• Journal of Energy Engineering
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• v.20 no.2
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• pp.84-89
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• 2011

In this study, individual(alkaline, ultrasonic) and combined(alkaline+ultrasonic) pretreatment effect on sewage sludge solubilization was investigated. COD solubilization rates increased with the dose of NaOH added: solubilization reached 27.6%. Additional alkaline agents did not increase solubilization further. Ultrasonic pretreatment achieved 33~39% solubilization when 140 W/L amplitude. In(alkaline(pre-treatment)+ultrasonic (after-treatment)) treatment, solubilization increased as the combined intensity in creased($70.4{\pm}9.4%$). SCOD rising rate(0.076) was achieved.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.175-179
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were analyzed for their physicochemical charateristics and the compositions. Specific gravity, refractive index and yellowness of ERBO was higher than ARBO but smoking point was 60-$80^{\circ}C$ higher than ERBO. The free fatty acid content was 0.05% a ARBO and 0.88-1.36% ERBO. The wax was not detected in ARBO but the soft and hard waxes were detected in ERBO. The lipids were composed of 98-99% neutral lipid, 0.2-0.5% glycolipid and 0.1-0.5% of phospholipid in all samples. The triglyceride content of neutral lipid was 96.3% ARBO and 93.0-94.1% ERBO, and its monoglyceride content was 0.11% ARBO and 0.39-0.69% ERBO. The major fatty acid composition of samples were 41-42% oleic, 36-40% linoleic and 17-18% of palmitic acid.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.229-234
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• 2012

Disinfecting contaminated swine manure with FMD (Foot-and-Mouth Disease) and pathogenic viruses is very important for maintaining sanitized environment. However, very few research reported on this subject, especially post-disinfection to utilize the wastes as a renewable resource. This research is carried out to obtain basic information for chemical treatment in FMD SOP (Standard Operating Procedure, Korea) of contaminated swine manure. Using lime, sodium hydroxide, citric acid and hydrochloric acid, described in FMD SOP, the effects of chemical treatments on livestock manure were compared in this paper. Four combinations of alkali-acid treatments and four kinds of acid-alkali combinations were tested to find out the effective method. Total coliform bacteria in contaminated swine manure, $1.6{\times}10^4$ CFU/100 ml, decreased to the range of 1/1000~1/100 in all treatments. Some specific disinfectants increases BOD (Biochemical Oxygen Demand) and EC(Electric Conductivity), especially, alkaline treatments increases ammonia level than acid treatments. These findings suggest that the treatment methods should be considered as an important environmental factor in post-disinfection of contaminated animal manure with pathogenic microorganisms.

• Journal of Korea Foresty Energy
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• v.20 no.1
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• pp.62-72
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• 2001

To elucidate the behaviors of alkali swelllng of woods. the dimensional change in cross section of cell elements of four major Korean woods during alkali swelling were examined by an optical microscory, an imaging analysis method and an X-ray diffrartion During alkali swelling, tracheid diameter of Larix kaempferi wood showed greater swelling property than that of Pinus koraiensis wood, and the cell wall swelled highly over 10% sodium hydroxide solution treatment. The radial diameter of vessel elements in earlywood shrunk, but it swelled slightly in tangential direction. When treated with 5% NaOH, the wall thickness of wood fiber increased about three times over the original one. The thickness of cell wall in all elements and the diameter of wood fiber and tracheid showed almost isotropic shrinkage. The diameter of cell elements during the mercerization process decreased, but cell wall thickness Increased. Crystal transformation of cellulose in wood was not occurred by alkali treatments. but relative crystallinity and crystallite width of the woods increased slightly. Consequently, it was demonstrated that the swelling properties of woods were dependant on wood species, cell elements and alkali concentration.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.425-430
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• 2002

Physicochemical properties of chicken feet gelatin produced under acidic and alkaline conditions were investigated. Amino acid content of chicken feet gelatin was different from that of commercial gelatin due to the differences in raw materials and production process. Yield and hardness of chicken feet gelatin reached maximum at 24 h under acidic condition and at 1 week under alkaline condition, respectively. As the soaking period increased, viscosity and clarity increased under acidic condition, while decreased under alkaline condition. Color of the acid-treated chicken feet gelatin gel was more desirable than that of the alkali-treated on based upon L, a, b values. From gel permeation chromatography of the chicken feet gelatin, 12 subunits were detected. The amount of high molecular weight subunits, which is related to viscosity and hardness, of the alkali-treated chicken feet gelatin was twice as much as that of the acid-treated one.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.5
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• pp.690-695
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• 2016

This study was performed to evaluate the effect of alkaline treatment on Styela clava tunic (SCT). Considerable damage to the surface of alkali-treated SCT was observed by scanning electron microscopy (SEM) in a concentration-dependent manner upon alkaline treatment. The amount of crystalline region in SCT gradually increased with increasing NaOH concentration, which was analyzed by X-ray diffraction and thermogravimetric analysis. The initial enzymatic reaction of Celluclast toward SCT was elevated by treatment with NaOH up to 1.0 N concentration due to disruption of the SCT surface by promoting binding of enzymes with SCT. However, in the late stage of the enzyme reaction, hydrolysis rate decreased with elevation of NaOH concentration, thereby increasing the amount of non-reacted residuals. This result was due to the increase in the crystalline regions in SCT.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.222-230
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• 2009

This study was to investigate the effect of alkali treatment for long kenaf fiber to improve fiber surface characterics by removal of wax, lignin and hemicellulose which affect adversely for matrix union. SEM observation was also studied to check out the interface adhesion improvement by the alkali pre-treatment. From the result, interface coherence increased by 3% alkali pre-treatment and reached a maximum by 5% alkali pre-treatment. However, the 3% the bio-composites treated with 3% alkali was highest tensile and flexural strength than other.

• Journal of Korea Foresty Energy
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• v.18 no.2
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• pp.70-77
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• 1999

The behaviors of alkali swelling in four major Korean woods were examined as a function of concentration cf alkali solution. Density of alkali-treated woods increased highly with increasing alkali concentration in both softwoods and hardwoods. Wood samples swelled in dimension during alkali swelling, and thereafter they shrank highly by water washing and air drying. The air-dried wood samples after alkali treatment showed almost isotropic shrinkage in tangential and radial direction.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.180-185
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• 1985

The alkali refined rice bran oil (ARBO) and the esterified rice bran oil (ERBO) with glycerol were compared for their thermal stabilities at $150^{\circ}C$ and $180^{\circ}C$, respectively. The acid value gradually increased in ARBO during heating period but increased slowly in ERBO-2 and declined gradually in ERBO-1. The peroxide value was somewhat fluctuated during heating period, and the maximum peroxide value in all samples was 13.3 meq/kg. TBA value was sharply increased for the first 10 hr. heating and slowed down thereafter for all samples but ERBO were intensely colored after the heat treatment. The TG ratio of the oils after 90 hr. heating was not different at $150^{\circ}C$ but ERBO was 2-7% higher ratio of TG than ARBO at $180^{\circ}C$. The oxidative stability of ARBO was twice higher than ERBO according to the result of active oxygen test.

• Journal of Adhesion and Interface
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• v.20 no.3
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• pp.87-95
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• 2019

In the present study, the effect of alkali treatment of rice straw on the flexural properties and impact strength of rice straw/recycled polyethylene composite was investigated. Alkali treatments were performed by means of two different methods at various sodium hydroxide (NaOH) concentrations. One is static soaking method and the other is dynamic shaking method. The composites were made by compression molding technique using rice straw/recycled polyethylene pellets produced by twin-screw extrusion process. The result strongly depends on the alkali treatment method and concentration. The shaking method done with a low concentration of 1 wt% NaOH exhibits the highest flexural and impact properties whereas the soaking method done with a high concentration of 10 wt% NaOH exhibits the highest properties, being supported qualitatively by the fiber-matrix interfacial bonding of the composites. The properties between the two highest property cases above-described are comparable each other. The study suggests that such a low concentration of 1 wt% NaOH may be used for alkali treatment of natural fibers to improve the flexural and impact properties of resulting composites, rather than using high concentrations of NaOH, 10 wt% or higher. Considering of environmental concerns of alkali treatment, the shaking method is preferable to use.