• Advances in environmental research
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• v.5 no.2
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• pp.141-151
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• 2016

Large amounts of aluminum hydroxide ($Al(OH)_3$) exist in water purification sludge (WPS) because of the added aluminum coagulant in water treatment process. Notably, $Al(OH)_3$ is an amphoteric compound, can be dissolved in its basic condition using sodium hydroxide to form aluminate ions ($Al(OH)_4{^-}$). However, in a process in which pH is increasing, the humid acid can be dissolved easily from WPS and will inhibit the recovery and reuse of the dissolved aluminate ions. This study attempts to fix this problem by a novel approach to separate $Al(OH)_4{^-}$ ions using nanofiltration (NF) technology. Sludge impurity in a alkaline solution is retained by the NF membrane, such that the process recovers $Al(OH)_4{^-}$ ions, and significantly decreases the organic matter or heavy metal impurities in the permeate solution. The $Al(OH)_4{^-}$ ion is an alkaline substance. Experimental results confirm that a recovered coagulant of $Al(OH)_4{^-}$ ion can effectively remove kaolin particles from slightly acidic synthetic raw water.

• Clean Technology
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• v.21 no.2
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• pp.108-116
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• 2015

Hydrogen sulfide and ammonia are one of the common malodorous compounds that can be found in emissions from many sewages treatment plants and industrial plants. Therefore, removing these harmful gases from emissions is of significance in both life and industry because they can cause health problems to human and detrimental effects on the catalysts. In this work, pyrolytic carbon blacks from waste tires were used to develop adsorbent with good adsorption capacity for removal of hydrogen and ammonia. Pellet-type adsorbents were prepared by a mixture of carbon black, metal oxide and sodium hydroxide or hydrochloric acid, and their adsorption capacities were estimated by using breakthrough curve of a continuous fixed bed adsorption column at ambient condition. The adsorbent manufactured with a mixture of carbon black, iron oxide(III) and sodium hydroxide showed the maximum working capacity of hydrogen sulfide. For ammonia, maximum working capacity was obtained by the adsorbent manufactured with a mixture of carbon black, copper oxide(II) and hydrochloric acid.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.223-230
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• 1990

Gelatinization properties of heat-moisture treated Olchal(japonica) and Hankangchalbyeo(j x indica) waxy rice starches were compared. The blue value, light transmittance of starch suspension and viscosity in sodium hydroxide solution were similar between two starches. Olchal starch showed lower water binding capacity, swelling power md peak viscosity by amylograph than Hankangchalbyeo starch. Upon heat-moisture treatments all above parameters were decreased. The critical sodium hydroxide concentration for gelatinization was increased by treatments. The initial pasting temperature of Olchal starch was higher than that of Hankarlgchalbyeo. All amylograph reference points increased by the treatments, except the maximum viscosity or 2l% moisture-treated Olchal starch. Starches treated at 18% moisture level showd the highest value of consistency index. The activation energy of consistency index for gelatinized Olchal starch was lower than that for Hankangchalbyeo starch. The heat-moisture treatments had no effect on activation energy.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.336-339
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• 2011

Algae is an abundant and potential fermentation substrate. The enzymatic hydrolysis of algae was investigated by pre-treating an alkaline hydrogen peroxide with commercial cellulase and viscozyme. Algae used in this study was the Ulva pertusa. The evaluated response was the yield of released glucose after the enzymatic hydrolysis. Alkaline hydrogen peroxide containing mixtures of 1 wt% hydrogen peroxide and 1~1.75 wt% sodium hydroxide was also used. The results show that the highest glucose conversion was obtained for Ulva pertusa using 5 wt% hydrogen peroxide at $60^{\circ}C$ for 3 h. The required amount of enzymes after the pre-treatment with alkaline hydrogen peroxide were reduced by far compared to that of untreated Ulva pertusa. Also, the amount of glucose that is released during the enzymatic hydrolysis was increased.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.6
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• pp.653-662
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• 2012

This study measured the effect of general pre-treatment on PLA fabrics to confirm the benefits of enzymatic processing on PLA fabrics in the textile industry as well as evaluated the hydrolytic activities of three lipases. The effects of lipase hydrolysis were analyzed through moisture regain, dyeing ability, tensile strength, and surface morphology. As a result, PLA fibers were easily damaged by a low concentration of sodium hydroxide and a low treatment temperature. The optimal treatment conditions of Lipase from Candida cylindracea were pH 8.0, $40^{\circ}C$, and 1,000 U. The optimal treatment conditions for Lipase from Candida rugosa were pH 7.2, $37^{\circ}C$, and 1,000 U. The optimal treatment conditions for Lipase from Porcine pancreas were pH 8.0, $37^{\circ}C$, and 2,000 U. The moisture regain and dyeing ability of PLA fabrics increased and the tensile strength of PLA fabrics decreased. The results of surface morphology revealed that there were some cracks due to hydrolysis on the surface of the fiber.

• Transactions on Electrical and Electronic Materials
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• v.10 no.3
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• pp.71-74
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• 2009

Electroplated Cu is a cost efficient metallization method in microelectronic packaging applications. Typically in 3-D chip staking technology, utilizing through silicon via (TSV), electroplated Cu metallization is inevitable for the throughput as well as reducing the cost of ownership (COO).To achieve a comparable film quality to sputtering or CVD, a pre-cleaning process as well as plating process is crucial. In this research, atmospheric plasma is employed to reduce the usage of chemicals, such as trichloroethylene (TCE) and sodium hydroxide (NaHO), by substituting the chemical assisted organic cleaning process with plasma surface treatment for Cu electroplating. By employing atmospheric plasma treatment, marginally acceptable electroplating and cleaning results are achieved without the use of hazardous chemicals. The experimental results show that the substitution of the chemical process with plasma treatment is plausible from an environmentally friendly aspect. In addition, plasma treatment on immersion Sn/Cu was also performed to find out the solderability of plasma treated Sn/Cu for practical industrial applications.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.201-206
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• 1984

In order to obtain an easy and effective scarification method for stimulating the seed germination of Korean lawn grass (Zoysia japonica Steud.), sodium hypochlorite (SH), which is used as a commercial bleach and a seed disinfestant, was tested as a chemical scarifier instead of potassium hydroxide (KOH). 1. Scarification with 4% SH for 2 hours followed by 8-hour water-rinse stimulated seed germination more effectively compared to generalized scarification method by KOH treatment. 2. The degree of stimulating seed gemination was different by the various water-rinsing time after SH treatment, but the optimum rinsing time was about 4 to 8 hours. 3. GA treatment after SH scarification stimulated seed germination. However, the stimulation effect of GA was not showed in non-scarified control. 4. SH treatment significantly decreased the percentage of the infection of microflora in seed samples compared to KOH treatment. 5. Under practical seed scarification conditions for stimulating germination of Korean lawn grass seed. SH may have advantages over KOH with respect to ease of preparing, securing and handling.

• Transactions on Electrical and Electronic Materials
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• v.4 no.4
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• pp.22-25
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• 2003

High series resistance due to the presence of glass frit is one of the major problems for screen printed silicon solar cells. Cells having electrical parameters below the prescribed values are usually rejected during solar module fabrication. Therefore, it is highly desirable to improve the electrical parameters of the silicon solar cells and thereby to increase the overall production yield. It was observed that, the performance of low quality mono-crystalline silicon solar cells made by standard screen printing technology could be improved remarkably by novel surface treatment. We have chemically treated the surface using sodium hydroxide (NaOH) and silver nitrate ($AgNO_3$) solutions. NaOH treatment helps to reduce the series resistance by decreasing the presence of excess glass frit on the top silver grid contact. The $AgNO_3$ treatment is used to reduce the series resistance comes from the deposition of silver on the grids by filling the holes present (if any) within the grid pattern.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.1
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• pp.1-6
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• 1990

The objective of this experiment was to compare the effect of pH-regulated alkaline hydrogen peroxide (AHP) treatment of rice straw with those of sodium hydroxide (NaOH) and anhydrous ammonia ($NH_3$) treatments on in sacco digestivility. Three non-lactating ruminally cannulated Holstein cows were fed a diet containing 90% forage and 10% concentrate on a dry matter (DM) basis. The AHP treatment significantly (p<0.05) reduced acid detergent lignin content of the straw, resulting in significant (p<0.05) increase of neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose concentrations. Disappearance rates of DM and NDF of the straw significantly (p<0.05) increased at the incubation time of 24 h. On the other hand, those of ADF and cellulose were significantly (p<0.05) higher at the incubation time of 12 h than those of the others. The effective degradability of DM(EDDM), NDF(EDNDF), ADF(EDADF) and cellulose (EDCE) were determined using in sacco nylon bag technique on the basis of 0.05/h solid outflow rate. The greater differences (p<0.05) of EDDM, EDNDF, EDADF and EDCE were found between AHP treated straw and the others. In general, AHP treatment of the straw recorded higher digestion coefficients than untreated straw as well as NaOH and $NH_3$ treated straws. The results of this study demonstrate that AHP treatment can be used as a effective method for improving the nutritive value of rice straw for ruminants.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.97-101
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• 1987

Physicochemical properties of heat-moisture (18, 21, 24 and 27%) treated naked barley (Youngsanbori) starch indicated that crystailinity of the starch was decreased upon treatment and water-binding capacity drastically increased as the moisture level increased. The swelling power was decreased, but the solubility increased by heat-moisture treatment. Apparent viscosity in aqueous sodium hydroxide solution was repressed as moisture-treatment level increased. Amylograph hot paste vicosities were decreased upon treatment except initial pasting temperature.