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Application of Multichannel Quantum Defect Theory to the Triatomic van der Waals Predissociation Process II

  • 이천우
    • Bulletin of the Korean Chemical Society
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    • v.16 no.10
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    • pp.957-968
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    • 1995
  • Generalized Multichannel Quantum Defect theory (MQDT) was implemented to the vibrational predissociation of triatomic van der Waals molecules in the previous paper [Bull. Korean Chem. Soc, 12, 228 (1991)]. Implementation was limited to the calculation of the scattering matrix. It is now extended to the calculation of the predissociation spectra and the final rotational distribution of the photofragment. The comparison of the results with those obtained by other methods, such as Golden-rule type calculation, infinite order sudden approximation (IOS), and close-coupling method, shows that the implementation is successful despite the fact that transition dipole moments show more energy dependence than other quantum defect parameters. Examination of the short-range channel basis functions shows that they resemble angle-like functions and provide the validity of the IOS approximation. Besides the validity of the latter, only a few angles are found to play the major role in photodissociation. In addition to the implementation of MQDT, more progress in MQDT itself is made and reported here.

Application of Multichannel Quantum Defect Theory to the Triatomic van der Waals Predissociation Process

  • Chun-Woo Lee
    • Bulletin of the Korean Chemical Society
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    • v.12 no.2
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    • pp.228-238
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    • 1991
  • Generalized multichannel quantum defect theory [C. H. Greene et al. Phys. Rev., A26, 2441 (1982)] is implemented to the vibrational predissociation of triatomic van der Waals molecules. As this is the first one of such an application, the dependences of the quantum defect parameters on energy and radius are examined carefully. Calculation shows that, in the physically important region, quantum defect parameters remain smoothly varying functions of energy for this system as in atomic applications, thus allowing us very coarse energy mesh calculations for the photodissociation spectra. The choice of adiabatic or diabatic potentials as reference potentials for the calculation of quantum defect parameters as done by Mies and Julienne [J. Chem. Phys., 80, 2526 (1984)] can not be used for this system. Physically motivated reference potentials that may be generally applicable to all kinds of systems are utilized instead. In principle, implementation can be done to any other predissociation processes with the same method.

X-X: Single-Crystalline Si TFTs Fabricated with ${\mu}-Czochralski$ (grain-filter) process

  • Ishihara, R.;Dijk, B.D.van;Wilt, P.Ch. van der;Metselaar, J.W.;Beenakker, C.I.M.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.159-162
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    • 2002
  • This paper reviews an advanced excimer-laser crystallization technique enabling precise location-control of the individual grains. With the developed ${\mu}$-Czochralski (grain-filter) process, the large grains having a diameter of 6 ${\mu}m$ can be set precisely at predetermined positions. We will also discuss the performance of the single-crystalline Si TFTs that are formed within the location-controlled Si grains. The field-effect mobility for electrons is 430 $cm^2/Vs$ on average, which is well comparable to that of TFTs made with silicon-on-insulator wafers.

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Multicenter Epidemiologic Study on Hepatocellular Carcinoma in Turkey

  • Can, Alper;Dogan, Erkan;Bayoglu, Ibrahim Vedat;Tatli, Ali Murat;Besiroglu, Mehmet;Kocer, Murat;Dulger, Ahmet Cumhur;Uyeturk, Ummugul;Kivrak, Derya;Orakci, Zuat;Bal, Oznur;Kacan, Turgut;Olmez, Sehmus;Turan, Nedim;Ozbay, Mehmet Fatih;Alacacioglu, Ahmet
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2923-2927
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    • 2014
  • Background: Hepatocellular cancer (HCC) is one of the important health problems in Turkey, being very common and highly lethal. The aim of this study was to determine clinical, demographic features and risk factors. Materials and Methods: Nine hundred and sixth-three patients with HCC from 13 cities in Turkey were included in this study. Results: Only 205 (21%) of the 963 patients were women, with a male:female predominance of 4.8:1 and a median age of 61 years. The etiologic risk factors for HCC were hepatitis B in 555 patients (57.6%), 453 (81%) in men, and 102 (19%) in women, again with male predominance, hepatitis C in 159 (16.5%), (14.9% and 22.4%, with a higher incidence in women), and chronic alcohol abuse (more than ten years) in 137 (14.2%) (16.8% and 4.9%, higher in males). The Child-Pugh score paralleled with advanced disease stage amd also a high level of AFP. Conclusions: According to our findings the viral etiology (hepatitis B and hepatitis C infections) in the Turkish population was the most important factor in HCC development, with alcohol abuse as the third risk factor. The Child-Pugh classification and AFP levels were determined to be important prognostic factors in HCC patients.

Experimental Study on the Unsaturated Characteristics of Dredging Soils at Saemangeum Area (새만금지역 준설토의 불포화 특성에 대한 실험적 연구)

  • Song, Young-Suk;You, Seung-Kyong
    • Journal of the Korean Geosynthetics Society
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    • v.10 no.3
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    • pp.25-32
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    • 2011
  • The matric suction and volumetric water content of dredging soils obtained from Saemangeum area were measured by the automated Soil-Water Characteristic Curve (SWCC) apparatus under both drying and wetting conditions. Based on the test result, SWCCs of the dredging soils were estimated by the van Genuchten(1980) model. The matric suction of drying process is larger than that of wetting process at a same effective degree of saturation. The suction stresses for various matirc suctions were estimated using Lu and Likos(2006) model and the Suction Stress Characteristic Curves (SSCC) were predicted using the independent parameter of SWCC. The suction stress of drying path was increased and decreased, while the suction stress of wetting path was continuously decreased with increasing the effective degree. Also, the suction stress of drying path is larger than that of wetting path at a same effective degree of saturation. The Hydraulic Conductivity Function(HCF) was also predicted by the van Genuchten(1980) model. The hydraulic conductivity was increased with increasing the volumetric water content. The hydraulic conductivity of drying path is larger than that of wetting path at a same matric suction. According to the results of SWCCs and SSCCs, the hysteresis phenomenon of suction stress or matric suction during both drying and wetting paths was occurred. The main reason of hysteresis phenomenon is a ink bottle effect of water among soil particles.

An Analysis of Justification Process in the Proofs by Mathematically Gifted Elementary Students (수학 영재 교육 대상 학생의 기하 인지 수준과 증명 정당화 특성 분석)

  • Kim, Ji-Young;Park, Man-Goo
    • Education of Primary School Mathematics
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    • v.14 no.1
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    • pp.13-26
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    • 2011
  • The purpose of this research is to analyze geometrical level and the justification process in the proofs of construction by mathematically gifted elementary students. Justification is one of crucial aspect in geometry learning. However, justification is considered as a difficult domain in geometry due to overemphasizing deductive justification. Therefore, researchers used construction with which the students could reveal their justification processes. We also investigated geometrical thought of the mathematically gifted students based on van Hieles's Theory. We analyzed intellectual of the justification process in geometric construction by the mathematically gifted students. 18 mathematically gifted students showed their justification processes when they were explaining their mathematical reasoning in construction. Also, students used the GSP program in some lessons and at home and tested students' geometric levels using the van Hieles's theory. However, we used pencil and paper worksheets for the analyses. The findings show that the levels of van Hieles's geometric thinking of the most gifted students were on from 2 to 3. In the process of justification, they used cut and paste strategies and also used concrete numbers and recalled the previous learning experience. Most of them did not show original ideas of justification during their proofs. We need to use a more sophisticative tasks and approaches so that we can lead gifted students to produce a more creative thinking.

The Range of Physicochemical Parameters for the Active Ingredients of Fungicides and Insecticides as Crop Protection Agents (작물 보호제로서 살균제와 살충제의 활성 성분에 대한 물리-화학 파라미터의 범위)

  • Song, Sun-Sup;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.46 no.4
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    • pp.280-284
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    • 2003
  • To develope of diagnosis and estimation system for utility of fungicides and insecticides as crop protection agents, various 10 physicochemical parameters, hydrophobicity (LogP), dipole moment (DM), HOMO energy, LUMO energy, molar refractivity $(MR:\;cm^3/mol)$, polarizability $(Pol:\;A^3)$, van der Waals molecular surface area $(A^2)$, van der Waals molecular volume $(Vol:\;cm^3)$, molecular weight (amu), hydration energy (Kcal/mol) for the active ingredients of 133 fungicides and 152 insecticides were calculated. And then the distribution ranges for each of the physicochemical parameters in fungicides, sterol biosynthesis inhibitors (DMI: demethylation inhibitor), insecticides and acetylcholine esterase inhibitors (AChE) were confirmed. It is suggested that the various compounds based on the range of the physicochemical parametes could be predicted for possibilities as fungicides and insecticides.

Prediction of Retention Behavior of Alkyl Benzenes by Hydrophobicity Parameters in Reversed-Phase Column (소수성 파라메터를 적용한 알킬벤젠류의 역상컬럼내의 용출거동 예측)

  • Lee, Chang-Young;Park, Myung-Yong;Lee, Yong-Moon
    • YAKHAK HOEJI
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    • v.53 no.5
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    • pp.281-285
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    • 2009
  • The retention of solutes in reversed-phase high-performance liquid chromatography depends on their hydrophobicity. Although the retention behaviors of alkyl benzenes have been reported so far, quite a few authors have mentioned the retention behavior of alkyl benzenes with plural hydrophobicity parameters. In this sense, we were interested in the retention behaviors of alkyl benzenes having benzene moiety and increasing alkyl chain. In this study, we therefore investigated the retention behavior of alkyl benzenes in reversed-phase high-performance liquid chromatography in order to obtain information concerning the effects of the aromatic moiety and the carbon chain on the retention mechanism by comparing their capacity factor (k') in relation to the carbon chain length. The eluent acetonitrile ($CH_3CN$) showed high selectivity on alkyl benzenes, showing the high difference of capacity factor (${\Delta}log\;k'$) between toluene and octyl benzene. Indeed, the ${\Delta}log\;k'$ of 80% $CH_3CN$ represented 1.42- and 4.25-times longer than 90% MeOH and 60% THF, respectively. The hydrophobicity parameters, van der Waals volume, bond constant, partition constant, $\pi$-energy effect and enthalpy were evaluated with the capacity factor (k') of alkyl benzenes eluted on 80% CH3CN, 90% MeOH and 60% THF, respectively. The best eluent for predicting retention behavior of alkyl benzenes was 90% MeOH ($R^2$ 0.999). The three parameters, van der Waals volume, bond constant and partition constant were well coincident to log k' by increasing alkyl benzenes. However, $\pi$-energy effect and enthalpy were severely disagreeable. Taken together, van der Waals volume, bond constant and partition constant were a reliable parameters to predict the retention behaviors of alkyl benzenes on reversed-phase column.

Damages of minarets during Erciş and Edremit Earthquakes, 2011 in Turkey

  • Bayraktar, Alemdar;Altunisik, Ahmet Can;Muvafik, Murat
    • Smart Structures and Systems
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    • v.14 no.3
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    • pp.479-499
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    • 2014
  • This paper illustrates the damages of reinforced concrete and masonry minarets during October 23 (Erciş) and November 9 (Edremit), 2011 Van earthquakes in Turkey. Erciş and Edremit are townships located 90km and 18km from Van city center in Turkey, respectively. Ground accelerations and response spectrums for these earthquakes are given in this paper. A total of 63 reinforced concrete and masonry minarets are heavily damaged or collapsed in the city center and villages nearby after both earthquakes. Because of the fact that there is no Turkish standard and specification directly related to design of minarets, nearly all of the constructions are carried out by workers using only their own technical knowledge. So, all of the non-engineering reinforced concrete and masonry minarets completely collapsed or damaged heavily. From the study, it is seen that the damages are due to several reasons such as site effect, location, and length of the fault, reduction in cross section and formation of the discontinuity, use of plain reinforcement steel, use of concrete with insufficient strength, existence of short lap splices and incorrect end hook angle, larger mass and stiffness concentrations on some region, longitudinal reinforcements discontinuity, cracks at the cylindrical body, and damage of spire and end ornament. In addition to these reasons, the two earthquakes hit the minarets within seventeen days, causing progressive damage. So, the existing design and construction practices should be improved to provide sufficient earthquake performance. Also, it is recommended that there should be a safe distance between the minaret and surrounding structures to reduce the loose of life after earthquake.

Edge Based Dynamic Brush Stroke Generation for Painterly Rendering (회화적 렌더링을 위한 에지 기반 동적 브러시 스트로크 생성에 관한 연구)

  • Park Youngsup;Yoon Kyunghyun
    • Journal of Korea Multimedia Society
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    • v.8 no.2
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    • pp.164-173
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    • 2005
  • Painterly rendering may bring various results through the parameters that determine the characteristics of brush strokes such as, color, orientation, size, and shape. In this paper, we propose the most adaptive brush stroke generation for source images, using reference data. Our algorithm used Colors formed by actual palette colors from artists. To create the palette, we have referred mostly to colors used in Van Gogh's works and determined the color of brush strokes by transferring it to the most similar one, through comparing colors used in source images and the palette colors. Also, In order to emulate a brush stroke with dynamic properties like Van Gogh styles we have applied a brush stroke orientation that surrounds the edges by referring to the edge orientation of source images. The sizes were determined depending on the different sizes of the objects from wide to narrow brushes. Finally, we applied spline curve shapes to simulate curves and swirls like Van Gogh styles. The brush strokes created in such method, were applied separately according to its segmented images, and composed after rendering.

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