• 한국가스학회:학술대회논문집
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• 2000.09a
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• pp.215-220
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• 2000

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.1963-1964
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• 2006

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.91-95
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• 1985

The dynamic properties near (and at) a stable steady state are discussed, when a chemical system relaxes from the unstable steady state. The time-dependent correlation length for the fluctuating variable near a stable steady state is explicitly obtained by introducing the probability average for the variable satisfying the rate equation. The study is carried out about the effect of nonlinearity on the correlation length near (and at) a stable steady state.

• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.566-574
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• 2021

This research was carried out to investigate the correlation between soil chemical properties and bioactive compounds of Acer tegmentosum Maxim. The methods of determining bioactive compounds were determined by high performance liquid chromatography, that contained (-)-gallocatechin (0.04±0.01 ~ 0.43±0.28%), salidroside (0.90±0.06 ~ 3.86±0.59%), tyrosol (0.03±0.00 ~ 0.43±0.00%), (-)-catechin (0.05±0.01 ~ 0.37±0.14%), 6'-O-galloylsalidroside (0.02± 0.01 ~ 0.31±0.06%), (-)-epicatechin-gallate (0.01±0.00 ~ 0.04±0.01%). The soil chemical properties analysis such as soil pH, electric conductivity (EC), organic matter (OM), total nitrogen (TN), available phosphate (Avail. P₂O₅), exchangeable cation and cation exchange capacity (CEC) were performed following the standard manual. The correlation analysis between soil chemical properties and bioactive compounds of A. tegmentosum, soil pH, available phosphate and exchangeable cation (Ca²⁺ and Mg²⁺) were negatively correlated with content of salidroside. On the other hand, soil exchangeable cation (Na⁺) showed positive correlation with content of salidroside. The results of this study was able to investigate the correlation between soil chemical properties and bioactive compounds of A. tegmentosum.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2351-2354
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• 2009

A series of N-arylsuccinanilic acids, N-arylsuccinimides, N-arylmaleanilic acids, and N-arylmaleimides was prepared and their NMR spectra were examined by correlating the $^1H\;and\;^{13}C$ chemical shift values with the corresponding Hammett $\sigma$ values. The carbonyl carbons of the amides show a normal correlation with $\sigma$ but those of the imides show an inverse correlation.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1689-1694
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• 2010

Substituent chemical shifts were examined for the 2- and 3-thiophene derivatives of chalcone and compared to the thiophene series of derivatives with the phenyl series. The chemical shift values for the ${\alpha}$-carbons of the enones showed and inverse correlation with the Hammett $\sigma$ values, but the correlation coefficients were moderate (r = 0.836 - 0.878). On the other hand, the $\beta$-carbons showed a normal correlation with excellent correlation coefficients (r = 0.994). The absolute magnitude of the $\rho$ values for the $\alpha$-carbon are about half of those of the $\beta$-carbon. The observation may be the result of a through-space transition of the electronic effect of the substituents in addition to the through bond transition.

• Journal of the Korean Chemical Society
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• v.67 no.1
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• pp.64-67
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• 2023

• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.438-449
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• 2020

This study is to improve the method of calculating the risk of liability that arise from release and dispersion of chemicals outside the plant in process industries such as chemical and petrochemical plants. To achieve this goal, the correlation factors with the risk of chemical release accident is derived by simulating release and dispersion of substances (14 types) designated by Ministry of Environment as preparation for accident, analyzing the cases of chemical release and effects of plant life damage. The method of calculating chemical liability risk was modified and supplemented based on the results obtained from the study. The correlation coefficient between the probit value of 14 chemical types and the liability risk by EURAM (European Union Risk Ranking Method) was -0.526, while the correlation coefficient with the modified chemical release accident risk was 0.319. Thus, the value from modified method shows that they appear to be correlated. According to modified calculating methodology, the correlation between ERPG-2 value and liability risk of 97 chemical types was -0.494 which is 19 times higher than existing liability risk correlation as absolute value. And the correlation coefficient of corrosion risk was 0.91. The standardized regression coefficients (β) value of correlation factors that affected the increase and decrease of risk were derived in order of Corrosion Index(0.713), ERPG-2 (0.400) and NFPA Health Index (0.0680) by values. It is expected that these findings this study result will also enable the calculation of reasonable chemical release liability risk for existing and new chemical, and will help use them as quantitative liability risk management indicators for chemical plant site.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1265-1268
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• 2003

The estimation of retention factors by correlation equations with physico-chmical properties maybe helpful in chromatographic work. The physico-chemical properties were water solubility (S), hydrophobicity (P), total energy ($E_t$), connectivity index 1 ($^1{\chi}$), hydrophilic-lipophlic balance (x) and hydrophilic surface area (h) of isoflavones. The retention factors were experimentally measured by RP-HPLC. Especially, the empirical regulations of water solubility and hydrophobicity were expressed in a linear form. The equation between retention factors and various physico-chemical properties of isoflavones was suggested as $k = a_0 + a_1\;log S + a_2log\;P^Q + a_3(E_t) + a_4(^1{\chi}) + a_5(x) + a_6(h)$, and the correlation coefficients estimated were relatively higher than 0.95. The empirical equations might be successfully used for a prediction of the various chromatographic characteristics of substances, with a similar chemical structure.

• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.382-384
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• 1988

The explicit form of time correlation function between fluctuating concentrations is obtained for the model of metabolic system with negative feedback near a stable(or marginally stable) steady state.