• Title/Summary/Keyword: p-basis

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Studies on the Dissociation Constant of Benzoic Acid and Substituted Benzoic Acids in Methanol-Water Mixtures by Conductometric Method (메탄올-물 혼합용매에서 전도도법에 의한 벤조산 및 치환된 벤조산의 해리에 관한 연구)

  • Min Soo Cho;Hyoung Ryun Park;Soon Ki Rhee;Kye Soo Lee;Bon Su Lee
    • Journal of the Korean Chemical Society
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    • v.35 no.3
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    • pp.196-203
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    • 1991
  • The $pK_a$ values of benzoic acid and meta, para-halogen substituted benzoic acids in MeOH-$H_2O$ mixtures (0∼80% of MeOH) have been determined at 25$^{\circ}$C using a conductometric method on the basis of the Fuoss-Kraus equation, and further verified using modified conductometric method of Gelb. The dependence of $pK_a$ on halogen substituents has been discussed in terms of substituent-constant (${\sigma}$), which is devided into electron-withdrawing inductive contribution (${\sigma}_1$) and electron-donating ${\pi}$-resonance one (${\sigma}_R$). The linear-dependence of ${\sigma}_1$'s on $D^{-1}$ with positive slope and that of ${\sigma}_R$'s on $D^{-1}$ with negative slope have been interpreted on the basis of field effect and through-space interaction of ${\pi}$-lone pair of halogen substituent and ionization center via ${\pi}$-system of benzene ring.

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Theoretical Study for Thermally Activated Delayed Fluorescence (TADF) Property in Organic Light-Emitting Diode (OLED) Candidates (유기발광소재(OLED) 후보물질의 지연형광(TADF) 성질에 대한 이론적 연구)

  • Seo, Hyun-il;Jeong, Hyeon Jin;Yoon, Byung Jin;Kim, Seung-Joon
    • Journal of the Korean Chemical Society
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    • v.63 no.3
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    • pp.151-159
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    • 2019
  • The TADF properties for carbazol-dicyanobenzene, carbazol-diphenyl sulfone, carbazol-benzonitrile derivatives as OLED candidate materials are theoretically investigated using density functional theory (DFT) with $6-31G^{**}$, cc-pVDZ, and cc-pVTZ basis sets. The optimized geometries, harmonic vibrational frequencies, and HOMO-LUMO energy separations are predicted at the B3LYP/$6-31G^{**}$ level of theory. The harmonic vibrational frequencies of the molecules considered in this study show all real numbers implying true minima. The time dependent density functional theory (TD-DFT) calculations have been also applied to investigate the absorption and emission wavelength (${\lambda}_{max}$), energy differences (${\Delta}E_{ST}$) between excited singlet ($S_1$) and triplet ($T_1$) states of candidate materials.

Differences in mandibular condyle and glenoid fossa morphology in relation to vertical and sagittal skeletal patterns: A cone-beam computed tomography study

  • Noh, Kyoung Jin;Baik, Hyoung-Seon;Han, Sang-Sun;Jang, Woowon;Choi, Yoon Jeong
    • The korean journal of orthodontics
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    • v.51 no.2
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    • pp.126-134
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    • 2021
  • Objective: This study aimed to evaluate the following null hypothesis: there are no differences in the morphology of the temporomandibular joint (TMJ) structures in relation to vertical and sagittal cephalometric patterns. Methods: This retrospective study was performed with 131 participants showing no TMJ symptoms. The participants were divided into Class I, II, and III groups on the basis of their sagittal cephalometric relationships and into hyperdivergent, normodivergent, and hypodivergent groups on the basis of their vertical cephalometric relationships. The following measurements were performed using cone-beam computed tomography images and compared among the groups: condylar volume, condylar size (width, length, and height), fossa size (length and height), and condyle-to-fossa joint spaces at the anterior, superior, and posterior condylar poles. Results: The null hypothesis was rejected. The Class III group showed larger values for condylar width, condylar height, and fossa height than the Class II group (p < 0.05). Condylar volume and superior joint space in the hyperdivergent group were significantly smaller than those in the other two vertical groups (p < 0.001), whereas fossa length and height were significantly larger in the hyperdivergent group than in the other groups (p < 0.01). The hypodivergent group showed a greater condylar width than the hyperdivergent group (p < 0.01). The sagittal and vertical cephalometric patterns showed statistically significant interactions for fossa length and height. Conclusions: TMJ morphology differed across diverse skeletal cephalometric patterns. The fossa length and height were affected by the interactions of the vertical and sagittal skeletal patterns.

Effective Management of Personal Information & Information Security Management System(ISMS-P) Authentication systems (정보보호 및 개인정보보호 관리체계(ISMS-P) 인증제도의 효과적인 운영방안)

  • Hong, Sung Wook;Park, Jae-Pyo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.1
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    • pp.634-640
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    • 2020
  • The information security management system (ISMS) and the personal information management system (PIMS) have been integrated into a personal information & information security management system (ISMS-P) certification scheme in response to requests to reduce the time and cost to prepare certification schemes. Integration of the certification system has made it possible for the system operator to gain the advantage of easy management of the ISMS-P certification system, and the certification target organization can enjoy the advantage of easy acquisition and maintenance of certification. However, ambiguity in the application criteria of the target organization, and ambiguity in the certification criteria control items require the target organization to operate an excessive management system, and the legal basis to be applied to the certification target organization is ambiguous. In order to improve these problems, this paper uses case studies to identify the types of certification bodies that apply the certification criteria, and to change the control items applied during certification audits based on the types of certification bodies. Institutions that wish to obtain only ISMS certification have proposed three solutions, excluding controls covered by the ISMS-P. This paper suggests ways to operate an efficient certification system, and can be used as a basis for improving problems in the ISMS-P certification system.

Ab Initio Quantum Mechanical Studies of 1,2-, 1,3-Dioxetanes and 1,3-Cyclodisiloxane; Energetics, Molecular Structures, Vibrational Frequencies (1,2-, 1,3-dioxetanes, 그리고 1,3-cyclodisiloxane의 분자구조, 에너지와 진동주파수에 대한 순 이론 양자 역학적 연구)

  • Choi Kun-Sik Choi;Seung-Joon Kim
    • Journal of the Korean Chemical Society
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    • v.47 no.4
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    • pp.325-333
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    • 2003
  • The geometrical parameters, vibrational frequencies, and relative energies for 1,2-, 1,3-dioxetanes, and 1,3-cyclodisiloxane have been investigated using high level ab initio quantum mechanical techniques with large basis sets. The geometries have been optimized at the self-consistent field(SCF), the single and double excitation configuration interaction(CISD), the coupled cluster with single and double excitation(CCSD), and the CCSD with connected triple excitations[CCSD(T)] levels of theory. The highest level of theory employed in this study is TZ2P CCSD(T). Harmonic vibrational frequencies and IR intensities are also determined at the SCF level of theory with various basis sets and confirm that all the optimized geometries are true minima. Also zero-point vibrational energies have been considered to predict the dimerization energies for 1,2- and 1,3-isomers.

Grains and Roughage Production and Its Utilization in Asian-Australasian Region - Review -

  • Bhat, P.N.;Bansil, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.3
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    • pp.481-492
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    • 1999
  • Asian-Australasian region comprises of 82 countries spread over varying agro economic zones, habitats and ecosystems varying from dry hot to humid tropics and cold deserts. The literacy standards vary from very low to almost 100 percent. On the basis of economic development there are 4 countries Japan, Australia, New Zealand and Korea which are developed countries, rest are in varying states of development and growing economically very rapidly. Based on Agro ecosystems and farming practices, we have chosen four countries for indepth study in this paper namely China, Thailand, Indonesia and India. They represent 70% of the bovine and poultry population of the region. This paper makes a comparative study of the grain and roughage production and utilization at present and in 2000 A.D. by examining information on feed rates demand patterns and feed requirements in these four countries keeping in view the size and growth of bovine and poultry population and dietary pattern of the people. It has been observed, there has so far been no country level detailed study on the livestock feed requirements. Apart from conceptual discrepancies, most of the estimates given in various reports brought out by the national governments and international agencies do not have any scientific basis. Hence an inter-country comparison is virtually impossible on the basis of the available information. We have however, attempted to analyse the dietary pattern in the different countries, feedgrains requirements, availability of feed based on the information available from the various published and unpublished reports. We have given an inter-country comparison of feed rate and feed requirements which, however, needs to be tested by carrying out a micro level study in each selected country.

The effects of makeup service marketing mix on customer revisit intention - Analysis of mediating effects of customer satisfaction and customer loyalty - (메이크업 서비스 마케팅 믹스가 고객재방문 의도에 미치는 영향 - 고객만족도와 고객충성도의 매개효과 분석 -)

  • Kang, Ji-Yeon
    • The Research Journal of the Costume Culture
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    • v.29 no.1
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    • pp.87-102
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    • 2021
  • The purpose of this study is to investigate customer satisfaction factors that affect customer loyalty and revisit intention, and the seven factors which comprise the marketing mix that affects customer satisfaction. loyalty, and intention to revisit. The purpose of the project is to propose a research model by testing the mediated effects of customer satisfaction and loyalty using mainly factor analysis, regression analysis, and mediation analysis. First the results showed that the marketing mix 7P factors influence customer satisfaction were identified as service delivery process, product, physical basis, and promotion. The factors that influence marketing mix 7P customer loyalty were tested in the order of service delivery, physical basis, product, and distribution. Second, the factors that affect customer loyalty were artists, service, and prices whereas the factors that affect customer satisfaction were tested in the order of service, artist, cosmetics, and price. Third, the factors affecting customer revisit intention were newly derived as treatment satisfaction, professionalism, and treatment products. Fourth, the relationship between marketing mix and customer revisit intention suggested that customer satisfaction and customer loyalty has a partial sale effect. It can be suggested on the basis of these findings that the effect of makeup service with marketing mix on customer revisit intention was analyzed and a new model was derived by analyzing the mediated effect of customer satisfaction and customer loyalty.

The Study of Optimal Conditions for Synthesis and Purification of 1, 2-Octanediol Galactoside (1, 2-Octanediol Galactoside 합성을 위한 최적 조건 및 정제 연구)

  • Jung, Kyung-Hwan
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.1
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    • pp.1-9
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    • 2022
  • 1, 2-Octanediol (OD) as a cosmetic additive has been used simultaneously as a preservative and humectant. To solve the skin problem by 1, 2-octanediol (OD), we have synthesized 1, 2-octanediol galactoside (OD-gal) using Escherichia coli β-galactosidase (β-gal). Meanwhile, the optimal amount of β-gal, OD concentration, pH, and temperature for OD-gal synthesis were 4.5 U/ml, 150 mM, 7.0, and 37℃, respectively. Under these conditions, 150 mM OD was converted into about 55.9 mM OD-gal during 24 hours, in which the conversion yield (mole basis) was about 37.2%. In addition, OD-gal of 67.4 mg could be purified from a 9 ml reaction mixture, in which the overall synthesis yield from OD to the purified OD-gal was about 34.1% (weight basis) and 16.2% (mole basis), respectively. We are expecting that these results will be helpful to develop a safer additive in the cosmetic industry as basic data.

A Study on the Analysis of Location Potential of Commercial Use using GIS Database (GIS DB를 이용한 상업·업무시설의 입지 포텐셜 분석)

  • Baek, Tae-Kyung;Choi, Jung-Mi
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.1
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    • pp.149-157
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    • 2006
  • The purpose of this study is to search for location potential in Busan metropolitan city and to support decision-making in land use policy. As basis work for the analysis of the location potential, we build rank-map database by using the 11 index. And then by using rank-map, we carried out the location potential ($P_i$) analysis. As a result, we found that many commercial use located in Rank 1 to 2. Also, Rank 4-7 must be made an un-commercial use in assignment of land use zone. These data can be effectively used for land use plan in Busan metropolitan city as the basis data.

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Inhibition of the Induction of Nitric Oxide Synthase by Kobusin

  • Kim, Sang-Kyum;Pokharel, Yuba-Raj;Kim, Ok;Woo, Eun-Rhan;Kang, Keon-Wook
    • Toxicological Research
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    • v.23 no.2
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    • pp.123-126
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    • 2007
  • We isolated a lignan, kobusin from Geranium thunbergii and studied its effect on the expression of inducible nitric oxide synthase (iNOS) gene in a monocyte/macrophage cell line, RAW264.7 cells. Kobusin inhibited lipopolysaccharide (LPS)-stimulated NO production and the expression of iNOS in a concentration-dependent manner. To identify the mechanistic basis for its inhibition of iNOS induction, we examined the effect of kobusin on both the luciferase reporter activity using $NF-{\kappa}B$ minimal promoter and the nuclear translocation of p65. Kobusin suppressed the reporter gene activity and the LPS-induced movement of p65 in to nucleus. $NF-{\kappa}B$ activation is controlled by the phosphorylation and subsequent degradation of $I-{\kappa}B{\alpha}$, and in the present study, we found that $I-{\kappa}B{\alpha}$ phosphorylation was also inhibited by kobusin. Our findings indicate that kobusin may provide a developmental basis for an agent against inflammatory diseases.