• Title/Summary/Keyword: Gibbs effect

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Genetic Correlation of Reproductive Trait in Pigs by Parity (돼지 번식형질의 산차간 유전상관)

  • Cho, Kyu-Ho;Kim, Myung-Jick;Lee, Il-Joo;Kim, In-Cheul;Jeon, Gwang-Joo
    • Journal of Animal Science and Technology
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    • v.50 no.4
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    • pp.457-464
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    • 2008
  • Heritability and genetic correlation for reproductive traits in Yorkshire pig breed were estimated using Bayesian method via Gibbs sampling. The data set consisted of 9,609 reproductive records at pig breeding farm in Korea. For estimating those parameters using Gibbs sampling, 5,000 cycles of ‘burn-in’ period were discarded among a total of 55,000 samples. Out of the remaining 50,000 samples, 5,000 estimates by each parameter were retained and used for analyses to avoid any correlation among adjacent samples. The reproductive trait considered in this study were total number of born piglets(TNB) and estimated by two different models. The estimated heritability and permanent environmental effect using Gibbs sampler were 0.12±0.020 and 10.9±1.63, respectively. Estimated genetic correlations considered parities as different traits were distributed from 0.99 to -0.13. Such results indicated that reproductive traits for sows should be considered as different traits.

Experimental Measurement and Correlation of two α-Amino Acids Solubility in Aqueous Salts Solutions from 298.15 to 323.15 K

  • Abualreish, Mustafa Jaipallah;Noubigh, Adel
    • Korean Chemical Engineering Research
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    • v.58 no.1
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    • pp.98-105
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    • 2020
  • By the gravimetric method at atmospheric pressure, the solubility of two α-amino acids was resolved over temperatures from (293.15 to 323.15) K. The α-amino acids studied were L-arginine and L-histidine. Results showed a salting-out effect on the solubility of the tested amino compounds. It is obvious that there was an increase in the solubility, in aqueous chloride solutions, with the increasing temperature. Results were translated regarding the salt hydration shells and the ability of the solute to form hydrogen-bond with water. The solubility data was precisely associated with a semi-empirical equation. The standard molar Gibbs free energies of transfer of selected α-amino compounds (ΔtrGo) from pure water to aqueous solutions of the chloride salts have been calculated from the solubility data. The decrease in solubility is correlated to the positive (ΔtrGo) value which is most part of the enthalpic origin.

The Impact of Foreign Ownership on Capital Structure: Empirical Evidence from Listed Firms in Vietnam

  • NGUYEN, Van Diep;DUONG, Quynh Nga
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.2
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    • pp.363-370
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    • 2022
  • The study aims to probe the impact of foreign ownership on Vietnamese listed firms' capital structure. This study employs panel data of 288 non-financial firms listed on the Ho Chi Minh City stock exchange (HOSE) and Ha Noi stock exchange (HNX) in 2015-2019. In this research, we applied a Bayesian linear regression method to provide probabilistic explanations of the model uncertainty and effect of foreign ownership on the capital structure of non-financial listed enterprises in Vietnam. The findings of experimental analysis by Bayesian linear regression method through Markov chain Monte Carlo (MCMC) technique combined with Gibbs sampler suggest that foreign ownership has substantial adverse effects on the firms' capital structure. Our findings also indicate that a firm's size, age, and growth opportunities all have a strong positive and significant effect on its debt ratio. We found that the firms' profitability, tangible assets, and liquidity negatively and strongly affect firms' capital structure. Meanwhile, there is a low negative impact of dividends and inflation on the debt ratio. This research has ramifications for business managers since it improves a company's financial resources by developing a strong capital structure and considering foreign investment as a source of funding.

Bayesian analysis of finite mixture model with cluster-specific random effects (군집 특정 변량효과를 포함한 유한 혼합 모형의 베이지안 분석)

  • Lee, Hyejin;Kyung, Minjung
    • The Korean Journal of Applied Statistics
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    • v.30 no.1
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    • pp.57-68
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    • 2017
  • Clustering algorithms attempt to find a partition of a finite set of objects in to a potentially predetermined number of nonempty subsets. Gibbs sampling of a normal mixture of linear mixed regressions with a Dirichlet prior distribution calculates posterior probabilities when the number of clusters was known. Our approach provides simultaneous partitioning and parameter estimation with the computation of classification probabilities. A Monte Carlo study of curve estimation results showed that the model was useful for function estimation. Examples are given to show how these models perform on real data.

Effect of NaCl, n-Butanol, and Temperature on the Micellization of Ammonium Cationic Surfactants (DTAB, TTAB, and CTAB) in Aniline Solution (아닐린 수용액에서 암모늄형 양이온성계면활성제 (DTAB, TTAB, 및 CTAB)의 미셀화에 미치는 염, n-부탄올 및 온도의 효과)

  • Lee, Dong-Cheol;Lee, Byung-Hwan
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.2
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    • pp.407-416
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    • 2019
  • The criticical micelle concentration (CMC) was measured by using the UV-Vis method for the micellization of the ammonium type cationic surfactants (DTAB, TTAB, and CTAB) in the aqueous aniline solution. The enthalpy change (${\Delta}H^0$) and entropy change (${\Delta}S^0$) were calculated from the dependence of Gibbs free energy change (${\Delta}G^0$) on the temperature for micellization of the cationic surfactants between 290K and 314K. The effects of n-butanol and sodium chloride on the micellization of cationic surfactants were measured and compared with the other thermodynamic functions. All the free energy changes (${\Delta}G^0$) of the micellization were negative, all the enthalpy change (${\Delta}H^0$) were negative, and all the entropy change (${\Delta}S^0$) were positive values, respectively. The micelle formation of cationic surfactant in aniline solution is a spontaneous exothermic reaction, and the iso-structural temperature calculated from the thermodynamic values show that enthalpy and entropy contribution to the micellization are almost the same for the micellization of cationic surfactants

Separation Characteristics of Aqueous Isopropanol Solution by Pervaporation (투과증발에 의한 이소프로판올 수용액의 분리특성)

  • 이규일;김현진;김진환
    • Membrane Journal
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    • v.6 no.1
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    • pp.22-31
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    • 1996
  • Pervaporation experiments of isopropanol-water mixtures through a polydimethytsiloxane(PDMS) membrane were carried out at 35$^{\circ}$C and the effect of isopropanol concentration on the separation characteristics was investigated. The total permeation rate showed the largest deviation from the ideal permeation rate at the isoprpanol volume fraction from 0.5 to 0.7, which resulted from the interaction effect between permeants. The plasticizing effect of isopropanol enhanced the permeation of water, while the existance of water resulted in the depression of isopropanol permeation. Both the permeation rate and the selectivity were predicted using Flory-Huggins thermodynamics and modified Maxwell-Stefan equation. The concentration-dependent diffusion coefficients were expressed by Vignes equation. The Flory-Huggins interaction parameter between isopropanol and water was calculated using excess Gibbs energy correlation and the interaction parameters between liquid and polymer membrane were determined by equilibrium swelling experiments. The predicted permeation rates were in accord with the experimental ones within maximum error range of 35 %. The predicted permeation selectivities were in good agreement with the experimental values.

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Aminopropyl Functionalized Silica Nanoparticle Dispersed Nafion Composite Membranes for Vanadium Redox Flow Batteries (아미노프로필 관능기를 갖는 실리카 나노 입자가 분산된 나피온 복합막을 이용한 바나듐 레독스 흐름 전지)

  • Lee, Doohee;Yu, Duk Man;Yoon, Sang Jun;Kim, Sangwon;So, Soonyong;Hong, Young Taik
    • Membrane Journal
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    • v.30 no.5
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    • pp.307-318
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    • 2020
  • Conventional perfluorinated sulfonic acid membrane, Nafion is widely used for vanadium redox flow battery (VRFB). It is desired to prevent vanadium ion permeation through a membrane to retain the capacity, and to keep the cell efficiency of a VRFB. Highly proton conductive and chemically stable Nafion membranes, however, suffer from high vanadium permeation, which induce the reduction in charge and discharge capacity by side reactions of vanadium ions. In this study, to resolve the issue, silica nanoparticles, which are functionalized with 3-aminopropyl group (fS) are introduced to enhance the long-term performance of a VRFB by lowering vanadium permeation. It is expected that amine groups on silica nanoparticles are converted to positive ammonium ion, which could deteriorate positively charged vanadium ions' crossover by Gibbs-Donnan effect. There is reduction in proton conductivity may due to acid-base complexation between fS and Nafion side chains, but ion selectivity of proton to vanadium ion is enhanced by introducing fS to Nafion membranes. With the composite membranes of Nafion and fS, VRFBs maintain their discharge capacity up to 80% at a high current density of 150 mA/㎠ during 200 cycles.

Solvent Effect on Relative Gibbs Free Energy and Structural Property of $Eu^{3+}\;to\;Yb^{3+}$ Ion Mutation: A Monte Carlo Simulation Study

  • Kim, Hak Seong
    • Bulletin of the Korean Chemical Society
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    • v.22 no.8
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    • pp.877-882
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    • 2001
  • The solvent effects on the relative free energies of Eu3+ to Yb3+ ion mutation in solution have been investigated using a Monte Carlo simulation of statistical perturbation theory (SPT). Our results agree well with available data that were obtained by others. Particularly, the results of water (SPC/E) solvent are almost identical with experimental data. For the present Eu3+ and Yb3+ ions, the relative free energies of solvation vs. Born’s function of bulk solvents decrease with increasing Born’s function of bulk solvents. There is also good agreement between the calculated structural properties in this study and the published works obtained by computer simulation and experimental work.

Analysis on Isotherm, Kinetic and Thermodynamic Properties for Adsorption of Acid Fuchsin Dye by Activated Carbon (활성탄에 의한 Acid Fuchsin 염료의 흡착에 대한 등온선, 동력학 및 열역학 특성치에 대한 해석)

  • Lee, Jong Jib
    • Korean Chemical Engineering Research
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    • v.58 no.3
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    • pp.458-465
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    • 2020
  • Isotherms, kinetics and thermodynamic properties for adsorption of acid fuchsin (AF) dye by activated carbon were carried out using variables such as dose of adsorbent, pH, initial concentration and contact time and temperature. The effect of pH on adsorption of AF showed a bathtub with high adsorption percentage in acidic (pH 8). Isothermal adsorption data were fitted to the Freundlich, Langmuir, and Dubinin-Radushkevich isotherm models. Freundlich isothem model showed the highest agreement and confirmed that the adsorption mechanism was multilayer adsorption. It was found that adsorption capacity increased with increasing temperature. Freundlich's separation factor showed that this adsorption process was an favorable treatment process. Estimated adsorption energy by Dubinin-Radushkevich isotherm model indicated that the adsorption of AF by activated carbon is a physical adsorption. Adsorption kinetics was found to follow the pseudo-second-order kinetic model. Surface diffusion at adsorption site was evaluated as a rate controlling step by the intraparticle diffusion model. Thermodynamic parameters such as activation energy, Gibbs free energy, enthalpy entropy and isosteric heat of adsorption were investigated. The activation energy and enthalpy change of the adsorption process were 21.19 kJ / mol and 23.05 kJ / mol, respectively. Gibbs free energy was found that the adsorption reaction became more spontaneously with increasing temperature. Positive entropy was indicated that this process was irreversible. The isosteric heat of adsorption was indicated physical adsorption in nature.

Adsorption Behavior and Kinetic Characteristic of Cibacron Brilliant Red 3B-A by Granular Activated Carbon (입상활성탄에 의한 Cibacron Brilliant Red 3B-A의 흡착거동 및 동력학적 특성)

  • Lee, Jong Jib
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.486-491
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    • 2014
  • In this paper, the adsorption behavior and kinetic characteristics of cibacron brilliant red 3B-A from aqueous solution using granular activated carbon were investigated. The effect of various parameters such as adsorbent dose, pH, initial concentration, contact time and temperature on the adsorption system were studied. Base on the estimated Langmuir constant ($R_L$) and Freundlich constant (1/n), This process could be employed as effective treatment method. From the Temkin constant (B) and Dubinin-Radushkevich constant (E), This adsorption process is physical adsorption. From kinetic experiments, the adsorption process followed the pseudo second order model with good correlation. Base on the Gibbs free energy and enthalpy, the adsorption of cibacron brilliant red 3B-A onto granular activated carbon was physisorption and endothermic in nature.