Effect of Electron Beam Irradiation on Microbial Growth and Qualities in Astragalus membranaceus

Jin, You-Young,Shin, Hee-Young,Ku, Kyoing-Ju,Song, Kyung-Bin The Korean Society for Applied Biological Chemistr 2006 Journal of Applied Biological Chemistry (J. Appl. Vol.49 No.4

Electron beam irradiation was applied to examine the microbial growth and qualities of vacuum-packaged Astragalus membranaceus, a Korean medicinal herb. Samples were irradiated at dose of 2, 4, 8, 12, and 16 kGy, respectively. Microbiological data on A. membranaceus showed that populations of total bacteria, yeast and mold, total coliforms were significantly reduced with increase of irradiation dose. Populations of microorganisms in A. membranaceus were decreased by 2-3 log cycles at 8 kGy irradiation. Color measurements showed that electron beam treatment caused negligible changes in Hunter color L, a, and b values of A. membranaceus. Sensory evaluations showed that there were no significant changes among the samples. These results suggest that electron beam irradiated A. membranaceus have better microbial safety and qualities, compared with the non-irradiated control.

Notes : Effect of Electron Beam Irradiation on Microbial Growth and Qualities in Astragalus membranaceus

You Young Jin,Hee Young Shin,Kyoing Ju Ku,Kyung Bin Song 한국응용생명화학회 2006 Journal of Applied Biological Chemistry (J. Appl. Vol.49 No.4

수용액에서 γ형 알루미나 표면에 대한 니켈이온(Ⅱ)의 흡착특성

홍교민,김문선,정재관 한국공업화학회 2003 공업화학 Vol.14 No.3

γ형 알루미나의 흡착특성을 구명하기 위하여 본 실험에서는 수용액에서 γ형 알루미나를 흡착제로 이용하여 온도와 pH가 니켈이온(Ⅱ)의 흡착능에 미치는 영향을 관찰하고 알루미나 표면과 니켈이온(Ⅱ) 간의 Langmuir와 Freundlich 흡착등온식과 Lagergren 흡착속도식을 결정했다. 5 g Al_2O_3/L의 조건에서 니켈이온은 10 h에 흡착평형상태에 도달했다. PH 2~6의 범위에서 pH가 증가할 때 흡착량은 급격히 증가하다가 PH 6에서 최대 흡착량을 나타냈으며 pH 6~9의 범위에서는 pH가 증가하여도 흡착량은 일정했다. 온도 20℃에서는 흡착량이 적었으나 30℃에서 급격히 흡착량이 증가하였으며 30~50 ℃의 범위에서는 온도 증가에 따라 흡착량이 완만하게 증가했다. Freundlich 흡착등온식의 결정계수는 0.9489로 Langmuir식의 0.9265보다 높았으며 Lagersen 흡착속도식에서의 k_ad값은 0.0023 h^-1으로 결정계수는 0.9497이였다. In this paper, Langmuir and Freundlich adsorption isotherms, and Lagergen adsorption rate were determined and the effect of temperature and pH on the adsorptivity of Ni(Ⅱ) ions were investigated in order t() stud)'the adsorption characteristics of γ-type alumina. For 5 g Al_2O_3/L, the adsorption equilibrium was obtained in 10 h. The adsorption amount increased rapidly when pH incrteased from 2 to 6, and the maximum adsorption amount was observed at pH 6. For pH 6 to 9, however, the adsorption amount remained constant. The adsorption amount was low at 20℃. However, The adsorption amount increased with increased in temperature; the amount increased rapidly at 30℃ and increased linearly with temperature from 30 to 50℃. The correlation coefficient (R_2) for Freundlich adsorption isotherm was 039489%, and this was higher than that for Langmuir adsorption isotherm of 0.9268%. The adsorption coefficient (k_ad) of lagergen equation was 0.0023h^-1, and the correlation coefficient (R^2) was 0.9497.

Sandblast 처리한 상아질면의 접착에 관한 연구

김교한,나환욱,황성욱 대한치과기재학회 1997 대한치과재료학회지 Vol.24 No.1

Dentin adhesion was studied on sandblasted dentin with 4-META/MMA-TBB resin. The effect of change of air pressure, with or without pretreatment and primer on tensile bond strength, was mainly investigated. In the effect of air pressure at sandblast treatment, the higher pressure showed the increase of tensile bond strength. The pretreatment with 10-3 sloution after sandblast treatment increased tensile bond strength in the almost conditions. Application of primer also increased the tensile bond strength, confirmed the effect of primer application after sandblast treatment. Alumina particle was not found on the dentin surface in the SEM and EDAX examination.

錦江流域 住民의 肝吸蟲 感染에 對한 疫學的 調査硏究

安僑燦,沈雲澤 충남대학교 의과대학 지역사회의학연구소 1982 충남의대잡지 Vol.9 No.1

A study was carried out from the epidemiological aspects on the Clonorchis infection in a certain area along the main stream of the Geum River, which exercised for three times between June 10, 1980 and May 27, 1981. The subjects were chosen 6,950 people who inhabit in 49 Ri along the Geum River. For the beginning of the examination, we had intradermal test for 6,950 people. The next was the stool examinaton for 2,213 people who showed the positive reactive reaction at the first test. Finally we got the response of fheir understanding about Clonorchiasis from 1,929 by the means of questionaire among the 2,213 people who received the stool examination. The follwing results are obtained : 1. From the examination, the 31.8% of the examinee appeared to be positive in the intradermal test. The rate of male(44.7%) showed three times higer than that of female(13.3%). By the age distribution, the postive rate increased sharply in 3rd decade, reached its peak at 4th decade and decreased thereafter. By the areal distribution, the inhabitant in the upper area of the river showed positive rate more highly than the middle or lower area. 2. As a result of stool examination, the egg finding rate of Clonorchis sinensis was 45.2% among the positive reactors by intradermal test. 3. Among the subjects, the 27.3% of them did not know the infection route of Clonorchis sinensis and the 59.9% of them uneducated the health guidance of Clonorchis sinensis.

α+β型 Ti-6Al-4V 合金의 機械的 性質 및 破壞靭性에 미치는 二重溶體化 處理의 影響

金敎漢 慶北大學校 齒科大學 1989 慶北齒大論文集 Vol.6 No.1

Double solution treatment method was used to investigate the effect of microstructure on mechanical properites and fracture toughness of α+β type Ti-6Al-4V alloy. In solution treatment, equiaxed α phase is resulted by 1st solution treatment and acicular α phase by 2nd solution treatment. So two conditions were considered to know the effect of equiaxed and acicular α pahse. First condition is that the amount of acicular α and equiaxed α is changed relatively while total α phase amount is keeped constant. Second one is that the amount of aciclar α phase is changed while equilaxed α ratio is keeped constant. By examined the mechanical properties and fracture toughness of double solution treatmented sepcimens, following results are obtained. 1. Yield strength, elongation and reduction of area have almost same values at double solution treatmented conditions. 2. Fracture toughness shows its the highest value at the condition that the difference between 1st and 2nd double soulution treatment is 100 degree. 3. Fracture toughness of Ti-6Al-4V alloy is affected by the morphology of acicular α phase, such that, when acicular α phase is arranged with block unit, fracture toughness is increased.

치과재료와 환경호르몬

김교한 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.3

Ti표면의 전처리방법이 4-META/MMA-TBB 레진과의 접착강도에 미치는 영향

김교한,서세광 대한치과기재학회 1999 대한치과재료학회지 Vol.26 No.2

The present study investigated the effectiveness of several surface pretreatment methods on the bonding of Ti to adhesive resin. Commercially pure Ti and Ti-6Al-4V alloy were bonded by 4-META/MMA-TBB resin to stainless rods. Each specimen was polished with No. 1.000 sandpaper and then treated with various surface treatment methods, such as 50 ㎛ size of Al₂O₃particles sandblasting, tinplating, silicoating, combination of sandblasting and tinplating and combination of sandblasting and silicoating. The surface of pure Ti treated with sandblasting was roughened to irregular and retentive pattern and aluminum content on the treated surface was increased. The surface morphology treated with tinplating was similar to nontreated one and the surface composition showed almost no change. The surface morphology of silicoating groups was similar to the one of silicoated after sandblasting condition and in both group, carbon content was significantly increased. The surfaces morphology of tinplating was not changed at all. The surface observation results of commercially pure Ti and Ti-6Al-4V alloy specimens were similar, but Ti-6Ai-4V alloy specimens were similar, but Ti-6Al-4V alloy showed more amount of tin precipitations at tinplating groups. Average tensile bond strength of each group was ranged from 21.20 to 31.64 MPa. The tensile bond strength of each group did not show a difference at the 0.05 significance in one-way ANOVA test. Fracture mode of each specimens was almost resin cohesive fracture, and some adhesive fracture-like area was proved to be cohesive fracture in higher magnification. Thus, bonding strength of resin-Ti interface was stronger than that of 4-META/MMA-TBB resin itself.

Clay 또는 은 나노 입자를 함유한 불포화 폴리에스테르 수지의 물성에 관한 연구

인교진,목진규,신동현,김주영 강원대학교 부설 석재복합신소재 제품연구센터 2004 석재연 논문집 Vol.9 No.-

본 연구에서는 불포화 폴리에스테르 수지에 clay 또는 평균 10 nm의 은 나노 입자를 분산시켜 나노 복합체를 제조하여 그 물성 변화를 관찰하였다. clay를 함유한 나노 복합체에 대하여 XRD 분석을 한 결과, clay 층상 구조에 해당하는 회절 피크가 나타나지 않는 것으로 보아 clay의 층간 거리가 벌어져 있음을 알 수 있었다. 그러나 TEM 관찰 결과를 보면 clay 층이 완전히 박리 된 것은 아니고, clay 층 사이에 고분자 사슬이 삽입되어 있는 삽입형 나노 복합체임을 확인할 수 있었다. 또 불포화 폴리에스테르 은 나노 복합체의 경우 수지 내에 은 나노 입자가 고르게 분산되어 있음을 알 수 있었다. clay를 함유한 나노 복합체의 기계적 물성을 DMA로 분석한 결과 저장 탄성률(E´)은 최대 57% 증가함을 보였다. TGA로 분석한 열적 물성에서는 열분해 온도가 최대 18℃ 정도 증가하였다. 이는 clay가 불포화 폴리에스테르 수지의 기계적, 열적 성질에 영향을 주었기 때문인 것으로 판단되었다. 불포화 폴리에스테르 은 나노 복합체의 경우도 은 나노 입자가 고분자 매트릭스와의 상호작용으로 인해 기계적, 열적 물성이 향상되었다. 또, 은 나노 복합체의 경우 은 특유의 성질인 항균성에 있어서 매우 우수한 물성을 나타내었다. In this study, made nanocomposites that dispersed clay or silver nanoparticles of average 10 nm is unsaturated polyester resins and observed change of the properties. According to the result of XRD analysis about nanocomposites containing clay, diffraction peak that correspond to structure of layerd-clay does not appear and could know that exfoliation of distance between layerd-clay. But, seeing TEM image, layerd-clay is not exfoliated perfectly, and could confirm Intercalated Nanocomposites that polymer chain is intercalated between clay layer. Also, it could know that silver nanoparticles is dispersed in unsaturated polyester resins in the case of unsaturated polyester-silver nanocomposites. The result that analyze mechanical properties of nanocomposites which containing clay by DMA showed Storage Modulus(E´) increased maximum 57 %. Also, Pyrolysis temperature increased maximum 18 ℃ in thermal properties that analyze by TGA. Because clay influenced in mechanical and thermal property of unsaturated polyester resins. In case of UP-silver nanocomposites, advanced mechanical and thermal properties because silver nanoparticles interacted with polymer matrix. Also, it appeared properties in Antibacterial that is silver characteristic property in silver nanocomposites.

섭식태도검사(EAT)의 표준화를 위한 예비연구

우마리아,김교헌 충남대학교 학생생활연구소 1996 學生生活硏究 Vol.23 No.-

Garner와 Garfinkel(1982)의 섭식태도검사(Eating Attitude Test-26; EAT-26)를 한국에서 사용하기 위해 사전 점검을 했다. 초등학교 5, 6학년 아동 685명과 그들의 학부모인 성인 남녀 1,186명을 대상으로 척도의 심리측정적 성질을 검토했다. 개별 문항에 대한 문항분석과 전체척도 및 하위척도의 내적 합치도 분석을 하였으며, 연령 및 성별 규준을 예비적 수준에서 마련해 보았다. 또한 선행연구에서 섭식 장애를 가진 사람들이 보이는 심리적 및 신체 병리적 특징들과의 상관을 통해 공존 타당도에 대한 증거를 수집했다. 우리말로 번안된 전체 섭식태도검사의 내적 합치도는 대체로 수용할 만한 수준이었으며, 준거 변인들과의 상관도 예상했던 방향과 대체로 일치했다. 그러나, 일부 하위 요인 척도는 내적 합치도가 만족할 만한 수준에 이르지 못했다. 섭식태도검사의 표준화와 관련된 중요 쟁점들을 논의하였다.