• 제목/요약/키워드: rice husk flour

검색결과 14건 처리시간 0.018초

Comparison of Formaldehyde Emission Rate and Formaldehyde Content from Rice Husk Flour Filled Particleboard Bonded with Urea-Formaldehyde Resin

  • Lee, Young-Kyu;Kim, Sumin;Kim, Hyun-Joong;Lee, Hwa Hyoung;Yoon, Dong-Won
    • Journal of the Korean Wood Science and Technology
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    • 제34권5호
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    • pp.42-51
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    • 2006
  • The this study, the effect of rice husk flour (RHF) as scavenger on formaldehyde emission rate and formaldehyde content from urea-formaldehyde (UF) resin bonded RHF content wood particleboards (PB). Two type of particle size ($30{\mu}m$ and $300{\mu}m$) of RHF was premixed with the UF resin at 5% and 15% by weight. The performance of UF resins is greatly influenced by the curing characteristics in their curing processing. The curing behavior was monitored activation energy ($E_a$) by DSC and pH variation according to RHF contents. PB with dimensions of $27cm{\times}27cm{\times}0.7cm$ was prepared at a specific gravity of 0.75 using $E_1$ and $E_2$ class UF resins. Formaldehyde emission and formaldehyde content from RHF filled PB bonded with UF resin was measured by 24 h desiccator and perforator method, respectively. RHF causes an increased pH of UF resin. $E_a$ of the modified UF resin decreased independently of RHF particle size. As the pH and the $E_a$ variation of the UF resin containing RHF increased, the amount of formaldehyde content decreased. The formaldehyde emission and formaldehyde content levels of the PB bonded with 15 wt% of $30{\mu}m$ RHF and $E_2$ type UF resin were low and satisfied grade $E_1$, as measured by 24 h desiccator and perforator method. The result of a comparison between 24 h desiccator and perforator test using PB showed that the linear regression analyses show a good correlation between the results for the 24 h desiccator and the perforator tests. The linear regression of a correlation between the desiccator and the perforator was Y=4.842X-0.064 ($R^2=0.989$). RHF was effective at reducing formaldehyde emission and formaldehyde content in urea-formaldehyde adhesives when used as scavenger.

표면처리에 의한 왕겨분말-폴리프로필렌 바이오복합재의 계면 접착력 향상 (Improvement of Interfacial Adhesion for Surface treated Rice Husk Flour-Filled Polypropylene Bio-Composites)

  • 이병호;김희수;최성우;김현중
    • Journal of the Korean Wood Science and Technology
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    • 제34권3호
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    • pp.38-45
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    • 2006
  • 본 연구의 목적은 왕겨분말을 NaOH와 acetic acid 처리를 통하여 왕겨분말-폴리프로필렌(PP) 바이오복합재의 계면 결합을 증가시키는 것이다. 처리하지 않은 왕겨분말, NaOH와 acetic acid 처리된 왕겨분말을 충전제로 사용하여 바이오복합재를 제조한 후 왕겨분말의 처리에 대한 효과를 조사하였다. NaOH와 acetic acid 처리된 왕겨분말이 충전된 바이오복합재의 인장강도가 처리하지 않은 왕겨분말이 충전된 바이오복합재보다 증가하였다. NaOH와 acetic acid로 처리 전후의 왕겨분말 표면은 scanning electron microscopy (SEM)의 사진으로 명확하게 관찰할 수 있었다. SEM을 이용하여 측정한 결과 왕겨분말 표면의 이물질이 제거된 것을 발견 할 수 있었다. NaOH와 acetic acid 처리된 왕겨분말의 화학적 구조는 fourier transform infrared (FTIR)을 이용하여 분석하였다. 처리하지 않은 왕겨분말, NaOH와 acetic acid로 처리된 왕겨분말의 결정화구조 및 결정화도는 wide-angle X-ray scattering (WAXS)을 이용하여 분석하였다.

Revealing the Spatial Distribution of Inorganic Elements in Rice Grains

  • Jeon, Ji Suk;Choi, Sung Hwa;Lee, Ji Yeon;Kim, Ji A;Yang, Young Mi;Song, Eun Ji;Kim, Jae Sung;Yang, Jung Seok;Kim, Kyong Su;Yoo, Jong Hyun;Kim, Hai Dong;Park, Kyung Su
    • Bulletin of the Korean Chemical Society
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    • 제35권11호
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    • pp.3289-3293
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    • 2014
  • Femtosecond laser ablation (fs LA) was used in this study to identify pollution by heavy metals and the distribution of elemental nutrients at different rice milling ratios. Polished rice (degrees of milling of 3, 5, 7, 9, and 11) was collected from major Korean supermarkets and one sample thereof was selected. An internal quality control experiment was conducted using a rice flour certified reference material from the Korea Research Institute of Standards and Science (KRISS CRM) for the evaluation of the efficacy. To assess the effectiveness of the analysis method, the reliability was validated using a food analysis performance assessment scheme (FAPAS), with chili powder serving as an external quality control. The results of the analysis of the inorganic elements Ti, Ca, Al, Fe and Mn in white and brown rice with degrees of milling of 3, 5, 7, 9 and 11 using ICP-MS, ICP-OES and AAS revealed contents of 0.40, 49.2, 2.43, 5.36 and 10.3 mg/kg in white rice and 0.59, 78.0, 7.52, 11.0 and 18.5 mg/kg in brown rice, respectively. Among the elements, there were remarkable differences in the measured contents. By comparing the contents of the elements at different degrees of milling, Ti, Co, As, Ca, Al, Cu, Fe, and Mn were determined to be distributed on the surface of the rice grains, whereas the contents of Cd and Pb increased toward the center of the rice grains, and Si was evenly distributed. After the quantitative analysis of rice samples polished to different degrees of milling, Ca and Al, which were contained in large amounts, and Si were analyzed with specificity by fs LA. The results show that Ca and Al were distributed in the rice husk (protective covering of rice) and Si was distributed in all parts of the rice.

실규모 심부화재 소화특성에 관한 연구 (A Study of Fire Extinguishment Characteristic for the Real Scale Deap-Seated Fire)

  • 김남균;이동호
    • 한국화재소방학회논문지
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    • 제29권2호
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    • pp.13-19
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    • 2015
  • 본 연구는 침윤소화약제의 소화성능평가를 위해 실규모 소화실험을 수행하였다. 실험은 '수동식소화기의 형식승인 및 검정기술기준'에 명시되어 있는 A급 소화실험 방법에 따라 진행하였으며, 목재 외에도 목분과 왕겨를 대상으로 실험을 진행하였다. 소화용수는 물과 국내에서 사용되고 있는 3종의 침윤소화약제를 사용하여 성능평가 실험을 진행함으로써 물과 침윤소화약제의 명확한 변별력을 확인하고자 하였다. 실험 결과 물의 경우에서 내부 온도의 유지시간이 길게 유지되고 침윤소화약제의 경우 빠른 온도 하강을 나타냄을 확인하였으며, 시간에 따른 온도분포를 통해 소화능력의 변별력을 확인하였다. 본 실험 결과를 바탕으로 추후 최적화 침윤소화약제 성능평가 방법을 제시하는데 기초자료로 활용할 수 있을 것으로 판단된다.