• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.247-250
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• 1992

Effects of free alkali and moisture on sucrose polyesters (SPE)-possible non calorie fat substitute-synthesis were investigated using a model system composed of sodium oleate, sucrose, potassium carbonate and methyl oleate. Trace amounts of free alkali in sodium oleate were found to interefere with SPE synthesis. When free alkali content in sodium oleate was varied gradually from 0% to 5%(w/w), the yield of SPE production was reduced from 92% to 45.5%. The moisture absorbed in sodium oleate, sucrose and potassium carbonate during storage also interefered with SPE synthesis. The yield (92%) of SPE production with dried ($105^{\circ}C$.6 hrs) reactants and catalysts was higher than that (89%) of SPE production with non-dried. Soybean oil fatty acid sodium soaps (FASS) not containing free alkali could be manufactured with slightly less than molar ratio of sodium hydroxide to soybean oil fatty acid methyl esters (FAME). Practically, 91.7% yield of soybean oil SPE production was outcomed by minimizing free alkali and moisture which were remaining in sucrose, potassium carbonate, soybean oil FASS and soybean oil FAME.

• Medical Lasers
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• v.10 no.1
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• pp.22-30
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• 2021

Background and Objectives Ocular alkali burns cause severe damage to the ocular tissues and vision loss. Solcoseryl is a standardized calf blood extract that normalizes the metabolic disturbance and aids in maintaining the chemical and hormonal balance and has been used to treat burns in various tissues. This study examined the effects of Solcoseryl on a rat corneal alkali burn model. Materials and Methods Twenty rats were assigned randomly to four equal groups, including alkali burn, hyaluronic acid, Solcoseryl eyedrop, and Solcoseryl gel. A corneal alkali burn was induced by a NaOH-soaked paper disc. The treatments were given twice a day, every day. The wound area was measured after 24 and 48 hours, and the degree of neovascularization and corneal opacity were scored every week. The rats were sacrificed after three weeks for immunohistochemistry (IHC) to compare the level of inflammatory cytokines, IL-1β, IL-6, and TNF-α. The thickness of the retinal layers was compared to observe any changes in the retina. Results The use of Solcoseryl on corneal alkali burn accelerated wound healing with less neovascularization, greater opacity, and less cataract. IHC showed that the inflammation of the cornea was controlled by both the hyaluronic acid and Solcoseryl treatments. On the other hand, the inflammation had spread to the retina. When the dosage forms were compared, eyedrops were more effective on corneal inflammation, while the gel-type had a greater effect on retinal inflammation. Conclusion Solcoseryl was effective in accelerating the wound healing rate on a corneal alkali burn but could not prevent the spread of inflammation from the cornea to the retina. Eyedrops were more effective on inflammation in the cornea, and the gel was more effective in the retina.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.731-736
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• 2003

Alkali silicate system has wide application to accelerating admixture for shotcrete, but it has several problems that decrease long-term strength and delay setting time. So alkali-free system was gradually focused on accelerating admixtures for shotcrete due to its environmental property. The aim of this study is to investigate effect of alkali-free accelerating admixtures on aluminum sulfate system containing diethanolamine or acrylic acid etc. The alkali-free accelerating admixture has better properties than silicate system accelerating admixtures on compressive strength and low pH as shotcrete. Especially, the compressive strength of alkali-free accelerating admixture containing diethanolamine was increased about 10% compared with the value of ordinary portland cement.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.698-706
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• 1996

Dehydrogenation of methanol to produce formaldehyde was carried out over various silica-alumina catalysts doped with alkali metals in a continuous flow system. The reaction was rather dependent on Lewis acid than Br${\ddot{o}}$nsted acid suggesting that dehydrogenation of methanol was an electronic reaction. The Br${\ddot{o}}$nsted acid sites on silica-alumina were neutralized by doping with alkali metals, and the neutralization effect of Br${\ddot{o}}$nsted acid was dependent on the electron-donating capacity of the dopant metals. Activation energy for dehydrogenation of methanol decreased when Br${\ddot{o}}$nsted acid was neutralized by doping with K.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.6
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• pp.580-586
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• 2010

Acid and alkali pretreatments were applied to tofu processing waste (TPW) to increase the solubility of ingredients in TPW. Pretreatment at 1.0% of HCl and 2.5% of NaOH condition resulted in the increase of SCOD concentration from 3.2 g COD/L to 27 g COD/L and 33 g COD/L, respectively. The acid and alkali-pretreated TPW was studied for its fermentative $H_2$ production capacity in batch mode using a thermophillic mixed culture. Alkali pretreatment on presence of 2.5% NaOH exhibited more soluble portion released compared to acid pretreatment using HCl, however the $H_2$ production from acid pretreated TPW was better than alkali-pretreated TPW probably due to the sodium inhibition on microbial activity. In addition, sewage sludge was externally added to the acid-pretreated (1.0% HCl) TPW by 20% (on volume basis). Average H2 production rate was increased from 31 to 78 ml/L-broth/hr, and it was attributed to the high buffer capacity and abundant nutrients especially divalent cation in sewage sludge.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.58-64
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• 2008

Pretreatment of eliminating FFA is needed to make biodiesel from animal fat recovered from leather wastes because its acid value is high. This study was carried out to investigate the influence of 4 different pretreatment methods, which are heterogeneous catalyst method, ion exchange resin method, low pressure.high temperature method, and alkali method on the eliminating FFA and fatty acid composition. The results showed that the rate of eliminating FFA increased in the order of alkali method > catalyst method > low pressure high temperature method > ion exchange method. In the case of pretreatment of alkali method using NaOH, the rate of eliminating FFA appeared more than 86% regardless of acid value. Therefore, it was considered that alkali method using NaOH was the most effective in the view of economical and productive aspects, taking it into account that the acid value of animal fat recovered from fleshing scrap generated during leather making processes was 7 to 8.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.139-145
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• 1993

The nucleotide sequence of the xylanase gene (xynS) from alkali-tolerant Bacillus sp. YA.14 was determined and analyzed. A 639 base pairs open reading frame for xynS gene was observed and encoded for a protein of 213 amino acids with a molecular weight of 23, 339. S1 nuclease mapping showed that the transcription initiation site of the xynS gene did not exist in the cloned DNA. Ribosome binding site sequence with the free energy of -18.8 Kcal/mol was observed 8 base pairs upstream from the initiation codon, ATG. The proposed signal sequence consisted of 28 amino acids, of which 3 were basic amino acid residues and 21 were hydrophobic amino acid residues. When the amino acid sequences of xylanases were compared, Bacillus sp. YA-14 xylanase showed 48% homology with Bacillus sp. YC-335 xylanase and 96% homology with xylanases from B. subtilis and B. circulans.

• Advances in concrete construction
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• v.10 no.3
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• pp.221-236
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• 2020

To reduce the CO₂ emissions associated with the manufacture of portland cement (PC), an efficient alternative like an alkali-activated binder (AAB) is the requirement of the industry. To promote the use of AAB in construction activities, a practically implementable mix proportion is required. Owing to the several raw ingredients of AAB concrete and their associated uncertainties, partial replacement of PC by AAB may be adopted instead of complete replacement as per industrial requirements. Hence, the present study aims to determine an optimal proportion for partial replacement of PC with AAB and recommend a technique for it based on site conditions. Three modes of partial replacement are followed: combining all the dry ingredients for AAB and PC followed by the addition of the requisite liquids (PAM); combining the PC and the AAB concrete in two horizontal layers (PAH); and two vertical layers (PAV). 28-day old specimens are exposed to 10% v/v solutions of HCl, H₂SO₄, and HNO₃ to evaluate changes in mechanical, physical, and microstructural characteristics through compressive strength, corrosion depth, and microscopy. Based on deterioration in strength and integrity, PAH or PAV can be adopted in absence of acid attack, whereas PAM is recommended in presence of acid attack.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.2
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• pp.88-94
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• 2010

Cattail (Typha L.) was used as a raw material for producing both bio-ethanol and pulp for papermaking at the same time. Pretreatments of cattail stems and leaves with acid ($H_2SO_4$) and alkali (NaOH) in three different addition levels were studied before soda pulping. The acid pretreatment gave reducing sugar of 15.2% of initial weight, but alkali pretreatment close to 1%. Soda pulping of the pretreated cattail gave 3% reduction in pulp yield and less bonding properties in paper; however, refining of the pulp from the pretreated cattail with alkali restored their fiber bondings up to that of the pulp from no-pretreated cattail at equivalent freeness.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.1-8
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• 2014

BACKGROUND: Recent studies using many amendments for heavy metal stabilization in soil were conducted in order to find out new materials. But, the studies accounting for the use of appropriate amendments considering soil pH remain incomplete. The aim of this study was to investigate the effects of initial soil pH on the efficiency of various amendments. METHODS AND RESULTS: Acid soil and alkali soil contaminated with heavy metals were collected from the agricultural soils affected by the abandoned mine sites nearby. Three different types of amendments were selected with hypothesis being different in stabilization mechanisms; organic matter, lime stone and iron, and added with different combination. For determining the changes in the extractable heavy metals, water soluble, Mehlich-3, Toxicity Characteristic Leaching Procedure, Simple Bioavailability Extraction Test method were applied as chemical assessments for metal stabilization. For biological assessments, soil respiration and root elongation of bok choy (Brassica campestris ssp. Chinensis Jusl.) were determined. CONCLUSION: It was revealed that lime stone reduced heavy metal mobility in acid soil by increasing soil pH and iron was good at stabilizing heavy metals by supplying adsorption sites in alkali soil. Organic matter was a good source in terms of supplying nutrients, but it was concerning when accounting for increasing metal availability.