• Title/Summary/Keyword: Material Circumstance

Search Result 94, Processing Time 0.026 seconds

Sensing and Degradation Characteristics in the QCM Gas Sensor Coated with the PVC and PC (PVC 및 PC 혼합액을 코팅한 QCM 가스센서의 센싱 및 열화 특성)

  • Jang, Kyung-Uk;Kim, Myung-Ho;Lee, Joon-Ung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.04b
    • /
    • pp.176-179
    • /
    • 2000
  • In the recognition of the gases using the quartz crystal microbalance (QCM) coated with the film materials, it is important to obtain the recognition ability of gases, and the stability of film coated above the QCM. Especially, the thickness of film coated above the QCM is decreased according with the using circumstance and time of QCM gas sensor. Therefore, the sensing chararcteristics of film is changed with these. In this paper, we coated the lipid PC (Phosphatidyl Choline) materials varing with the blended amount of PVC(Poly Vinyl Chloride) and solution (Tetra Hydrofan:THF) above QCM to obtain the stability of lipid PC film. QCM gas sensors coated with film materials were measured the frequency change in the chamber of stationary gas sensing system injected 1-hexane, ethyl acetate, ethanol and benzene of $20{\mu}{\ell}$, respectively. We obtained the principal component analysis (PCA) from the frequency change due to the absorption of gas. Also, we measured the degradation characteristics of QCM gas sensor to show the properties of stability.

  • PDF

Preliminary Study on Traditional Earth Construction Technique use of Lime (석회를 활용한 전통 흙건축 기술에 관한 기초 연구)

  • Hwang, Hey zoo;Kang, Nam Yi
    • KIEAE Journal
    • /
    • v.10 no.2
    • /
    • pp.3-8
    • /
    • 2010
  • Many countermeasures are presented to make excessive earth circumstance pollution better in the earth. A lot of researches are in progress to lessen $CO_2$ among the industries exhausting it. The industries manufacturing cement are making many countermeasures. Many concernments on ECO-friendly materials, rather than cement, are increased, and researches are in progress to develop them. Lime, material mostly used before Portland cement appeared, attracts the Occident as well as the Orient. In the Occident, lime mortar was used in common, for maintaining and repairing cultural properties, too. This study is aimed at offering basic materials for the modern use of lime, ECO-friendly material. This study measured the change of intensity and weight with lime, sand, and earth, basic materials of Samhoimool. As a result, at the beginning, hydrated lime displayed its density late, but as time was gone, density was promoted continuously. In addition, density was promoted, when it was given heat at the beginning. If heat-generation reaction of quicklime and water was used, density was promoted at the beginning, but liquidity showed a drop.

Investigation of Oxidation Behavior of Alloy 617 under Air/Helium Environments at 950℃ (니켈기 합금 Alloy 617의 950℃ 대기/헬륨 분위기에서 산화거동 고찰)

  • Jung, Sujin;Lee, Gyeong-Geun;Kim, Dong-Jin
    • Corrosion Science and Technology
    • /
    • v.17 no.5
    • /
    • pp.218-224
    • /
    • 2018
  • Alloy 617 is a candidate Ni-based superalloy for intermediate heat exchanger (IHX) of a high-temperature gas reactor (VHTR), because of its good creep strength and corrosion resistance at high temperature. Small amount of impurities such as $H_2O$, $H_2$, CO and $CH_4$ are introduced inevitably in helium, as a coolant during operation of a VHTR. Reactions of material and impurities are accelerated with increase of temperature to $950^{\circ}C$ of operating temperature of a VHTR, leading to material corrosion aggravation. In this circumstance, high-temperature corrosion tests were performed at $950^{\circ}C$ in air and impure helium environments, up to 250 hours in this study. Oxidation rate of $950^{\circ}C$ in an air environment was higher than that of impure helium, explained by difference in outer oxide morphology and microstructure as a function of oxygen partial pressure. An equiaxed Cr-rich surface oxide layer was formed in an air environment, and a columnar Cr-rich oxide was formed in an impure helium environment.

Effect of Washing and Subsequent Heat Treatment on Water Repellency of Silk Fabric Treated with Fluorocarbon Resins

  • Park, Hyei-Ran;Lee, Mun-Cheul
    • Textile Coloration and Finishing
    • /
    • v.24 no.3
    • /
    • pp.173-179
    • /
    • 2012
  • Silk fabric treated with fluorocarbon resins (Asahi Guard AG-7005 and AG-E061) were washed and subsequently heat treated varying the washing cycles and the temperature. After the processing, the water and oil repellencies, and contact angle to water were evaluated. The water and oil repellencies decreased by the washing and recovered by following heat treatment. Also ESCA measurement was carried out to investigate the surface chemical composition of the treated fiber. The $F_1s$ intensity of the treated fabric decreased by the washing and recovered by the subsequent heat treatment. On the other hand, the $O_1s$ intensity increased by the washing and decreased by following heat treatment. From the results, it is clear that change of the water and oil repellencies of the silk fabric treated with fluorocarbon resin occurred by the washing and subsequent heat treatment. Considering a change of the water repellency of the silk fabric treated with fluorocarbon resin, it seems likely that the fluoroalkyl group of the fluorocarbon resin rotates from surface to inside of the fiber by the washing to adapt to the hydrophilic circumstance, and the orientation of the fluoroalkyl groups of the resin disturbed by the washing recovers the orientation to the fiber surface after the subsequent heat treatment.

A Study on the Changing Image of Glossy Materials after 1960s (1960년대 이후 광택소재 이미지 변화에 대한 연구)

  • 이유경;이희현
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.6 no.1
    • /
    • pp.64-72
    • /
    • 2004
  • The purpose of this paper is to investigate the changing fashion image of the glossy materials including metal, leather, vinyl, latex, plastic etc. from 1960's to the present. Glossy materials used in the second half of the 20th century showed a restricted image combined with a specific social circumstance. They expressed a reflection of young and future-oriented space period of 1960s. Many designers like Paco Rabanne and Andre Courreges were concerned with the fashion of space age and expressed that image with leather and synthetic materials including silver leather, metal chain armor, and plastic appeared as the keynote of fashion. In 1970's, glossy material was the symbol of avant-garde and rebellious attitude by the punk fashion. They maximized glamourous look of 1980s, and cyber look with an expectation for a new millenium of 1990s. On the other side, glossy materials seem to be used as a source of various inspiration of fashion designer in the 21st century. Also, some of the past images, for example space look and glamourous look, are revived in the 21 st century by the form of modified design.

  • PDF

A Study on Ken Ichiura's Research Activities of 'Dwellings' - Focused on 1930 to 1945 (시포건의 "주택" 분야 연구활동에 관한 연구 - 1930년부터 1945년까지를 중심으로 -)

  • Kim Jin-Mo
    • Journal of the Korean housing association
    • /
    • v.17 no.1
    • /
    • pp.9-17
    • /
    • 2006
  • In the modem society of Japan, specially before and after the World War II, one of the most important problem is socially to build housing of working classes. In those days, Ken Ichiura had been led the dwelling of modem Japanese architecture. He had worked in wide spheres of action like private residence, public housing, collective housing area and urban planning for about fifty years. But until now, because studies on public housing of Japan has been discussed only aspect of architectural design, there was almost no study about Ken Ichiura who acted in practical affairs. So this study aims to consider about the Ken Ichiura's research on dwelling and the relation with the then social circumstance. It was summarized as four details of Ken Ichiura's activities on Dwellings before the end of World War II. First, he proposed half-government-supervised system by economic reason on provision of dwellings. Second, he proposed dry construction system by material and structural reason on economic and stability supply. Third, he proposed standardization and industrialization by economic reason on industrialization form material to construction of industry. And the last, he also proposed standard plan and standard design by economical and mass production supply dwellings during the war.

A Study on Waterproofing and Anticorrosive Performance Evaluation of Polyurea Resin Waterproofing Membrane Coating of Velocity per Second Hardening (초속경화(初速硬化) 폴리우레아수지 도막방수재(途膜防水材)의 방수(防水)·방식(防蝕) 성능평가(性能評價)에 관한 연구(硏究))

  • Cho, Chan-Haeng;Kang, Hyo-Jin;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2003.11a
    • /
    • pp.91-95
    • /
    • 2003
  • There is a problem to be solved for improvement of durability and safety supervision. When you do the waterproofing and anticorrosive work of main concrete from the design stage, the material and method of construction need to be correctly applied to appropriate circumstance conditions. Epoxy have mostly been used for concrete water tank structure. Lately, lots of subjects on adaption of polyurea resin waterproofing and anticorrosive are under discussion. Then, we attempt to approach by evaluating and comparing every capabilities with another waterproofs in this study. Performance evaluation items include the adherence performance, the imprint of seal performance, temperature dependence performance, promotion weatherizing ability, inner chemical performance, drinking water eruptive performance. Through the experiment analysis, we found that the polyurea resin waterproofing membrane is dominantly superior to other waterproofs. According to this study, we suggest the polyurea resin waterproofing membrane as a new waterproofing material for concrete structure.

  • PDF

Degradation Properties in the QCM Gas Sensors Coated with the PEG Materials (PEG 물질을 도포한 QCM 가스센서의 열화특성)

  • Jang, Kyung-Uk;Kim, Myung-Ho;Lee, Won-Jae;Kim, Sang-Keol;Jung, Dong-Hoe;Lee, Joon-Ung;Lee, Ho-Sik;Kim, Tae-Wan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.05c
    • /
    • pp.218-222
    • /
    • 2002
  • In the recognition of the gases using the quartz crystal microbalance (QCM) coated with the PEG film materials, it is important to obtain the recognition ability of gases, and the stability of PEG film coated above the QCM. Especially, the thickness of PEG film coated above the QCM is decreased according with the using circumstance and time of QCM gas sensor. Therefore, the sensing characteristics of PEG film is changed with these. In this paper, we coated the PEG materials varing with the blended amount of PVC(Poly Vinyl Chloride) and chloroform above QCM to obtain the sensitive and the stability of PEG film. We measured the degradation characteristics of QCM gas sensor in the ethyle acetate 50[%] concentration to show the properties of stability.

  • PDF

A Study on Waterproofing Performance Evaluation of Polyurea Resin Waterproofing Membrane Coating of Velocity per Second Hardening (뿜칠형 초속경화 폴리우레아수지 도막방수재의 성능평가에 관한 연구)

  • Oh, Sang-Keun;Kim, Su-Ryun;Lee, Sung-Il
    • Journal of the Korea Institute of Building Construction
    • /
    • v.2 no.1
    • /
    • pp.131-138
    • /
    • 2002
  • There is a problem to be solved for improvement of durability and safety supervision. When you do the waterproofing work of main concrete from the design stage, the material and method of construction need to be correctly applied to appropriate circumstance conditions. Epoxy have mostly been used for concrete water tank structure. Lately, lots of subjects on adaption of polyurea resin waterproofing and anticorrosive are under discussion. Then, we attempt to approach by evaluating and comparing every capabilities with another waterproofs in this study. Performance evaluation items include the adherence performance, the imprint of seal performance, temperature dependence performance, promotion weatherizing ability, Inner chemical performance. drinking water eruptive performance. Through the experiment analysis, we found that the polyurea resin waterproofing membrane is dominantly superior to other waterproofs. According to this study, we suggest the polyurea resin waterproofing membrane as a new waterproofing material for concrete structure.

A Study on Waterproofing and Anticorrosive Performance Evaluation of Polyurea Resin Waterproofing Membrane Coating of Velocity per Second Hardening (초속경화 폴리우레아수지 도막방수재의 방수.방식 성능평가에 관한 연구)

  • 조찬행;강효진;오상근
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2003.05a
    • /
    • pp.91-95
    • /
    • 2003
  • There is a problem to be solved for improvement of durability and safety supervision. When you do the waterproofing and anticorrosive work of main concrete from the design stage, the material and method of construction need to be correctly applied to appropriate circumstance conditions. Epoxy have mostly been used for concrete water tank structure. Lately, lots of subjects on adaption of polyurea resin waterproofing and anticorrosive are under discussion. Then, we attempt to approach by evaluating and comparing every capabilities with another waterproofs in this study. Performance evaluation items include the adherence performance. the imprint of seal performance, temperature dependence performance. promotion westernizing ability, inner chemical performance. drinking water eruptive performance. Through the experiment analysis, we found that the polyurea resin waterproofing membrane is dominantly superior to other waterproofs. According to this study, we suggest the polyurea resin waterproofing membrane as a new waterproofing material for concrete structure.

  • PDF