• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.4
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• pp.65-74
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• 2013

In the manufacture of corrugated box, the fibrous raw materials are mainly consisted of recycled papers, such as KOCC(Korean Old Corrugated Container), kraft sack, and AOCC(American Old Corrugated Container). Among these recycled waste paper, the proportion of KOCC is relatively higher than others in fibrous raw materials. Generally, KOCC shows some poor fiber properties and contains hazardous heavy metal sources. Therefore, it is to evaluate the property of recycled paper sources for eco-friendly corrugated box manufacture. In this study, the physical and mechanical properties of 3 kinds of recycled fibers and their mixed stocks were analyzed. The environmental assessment was also evaluated by analyzing the 4 representative heavy metal contents and evaporation residues in waste papers. As the results, KOCC showed the poorest fiber qualities and had the highest heavy metal contents and evaporation residues among the recycled fibers. Finally, the mechanical strength properties were increased by decreasing KOCC proportion of mixed stock conditions. In addition, the heavy metal contents and evaporation residues were also decreased by increasing recycled AOCC and kraft sack proportion.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.479-485
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• 1990

For the automation of a evaporation process, computer based evaporation system was built and applied to acquisition of the process variables with an centrifugal thin film evaporator(Centri-Therm, CT-1B). Controls of the process conditions were performed by computer system for pressure, feeding rate, steam, evaporation temperature and flow rate of cooling water. The data acquisitions were also performed by computer system for the changes in the concentration and temperature readings for steam, evaporation and cooling water at the both inlet and outlet. The control and the acquisition variables were collected through the interface device and analyzed by programs using the PASCAL language. To control the feeding rate during the concentration process, inverter was used. The cooling water for the vapor condensation was controlled by the valve controller and should be supplied with the flow rate of 125 kg/h. The maximum vapor condensation rate was 41.7kg/h at the feeding rate of 125 kg/h.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.2
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• pp.81-86
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• 2008

ZnO nanowires were synthesized by the thermal evaporation method and their growth mechanisms were confirmed by the characterization of the structural features depending on the growth conditions. The increase of vaporization temperature accelerates the growth rate and morphologies of ZnO nanowires were drastically changed at the temperature over 1000$^{\circ}C$, because of changed $CO/CO_2$ partial pressure. Au particles play their role on growth of ZnO nanowire as catalyst at growth temperature over 700$^{\circ}C$. The synthesized ZnO nanowires exhibit blue emission at 380 nm.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.7
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• pp.911-918
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• 2002

Evaporation heat transfer coefficients of carbon dioxide($CO_2$), R-22, and R-134a in a horizontal smooth tube were measured and analyzed as a function of heat flux, mass flux, and evaporating temperature. The experiments were carried out by varying heat flux from 10 to 20 $kW/m^2$, mass flux from 170 to 340 $kg/m^2s$, and saturation temperatures of 5 and $10^{\circ}C$. It was found that the heat transfer coefficient of $CO_2$ decreased with a rise of quality due to an earlier liquid-film dryout as compared to R-22 and R-134a. Averaged heat transfer coefficients of $CO_2$ were 22-63% higher than those of R-22 and R-134a at all test conditions. The effects of mass flux and heat flux on averaged heat transfer coefficients were much greater in $CO_2$ than in R-22 and R-134a. When comparing $CO_2$ test results with the correlations in the literature, the existing models yielded large deviations at medium and high qualities. Therefore, a generalized correlation for $CO_2$evaporation heat transfer needs to be developed by including the effects of dryout phenomenon.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.27-34
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• 2001

A new functionally gradient metal coating method using an atomic mixing technique was developed. In this work the effect of silver atomic mixing on the tribological characteristics of silver$.$ films. has been investigated experimentally. Atomic mixing was implemented by using the, bombardment .of accelerated Ar ions during the thermal evaporation coating process of silver films. Experiments were performed in dry conditions using a ball-on-disk test rig at a load range of 19.6 mN - 17.64 N and a sliding velocity of 20 mm/sec. Results showed that the life of functionally gradient silver coating was enhanced about 100 times more than that of thermally evaporated silver coating and 2 times more than that of IBAD silver coating. The functionally gradient. film also showed low friction and wear compared to those of the evaporated silver and

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.523-532
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• 1999

This study is aimed to obtain fundamental knowledge of pulse laser welding phenomena the authors investigated the structure and composition of evaporated particles of Al alloys in air and in the Ar atmosphere during pulsed laser welding. The ultra-fine particles of 5 to 100nm diameter in a globular or irregular shape were formed in laser-induced plasma and the main structure was $MgAl_2O_4$ The composition of particles was ifferent depending on the power density of a laser beam; namely under the low power density conditions magnesium was predominant in the parti-cles while aluminium content increased with an increase in the power density. These results were attributed to evaporation phenomena of metals with different boiling points and latent heats of vaporization. On the other hand the number density of laser-induced plasma species was obtained by Saha's equation. it was confirmed that the number density depends upon the plasma tempera-ture and total pressures.

• Journal of the Korean Vacuum Society
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• v.9 no.1
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• pp.60-68
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• 2000

The optical constants ($E_g^d$, n, K) of the polycrystalline CdSe thin films deposited on the glass substrate by the electron-beam evaporation technique are determined over 400~2,500 nm photon wavelengths. In order to explain the variation of the optical contents with film thickness and substrate temperatures, the surface microstructural parameter are investigated by AFM (atomic forced microscope( images for the films deposited by different growth conditions. It is shown that the variations of optical constants are close related to changes of the surface morphology of the CdSe thin films. The decrease in the band gap with film thickness is connected with quantum size effects due to increase of the grain size. The refractive index of CdSe films decrease with increasing the grain size of the films, and the dispersion of the refractive index followed a single oscillator model according to the Sellmeier formulation.

• Korean Journal of Materials Research
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• v.9 no.7
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• pp.707-714
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• 1999

To save electrical energy as much as 40 % for fluorescent lighting, the reflectors coated with silver reflective thin films recently became popular with higher reflectivities and long life. The thin films fabricated by using sputtering techniques are produced mainly in U.S.A. On the other hand, some silver films deposited by using evaporation methods show low adhesion in general, although the reflectivity is no problem. We have studied various PVD methods to obtain thin films with high reflectivity and adhesion on a substrate of polyester, for a couple of years. Silver films manufactured byusing evaporation showed the reflectivity of 96.4 % and the adhesion of $12 kg/\textrm{cm}^2$. while samples manufactured by using sputtering depicted the adhesion as much as $20 Kg/\textrm{cm}^2$ that is almost double, although their reflectivity was not much different. X-ray diffraction spectra for the sputtered films demonstrated a preferential growth on (111) plane and the cross-sections of the specimens revealed a dense columnar structure to result in the enhanced adhesion.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.2
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• pp.55-63
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• 1985

This study is focused on deposition process leading to inefficiency and hot corrosion in fossil fuel-fired furnaces and engines. An improved understanding of the coupled thermodynamics, kinetics, and transport processes governing the deposition rate of inorganic oxides and salts from hot gases containing these compounds can suggest more efficient test strategies and control measures. Accordingly, an optical re-evaporation method for accurately measuring the growth rate of deposits under laboratory burner conditions has been developed. To demonstrate the technique and provide data suitable for theoretical model development, a deliberately simple chemical system and target geometry are used. Potassium sulfate(K$_{2}$SO$_{4}$)is introduced into a premixed propane-air flat flame at atmospheric pressure. The growth rate of $K_{2}$SO$_{4}$ on an electrically heated Pt ribbon is measured by re-evaporation technique.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.97-100
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• 2014

The combustion and emission characteristics of propane and n-butane which are the main components of LPG were compared with gasoline. The experiment was performed in a stratified DISI engine under lean combustion conditions. Mixtures of propane and n-butane wre more homogeneous because propane and n-butane have better evaporation characteristics. As a result, combustion speeds of n-butane and propane were slower, and emission levels of NOx and PM were lower. However, in spite of better evaporation, PM from propane was higher.