• Textile Coloration and Finishing
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• v.4 no.3
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• pp.65-73
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• 1992

To control the hydrolysis rate of PET fabric with NaOH, HCl and $CH_3$COOH(HAc), as regulating reagent, were added to the 0.5 M NaOH solution. The concentrations of acids in 0.5 M NaOH were varied. PET fabrics were treated with aqueous solutions of acids in 0.5 M NaOH under different conditions. The weight loss of PET fabric, the rate of hydrolysis, the apparent activation energy (E$_{\alpha}$), the handle value, the etched surface of treated PET fabric, and the effect of salts such as NaCl, $CH_3$COONa(NaAc), and NH$_4$Cl on the weight loss were discussed. Acids in the aqueous 0.5 M NaOH solution decreased the weight loss of PET fabric bacause of neutralization of OH- and the weight loss of PET fabrics treated with corresponding concentration of aqueous NaOH solution to the concentrations of the aqueous solutions of acids in 0.5 M NaOH was lower than that of PET fabrics treated with aqueous solutions of acids in 0.5 M NaOH. The addition of NaCl to aqueous NaOH solution accelerated the reaction of OH- with PET greatly, the addition of NaAc increased the weight loss slightly, but the addition of NH$_4$Cl decreased the weight loss. It was thought that the very remarkable result that NaCl in aqueous NaOH solution promoted the hydrolysis of PET with NaOH would contribute to the conservation of energy and NaOH in the weight loss finishing process of PET fabric. The etched surface and the handle value of treated PET fabric were independent of the difference in the kinds of acids and salts added.nd salts added.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E1
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• pp.23-35
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• 2005

Size distribution of particulate water-soluble ion components was measured at Gosan, Korea using a micro-orifice uniform deposit impactor (MOUDI). Sulfate, ammonium, and nitrate showed peaks in three size ranges; Sulfate and ammonium were of dominant species measured in the fine mode ($D_{p} < 1.8 {\mu}m$). One peak was observed in the condensation mode ($0.218\sim0.532{\mu}m$), and the other peak was obtained in the droplet mode ($0.532\sim1.8{\mu}m$). Considering the fact that the equivalent ratios of ammonium to sulfate ranged from 0.5 to 1.0 in these size ranges, it is inferred that they formed sufficiently neutralized compounds such as ($NH_{4})_{2}SO_{4} and (NH_{4})_{3}H(SO_{4})_{2}$ during the long-range transport of anthropogenic pollutants. On the other hand, nitrate was distributed mainly in the coarse mode ($3.1\sim6.2{\mu}m$) combined with soil and sea salt. Two sets of MOUDI samples were collected in each season. One sample was collected when the concentrations of criteria air pollutants were relatively high, but the other represented relatively clean air quality. The concentrations of sulfate and ammonium particles in droplet mode were the highest in winter and the lowest in summer. When the air quality was bad, the increase of nitrate was observed in the condensation mode ($0.218\sim0.282{\mu}m$). It thus suggests that the nitrate particles were produced through gas phase reaction of nitric acid with ammonia. Chloride depletion was remarkably high in summer due to the high temperature and relative humidity.

• Carbon letters
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• v.7 no.3
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• pp.171-179
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• 2006

A carbonaceous sorbent was prepared from rice husk via sulphuric acid treatment. After preparation and washing, the wet carbon with moisture content 85% was used in its wet status in this study due to its higher reactivity towards Cr(VI) than the dry carbon. The interaction of Cr(VI) and the carbon was studied and two processes were investigated in terms of kinetics and equilibrium namely Cr(VI) removal and chromium sorption. Cr(VI) removal and chromium sorption were studied at various initial pH (1.6-7), for initial Cr(VI) concentration (100 mg/l). At equilibrium, maximum Cr(VI) removal occurred at low initial pH (1.6-2) where, Cr(III) was the only available chromium species in solution. Cr(VI) removal, at such low pH, was related to the reduction to Cr(III). Maximum chromium sorption (60.5 mg/g) occurred at initial pH 2.8 and a rise in the final pH was recorded for all initial pH studied. For the kinetic experiments, approximate equilibrium was reached in 60-100 hr. Cr(VI) removal data, at initial pH 1.6-2.4, fit well pseudo first order model but did not fit pseudo second order model. At initial pH 2.6-7, Cr(VI) removal data did not fit, anymore, pseudo first order model, but fit well pseudo second order model instead. The change in the order of Cr(VI) removal process takes place in the pH range 2.4-2.6 under the experimental conditions. Other two models were tested for the kinetics of chromium sorption with the data fitting well pseudo second order model in the whole range of pH. An increase in cation exchange capacity, sorbent acidity and base neutralization capacity was recorded for the carbon sorbent after the interaction with acidified Cr(VI) indicating the oxidation processes on the carbon surface accompanying Cr(VI) reduction.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.8
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• pp.1010-1020
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• 2014

Ballast water effluent treated by an electrolytic method contains reactive chlorine species and disinfection by-products (DBPs). In this study, we conducted whole effluent toxicity (WET) testing and ecological risk assessment (ERA) to investigate its ecotoxicological effects on marine environment. WET testing was carried out for three marine pelagic organisms, i.e., diatom Skeletonema costatum, rotifer Brachionus plicatilis and fish Paralichthys olivaceus. The biological toxicity test revealed that S. costatum was the only organism that showed apparent toxicity to the effluent; it showed no observed effect concentration (NOEC), lowest observable effect concentration (LOEC) and effect concentration of 50% (EC50) values of 12.5%, 25.0% and 83.3%, respectively, at brackish water condition. In contrast, it showed insignificant toxicity at seawater condition. B. plicatilis and P. olivaceus also showed no toxicities to the effluent at the both salinity conditions. Meanwhile, chemical analysis revealed that the ballast water effluent contained total residual oxidants (TROs) below $0.03{\mu}g/L$ and a total of 20 DBPs including bromate, volatile halogenated organic compounds (VOCs), halogenated acetonitriles (HANs), halogenated acetic acids (HAAs) and chloropicrin. Based on ERA, the 20 DBPs were not considered to have persistency, bioaccumulation and toxicity (PBT) properties. Except monobromoacetic acid, the ratio of predicted environmental concentration (PEC) to predicted no effect concentration (PNEC) of the other 19 DBPs did not exceed 1. Thus, our results of WET testing and ERA indicated that the ballast water effluent treated by electrolysis and subsequently neutralization was considered to have no adverse impacts on marine environment.

• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.487-493
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• 2017

This study was conducted to propose measures of water quality management as the water criteria for waterscape facilities which have been highlighted as alternatives to wading pools in summer season was legislated. The number of public waterscape facilities has reached 290 sites in Gyeounggi province and 971 sites in South Korea in 2017. The water tank capacity of 80.3 % public waterscape facilities was less than $100m^3$. Facilities with disinfection system were only 6.5 % and facilities with filtration function were also very low at 6.9 %. Most of the waterscape facilities, about 93%, are expected to be vulnerable to complying with revised water quality criteria because they have to be disinfected by handling. Chlorine disinfectants, which are more persistent than ozone or ultraviolet sterilization methods, are more preferred. However, care should be taken when adding disinfectans because hypochlorous acid, which is an effective component of chlorine disinfectant, remains after the disinfection, but it is easily decomposed with time. For this study, ${\bigcirc}{\bigcirc}$ park floor fountain with a capacity of $63m^3$ was selected and the amount of free residual chlorine concentration was measured by injecting a certain amount of chlorine bleach. As a result, it took 5 hours to decrease from the water quality standard of 4 mg/L to 0.04 mg/L. If the waterscape facility is operated for 7 to 8 hours, the chlorine bleach should be re-injected after 5 hours. In addition, the problem of pH increase due to the input of chlorine disinfectant is expected, and the neutralization method using vinegar was proposed.

• KSBB Journal
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• v.11 no.1
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• pp.65-70
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• 1996

Sodium gluconate was produced by neutralization of gluconic acid formed during the submerged culture fermentation of glucose with Aspergillus niger ACM 7. The fermentation characteristics of Aspergillus niger ACM 7 were investigated quantitatively according to the change of the initial glucose concentrations and the initial pHs of fermentation broth. The maximum specific growth rate was estimated to be $0.20hr^{-1}$ at 95g/$\ell$ of initial glucose concentration. The maximum fermentability of sodium gluconate was 95% at the initial glucose concentration of 26g/$\ell$. However, the maximum sodium gluconate productivity was 1.18g/$\ell$/hr when the initial glucose concentration was 110g/$\ell$. The optimum pH was found to be 5.5 for both the cell growth and the sodium gluconate production. With optimized culture conditions, the productivity of sodium gluconate in a fed-batch culture(production fermentor, 16,000$\ell$) increased up to 7.1g/$\ell$/hr.

• Membrane Journal
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• v.28 no.4
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• pp.286-295
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• 2018

A novel multi-valent salt based on polyethyleneimine having molecular weight of 800 (PEI 800) has been synthesized and characterized as forward osmosis draws solute. A reaction intermediate was synthesized by the neutralization reaction of polyethyleneimine and methyl acrylate, and was hydrolyzed with potassium hydroxide to synthesize a water soluble carboxylic acid (potassium salt) polyethyleneimine. NMR spectrometry, viscometry measurements and osmometry measurements was performed to characterize the draw solute. Forward osmosis experiments were done to know whether the solute could be used as a draw solute or not. The result shows comparable water flux and lower reverse salt flux compared with NaCl as a draw solute. We have also demonstrated recycling of the draw solute in the FO-NF integrated process.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.83-92
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• 2005

Dissolution rate of minerals may differ from climates configuration, but weathering rate of feldspars is generally proved to be relatively higher The result of geochemical reaction modeling indicates the acid water of pH 4.5 excluding any other variables, was 2.3 times higher than that in ordinary rain of pH 5.7. This result proved that pH is very important factor in preservation of granite cultural properties. To prevent the weathering of stone cultural properties, weathering characteristics of stones should be studied first and constitution of dry environments, using water repellent or oil coating, isolating water which cause chemical weathering reaction like hydration and oxidization should be considered. Considering the long-term reactions between granite and rain, selection of materials, which can bring neutralization and non-oxidization conditions, are very important in using cleaning agents and biological controls.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.73-82
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• 1999

The objectives of this study are to investigate soil contamination in the vicinity of abandoned Au-Ag mine and to apply a remediation technique of liming to tailings. In the study area of the Imcheon Au-Ag mine, soils were sampled in and around the mine the analyzed by Atomic Absorption Spectrometry extracted by both 0.1N HCl and aqua regia. Elevated levels of Cd, Cu, Pb and Zn concentrations extracted by 0.1N HCl were found in soils taken from tailings site. These high contents directly influenced metal concentrations in soils taken in the vicinity of the site. This is mainly due to clastic movement by wind and effluent of mine waste water. In addition, relatively enriched concentrations of the metals were found in soils extrated by aqua regia due to strong decomposition of the samples compared with 0.1N HCl extration. According to the statistical approach, metal concentrations in soils by 0.1N HCl had a positive correlation with those by aqua regia extraction. Mine waste waters and stream waters were also sampled around the mine in spring and summer and analyzed by AAS for Cd, Cu, Pb and Zn, and by Ion Chromatography for anions. Like soils developed over tailings, significant levels of metals and sulphates were found in the mine waste waters ranging of 0.2~0.3, 0.5~2.0, 0.2~2.8, 30~50 and 1,240~4,700 mg/l of Cd, Cu, Pb, Zn and $SO_4^{2-}$, respectively. These elevated levels influenced in the stream waters in the vicinity of the tailings site. In seasonal variation of metal and anion contents, relatively high levels were found in waters sampled on summer due to leaching the metals and anions from tailings by rain. This study also examined the possibility of lime treatment for remediation of acid mine tailings and assumed to be 46 tones of pulverized lime for neutralization of the tailings.

• Journal of Pharmacopuncture
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• v.20 no.3
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• pp.173-178
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• 2017

Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science) and articles of peer-reviewed journals. Results:Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5'nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.