• Polymer(Korea)
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• v.39 no.1
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• pp.46-55
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• 2015

There is a limit for deforestation in order to keep the environmental cycle undisturbed. The heart of the paper is to replace the wood to a maximum extent to obtain a sustainable environment. This research aims at new natural composites in which treated hemp fiber used as reinforcement, synthetic cellulose used as particulate to improve the adhesion between matrix - fiber interface and Epoxy LY556 acted as matrix fabricated by hand layup technique. The density, water absorption, tensile properties, impact strength, hardness, flexural properties and compressive properties have been evaluated under ASTM standards and compare the results with existing materials such as wood, aluminium, etc., The composite hemp fiber reinforced polymer (HFRP) could be exploited as an effective replacement for wood and it would be suitable for automotive applications by comparing results.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.6
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• pp.615-623
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• 2003

This study has been conducted to develop brown stock with the high pressure cooking(HPC) method. The sterilization methods, package film and storage methods, and quality maintenance during storage were investigated in this study. The packaging quality of NY/PP was inferior to that of PE/AL/PP since NY/PP facilitated the ventilation and moisture absorption. The maximum duration of the safe storage was found to be 50 days at 25$^{\circ}C$, 30 days at 35$^{\circ}C$ for NY/PP package film, and 60 days at 25$^{\circ}C$, 40 days at 35$^{\circ}C$ for PE/AL/PP one. These results showed that the overall quality of brown stock by the HPC method was not different significantly from that of brown stock by the traditional approach. Furthermore, the HPC approach might improve the productivity by saving the labour cost, food cost, and cooking time. Therefore, the traditional method might well be substituted by this newly developed method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.41-42
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• 2015

The concrete aggregate generates carbon dioxide in production but its demanding is gradually increased in accordance with the depletion of natural resources. Therefore we evaluated compatibility and basic physical properties of Silicon manganese slag generated in iron production as an applicable concrete aggregate. In our test, the silicon maganese slag shows 2.8g/㎥ of density in 10mm of maximum particle size similar to a natural aggregate, and its absorption rate was 0.3% similar to the electric furnace slag. Unit volume weight and ratio of absolute volume was respectively 2,001㎏/㎥ and 51%. Strength properties of Silicon manganese slag will be evaluated with further studies and experiments.

• Steel and Composite Structures
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• v.25 no.3
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• pp.327-335
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• 2017

To gain more knowledge of aluminum foam sandwich structure and promote the engineering application, aluminum foam sandwich consisting of 7050 matrix aluminum foam core and 304 stainless steel face-sheets was studied under three-point bending by WDW-T100 electronic universal tensile testing machine in this work. Results showed that when aluminum foam core was reinforced by 304 steel face-sheets, its load carrying capacity improved dramatically. The maximum load of AFS in three-point bending increased with the foam core density or face-sheet thickness monotonically. And also when foam core was reinforced by 304 steel panels, the energy absorption ability of foam came into play effectively. There was a clear plastic platform in the load-displacement curve of AFS in three-point bending. No crack of 304 steel happened in the present tests. Two collapse modes appeared, mode A comprised plastic hinge formation at the mid-span of the sandwich beam, with shear yielding of the core. Mode B consisted of plastic hinge formation both at mid-span and at the outer supports.

• Ceramist
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• v.10 no.3
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• pp.7-14
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• 2007

PbS QDs in glasses have attracted much attention due to the potentials for near-infrared applications. Growth of PbS QDs in the glass is discussed and size of PbS QDs formed in the glass can be tuned by varying the thermal treatment conditions. Hyperbolic-band approximation and four-band envelope function provide good simulation of the exciton energies of PbS QDs. Absorption and photoluminescence of PbS QDs was tuned into $1{\sim}2{\mu}m$ wave-length regime with large full width at half maximum photoluminescence intensity (>160 nm). Photoluminescence intensity of PbS QDs in the glasses was closely related to size of quantum dots, temperature, excitation and defects. Decrease in temperature shifted the photoluminescence bands to shorter wavelength and switched the photoluminescence from darkened state and brightened state.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.213-215
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• 2004

An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. The method is based on the oxidation of hydrazine by a known excess of iodate in the presence of hydrochloric acid. The unreacted iodate is used in the oxidation of hydroxylamine to nitrite. Sulfanilic acid is diazotized by the nitrite formed. The resulting diazonium ion is coupled with N-(1-naphthyl)ethylenediamine to form a stable azo dye, which shows an absorption maximum at 540 nm. Hydrazine can be determined in the range of 20-400 ng $mL^{-1}$ with a detection limit of 3.1 ng $mL^{-1}$. The relative standard deviation for 50, 200 and 400 ng $mL^{-1}$ of hydrazine is 2, 1.5 and 1.3%, respectively (n = 10). The method was applied to the determination of hydrazine in water samples.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.582-584
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• 2004

The light-emitting properties of poly(2-triethylgermyl-1,4-phenylenevinylene) (TEG-PPV) are compared with those of the silyl-substituted PPV homologue, poly(2-trimethylsilyl-1,4phenylenevinylene) (TMS-PPV). The precursor polymer is solution-processable. After carrying out thermal elimination on the precursor polymer film, the resulting fully conjugated polymer film was found to exhibit high thermal stability in air, and absorption that is shifted to the longer wavelength region owing to the extension of the n-conjugated system. TEG-PPV exhibits efficient green light emission; the maximum PL emission of a TEG-PPV thin film was found to be at 515 nm. The HOMO and LUMO energy levels were also determined using photo-emission spectroscopy. The performance of the TEG-PPV EL device was found to be comparable to that of the TMS-PPV device.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.6
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• pp.471-478
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• 2002

Vacuum evaporated cadmium sulphide (CdS) thin films were implanted with $Ar^+$ and $N^+$ for different doses. The properties of the ion implanted CdS thin films have been analysed using XRD, optical transmittance spectra, and Raman scattering studies. Formation of Cd metallic clusters were observed in ion implanted films. The band gap of $Ar^+$ doped films decreased from 2.385 eV of the undoped film to 2.28 eV for the maximum doping. In the case of $N^+$ doped film the band gap decreased from 2.385 to 2.301 eV, whereas the absorption coefficient values increased with the increase of implantation dose. On implantation of both types of ions, the Raman peak position appeared at $299\textrm{cm}^{-1}$ and the FWHM changed with the ion dose.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.83-84
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• 2003

The microstructure and tensile properties of ramie treated with NaOH and crosslinked with 1, 2, 3, 4-butanetetracarboxylic acid were characterised. X-ray diffraction and FTIR were used to study the crystalline structure o f the resultant ramie yarns. Results showed that the maximum change in the structure of the modified ramie took place at 16% NaOH, which would completely transform Cellulose I to Cellulose II. Also, the crystallinity index and fibre orientation decreased to the minimum value while the absorption properties were enhanced. The average degree of polymerization of the treated ramie yams slightly decreased after NaOH treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1125-1131
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• 1998

The rheological properties of wheat flour dough were investigated in the dough added with 0, 10, 15, 20, 25 and 30% of wheat bran. The ratios of ash contents in wheat flour and wheat bran were 0.43% and 5.28%, respectively. The ratios of fiber contents in wheat flour and wheat bran were 0.18% and 11.86%, respectively. The farinograph water absorption was increased as the amount of wheat bran was increased. Both arrival time and development time of the dough added with wheat bran were longer than those of wheat flour. As the amount of wheat bran was increased, the weakness was increased. The extensograph showed that extensibility and resistance to extension of dough were decreased, while the ratio of resistance to extensibility(R/E) was increased with increasing the amo unt of wheat bran. The maximum viscosity by amylograph was decreased gradually with the adding amount of wheat bran, while the gelatinization temperature was slightly increased with wheat bran.