• 제목/요약/키워드: dry deposition

검색결과 363건 처리시간 0.042초

증착방법에 따른 DLC 막의 마찰-마모 특성평가 (Characterization of Tribological Properties of DLC Films Prepared by Different Deposition Method)

  • 오윤석
    • 한국세라믹학회지
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    • 제46권5호
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    • pp.497-504
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    • 2009
  • DLC is considered as the candidate material for application of moving parts in automotive components relatively in high pressure and temperature operating conditions for its high hardness with self lubrication and chemical inertness. Different deposition method such as arc plating, ion gun plating and PECVD were used for comparing mechanical and tribological properties of each DLCs deposited on stainless steel with 1 um thick respectively. Among these 3 types of DLCs, the arc plated DLC film showed highest value for wear resistance in dry condition. From the results of analysis for physical properties of DLC films, it seems that the adhesion force and crack initiation modes were more important factors than intrinsic mechanical properties such as hardness, elastic modulus and/or roughness to the wear resistance of DLC films. Raman spectroscopy was used for understanding chemical bonding natures of each type of DLC films. Typical D and G peaks were identified based on the deposition method. Hardness of the coating layers were identified by nanoindentation method and the adhesions were checked by scratch method.

Verification of a Dynamic Compartment Model for the Tritium Behavior in the Plants After Short HTO Release Using a BIOMOVS II Scenario

  • Park, Heui-Joo;Kang, Hee-Suk;Lee, Hansoo
    • Nuclear Engineering and Technology
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    • 제35권2호
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    • pp.171-177
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    • 2003
  • A dynamic compartment model was required for the prediction of radiological consequences of the tritiated vapor released from the nuclear facility after an accident. A computer code, ECOREA-T, was developed by incorporating the unit models for the evaluation of tritium behavior in the environment. Dry deposition of tritiated vapor from the atmosphere to the soil was calculated using a deposition velocity. Transport of tritium from the atmosphere to the plant was calculated using a specific activity model, and the result was compared with the Belot's analytic solution. Root uptake of tritiated water from the soil and formation of OBT from T were considered in the model. The ECOREA-T code was verified by comparing the results from the other computer codes using a scenario developed through BIOMOVS II study. The results showed good agreements.

대기오염 총침착물의 채취방법 표준화 개발에 관한 연구 -여과식 채취방법을 통한 총침착물의 공간분포 특성- (A Study on the Development of Standard Method of Total Deposition Sampling in Air Pollutants - Spatial Distribution of Total Deposition by the Filtration-Sampling Method -)

  • 박정호;조인철;김찬훈;서정민
    • 한국환경과학회지
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    • 제11권6호
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    • pp.489-496
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    • 2002
  • The purpose of this study was to investigate spatial distributions of total deposition. A total number 79 samples were collected at 17 sampling sites from September 1999 to January 2000. Total (=wet+dry) atmospheric depositions were collected by filtered deposition sampler at sampling site (the Western Part of Kyongsangnam Province). In addition, the deposition of soluble and insoluble fraction was also investigated to find a suitable simplified collection method for a long-term monitoring of total deposition. The total depositions were measured soluble amount(mm/month), insoluble amount(kg/km$^2$/month), pH, conductivity(E.C.) and eight ionic components. The spatial distribution of deposition flux was to estimated by using a kringing analysis. The 17 sites mean fluxes of water soluble ionic components; SO$_4$$\^$2-/, Cl$\^$-/, NO$_3$$\^$-/, Na$\^$+/, NH$_4$$\^$+/, K$\^$+/, Mg$\^$2+/, Ca$\^$2+/ were 100.7∼315.6kg/km$^2$/month, 30.1∼234.3kg/km$^2$/month, 64.4∼ 139.4kg/km$^2$/month, 7.5∼68.3kg/km$^2$/month, 10.7∼48.7kg/km$^2$/month, 5.6∼27.9kg/km$^2$/month, 4.5∼17.5kg/km$^2$/month, 27.6∼81.7kg/km$^2$/month, respectively.

관거 내 고형물 퇴적량 산정식 개발 (Development of Estimation Equations for Solid Deposition in Sewer Systems)

  • 이재수
    • 한국수자원학회논문집
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    • 제40권5호
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    • pp.409-418
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    • 2007
  • 건기에 합류식 관거 내에 퇴적된 고형물은 우기에 재부상하여 초기부하(first-flush) 현상의 주된 원인이 되고 있으며, 이러한 고형물의 퇴적으로 인해 관거 내 통수능이 감소하여 도시지역의 국지적인 내수침수가 발생하고 있다. 이와 같은 문제를 해결하기 위해서는 장기간에 걸친 관거 내 고형물 퇴적량을 관측할 필요가 있으나 많은 비용과 노력이 수반되어야 한다. 본 논문에서는 MOUSE 모형에 의해 산정된 결과로부터 고형물 퇴적량을 산정하기 위한 회귀식의 개발 및 적용성을 검토하였다. 분석 결과 관거 내 퇴적고형물의 관측 자료가 구비되어 있지 않아 실질적으로 비교하기는 곤란하지만 MOUSE 모형이나 EPA(미환경보호청)에서 제시한 공식을 이용하여 산정한 결과와 비교해 볼 때 본 연구에서 개발된 산정식은 적용성이 있음을 보여주고 있다.

Wood and Leaf Litter Decomposition and Nutrient Release from Tectona grandis Linn. f. in a Tropical Dry Deciduous Forest of Rajasthan, Western India

  • Kumar, J.I. Nirmal;Sajish, P.R.;Kumar, Rita.N.;Bhoi, Rohit Kumar
    • Journal of Forest and Environmental Science
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    • 제26권1호
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    • pp.17-23
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    • 2010
  • The present study was conducted to quantify wood and leaf litter decomposition and nutrient release of a dominant tree species, Tectona grandis Linn. F. in a tropical dry deciduous forest of Rajasthan, Western India. The mean relative decomposition rate was maximum in the wet summer and minimum during dry summer. Rainfall and its associated variables exhibited greater control over litter decomposition than temperature. The concentrations of N and P increased in decomposing litter with increasing retrieval days. Mass loss was negatively correlated with N and P concentrations. The monthly weight loss was significantly correlated (P < 0.05) with soil moisture and rainfall in both wood and leaf litter. Tectona grandis was found to be most suitable tree species for plantation programmes in dry tropical regions as it has high litter deposition and decomposition rates and thus it has advantages in degraded soil restoration and sustainable land management.