• Applied Biological Chemistry
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• v.36 no.5
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• pp.364-369
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• 1993

Triton X-100 enhances to a marked extent the analytical sensitivity of the nitrobluetetrazolium (NBT) reduction method for the assay of superoxide$(O^-_{\.{^.2}})$ production. In the present work, it was attempted to elucidate the physicochemical nature of this Triton X-100 effect, focusing on not only the surfactant-caused stabilization of the water-insoluble formazan colloid but also the kinetic competition between the $NBT-O^-_{\.{^.2}}$ reaction and the autodisproportionation of concommitantly occuring in aqueous media. The measurements of formazan and $H_2O_2$ formed in a number of reaction systems, as prepared by vortex-mixing potassium superoxide dissolved in an aprotic solvent with aqueous solutions of NBT, revealed that Triton X-100 exerts its effect both through preventing formazan colloid from aggregation and thereby increasing the formazan absorbance and through suppressing the autodisproportionation reaction of $O^-_{\.{^.2}}$. It also turned out that the relative shares of the colloid stabilization effect and the kinetic effect in the contribution to the sensitivity amplification of the NBT method are dependent upon the reaction conditions, particulary the molar concentration ratio of NBT to $O^-_{\.{^.2}}$ in the reaction systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.12-16
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• 2002

In this study, the physicochemical properties of warty black and glutinous rice flours were compared. Crude protein content of waxy black rice flour (9.01%) was higher than than of glutinous rice flour (7.54%). Most mineral contents of waxy black rice flour were higher than those of glutinous rice flour. The major fatty acids in the waxy black and glutinous rice flours were oleic acid (38.57% and 36.95%) and linoleic acid (38.60% and 39.10%). The major detected amino acids of both samples were aspartic acid, glutamic acid and arginine. Water binding capacity of waxy black rice flour (93.26%) was higher than that of glutinous rice flour (87.42%) . Swelling powers and solubilities of waxy black rice flour were lower than those of glutinous rice flour in according to increasing temperatures. Maximum absorbance wavelength (λ$_{max}$) and absorbance at 625 nm were similar between both samples. X-ray diffraction patterns of both samples showed traditional A type as Peaks 2$\theta$ at 15.1$^{\circ}$, 17.1$^{\circ}$, 18.0$^{\circ}$and 23.2$^{\circ}$. The relative crystallinities of waxy black and glutinous rice flours were 0.40 and 0.41, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.281-287
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• 2009

An eruption failure can be observed for child and adolescent periods when the primary dentition is changed to the permanent dentition through the mixed dentition frequently. The eruption failure can lead to miss erupting times of the tooth, then it will cause a lot of problems including root resorption, esthetic problem, transposition of adjacent tooth, malocclusoin and etc. Especially, the maxillary first molar is importantly concerned with occlusion and growth and is an essential tooth for development and maintenance of occlusion. So, it is a momentous part of more proper occlusal management to find these abnormal cases at the early stage and solve the problems. The sorts of eruption failures of the maxillary first molars can be divided into delayed eruption, impaction and the primary retention and the secondary retention. When physical obstacles cause impaction, first of all they must be removed then we can treat the impaction with observation after removal, surgical exposure or orthodontic traction. If the source of impaction is an ectopic eruption, the treatment can be a brasswire, a pendulum appliance, a space maintainer or space regainer after the extraction of the second deciduous tooth and etc. These cases are made a diagnosis of eruption failures of the maxillary first molars in mixed dentition period and have good prognosises after my treatments. So I reported them.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.245-253
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• 2014

BACKGROUND: Oyster shell(OS) is alkaline with pH 9.8, porous, and has high concentration of $CaCO_3$. It could be used as an alternative of lime fertilizer to immobilize cadmium(Cd) in heavy metal contaminated arable soil. Therefore, this study has been conducted to compare effects of calcium(Ca) materials [OS and $Ca(OH)_2$] on Cd extractability in contaminated soil and determined mechanisms of Cd immobilization with OS. METHODS AND RESULTS: Both Ca materials were added at the rates of 0, 0.1, 0.2, 0.4, and 0.8% (wt Ca wt-1) in Cd contaminated soil and the mixtures were incubated at $25^{\circ}C$ for 4 weeks. Both Ca materials increased pH and negative charge of soil with increasing Ca addition and decreased 1N $NH_4OAc$ extractable Cd concentration. 0.1 N HCl extractable Cd concentration markedly decreased with addition of OS. 1 N $NH_4OAc$ extractable Cd concentration was related with pH and net negative charge of soil, but not with 0.1 N HCl extractable Cd concentration. We assumed that Cd immobilization with $Ca(OH)_2$ was mainly attributed to Cd adsorption resulted from increase in pH-induced negative charge of soil. Scanning electron microscope (SEM) images and energy dispersive spectroscopy(EDS) analyses were conducted to determine mechanism of Cd immobilization with OS. There was no visible precipitation on surface of both Ca materials. However, Cd was detected in innerlayer of OS by EDS analyses but not in that of $Ca(OH)_2$. CONCLUSION: We concluded that Cd immobilization with OS was different from that with $Ca(OH)_2$. OS might adsorbed interlayer of oyster shell or have other chemical reactions.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.105-111
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• 1999

When the preparation method of iron silicide films possess the annealing process, the interfacial state of the films is not fine. The good quality films were obtained as the plasma was used without annealing processing. Since the injected precursors were various active species in the plasma state, the organic compound was contained in the prepared films. We confirmed the formation of Fe-Si bonds as well as the organic compound by Fe and Si vibration mode in Raman scattering spectrum at $250cm^{-1}$ and Ft-IR. Because of epitaxy growth being progressed by the high energy of plasma at the low temperature of substrate, iron silicide was epitaxially grown to ${\beta}$-phase that had lattice structure such as [220]/[202] and [115]. Band gap of the prepared films had value of 1.182~1.174 eV and optical gap energy was shown value of 3.4~3.7 eV. The Urbach tail and the sub-band-gap absorptions were appeared by organic compound in films. We knew that the prepared films by plasma were obtained a good quality films because of being grown single crystal.

• Journal of Korea Water Resources Association
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• v.36 no.6
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• pp.1013-1023
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• 2003

This study was performed to improve water quality of stream by applying hydraulic structures (weir and river bed material) made of porous concrete. The physical and chemical characteristics of porous concrete were measured to estimate application possibility of it in hydraulic structures and it was considered as a proper material for the hydraulic structures. In the results of comparison for the component of matters attached on the hydraulic structures made of porous and ordinary concrete, DW (dry weight) amount attached on porous concrete was 1.6 times higher than that on ordinary concrete under the condition of the same flow rate but influence by flow rate (difference of 10 times) was not shown. Therefore, we could understand that the material of media was more important in DW amount than flow rate. The rate of AFDM (ash free dry mass) to DW also was more at porous concrete than at ordinary concrete. Especially, the high rates of nitrogen and phosphorous in matters attached on porous concrete verify that they were removed by assimilation, adsorption and metabolism of periphyton. The removal percentage of SS, BOD, COD, T-N and T-P by hydraulic structures applying porous concrete compared with ordinary concrete was increased by 34.6%, 36.9%, 33.9%, 18.3% and 21.6%, respectively. Therefore, applying porous concrete to hydraulic structure is expected to contribute to improvement of stream water quality.

• Korean Journal of Materials Research
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• v.4 no.1
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• pp.3-8
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• 1994

Recently, sound and mechanical vibration are becoming important problems in our life. In the present study, the measurement of vibration absorption characteristics of barium titanate ceramics and the investigation of its relationship to microstructures were carried out. The barium titanate ceramics is expected to be better vibration absorption material owing to its chemical and physical stability than other conventional vibration absorbers like glasswool board. Barium titanate ceramics were prepared by sintering fiberous $BaTiO_{3}$ crystallites in order to enhance the vibration absorption characteristics. The fiberous $BaTiO_{3}$ ceramics were prepared through the ionic exchange after the preparation of fiberous $K_2Ti_4O_9$ with 0.2$\mu\textrm{m}$, 1.2$\mu\textrm{m}$, 2.0$\mu\textrm{m}$, diameter length by KDC method. The fiberous crystallites were oriented in a plane perpendicular to the press direction and sintered. The investigation of the grain diameters of the sintered ceramics, equivalent factor, electromechanical coupling factor($k_1$), and the generated voltage(V) shows that the grain's diameter decreases with the increase of the diameter of the used fiberous crystallites. The vibration absorption increases the crystallites' diameter. That means that the vibration absorption increases with the internal friction of grain boundary. Which was identified by the investigation of the equivallent circuit.

• Conservation Science in Museum
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• v.10
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• pp.43-61
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• 2009

The Buyeo National Museum was requested conservation treatment for wooden objects excavated from three Baekje archeological sites: Neungsan-ri, Ssangbuk-ri, and Gungnamji Pond. Prior to conservation treatment, analysis was conducted to identify the species used. The results of the analysis revealed wood from diverse species of trees including Hard pine, Cryptomeria japonica D. Don, Zelkova serrata Makino, Quercus spp., Platycarya strobilaceae S. et Z., Castanea spp., Torreya nucifera S. et Z., Taxus cuspidata S. et Z., and Salix spp. A high percentage of the objects were made of Cryptomeria japonica D. Don., a species native to Japan, which indicates that exchange with Japan was active at that time. Among the wooden objects, we analyzed lacquer fragments from six pieces of lacquerware, and the characteristics of the lacquer fragments were peculiar to specific artifacts. Most of the fragments were thicker than 100 ㎛. Pure lacquer and mixed black pigment were used. Infrared spectroscopy of the lacquered wooden fragments revealed that they had a very similar absorption band as refined lacquer, confirming that they were painted with lacquer. For their conservation, we immersed the objects in a high molecular weight aqueous solution of PEG#3,350 (10% → 50%) to strengthen them before vacuum freeze-drying.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 1997.06b
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• pp.13-14
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• 1997

영지의 약리효과는 triterpenoid계의 저분자와 polysaccharide인 고분자로 대별할 수 있다. 저분자 물질은 항염증작용, 항알러지작용, 간암세포 성장 억제작용, 혈압 강하작용, 혈소판 응집저해작용 등이 있으며, 고분자 물질은 혈압강하작용, 정혈작용, 고지혈증 개선작용, 혈당 강하작용, 면역 증강작용 및 항종양작용 등이 있는 것으로 알려졌다. 현재까지의 영지에 관한 연구는 주로 자실체에 대한 연구가 주류를 이루고 있으며 이들의 산지, 환경조건, 채집시기 및 실험자들에 따라 약리 효과 등에 많은 차이가 있다. 이들에 대한 효과가 영지의 대표적 약리효과라고 언급하기엔 부족한 점이 많으므로 약리효과가 우수하고 일관성이 있는 영지 유래 다당류를 얻기 위한 방법으로서는 균사체의 대량배양법 및 분리방법이 확립 되어야만 한다. 본 연구에서는 새로운 항암활성 다당류의 개발을 위해 국내 자생 영지를 채집하여 검색 및 계통적 분류를 행하였으며 분리된 균주의 최적 액체배양 조건, 다당류 분리 조건, 다당류의 물리화학적 특성 및 약리활성 등에 관한 연구를 실시하였다. 그 중 약리활성이 우수한 G- lucidum IY009 균주를 선발 하였다. 구조적 특징과 종양 면역 활성과의 관계 규명을 위해, G- lucidum IY009 배양균사체로부터 다당류를 T-AS, U-AS, M-AS, S 및 H로 분획 하였다. 추출조건에 따른 다당류 GLG의 수율은 열수 추출 분획이 2.98g/l로 가장 높았으며, U-AS및 T-AS에서 각각 2.32g/l, 2.07g/l이었다. GLG의 특성을 조사하기 위하여 수용성과 비수용성으로 분리한 결과 수용성 분획은 비수용성 분획보다 높은 당 함량을 나타냈으며, T-AS는 70.3%의 당과 7.8%의 단백질로 구성 되었다. GLG 대부분의 분획들은 60~93%의 glucose로 구성된 다당류 이었으며, 주로 $\beta$-glucose로 구성된 다당류 이었다. 아미노산은 Asp 및 Glu의 산성 아미노산과 Ala, Leu 등의 함량이 높게 나타났으며, 비알칼리 추출물에서 Ser과 Thr의 함량이 높게 나타났다. 다당류 T-AS는 평균 분자량이 2,000 kD와 12kD에서 주 peak를 나타냈으며, 수용성 분획의 평균 분자량은 12kD이고 비수용성 분획은 36~2,000 kD의 평균 분자량 분포를 갖는 것으로 나타났다. IR과 NMR 분석 결과 890 cm-1에서 흡수 peak를 나타내어 $\beta$-(1,3)0glucan과 $\beta$-(1,6)-glucan의 구조를 갖는 다당류로 확인 되었다. T-AS 분획은 C:H:O:N의 함량비가 38.9:5.7:49.6:1.84%이며, 이 물질의 융점은 163 $^{\circ}C$로 연한 갈색을 나타낸다. 분리된 GLG의 항암활성 기전 규명을 위해, in vivo 항암실험, 항보체 활성능, 항체 생성능, serum protein 분비능, 대식세포의 탐식능과 활성능 및 세포간 물질 분비 등의 상관관계를 조사하였다. 다당류 GLG 분획물들 가운데 항보체의 활성이 높았던 분획은 sarcome 180에 대한 항암 활성이 높게 나타났다. 다당류 T-AS의 보체 활성화 기작은 classical과 alternative complement pathway의 양 경로를 통해 활성화 되었다. T-AS 분획은 mouse내의 특정 혈청단백을 증가시켰으며, 항체 생성능의 증가가 관찰되어 effect T 세포의 활성화가 나타나고 있음을 알 수 있었다. T-AS는 생체내 투여시에 대식세포의 탐식능이 증진되었으며, 대식세포 기능 저해제에 의한 대식세포의 기능 저해 현상이 회복되었다. 이와 같은 결과들로부터, T-AS의 항암 활성은 활성화된 보체 성분 및 당 수용체들이 존재하는 대식세포의 개입을 시사한다.

• Journal of the Korea Computer Graphics Society
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• v.23 no.1
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• pp.9-16
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• 2017

Simulating the clumping and stiffness of wet hair or fur is a challenging problem. The dynamics of wet hair or fur is characterized by the clumping and stiffness at the tip, which is easily seen in running animals or headbanging scenes. Existing methods address these phenomenon within pre-set scenarios. But there is no consensus on the method of depicting the details of wet hair. Hence, the present paper proposes a new method of modeling the clumping and stiffness of wet hair or fur. Previous studies focused on modeling the absorption of water into hair or fur, whereas this paper highlights a realistic simulation of wet hair. Unlike dry hair strands, wet hair strands adjacent to one another are subjected to the clumping force and gather together, while at the same time becoming stiff as the saturation of water increases. The proposed method builds on the surface tension model based on SPH (smoothed particle hydrodynamics) to simulate the clumping force and to adjust the hair elasticity by giving stiffness constraints. The present method enables a realistic simulation of wet hair by maintaining the clumping force of the wet hair even in dynamic motions, and by simulating the stiffness of hair in line with water saturation.