• Title/Summary/Keyword: Atmosphere control

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A Study on the Corrosion Properties of Reinforcing bar and Performance Evaluation of Repair Material and Method for Reinforced Concrete Structure by Exposure Experiment under the Coastal and Normal Atmosphere Environment (해양 및 일반대기환경의 폭로실험에 의한 철근콘크리트구조물 보수재료.공법의 성능평가 및 철근의 부식특성에 관한 연구)

  • Nam Jeong-Soo;Roh Kyung-Min;Shin Seung-Bong;Kim Young-Sun;kim Gyu-Yong;Kim Moo-Han
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.05a
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    • pp.167-171
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    • 2006
  • In this study, for the establishment of the performance evaluation methods of repair material and method for reinforced concrete structure and the quality control standards of durability recovery method, the quantitative exposure data by exposure experiment under the coastal and normal atmosphere environment is accumulated and analyzed. Investigating and evaluating the result of exposure experiment during 30 months of exposure age under the coastal and normal atmosphere environment, carbonation depth and chlorideion penetration depth very little penetrated than cover depth. It seems reasonable to conclude that main cause of corrosion of reinforcing bar are inner chloride-ion and macro cell from the result of corrosion area and corrosion velocity. Accordingly, it is considered that fundamental data on the performance evaluation and quality control standards of repair material and method could be presented through continuous exposure test in the future.

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Processing and Quality Control of Big Data from Korean SPAR (Soil-Plant-Atmosphere-Research) System (한국형 SPAR(Soil-Plant-Atmosphere-Research) 시스템에서 대용량 관측 자료의 처리 및 품질관리)

  • Sang, Wan-Gyu;Kim, Jun-Hwan;Shin, Pyong;Baek, Jae-Kyeong;Seo, Myung-Chul
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.22 no.4
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    • pp.340-345
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    • 2020
  • In this study, we developed the quality control and assurance method of measurement data of SPAR (Soil-Plant-Atmosphere-Research) system, a climate change research facility, for the first time. It was found that the precise processing of CO2 flux data among many observations were sig nificantly important to increase the accuracy of canopy photosynthesis measurements in the SPAR system. The collected raw CO2 flux data should first be removed error and missing data and then replaced with estimated data according to photosynthetic lig ht response curve model. Comparing the correlation between cumulative net assimilation and soybean biomass, the quality control and assurance of the raw CO2 flux data showed an improved effect on canopy photosynthesis evaluation by increasing the coefficient of determination (R2) and lowering the root mean square error (RMSE). These data processing methods are expected to be usefully applied to the development of crop growth model using SPAR system.

Preparation and Microwave Absorbing Characteristics of Ni-Zn Ferrite Composite (복합 Ni-Zn Ferrite의 제조 및 전파흡수특성)

  • 최경구;오재희;김성수;김재묵
    • Journal of the Korean Ceramic Society
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    • v.29 no.7
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    • pp.505-510
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    • 1992
  • The influence of excess iron content (x) and reaction atmosphere on permittivity, permeability and microwave absorbing properties has been investigated in composite specimens embeded with (Ni0.4Zn0.6O)1-x(Fe2O3)1+x powders. A nitrogen atmosphere used for the reaction of the ferrite with excess iron composition (x>0) enhances spinel formation, and thereby increases both the magnetic and the dielectric loss of the ferrite composite. We also investigated the relation between the electromagnetic constants and the absorbing properites using impedance-matching solution maps for zero reflection. It is suggested that a superior microwave absorber can be fabricated through atmosphere and excess iron control during the powder process.

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Studies on AlF3-(Mg+Sr+Ba)F2-P2O5 Glasses II. Effect of MgF2 Contents (AlF3-(Mg+Sr+Ba)F2-P2O5계 유리에 관한 연구 제2보 : MgF2의 영향)

  • 김정은;이종근
    • Journal of the Korean Ceramic Society
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    • v.24 no.3
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    • pp.277-281
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    • 1987
  • The various contents of MgF2 from 0 to 12.5wt% are studied in the AlF3-(Mg+Sr+Ba)F2-P2O5 system for the effects of various properties in glasses and the atmosphere of melting was controlled by N2 and Ar gas respectively. Density, refractive index, infrared transmission, thermal conductivity and thermal expansion coefficient of glasses are determined. Density, refractive index and thermal conductivity are decreased, micro-hardness and thermal expansion coefficient are increased according to the increasing of MgF2 contents. Infrared transmittance decreases with increasing the MgF2 contents and it slightly dropped by air than N2 and Ar atmosphere. Other properties are not influenced by atmosphere control.

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The study on Reactor Parameters of Atmosphere Plasma Power Supply (대기압 플라즈마 전원장치의 반응기 파라메터에 관한 연구)

  • Lee, Woo-Cheol;Lee, Taeck-Ki
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.6
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    • pp.59-65
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    • 2012
  • This paper presents a digital control solution which can extract the reactor parameters in atmosphere plasma power supply. The critical issue of the atmosphere plasma power supply is a impedance matching. For the impedance matching, the reactor parameters should be known, but the parameters depend on the reactors. Therefore, the reactor parameters have to measure for the impedance matching. The proposed method is performed by detection of phase difference between inverter voltage and current, and extraction of impedance through active, reactive power.

Crystal Growth of $LiTaO_3$ and the Effect pf Crucible Type and Atmosphere ($LiTaO_3$ 단결정 성장과 용기 및 분위기의 영향)

  • 박승익;채승욱;김정돈;주기태;정수진
    • Journal of the Korean Ceramic Society
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    • v.31 no.1
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    • pp.39-46
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    • 1994
  • LiTaO3 single crystals were growth without cracking using Pt-Rh crucible and Ir crucible. The starting composition to get the melt of congruent melting composition, which has been dependent upon the experimental procedure, was taken after fixing the total growing process by the result of preliminary experiments. The Rh contamination from the Pt-Rh crucible was to be neglected if the crystal had been grown under inert atmosphere, which resulted in the crystal color being slightly yellow. This color was decolored after 24 hour's annealing at 1200℃ under air atmosphere. The optimum conditions for the crystal growing and the diameter control were so dependent upon the crucible material in spite of using the crucible of the same size. The liquid-solid interface of LiTaO3 crystal of 1" diameter has been flat if the rotation speed was 45rpm.

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Monitoring of air Pollution on the Premises of the Factory Sharrcem - L.L.C

  • Luzha, Ibush;Shabani, Milazim;Baftiu, Naim
    • International Journal of Computer Science & Network Security
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    • v.22 no.10
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    • pp.214-222
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    • 2022
  • In these proceedings, we will address the problem of air pollution on the premises of the Cement factory SHARRCEM L.L.C. in Hani Elezit in the Republic of Kosovo respectively around the clinker cooler, rotary kiln, and raw material mill. By air pollution, we mean the introduction of chemicals, particles, or other harmful materials into the atmosphere which in one way or another causing damage to the development of plants and organisms. Air pollution occurs when certain substances are released into the air, which depending on the quantitative level, can be harmful to human health, animals, and the environment in general. The analysis of air shows the influence of the extractive and processing industry on the chemical composition of air. Parameters analyzed though under control such as the case of carbon dioxide, due to the increasing production capacity of cement, the production of hundreds of thousands of cubic meters of CO2 gas made CO2 production a concern. With the purchase of the latest technology by the SHARCEM Factory in Hani Elezit, the amount of air pollution has been reduced and the allowed parameters of environmental pollution have been kept under control. Air pollutants are introduced into the atmosphere from various sources which change the composition of the atmosphere and affect the biotic environment.The concentration of air pollutants depends not only on the quantities that are emitted from the sources of air pollution but also on the ability of the atmosphere to absorb or disperse these emissions. Sources of air pollutants include vehicles, industry, indoor sources, and natural resources. There are some natural pollutants, such as natural fog, particles from volcanic eruptions, pollen grains, bacteria, and so on.

Properties of Ag Thin Films Deposited in Oxygen Atmosphere Using in- line Magnetron Sputter System (In-line 마그네트론 스퍼터 장치를 사용하여 산소 분위기에서 제작한 Ag 박막의 특성)

  • Ku, Dae-Young;Kim, Won-Mok;Cho, Sang-Moo;Hwang, Man-Soo;Lee, In-Kyu;Cheong, Byung-Ki;Lee, Taek-Sung;Lee, Kyeong-Seok;Cho, Sung-Hun
    • Korean Journal of Materials Research
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    • v.12 no.8
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    • pp.661-668
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    • 2002
  • A study was made to examine the electrical, compositional, structural and morphological properties of Ag thin films deposited by DC magnetron sputtering in $O_2$ atmosphere with deposition temperature from room temperature to 15$0^{\circ}C$ using in-line sputter system. The Ag films deposited at temperature above $100^{\circ}C$ in oxygen atmosphere gave a similar specific resistivity to and even lower oxygen content than those deposited using pure Ar sputter gas The Ag films deposited with pure Ar gas was mainly composed of crystallites with [111] preferred orientation, while, for those deposited in oxygen atmosphere, more than 50% of the volume was composed of crystallites with [100] orientation. The difference in the micro structure did not cause any difference in the specific resistivity of Ag films. The results showed that the transparent conducting oxide films and the Ag films could be processed sequentially in the same deposition chamber with careful control of deposition temperature, which might result in a cost reduction for constructing the large scale in-line deposition system.

Thermal Decomposition of Tetrakis(ethylmethylamido) Titanium for Chemical Vapor Deposition of Titanium Nitride

  • Kim, Seong-Jae;Kim, Bo-Hye;Woo, Hee-Gweon;Kim, Su-Kyung;Kim, Do-Heyoung
    • Bulletin of the Korean Chemical Society
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    • v.27 no.2
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    • pp.219-223
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    • 2006
  • The thermal decomposition of tetrakis(ethylmethylamido) titanium (TEMAT) has been investigated in Ar and $H_2$ gas atmospheres at gas temperatures of 100-400 ${^{\circ}C}$ by using Fourier Transform infrared spectroscopy (FTIR) as a fundamental study for the chemical vapor deposition (CVD) of titanium nitride (TiN) thin film. The activation energy for the decomposition of TEMAT was estimated to be 10.92 kcal/mol and the reaction order was determined to be the first order. The decomposition behavior of TEMAT was affected by ambient gases. TEMAT was decomposed into the intermediate forms of imine (C=N) compounds in Ar and $H_2$ atmosphere, but additional nitrile (RC$\equiv$N) compound was observed only in $H_2$ atmosphere. The decomposition rate of TEMAT under $H_2$ atmosphere was slower than that in Ar atmosphere, which resulted in the extension of the regime of the surface reaction control in the CVD TiN process.

Packaging Conditions of Peeled Onions to Preserve there Freshness (박피양파의 선도유지를 위한 포장조건)

  • 정순경;조성환
    • Food Science and Preservation
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    • v.4 no.3
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    • pp.259-264
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    • 1997
  • To improve freshness of onion(Allium cepa), it was packed with various packaging films and stored at 5$^{\circ}C$ until 52 days. During the storage, internal gas composition, weight loss, spout ratio, decay ratio, surface color were determined. The used packaging films are two-perforated LDPE (control), LDPE, CPP/OPP/PE, Nylon/PE and Ag-zirconium filled LDPE. Onions were prepared by peeling or dipping in GFSE(grape fruit seed extract) and packed under vacuum or atmosphere with the selective films. Anaerobic condition was shown in the Nylon/PE package after 4 days and, thus weight loss, sprout ratio and color were considerably poor. All onions in the vacuum package after 15 days were spouted. Onions in CPP/OPP/PE and functional film(Ag-zirconium filled LDPE) package showed aerobic respiration until 52 days. Thus, the quality of onions in these packages was superior to the control.

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