• Title/Summary/Keyword: Lewis form

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Antitumor Activity of Lactobacillus casei against Sarcoma 180 and Lewis Lung Carcinoma in Mice (생쥐에서 Sarcoma 180 및 Lewis Lung Carcinoma에 대한 Lactobacillus casei의 항암 효과)

  • 배형석;백영진;윤영호
    • Microbiology and Biotechnology Letters
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    • v.21 no.3
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    • pp.247-255
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    • 1993
  • Antitumor activity of Lactobacillus casei YIP 9018(LC9018) was studied in mice by using sarcoma 180(S-180) and Lewis lung carcinoma (3LL). Following the eatablishment of in vivo tumor models such as ascites form S-180, solid form S-180 and 3LL for estimating antitumor activity of Lactobacilli, optimal dose and injection route of heat-killed LC9018 for supperssion of local tumor were examined. Administration of 100ng/mouse of LC9018 significantly inhibited the growth of ascites form S-180, solid form S-180 and 3LL.

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On the Virtual Inertia Coefficient of the Chine-type Ship in Vertical Vibration (Chine형선(型船)의 상하진동(上下振動)에 대(對)한 가상관성계수(假想慣性係數)에 관(關)하여)

  • K.C.,Kim;J.J.,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.9 no.1
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    • pp.1-6
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    • 1972
  • To contribute towards more accurate estimation of the virtual coefficient for the vertical vibration of the chine-type ship, experimentally obtained three-dimensional correction factors, J, of added mass of prismatic beams having cross section shape of hypotrocoid characters, slightly concaved Lewis form and elliptic form are investigated in connection with the applicability of an approximate analytical calculation method compared to that proposed by T. Kumai[6] for the Lewis form cylinders, and synthetically in compared with the experimental works on various cross section shapes of the other type by L.C. Burril et al[8] and the analytical works on the ellipsoid of revolution by F.M. Lewis[1] and J.L. Taylor[2]. The experimental results show that the aforementioned analytical method gives, unlike that for the Lewis form cylinders, considerably larger J-values for the chine-type cylinders, and that the influence of the character of the cross section shape on J-values is not remarkable in practical sense. Finally, considering in synthesis the experimental results on prismatic beams, the Burril's works on palabolic plan form and elliptic plan form, and that the chine-type ship usually has a hull form of transom stern, it is fairly safe to say, at the present stage, that adoptation of the Taylor's J-values will not results in any large error in estimation of the virtual inertia coefficients of the chine-type ships.

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On The Added Mass and Damping of Chine Sections in Heaving Oscillation -Comparisons with Equivalent Lewis Section- (배골형단면주상체(背骨型斷面柱狀體)의 상하동요(上下動搖)에 있어서의 부가질량(附加質量)과 감쇠력(減衰力)에 관(關)하여)

  • J.H.,Hwang;Yoon-Ho,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.10 no.1
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    • pp.33-44
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    • 1973
  • Chine형 선체단면 주상체의 자유표면에서의 상하운동에 수반되는 부가질량과 감쇠력을 Ursell-Tasai 방법에 의하여 계산하였다. Chine형에서 구하여진 결과는 같은 선체단면적 계수와 반폭흘수비를 갖는 등가 Lewis형의 결과와 비교하였고 선체단면의 형상이 부가질량 및 감쇠력에 미치는 영향을 고찰하였다. Chine형과 등가 Lewis형 선체단면 주상체에 파고가 일정한 횡파가 입사할 때의 상하운동을 고찰하였다. 이상과 같은 계산 및 고찰을 통하여 다음 결과를 얻었다. 1) 자유표면이 부가질량에 미치는 영향은 chine형이 등가 Lewis형단면보다 큰 값을 갖는다. 2) 선체단면적계수와 반폭흘수비가 같은 경우에 감쇠력의 크기는 Lewis form, single chine, double chine순서이다. 3) 선체단면계수와 반폭흘수비는 상하운동에 가장 큰 영향을 미치는 것으로 생각되며, 선체단면의 기하학적인 변형이 운동에 미치는 영향은 중요한 요소가 되질 못한다. 4) 감쇠력계수와 선체단면계수와의 관계는 간단한 관계를 유지한다.

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The Adsorption of Amines on Silicates. Distinction Protonic and Aprotonic Acids Sites (Silicate 上에서의 아민의 吸着. Protonic 酸 자리와 Aprotonic 酸 자리의 區別)

  • Kim Jong-Taik;Sohn Jong-Rack
    • Journal of the Korean Chemical Society
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    • v.20 no.6
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    • pp.441-447
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    • 1976
  • The infrared spectra obtained in the region of $4000∼1200 $cm^{-1}$ has been measured for pyridine, tertiary butylamine, and ethylenediamine adsorbed on various cation-exchanged silicates at various degassing temperature. It was possible to distinguish between protonic and aprotonic acid sites of all cation-exchanged silicates which exhibited both Bronsted and Lewis acidity. The sodium form appeared to be the least reactive towards adsorbates. The relative ratio of the band intensities of tertiary butylamine was directly related to the polarizing power of exchanged cations. Ethylenediamine was less easily desorbed from silicate surface than tertiary butylamine due to the additional amino group to react with surface active site, and probably to form ether hydrogen bond with surface oxgen by liberating migrating proton besides the coordination bond with Lewis acid site and the formation of$NH3^+$ species with Bronsted acid site.

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Added Mass for both Vertical and Horizontal Vibration of Two-Dimensional Cylinders of Curvilinear-Element Sections with Chines in a Free Surface (Chine형(型) 선체단면(船體斷面) 주상체(柱狀體)의 자유수면(自由水面)에서의 상하(上下) 및 수평진동(水平振動)에 대(對)한 부가질량(附加質量))

  • Keuck-Chun,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.6 no.1
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    • pp.1-24
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    • 1969
  • Added masses of two-dimensional cylinders of curvilinear-element sections with chines, which are similar to marked V character ship sections with either single or double chines, oscillating at high frequency in a free surface of an ideal fluid are calculated for both vertical and horizontal vibration by employing two particular two-parameter families of the conformal transformation. The numerical results are graphically presented in the forms of added mass coefficient curves in terms of the sectional area coefficient and the half beam-draft ratio together with the section contours derived with the employed transformations, and discussed in comparision with those of the Lewis forms and of straightline-element sections with single chine for vertical vibration, and, for horizontal vibration, with those of the Lewis forms.

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Hydrogen-bonded clusters in transformed Lewis acid to new Brønsted acid over WOx/SiO2 catalyst

  • Boonpai, Sirawat;Wannakao, Sippakorn;Panpranot, Joongjai;Praserthdam, Supareak;Chirawatkul, Prae;Praserthdam, Piyasan
    • Advances in nano research
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    • v.12 no.3
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    • pp.291-300
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    • 2022
  • The behavior of hydrogen species on the surface of the catalyst during the Lewis acid transformation to form Brønsted acid sites over the spherical silica-supported WOx catalyst was investigated. To understand the structure-activity relationship of Lewis acid transformation and hydrogen bonding interactions, we explore the potential of using the in situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS) with adsorbed ammonia and hydrogen exposure. From the results of in situ DRIFTS measurements, Lewis acid sites on surface catalysts were transformed into new Brønsted acid sites upon hydrogen exposure. The adsorbed NH3 on Lewis acid sites migrated to Brønsted acid sites forming NH4+. The results show that the dissociated H atoms present on the catalyst surface formed new Si-OH hydroxyl species - the new Brønsted acid site. Besides, the isolated Si-O-W species is the key towards H-bond and Si-OH formation. Additionally, the H atoms adsorbed surrounding the Si-O-W species of mono-oxo O=WO4 and di-oxo (O=)2WO2 species, where the Si-O-W species are the main species presented on the Inc-SSP catalysts than that of the IWI-SSP catalysts.

A Study on the Stream Lines Calculation around a Ship's Hull (선체주위(船體周圍)의 유선계산법(流線計算法)에 관(關)한 연구(硏究))

  • K.J.,Cho;S.W.,Hong;C.W.,Park
    • Bulletin of the Society of Naval Architects of Korea
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    • v.14 no.2
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    • pp.1-9
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    • 1977
  • Streamlines around a ship's hull can be calculated by using streamline tracing method replacing the ship section with distribution of singularity. The influence of frame lines on the stream surrounding a hull surface, however, can not be found. Jinnaka studied on streamlines for Lewis form by applying the slender body theory. The influence of frame lines on stream surrounding a hull surface is well found in Jinnaka's method. In this paper streamline calculation method for chine type has been developed by using conformal transformation and applying slender body theory as Jinnaka did. Three kinds of model-one of series 62 for chine type, V.L.C.C. and high speed craft built in Korea for Lewis form-were used for streamline calculation;

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On the Hydrodynamic Forces of Oscillating Cylinders in the Presence of a Free Surface

  • Hwang, J.H.;Rhee, K.P.;Hong, S.W.
    • Bulletin of the Society of Naval Architects of Korea
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    • v.17 no.4
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    • pp.13-20
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    • 1980
  • The integral equation method to solve the boundary-value problem of a 2-dimensional body oscillating in the presence of a free surface generally breaks down at and near irregular frequencies due to the hypothetical flow inside the body. In this paper singularity distributions were extended to an inner free surface to remove the irregular frequency as Ohmatsu's work in 1978, and the solution for the above problem was found by using stream function. For various bodies including Lewis form cylinders, the hydrodynamic forces were calculated numerically at various wave numbers. From the results we concluded that the irregular frequencies can be removed even for the Lewis form cylinder as Ohmatsu done for circular cylinders, and calculated hydrodynamic forces by the present method are little higher than those of Ohmatsu's when the singularities are put on the inner free surface of the body. We specially point out that the solution for heaving motion converges in an oscillatory manner but not for swaying and rolling motions.

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A Note on the Two-Dimensional Added Mass Moment of Inertia in Torsional Vibration of Cylinders of Curvilinear-Element Sections with Chines. (배골형단면(背骨型斷面) 주상체(柱狀體)의 자유수면(自由水面)하에서의 비틂진동(振動)에 대(對)한 이차원적(二次元的) 부가관성(附加慣性)모우먼트의 계산(計算))

  • Key-P.,Rhee;Y.S.,Yang
    • Bulletin of the Society of Naval Architects of Korea
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    • v.11 no.2
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    • pp.41-44
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    • 1974
  • A calculation of the two dimensional added mass moment of inertia for the Kim's chine form sections is made with a special consideration of a location of a axis of rotation. The results are compared with those of Lewis form section equivalent to the above chine form sections calculated by Kumai.

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