• Journal of the Korean Chemical Society
• /
• v.25 no.3
• /
• pp.152-159
• /
• 1981

The rates of solvolysis for p-nitrobenzyl chloride have been measured by the electric conductivity method in aqueous ethanol from 0.0 to 0. 5 mole fraction of ethanol under various pressures up to 1200bar at 50 and $60{\circ}C$. The activation parameters, ${\Delta}V_\0^{\neq},\ {\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ are evaluated from the rate constants. The results indicated that ${\Delta}V_\0^{\neq}$ exhibits an extremum behaviors near 0.3 mole fraction of ethanol and ${\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ near 0.1 mole fraction of ethanol. This behaviors are discussed in terms of solvent structure variation and the pressure dependences of ${\Delta}H^{\neq},\ {\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ are also discussed individually. The signs of the pressure dependence of ${\Delta}H^{\neq}$${\Delta}S^{\neq}$ are shown to be consistent with those required by the Maxwell relationships for classical thermodynamic systems.

• Journal of the Korean Chemical Society
• /
• v.24 no.2
• /
• pp.108-114
• /
• 1980

By using electrostatic model and simple bond additivity scheme a reasonable and simple method was developed for the estimation of standard enthalpy of formation $({\Delta}H_f\;^{\circ})$ of very polar compounds. The bond contributions to the enthalpy of formation for halomethanes were; ${\Delta}H_f\;^{\circ}(C-F)=-36.44\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-Cl)=-2.57\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-Br)=5.32\;kcal/mole,\;{\Delta}H_f\;^{\circ}(C-I)=19.18\;kcal/mole,\;and\;{\Delta}H_f\;^{\circ}(C-H)=-3.61\;kcal/mole$, respectively. Using these values and calculated electrostatic energies, the estimated ${\Delta}H_f\;^{\circ}$ values were estimated and found to be in good agreement with observed values.

• Kyungpook Mathematical Journal
• /
• v.11 no.1
• /
• pp.93-99
• /
• 1971

In this paper, the author has established the formulae for product of two generalized hypergeometric polynomials by defining the polynomial in the form $$F_n(x)=x^{({\delta}-1)n}{_{p+{\delta}}F_q}\[\array{{\Delta}({\delta},-n),&a_1,&{\cdots}{\cdots},&a_p\\&b_1,&{\cdots}{\cdots},&b_q};\;{\lambda}x^c\]$$, where the symbol ${\Delta}({\delta},-n)$ represents the set of ${\delta}$-parameters: $${\frac{-n}{\delta}},\;{\frac{-n+1}{\delta}},\;{\cdots}{\cdots},\;{\frac{-n+{\delta}-1}{\delta}}$$ and ${\delta}$, n are positive integers. A number of known as well as new results have been also obtained with proper choice of parameters.

• 월간 기계설비
• /
• no.10 s.207
• /
• pp.64-70
• /
• 2007

점차 지능화.조직화되고 있는 고용보험 지원금의 부정수급 방지를 위해 건설고용보험카드를 단계적으로 확대하고 4대 사회보험 및 국세청 신고자료의 연계를 확대하는 등 종합대책이 마련됐다. 노동부는 실업급여를 포함한 고용보험 각종 지원금의 부정수급을 근원적으로 방지하고 고용보험제도의 효과적 운영을 위해 '부정수급 자동경보시스템'을 구축하고 각종 제도와 절차 등을 개선하는 내용의 '고용보험사업 내실화 및 부정수급 방지 종합대책'을 수립, 시행한다고 밝혔다. 이번 종합대책은 $\Delta$부정수급 사전예방 강화 $\Delta$효과적인 적발 시스템 구축 $\Delta$제재조치의 강화 $\Delta$부정수급 관리역량 확충 등이다. 종합대책의 주요 내용은 $\Delta$건설고용보험카드 단계적 확대 $\Delta$피보험자 소득취득 관리강화 $\Delta$4대사회보험 및 국세청 신고자료 연계확대 $\Delta$직업소개 거부시 구직급여 감액제도 도입 $\Delta$훈련기관 지문인식 출결관리 시스템 확대 $\Delta$부정수급 자동경보 시스템 구축 $\Delta$제보자에 대한 포상금 인상(부정수급액의 $10%\rightarrow 20%$) $\Delta$과태료 신설 등이다.

• Journal of the Korean Chemical Society
• /
• v.38 no.2
• /
• pp.108-121
• /
• 1994

The retention indices of branched-chain alkane, benzene ring, alcohol, amine, ketone, aldehyde and cyclic compounds were measured at 150, 180 and $210^{\circ}C$ on OV-1701 and OV-1 capillary columns. The group retention factors (GRF) of the substituents and the st` ructure retention factors (SRF) of the molecular structure change are derived from the retention indices of reference compounds and series of homologues. The $GRF_f$ equation of `f'th substituent is $GRF_f\;=\;I_{obs}-(100Z + \sum\limits_{i{\neq}f}GRF_i$ + {\sum}$SRF_i$)and the SRFf equation of `f'th molecular structure group is $SRF_f\;=\;I_{obs}-(100Z + {\sum}GRFi + \sum\limits_{i{\neq}f}SRF_i$). The predicted retention indices for those compound were in agreement, within the error of $\pm2$ and $\pm3%$, with the observed values that were obtained using the OV-1701 and OV-1 capillary column, respectively. The $\Delta$ xi of the substituents and $\Delta$ yi of the molecular structure change according to temperature change are derived from the $\Delta'/^{\circ}C$ of reference compounds and series of homologues. The $\Delta$ xi equation of the `f'th substituent is ${\Delta}x_f = {$\Delta}'/^{\circ}C+ \sum\limits_{i{\neq}f}\Delta$ xi + {\sum}{\Delta}yi\;and\;{\Delta}yi$ equation of the `f'th molecular structure group is ${\Delta}y_f$ = {\Delta}'/^{\circ}C+{\sum}{\Delta}xi +\sum\limits_{i{\neq}f}{\Delta}yi$. The predicted $\Delta'/^{\circ}C$ for these compounds were in agreement, within the error of ${\pm}18%$ and 17%, with the observed values that were obtained using the OV-1701 and OV-1 capillary column, respectively.

• Journal of the Korean Mathematical Society
• /
• v.55 no.6
• /
• pp.1381-1388
• /
• 2018

Let ${\Delta}$ be a simplicial complex, $I_{\Delta}$ its Stanley-Reisner ideal and $K[{\Delta}]$ its Stanley-Reisner ring over a field K. Assume that ${\Gamma}(R)$ denotes the zero-divisor graph of a commutative ring R. Here, first we present a condition on two reduced Noetherian rings R and R', equivalent to ${\Gamma}(R){\cong}{\Gamma}(R{^{\prime}})$. In particular, we show that ${\Gamma}(K[{\Delta}]){\cong}{\Gamma}(K^{\prime}[{\Delta}^{\prime}])$ if and only if ${\mid}Ass(I_{\Delta}){\mid}={\mid}Ass(I_{{{\Delta}^{\prime}}}){\mid}$ and either ${\mid}K{\mid}$, ${\mid}K^{\prime}{\mid}{\leq}{\aleph}_0$ or ${\mid}K{\mid}={\mid}K^{\prime}{\mid}$. This shows that ${\Gamma}(K[{\Delta}])$ contains little information about $K[{\Delta}]$. Then, we define the squarefree zero-divisor graph of $K[{\Delta}]$, denoted by ${\Gamma}_{sf}(K[{\Delta}])$, and prove that ${\Gamma}_{sf}(K[{\Delta}){\cong}{\Gamma}_{sf}(K[{\Delta}^{\prime}])$ if and only if $K[{\Delta}]{\cong}K[{\Delta}^{\prime}]$. Moreover, we show how to find dim $K[{\Delta}]$ and ${\mid}Ass(K[{\Delta}]){\mid}$ from ${\Gamma}_{sf}(K[{\Delta}])$.

• Honam Mathematical Journal
• /
• v.39 no.4
• /
• pp.527-559
• /
• 2017

The main motivation of this article is to generalized the concept of fuzzy ideals, (${\alpha},{\beta}$)-fuzzy ideals, (${\in},{\in}{\vee}q_k$)-fuzzy ideals of semigroups. By using the concept of $q^{\delta}_K$-quasi-coincident of a fuzzy point with a fuzzy set, we introduce the notions of (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy left ideal, (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy right ideal of a semigroup. Special sets, so called $Q^{\delta}_k$-set and $[{\lambda}^{\delta}_k]_t$-set, condition for the $Q^{\delta}_k$-set and $[{\lambda}^{\delta}_k]_t$-set-set to be left (resp. right) ideals are considered. We finally characterize different classes of semigroups (regular, left weakly regular, right weakly regular) in term of (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy left ideal, (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy right ideal and (${\in},{\in}{\vee}q^{\delta}_k$)-fuzzy ideal of semigroup S.

• The Korean Journal of Ecology
• /
• v.4 no.3_4
• /
• pp.59-67
• /
• 1981

Stomatal resistances of the leaves in Heteromeres arbutifolia and of the stems in Ferocactus acanthodes were studied to estimate active and passive behaviors of the guard cells on a theoretical basis. Active and passive stomatal responses to light and water deficit were observed. When the change rate of existent water due to variation of osmotic potential in the guard cells and the loss rate of transpirational water from the guard cells are $\Delta$wi-$\Delta$wt and leaded to active behaviors for opening and closing stomata. However, when stems of F. acanthodes with stomata closecd under the solar irradiation were covered with black cloth and then taken off, behaviors of the guard cells occurred in the condition of $\Delta$wi<$\Delta$wt and were passive. Under the conditiion of $\Delta$wi<$\Delta$wt due to cutout from stems, passive behaviors of the guard cells in H. arbutifolia and F. acanthodes always occurred in spite of the solar irradiation and darkness, respectively. The transpirational resistance coefficients of the guard cells in stems of F. acanthodes (0.380) and Opuntia bigelovii (0.135) wer emuch higher than in leaves of H. arbutifolia (0.034). Moreover, stomatal opening in stems of F. acanthodes during the daytime could be induced by watering. Those results are interpreted as that since the guard cells in desert Crassulacean acid metabolism (CAM) plants always exist in the state of stomatal opening, nocturnal stomatal opening and daytime stomatal closing are exhibited by passive behaviors of the guard cells in the alternant conditioins of $\Delta$wi>$\Delta$wt and $\Delta$wi<$\Delta$wt, respectively.

• Journal of The Korean Astronomical Society
• /
• v.7 no.1
• /
• pp.1-10
• /
• 1974

The position and magnitude of 1449 stars listed in "Seoung Kyung" (by Byung Kil Nahm, 1861) are compared with those in modern western star catalogues for their identification. 923 stars out of 1449 stars were identified within the range of accuracy. ${\Delta}{\alpha}{\leq}20^s.0,\;{\Delta}{\delta}{\leq}1'.0\;and\;{\Delta}m=0\;or\;{\pm}1$. When ${\Delta}{\alpha}\;and\;{\Delta}{\delta}$ increased to ${\Delta}{\alpha}{\leq}1^m.\;0,\;{\Delta}{\delta}{\leq}15'.0\;and\;{\Delta}m=0$ or +1, 399 more stars could be included in the list.

• Journal of applied mathematics & informatics
• /
• v.23 no.1_2
• /
• pp.321-327
• /
• 2007

We say that a triangle ${\Delta}$ tiles the polygon ${\rho}\;if\;{\rho}$ can be decomposed into finitely many non-overlapping triangles similar to ${\Delta}$. Let ${\rho}$ be a parallelogram with angles ${\delta}\;and\;{\pi}-{\delta}\;(0<{\delta}{\leq}{\pi}/2)$ and let ${\Delta}$ be a triangle with angles ${\alpha};{\beta},\;{\gamma}\;({\alpha}{\leq}{\beta}{\leq}{\gamma})$. We prove that if ${\Delta}$ tiles ${\rho}$ then either ${\delta}{\in}\;({\alpha},\;{\beta},\;{\gamma},\;{\pi}-{\gamma},\;{\pi}-2{\gamma})\;or\;dimL_{\rho}=dimL_{{\Delta}}$. We also prove that for every parallelogram P, and for every integer n $(where\;n{\geq}2,\;n{\neq}3)$ there is a triangle ${\Delta}$ so that n similar copies of ${\Delta}\;tile\;{\rho}$.