• Journal of the Korean GEO-environmental Society
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• 제17권3호
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• pp.13-19
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• 2016

The ultrasonic waves for monitoring concrete materials have been used to investigate the setting and hardening process of concrete. This paper presents the application of bender elements for monitoring the hardening properties of Controlled Low Strength Material (CLSM) and the characterization of shear waves in CLSM according to curing time. To ensure the early age properties and flow, the CLSM consists of CSA cement, sand, silt, water, fly ash, and accelerator. In addition, three different type specimens according to fine contents are mixed. A couple of bender elements are installed at the wall of measurement cell and the CLSM specimen are prepared at the measurement cell for 28 days. Experimental results show that the resonant frequency and shear wave velocities increase with an increase in the curing time, regardless of the fine contents. Up to ten hours, the amplitudes of shear waves also increase, and the resonant frequency and shear wave velocities at the same time increase as the fine contents increase. The shear wave measurement technique using the bender elements may be effectively used to evaluate the hardening properties of CLSM along the curing time.

• Applied Biological Chemistry
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• 제13권1호
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• pp.29-34
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• 1970

In order to prepare digested Protein source for the Weanling Food from soybean, an attempt was made to decompose steamed soybean protein to amino acids and peptides by protease and cellulase produced from Aspergillus niger and Aspergillus sojae. In this paper, the optimum condition for digestion of soybean protein were studied and also investigated the effects of decolorization of it. As the results, followings were obtained; 1. As steaming conditions, a treatment under 15 lb of pressure and 10 minutes of heating shows most effective. 2. The optimum pH of Asp, sojae enzyme for the digestion of soybean protein is 6.0, while that of Asp. niger enzyme is 4.4. In successievly-decomposing with Asp. sojae and Asp. niger, it shows the most effective on ratio of water-soluble-nitrogen to total nitrogen and amino-nitrogen to total nitrogen than any other separate treatments. 3. The suitable amount of the enzyme solution to that of the soybean substrate paste, in volume, is 1 : 2. 4. Digestion ratio of soybean protein indicates the gradual and steady effects of increasing time of digestion, but 8 hour-digestion regarding to putrefaction was suitable. 5. The most effective decolorization was successively passed on culumns of active carbon and anion exchanger (Dowex 2-x-8) at room temperature. In separate treatments, the effective order of decolorization was as follows; (Dowex 2-x-8)>Active carborn>Amberite IR-120 6. The powder type of the soy protein source obtained by concentration below $60^{\circ}C$ contains 12.51% of moisture, 66.31% of protein, 4.25% of fat, 12.75% of carbohydrate, 4.18% of ash.

• Journal of the Korean GEO-environmental Society
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• 제15권3호
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• pp.33-40
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• 2014

In this paper, mechanical and germination characteristics of stabilized dredged soils were investigated to recycle dredged soil in eco-friendly manner such as waterfront construction. Non sintering binder (NSB), which was developed by using interchemical reactions between slag, high-calcium fly ash, alkali activator on the dredged marine clay, was added to dredged soil. Ordinary portland cement was also used for the comparison of two binders. Experimental tests such as flow test and unconfined compressive test were carried out to evaluate characteristics of stabilized dredged soil. Leaching test, pH measure, vegetation germination test were also conducted to consider environmental applicability. The unconfined compressive tests shows that unconfined compressive strength (UCS) also increases with the increase of curing time and mixed ratio. UCS of NSB mixtures were higher than those of OPC mixtures. Germination tests showed that germination and sprouting date are better in NSB mixture than OPC mixture. It can be explained that germination decreased as pH and 7-day strength increased.

• Journal of Korean Society of Environmental Engineers
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• 제34권7호
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• pp.488-494
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• 2012

This study was conducted to determine the optimal ratio of sludges from milk processing industry (MPS), paper-mill industry (PMS) and night-soil treatment plant (NSS) for vermicomposting. Five different ratios, 0 : 80 : 20 (MPS-0), 25 : 60 : 15 (MPS-25), 50 : 40 : 10 (MPS-50), 75 : 20 : 5 (MPS-75), and 100 : 0 : 0 (MPS-100 : control) MPS : PMS : NSS by wet weight were tested in a small plot experiment. The experiment for each mixing ratio was performed for 2 weeks with the three replications. MPS-100 (100 : 0 : 0) only had the highest decomposition rate with 19.9%, followed by MPS-25, MPS-50, MPS-75 and MPS-0 with 19.5, 19.1, 17.6 and 16.7%, respectively. Except for MPS-100, Vermicomposting resulted in increase in ash, T-P, $NO_2{^-}-N$, $NO_3{^-}-N$, Mg, K, As, Cd and Cu, whereas moisture, VS (Volatile Substance), TKN (Total Kjeldahl Nitrogen), $NH_4{^+}-N$, Ca, Hg and Pb were lower in the final cast than the initial feed mixture. Meanwhile Zn showed very slight difference and Cr and Ni did not show any tendency between the feed mixture and the final cast. In the case of MPS-100, where the decomposition rate was the highest, all the heavy metals in the final cast except for Hg were increased. All the vermicomposts produced from five different mixing ratios of the vermicomposting sludges met the Korea Standard as by-product compost.

• Journal of the Korean Society of Food Science and Nutrition
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• 제17권3호
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• pp.242-248
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• 1988

Plasteins were synthesized from a peptic sardine protein hydrolysate by pepsin, ${\alpha}-chymotrypsin$ pretense(from Aspergillus saitoi) and papain under the optimum conditions of previous paper. L -glutamic acid diethylester and L-leucine ethylester also were incorporated into plastein during the plastein reaction by papain. General composition, yield, molecular weight and amino acid composition were measured. The protein, ash and lipid rontent of plasteins were $81.1{\sim}88.2%$, $1.9{\sim}7.6%$ and $0.3{\sim}0.8%$, respectively. The yield of plasteins were pretense plastein 52.3%, papain plastein 44.2%, pepsin plnstein 43.6%, ${\alpha}-chymotrypsin$ plastein 43.2%. Leu -papain plastein 33. 2% and Glu - papain plastein 29.0%. The glutamic acid and leucine content in Glu -papain plastein and Leu -papain plastein were 39.0%, 37.5%, respectively. While the contents in the papain plastein were 14.3%, 7.1%, respectively. The amino acid composition of plasteins were similar to that of peptic sardine protein hydrolysate. The major molecular weight of the peptic hydrolysnte estimated by gelfilteration were 1,800 and 285, and those of plasteins were 26,000 and 9,100 for ${\alpha}-chymotrypsin$, 23,000, 10,000 and 4,300 for pepsin, 18,000 for pretense, 13,000 for papain, 29,000 for Leu -papain plastein and 19,000 for Glu -papain plastein.

• Journal of the Korean Recycled Construction Resources Institute
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• 제7권3호
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• pp.49-55
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• 2012

In this paper, the physical properties of lightweight aggregate such as density and water absorption according to addition ratio and type of flux were investigated. When using $Na_2CO_3$ as flux of lightweight aggregate, burnability was available at low burning temperature and water absorption increased. And as increasing addition ratio of $CaCO_3$, NaOH, $Fe_2O_3$, absorption decreased and $CaCO_3$, NaOH, $Fe_2O_3$ were considered improper to use flux of lightweight aggregate because of high dried density. $Na_2SO_4$ was proper to use flux of lightweight aggregate due to dried density $1.35{\sim}1.50g/cm^3$ and lower absorption. When using glass abrasive sludge as flux of lightweight aggregate, dried density and water absorption were in the range of $1.45{\sim}1.55g/cm^3$ and 9~12% respectively. It was indicated that as increasing addition ratio of blast furnace slag powder, density increased whereas absorption decreased. In use of oxidizing slag as flux, artificial lightweight aggregate which have dried density $1.46g/cm^3$, water absorption 8,5 % can be manufactured at 10 % of addition ratio.

• Journal of the Korean Society of Food Science and Nutrition
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• 제16권3호
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• pp.27-34
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• 1987

The present paper was attempted to obtain the basic date concerning a reasonable preparing method and optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard quality of Kochujang, the chemical compositions and the volatile components of Kochujang was discussed. The native Kochujang collected from 80 households contained 40.51% of moisture, 6.00% of salts, 3.25 % of crude fat, 10.30 % of crude ash, pH 4.79, 9.28ml of tillable acidity. 19.60% of reducing sugar, 179.51 mg/100g of amino nitrogen and 4.43% of total nitrogen. The volatiles of Kochujang were extracted by a steam-distillation under the reduced pressure and determined by gas chromatography-mass spectrometry (GC-MS). Total volatile components identified in the native Kochujang were 46 components, i. e., 30 components in neutral fraction, 8 components in phenolic fraction and 8 components in acidic fraction, respectively. But no components were detected basic fraction.

• Journal of Environmental Science International
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• 제11권10호
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• pp.1109-1116
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• 2002

This study analyzed concentrations of volatile organic compounds (VOCs) produced from incineration of papers at $600^{\circ}C$. The papers used in this study included A4 papers (new, printed with ink-jet, printed with carbon), newspapers (printed with bean oil, printed with a general newspaper ink), packaging box, document envelope, single-use paper cup, and cosmetic tissue. Papers were heated from room temperature upto $600^{\circ}C$ providing air inside of the electric furnace and then they were oxidized for 80 minutes at $600^{\circ}C$ maintaining the same air supply. VOCs emitted from the incineration process were sampled using an air sampling pump and bags for 160 minutes and then the components and concentrations of the VOCs were analyzed by a CC-MS. The most prominent chemical structure of the Vous identified from incineration of the papers was furans and then furans were followed by aromatics and aliphatic alkenes. About 40% of the identified VOCs contained double bonds, which have relatively a high ozone (ground level) formation potential, within their molecular structure. Also, some cancer suspecting compounds like benzene, dichlorormethane and chloroform were identified.

• Journal of the Korean Society of Food Science and Nutrition
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• 제21권2호
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• pp.201-206
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• 1992

Pinus pollen is used as the chief ingredient for Song-wha-dashik (Korea's traditional pattern-pressed candy). It has been the food stuff indispensable especially on the occasion of performing ancestral rites and holding a banquet since Shilla and Koryo Dynasty. In this paper, therefore, a new examination is made of the nutritive ingredients of the very Pinus pollen. Analysis has been made of the proximate composition, minerals, heavy metals, vitamins and free sugars of the Pollen of both Pinus densinora Siebol et Zuccarini and Pinus rigida Miller. In the proximate composition, Pinus rigida Miller is high except in free sugar ; crude ash (4.0%), crude protein (15.0%), crude fat (2.5%), crude fiber (17.5%). A lot of minerals have been found in both the samples. They contain Mg, Cl, Ca, Fe, Mn, Na, Zn, etc. In heavy metals, both the samples contain the same quantity of Cd(0.3 ppm) and the contents of Pb, Cu, and As are lower than the maximal limit permitted for food stuff. The contents of vitamin B$_1$, B$_2$, vitamin C are a little higher in Pinus rigida Miller : in vitamin E, on the contrary, Pinus densiflora Siebol et Zucarini (1.6 mg) doubles Pinus rigida Miller (0.8 mg). In free sugars, the results is as follows : 6.6%/6.9% in sucrose : 0.2% in fructose : 2.1% /2.9% in glucose respectively.

• Journal of Environmental Health Sciences
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• 제19권4호
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• pp.51-58
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• 1993

The integrated solid waste management for Seoul Metropolitan city can be established on the basis of the following hierarchy of priorities: 1. Efforts for source reduction should be propelled by both government and citizens to achieve the effects of resource conservation. The adequate production and consumption which are environmentally amenable and sustainable can be induced by the reasonable imposition of deposit money for waste treatment to one-time use products. To accomplish source reduction effectively, the induction of legal and institutional regulation of producer and consumer participation is requisite. 2. For resource recovery, wastes generated should be recycled as far as practicable. Community residents are responsible to separate discharge, the authorities concerned have responsibility of separate collection, and recycling industry should be assissted through tax reduction and financing. Resource separation facilities can be constructed at Kimpo Metropolitan landfill site for wastes not separately collected due to some unavoidable circumstances. 3. Garbage should be composted. Garbage is uneconomical for incineration, because it has high moisture content and low calorie, thus there is no reason for the incineration of garbage even though garbage is classified into combustibles. Composting facilities can be located at sites which are not densely populated and easily accessible to transportation, for example, Kimpo Metropolitan landfill site. Compost produced can be managed by the authorities for the use of fertilizer to a green tract of suburban land and farms. 4. Nonhazardous combustible wastes not recyclable can be utilized for thermal recovery at the incinerators which are completely equipped with pollution control devices. According to the trend of local autonomy and the equity principle of local autonomous entities, incineration facilities of minimal capacity required can be constructed at each districts of Seoul Metropolitan city which have organized local assembly. In case of Yangcheon district, the economically combustible waste quantity is about 260 tons/day which exceeds 150 tons/day, the incineration capacity of existing facility. But, from now on, waste quantity can be reduced substantially by the intensive efforts of citizens for source reduction and recycling and the institutional support of administrative organizations. Especially, it is indispensable for the government to constitute institutional and technological bases that can recycle paper and plastics form 43% of waste generated. A good time for constructing of incineration facilities for municipal solid waste can be postponed to the time that pollution control technologies of domestic enterprises are fully developed to satisfy the standards of air pollution prevention, because the life expectancy of Kimpo Metropolitan landfill site is about 25 years. Within this period, institutional improvements and technological advancements can be attained, while the air qual. ity of Seoul Metropolitan city can be ameliorated to the level to afford incineration facilities. 5. For final disposal, incombustibles and ash are landfilled sanitarily at Kimpo Metropolitan landfill site.