• 한국분말재료학회지
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• 제21권2호
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• pp.119-123
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• 2014

Pt has been widely used as catalyst for fuel cell and exhausted gas clean systems due to its high catalytic activity. Recently, there have been researches on fabricating composite materials of Pt as a method of reducing the amount of Pt due to its high price. One of the approaches for saving Pt used as catalyst is a core shell structure consisting of Pt layer on the core of the non-noble metal. In this study, the synthesis of Pt shell was conducted on the surface of $TiO_2$ particle, a non-noble material, by applying ultraviolet (UV) irradiation. Anatase $TiO_2$ particles with the average size of 20~30 nm were immersed in the ethanol dissolved with Pt precursor of $H_2PtCl_6{\cdot}6H_2O$ and exposed to UV irradiation with the wavelength of 365 nm. It was confirmed that Pt nano-particles were formed on the surface of $TiO_2$ particles by photochemical reduction of Pt ion from the solution. The morphology of the synthesized Pt@$TiO_2$ nano-composite was examined by TEM (Transmission Electron Microscopy).

• 한국분말재료학회지
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• 제18권6호
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• pp.532-537
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• 2011

Thermally stable $TiO_2$/Pt/$SiO_2$ core-shell nanocatalyst has been synthesized by chemical processes. Citrated capped Pt nanoparticles were deposited on amine functionalized silica produced by Stober process. Ultrathin layer of titania was coated on Pt/$SiO_2$ for preventing sintering of the metal nanoparticles at high temperatures. Thermal stability of the metal-oxide hybrid catalyst was demonstrated heating the sample up to $600^{\circ}C$ in air and by investigating the morphology and integrity of the structure by transmission electron spectroscopy. The surface analysis of the constituent elements was performed by X-ray photoemission spectroscopy. The catalytic activity of the hybrid catalysts was investigated by CO oxidation reaction with oxygen as a model reaction.

• 한국수산과학회지
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• 제48권5호
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• pp.596-603
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• 2015

This study investigated the effects of adding oyster shell powder (OSP) from Crassostrea gigas on the food quality of Chinese cabbage Kimchi (CCK). We monitored the changes in microbial levels, pH, acidity and sensory evaluation during the fermentation of CCK treated with various contents of OSP. The microbial assay showed that adding OSP to CCK inhibited the growth of viable cells, total coliforms, and lactic acid bacteria, with the greatest growth inhibition against lactic acid bacteria over the fermentation period. After fermentation for 18 days, the lactic acid bacterial counts in CCK treated with OSP (0.3%, 0.5% and 1%) were at least 1 log CFU/g lower than those of control CCK. In addition, the pH and acidity of CCK treated with OSP were lower than in control CCK over the fermentation period. The overall sensory evaluation of CCK with 0.3% OSP was better than that of control CCK after fermentation for 24 days. In conclusion, OSP treatment, especially 0.3% OSP, enhances the food quality and extends the self-life of CCK, while minimizing the detrimental effects on its sensory characteristics.

• 한국환경과학회지
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• 제27권9호
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• pp.763-770
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• 2018

Bioremediation in situ is heavily dependent on the oxygenic environment which would privide the dwelling microorganism with sufficient oxygen. The situation could be easily resolved with supply of an Oxygen Releasing Compound (ORC). In this paper we prepared that sort of material out of oyster shell powder (mostly calcium carbonate) that prevails every shore areas of the country. We used two different oxidizing methods in the first step of the whole manufacturing process-conventional heating in a furnace and an ultrasound generator to obtain calcium oxide. Then that calcium oxide was further oxidized into calcium peroxide which may release oxygen under a moisturized condition. The oxygen releasing experiments were run to test the performance of our products, and to determine the gas kinetics during the experiments. Interestingly, calcium peroxide derived from ultrasound treatment was much more energy-effective as ORC than that from furnace heating although the heat derived process was better than that of ultrasound in terms of oxygen content and its releasing rate. We also found that most of the data collected from the gas releasing experiments fairly supported an ordinary $1^{st}$ order kinetics to oxygen concentration, which shaped a sharp discharge of oxygen at the very early moment of each test.

• 한국식품영양학회지
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• 제16권2호
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• pp.130-137
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• 2003

The squid had not been utilized for gel products because of its lower gel forming ability. The objectives of this study were as followed; 1) the optimum heating condition on squid meat paste products and 2) the optimum added level for jelly strength of squid meat paste products. Optimum heating conditions of squid meat kamaboko were as followed; setting(pre-heating) at 15$^{\circ}C$ or 55$^{\circ}C$ for 2 hours and heating at 9$0^{\circ}C$ for 60 minutes. The additives examined were as follows; 20mM EDTA, 10mM PMSF, 5 $\mu$mol/100g TGase, 0.2% potassium bromate, 2% collagen, 2% sucrose ester of stearic acid and 1% egg shell powder. The effects of additives on jelly strength were observed as follow, in descending order; 10mM of PMSF>5 $\mu$mo1/100g of TGase>0.2% of potassium bromate>20mM of EDTA. But sucrose ester of stearic acid and 1% egg shell powder were no effect. The solvents examined were as follows; n-amyl alcohol, n-butyl alcohol, n-hexyl alcohol, ethyl alcohol, ethylene glycol, propylene glycol and glycerin glycol. It showed that high jelly strength as 787gㆍcm for 3% of n-butyl alcohol and 749gㆍcm for 3% of n-amyl alcohol. To adding 5% of n-butyl alcohol and n-amyl alcohol, gave the highest jelly strength and water holding capacity(WHC). Effect of alcohol on jelly strength appeared higher value at added 5% of n-butyl alcohol than n-amyl alcohol, and flying squid product was higher than jumbo squid product.

• 한국축산식품학회지
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• 제34권3호
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• pp.372-377
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• 2014

This study was conducted to evaluate the effects of oyster shell calcium powder (OSCP) as a substitute for phosphates in curing agent, on the quality of restructured pork ham. Restructured pork ham was processed under six treatment conditions: T1 (no additives), T2 (0.3% sodium tripolyphosphate), T3 (1.5% NaCl+0.5% whey protein), T4 (1.5% NaCl+0.5% whey protein+0.15% OSCP), T5 (1.5% NaCl+0.5% whey protein+0.3% OSCP), and T6 (1.5% NaCl+0.5% whey protein+0.5% OSCP). Addition of OSCP significantly increased the ash content and pH of restructured pork ham (p<0.05), but did not affect the cooking loss and water holding capacity values of restructured pork ham. Addition of OSCP had no effect on Hunter a and b surface color values of restructured pork ham, but did decrease the Hunter L surface color value (p<0.05). The addition of 0.5% OSCP showed significantly higher chewiness and springiness values of restructured pork ham, compared with the addition of phosphates (p<0.05). In conclusion, the addition of OSCP combined with low NaCl and 0.5% whey protein can be considered a viable substitute for phosphates in the curing agent, when processing restructured pork ham.

• 한국수산과학회지
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• 제36권6호
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• pp.716-722
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• 2003

This study determined the optimum dosage for coagulation reactions of red tide organisms (RTO) using a combination of ignited oyster shell powder (10sp) and loess and examined the electrokinetic and rheological characteristics of their flocs. Two kinds of RTO, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan Bay and cultured in the laboratory. Coagulation experiments were conducted using various concentrations of IOSP, loess, IOSP+1oess, RTO, and a jar tester RTO cell numbers were counted for both the supernatant and RTO culture solution. The removal rates increased rapidly with increasing IOSP concentrations up to 50 mg/L and loess concentrations up to 800 mg/L. A removal rate of $100\%$ was reached at 400 mg/L of IOSP and 6,400 mg/L of loess. The highest increment $(16.7\%)$ of the rates of coagulation reaction occurred using both IOSP and loess (50+200 mg/L) in comparison with IOSP alone. The rate of coagulation reaction using both IOSP and loess (50+200 mg/L), $90.6\%,$ was similar to employing either IOSP of 150 mg/L or loess of 3,200 mg/L. All of the coagulation liquids for RTO, IOSP (200 mg/L), loess (200 ma/L), and IOSP+1oess (200+200 mg/L) revealed non-Newtonian fluid properties and therefore their shear rate vs. shear stress curves were non-linear. The coagulation liquids revealed elastic body properties at a lower shear rate increasing in the following order: RTO, IOSP (200 mg/L), loess (200 mg/L), and IOSP+1oess (200+200 mg/L. IOSP+1oess (200+200 mg/L) especially demonstrated plastic flow properties at a lower shear rate.

• 한국토양비료학회지
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• 제49권5호
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• pp.456-460
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• 2016

Biofertilizers are increasingly available in the market as one of the alternatives to chemical fertilizers. The supply of a high number of viable microorganisms is important for farmers. Lysobacter capsici YS1215 producing chitinases and gelatinases, isolated from soil in Korea, was evaluated for the establishment of an optimal medium condition of its shelf life under an in vitro condition. In this study, the population density of a biofertilizer (L. capsici YS1215) in media containing crab shell and gelatin powder (M1, M2, M3 and M4) was observed to be higher than that of populations grown in TSB (Tryptic soy broth) media (M5, M6 and M7) during experimental period. In addition, the population density at 11 months was over $10^6\;CFU\;mL^{-1}$ in M1, M3 and M4, but under $10^6\;CFU\;mL^{-1}$ in M2, M5, M6 and M7. The best optimal medium for the shelf life was M1 ($2.6{\times}10^6\;CFU\;mL^{-1}$) containing both chitinous and gelatinous materials at 11 months. Therefore, this study provided results of the appropriate medium composition for the enhancement of the shelf life of L. capsici YS1215.

• 한국토양비료학회지
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• 제47권4호
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• pp.299-305
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• 2014

In this paper, fractional factorial screening design (FFSD) and central composition design (CCD) were used to optimize the medium components for producing chitinase and gelatinase by Lysobacter capsici YS1215. Crab shell powder, nutrient broth and gelatin were proved to have significant effects on chitinase and gelatinase activity by FFSD first. An optimal medium was obtained by using a three factor CCD, which consisted of nutrient broth of $2.0gL^{-1}$, crab shell powder of $2.0gL^{-1}$ and gelatin of $1.0gL^{-1}$, respectively with the highest chitinase activity ($3.34UmL^{-1}$) and gelatinase activity ($14.15UmL^{-1}$). This value was 3.76 and 1.11 fold of the chitinase and gelatinase activity, respectively, compared to the lowest productive medium in the design matrix. In investigating potential of these enzymes partially purified from L. capsici YS1215 for biotechnological use, the crude enzymes was found to be inhibition against pathogenic fungal mycelia: Colletotrichum gleosporioides, Phytophthora capsici, and Rhizoctonia solani. In this study, we demonstrated the optimal medium for producing the chitinolytic and gelatinolytic enzymes by the strain YS1215 and the role of their enzymes that may be useful for further development of a biotechnological use and agricultural use for biological control of phytopathogenic fungi.

• Asian-Australasian Journal of Animal Sciences
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• 제32권1호
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• pp.118-125
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• 2019

Objective: This study investigated the effects of soapnut (Sapindus mukorossi) shell powder (SSP) on serum hormone level, egg quality, semen characteristics and reproductive performance of broiler breeders fed with a maize-soybean meal based diet. Methods: Ninety six female and twenty four male CARIBRO-VISHAL broiler breeders, 38-week old, were individually caged and randomly allocated to four treatment groups (24 female breeders/treatment and 6 male breeders/treatment): an un-supplemented control (T1) and three groups with 0.0176% SSP (group T2), 0.026% SSP (group T3) and 0.0528% SSP (group T4), to have supplementary saponin at 0, 50, 75, and 150 ppm, respectively, for 42 days. Results: The results indicated that serum (p<0.001) and seminal plasma (p<0.05) testosterone level, semen volume (p<0.001), mass motility (p<0.001), and live spermatozoa count (p<0.001) was increased in groups T3 and T4 compared to T2 and control groups. Compared with control group, total sperm count was increased (p<0.001) and dead spermatozoa count was decreased (p<0.001) in SSP supplemented groups. Supplementation of SSP did not affected the quality of egg lay. Compared with control group, fertility (p<0.01) and hatchability (total eggs set and fertile eggs set) (p<0.001) were significantly improved in SSP supplemented groups with the highest improvement in T3 treatment group. Embryonic death was decreased (p<0.001) in SSP supplemented groups compared to control; lowest embryonic death was recorded in T3 treatment group. Conclusion: Thus, it was concluded that dietary supplementation of 0.026% SSP (saponin equivalent 75 ppm) improved the reproductive performance of broiler breeders.