• 제목/요약/키워드: bleaching

검색결과 614건 처리시간 0.034초

O, Eo 및 C/D단계를 이용한 신갈나무 크라프트펄프표백 (Bleaching of Oak Kraft Pulp by O, Eo and C/D Stage)

  • 김동호;백기현
    • 펄프종이기술
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    • 제29권3호
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    • pp.43-50
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    • 1997
  • The purpose of this study was to decrease pollutants of effluents from KP bleaching. Multistage bleaching that combined with O, Eo, and C/D stage was conducted, after optimum bleaching conditions of O, Eo, and C/D stage were determined. Moreover the properties for bleached pulps and pollution level of bleaching effluent were measured by each standard method. Due to increase on the brightness and delignification of pulps by O, Eo, and C/D stage bleaching. It was possible that bleaching sequences were reduced from five stage to four stage. In addition to, OC/DEoD and OC/DEopD bleaching sequences had higher brightness than CEDED bleaching sequence. The pulps bleached by O and Eo stage had higher in tensile index than conventional bleaching sequences with the similar results in burst and tear index. While each bleaching sequences had little differences, bleaching sequences with Eo stage had higher in physical properties than with Eop stage. The pollution level measured by Chemical Oxygen Demand(COD), Biochemical Oxygen Demand(BOD) and Color of bleaching effluents were much lower in combined bleaching sequences of O, Eo and C/D stage than that of CEDED sequence. Particularly, a pollution index of bleaching effluents generated by C/DEoDEB and OC/DEopDED bleaching sequences were lower than that from the other bleaching sequences.

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육계의 사료원으로 식용유 정제 폐백토(Spent Bleaching Clay)의 평가에 관한 연구 (Studies on Evaluation of Spent Bleaching Clay as a Feed Ingredient in Broiler Chicks)

  • 전해열;손장호
    • 한국가금학회지
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    • 제34권2호
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    • pp.99-104
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    • 2007
  • 본 연구는 식용유 정제 폐백토(spent bleaching clay)를 육계 사료 원료로 가치를 평가하기 위해서 실시하였다. 식용유 정제 폐백토(spent bleaching clay)는 대두유의 정제 과정에서 생산되어지며, 생 식용유 정제 폐백토(spent bleaching clay)속에는 조지방(26.0%)과 조회분(68.3%)은 풍부하나, 수분(5.2%)과 조단백질(0.5%)의 함량은 낮게 평가되었다. 식용유 정제 폐백토(spent bleaching clay)와 대두유의 산가는 각각 9.72 및 0.001로 유의한 차이가 인정되었다(P<0.05). 뿐만아니라 식용유 정제 폐백토(spent bleaching clay)의 과산화물가는 대두유보다 유의하게 높아서(P<0.05) 식용유 정제 폐백토(spent bleaching clay)의 빠른 산패 가능성을 시사한 결과이다. 그러나 식용유 정제 폐백토(spent bleaching clay)의 산패는 인공적인 방법으로 막을 수 있을 것이다. 한편 식용유 정제 폐백토(spent bleaching clay)의 육계 사육에서의 $2.0{\sim}4.0%$의 첨가는 사료 섭취량, 증체량 및 사료 효율을 개선시켰다. 결론적으로 육계 사료에 $2.0{\sim}4.0%$의 식용유 정제 폐백토(spent bleaching clay)의 이용이 가능할 것으로 사료된다.

Surface Damage and Bleaching Effect according to the Application Type of Home Tooth Bleaching Applicants

  • Tak, Na-Yeoun;Lim, Do-Seon;Lim, Hee-Jung;Jung, Im-Hee
    • 치위생과학회지
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    • 제20권4호
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    • pp.252-260
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    • 2020
  • Background: In this study, the bleaching effect and surface damage of two types of over-the-counter home tooth bleaching agents were explored using an in vitro study of bleaching agents applied to bovine teeth specimens for 14 days. Methods: Domestic over-the-counter home tooth bleaching agents of gel and patch form that shared common active ingredients and manufacturers were selected and tested. The experiment specimens were made using composite resin with bovine tooth samples and then measured the initial microhardness. Specimens were then divided into a Gel group and a Patch group and underwent bleaching treatment once a day for two weeks for 30 to 60 minutes (recommended) or 7 hours. All specimens were coffee-stained prior to bleaching. The bleaching effect was measured using a spectrophotometer and surface damage was measured using a microhardness meter. Results: The difference in color following the bleaching procedure was positive in both the Gel and Patch group, although there were no statistically significant differences in bleaching effect between groups. There was no significant difference in bleaching effect based on duration. The microhardness test revealed that both the Gel group and the Patch group had surface damage after bleaching. The greatest surface damage was found in the Patch group that had undergone a 7-hour bleaching treatment, although the differences were not statistically significant. Conclusion: The bleaching effect of the home tooth bleaching agent was visible to the naked eye. However, longer applications than recommended did not result in greater bleaching, unlike consumers' expectations, and instead increased the chance of enamel damage. As such, there is a need for consumers to be alert and adhere to recommendations provided by each company.

오존을 이용한 신갈나무 크라프트펄프의 무염소표백 (Non-chlorine Bleaching of Oak Kraft Pulp by Ozone)

  • 김동호;백기현
    • 펄프종이기술
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    • 제29권2호
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    • pp.36-45
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    • 1997
  • Newly bleaching sequence using oxygen, ozone and hydrogen peroxide has introduced to avoid pollution hazards from chlorinated organic compounds, because chlorine dioxide substitution bleaching was produced a little chlorinated organic substance. Oxygen-type chemicals replaced for chlorine has attracted much research attention. Bleachability of ozone was improved at low temperature and high pulp consistency. In third bleaching followed OZ bleaching, addition of O2 and NaBH4 in alkali extraction was effective than only alkali extraction. Bleachability of pulps in ozone bleaching(Z) was improved at higher consistency and lower temperature The addition O2 and NaBH4 in alkali extraction after OZ bleaching sequence improved brightness, when compared to those obtained by only alkaline extraction. Pulps bleached by ECF bleaching sequences such as OZEoD and OZEopD was obtained by 90% ISO brightness. The brightness of pulp bleached by TCF sequences with the ozone dosage of 1.6% was approached to target brightness (88~90%ISO). Pulps bleached Z stage combined bleaching sequence was reduced the viscosity to a little greater extent. However, physical properties of pulps was not great different compared to those bleached by conventional bleaching sequences. A pollution index of bleaching effluente by ozone combined bleaching sequences was lower than by conventional bleaching sequence, but somewhat higher than multistage bleaching sequences combined C/D stage.

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대나무화학펄프의 다단표백에 관한 연구 (Studies on the Multistage Bleaching of Bamboo Chemical Pulps)

  • 강진하;박성종
    • 펄프종이기술
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    • 제33권4호
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    • pp.49-54
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    • 2001
  • This study was carried out to acquire basic data for the bleaching of bamboo chemical pulp. Bamboo chemical pulps (alkaline sulfite (AS)-anthraquinone (AQ) pulp, Kraft pulp) were bleached with two kinds of multistage bleaching methods (CEDED, PDED) using the various kinds of bleaching agents. And, physical properties of bleached pulps were investigated. The conclusions obtained from the results were as follows; The yield of AS-AQ pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The brightness of kraft pulp bleached with five-stages bleaching method using the chlorine and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The physical properties of kraft pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps.

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치아미백에 관한 부산시민의 인식 및 지식도 조사 연구 (A research on the questionnaires about Busan citizen's understanding of the Tooth Bleaching)

  • 이혜진;전은숙
    • 한국치위생학회지
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    • 제6권1호
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    • pp.79-91
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    • 2006
  • Through the investigation and analysis for awareness about Tooth Bleaching treatment for general adults, to rethink the real ideas of Tooth Bleaching which adults has already had and to find the method for generalized Tooth Bleaching, this study made a survey about General Awareness and Common sense for Tooth Bleaching and Oral Health Knowledge and Generalization Methods for 570adult citizen in Busan from 1th August to 10th September. The obtained results were as follows 1. Tooth Shade self contentment was found low, self-discontent respondents were 73.5% and self-content respondents were 26.5%. 2. Tooth Bleaching recognition was found high, as for the recognition period, between 2 and 5 years is 65.5% and as for the recognition route, 33.9% were through broadcast medium. 3. General knowledge for Tooth Bleaching was found low as 2.34(1.12) of 5 score and it is similar to ages and occupations(pE0.001, pE0.05). 4. Tooth Bleaching treatment method appears Home Bleaching and In-Office bleaching was 73.5% and 26.5% respectively. The other side medical institution chosen for Tooth Bleaching treatment appears dental hospital or dental clinic and Home bleaching was 75.6% and 12.1% respectively. 5. To generalize the Tooth Bleaching Care, recommendations of oral health care team and oral health education and development of information data also need to be performed.

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치위생과와 비치위생과 학생의 치아미백에 대한 인식도 및 실태조사 (A servey on the actual conditions & recognition of tooth bleaching in female college students)

  • 신민우;지민경;한명숙
    • 한국치위생학회지
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    • 제8권4호
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    • pp.43-53
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    • 2008
  • Some female college students have to recognize and understand the actual conditions of the tooth bleaching, and effective consultation and training to provide basic data for the purpose of investigation. this study made a survey about recognize and understand the actual conditions of the tooth bleaching and oral health knowledge and generalization methods for 649 female college student in Daejeon and Jeonbuk areas during the period between March. 15 and April. 10,2008. The results were as follows: 1. Tooth Status was found low, self-discontent respondents Status 44.2% and average 31.1%, self-contentment were 14.8%. Tooth color was average respondents were 69.8%, yellow 29.0%, White 1.7% (p=0.001, p=0.030). 2. Tooth bleaching experience has not experienced the most the military was 86.4%, to the desired Tooth bleaching for the external beauty 44.2%, confidence of smile time 37.5%. self-discontent 10.7%(p=0.000, p=0.000). 3. Tooth health status satisfaction was dental hygiene students higher than non dental hygiene, and scaling knowledge of the Tooth bleaching effect was non dental hygiene higher than non dental hygiene(p=0.039, p=0.000). 4. General knowledge for Tooth bleaching was found high 96.1%, as for the recognition route, 55.6% were through broadcast medium(p=0.025, p=0.000). 5. Medical institution chosen for Tooth bleaching treatment method appears the most preferred by 79.9% to the dental hospital dental clinic. 6. Important to consider that the choice of Tooth bleaching was Tooth bleaching duration of 37.1% cost 33%, And when Tooth bleaching hoped to be long-lasting. In this research the high recognized of Tooth bleaching treatment, but very low Tooth bleaching experience female college students for the Tooth bleaching had the wrong information. Therefore, Tooth bleaching treatment and counseling that can be used to development and education were required to provide the correct information.

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Thiourea 첨가에 의한 MOW의 산화-환원 연속 표백 (Sequential Oxidative and Reductive Bleaching of MOW by the Addition of Thiourea)

  • 김승호;안병준;백기현
    • 펄프종이기술
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    • 제34권3호
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    • pp.38-45
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    • 2002
  • The effect of sequential oxidative-reductive bleaching on brightening of the MOWs is investigated. The improvement in brightnesses of MOWs is more effective in conventional PFAS bleaching than in P/T bleaching. There is no difference in the mechanical properties or the bleached pulps between PFAS and P/T sequences. Considering the brightness gains and bleaching chemicals cost, for the MOW A(Initial brightness: 68.3% ISO) containing 5% ONP and 20% colored paper, the P/T bleaching is more economical than the PFAS bleaching. However for MOW B(initial brightness: 59.1% ISO) containing 15% ONP and 35% colored paper, there is no difference in the bleaching efficiency between PFAS and P/T bleaching.

인삼 엽소병에서 색소의 광산화작용에 관한 연구 1. Chlorophyll bleaching의 현상학적 연구 (Investigation on the Photooxidation of Pigment in Leaf-Burning Disease of Panax ginseng 1. Phenomenological observation and analysis on the chlorophyll bleaching phenomenon)

  • 양덕조;유희수;윤재준
    • Journal of Ginseng Research
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    • 제11권2호
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    • pp.91-100
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    • 1987
  • 인삼(Panax ginseng C.A. Meyer) 엽소병에 대한 고사원인을 현상학적 측면에서 관찰, 분석한 결과 chlorohphyll의 bleaching현상은 적색광(660~700nm)에서 일어났으며, 청색광(400~500nm)에서는 광산화에 의한 bleaching현상이 일어나지 않았다. 엽소병에 의한 고사원인으로 대두되었던 환경요인 "온도"는 chlorohphyll의 bleaching현상에 전혀 영향을 미치지 않았다. 따라서 단순연소(simple burning)설은 본 실험을 통해 배재되었으며, 낮은 pH는 chlorohphyll의 bleaching속도를 가속화시켜 주었다. 엽소병에서 chlorohphyll의 bleaching현상을 유발시키는 1차적요인은 인삼잎의 독특한 구조적 차이에 의한 것이었다.

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치아미백에 대한 지식과 만족도 현황 (Knowledge and Satisfaction Status of Tooth Bleaching)

  • 정유란;이주열
    • 한국콘텐츠학회논문지
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    • 제18권10호
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    • pp.403-414
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    • 2018
  • 본 연구는 치아미백에 대한 지식과 만족도를 알아보고자 하는 것이다. 2017년 6월1일부터 2주 동안 울산광역시에 위치한 치과의원에 방문한 환자 328명을 대상으로 자기기입식 설문 조사를 실시하였다. 연구결과 치아미백 지식수준에 따른 치아미백만족도는 통계적으로 유의하지 않았으며, 치아미백지식수준이 상(8-10)인 경우 만족도가 3.86으로 가장 높았으며 하(0-3)인 경우 만족도가 3.00으로 가장 낮았다. 일반적인 특성에 따른 치아미백 만족도는 성별과 연령에서 통계적으로 유의하게(p<0.05) 나타났으며, 여자의 만족도가 3.74로 남자의 만족도 3.11 보다 높았다. 미백경험방법과 미백동기에 따른 만족도는 통계적으로 유의하였으며(p<0.05), 전문가 미백(4.41)이 OCT미백(2.64)보다 높았다. 또한 병원의 권유로 미백을 한 경우 4.13점으로 매체광고를 통해 미백을 경험한 경우(3.00) 보다 높았다. 따라서 치아미백의 만족도는 대상자의 일반적인 특성 뿐만 아니라 치아미백에 관한 지식수준, 치아미백 방법과 치아미백 동기에 영향을 받았다. 이러한 요인을 활용하여 치아미백의 경험과 만족도를 향상시키기 위한 치료계획을 세우는데 유용하게 사용될 수 있을 것이다.