• Korean Journal of Poultry Science
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• v.31 no.3
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• pp.193-198
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• 2004

This study was conducted for improvement of meat quality in broiler chcikens. Birds were fed basal diet(control), ferritin, illite, betafin, or wood vinegar counting broiler feed according as broiler growth stage. Birds fed with basal diet, which was distributed under the best environmental condition, were more weight gain than other groups reared under same environmental condition. In the mean weight gain, the ferritin-group showed the highest and the illite-group showed the lowest among the feed additive groups; therefore, the effect of feed requirement change in odor reduction in illite and methyl saving of betafin was lower than those of other feed additives along to pass rear time. Meat quality was appraised by National Livestock Research Institute of RDA. Except the control-group, that had the best feed conversion ratio, the cooking loss of the illite-group was the biggest among groups although the illite-group chickens had a good water hold capacity. Therefore, illite is not good for making merchandise by reason that group chickens get reduction carcass weight after slaughter. On the other hand, the ferritin-group got the highest point of shear stress, cooking loss, and crude fat level. That group showed the best appraise in both breast and leg of sensory test in company and also feed conversion ratio was the highest among feed additive groups. As a result, the ferritin-group might use for making new merchandise among the feed additive groups.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.12
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• pp.1854-1863
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• 2019

Objective: To effectively use corn stover resources as animal feed, we explored the chemical composition and in vitro digestibility of corn stover during field exposure and the fermentation characteristics of silage prepared with lactic acid bacteria (LAB) and cellulase. Methods: Corn ears including the cobs and shucks were harvested at the ripe stage. The corn stover was exposed in the field under natural weather conditions. Silages were prepared after 0, 2, 4, 7, 15, 30, and 60 d of exposure. Corn stover was chopped into approximately 1 to 2 cm lengths and then packed into 5 liter plastic silos. The ensiling density was $550.1{\pm}20.0g/L$ of fresh matter, and the silos were kept at room temperature ($10^{\circ}C$ to $25^{\circ}C$). Silage treatments were designed as follows: without additives (control), with LAB, with cellulase, and with LAB+ cellulase. After 45 d of fermentation, the silos were opened for chemical composition, fermentation quality and in vitro digestion analyses. Results: After harvest, corn stover contained 78.19% moisture, 9.01% crude protein (CP) and 64.54% neutral detergent fiber (NDF) on a dry matter (DM) basis. During field exposure, the DM, NDF, and acid detergent fiber (ADF) contents of corn stover increased, whereas the CP and water-soluble carbohydrate contents and in vitro digestibility of the DM and CP decreased (p<0.05). Compared to the control silage, cellulase-treated silage had lower (p<0.05) NDF and ADF contents. The pH values were lower in silage treated with LAB, cellulase, or LAB+cellulase, and lactic acid contents were higher (p<0.05) than those of the control. Silage treated with cellulase or LAB+cellulase improved (p<0.05) the in vitro DM digestibility (IVDMD) compared to that of the control or LAB-treated silage. Conclusion: Corn stover silage should be prepared using fresh materials since stover nutrients are lost during field exposure, and LAB and cellulase can improve silage fermentation and IVDMD.

• Korean Journal of Organic Agriculture
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• v.29 no.2
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• pp.241-256
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• 2021

The current study was to evaluate the antioxidant activity of Phyllostachys bambusoides (PHB) as a feed additives and investigate whether its antioxidant activity could be helpful for increasing rumen fermentation characteristics and methane reduction. The antioxidant activity results showed that total polyphenols and flavonoids contents were 43.54 ± 8.68 mg CE/g and 17.13 ± 0.45 mg QE/g, respectively, and the IC₅₀ values for 1,1-diphenyl-2-prcrylhydrazyl (DPPH) and 2,2'-azino-bis (3- ethylbenzthiazoline-6- sulphonic acid) (ABTS) radical scavenging activity were 163.13 ± 19.25 ㎍/mL and 97.07 ± 4.46 ㎍/mL, respectively. Two heads of cannulated Hanwoo (450 ± 30 kg), consuming timothy hay and a commercial concentrate (60:40, w/w) twice daily (at 09:00 and 17:30) at 2% of body weight, with free access to water and a mineral block, were used as rumen fluid donors. An in vitro incubation experiment was performed after 6, 12, 24, 48, and 72 hr with PHB added at concentration of 2, 4, and 6% of timothy hay basis. Total gas emission decreased as the amount of PHB addition increased at 6 and 24 hr of incubation. However, PHB addition did not affect total volatile fatty acid production, and methane and carbon dioxide emission also decreased as the amount of addition increased at 48 hr of incubation. Therefore, PHB was expected to be used as methane reducing additives in the ruminants.

• Membrane Journal
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• v.34 no.3
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• pp.192-203
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• 2024

The advancement of commercially viable gas separation membranes plays a pivotal role in improving CO₂ separation efficiency. High-molecular-weight poly(ethylene oxide) (high-Mw PEO) emerges as a promising option due to its high CO₂ solubility, affordability, and robust mechanical attributes. However, the crystalline nature of high-Mw PEO hinders its application in gas separation membranes. This study proposes a straightforward blending approach by incorporating various polymeric additives into high-Mw PEO to address this challenge. Four commercially available, water-soluble polymers, i.e. poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), poly(acrylic acid) (PAA), and poly(vinyl pyrrolidone) (PVP) are examined as additives to enhance membrane performance by improving miscibility and reducing PEO crystallinity. Contrary to expectations, PEG and PPG fail to inhibit the crystalline structure of PEO and result in membrane flaws. Conversely, PAA and PVP demonstrate greater success in altering the crystal structure of PEO, yielding defect-free membranes. A thorough investigation delves into the correlation between changes in the crystalline structure of high-Mw PEO blend membranes and their gas separation performance. Drawing from our findings and previously documented outcomes, we offer insights into designing and selecting additive polymers for high-Mw PEO, aiming at the creation of cost-effective, commercially viable CO₂ separation membranes.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.4
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• pp.281-288
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• 2011

Recently, researches that a variety of contaminants in water are removed by sonolysis technology with oxidation and pyrolysis process from cavitation were conducted. However, there are few studies for sonochemical treatment by a pilot-scale ultrasound system. This research focused on developing pilot-scale ultrasound systems, which could be an continuously effective treatment for a large volumes of contaminants, and demonstrating the feasibility of utilizing these systems to remove naphthalene from groundwater. V-120 type reactor was found to be 1.4~2.2 times higher effective than the normal type. A total of three different pilot scale's systems consisted of installing effluent and irrigation water in order to be a continuos system, including supplemental additives, and applying a V-120 type reactor and a external cooling cycle system. Naphthalene levels treated by three systems were lower than a recommended guideline of naphthalene for drinking water in EPA. Especially, the naphthalene removal efficiencies of PS1 and PS2 systems were over 97%. The pilot-scale continuous ultrasound clean-up system delivered over 84~95% naphthalene removal efficiency for treatment of 10~20 liter of groundwater. In addition, the ultrasound system could be successfully applied to the conditions of artificial and genuine groundwater contaminated with naphthalene.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.1
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• pp.48-53
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• 2009

The effect of bloating and fluxing agent on the microstructure and physical properties were studied in manufacturing the artificial lightweight aggregates of bulk density below] using clay and stone sludge. In case of the aggregates added only with bloating agent, the bulk density and water absorption were $0.5{\sim}1.0$ and $41{\sim}110%$ respectively but the microstucture was not uniform with a rough appearance. For the aggregates added with a fluxing agent and one bloating agent, a part of shell was lost due to explosion of specimen caused by over-bloating during a sintering. The mixed addition of bloating agents with vacuum oil, carbon and ${Fe_2}{O_3}$ made the microstructure homogeneous by generating an uniform black core and shell structure. The aggregates added with mixed agents and sintered at $1200^{\circ}C$ showed the bulk density 67 % lower and water absorption 48 times higher than those of the specimen with no additives. ]n this study, the artificial lightweight aggregates showing the bulk density of $0.5{\sim}1.0$ and water absorption of $50{\sim}125%$ could be fabricated to apply to various fields.

• Advances in environmental research
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• v.6 no.3
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• pp.159-171
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• 2017

A successful oil well drilling depends largely on a good mud Program. During drilling, mud provides sufficient hydrostatic pressure, removes drill cuttings and cools drill bits. Mud additives are always required to provide sufficient hydrostatic pressure to ensure borehole stability. Barium Sulphate ($BaSO_4$) also known as barite is the prevalent weighting material but there is needed to develop local materials to augment the use of Barite. The present search is concerned on the early Carboniferous succession exposed in Um Bogma Formation, west central Sinai, Egypt as a new weighting agent in drilling fluids. The increases in the cost of drilling fluids and a shortage of using barite have introduced the locale dolomite as alternative weighting materials. The rheological properties of mud drilling samples weighted by local dolomite samples are being examined and investigated to know its potential to be used as a weighting material in drilling mud. Two mud samples were prepared which comprised of fresh water, caustic soda, bentonite and the weighting material. The weighting materials are added to achieve the required density. The first sample: Water-based mud with commercial barite of density between 10.00 lb/gm and 18.00 lb/gm. The second sample: Water-based mud with dolomite of density between 10.00 lb/gm and 18.00 lb/gm. These samples were analyzed and the density, rheological properties, aging of barite and dolomite and solid contents were investigated. At 10.00 lb/gm, the yield point of dolomite was $20.00lb/100ft^2$ and barite $22.00lb/100ft^2$ while the 10 second gel strength of dolomite was $30.00lb/100ft^2$ and $22.00lb/100ft^2$ for barite. Similarly, little difference was observed in plastic and apparent viscosities. At 10.00 lb/gm, the plastic and apparent viscosities of dolomite were 8.00 cp and 20.00 cp while barite was 8.00 cp and 24.00 cp. The result show that dolomite mud sample gave a little higher yield point and gel strength than barite mud sample. Therefore, dolomite has the potential to be used as weighting material in drilling mud in place of barite thereby enhancing the local content initiative of the government. When dolomite is sourced locally and used it will reduce overall mud and drilling costs.

• Applied Biological Chemistry
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• v.12
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• pp.19-24
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• 1969

As a one of the new methods for soybean protein food processings, an attempt was made to decompose steamed soybean protein to amino acids, peptides, and other water soluble forms by the use of protease produced by Aspergillus sojae, and extract them to use as additives of low protein foods or weaning-foods of children. In this paper, as a one part of this subject, the optimum condition, such as optimum pH, temperature, digestion period, raw material's mixing ratio with wheat meal, amount of water added, and effect of sodium chloride addition, to decompose and extract soybean protein were studied. They were obtained when mixing raw materials with wheat meal in the ratio of 10:4 and adding six folds of water at $40-45^{\circ}C$, pH 5-8 for 18 hrs. digestion. Although sodium chloride addition exerted an unfavorable influence upon the decomposition of the aforementioned materials, it was effective to prolongation of digestion period. Under the abovementioned optimum conditions, the maximum extractability of soybean protein as forms of amino acids, peptides, and other water soluble forms, was nearly 70 percent against protein content of raw materials.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.213-219
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• 2002

The CellCaSi, a porous silicate material, was tested for the removal of phosphorus (P as phosphate) in water. The effect of the CellCaSi was investigated on the basis of both particle size (under 1,2, and 4 mm) and added amount (0, 1, 2.5, 5, and 10 g/1) of the CellCaSi. The removal efficiency of phosphorus was highest with a particle size of under 1 mm and also increased with an increasing amount of the CellCaSi. The pH change showed little effect on the phosphorus removal of the CellCaSi. The calcium ion was eluted from the CellCaSi into the water, while the aluminium and iron were not. The eluted calcium ion was combined with dissolved phosphorus and then precipitated. The highest removal efficiency of phosphorus was obtained by the combined addition of the CellCaSi, calcium chloride, and ferric chloride. That is, the phosphorus concentrations of 0.10 and 1.0 mg/1 decreased to 0.03 and 0.47 mg/l by the addition of the CellCaSi (1 g/l), calcium ion (30 mg/l), and ferric ion (1 mg/l) at day 8 after treatment. The water qualities at the end of the experiment were as follows: pH was 8.1 and conductivity was 318 ${\mu}$S/cm (a registered maximum conductivity of 500${\mu}$S/cm for raw and potable wafers).

• Membrane Journal
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• v.31 no.6
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• pp.443-455
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• 2021

In this study, polyphenylene sulfide (PPS) was used as a support and a separator was manufactured using polysulfone and inorganic additives to manufacture a separator with low membrane resistance for application of an alkali water electrolysis system, and then the effect on the thickness and porosity of the support was analyzed. The PPS felt used as a support was compressed with variables of temperature (100℃, 150℃, 200℃) and pressure (1 ton, 2 tons, 3 tons, 5 tons) to adjust the thickness. A porous separator could be manufactured by preparing a slurry with polysulfone using BaTiO₃ and ZrO₂ which have high hydrophilicity and excellent alkali resistance as inorganic particles and casting the slurry on a compressed PPS felt. Changes in morphology of the separator according to compression conditions were confirmed through an electron scanning microscope (SEM). After that, the porosity was calculated, and the thickness and porosity tended to decrease as the compression conditions increased. Various characteristics were evaluated to confirm whether it could be used as a separator for water electrolysis. As a result of measuring the mechanical strength, it was confirmed that the tensile strength gradually increased as the compression conditions (temperature and pressure) increased. Finally, it was confirmed that the porous separator manufactured through the alkali resistance test has excellent alkali resistance, and through the IV test, it was confirmed that the membranes compressed at 100℃ and 150℃ had a lower voltage and improved performance than the existing uncompressed membrane.