• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.225-230
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• 1998

A comparative study of major brands of domestic and imported cigarettes saled in market has been conducted. The total amounts of total particulate matter(TPM), tar and nicotine delivered from cigarettes, as well as the amounts of tar, nicotine in puff by puff were determined in the mainstream smoke of 6 brands. In addition, the relative amounts of vapour phase in 3rd puff smoke were determined. Results showed that the amounts of TPM and tar delivered from domestic brands were similar to the imported brands and the amounts of total nicotine delivered from domestic brands were higher than those of imported brands. As the domestic cigarettes nicotine/tar(N/T X 100) ratio was 9.5-10.3, the imported one's was 5.6-8.1. However, the amounts of tar and nicotine in puff by puff for the domestic brands were lower than those of the imported cigarettes and the relative amounts of vapour phase in 3rd puff smoke for the domestic cigarettes were lower than those of the imported cigarettes.

• Tribology and Lubricants
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• v.13 no.4
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• pp.60-65
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• 1997

The tungsten disulfide $(WS_2)$ solid lubricant was synthesized by two different reaction processes, i.e., the reaction between $CS_2$ gas phase and solid $WO_3$powder, and the vapour phase transport method of tungsten and sulfur in a high vacuum. The chemical and physical characteristics of synthesized $WS_2$powder were analyzed in terms of the average particle size, morphology, crystalline phase etc. in comparison with those of commercial $WS_2$powder. The solid $WO_3$ powder with the average size of 0.2 ${\mu}{\textrm}{m}$ was reacted with $CS_2$gas flowed with$N_2$or 96%$N_2{\times}4%H_2$forming gas for 36 h and 24 h at 90$0^{\circ}C$ respectively. $WS_2$ crystalline phase was then formed through the intermediate phase of .$W_{20}O_{58}$ In the case of vapour phase transport method, the 3.5 wt% iodine was added as a vapour transport reagent into the composition of tungsten and sulfur powders maintaining a constant molar ratio of W:S=1:2.2. The mixture was then heat treated at 85$0^{\circ}C$ for 2 weeks in vacuum. The reaction product obtained showed the average size of 12 ${\mu}{\textrm}{m}$ and the hexagonal plate shape of typical solid lubricant with 2H-$WS_2$crystalline phase.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.211-216
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• 1997

The tungsten disulfide (WS$_2$) solid lubricant was synthesized by two different reaction processes, and the chemical and physical characteristics of synthesized WS$_2$ powder were analyzed in terms of the average particle size, morphology, crystalline phase. The solid WO$_3$ powder with the average size of 0.2 $\mu$m was reacted with CS$_2$ gas flowed with N$_2$ or 96% N$_2$ + 4% H$_2$ forming gas for 36 h and 24 h at 900$\circ$C respectively. In the case of vapour phase transport method, the 3.5 wt% iodine was added as a vapour transport reagent into the composition of tungsten and sulfur powders maintaining a constant molar ratio of W : S = 1 : 2.2. The mixture was then heat treated at 850$\circ$C for 2 weeks in vacuum The reaction product obtained showed the average size of 12 $\mu$m and the hexagonal plate shape of typical solid lubricant with 2H-WS$_2$ crystalline phase.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.2 no.1
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• pp.76-85
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• 1992

${\beta}-$Ag_2S$(high temperature phase) was grown by solid/vapour reaction growth based on solid -state electrochemisty. In S/V growth, one of the reactants, silver ion, is supplied to the growth surface through the solid $Ag_2S$ from one side and the other reactants, surfur, is transported in the phase of vapour from the other side. With the sufficient supply of S vapour, the growth rate increased as increasing $T_d$(decomposition temperature of $Ag_2S$) and ${\Delta}T$ between $T_d$ and $T_g$(temperature of growth surface). At low S vapour pressure, growth rate decreased with decreased vapour pressure and ${\beta}-$Ag_2S$ was grown in the form of whisker, when Ag+ion is sufficiently supplied. The measured values of electronic conductivity of ${\beta}-$Ag_2S$ showed that electronic conductivity of the poly crystal was larger than that of single crystal.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.205-209
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• 1998

This study was conducted to evaluate the effect of triacetin(TA) treatment during manufacturing carbon dual filter for the adsorption of cigarette smoke components by activated carbons. The measurements were carried out by separation of activated carbon from carbon dual filter, and the specific surface area analyzed. The specific surface area of activated carbon from the domestic cigarette filter and from the foreign cigarette filter by degassing at 9$0^{\circ}C$ was 163$\pm$32$m^2$/g, and 16.6$\pm$1.9$m^2$/g, respectively. Those values were very lower than that of degassing at 35$0^{\circ}C$ (Domestic brand: 952$\pm$30$m^2$/g, and Foreign brand: 847$\pm$73$m^2$/g). By comparing the adsorption capacity of acetone and benzene with and without triacetin treated activated carbon, there was a 20% reduction of adsorption capacity by 5% triacetin treatment. Also, from the cilia toxicity test with carbon dual filter treated 0 % TA and 8 % TA, the cilia survival time was 706$\pm$74sec. and 603$\pm$64sec. for 0% TA and 8% TA, respectively. The delivery rate of vapour phase of cigarette smoke, which consists of main components of cilia toxicity, was higher at 8% TA filter than 0 % TA filter. Our results indicate that the treated TA covered the micro-pore of activated carbon, and then reduced specific surface area, finally, decreased the adsorption of vapour phase from cigarette smoke.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.359-366
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• 2006

The protective effect of kresoxim-methyl was investigated on 6 important plant diseases, and the vapour effect of it did on barley and cucumber powdery mildews, respectively. With 2.0 ${\mu}g\;mL^{-1}$ of kresoxim-methyl, its high activities against wheat leaf rust and barley powdery mildew were showed such as 92 and 100%, while activities were very low against rice sheath blight, tomato gray mold, and tomato late blight. In vapour phase control activity of kresoxim-methyl against barley powdery mildew was positively correlated with the applied concentrations, except for azoxystrobin and metominostrobin. With 200 ${\mu}g\;L^{-1}$, its control value was 71.9%. When 1000 ${\mu}g\;m^{-3}$ of kresoxim-methyl in vapour phase was applied on 4 plants of cucumber in a vinyl chamber, 51.1% of control value on kresoxim-methyl-treated cucumber was showed 7 days after the application.

• Research in Plant Disease
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• v.8 no.2
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• pp.124-130
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• 2002

In 1998, a pathogen isolated from infected onions was identified as Aspergillus niger. At 3$0^{\circ}C$, A. niger AnYD-1 showed the best mycelial growth, spore germination, and high pathogenicity to onions. In spite of the weak inhibitory effect of flusilazole and hexaconazole on the mycelial growth on PDA, they showed the specific inhibitory activity against the formation of spores in the vapour phase. With flusilazole and hexaconazole, the effects of the solvent, the applied concentration and the incubating temperature on the activities inhibiting the spore formation were confirmed. Their inhibitory effect on the spore formation in vapour phase was excellent by solving them with dimethylsulfoxide and dimethylformamide among tested solvents, and applying them at high temperature such as 30~35$^{\circ}C$.

• Journal of Mechanical Science and Technology
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• v.14 no.2
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• pp.236-250
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• 2000

Compression ignition direct injection diesel engines employed a high pressure injection system have been developed as a measure to improve a fuel efficiency and reduce harmful emissions. In order to understand the effects of the pressure variation, many experimental works have been done, however there are many difficulties to get data in engine condition. This work gives numerical results for the high pressure effects on spray characteristics in wide or limited space with near walls. The gas phase is modelled by Eulerian continuum conservation equations of mass, momentum, energy and fuel vapour fraction. The liquid phase is modelled using the discrete droplet model approach in Lagrangian form and the drop behavior on a wall is calculated with a new droplet-wall interaction model based on the experiments observing individual drops. The droplet distributions, vapour fractions and gas flows are shown in various injection pressure cases. In free spray case which the injection spray has no wall impaction, the spray dispersion and vapour fraction increase and drop sizes decrease with increasing injection pressure. The same phenomena appears more clearly in wall impaction cases.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.307-311
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• 1999

The well-crystalline hydroxyapatite($Ca_{10}(PO_4)_6(OH)_2$ ; HAp) layer having a biocompatibility was successfully coated onto titanium substrate using a radio-frequency magnetron sputtering, and effects of sputtering gas and the thickness of HAp film on a crystal growth of the HAp layers were investigated. The deposition rate of the layer sputtered with water-vapour gas was slower than that of the layer sputtered with argon gas. The results of X-ray diffraction demonstrated that the about $0.8\mu\textrm{m}$ thick HAp film under water-vapour gas was an amorphous phase, the about $1.2\mu\textrm{m}$ thick film was (100) plane-oriented HAp, and the about $1.5\mu\textrm{m}$ thick film was (001)plane-oriented HAp. FT-IR analysis proved that hydroxyl group of the layer sputtered with argon gas was defected, but that of the layer sputtered with water-vapour gas was not defected. From these results, it was favorable to use water-vapour gas on the HAp coatings onto metal surface.

• Textile Coloration and Finishing
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• v.1 no.1
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• pp.7-18
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• 1989

The distinguishing characteristic of the glow discharge is that chemical reaction induced by partially ionized gases are limited only to the substrate surface. Most studies have been done on the plasma etching and polymerization. The graft polymerization in vapour phase by cold plasma has been rarely investigated. In this study the system of tub3ar reaction chamber with capacitively coupled electrode of alternative current of 60 Hz was employed for the graft polymerization. The graft polymerization of Acylic Acid(AA) onto the poly (ethylene terephthalate) (PET) was carried out by treatment of PET film and fabric by cold plasma (glow discharge of argon gas), followed by the supply of AA vapour. The graft yield was about 1 wt%. The surface property was determined by contact angle, the surface tension was evaluated by zisman’s plot and equation of surface tension mesurement. The results were as follows: 1. In order to obtain lower contact angle, it was effective to avoid the vicinity of electrodes for a setting position of substrate. 2. Contact angle affected on the monomer pressure and its duration of exposure to the acid vapour. 3. Polymer radical formation was influenced by the changes of the value of current density and plasma treatment time. 4. Total surface tension of plasma grafted PET film increased. With an increase in the carboxylic acid content, the dispersion force decreased, while, the polar force and hydrogen bonding force increased. 5. The contact angle decreased from $75^\circ$ to around $30^\circ$ by plasma grafting. There was no ageing effect on the contact angle after 4 months.