• Journal of the Korean Physical Society
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• v.73 no.11
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• pp.1698-1702
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• 2018

We simulate the light transmission through an extremely small nanoscale aperture having a 10 nm diameter punctured in a metal film positioned at the center of a plasmonic bull's eye grating. A considerable directive emission of transmitted light with a divergence angle of 5.7 degrees was observed at $10{\mu}m$ from the nanohole opening at the frequency of surface plasmon polariton excitation, an confirmed by measuring the distance dependent transmission amplitude. Observations of the electric field in cross-sectional, near-field, and far-field views near-field enhancement associated with the surface plasmon excitation, and the interference of the electric field light through the nanohole in the near-field region is responsible for such a considerable directive emission.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.3
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• pp.594-598
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• 2010

We studied on the field emission properties of double-walled carbon nanotubes (DWCNTs) coated with lead selenide (PbSe) nanoparticles. PbSe nanoparticles were uniformly attached on the surface of the DWCNTs by a simple chemical process. The PbSe-coated DWCNTs showed highly increased emission current density and enhanced emission stability over 20 h, compared with raw DWCNTs. We consider that the enhanced field emission properties of PbSe-coated DWCNTs were attributed to the increased field enhancement factor and lowered work function of the emitters.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.92-97
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• 2002

We establish a visible light emission from porous polycrystalline silicon nano structure(PPNS). The PPNS layer are formed on heavily doped n-type Si substrate. 2um thickness of undoped polycrystalline silicon deposited using LPCVD (Low Pressure Chemical Vapor Deposition) anodized in a HF: ethanol(=1:1) as functions of anodizing conditions. And then a PPNS layer thermally oxidized for 1 hr at $900 ^{\circ}C$. Subsequently, thin metal Au as a top electrode deposited onto the PPNS surface by E-beam evaporator and, in order to establish ohmic contact, an thermally evaporated Al was deposited on the back side of a Si-substrate. When the top electrode biased at +6V, the electron emission observed in a PPNS which caused by field-induces electron emission through the top metal. Among the PPNSs as functions of anodization conditions, the PPNS anodized at a current density of $10mA/cm^2$ for 20 sec has a lower turn-on voltage and a higher emission current. Furthermore, the behavior of electron emission is uniformly maintained.

• Journal of the Korean Wood Science and Technology
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• v.34 no.3
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• pp.30-37
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• 2006

The present study examined the formaldehyde (HCOH) emission characteristic of various wood-based panel used in interior design, and measured changes in formaldehyde emission when a number of VOC reduction methods were applied. Formaldehyde emission showed a clear tendency of increase with the rise of temperature, and the concentration of formaldehyde emitted changed according to the preprocessing condition before measuring. Formaldehyde emission from wood board after bake out treatment was lower than that of the control group. When specimens were coated with urethane, cashew, water, oil stain, they generally showed the decrease of formaldehyde emission, although varying according to finishing material, and when edge sealing was applied the decrease became significant. $TiO_2$ coating was more effective in decreasing formaldehyde under ultraviolet lamps than under ordinary lamps. When the irradiation of ultraviolet lamps gets longer, formaldehyde emission decreased.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.22.1-22.15
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• 2016

Background: Dietary manipulation is a common practice to mitigate gaseous emission from livestock production facilities, and the variation of fat level in the diet has shown great influence on ruminal volatile fatty acids (VFA) and enteric methane generation. The changes in dietary fat levels influence rumen chemistry that could modify manure nutrient composition along with odor and gaseous emissions from manure management facilities. Methods: A field experiment was carried out on beef cattle feedlots to investigate the effect of four levels of dietary fat concentrations (3 to 5.5 %) on the manure composition and gaseous emissions (methane-$CH_4$, nitrous oxide-$N_2O$, carbon dioxide-$CO_2$ and hydrogen sulfide-$H_2S$) from the feedlot pen surface. The experiment was carried out over a 5-month period from June to October during North Dakota's summer-fall climatic condition. Air and manure sampling was conducted five times at a 20-30 day intervals. Results: Overall, this research indicated that fat levels in diet have no or little effect on the nutrient composition of manure and gaseous emission from the pens with cattle fed with different diet. Though significant variation of gaseous emission and manure composition were observed between different sampling periods, no effect of high fat diet was observed on manure composition and gaseous emission. Conclusions: It can be concluded that addition of fat to animal diet may not have any impact on gaseous emission and manure compositions.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.483-488
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• 2002

Noise has become an environmental pollution that affects most peoples' health, comfort or general well being. there are many sources of noise, but one of them clearly dominates road traffic noise. It has traditionally been associated with engine and exhaust noise of vehicles. However the emission and propagation of noise from these sources were partly reduced, while at the same time the noise emission from the tire/road interaction on a relative scale became more and more prominent Generally, Portland cement concrete(PCC) pavements have the advantage of durability and superior surface friction when compared to most dense-graded asphalt. However, It is known that PCC pavements create more noise than asphaltic surfaces due to the noise from interaction of tire and pavement surface. Therefore, recent research has shown some new concrete pavement textures to be worth further examination. So in this paper, we considered the 9 types of low noise concrete pavements to evaluate tire/pavement noise.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.53-59
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• 2006

The paper highlights technical advances and introduces recent innovations such as smart curing laminating adhesives for flexible packaging with low migration rates of aromatic isocyanates and amines. Latent reactive one-part systems on the basis of surface deactivated solid isocyanates open up new dimensions for heat setting adhesives and waterborne PU dispersions. The new generation of Purmelt Micro Emission adhesives contains less than 0.1% of MDI monomer, thereby drastically reducing the emission of hazardous isocyanate vapors during processing and setting a significantly improved technical standard in occupational safety. Once again, polyurethane adhesives have demonstrated their unique ability to adapt to new process, product, safety and environmental requirements.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1198-1201
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• 2006

Carbon nanotubes (CNTs) have used as an electron field emitter of the field emission display (FED) due to their characteristics of high-electron emission, rapid response and low power consumption. However, to commercialize the FED with CNT emitter, some fundamental problems regarding life time and emission efficiency have to be solved. In this study, we investigated the metal coated CNT as a field emitter on which metal nanoparticles were coated by chemical modification. Metal nanoparticles, such as Ru, Pd, were synthesized by solution reduction method. The size of the metal nanoparticle has the range of 2 - 5 nm. Surface was modified chemically with the use of ionic surfactant which changed the surface charge of nanoparticles.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1210-1213
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• 2006

The effect of surface treatment on CNT cathodes used in field emission displays was investigated. A liquid method using a polymer-based organic solution and a mechanical method were applied. The liquid method, using PVA(polyvinyl alcohol) showed high potential compared to the mechanical adhesive taping and rolling method used in the fabrication of CNT cathodes for large-sized field emission displays with high emission uniformity and a low cost.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.648-653
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• 1996

Hydrogenated amorphous carbon(a-C:H) films are prepared by rf plasma CVD in a $CH_4$ source gas system diluted with Ar of $H_2$. The spectra of emissive and reactive species in the plasma are detected using in stiu optical emission spectroscopy. Inaddition, the relationship between the film properties which can be varied by the deposition parameters and the Raman spectra is studied. In the $CH_4/H_2$ gas system, the emission intensities of CH and $H \tau$ decrease and those of $H \alpha$, $H \beta$, $C_2$ and Ar increase with increasing $H_2$ concentration, The formation of $C_2$ and CH in the $CH_4/Ar/H_2$ gas system is greatly suppressed by hydrogen addition and the excess of hydrogen addition is found to form graphite structure. The $C_2$ formation in the gas phase enhances a-C:H film formation.