• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.66-73
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• 1997

This procedure describes the method for gas chromatographic determination of 31 organophosphorus and 28 organochlorine pesticides in 10g of spinach, tomato and onion. After the pesticides were extracted with several solvents, the amount of coextractives and recovery rates of acephate and methamidophos were calculated. Samples for organochlorine pesticides were cleaned up with florisil solid phase extraction columns. NaBH$_4$ was added to onion extracts, which contained sulfur compound. All the concentrated extracts were analyzed by gas chromatography with ECD and NPD. The smallest amount of coextractives resulted from the spinach samples extracted with 5% MeOH in ethyl acetate. 5% EOH in ethyl acetate had the highest extractability for acephate and methamidophos and gave the best overall performance as an extraction solvent. The ability of 5% EOH in ethyl acetate to extract various organophosphorus and organochlorine pesticides from spinach, tomato and onion was examined. Recovery of 59 insecticides ranged from 58.0% to 110.5%. The average recoveries of fortified spinach, tomato and onion were 90.08%, 94.54% and 84.90%, respectively.

• Resources Recycling
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• v.8 no.3
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• pp.31-36
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• 1999

In the process of manufacturing acrylonitrile, azeotrope of water-acetonitrile is formed as by-product. To1uene-ethylacetate mixture was selected as solvent to determine the liquid-liquid equilibria for to1uene(l)-water(2)-acetomtrile(3)-ethyjacetate(4) system. The experimental he-line data were correlated with the UNIFAC model. The distribution and selectivity for quaternary system was also studied.

• Membrane Journal
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• v.2 no.1
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• pp.1-20
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• 1992

Classical membrane processes like microfiltration (MF), ultrafiltration (UF) and reverse osmosis (RO) are being applied in the last years more frequently in environmental and effluent process problems. Newer technologies and developments like pervaporation (PV) and gas sepaxation (GS) recently found commercial applications in the treatment of waste waters and gas streams. The incentive here is either the clean-up from organic components to comply with federal emission regulations or the recovery of the organics for economical reasons. Processes still in their development stage are combinations of chemical reactions with membrane processes to separate and treat $SO_x$ and $NO_x$ laden waste gas streams in the clean-up of stack-gases. In this paper we will first give a short overview of the more recent developments in MF, UF and RO. This is followed by a closer look on newer technologies applied in environmental problems. The applications looked at are the recovery of organic components from solvent laden gas streams and the separation of organic volatiles from aqueous waste waters via pervaporation. Technical solutions, the advantages and disadvantages of the processes and. where possible, cost estimations will be presented.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.209-213
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• 2000

The cultured mycelia of Ganoderma lucidum were extracted and the extract was separated into six fractions by organic solvent fractionation. The antihepatotoxic activity of all the fractions was evaluated by measuring activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT). Among the fractions tested, the high-polarity fractions such as aqueous and n-butanol fractions significantly reduced activities of GPT and GOT in CCl4- and galactosamine-intoxicated rat primary hepatocytes. When intracellular synthetic activities were measured by pulsing the rate primary cultured hepatocytes with [3H]-uridine and [3H]-leucine, activities of DNA, RNA and protein. When direct toxicities of the fractions were measured against human hepatoma(SK-Hep-1), the non-polarity fractions such as n-butanol and ethyl acetate fractions showed potent direct cytotoxicities even at the concentration of 1 $\mu\textrm{g}$/ml. These data showed that Ganoderma lucidum has hepatoprotective and hepatotoxic recovery principles in its mycelia.

• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.88-92
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• 2015

In order to study the semi-conductive characteristics of carbon black-filled ethylene-propylene-diene monomer (EPDM) composite film, which is used for measuring occlusal force, composite samples with volume ratios of carbon black to EPDM ranging from 30% to 70% were prepared. The process of making a composite film consists of two steps, which involve the preparation of a slurry composition and the fabrication of a thin film using solution casting and a lamination process. To prepare the slurry composition, we dispersed carbon black nanoparticles into an organic solvent before mixing with an EPDM solution in toluene. The mechanical and electrical properties of the resulting carbon black-filled EPDM film were then investigated, and the results showed that the electrical resistance of a film decreases with the increase in the carbon black content. Furthermore, improved elastic recovery was observed after cross-linking the EPDM.

• Journal of Surface Science and Engineering
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• v.25 no.3
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• pp.150-157
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• 1992

A recovery process of pure alumina powder from the wasted aluminum etching solution of electrolytic condenser works was studied. The possibility of this process was considered in the basis of thermodynamic data nad physico-chemical properties for the recovered materials were tested. In order to obtain pure alumina, Fe3+ and Cu2+ in the solution as impurities were solvent-extracted, respectively, and then, Al3+ was precipitated by changing the pH of the solution. As the results, more than 99.9% of Al3+ in the solution was recovered by the precipitation method. The weight of the precipitate was reduced to about 65 wt.% of the original one by calcination and the sizes of the recovered powders were in order of 3-5$\mu\textrm{m}$. The precipitates were transformed to $\alpha$-Al2O3 at the calcination temperature about 120$0^{\circ}C$.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.109-122
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• 2018

This work highlights extraction and removal of Lignosulfonate using sunflower oil-Tri-n-octylamine (TOA) system in bulk liquid membrane transport. Maximum extraction and recovery percentages of 92.4% and 75.2% were achieved. Optimum manifold operating conditions were: 4 vol.% TOA, $2{\pm}0.1$ feed phase pH, 300 rpm stirring speed, at $40^{\circ}C$ with 0.2 (M) $Na_2SO_4$ solution. 1:2 (organic/aqueous) and 1:1 (aqueous/aqueous) phase ratios produced best results. Extraction (36.85 kJ/mol) was found to be intermediate controlled and stripping (54.79 kJ/mol) was chemical reaction controlled. Kinetic estimation of data with higher rate constants for stripping vis-${\grave{a}}$-vis extraction showed latter to be rate determining.

• Journal of Microbiology and Biotechnology
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• v.6 no.5
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• pp.358-360
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• 1996

Solvent extraction, soxhlet method, and supercritical fluid extracion were considered, respectively, as the method of choice for the recovery of DHA from lyophilized Thraustochitrium sp., and the results of corresponding extraction were compared. Supercritical fluid extraction seems to be the most appropriate process with respect to time, process simplicity, and extractant intoxicity.

• Proceedings of the Membrane Society of Korea Conference
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• 1992.04a
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• pp.11-28
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• 1992

In this paper we will first give a short overview of the more recent developments in MF, UF and RO. This is followed by a closer look on newer technologies applied in environmental problems. The applications looked an are the recovery of organic components from solvent laden gas streams and the separation of organic volatiles from aqueous waste waters via pervaporation. Technical solutions, the advantages and disadvantages of the processes and, where possible, cost estimations will be presented.

• KSBB Journal
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• v.8 no.1
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• pp.1-9
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• 1993

The acetone-butanol fermentation by C. acetobutylicum has gained increasing attention for the following reasons. First, the finite supply of petrochemical resources, combined with increasing concern over global environmental effects and the unstable nature of the price of petroleum has renewed interest in the development of fermentation technology that allows utilzation of biomass wastes for the production of alcohol. Second, it serves as excellent model system for understading the regulation and molecular biology of tightly regulated complex primary metabolism, and for applications of metabolic engineering. In this review various aspects of acetone-butanol fermentation by C. acetobutylicm including strain and fermentation characteristics, enzyme regulation, and solvent formation mechanism, and product recovery and summarized.