콘크리트의 블리딩에 미치는 혼화재의 영향

황인성,文學龍,金光華,한천구 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

This study is to investigate the influence of contents of mineral admixture on bleeding of concrete. According to the results, as W/B increases, bleeding occurs rapidly at early age regardless of replacement of mineral admixture, and when slump and air content are kept equal, the amount of bleeding decreases proportionately with an increase of replacing ratio of fly ash and blast furnace slag powder. Bleeding speed is highest at 60 minutes after placing concrete, and grow slower after 180 minutes. Bleeding speed also grows high with an increase of W/B, and is lower in the case of fly ash than in the case of blast furnace slag powder.

콘크리트의 블리딩에 미치는 시멘트 제조사 및 분말도의 영향

金恩浩,文學龍,황인성,한천구 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

This study is to investigate the influence of the manufacturing company and fineness of cement on bleeding of concrete. According to the results, as fineness of comment increases, slump and air content of fresh concrete decrease, and setting time is shortened. The amount of bleeding abates with an increase of fineness, and it is confirmed that bleeding does not occur especially in the case of B8000. it is confirmed that bleeding does not occur. Bleeding speed is higher in the case of OPC A than in the case OPC B, and grows low with an increase of fineness. It also becomes highest at about 60 minutes, and shows slow tendency in W/C of 45% in comparison with W/C of 50%. And It is confirmed that relativity between fineness of cement and the final amount of bleeding is very favorable. As the properties of hardened concrete, compressive strength do not make much difference between OPC A and B is little, and increases with an increase of fineness.

olanzapin과 Risperidone의 급성 및 만성 투여기가 흰쥐 전전두피질의 Dopamine 농도에 미치는 영향

문선근,정영철,은홍배,황익근,박태원 大韓神經精神醫學會 2002 신경정신의학 Vol.41 No.1

항정신병약물들이 전전두피질의 세포외 dopamine 농도에 미치는 영향은 이 약물들의 음성 증상에 대한 효과와 관련이 있는 것으로 보고 되고 있다. 따라서 본 연구에서는 최근 국내에서 많이 사용되고 있는 olanzapine과 risperidone을 흰쥐에 급성 및 만성 투여를 한 후, 이들 약물들이 전전두피질의 세포외 dopamine 농도에 미치는 영향을 알아보고자 하였다. 샘플은 생체 내 뇌 미세투석법(in vivo brain microdialysis)을 이용하여 얻었고 샘플내 dopamine의 농도는 전기화학적 검출법(electrochemical detection : ECD)을 사용하는 고압액체크로마토그라피(high pressure liquid chromatography : HPLC)로 측정하였다. 그 결과는 다음과 같다. 1) Olanzapine과 risperidone의 급성 투여는 전전두피질 부취의 세포외 dopamine 농도를 증가시켰으며 증가의 정도는 용량 의존적이었다. 2) Olanzapine과 risperidone의 급성 투여에 의해 전전두피질 부위에 나타난 세포외 dopamine 농도의 최고치는 두 약물간에 유의한 차이가 없었다. 3) Olanzapine과 risperidone의 만성 투여는 전전두피질 부위의 세포외 dopamine 농도를 증가시켰으나 그 증가의 정도가 급성 투여에 비해 모두 감소하는 내성 현상이 보였다. 4) Olanzapine과 risperidone의 만성 투여에 의해 전전두피질 부위에 나타나는 세포외 dopamine 농도의 최고치는 olanzapine과 risperidone에 비해 유의하게 높았다. 이상의 결과들은 Olanzapine과 risperidone의 음성 증상에 대한 임상적 효과가 이들 약물이 전전두피질의 세포외 dopamine 농도를 증가시키는 효과와 관견이 있음을 제시한다. Object : It is reported that the effect of antipsychotics on the extracellular dopamine levels in the prefrontal cortex is related to the their effect on the negative symptoms. Therefore, we investigated the acute and chronic effects of olanzapine and risperidone on the extracellular dopamine concentrations in the prefrontal cortex of rat. Samples were obtained using in vivo brain microdialysis. Method : Dopamine levels in the samples were measured by high pressure liquid chromatography with electrochemical detection. Results : 1) Both the acute treatment of olanzapine and risperidone increased the extracellular dopamine concentrations in the prefrontal cortex, dose-dependently. 2) There was a no significant difference in the maximal change of the extracellular dopamine concentrations in the prefrontal cortex induced by the acute treatment of olanzapine and risperidone. 3) Both the chronic treatment of olanzapine and risperidone also increased the extracellular dopamine concentrations in the prefrontal cortex, but they showed the tolerance effect that the degree of increase was smaller than that of the acute treatment. 4) As for the maximal changes of the extracellular dopamine concentrations in the prefrontal cortex induced by the chronic treatment of planzapine and risperidone, the effect of the former was greater than that of the latter. Conclusion : These results suggest that the effects of olanzapine and risperdone on the negative symptoms are related to the increased extracellular dopamine concentrations in the prefrontal cortex induced by these drugs.

혼화재 종류별 온도 변화에 따른 시멘트 모르터의 응결 및 강도발현 특성

주은희,손명수,차천수,황인성,김성수,한천구 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

In this paper, setting and strength development of cement mortar are discussed under various mineral admixture content and curing temperature. Setting time exhibited an increasing tendency with an increase in curing temperature. Under low curing temperature, use of CKD resulted in a reduction in setting retarding, whereas FA and BS retarded the setting time of cement mortar. For compressive strength, high curing temperature and age leaded to an increase in compressive strength of concrete. Under low curing temperature, the use of CKD resulted in an enhancement of compressive strength at early stage, and exhibited a similar level of compressive strength with plain concrete. For this reason, use of CKD in cold weather concreting has positive effect on strength development at low curing temperature under early age.

2.9% 과산화수소를 함유한 부착형 미백제의 임상적 효능과 안정성에 관한 연구

박은숙,성소래,홍성태,김지은,이소영,황수연,이신재,진보형,손호현,조병훈 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.4

2.9%의 과산화수소를 함유한 시험용 부착형 미백제(Medison dental whitening strip, Samsung medical Co.,Anyang,Korea)를 실험군 피험자 23명, 시험용 미백제에서 과산화수소를 제외한 동일한 제재를 대조약으로 대조군 피험자 24명에게 매일 1시간 30분씩, 2주간 적용하여 임상적 효능과 안전성을 평가하였다. 미백 효과는 Shade Vision, Chroma Mete 및 Vitapan classical shade guide를 이용하여 색변화를 측정하여 다음과 같은 결론을 얻었다. 1. 실험군에서의 전체 치아의 색변화량(ΔE^(*))은 세 가지 측정법에서 모두 대조군에 비해 통계적으로 유의한 차이를 보였고 (p < 0.05). 쉽게 인지할 수 있는 정도였다. 2. 색변화는 색좌표 상에서 명도의 증가와 녹색조 및 청색조로의 변화에 의해 얻어졌다. 3. 치아별로는 어두운 견치의 색변화량이 가장 컸고, 측절치, 중절치 순으로 감소하였다. 4. 47명의 피험자 중 5명이 경도의 과민증을 경험하였으나 곧 완화되었다, 치은염증지수와 전기치수검사 결과 시험 전후에 차이가 없어 안전성을 확인하였다. This study evaluated the effectiveness and safety of an experimental bleaching strip (Medison dental whitening strip, Samsung medical Co., Anyang, Korea) containing 2.9% hydrogen peroxide. Twenty-three volunteers used the bleaching strips for one and a half hour daily for 2 weeks. As control group, the same strips in which hydrogen peroxide was not included were used by 24 volunteers with the same protocol. The shade chang (ΔE^(*), color differnce) of twelve anterior teeth was measured using Shade Vision (X-Rite Inc., S. W. Grandville, MI, USA), Chroma Meter (Minota Co., Ltd. Osaka, Japan) and Vitapan classical shade guide (Vita Zahnfabrik, Germany). The shade change of overall teeth in the experimental group was significantly greater than that in the control group (p < 0.05) and was easily perceivable. The change resulted from the increase of lightness (CIE L^(*) value) and the decrease of redness (CIE a^(*) value) and yellowness (CIE b^(*) value). The shade change of individual tooth was greatest in canine, can smallest in central incisor. The safety of the bleaching strip was also confirmed. 〔J Kor Acad Cons Dent 31(4):269-281, 2006〕

RAPD-PCR을 이용한 누에 계통간 유연관계분석

강은영,김성근,이진성,황재삼,서동상 성균관대학교 생명과학자원연구소 1996 生命資源科學硏究 Vol.3 No.1

We have analyzed the genetic relationship among the silkworm (Bombyx mori) strains using RAPD-PCR. A total of 45 polymorphic RAPD markers amplified from 9 different primers were used to analyze the genetic relationship among the seven silkworm strains. The genetic similarity coefficients among the seven silkworm strains were estimated using the RAPD markers by UPGMA method. The genetic similarity coefficient between 127 and CS120 was 0.261. This value was lower than any other genetic similarity coefficient among the strains tested. And 127-specific RAPD band patterns were observed in 3 primers from 9 polymorphic primers used. This study makes possible phylogenetic identification among the Bombyx mori strains in the molecular level using RAPD-PCR techniques.

광양만으로 유입하는 하천하구에서의 이화학적 특성 : 우수기 직후 유입하천에 따른 영향 effect of inputting rivers after rainy season in summer

김은영,정흥호,정호승,조환익,황주찬,최상원 한국환경과학회 2004 한국환경과학회지 Vol.13 No.9

Physicochemical characteristics of Kwangyang Bay, have been investigated on the effects of inputting rivers just after rainy season in summer 2003. The results ranged from 4.96~8.01 mg/L for DO, 1.16~3.09 mg/L for COD, 7.21~67.71 μM for DIN and 0.12~121.84 μM for phosphate. The COD of Yeosu Area was 1.19~3.09 mg/L, Kwangyang Area was 1.23 ~ 2.76 mg/L. The COD of Wallae cheon in Yeosu Area was 3.09 mg/L and Donghoan in Kwangyang Area was 2.76 mg/L. The reason of high COD might be industrial sewage of organic chemical plants and iron foundry. DIN of Yeosu Area and Kwangyang Area were 7.21--63.43 μM and 8.43 67.71 μM respectively. The average phosphate of Yeosu Area was 23.65 μM. The source of phosphate might be industrial sewages of fertilizer plant and phosphate gypsum stocked with high amounts. The metal concentrations were measured in the range of 1.01~175.10 ㎍/L for Cu, 0.13~1.78 ㎍/L for Cd, 1.13~5.21 ㎍/L for Pb, 1.58~13.57 ㎍/L for Cr and 1.07~20.68 ㎍/L for As. The average Cu concentration was 78.99 ㎍/L in Kwangyang Area. The source of Cu might be industrial sewage of iron foundry. The average Cr concentration of Yeosu Area was 9.07 ㎍/L. That is 2 times higher than Kwangyang Bay 5.74 gg/L, because of sewage of chemical plants.

산이 폴리에틸렌 텔레프텔레이트 섬유의 알칼리 가수분해에 미치는 영향

都成國,曺煥,黃恩慶 東亞大學校 大學院 1989 大學院論文集 Vol.14 No.-

To control the weight loss in the treatment of Poly(ethylene terephthalate) (PET) fabric with NaOH, HCl and CH( )COOH, as regulating reagent, were added to the 0.5 MNaOH solution. The mixing ratio of acids to 0.5M NaOH were varied. PET fabrics were treated with aqueous solutions of mixture of acids arid NaOH under different contritions. The weight loss of PET fabric, the rate of weight loss, the apparent activation energy(Ea), the handle value, the eroded surface of treated PET fiber, and the effect of salts such as NaCl, CH( )COONa, and NH( )Cl on the weight loss were discussed. The addition of acids to a fixed concentration of NaOH deceased weight loss of PET fabric because of formation of salts but the weight loss of PET fabric treated with corresponding concentrations of NaOH to the content of acids added were lower than those treated with the aqueous solutions of mixture of CH( )COOH and NaOH and higher than those treated with the aqueous solutions of mixture of HCI and NaOH. Especially, as the treatment time elapsed CH( )COONa formed by addition of CH( )COOH to NaOH was hydrolyzed to NaOH and undissociated CH( )COOH and hydrolyzed NaOH contributed to the increase in the weight loss of PET fabric. The addition of NaCl to NaOH accelerated the reaction of OH- with PET greatly, the addition of NH( )Cl decreased the weight loss of PET fabric, and the addition of CH( )COONa somewhat increased the weight loss. It was thought that the very noticeable fact that the addition of NaCl to NaOH promoted the hydrolysis of PET by NaOH would contribute to the conservation of energy and NaOH in the weight loss finishing process of PET fabric. The eroded surface of PET fiber was independent of the differnce in the kinds of acids and salts added.

농작물 해충 및 진균류 방제를 위한 방선균의 분리 및 동정

이은정,강경돈,황교열,김두호,김신덕,성수일 한국잠사학회 1998 한국잠사곤충학회지 Vol.40 No.1

Twenty seven out of ca. 5,000 actinomycete strains, which were isolated from soil collected throughout the country, showed antimicrobial effects against fungi, Rhizopus stronifer (ATCC6227a), Rhizoctonia solani (KCCM 11271) and yeast, Candida albicans(ATCC10231). From these antifungal microorganisms, we further selected seven strains which seemed to produce insecticidal substances with in vivo test, using silkworm, Bombyx mori and beet armyworm, Spodoptera exigua. Morphological and biochemical experiments revealed that three strains out of seven were streptomyces. Further investigations on the physical and chemical properties of these antifungal and insecticidal substances are now in progress.

오존을 이용한 하수슬러지의 감량화와 안정화

이창근,황은주,강성재,빈정인,이병헌 한국물환경학회 2004 한국물환경학회지 Vol.20 No.3

In this study, ozone was adopted for the reduction and stabilization of waste sludge from the municipal sewage treatment plant. The waste sludge used in the experiments was primary sludge, excess sludge and a mixture of the two. The sludge cells and flocs were disrupted by ozonation resulting in the reduction of TSS and VSS concentrations. In the case of the primary sludge with a concentration of 20 gTS/L, the TSS and VSS concentrations were reduced 28%, 33% and the TCOD concentration was reduced 20% respectively. The consumption of ozone was 0.18 gO₃/gSS. In the case of the excess sludge with a concentration of 7.5 gTS/L, the TSS and VSS concentrations were reduced 37%, 41%, and the TCOD concentration was reduced 19% respectively. The consumption of ozone was 0.33 gO₃/gSS. In the case of the mixed sludge of 9.3 gTS/L, the TSS and VSS concentrations were reduced by 45%, 53%, and the TCOD was reduced 26% respectively. The desirable consumption of ozone was 0.27 gO₃/gSS. As ozonation proceeded, the level of SCOD increased due to the release of intracellular materials. However TCOD was reduced due to mineralization resulting from the transformation of organic materials to inorganic materials.