RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 음성지원유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • Study on a Fixed Bed Gasification of Polyurethane SRF from Electronic Waste

        ( Won-seok Yang ),( Jang-soo Lee ),( Se-won Park ),( Jae-jun Kang ),( Tanvir Alam ),( Yong-chil Seo ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 3RINCs초록집 Vol.2015 No.-

        With expanding economic growth, the consumption and changing period of electronics products have increased rapidly last a couple of decades in Korea. A refrigerator generally contains 10% of polyurethane. Since the amount of used refrigerators collected at recycling facilities of E-wastes has increased since 2007, the generation of polyurethane waste has also increased. Polyurethane recycling technologies have been investigated such as polyol production and sound-absorbing materials, which are not commercialized yet due to high cost of the technology. However many kinds of plastic wastes are being used as solid refuse fuel (SRF) like RDF, so polyurethane in E-waste could be utilized as valuable fuels, since it has higher heating values and contains low sulfur, low chlorine, and less hazardous substances. In this study an attempt to fabricate pellet type of SRF from polyurethane waste was conducted to use them as fuels even though it was not easy to make pellet, because characteristics of polyurethane were high volume and low density. Recently, Korean Association of Electronics Environment (KAEE) is producing pelletized SRF. The basic characteristics of polyurethane such as elemental composition, thermal properties and proximate analysis were carried out to assess whether they could be used as fuels or not. Using a fixed bed test reactor, gasification experiments were also conducted at the temperature of 1,000 ℃ by measuring exhaust gas compositions and gas pollutants.

      • An experimental study on the characteristics of polyurethane-mixed coarse aggregates by large-scale triaxial test

        Lee, Su Hyung,Lee, Sung Jin,Park, Jeung Geun,Choi, Yeong-Tae Elsevier 2017 Construction & building materials Vol.145 No.-

        <P><B>Abstract</B></P> <P>The two main functions of ballast are train-load distribution and track-water drainage. Repeated train passage subjects ballast aggregates to abrasion and, eventually, breakage. Mixing of bonding materials such as polyurethane into aggregates can effectively mitigate ballast degradation. In the present study, large-scale triaxial tests were carried out to investigate the characteristics of polyurethane-mixed ballast materials. The stiffness and strength of the materials could be predicted in terms of the polyurethane contents, and the linear relationships could be established. According to those relationships, the performance of polyurethane-mixed aggregates as enhanced railway ballast materials can be simply but reasonably estimated.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper focuses on the behavior of ballast aggregates induced by train loading. To improve performance of the ballast, polyurethane is added. The moduli and strength are investigated according to content of polyurethane. </LI> <LI> A large scale triaxial testing equipment was applied to evaluate the behavior of ballast accurately. The large triaxial tests lead to the correlation between polyurethane content and stiffness of polyurethane mixed ballast. The large scale triaxial tests provide with predictive model for strength as well. </LI> <LI> These simple models are believed to help design the ballast with polyurethane without expensive and cumbersome testing. </LI> </UL> </P>

      • KCI등재

        인계 화합물의 첨가에 의한 폴리우레탄의 난연성

        정영진,Chung, Yeong-Jin 한국화재소방학회 2006 한국화재소방학회논문지 Vol.20 No.4

        폴리우레탄에 인계 화합물을 첨가하여 폴리우레탄폼을 제조하였으며, 인계 화합물이 제조된 폴리우레탄폼의 기계적 물성과 난연성에 미치는 영향에 대하여 고찰하였다. 폴리우레탄과 인계 난연제인 Tri(chloroisopropyl) phosphate(TCPP), Triethyl phosphate(TEP), Trimethyl phosphate(TMP) 각각을 약 $90^{\circ}C$에서 혼합시켜 혼합물로부터 제조된 경질 폴리우레탄폼에 대한 여러 실험을 통하여 기계적 물성뿐만 아니라 난연 효과도 상당히 향상됨을 확인하였다. Cone calorimeter를 이용하여 열방출율(heat release rate, HRR)을 측정하여 난연 첨가제의 함량에 따른 재료별 난연 특성을 평가하였다. 그리고 Scanning Electron Microscope(SEM)을 사용하여 난연제를 첨가하여 만든 폴리우레탄폼의 morphology를 관찰한 결과 순수한 폼과 마찬가지로 매우 균일한 형태의 cell 분포를 가짐을 확인하였다. Polyurethane(PU) was mixtured by the treatment with flame retardants such as Tri(chloroisopropyl) phosphate(TCPP), Triethyl phosphate(TEP) and Trimethyl phosphate(TMP) at about $90^{\circ}C$. Rigid polyurethane foam was produced using the mixured products as flame retardants. The mechanical property and flammability of rigid polyurethane was investigated. The mixtured polyurethane shows reduced flammability over virgin polyurethane. Mechanical strength of mixtured polyurethane also shows as high as that of virgin polyurethane. In order to evaluate flame retardant properties of the mixtured polyurethane foams, heat release rate(HRR) of the foam was measured by cone calorimeter. Scanning electron micrograph of mixtured PU shows uniform cell morphology as virgin PU.

      • KCI등재후보

        톨루엔 디이소시아네이트 폭로 근로자들의 작업방법에 따른 대사물질의 비교 및 면역능에 관한 연구

        이수일,조병만,황인경,이철호,박정래 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.3

        Following recent advanced industrialization, the amount of polyurethane to use as thermal insulating materials, upholstery, mattresses and packing materials in automotive and furniture industry is increasing world-widely, and the number of polyurethane-producing worker will be increased. Because the numerous organic solvents are used in polyurethane-producing factory, the workers in this work site is exposed to many organic solvents. Of the organic solvents, Toluene Diisocyanate(TDI) has many hazardous effects to human. The effects of TDI on human are the irritation to respiratory mucosa and gastrointestinal symptoms. Conjunctival irritation, dermal inflammation (redness, pain, vesicular formation) and gastrointestinal symptom(nausea, vomiting. abdominal pain) are reported just after short-term exposure of TDI. TDI is known to give rise to bronchial asthma, as the immune disorder. And because of strongly volatile characteristics of TDI, it is suggested as a more injurious material to human health, especially human immune system, than other organic solvents. Bronchial asthma inducing mechanism of TDI is not clearly known, but on the analogy of TDI induced symptoms and recent studies, early-onset asthma is type I hypersensitivity reaction mediated by immunoglobulin E(IgE), and late-onset asthma is maybe type III hypersensitivity reaction by circulating IgG. And we know that the complicated human immune function is likely to move in such that mechanisms, there are not studies on immune indices evaluating the bronchial asthma-related immune function. The evaluation of change patterns of humoral immunity including IgE and IgG and cellular immunity including T-helper cell. T-suppressor cell and T-cytotoxic cell will be helpful to evaluate exposure degrees and prognosis in TDI exposed workers. Because TDA(toluene diamine) as a biological exposure index of TDI becomes the focus of interest, we know that a study on the correlation between urinary TDA and air TDI and immunological indices will make a contribution to biological effect monitoring indicies. We examined human immunity indicators such as WBC, %Lymph (percentile of Lymphocyte in WBC), %T-cell(percentile of T-lymphocyte in total lymphocyte). CD4, CD8, C3, C4, IgA, IgG, IgM, IgE in peripheral blood to evaluate the health hazard of the TDI-exposed workers. And we examined TDA to evaluate correlation between exposure and effect. Total 90 subjects was selected, 45 workers who worked in the polyurethane-producing factories as an exposed group, and 45 cases who were office workers(10 cases), other blue collors(27 cases), and medical college students(8 cases) as a control group. And the results were as follows; 1. The logarithm of IgE-Log10(IgE)±SD-in peripheral blood of a exposed group was significantly higher than a control group, 2.22 ±0.62 in case group compared with 1.98±0.53 in control group. (p<0.05) 2. IgA and IgM in the polyurethane-producing workers were 261.02±83.12㎎/㎗, 151.97 ±59.64 ㎎/㎗, respectively, and 292.77±100.45, 179.17±100.78 in control group. IgA and IgM was slightly lower in polyurethane-producing group than control.(p>0.05) 3. WBC, %Lymph. %T-cell, C3, C4, CD4, CD8, CD4/CD8 ratio and IgG in case group were 6.391.1 ea/㎖, 37.53 %, 59.54 %, 76.68 ㎎/㎗, 0.76×10(9) ea/L, 0.63×10(9) ea/L, 1.39, and 1606.29 ㎎/㎗, respectively, and 6,974.7 ea/㎖, 35.12 %, 59.64 %, 71.95 ㎎/㎗, 33.94 ㎎/㎗, 0.80×10(9) ea/L, 0.61×10(9) ea/L, 1.39, and 1581.51 ㎎/㎗ in control group. There was no statistical significance between two groups.(p>0.05) 4. In the comparison of each other companies, average of individual urinary TDA in polyurethane paint manufacturing companies is higher than that of polyurethane sponge foaming companies. And, the concentration of 2.6-TDA which is a metabolite of well-vaporized 2.6-TDI is higher than that of 2.4-TDA in the polyurethane sponge foaming companies. But, the concentration of 2.4-TDA which is a metabolite of illvaporized but well skin-absorbed 2.4-TDI is higher in polyurethane paint manufactures. 5. There were no statistical significance in the correlations between individual urinary TDA and immunologic indices.

      • KCI등재

        양이온성 폴리우레탄-아크릴레이트계 보류향상제의 합성 및 특성

        김두원 ( Doo Won Kim ),윤두수 ( Doo Soo Yoon ),김선 ( Sun Kim ),한철 ( Chul Han ),홍완해 ( Wan Hae Hong ),김정규 ( Jung Gyu Kim ) 한국고무학회 2004 엘라스토머 및 콤포지트 Vol.39 No.3

        Polyurethane prepolymer에 2-hydroxyethlmethacylate(HEMA)와 acrylamide(AA)를 반응시켜 두 가지 타입의 polyurethane-ac틴ate 중합체들을 합성하였다. 합성된 중합체들을 소량의benzyl chloride와 증류수를 이용하여 수용성 중합체인 폴리우레탄-아크릴레이트계 양이온성 보류향상제를 제조하였다. 이렇게 두 가지 형태로 제조된 중합체에 대하여 보류향상제로서 중요한 특성인 보류. 탈수특성 및 비압축강도 등의 물성들을 다양한 방법으로 고찰하였다. 합성된 폴리우레탄-아크릴레이트계 양이온성 보류향상제는 rpm에 따라 큰 변화 없이 70% 내외의 보류도를 유지하였으며, 합성한 보류향상제의 첨가로 인한 화학적 산소 요구량(COD)의 경우는 미첨가시의 COD보다 상당히 낮은 값이 관찰되었다. 탈수량의 경우 무처리한 펄프보다 보류향상제의 첨가 시에 탈수성이 향상되었으며, 보류향상제의 첨가 시 비압축강도가 소량 증가되었고. PH-HEMA가 PU-AA보다 우수한 강도를 나타내었다. Two types of polyurethane-acrylate polymer were synthesized by reaction of 2-hydroxyethyl methacrylate(HEMA), acrylamide(AA), and polyurethane prepolymer. Water-soluble cationic polyurethane/ acrylate retention aids were prepared by using polyurethane-acrylate, benzyl chloride and distilled water. The retention, drainage and strength properties of the retention aids were investigated. The retention of cationic polyurethane/acrylate type retention aids maintained around 70 % regardless of rpm. COD value of white water was much reduced by adding the retention aids to it. Drainage property was also improved by addition of the retention aids. In addition, specific compression strength of the paper was improved a little by addition of the retention aids. PU-HEMA type showed better performance than PU-AA in terms of compression strength of the paper.

      • KCI등재

        스프레이형 폴리우레탄폼 시공중 발생하는 발포제의 화재 위험성에 관한 연구

        최유정(Yoo-Jeong Choi),최수길(Su-Gil Choi),김시국(Si-Kuk Kim) 한국화재소방학회 2023 한국화재소방학회논문지 Vol.37 No.6

        This study investigates the risk of fire explosion caused by the presence of combustible gas in the propellant of spray-type polyurethane foam and the ammonia gas generated during the curing of polyurethane foam. Analysis of domestic fire cases confirmed that when construction work using polyurethane foam spray and fire handling were conducted simultaneously, fire accidents repeatedly occurred because the welding sparks acted as an ignition source on the surface of the polyurethane foam. Experiments confirmed the possibility of fire explosion owing to the presence of flammable substances in the polyurethane foam and the combustible gas in the propellant. The production of ammonia gas increased during the polyurethane-foam-curing stage, and B3 was more dangerous than B1. 본 논문은 스프레이형 폴리우레탄폼의 추진제에 들어있는 가연성 가스와 폴리우레탄폼 경화 시 발생하는 암모니아 가스로 인한 화재폭발의 위험성을 알아보기 위한 연구이다. 국내 화재사례를 분석한 결과 폴리우레탄폼 스프레이폼을 이용한 시공작업과 화기 취급을 동시에 진행하여 가연성가스가 실내에 체류되며 용접불티 등이 폴리우레탄폼 표면에 점화원으로 작용해 화재사고가 반복적으로 일어난 것을 확인하였다. 이에 따라 난연 등급별 스프레이형 폴리우레탄폼을 이용하여 폴리우레탄폼 점화실험장치를 이용한 착화실험과 스프레이형 폴리우레탄폼의 실화재 실험을 진행하였다. 실험결과 폴리우레탄폼 내부에 함유된 인화성 물질의 양과 추진체에 들어 있는 가연성 가스에 의해 화재폭발 가능성을 확인하였고, 이후 폴리우레탄폼 경화 단계에서 암모니아 가스의 생성을 증가시켰으며 B1보다 B3가 위험성이 더욱 높은 것을 확인하였다.

      • SCOPUSKCI등재

        아크릴 단량체 종류 변화가 수분산 Polyurethane Dispersion의 물성에 미치는 영향

        신용탁 ( Yong Tak Shin ),홍민기 ( Min Gi Hong ),김병석 ( Byung Suk Kim ),이원기 ( Won Ki Lee ),유병원 ( Byung Won Yoo ),이명구 ( Myung Goo Lee ),송기창 ( Ki Chang Song ) 한국화학공학회 2011 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.49 No.5

        NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), polycarbonate diol(PCD) and dimethylol propionic acid(DMPA). Subsequently, acrylic terminated polyurethanes were prepared by capping the NCO groups of polyurethane prepolymers with different types of acrylate monomers, such as 2-hydroxyethyl methacrylate(HEMA), 2-hydroxyethyl acrylate(HEA) and pentaerythritol triacrylate(PETA). The average particle sizes of the acrylic terminated polyurethane solutions were increased by capping acrylate monomers. Also, the prepared coating films showed better abrasion resistance and pencil hardness than those of pure waterborne polyurethanes. The coating film with PETA exhibited the best abrasion resistance and pencil hardness of coating films prepared with three acrylate monomers.

      • SCOPUSKCI등재

        Pentaerythritol Triacrylate와 실란커플링제의 첨가가 수분산 폴리우레탄의 물성에 미치는 영향

        신용탁 ( Yong Tak Shin ),홍민기 ( Min Gi Hong ),김병석 ( Byung Suk Kim ),이원기 ( Won Ki Lee ),유병원 ( Byung Won Yoo ),이명구 ( Myung Goo Lee ),송기창 ( Ki Chang Song ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.2

        Acrylic terminated polyurethane prepolymers were synthesized by capping the NCO groups of polyurethane prepolymers, prepared from isophorone diisocyanate (IPDI), polycarbonate diol (PCD) and dimethylol propionic acid (DMPA), with pentaerythritol triacrylate (PETA). Subsequently, silylated acrylic terminated prepolymers were prepared by capping the NCO groups of acrylic terminated polyurethane prepolymers with different types of silane coupling agents, glycidoxypropyl trimethoxysilane (GPTMS) or aminopropyl triethoxysilane (APS). The average particle size of pure waterborne polyurethane solution, measured by the dynamic light scattering method, was increased from 14.3 nm to 208.6 nm by adding PETA and APS. Also, the coating film of silylated acrylic terminated waterborne polyurethane showed better abrasion resistance and pencil hardness than that of pure waterborne polyurethane.

      • KCI등재

        냉동 컨테이너용 경질 폴리우레탄 폼 단열재 표준연구

        이준혁 ( Joon-hyuk Lee ),박용근 ( Yong-geun Park ),주아람 ( A-ram Joo ),정용안 ( Yong-an Jung ),이순홍 ( Soon-hong Lee ) 한국안전학회(구 한국산업안전학회) 2017 한국안전학회지 Vol.32 No.1

        According to an increase in demand for polyurethane soft foam for thermally insulated containers, the purpose of this study is based on redefining existing rigid polyurethane foam insulation KS standard which has been limited to building material-based authentication techniques. Since there are arising concerns of consumer rights and safety due to humidifier fungicides and urethane track incidents, there are elements to be further researched on rigid polyurethane foam insulation for refregerated containers. Thus, we reviewed the prior standards for rigid polyurethane foam insulation and verified the validity of certification testing method for the new standard with self-foamed polyurethane.

      • SCOPUSKCI등재

        Enhanced Production of Shikonin by Using Polyurethane-entrapped Lithospermum erythrorhizon Cells

        Taek, Seo-Weon,Liu, Jang-Ryol,Park, Young-Hoon 한국미생물 · 생명공학회 1989 한국미생물·생명공학회지 Vol.17 No.4

        L. erythrorhizon 세포를 polyurethane foam과 함께 증식시킬 경우 shikonin 유도체가 polyurethane에 효과적으로 흡착됨과 동시에 polyurethane을 사용하지 않은 경우와 비교하여 shikonin 생산량이 현저히 증가하였다. 이 같은 증가는 세포를 polyurethane pore에 고정하여 증식시킴으로써 원활한 세포간 접촉을 유지하고 세포 내에 shikonin 농도를 저하시켜shikonin 생성에 좋은 조건을 제공함에 기인한 것으로 생각되었다. 공정의 생산성을 높이기 위하여 여러가지 배양시스템이 검토되었는데, indole-3-acetic acid(1.75mg/ι)와 kinetin(0.1mg/ι)을 함유하는 Schenk-Hildebrandt 배지 (SHIK 배지) 시스템이 가장 효과적이었다. p-Chlorophenoxyacetic acid (2.0 mg/ι)와 kinetin (0.1 mg/ι)를 함유하는 Schenk-Hildebrandt 배지 (SHND 배지) 시스템에 비교하여 SHIK 배지 시스템에서 Shikonin 생성량은 약 4.5배 증가하였다. Polyurethane을 세포를 고정화하는 지지체로 사용할 경우에는 현재 행하여지고 있는 2단계 배양보다 1단계 배양이 더욱 효과적이며 경제적으로도 매우 유리할 것으로 판단되었다. Production of shikonin derivatives by Lithospermum erythrorhizon cells by using polyurethane foam was invesliigated. Shikonin derivatives were effectively adsorbed mostly by phase distribution to polyurethane matrices and their production increased significantly compared to the suspension culture. The enhanced production of shikonin was probably due to more facilitated cell to cell con-tact and lowered intracellular shikonin concentration, both of which are known to be favorable for plant secondary metabolite production. In order to improve the process productivity, tell culture was conducted under various culture conditions: Of them, Schenk and Hildebrandt medium containing indole-3-acetic acid (1.75mg/ι) and kinetin (0.1mg/ι) was considered most appropriate for shikonin production. Production of shikonin increased about 4.5 times in the Schenk and Hildebrandt medium containing indole-3-acetic acid (1.15mg/ι) and kinetin (0.1mg/ι) when compared to the same medium containing p-chlorophenoxyacetic acid (2.0mg/ι) and kinetin (0.1mg/ι). When poly-urethane was used as the support material, a single-stage system was more preferred to the conventional two-stage culture system in terms of shikonin productivity.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼