• Journal of the Korean Ceramic Society
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• v.39 no.6
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• pp.523-527
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• 2002

LiMn$_2$O$_4$ compounds were synthesized by calcining a mixture of LiOH and MnO$_2$(CMD) at 47$0^{\circ}C$ for 10 h and then calcining again at $650^{\circ}C$ to 90$0^{\circ}C$ fur 48 h in air with intermediate grinding. All the synthesized samples exhibited XRD patterns for the cubic spinel phase with a space group Fd3m. The lattice parameter increased gradually as the sintering temperature rose. The electrochemical cells were charged and discharged fur 20 cycles at a current density 300$\mu$A/$\textrm{cm}^2$ between 3.5 V and 4.3 V. The voltage vs. discharge capacity curves for all the samples showed two plateaus. The LiMn$_2$O$_4$ sample calcined at 90$0^{\circ}C$ had the largest first discharge capacity. This sample exhibited the best crystallinity, had relatively large lattice parameter and had relatively large particles with rectatively homogeneous size. All the samples showed good cycling performances. Among all the samples, the LiMn$_2$O$_4$ calcined at 85$0^{\circ}C$ had relatively large first discharge capacity and very good cycling performance. The addition of excess LiOH and the mixing in ethanol considered to help the formation of the more LiMn$_2$O$_4$ phase per unit weight sample and the more stable LiMn$_2$O$_4$phase. These led to the larger discharge capacities and the better cycling performances. The cyclic voltammograms fur the second cycle of the LiMn$_2$O$_4$ samples showed the oxidation and reduction peaks around 4.05 V and 4.18 V and around 4.08 V and 3.94 V, respectively. The larger first discharge capacity of the sample calcined at the higher temperature is related to the larger lattice parameter.

• Korean Journal of Construction Engineering and Management
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• v.6 no.4 s.26
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• pp.142-151
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• 2005

Several advanced countries have been continually developed PHC pile cutting automation machines for improving productivity, safety and quality of the conventional PHC pile cutting work. However, the target work of the previously developed PHC pile cutting automation machines is only crushing the head of PHC pile. Dangerous grinding work is still performed by workers with seven inch hand grinder. In domestic construction industry, the PHC pile cutting work is usually performed by a crusher and three to four skilled workers. Recent analysis results of the PHC pile cutting work reveal that it frequently makes a lot of cracks which significantly reduce the strength of the pile and is labor-intensive work. The primary objective of this study is to propose the end-effector which can effectively break PHC pile without any longitudinal cracks and to develop an automated pile cutting machine having unified grinder and crusher parts through a wide variety of laboratory and field tests. It is anticipated that the development of the automated pile cutting machine would be able to bring improvements in safety, productivity, quality as well as cost saving.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.804-810
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• 2003

The fine powder produced by heating and grinding of the waste concrete in the waste construction was investigated whether utilize as substitution raw material of SiO$_2$, CaO, and Al$_2$O$_3$ source for OPC clinker manufacture is possible or not. In order to synthesize OPC clinker, limestone, shale, converter slag and fly ash were used as main raw materials, and modulus was fixed LSF 91.0, SM 2.60, IM 1.60. The synthesized clinkers were characterized. The Main products of synthesized clinker were C$_3$S, ${\beta}$-C$_2$S, C$_3$A, C$_4$AF as OPC clinker at 1,43$^{\circ}C$. As a result of TG-DTA and burnability index(B.U) analysis of each raw mixtures, the formation temperature of clinker phases was similar and B.I was showed easy burning as 48.6∼51.4.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.55-59
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• 1973

This experiment was carried out to improve on the simple and conventional processing method by studying the characteristics of poultry meat. For the experiment, 20 hens culled and 20 broilers were slaughtered and divided into the following five groups; whole carcass, skinned carcass, debonned carcass, thigh muscle and breast muscle. Each group was ground by the super grinding machine. The results tobtained are summarized as follows; (1) The percentage of the ready-to-cook of cull hens and broilers was $64.32{\pm}2.11,\;67.96{\pm}1.16$, and of the water uptake, $105.43{\pm}1.9,\;104.13{\pm}0.2$, respectively. (2) In the chemical composition, broiler meat showed high moisture content and a little low fat content, as compared with cull hen meat. By groups, whole carcass ground meat contained lower maisture content, and higher fat and ash content than thigh muscle and breast muscle. (3) Thigh muscle and breast muscle group was higher than the other and whole carcass group was lower for the relative WHC and water retention.(4) The higher temperature the higher cooking loss percentage in all groups, and whole carcass group was the highest cooking loss percentage among the all groups.(5) The significant difference was little observed for the relative WHC, water retention and cooking loss percentage by groups between cull hen and Broiler.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.603-613
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• 1995

The purpose of this investigation was to evaluate on the biodegradability, biocompatibility and tissue regenerative capacity of synthetic bioabsorbable membranes in beagle dogs. For animal study, 9 adult beagle dogs were used to examination, on the surgical implantation of membranes and histological analysis. In each animal, the 3rd and 4th premolars of the both sides of the mandible were selected as test teeth. Two types of bioresorbable membranes including "Guidor membrane", "S-membranes" were used to examining for biological activity, and also Gore-tex membranes was used for positive control. Surgically created defects were made in 2 premolars of both sides of the mandible at $3{\times}4mm^2$ in size and tested membranes were implanted in the defected area. A plaque control regimen was instituted with daily tooth brushing with a 0.1% chlorhexidine digluconate during experimental periods. All the experimental animals were sacrificed after 2, 4, and 8 weeks from surgery and undecalcified slides were prepared using the "sawing and grinding" technique described by Donath and Breuner". In biodegradability, all the membranes were started their biodegradation from two weeks after implantation and gradually demolished of their frame morphology from eight weeks. However, demolition of membranes in 8 weeks after implantation was highest in Guidor membranes and followed by S-membranes. Biocompatibilityof two kinds of biodegradable membranes including Guidor and S-mambrane were shown to be well tolerated to the surrounding tissue, and were minimal accumulation of inflammatory cell infiltration around the implanted membranes to compare with Gore-tex membrane. Regeneration of defected alveolar bone was initiated from two weeks of membrane implantation and new bone formation was gradually increased from that time. However, pattern of new bone formation on the defected areas of two kinds of biodegrable membranes was almost similar and quite competitive comparing with Gore-tex membrane. These results implicate that bioresorbable membranes should be highly useful tool for guided tissue regeneration of periodontal defects.

• Journal of Life Science
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• v.28 no.4
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• pp.465-471
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• 2018

Bee pollen is one of many types of alternative remedies, and it has been used for a long time throughout the world. It has numerous health effects, including antifungal, antibacterial, and antioxidant properties, immune modulation, enhanced cell proliferation, and even anti-carcinogenic effects. This study was designed to elucidate the effects of bee pollen on benign prostatic hyperplasia in rodents. For this experiment, we used nano-sized bee pollen produced through wet-grinding technology, thereby the extraction efficiency of the active ingredients in the bee pollen was significantly enhanced. First, We found that nano-sized bee pollen significantly reduced the size of prostates enlarged by chronic testosterone administration. In addition, nano-sized bee pollen significantly reduced the plasma concentration of the prostate-specific antigen (PSA). Interestingly, nano-sized bee pollen did not reduce the testosterone-induced increase in the plasma concentration of prostaglandin $E_2$ ($PGE_2$). The beneficial effects of nano-sized bee pollen in reducing both the size of the prostate and the plasma concentration of PSA was comparable to that of dutasteride. Finally, nano-sized bee pollen did not cause damage in LNCaP cells which are androgen-sensitive human prostate adenocarcinoma cells. Together, these data indicate that nano-sized bee pollen may be able to be used as a good alternative remedy for the treatment of benign prostatic hyperplasia.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1017-1023
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• 1999

Several extraction conditions of mussel were investigated for preparation of the extract as a natural shellfish seasoning. The conditions studied were extraction temperature and time, addition of sodium phosphates and citrate and hydrolysis with commercial proteolytic enzymes. The extracts were prepared by deshelling, grinding and aqueous extraction followed by centrifugation and filtration. Extraction at $90^{\circ}C$ for 40min showed the highest solids yield with less fishy and high umami taste. Among the several phosphates and citrate added, $Na_{3}PO_{4}$ and $Na_{4}P_{2}O_{7}$ at 1% level were most effective in terms of the yield and umami taste. The pH effects showed that pH 10 resulted the highest solids yield of 28% with less fishy taste. Even though the effect of enzymatic hydrolysis was not greatly different among the commercial enzymes tested, Protamex and Protease II were somewhat better than other enzymes in taste. When the mussel were extracted by the combined conditions, hydrolysis with Protamex followed by extraction at $90^{\circ}C$ for 40min with addition of $Na_{3}PO_{4}$ at pH 10, the solid yields increased up to 30% which was about 58% improvement and high intensity of umami taste and less fishy flavor.

• The Journal of Natural Sciences
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• v.15 no.1
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• pp.97-109
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• 2005

This experiment was established to find out the effect of drying methods on the fruit and powder color of red pepper. Hunter's L, a, and b values of the dried fruit were also higher with the cut fruit in comparison with the whole or punched fruit. The Hunter's a value of the pepper powder after drying and grinding was slightly higher for the whole fruit with sun drying, but it was higher for the cut fruit in case of heat drying. The ASTA value was higher when pepper fruits were sun dried. For the heat drying, the value was higher with the drying temperature $60^{\circ}C$.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.3
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• pp.51-57
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• 2010

Thermoelectric properties of the p-type $(Bi,Sb)_2Te_3$, hot-pressed with the $(Bi,Sb)_2Te_3$ powders fabricated by melting/grinding method, were characterized with variation of the hot-pressing conditions. Thermoelectric characteristics of the hot-pressed $(Bi,Sb)_2Te_3$ were also analyzed with addition of $ZrO_2$ as nano inclusions. With increasing the hotpressing temperature from $350^{\circ}C$ to $550^{\circ}C$, Seebeck coefficient and electrical resistivity decreased from 275 ${\mu}V$/K to 230 ${\mu}V$/K and 6.68 $m{\Omega}$-cm to 1.86 $m{\Omega}$-cm, respectively. The power factor decreased with addition of $ZrO_2$ nano powders more than 1 vol%, implying that the optimum amount of $ZrO_2$ nano inclusions to get a maximum power factor would be less than 1 vol%.

• Journal of the Korean Ceramic Society
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• v.39 no.8
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• pp.721-727
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• 2002

In order to overcome trade-off among compositions, process and properties of the glasses with high PbO-base composition for PDP Rib, we studied glass crystallization and crystallization kinetics by Differential Thermal Analysis(DTA). Glass powder was obtained through melting/cooling/grinding, with 3 wt%TiO2 addition for the crystal nucleation and growth in $62PbO-19B_2O_3-10SiO_2-9(Al_2O_3-K_2O-BaO-ZnO)$(in wt%) composition glass. This powder was heat-treated for 1 to 10 h at $445^{\circ}C$ for nucleation. DTA measurements were performed to obtain the crystallization peak with $5∼25^{\circ}C/min$ heating rates. DTA crystallization peak temperature increased with increasing the heating rate and decreased with increasing the heating time. Because the Avrami parameter (n) was approximately 1, the surface crystallization occurred. The maximum nucleation time was 2 h.