• 제목/요약/키워드: additive effects

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Influence of microbial additive on microbial populations, ensiling characteristics, and spoilage loss of delayed sealing silage of Napier grass

  • Cai, Yimin;Du, Zhumei;Yamasaki, Seishi;Nguluve, Damiao;Tinga, Benedito;Macome, Felicidade;Oya, Tetsuji
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권7호
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    • pp.1103-1112
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    • 2020
  • Objective: To measure whether a microbial additive could effectively improve the fermentation quality of delayed-sealing (DS) silage, we studied the effects of inoculants of lactic acid bacteria (LAB) and cellulase enzyme on microbial populations, ensiling characteristics, and spoilage loss of DS silage of Napier grass in Africa. Methods: Quick-sealing (QS) and DS silages were prepared with and without LAB (Lactobacillus plantarum) inoculant, cellulase enzymes, and their combination. The QS material was directly chopped and packed into a bunker silo. The DS material was packed into the silo with a delay of 24 h from harvest. Results: In the QS silage, LAB was dominant in the microbial population and produced large amounts of lactic acid. When the silage was treated with LAB and cellulase, the fermentation quality was improved. In the DS silage, aerobic bacteria and yeasts were the dominant microbes and all the silages were of poor quality. The yeast and mold counts in the DS silage were high, and they increased rapidly during aerobic exposure. As a result, the DS silages spoiled faster than the QS silages upon aerobic exposure. Conclusion: DS results in poor silage fermentation and aerobic deterioration. The microbial additive improved QS silage fermentation but was not effective for DS silage.

선박연료유의 정제처리 및 첨가제 혼합에 따른 물리.화학적 특성 변화에 관한 연구 (A Study on the Variation of Physical & chemical Properties with Refining treatment and Additive mixture for Marine Fuel Oil)

  • 한원희;남정길;이돈출;박정대;강대선
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2006년도 추계학술발표회
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    • pp.291-297
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    • 2006
  • 최근 국제 유가의 상승으로 인한 선박 운용비를 절감하기 위하여 중소형 선박에서도 저질연료유의 사용이 검토되고 있는 추세이다. 이 연구에서는 현재 중소형 선박에서 연료유로 사용중인 경유와 중유 MF380 을 혼합하여 소형선박에 사용이 가능하도록 제조한 혼합연료유인 MF30 연료유에 대하여 그 물리 화학적 특성을 분석하고 정제처리 및 연료유첨가제 효과에 대해 알아보았다. 연구 결과 두가지 전처리 방식인 원심식청정기와 가열 및 균질 방식 (M.C.H) 의 효과는 다소 미약하였지만, 유동점과 인화점은 다소 낮아졌다. 연료유첨가제로 인한 개질 효과는 뚜렷이 나타나지 않았다.

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광 산란 기술을 이용한 연료 첨가제의 그을음 억제 효과 분석 (Analysis of Effect of Fuel Additive on Soot Suppression Using Laser Scattering Technique)

  • 서형석;김기범
    • 한국산학기술학회논문지
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    • 제17권7호
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    • pp.204-210
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    • 2016
  • 본 논문에서는 이소 옥탄을 연료로 사용하는 층류 확산 화염에서 불완전 연소의 결과로 발생하는 그을음 입자의 성장 및 산화과정을 조사하였다. 또한, 철 연료첨가제의 그을음 발생 억제 효과를 평가하였다. 광 계측 기술을 이용하여 화염 안 그을음 입자의 탄성 산란 광을 화염의 높이에 따라 계측하고, 미광 보정 과정을 통하여 그을음 입자의 미분 산란 계수를 구하였다. 이 미분 산란 계수를 비교하여, 화염에서 그을음 입자의 성장 및 산화과정을 조사하였는데, 산화과정을 통하여 화염 내의 그을음 양이 감소하는 것을 관찰하였다. 철 연료 첨가제를 첨가한 화염에 대해서 동일한 연구 방법으로 구한 미분 산란 계수가 연료 첨가제가 첨가되지 않은 화염보다 더 작은 값을 보였다. 또한, 화염의 높이에 따라 반경방향으로 투과율을 측정하였는데, 연료 첨가제를 첨가한 연료의 화염은 투과율이 산화영역에서 약 5% 증가하는 것을 관찰하였고, 이는 미분 산란 계수와 동일한 경향을 보였다. 이것은 연료첨가제의 성분이 촉매 역할을 하여 그을음이 산화를 촉진해 화염 안의 그을음 양이 감소한 것으로 사료된다.

액상첨가제에 의한 칼라로도 블록 무기 안료층의 특성 향상 (Enhancement in the physical properties of inorganic pigment layer in the color block by incorporation of n liquid additive)

  • 이동명;박동욱;이준희;김상민;김대영;김정조;김진곤;조현
    • 한국결정성장학회지
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    • 제16권5호
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    • pp.222-226
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    • 2006
  • Carboxylated styrene-butadiene계 액상 첨가제가 칼라 보도 블록 무기 안료층의 미세구조, 기계적 특성 및 탈색 저항성에 미치는 영향에 대하여 조사하였다. 액상 첨가제를 첨가함에 따라 겉보기 기공률과 흡수율이 감소한 더 치밀한 미세구조와 균일한 안료 분포를 나타내는 무기 안료층을 얻을 수 있었다. 또한 기계적 강도 및 탈색저항성이 현저히 향상됨을 확인하였다.

Effects of Additives on the Properties of $YBa_2Cu_3O_x$

  • Soh, Dea-Wha;Cho, Yong-Joon;Fan, Zhanguo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.341-344
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    • 2004
  • The superconducting properties of $YBa_2Cu_3O_x$ with different content impurities of PbO and $BaPbO_3$ were studied. When the PbO was used as an additive in $YBa_2Cu_3O_x$, although the melting point could be reduced, the superconductivity became poor. From the XRD pattern of the sintered mixture of $YBa_2Cu_3O_x$ and PbO it was known that there is a reaction between $YBa_2Cu_3O_x$ and PbO, and the product is $BaPbO_3$. In the process of the reaction the superconducting phase of $YBa_2Cu_3O_x$ was decreased and $BaPbO_3$ would be the main phase in the sample. Therefore, $BaPbO_3$ was chosen as the impurity additive for the comparative study. The single phase of $BaPbO_3$ was synthesized by the simple way from both mixtures of $BaCO_3$ and PbO, $BaCO_3$ and $PbO_2$. Different contents of $BaPbO_3$ (10%, 20%, 30%) were added in the $YBa_2Cu_3O_x$. By the Phase analysis in the XRD patterns it was proved that there was no reaction between $YBa_2Cu_3O_x$ and $BaPbO_3$. When $BaPbO_3$ was used as impurity in $YBa_2Cu_3O_x$ the superconductivity was much better than PbO as an impurity additive in $YBa_2Cu_3O_x$.

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식품의 안전성 및 식품첨가물에 대한 소비자 인식에 관한 연구 (A Study on the Consumer Recognition of Food Safety and Food Additives)

  • 한왕근;이귀주
    • 한국식품조리과학회지
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    • 제7권4호
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    • pp.23-34
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    • 1991
  • This study was to investigate consumer recognition of food safety and food additives. The results of this study are as follows: 1. When shopping for food, the food safety was rated as foremost concern for the respondents and the details checked most often were manufacture date, packing condition and axpiration date, respectively. When asked their opinion about harmful factors in relation to food safety, the most important consideration was food additives. The highest rating for credibility regarding the sources of information on food was given to scientists in university and institute, lowest one was given to food manufacturer. 2. Government regulation on the use of food additives was known to exist, but control of the uses of food additive was considered inadequate by 60% of the respondents. These results showed significant differences for age (p<0.05), for education level (p<.01) and for income (p<.05) respectively. 3. 47.9% of the respondents indicated that they were willing to purchase the additive free foods, although it was expensive. More than 70% made an effort to eat food with less food additive and were concerned about possible effects of food additives on health, showing significant differences for age (p<0.05), for education level (p<0.05) and for income (p<0.05). 4. Labeling for food additive found on food package was shown to be unsatisfactory, showing significant difference only for income (p<0.05) and more information about food was needed by over 91.3% of the respondents, showing significant difference for education level (p<0.05). 5. Although approximately 80% of the respondents were concerned about artificial preservative, artificial flavor, artificial color and artificial sweetener, the concern about artificial preservative was the highest. Primary causes that respondents felt fear toward food additives were the unknown harms and cancer, and primary sources that respondents got information on food were televison and radio, respectively. From these results, it was shown that consumer considered food safety important and they felt a great deal of concern about food additives.

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선박연료유의 정제처리 및 첨가제 혼합에 따른 물리.화학적 특성 변화에 관한 연구 (A Study on the Variation of Physical & Chemical Properties with Refining Treatment and Additive Mixture for Marine Fuel Oil)

  • 한원희;남정길;이돈출
    • 해양환경안전학회지
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    • 제13권1호
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    • pp.39-45
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    • 2007
  • 최근 국제 유가의 상승으로 인한 선박 운용비를 절감하기 위하여 중소형 선박에서도 저질연료유의 사용이 검토되고 있는 추세이다. 이 연구에서는 현재 중소형 선박에서 연료유로 사용중인 경유와 중유MF380을 혼합하여 소형선박에 사용이 가능하도록 제조한 혼합연료유인 MF30 연료유에 대하여 그 물리 화학적 특성을 분석하고 정제처리 및 연료유첨가제 효과에 대해 알아보았다. 연구결과 두 가지 전처리 방식인 원심식청정기와 가열 및 균질 방식(M.C.H)의 효과는 다소 미약하였지만, 유동점과 인화점은 다소 낮아졌다. 연료유첨가제로 인한 개질 효과는 뚜렷이 나타나지 않았다.

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혼합물 실험계획법을 이용한 유색 EPDM의 첨가제 배합비에 따른 기계적 특성 분석 (Analysis of Mechanical Properties of Colored EPDM Based on Additive Mixing Ratio Using Mixture Design of Experimental Method)

  • 박윤아;전의식;김영신;이현승
    • 한국기계가공학회지
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    • 제21권8호
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    • pp.79-86
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    • 2022
  • With the recent increase in the demand for electric vehicles, it is necessary to identify the high current safety of automobile parts. Among the automobile parts, the EPDM parts required colored parts from the existing black; therefore, it was necessary to change the basic filler from carbon black to silica. The rubber used in automobile parts is flexible and exhibits basic characteristics of high strength and elongation. However, as the filler is changed to silica, its physical properties, such as tensile strength and elongation, are lower than those of the existing carbon black base. Therefore, it is necessary to evaluate the mechanical properties with the addition of the EPDM compound using silica as a base without degrading the physical properties of EPDM. In this study, an experiment based on the additive content was performed using the mixture experimental planning method to analyze the mechanical properties according to the additive type and mixing ratio of silica-based EPDM. The mixing ratio of the four additives was set using a simplex lattice design, and the tensile strength, elongation, modulus 300%, and permanent compression reduction rate were analyzed for mechanical characteristics, and rheometer experiments were performed for vulcanization characteristics. Through statistical analysis of the measured data, the main effects and interactions of the EPDM-blended rubber additives were analyzed. These results can be used to derive a mixing ratio of additives that satisfies the required characteristics of the EPDM compound.