$ moved toward the shorter wavelength. In the case of Fe mordanting only, the $\lambda_{max}$ moved gradually toward the longer wavelength, and due to the pH effect deep-dyeing effect was revealed.

• Polymer(Korea)
• /
• v.31 no.3
• /
• pp.184-188
• /
• 2007

Monodisperse PMMA/HDDA polymer particles were coated via electroless Ni plating using sodium hypophosphite as a reducing agent in an acidic environment. In this study, the effects of 1) the pretreatment conditions, 2) the plating temperature, 3) the plating pH, and 4) the initial pH, control of plating bath on the variation of plating rate, surface state of plated particles and plating reproducibility were investigated. It was observed that every pretreatment steps, especially conditioning and acceleration step, were very important for obtaining uniform Ni plating and the plating rate was increased with the increase of plating temperature and pH. Moreover, the initial pH control of plating bath was critical for the plating reproducibility.

• Macromolecular Research
• /
• v.17 no.2
• /
• pp.99-103
• /
• 2009

We evaluated the efficacy of pH-sensitive micelles, formed by methoxy poly(ethylene glycol)-b-poly($\beta$)-amino ester) (PEG-PAE), as carriers for paclitaxel (PIX), a drug currently used to treat various cancers. PTX was successful encapsulated by a film hydration method. Micelles encapsulated more than 70% of the PTX and the size of the PTX-encapsulated micelles (PTX-PM) was less than 150 nm. In vitro experiments indicated that the micelles were unstable below pH 6.5. After encapsulation of PTX within the micelles, dynamic light scattering (DLS) studies indicated that low pH had a similar demicellization effect. An in vitro release study indicated that PTX was slowly released at pH 7.4 (normal body conditions) but rapidly released under weakly acidic conditions (pH 6.0). We demonstrated the safety of micelles from in vitro cytotoxicity tests on HeLa cells and the in vivo anti-tumor activity of PTX-PM in B16F 10 tumor-bearing mice. We concluded that these pH-sensitive micelles have potential as carriers for anti-cancer drugs.

• Polymer(Korea)
• /
• v.26 no.5
• /
• pp.551-558
• /
• 2002

It was observed that adsorption characteristics of sulfonated fabric ion-exchanger for separating nickel ion from electroplating rinse water. Swelling ratio was increased by increasing degree of sulfonation and polarity of solvent. Ion-exchange capacity was also increased by increasing degree of sulfonation and showed 3.38 meq/g at 16% sulfonated ion-exchanger. There was little effects of pH. Adsorption equilibrium was attained within 10 min, and adsorption rate was 7.5 mg/min. Adsorption capacity was not changed after 7 cycles of regeneration process. Regeneration adsorption capacity was slightly decreased to 2.01 meq/g. It confirmed that durability of sulfonated fabric ion-exchanger was suitable for adsorption process. Adsorption equilibrium time was linearly increased by increasing L/D and adsorption capacity showed the ion exchange capacity within the range of 2.71 ∼ 3.01 meq/g in continuous process. Design of adsorption column could be possible for L/D<2. Under constant L/D condition, there is no little pH effect when rinse water is acidic solution, and operation condition of adsorption process was optimized under pH 5.

• BMB Reports
• /
• v.28 no.2
• /
• pp.184-190
• /
• 1995

Functional study of the gap junction channel has been hindered by its inaccessibility in situ. Identification of forms of this channel in artificial membrane has been elusive because of the lack of identifying channel physiology. Connexin32 forms gap junction channels between neighboring cells in rat liver. Connexin32 was affinity-purified using a monoclonal antibody and reconstituted into artificial phospholipid vesicles. The reconstituted connexin32 formed channels through the vesicle membrane that were permeable to sucrose (Stokes radius: $5{\AA}$). The permeability to sucrose was reversibly reduced by acidic pH. In addition, the pH effect on the permeability to sucrose fit well with by the Hill's equation (where, n=2.7 and pK=6.7).

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.2
• /
• pp.306-307
• /
• 2011

Two phases of experiment were conducted to produce compost using sewage sludge and sawdust as mixing materials to determine their chemical properties and the performance of selected test crops. The first phase was done to produce compost as potting media and the second phase was done to test the efficacy of the produced compost. With regard to some chemical properties of the compost, pH was moderately acidic (5.11 to 5.58) while the OM, N, P, and K contents of the compost were 23.8-35.9, 1.12-1.56, 254.9-555.7, and 40.4-62.6, respectively.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
• /
• 2005.10a
• /
• pp.329-333
• /
• 2005

ACE inhibition activity of peptides was measured after 2 months of storage at $4^{\circ}C$ under condition of pH 6.0, 6.5, 7.0, 7.5, 8.0. and the ACE inhibitory activity were changed only slightly. After 2 months of chilled storage ($4^{\circ}C$), no dramatic change and significance was found. This indicates that acidic, neutral, weak alkali conditions did not affect ACE inhibitory activity of those peptides. Among peptide 1134, 1152, and 1155, peptides from thermolysin + protease A hydrolysates, inhibition activity of peptide 1134 and 1152 was decreased significantly at $60^{\circ}C$, however, they showed stable inhibition activity from $70^{\circ}C$ to $100^{\circ}C$ (P<0.001). Also, chromatogram of peptide 1134, 1152, and 1155 was shown that retention time of peptide of $60^{\circ}C$ was not correspond to the retention time of the rest of peptides. This indicated that temperature may change the inhibitory activity and profile of peptides.

• The Korean Journal of Mycology
• /
• v.32 no.2
• /
• pp.125-129
• /
• 2004

A carboxymethyl cellulase (CMCase) bas been isolated and purified from Lampteromyces japonicus. The molecular weight of CMCase was estimated to be 42 kDa by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The maximum activity of the purified CMCase was observed at pH 6.0 and $30^{\circ}C$, and stable for pH 4 to 7 to maintain 40% activity. The CMCase activity was activated by $Al_{2}(SO_{4})_{3}$, and inhibited by SDS. Also, the enzyme activity was decreased by the addition of ethylene diamine tetraacetic acid (EDTA), suggesting that the purified CMCase is metalloenzyme.