• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.123-128
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• 2002

The synergistic effect of ethylene/propane and ethylene/methane mixtures on soot formation is studied experimentally with a concentric co-flow burner. The integrated soot volume fractions, laser light scattering signal and PAH concentrations are measured for different fuel supply configurations. The synergistic effect in ethylene/propane diffusion flames is found to be affected not only by the composition of mixture but also by the way of mixing. Comparing to the homogeneously mixed ethylene/propane case, the increase of soot formation is observed when propane is supplied through the inner nozzle, while the decrease is observed when propane is supplied through the outer nozzle. However, the measured PAH concentration distributions are inconsistent with the current view of the synergistic effect of ethylene./propane mixture on soot formation. Virtually no synergistic effect is observed in ethylene-methane flames regardless of the fuel supply configuration, which suggests the important role of $C_3$ species produced during the propane pyrolysis process for the synergistic effect.

• Journal of the Korean Wood Science and Technology
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• v.50 no.1
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• pp.12-30
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• 2022

Many studies on plant extracts have been reported for the treatment of candidiasis caused by Candida albicans, a representative fungal infection. This study demonstrates the synergistic antifungal activity of the combination of Phellodendri Cortex and Magnoliae Cortex, previously reported to have antifungal efficacy. Considering the antifungal efficacy and the separation of the active constituents, berberine and magnolol, hot water extraction and carbon dioxide supercritical extraction were selected for Phellodendri Cortex and Magnoliae Cortex, respectively. A combination of 0.55 g/L hot water extract of Phellodendri Cortex and 0.59 g/L carbon dioxide supercritical extract of Magnoliae Cortex showed synergistic antifungal activity. The synergistic antifungal activity of 160 μM berberine and 100 μM magnolol, which are representative antifungal compounds of Phellodendri Cortex and Magnoliae Cortex, respectively, contributes to the synergistic antifungal effect of their extracts. The additive decrease in cellular ergosterol level and the increased antifungal efficacy by extracellular ergosterol suggest that disruption of the biological function of ergosterol in the cell membrane is not responsible for the synergistic antifungal activity of berberine and magnolol. Synergistic cellular release of chromosomal DNA upon mixing berberine and magnolol indicates that disruption of the cellular structure is responsible for the synergistic antifungal effect of berberine and magnolol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.586-592
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• 2005

This study was peformed to investigate the synergistic effects of catechin and ascorbic acid on antioxidative activities of methanol and hexane extracts (500 ppm) from rosemary, sage, oregano, and ginger. Ascorbic acid (200 ppm) and (-)-catechin (200 ppm) could be solubilized in a rice bran oil via a reverse micelles using small amount of water and dioctyl sulfosuccinate as the sufactant. Methanol extracts from rosemary, sage, oregano, and ginger showed the synergistic effects by (-)-catechin. However, methanol extracts showed the synergistic effect by ascorbic acid except that of ginger. The synergistic effects of (-)-catechin on methanol extracts were higher than those of ascorbic acid. Hexane extracts of oregano and ginger showed the synergistic effects by (-)-catechin, and no synergistic effects by ascorbic acid. On the other hand, rosemary and sage showed the synergistic effects by ascorbic acid and no synergistic effects by (-)-catechin.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.479-483
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• 1995

The synergistic extraction of palladium(Ⅱ) was studied with 1,2-dichloroethane containing thenoyltrifluoroacetone (TTA; HA) and tri-n-octylphosphine oxide (TOPO; S). The main composition of synergistic adduct extracted into 1,2-dichloroethane phase was found to be PdA2S2. The equilibrium constants of the synergistic reaction were calculated. The application of this method to synthetic mixture for the separation of Pd from Pt was developed.

• Journal of Microbiology and Biotechnology
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• v.19 no.2
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• pp.204-207
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• 2009

We investigated novel antibacterial and synergistic activities of isocryptomerin isolated from Selaginella tamariscina. Isocryptomerin showed potent antibacterial activity against Gram-positive and Gram-negative bacterial strains including clinical isolates of antibiotic-resistant species such as methicillin-resistant Staphylococcus aureus(MRSA). Additionally, we further investigated the synergistic activity of isocryptomerin with a conventional antibiotic against MRSA. The result indicated that isocryptomerin had considerable synergistic activity in combination with cefotaxime. In summary, the present study suggests that isocryptomerin may have potential as a novel therapeutic agent for treatment of infectious diseases by not only human pathogenic bacteria but also multidrug-resistant bacteria.

• Korean Journal of Microbiology
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• v.5 no.1
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• pp.7-14
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• 1967

The synergistic actions of certain antimetabolic agents for Saccharomyces cerevisiae and Lactobacillus plantarum on radiation sterilization have been studied. The used chemical agents are sorbic acid, vitamin-$K_3$, dehydroacetic acid, p-oxybutyl benzoate and nitrofurazone, those are the permitted as food preservatives. Experimental results are as following, 1) Survival fraction of yeast which was gamma-irradiated and influenced by sorbic acid or vitamin $K_3$ is much reduced than that of only irradiated respectively. 2) It seems like that the used chemicals acts synergistically on radiation sterilization. Sodium-dehydroacetate and p-oxybutyl benzoate are proved to be also synergistic but weakly. 3) Survival fraction of Lact. plantarum which was gamma-irradiated and influenced by sorbic acid, dehydroacetic acid or nitrofurazone respectively much reduced than that of only irradiated group, it can be estimated as synergistic action of chemical affected on radiation sterilization. 4) It was found that nutrient componets can affect radiation sterilization of microorganisms protectively.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1039-1046
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• 2005

The salt resistance of antibacterial activity and synergistic effect with clinically used antibiotic agents are critical factors in developing effective peptide antibiotic drugs. For this reason, we investigated the resistance of antibacterial activity to antagonism induced by NaCl and $MgCl_2$ and the synergistic effect of P20 with cefotaxime. P20 is a 20-residue synthetic peptide derived from a cecropin A (CA)-melittin(ME) hybrid peptide. In this study, P20 was found to have potent antibacterial activity against clinically isolated methicillin-resistant Staphylococcus aureus (MRSA) strains without hemolytic activity against human erythrocytes. The combination study revealed that P20 in combination with cefotaxime showed synergistic antibacterial activity in an energy-dependent manner. We also confirmed the synergism between P20 and cefotaxime by fluorescence-activated flow cytometric analysis by staining bacterial cells with propidium iodide (PI) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (BOX). This study suggests that P20 may be useful as a therapeutic antibiotic peptide with synergistic effect in combination with conventional antibiotic agents.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.140-145
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• 2009

All organisms are being exposed to harmful factors present in the environmental. The combined action of various factors is a distinguishing feature of modern life. An interaction between two chemicals is considered as synergistic when the effect produced is greater than the sum of the two single responses. The biological effects due to the combined action of ionizing radiation with the other factor are hard to estimate and predict in advance. In the current study, we investigated the synergistic effects between ionizing and $HgCl_2$ using fish hepatoma cells (PLHC-1 cells). The results showed a dramatic decrease of cell viability after simultaneous treatment of PLHC-1 cells with ionizing radiation and $HgCl_2$. Neiither of the two had any cytotoxic effect when treated alone. The cytotoxicity of ionizing radiation was enhanced in the presence of $HgCl_2$. The synergistic effects were observed after exposure of the PLHC-1 cells to ionizing radiation combined with $HgCl_2$. The synergistic interaction was due to an increase of irreversibly damaged cells after the combined exposure. Analysis of the extent of synergistic interaction enables to make quantitative estimation of irreversibly damaged cells after the combined exposure. The present study suggests that PLHC-1 cells can serve as rapid screening tools for detecting the toxicity of harmful factors.

• Asia pacific journal of information systems
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• v.23 no.1
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• pp.107-132
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• 2013

Despite the importance of knowledge complementarities (KC) to firm performance, very little is known about exactly what constitutes KC and how synergistic knowledge is created in KC. This research looks into the dimensionality of KC and how synergistic knowledge as an essential component of KC is generated in a process innovation (PI) project. We propose that KC consists of potential complementary knowledge, collaborative elaboration (CE) process, and synergistic knowledge. The model is investigated quantitatively, using a sample of 26 matched-pairs of client and consultant who participated in a PI project, and then qualitatively using interviews of a sub-sample of 7 matched-pairs of client and consultant. Data were collected in a longitudinal way at four different points during the four month project period. Results show that consultant's learning about the client's business occurs first and then client learning about IT capabilities follows through CE. With this enhanced clients' knowledge about IT capabilities, clients play an initiative role in designing the To-Be business processes, while consultants play a supporting role by introducing best practices or making suggestions based on their experiences. Future research implications as well as practical implications are also discussed.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.1175-1184
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• 2020

This research examines the personal (i.e., Machiavellianism) and situational factors (i.e., tax climate) that are believed to be psychologically salient aspects in tax compliance. To the best of our knowledge, no research has been carried out to investigate the interaction effect of the two factors. This study uses a paper-and-pencil laboratory experiment 2x2 between-subject factorial design that involved 158 participants. The results indicate that a taxpayer who has a low Machiavellianism score or who is in a high synergistic tax climate reports a higher level of income. In the high synergistic tax climate, where tax norms apply, personal ethics do not play a significant role in tax compliance decisions. Where the synergistic relationship between taxpayer and authorities is low, personal ethics play an important role, i.e., low Machiavellians report a higher reported income than high Machiavellians do. This research contributes to the literature that deviates from the traditional model of tax compliance. Taxpayers are not always rational, but they might pay tax for reasons other than financial motives (Alm, 1991, 2018), that is, personal ethics in this study. This research implies the need for policymakers to consider other approaches rather than only relying on audits and fines.