• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.433-446
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• 2021

This study aims to identify the elasticities and casualties of financial performance and determinants of the mining and extractive companies listed in Jordan's stock market over the 2005-2018 period. The conceptual framework is based on the Resource-Based View theory and Arbitrage Pricing theory is used to describe the relationship between the external environment and the financial performance of the companies. Profitability ratio (return on assets) is utilized as a proxy of financial performance measurement. Meantime, the company's characteristics, macroeconomic variables, and non-economic factors are utilized as independent factors. Data sources are panel data set for mining and extractive companies over the above period. Fully Modified Ordinary Least Square (FMOLS), Dynamic Ordinary Least Squares (DOLS), and Pooled Mean Group (PMG) methods are applied. The empirical findings indicated that company size, sales growth, financial leverage, liquidity, and GDP growth were the critical determinants of mining and extractive companies' financial performance in the Amman Stock Exchange. Thus, the findings conclude that company characteristics and GDP growth mainly drive financial performance. Moreover, the findings reveal that a bidirectional causal elasticity exists between GDP and financial leverage and return on assets (ROA). Sound financial performance can be obtained by paying more attention to GDP growth and firms' characteristics.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2336-2347
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• 2018

The azeotrope of methyl acetate methanol and water was isolated using extractive distillation with water as entrainer. The pressure-swing extractive distillation (PSED) process and vapor side-stream distillation column (VSDC) with the rectifier process were designed to separate the methyl acetate, methanol and water mixture. It was revealed that the VSDC with the rectifier process had a reduction in energy consumption than the PSED process. Four control schemes of the two process were investigated: Double temperature control scheme (CS1), $Q_R/F$ feedforward control of reboiler duty scheme for PESD (CS2), $Q_R/F$ feedback control scheme for VSDC (CS3), the feedback control scheme of sensitive plate temperature of side-drawing distillation column to dominate the compressor shaft speed (CS4). Feed flow and composition disturbance were used to evaluate the dynamic performance. As a result, CS4 is a preferable choice for separation of methyl acetate-methanol-water mixture. A control scheme combining the operating parameters of dynamic equipment with the control indicators of static equipment was proposed in this paper. It means using the sensitive plate temperature of side-drawing column to control the compressor shaft speed. This is a new control scheme for extractive distillation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.1-11
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• 1999

Considerations of partition coefficients, selectivity, biocompatibility, and waste generation are important in selection of appropriate solvents to be used for extractive recovery of products from fermentation broths. Several selection criteria can be used based upon the nature of different species present in the broth. These criteria, along with examples of specific case studies, were presented. These serve not only in screening of useful solvents, but also in pointing to the specific modes of operation of recovery-coupled bioprocesses.

• KSBB Journal
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• v.6 no.2
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• pp.175-180
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• 1991

The quantitative effects of molecular weight and concentrations of two phase-forming polymers-polyethylene glycol and crude dextran on the two phase extractive ethanol fermentation were investigated using a Box-Wilson central composite protocol. The regression model obtained was used in order to determine optimum compositions of aqueous two phase system. In the aqueous two phase extractive ethanol fermentation of Kluyueromyces fragilis CBS 1555 with Jerusalem artichoke juice, it was found from the regression model that the variables influenlcing on ethanol fermentation were PEG concentration, time, Dx concentration, and PEG molecular weight strongly in order. The interaction of PEG concentration and PEG molecular weight was also found, and the effect of PEG concentration decreased with increase in molecular weight of PEG. The ethanol concentration incresed with increase in molecular weight of PEG, and with decrease in concentration of PEG. In conolusion, maximum concentration of ethanol produced was obtained at the following compositions; PEG MW 20000, Dx concentration ranged from 4% to 5%, and PEG concentration ranged from 3% to 7%.

• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.897-904
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• 2019

Monascus purpureus recombinant mppC and mpp7 knockout strains were subjected to extractive fermentation in the context of azaphilone pigment production. Inclusion of Diaion HP-20 resin resulted in the selective production of unreduced azaphilone congeners, in addition to the early intermediate FK17-P2a, from ${\Delta}mppC$ and ${\Delta}mpp7$ strains that would otherwise mainly produce reduced congeners. Structural determination of two novel unreduced azaphilones from the ${\Delta}mpp7$ strain was accomplished. The unreduced azaphilone compound was converted into the cognate reduced congener in recombinant M. purpureus strains, demonstrating its intermediate role in azaphilone biosynthesis. This study demonstrates the possibility that extractive fermentation with Diaion HP-20 resin can be used to obtain cryptic azaphilone metabolites.

• Journal of the Korean Wood Science and Technology
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• v.34 no.2
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• pp.68-77
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• 2006

The heartwood of cengal (Neobalanocarpus heimii) is known to have a high degree of decay resistance by virtue of its high extractive content. After 30 years in ground contact an utility pole of this tropical hardwood was found to be degraded only in the surface layers by cavity-forming soft rot fungi. The present work was undertaken 1) to characterize the degradation of cengal heartwood from the aspect of ultrastructure and chemistry and 2) to investigate the correlation between soft rot decay and its extractive microdistribution in wood tissues. The chemical analysis of cengal heartwood revealed the presence of a high amount of extractives as well as lignin. The wood contained a relatively high amount of condensed lignin and the guaiacyl units. Microscopic observations revealed that vessels, fibers and parenchyma cells (both ray and axial parenchyma) all contained extractives in their lumina, but in variable amounts. The lumina of fibers and most axial parenchyma were completely or almost completely filled with the extractives. TEM micrographs showed that cell walls were also impregnated with extractives and that pit membranes connecting parenchyma cells were well coated and impregnated with extractives. However, fungal hyphae were present in the extractive masses localized in cell lumina, and indications were that the extractives did not completely inhibit fungal growth. The extent of cell wall degradation varied with tissue types. The fibers appeared to be more susceptible to decay than vessels and parenchyma. Middle lamella was the only cell wall region which remained intact in all cell types which were severely degraded. The microscopic observations suggested a close correlation between extractive microdistribution and the pattern and extent of cell wall degradation. In addition to the toxicity to fungi, the physical constraint of the extractive material present in cengal heartwood cells is likely to have a profound effect on the growth and path of invasion of colonizing fungi, thus conferring protection to wood by restricting fungal entry into cell walls. The presence of relatively high amount of condensed lignin is also likely to be a factor in the resistance of cengal heartwood to soft rot decay.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.348-355
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• 2008

Recently, an understanding of new sources of liquid hydrocarbons such as bio-ethanol is economically very important. The present dissertation is also designed with purpose of developing the energy-saving process for the separation of bio-ethanol. In order to illustrate the predictability of proposed process for the separation of bio-ethanol, the experimental data from literatures and real plant data are used. Application of the thermodynamics of multicomponent mixtures and phase equilibria to the extractive distillation process with syntheses of heat exchanger network has enabled the development of energy-saving process for different separating agents. Developed process is capable of minimizing the energy usage and the environmental effect. This extractive process is also able to properly describe the effect of impurities, the choice of separating agent. Simulation results of extractive distillation using ethylene glycol show that impurities do not affect to extractive distillation operation and agent, ethylene glycol, was recycled without any loss. It is possible that extraction distillation has various heat network for anhydride ethanol and recovery of ethanol is maximized. Ethylene glycol as separating agent has a high boiling point to eliminate azeotropic point and on the contrary solubility of agent is low to be almost completed recovered. Proposed process is also the energy efficient process configuration in which 99.85mole% anhydride ethanol can be produced with low energy of 1.37198 (kg steam/kg anhydride ethanol).

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.13-19
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• 1999

In order to investigate the composition and the actual status of extractive nitrogenous compounds in the fresh 'Gae-bul' (echiuroid), a kind of echiurida (Urechis unicinctus), the extract was analyzed separately into extractive nitrogen, free amino acids (FAAs), oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish market in April 1988. The extractive nitrogen of echiuroid was $601{\sim}610mg/100g$. Thirty-two kinds of FAAs were found, and the total of them in it was $2,437{\sim}2,609\;mg$. Glycine, alanine, taurine, and serine were the major FAAs in the echiuroid extracts. The large amount of glycine $(1,075{\sim}1,171mg)$ was noted in the extract. The sum of ATP and its related compounds was $3.04{\sim}3.12\;{\mu}mol/g$, and predominant compound was the AMP. Besides, CTP, GTP, UTP and their related compounds were also detected, and the total amount of them was $1.92{\sim}3.74\;{\mu}mol/g$. The lower homarine, trigonelline, TMAO, TMA, and creatine were detected in the extracts. The extractive nitrogenous constituents of medium size and large size echiuroid were almost the same level each other. The total nitrogens of the compounds analyzed for each samples accounted for more than 90% of the extractive nitrogen in this study.

• Journal of Powder Materials
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• v.20 no.1
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• pp.60-67
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• 2013

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.815-824
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• 2012

Extractive distillation system can be used when the components to be separated have close boiling points or form azeotropes. Extractive distillation is one of the most important and widely used separation methods in chemical process industry. The main disadvantage of the distillation is its high-energy requirements. Thermally coupled distillation system (TCDS) can provide significant savings in energy consumption and capital cost over the operation of sequences based on conventional distillation column. Despite such advantages of the thermally coupled distillation system, the process is not widely used in industry because control and operation of the column are difficult. In this study, we propose several control schemes for thermally coupled distillation system to overcome the difficulties and make the column stable when the process is confronted with feed disturbances. Profile position control scheme shows best control performance among the proposed control schemes.