• Natural Product Sciences
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• v.7 no.1
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• pp.17-20
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• 2001

The activity of the lipase and phospholipase extracted from the seed meal of Nicotiana tabacum L. was studied with the help of Spectrophotometer at different pH, Temperatures and Solvents. Both lipase and phospholipase shown optimum activity at pH 6 and $45^{\circ}C$. Their activities also maximize when n-heptane was used as solvent media.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.107-109
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• 2012

A quasidimensional model is developed with the surrogate mechanism of isooctane and n-heptane to predict knock and emissions of a homogeneous GDI engine. It is composed of unburned and burned zone with the latter divided into multiple zones of equal mass to resolve temperature stratification. Validation is performed against measured pressure traces, NOx and CO emissions at different load and rpm conditions. Comparison is made between the empirical knock model and predictions by the chemistry model in this work.

• Fire Science and Engineering
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• v.33 no.1
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• pp.39-44
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• 2019

In this study, the relationships between the material properties of the wall and the fuel mass flux in compartment fire. The fire resistant board (fire-board) and steel plate compartments are constructed with a 0.3 m width, 0.5 m height and 3.0 m length. To obtain the mass loss rate considering the location of the fire origin in compartment, experiments of a heptane pool fire are performed with a combustion area of $0.01m^2$ and $0.0225m^2$. The results show that the initial mass flux of heptane, $0.0087kg/m^2{\cdot}s$, is increased to $0.166kg/m^2{\cdot}s$ for fire board and $0.019kg/m^2{\cdot}s$ for steel plate. It means that the fire-scenario should be considered with the thermal characteristics of the material properties and geometric shapes of the compartment to predict fire propagation accurately in a compartment space.

• Journal of Energy Engineering
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• v.17 no.1
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• pp.38-45
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• 2008

In this work, we investigated the variation of physical and chemical characteristics of solvent-insolubles and solvent-solubles in Canada's Athabasca oil sands by solvent-insolubles experiments. N-Heptane, n-Hexane, and n-Pentane were tested for solvents and asphaltenes were separated from maltenes by using a modified ASTM D 3279 method. Elemental analysis, boiling point distribution (SIMDIS), molecular weight distribution, heavy metal contents, API gravity, viscosity and SARA fractions were measured for thorough samples. The asphaltenes-removed maltenes contained less sulfur and heavy metal amounts and had lower molecular weight than the original bitumen. N-Pentane solvent could lower sulfur and heavy metal amounts, molecular weight, and viscosity of maltenes compared to the other solvents. Eventually, we confirmed that the obtained experimental data could be used as basic informations of bitumen upgrading processes for the production of SCO (synthetic crude oil).

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.416-422
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• 2001

The migration of alkylphenols from PVC packaging materials (wrap, sheet and gasket) into food simulants and foods were analyzed by reversed-phase high-performance liquid chromatography with fluorescence detection and gas chromatography with mass selective detection. Only seven nonyl phenol isomers were detected in three types of PVC food packaging materials and the content of nonyl phenol of wrap was higher than those of sheet and gasket. The contents of nonyl phenol migrated from fatty food simulants (n-heptane) were higher than those from aqeous food simulants (distilled water, 4% acetic acid and 20% ethanol) and increased with increase in temperature. Nonyl phenol in fruit juice, infant formula, and beverage was migrated from PVC gasket, olefin gasket, and olefin bottle cap, respectively. Nonyl phenol was also detected from foods even before contacting with the packaging materals.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.429-434
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• 2012

A kind of Antihistamines, Azelastine HCl which known as modern H1-blockers, was synthesized by four step process using phthalic anhydride, 4-chlorophenylacetic acid, hydrazine 2HCl. The first step was the reaction of removing carboxyl group and hydroxyl group and the second step was saponification of 3-(4-chlorobenzylidene)phthalide. The third step was the nucleophilic addition reactions of primary amines and the fourth step was addition reaction of N-methyl-1-aza-bicyclo[3,2,0]heptane to 4-(4-chlorobenzyl)-1-(2H)phthalazinone. As a result, product was analyzed by FT-IR and $^1H$-NMR and could be obtained with a yield of 80%.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.125-132
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• 2017

The effect of food simulants on properties and light barrier function of LDPE-nano $TiO_2$ composite film has been investigated. LDPE-nano $TiO_2$ composite films were prepared with 5.0wt% $TiO_2$ content by melt-extrusion. To simulate food contact environment, according to KFDA standards and specifications for food utensils, containers and packages, food simulants were selected with deionized water, 50% ethanol, 4% acetic acid and n-heptane and composite films were immersed in each food simulant at $70^{\circ}C$, 30 min except n-heptane ($25^{\circ}C$, 60 min). A variety of material properties, including crystallinity, chemical bonds, surface morphology, mechanical, oxygen barrier and optical properties, of LDPE-nano $TiO_2$ composite film were examined with and without the food simulants treatment. As a result, under regulated migration condition, LDPE-nano $TiO_2$ composite showed extremely stable in all properties tested in the study in contact with food simulants indicating that $TiO_2$ nanoparticles are physicochemically stable and quite compatible with LDPE. Results enable us to anticipate migration of $TiO_2$ will probably not occur. To evaluate influence of migration of $TiO_2$ on food stuffs, their color, pH and acidity were observed as well.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.3
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• pp.31-39
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• 1999

In this paper, numerical experiment is attempted to analyze and compare the combustion efficiency of the burning sprays due to OFO, FOF triplet / FOOF split doublet injectors. Preconditioned Wavier-Stokes equation system with low Reynolds number $\kappa$-$\varepsilon$ model for turbulence closure, is LU-SGS time-integrated. Spray processes are modeled by DSF analysis with experimentally determined injection characteristics. n-heptane/air global reaction model approximates the combustion for simplicity, and the influence of turbulence on the chemical reaction is included using eddy dissipation model. The results showed the FOF triplet injector of highest combustion efficiency, whereas the OFO type of poet performance. It was also observed that the droplet mean diameter and the average gas temperature due to the mixing efficiency, are the representative parameters for the performance design of combustion.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.1
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• pp.21-24
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• 1999

The analysis of hazard compounds, including naphthalene, biphenyls (BP) and diethyl phthalate (DEP), was conducted from the wooden kitchenwares and sanitory produce. Fifty samples of that wooden products in the local market were purchased for the study. All the samples were extracted by benzene and n-heptane, followed by the analysis through GC-MSD. As a result, neither naphthalene nor diethyl phthalate were found, however, trace amount of biphenyls were detected on all the samples ranged from 0.1 to 3.1 ppm. Biphenyls also contained both in the imported and the domestic of White Birch wood, as 0.25 ppm and 0.34 ppm, respectively. The concentration of biphenyls reduced with the process of the original woods, and especially the detection range was relatively low compared with the permission one of apples (110 ppm). The results suggested that biphenyls were contaminated into the product not by the addition doting the process of manufacture, but as the component itself in raw wood materials. Also, the content of the residual biphenyls were not suspected to give the harmful effects.

• Fire Science and Engineering
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• v.23 no.4
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• pp.13-18
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• 2009

The main objective of the present study is to investigate smoke propagation in railway tunnels with rescue stations. In particular, based on measurement of HRR (heat release rate) for pool fires formed at different locations, the influence of fire source location on smoke behavior is examined. The fuel is n-heptane and pool fires are generated with a square length 4cm. With the use of MVHS (Modified Volumetric Heat Source) model for fire source, extensive numerical simulations are performed by using the commercial code FLUENT (Ver.6.3) Predicted smoke temperatures and smoke propagation are discussed. From numerical predictions, it is found that ventilation systems may be necessary in the railway tunnels because the smoke moves along the tunnel, and consequently it enters the non-accident tunnel. It is also confirmed that the cross-passage and fire protection wall systems contribute to control the smoke.