• 대한약리학회지
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• 제8권2호
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• pp.63-69
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• 1972

The effects of omission of buffers from Krebs-Ringer medium on contractile activity, membrane potentials and ATP content of electrically stimulated isolated rat atria were investigated. 1) Contractile status: A rapid and marked depression of the contractile activity of atria occurred when buffer-free medium was substituted for the normal Krebs-Ringer medium. 2) Electrical status: The omission of buffers from medium did not alter the resting or action potential magnitudes of atria. However, the action potential duration was on initial increase followed by a decrease in the buffer-free medium. 3) ATP concentration: The omission of buffers from medium resulted in a marked decrease in the ATP levels of atria. It has been also found in the present study that bicarbonate buffer plays an important role for the maintenance of the contractility and ATP levels of the heart. The contractile depression by the omission of buffers was not directly associated with electrical alterations in resting or action potentials of the heart. In the absence of bicarbonate-buffer, glucose no longer plays to maintain the contractile activity and the ATP levels of rat atria.

• 한국식품영양과학회지
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• 제26권4호
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• pp.569-574
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• 1997

게껍질의 김치 보존성 증대 효과에 대한 원인을 보다 구체적으로 검토함과 동시에 첨가시 문제점으로 대두된 비린맛을 줄여 볼 목적으로 CSP(crab shell powder)의 입도를 100 mesh이상으로 하여 가스상 50ppm의 오존으로 1시간 동안 처리하여 비린내를 제거시킨 것에 대하여 중화율을 측정하는 동시에 김치에 첨가하였을 때 관능적 품질과 pH와 산도 변화에 미 치는 영향을 조사하였다. 그 결과 CSP를 김치에 2% 정도 첨가함으로서 산미에 의한 평가로서는 1$0^{\circ}C$에서 33일 이상의 보존이 가능하였고, pH에 의한 평가로서는 40일 이상의 보존이 가능하였다. CSP는 김치의 숙성 중 강한 중화 작용을 하였으며 발효 25일 이후에는 완충효과를 나타내었다. CSP의 중화작용을 실험한 결과 CSP 3%는 젖산 2%용액을 완전히 중화시킬 수 있었으며 일시에 중화시키지 않고 서서히 녹아 나와 중화작용을 하였다. CSP 2% 첨가시의 완충작용으로 흡수할 수 있는 젖산량은 0.07~0.3%이였다. 그러나 CSP의 첨가량을 2% 정도로 할 경우 종합적인 맛의 평가치가 다소 떨어져 맛에 대한 보완연구가 요망되었다.

• 한국식품영양과학회지
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• 제12권3호
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• pp.289-296
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• 1983

식품(食品)의 정미성(呈味性)에 대하여 연(憐) 함유량(含有量)과 그의 완충작용(緩衝作用)에 관한 관계(關係)를 규명(糾明)하기 위하여 식물성(植物性) 및 동물성(動物性)에 식품(食品) 28품목(品目)에 대한 실험(實驗) 및 통계학적(統計學的) 처리(處理)를 한 바, 다음과 같은 결과(結果)를 얻었다. 일반적(一般的)으로 동물성(動物性) 식품(食品)이 식물성(植物性) 식품(食品)보다 연(憐)의 함유량(含有量)이 높았으며, 또한 연(憐) 함유량(含有量)이 높은 식품(食品)이 더 큰 완충작용(緩衝作用)을 나타내였고, 아울러 거의 대부분 완충작용(緩衝作用)이 큰 식품(食品)은 정미성(呈味性)이 양호(良好)하였다. 따라서 정미성(呈味性) 완충작용(緩衝作用)의 능력(能力)과 관련(關聯)되는 것으로 사료(思料)된다.

• 한국세라믹학회지
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• 제27권5호
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• pp.684-692
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• 1990

Ultrafine magnetite powder for the ferromagnetic fluid was prepared by an addition of alkaline solution to the solution containing Fe2+ and Fe3+ ions at 6$0^{\circ}C$. The optimum condition of the magnetite synthesis was delineated by examining such various physico-chemical properties as Fe2+/Fe+3 ratio in the powder, phase characteristics, MHC and $\sigma$max. A new scheme for the steric stabilization of colloidal dispersion was proposed using the concept of the buffer group action for the increased interfacial density of the stabilizing moieties at colloid particle/dispersion medium interface. The proposed concept was successfully applied to the preparation of the kinetically stable kerosinebased ferrofluid using Tween and Span as dispersants. In the dispersion of magnetite particles in a kerosine, Tween(polyoxyethylene sorbitan oleate) acts as a primary stabilizer which provides an anchor group, whereas Span(sorbitan oleate) can be classified as a secondary stabilizer which adsorbs on the surface of magnetite particle through the action of the buffer group. Dispersion studies using various quantities of Tween and Span supported the concept of the buffer group action for increased dispersion characteristics of the kerosine based ferromagnetic fluid.

• 한국식품영양과학회지
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• 제17권4호
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• pp.358-364
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• 1988

pH조정제 sodium malate buffer(SMB)가 김치의 숙성에 미치는 영향을 검토하기 이하여 소금농도별 ($0{\sim}6%$) 및 SMB첨가농도별($1{\sim}2%$)로 김치를 담그고 숙성중 질적변화를 조사하였다. 그결과 소금농도가 증가함에 따라 김치의 숙성이 지연되었고 SMB를 첨가한 경우 및 그 첨가농도가 높은 경우가 더욱더 숙성이 지연되었다. 산도는 SMB형 가구가 오히려 높았으나 관능검사결과 산도와 반비례하여 SMB 첨가에 의한 완충능에 기인된 것으로 판단되었으며 김치의 숙성이 진행됨에 따라 완충능은 더욱 증가하였다. 소금 2% 첨가김치에 SMB의 1%첨가한 경우 2% 소금만을 첨가한 경우에 비해 $25^{\circ}C$에서 약 36시간 숙성이 지연되었으며 소금 농도가 비교적 높은 4% 첨가 김치보다는 약 12시간 숙성이 지연되었다.

• 아시안잔디학회지
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• 제9권1호
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• pp.81-89
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• 1995

The variations of the soil texture, $SiO_2$ /$Al_2$$O_3$ ratio, buffer action, exchangeable base, ex-changeable hydrogen, and mineral nutrients were investigated to estimate the grade of the soil fertility of the soil derived from the different parent rocks such as the granite in Kwangnung and the basalt in Chejudo. The results investigated were showed as follows : Basalt soils in Chejudo belong to sandy clay, light clay and sandy clay loam, while gramite soils in Kwangnung sandy loam. The $SiO_2$ /$AI_2$$O_3$ ratio of the grassland in Chejudo was 1.11 and that of the oak forest soils was 1.24, while granite soils in Kwangnung 1.54 and 1.46, respectively. The buffer actions of ba-salt soils against the N /10 HCI and $Ca(OH)_2$ were stronger than those of granite soils. The $SiO_2$/$Al_2$$O_3$ + $Fe_2$$O_3$ ratios of grassland and oak forest soils of basalt in Chejudo showed 1.10 and 1.24 respectively, while those of the grassland and oak forest of Kwangnung 1.44 and 1.33. The base exchange capacity of basalt soils which has higher value of exchangeable hydrogen was stronger than that of granite soils. But the base saturation of granite soils showed higher value than that of basalt soils. Water contents of basalt soils in Chejudo was lower than that of granite soils fo Kwangnung Basalt soils in Chejudo contain still more humus and total nitrogen than gran-ite soils in kwangnung, The amount of available nitrogen, available phosphorus and exchangeable calcium of granite soils were more than that of basalt soils, Therefore, estimating the soil fertility, granite soils in Kwangnung is higher than that of basalt soils in Chejudo.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.436-440
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• 2006

Diffuse pollution has been considering as a major source of the quality deterioration of water resources. The establishment of riparian vegetation strips of buffers along those areas of water bodies is used to reduce the threat of diffuse pollution. Remote sensing offers a means by which critical areas could be identified, so that subsequent action toward the establishment of riparian zones can be taken. Even though the principal purpose of this research comes from the feasibility of the imagery of KOMPSAT-2 satellite, Landsat TM satellite data, which has 7 bands, are used to characterize the land cover for the study area on the behalf of KOMPSAT-2. This investigation focuses on the assessment of the existing riparian buffer zones for a portion of the upper Geum river watershed from the viewpoint of pollution mitigation by riparian vegetation strip establishment. Through comparing the delineation of riparian buffer zones developed with the existing zones established by the government, we can find the critical distortion points of the existing riparian buffer zone.

• 대한약리학회지
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• 제17권2호
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• pp.17-22
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• 1981

Guinea-pig ileum을 naloxone을 가(加)하거나 가(加)하지 않은 전해질(電解質) 농도(濃度)가 다른 modified Krebs-Henseleit bicarbonate buffer solution에 $4^{\circ}C$에서 24시간 incubation한 다음, morphine의 수축(收縮) 억제작용(抑制作用)으 관찰(觀察)하여 다음과 같은 성적(成績)을 얻었다. 1) Incubation 자체(自體)로써 morphine의 작용(作用) 강화(强化)되었다. 2) Incubation media 내(內) 전해질(電解質) 변동(變動)은 $Na^+\;75mM$ 군(群)과 $K^+2.9mM$ 군(群)에서는 morphine의 작용(作用)이 강화(强化)되었고, $Ca^{++}\;3.6mM$ 군(群), $Mg^{++}$ free 군(群)과 $Mn^{++}\;0.2mM$ 군(群)에서는 약화(弱化)되었다. 3) Incubation media내(內) naloxone은 morphine의 작용(作用)을 강화(强化)하였다. Incubation media 내(內) naloxone을 가(加)하고 전해질(電解質)을 변동(變動)시킨 실험(實驗)에서 $Na^+\;75mM$ 군(群), $K^+2.9mM$ 군(群)과 $Ca^{++}3.6mmM$ 군(群)에서는 naloxone에 의(依)하여 morphine 작용(作用)이 약화(弱化)되었고, $Mg^{++}$ free 군(群)과 $Mn^{++}\;0.2mM$ 군(群)에서는 강화(强化)되었다. 4) Naloxone에 대(對)한 $pA_2$치(値)는 전군(全群)에서 변동(變動)이 없었다. 5) 이상(以上) 실험성적(實驗成績)은 naloxone opiate receptor에 대(對)한 작용외(作用外)에 세포막 또는 근세포수축기구(筋細胞收縮機構)에 영향(影響)을 미처 morphine의 작용(作用)에 영향(影響)을 줄 수 있음을 시사(示唆)한다.

• 대한원격탐사학회지
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• 제22권5호
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• pp.445-449
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• 2006

Diffuse pollution has been considering as a major source of the quality deterioration of water resources. The establishment of riparian vegetation strips or buffers along those areas of water bodies is used to reduce the threat of diffuse pollution. Remote sensing offers a means by which critical areas could be identified, so that subsequent action toward the establishment of riparian zones can be taken. On the behalf of KOMPSAT-2 satellite imagery as a high resolution spatial data, Landsat TM satellite data are used to aquire the land cover for the riparian buffers studied. This investigation aims to assess the riparian buffers established on the upper Geum river as a pollution mitigation. Through comparing the delineation of riparian buffer zones developed with the existing zones established by the government, we can find the critical distortion points of the existing riparian buffer zone.

• 한국자동차공학회논문집
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• 제8권6호
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• pp.165-175
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• 2000

In order to improve the function of a door seal, its section design technique is discussed in this study, Its roles are prevention of an inflow of dusts, noise interception, insulation, wateproof, and the vibroisolating action which reduces vibration between the body and the door of a car while running, and the buffer action which sustain the proper reacting force as the door is closed. In this study, the optimal cross section of a door seal is designed using nonlinear finite element analysis (commercial finete element analysis program EASi-SEAL) and tables of orthogonal arralys with respect to relations between door and door seal to secure the satisfactory airtight property with the minimum force to shut the door.