• 제목/요약/키워드: Surface Emission

검색결과 1,818건 처리시간 0.035초

Surface-Plasmon Assisted Transmission Through an Ultrasmall Nanohole of ~ 10 nm with a Bull's Eye Groove

  • Kim, Geon Woo;Ko, Jae-Hyeon;Park, Doo Jae;Choi, Seong Soo;Kim, Hyuntae;Choi, Soo Bong
    • Journal of the Korean Physical Society
    • /
    • 제73권11호
    • /
    • pp.1698-1702
    • /
    • 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.

셀렌화납 코팅을 통한 이중벽 탄소나노튜브의 전계방출특성 향상 (Enhanced field emission properties of double-walled carbon nanotubes coated with lead selenide nanoparticles)

  • 신동훈;이철진;최영민;김종웅
    • 전기학회논문지
    • /
    • 제59권3호
    • /
    • pp.594-598
    • /
    • 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.

다공질 실리콘을 이용한 전계 방출 소자

  • 주병권
    • 한국마이크로전자및패키징학회:학술대회논문집
    • /
    • 한국마이크로전자및패키징학회 2002년도 춘계 기술심포지움 논문집
    • /
    • pp.92-97
    • /
    • 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.

  • PDF

표면마감처리에 따른 목질보드의 포름알데히드 방산특성에 관한 연구 (Study on the Characteristics of Formaldehyde Emission from Wood-Based Panels Treated with Several Surface Finishing Materials)

  • 소원택;임진아
    • Journal of the Korean Wood Science and Technology
    • /
    • 제34권3호
    • /
    • pp.30-37
    • /
    • 2006
  • 본 연구는 각종 실내디자인에 이용되는 목질보드의 포름알데히드(HCOH) 방산 특성과 몇 가지 VOC 저감 방법에 대한 포름알데히드의 방산량 변화를 측정하였다. 포름알데히드 방산량은 온도가 증가함에 따라 뚜렷이 증가하는 경향을 보였고, 측정 전 처리조건에 따라 포름알데히드 방산량의 현저한 변화가 나타났다. bake-out 처리후의 목질보드의 포름알데히드 방산량은 대조구와 비교하여 감소함을 나타냈다. 시편에 urethane, cashew, water stain, oil stain coating을 했을 때 각 마감재료에 따라 포름알데히드 방산량의 차이가 확인되었으며, edge sealing 처리 후 두드러진 감소경향이 나타났다. $TiO_2$ coating은 일반광보다는 자외선 램프의 포름알데히드 저감효율이 좋았고, 자외선 램프의 조사시간이 길어지면 포름알데히드의 감소량도 증가하였다.

The effect of feeding high fat diet to beef cattle on manure composition and gaseous emission from a feedlot pen surface

  • Gautam, Dhan Prasad;Rahman, Shafiqur;Borhan, Md Saidul;Engel, Chanda
    • Journal of Animal Science and Technology
    • /
    • 제58권6호
    • /
    • pp.22.1-22.15
    • /
    • 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.

저소음용 콘크리트 포장의 소음평가 (Evaluation of the Noise Emission in Low Noise Concrete Pavements)

  • 문한영;하상욱;양은철
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
    • /
    • pp.483-488
    • /
    • 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.

  • PDF

Recent Advances and Trends in Reactive Polyurethane Adhesives

  • Krebs, Michael
    • 접착 및 계면
    • /
    • 제7권4호
    • /
    • pp.53-59
    • /
    • 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.

  • PDF

CNT Emitter Coated with Nanoparticles for FED Application

  • Kim, Jong-Ung;Lee, Jung-A;Ryu, Byong-Hwan;Kim, In-Ho;Moon, Hee-Sung;Kim, Jae-Myeong;Choi, Young-Min
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
    • /
    • pp.1198-1201
    • /
    • 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.

  • PDF

Characterization of Carbon Nanotube Cathodes with Surface Treatment by Polymer-Based Organic Materials

  • An, Young-Je;Lee, Ji-Eon;Kim, Kye-Sung;Cheon, Ko-Eun;Karim, Md. Anwarul;Cho, Young-Rae
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
    • /
    • pp.1210-1213
    • /
    • 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.

  • PDF

OPTICAL EMISSION SPECTROSCOPY OF Ch$_4$/Ar/H$_2$ GAS DISCHARGES IN RF PLASMA CVD OF HYDROGENATED AMORPHOUS CARBON FILMS

  • Lee, Sung-Soo;Osamu Takai
    • 한국표면공학회지
    • /
    • 제29권6호
    • /
    • pp.648-653
    • /
    • 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.

  • PDF