• 제목/요약/키워드: wet grinding

검색결과 74건 처리시간 0.029초

수종(數種) 표면처리제(表面處理劑)에 의(依)한 상아질(象牙質) 표면(表面)의 형태(形態) 변화(變化)에 관(關)한 연구(硏究) (MORPHOLOGICAL CHANGES OF DENTIN SURFACE TREATED WITH VARIOUS DENTIN SURFACE CONDITIONERS)

  • 조진호;최호영;민병순;박상진
    • Restorative Dentistry and Endodontics
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    • 제13권2호
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    • pp.323-334
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    • 1988
  • The purpose of this study was to observe the effect of dentin surface conditioners on the dentin surfaces. Freshly extracted human molars were used in this study. They were stored at $4^{\circ}C$ saline solution before experiment. The crown portions of the teeth were cut in various directions by means of wet diamond point to expose dentin which include transverse, vertical oblique, horizontal and oblique cut to the long axis (Fig. 1). Each tooth was then mounted with self curing acrylic resin in brass ring to expose the flattened dentin surfaces. Final finish was accomplished by grinding the dentin specimens with wet No. 180 and No. 600 grit silicon carbide abrasive paper until a 6.0mm in diameter on a dentin surface was exposed without pulp exposure. The specimens were divided into 9 groups according to the modes of dentin treatment procedure. The following surface treatments were applied on these preparation surfaces; Group 1: unetched (control group) after finish with No. 600 silicon carbide abrasive paper. Group 2: etched with 30% phosphoric acid for 60s Group 3: etched with 10-3 solution for 60s Group 4: Cleaned with 5% NaOCl for 30s Group 5: applied Dentin Adhesit Group 6: cleaned with 5% NaOCl followed by applying the Dentin Adhesit$^{(R)}$ Group 7: applied Photo Bond on the unetched dentin followed by applying the Photo Clearfil Bright Group 8: Etched with 30% phosphoric acid followed by applying Photo Bond and Photo Clearfil Bright Group 9: etched with 10-3 solution followed by applying Photo Bond and Photo Clearfil Bright All the specimens were stored in $37^{\circ}C$ under 50% relative humidity for 24 hours before observations. The specimens in 7, 8, and 9 group, omitting the group 1 to 6, were demineralized in 10% HCl for 10s in order to observe the resin tags. All the specimens in each group were then dried at room temperature. The dried specimens were ion coated with Eiko ion coater (Eiko-engineering Co.), and observed in Hitachi S-430 Scanning electron microscope (Hitachi, Co. Tokyo) at 15KV. The following results were obtained as follows; 1. The smear layers were still remained in group 1,2,4,5, and 6. 2. There is no effect of 5% NaOCl and 30% phosphoric acid on the changes of dentin morphology 3. The dentin treated with 10-3 solution, indicating the tubules opened when the smear layer and the dental plug dissolved. 4. In case of applying the bonding agents the resin tag was not formed at the deep area of dentinal tubules, but in case of applying the Dentin Adhesit$^{(R)}$ that was not.

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미더덕 껍질과 PVA를 혼합한 재료로부터 제조한 복합섬유의 제법과 성질(I) (Preparation and Properties of Regenerated Composite Fibers made from Styela Clava Tunics/PVA Blending(I))

  • 정영진;안병재;김홍성;최해욱;이언필;이재호;김한도;박수민;김성동
    • 한국염색가공학회지
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    • 제20권2호
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    • pp.1-8
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    • 2008
  • Regenerated composite fibers are prepared from solution(styela clava tunics /poly vinyl alchol) using N-methylmorpholine-N-oxide(NMMO)/water(87/13)(wt/wt) as a solvent by dry-wet spinning. The chemical cellulose (94%, ${\alpha}$-cellulose content) used for this study is extracted from styela clava tunics (SCT, Midduck), which are treated in chemical process and mechanical grinding. The structure and physical properties of regenerated composite fibers were investigated through IR-spetra, DSC, TGA and SEM. The optimal blend ratio of SCT/PVA for spinning solution was 70/30 and the total weight was 4% concentrations in NMMO/water solvent system. The fiber density, moisture contents and the degree of swelling were $1.5(g/cm^3)$ 10.2(%) and 365(%), respectively. The crystallinity index of composite fibers are decreased as the PVA contents increased. Thermal decomposition of composite fibers took place in two stages at around $250^{\circ}C$ and $550^{\circ}C$. The best thermal stability was obtained with 30% PVA contents.

콩비지의 식이섬유와 단백질 분리 (Separation of Tofu-residue (biji) into Dietary Fiber and Protein Fractions)

  • 이원종;최미라;쏘설스키
    • 한국식품과학회지
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    • 제24권1호
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    • pp.97-100
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    • 1992
  • 실험실에서 제조된 비지는 약 57%의 식이섬유와 20%의 단백질을 함유한 반면, 시판용 비지는 약 59%의 식이섬유와 17%의 단백질을 함유하였다. 비지와 두부의 총식이섬유중 수용성 식이섬유는 3%와 46%를 차지하였다. 비지를 2회 분홰후 사별하고 액체부분을 원심분리한 결과 체위의 비지 식이섬유함량은 58.7%에서 80.6%로 증가되었고 식이섬유회수율은 90.4%이었다. 원심 분리후의 고형물은 46.8%의 단백질을 함유하였고, 단백질의 회수율은 29.2%를 나타냈다. 체위의 비지 지질함량은 처리전보다 훨씬 낮았다.

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Rice pasta containing cultivar 'Saemimyeon' with high amylose contents and methods thereof

  • Cho, Jun Hyeon;Lee, Ji Yoon;Lee, Jong Hee;Son, Young Bo;Shin, Dong Jin;Han, Sang Ik;Song, You Chun;Park, Dong Soo;Oh, Myung Kyu
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.253-253
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    • 2017
  • Recently, strong interest in the well-being and healthy food trends lead a spreading of rice processing products such as rice noodles, rice breads, and rice cakes. However, most of rice varieties developed in Korea showed very limited processing properties in processing of noodles compare to that of wheat flour. Moreover, low competitiveness as a raw processing materials due to high price give poor evaluations for rice noodles processing. To cope those barriers, 'Saemimyeon' a Tongil type high yielding variety with a high amylose contents was developed in RDA. 'Saemimyeon' showed about 10~32 % of increase in yield as 7.08MT/ha and 26.7% of high amylose contents together with easy grinding property of 65.7% of high chalkiness ratio. The both of milled as well as brown rice of 'Saemimyeon' were well fit for processing properties in rice pasta where the contents of rice flour for rice pasta was 99% (1% of Tapioka starch was intermixed in to the rice flour). A spaghetti type for wet noodles and macaroni type for dry noodles were developed, respectively. Each of pasta were showed relatively more or less an equal quality and panel test compare to that of durum wheat pasta products. Finally, rice pasta products could suggest an alternative idea for a new rice processing items where rice noodles market was stagnant.

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추출조건에 따른 익모초 물추출물의 생리활성 비교 (Physiological properties of Leonurus sibiricus water extracts with different extraction condition)

  • 서지형;정용진
    • 한국식품저장유통학회지
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    • 제20권4호
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    • pp.592-596
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    • 2013
  • 익모초 가공을 위한 기본 추출조건을 확립하기 위하여 3가지 조건으로 익모초 물추출물(열수추출물(I), 고온고압-열수추출물(II), 습식분쇄-열수추출물(III))을 제조하고 이들의 생리적 특성을 비교하였다. 각 추출조건에 대한 수율은 13.02~15.90%로 유의적인 차이가 없었고, 총 폴리페놀 함량은 추출물(II)와 (III)에서 유의적으로 높았다. 전자 공여능에 대한 $IC_{50}$은 추출물(II)에서 가장 낮았고 그 뒤로 추출물(III) < 추출물(I)순으로 유의적인 차이를 나타내었으며, ABTS 라디칼 소거활성은 추출물(II)와 (III)에서 유의적으로 높았다. 아질산염 소거능은 추출조건간 유의적인 차이가 없었으며, ACE저해 활성은 고농도(5 mg/mL)의 추출물에 대해 추출물(I)보다 추출물(II)와 (III)에서 유의적으로 높았다.

Development of ginseng powder using high hydrostatic pressure treatment combined with UV-TiO2 photocatalysis

  • Lee, Hyunah;Shahbaz, Hafiz Muhammad;Ha, Namho;Kim, Jeong Un;Lee, Sang Jun;Park, Jiyong
    • Journal of Ginseng Research
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    • 제44권1호
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    • pp.154-160
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    • 2020
  • Background: Korean ginseng (Panax ginseng Meyer) powder is in rising demand because powder forms of foods are convenient to handle and are highly preservable. However, ginseng powder (GP) manufactured using the conventional process of air drying and dry milling suffers nutrient destruction and a lack of microbiological safety. The objective of this study was to prepare GP using a novel process comprised of UV-TiO2 photocatalysis (UVTP) as a prewashing step, wet grinding, high hydrostatic pressure (HHP), and freeze-drying treatments. Methods: The effects of UVTP and HHP treatments on the microbial population, ginsenoside concentration, and physiological characteristics of GP were evaluated. Results: When UVTP for 10 min and HHP at 600 MPa for 5 min were combined, initial 4.95 log CFU/g-fw counts of total aerobes in fresh ginseng were reduced to lower than the detection limit. The levels of 7 major ginsenosides in UVTP-HHP-treated GP were significantly higher than in untreated control samples. Stronger inhibitory effects against inflammatory mediator production and antioxidant activity were observed in UVTP-HHP-treated GP than in untreated samples. There were also no significant differences in CIELAB color values of UVTP-HHP-treated GP compared with untreated control samples. Conclusion: Combined processing of UVTP and HHP increased ginsenoside levels and enhanced the microbiological safety and physiological activity of GP.

리튬이차전지용 Si-M (M : Cr, Ni) 합금 음극의 미세구조와 전기화학적 특성 (Microstructures and Electrochemical Properties of Si-M (M : Cr, Ni) as Alloy Anode for Li Secondary Batteries)

  • 이성현;성재욱;김성수
    • 전기화학회지
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    • 제18권2호
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    • pp.68-74
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    • 2015
  • 본 실험에서는 리튬이차전지의 고용량 음극활물질로 주목받는 Si 합금의 부피팽창을 억제하기 위한 방법의 하나인 비활성-matrix상을 이용하고, 상태도를 이용하여 동일한 용량을 발현하는 Si계 이원계 합금 (Cr-Si, Ni-Si) 조성에서의 미세구조 및 전기화학적 특성을 비교/분석하였다. 급속응고공정(Rapid Solidification Process, Melt-spinning법)를 이용하여 동일조건하에서 리본 모양의 합금을 제작하였고, 제작된 리본합금은 동일조건에서 분쇄하여 X-선회절 (X-Ray Diffraction) 분석을 실시하였다. XRD 분석 결과, 상태도에서 예측된 것과 같이, 두 합금 모두 Si 상 및 비활성-matrix상($CrSi_2$$NiSi_2$)이 관찰되었으며, 이외의 제3의 상은 관찰되지 않았다. 또한, 주사전자현미경(SEM, Scanning Electron Microscope) 및 투과전자현미경-에너지분산분광법(TEM-EDS, Transmission Electron Microscopy - Energy Dispersive X-ray Spectroscopy)으로 미세구조를 살펴본 결과 Cr-Si 합금의 미세구조가 Ni-Si 합금보다 fine한 것을 알 수 있었고 이것은 상태도로부터 예측 가능하였다. 두 합금 조성에서 미세구조에 따른 전기화학적 특성을 비교 평가하기 위해 코인형 하프셀과 풀셀로 충방전 실험을 진행하였고 이와 별도로, 전극의 두께변화 측정이 가능하게 설계된 시험셀을 이용하여 반응 중 Si의 수축팽창을 측정하였다. coarse한 미세구조를 가진 Ni-Si 합금보다 fine한 미세구조를 갖는 Cr-Si 합금의 전극팽창이 비교적 잘 억제됨을 확인하였고, 충방전에 따른 수명 내구성도 우수함을 확인하였다. 이런 결과들로부터 합금의 조성에 따른 미세구조, 체적변화 및 전기화학적 열화와의 연관성을 유추할 수 있었다.

음료가공을 위한 쌀 품종별 품질 특성 비교 (Comparison of Quality Properties of Rice Cultivars for Beverage Processing)

  • 신동선;심은영;이석기;최혜선;박지영;우관식;김현주;조동화;오세관;한상익;박혜영
    • 한국식품영양학회지
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    • 제30권6호
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    • pp.1260-1267
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    • 2017
  • The properties of rice were studied on five rice cultivars (Ilpumbyeo, Samkwang, Goami-4, Dodamssal, and Thai rice), and employed two kinds of saccharification treatment methods (treatment I : rice shape, treatment II: grinding rice shape). Thai rice showed differences in width and length when compared to other cultivars of rice, and the Goami 4 had the lowest thousand-grain weight. The Goami4 and Dodamssal each showed high contents of amylose and resistant starch, and the water absorption rate was close to maximum at 90 minutes as well as the highest level of Goami 4 at all times. The qualities of highest water-binding capacity, solubility and swelling power was most significant in Thai rice. The lowest hardness level of wet rice resulted in the lowest hydration-related characteristics. High amylose content rice, in particular, showed low sugar content and slightly increased sugar content as the saccharification process improved (treatment II). On the other hand, high amylose cultivars had the same high degree of hardness as boiled rice. From these results, the Dodamssal was found to have the lowest viscosity at all temperatures but highest viscosity during the saccharification process, suggesting it may be successfully implemented as a thickener in rice beverage processing. The purpose of this study was to attempt to provide basic data on the development of rice beverage manufacturing technology, based upon the quality characteristics related to beverage processing of rice cultivars.

테스토스테론-유도 양성전립선비대증에서 나노화 벌 화분의 효능 연구 (Beneficial Effects of Nano-sized Bee Pollen on Testosterone-induced Benign Prostatic Hyperplasia in Rodents)

  • 박지아;편해인;소수정;이승현;이승민;서화진;강재선;최윤식;정일경
    • 생명과학회지
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    • 제28권4호
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    • pp.465-471
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    • 2018
  • 벌 화분은 오랫동안 전 세계적으로 이용되어 온 대체요법 중 하나이다. 벌 화분은 항진균 및 항균작용, 항암작용, 면역조절, 그리고 세포의 증식 등 다양한 생리활성을 갖고 있는 것으로 알려져 있다. 본 연구는 설치류를 이용하여 벌 화분의 양성전립선비대증의 개선 효과를 밝히기 위해 진행되었다. 벌 화분은 활성 성분의 추출률을 극대화하고, 생체 흡수율을 높이기 위하여 나노 크기로 분쇄하여 이용하였다. 먼저, 나노 크기의 벌 화분은 만성 testosterone 투여에 의한 전립선 크기 증가를 유의하게 완화하였다. 게다가 나노 크기의 벌 화분은 혈중 전립선 특이 항원의 농도를 뚜렷하게 감소시켰다. 흥미롭게도 나노 크기의 벌 화분은 testosterone에 의한 혈중 prostaglandin $E_2$ 증가에는 유의한 영향을 미치지 않았다. 이러한 나노 크기 벌 화분의 약리 효능은 dutasteride의 효과와 유사하였다. 마지막으로 나노 크기의 벌 화분은 androgen-반응성 인간 전립선 샘암종 세포인 LNCaP 세포의 손상을 유도하지 않았다. 이러한 결과를 종합하면, 나노화 된 벌 화분은 양성전립선비대증의 치료에 대체요법으로 이용될 수 있을 것으로 기대된다.

태양광 폐모듈 실리콘을 재활용한 메커니컬 실 제조공정의 환경성평가 (Environmental Impact Evaluation of Mechanical Seal Manufacturing Process by Utilizing Recycled Silicon from End-of-Life PV Module)

  • 신병철;신지원;권우택;최준철;선주형;장근용
    • 청정기술
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    • 제28권3호
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    • pp.203-209
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    • 2022
  • 본 연구에서는 태양광 폐모듈 해체과정에서 회수한 실리콘을 재활용하여 기계구조용 메커니컬 실을 제조하는 공정에 대해 전과정평가 방법에 의한 환경성평가를 수행하였다. 재활용 실리콘은 고순도 정제 후 탄소와 반응시켜 β-SiC 입자로 합성하고 압축 성형, 소결 및 열처리를 거쳐 제품을 생산한다. 현장 데이터 수집 및 환경부 LCI DB를 활용하여 각 단계별로 자원고갈, 산성화, 부영양화, 지구온난화, 오존층파괴, 광화학산화물 등 6개 영역의 환경영향을 산정하였다. 영향범주 별 환경영향은 지구온난화 45 kg CO2, 광화학산화물 2.23 kg C2H4으로 크게 나타났으며 가중화 분석결과 광화학산화물, 자원고갈 및 지구온난화에 의한 환경영향이 98.7%로 높은 기여도를 차지하였다. 원료 실리콘과 탄소를 미분쇄 혼합하는 습식공정과 β-SiC 과립화 공정이 주요한 환경영향 유발요인이므로 건식공정으로 전환 및 대기 배출되는 용매는 회수하여 재이용하는 시스템으로 개선이 필요하다. 폐모듈 실리콘의 재활용에 의해 자원고갈의 영향은 53.9%, 지구온난화는 60.7% 감소하며 가중화 결과 전체적인 환경영향이 27% 감소하는 것으로 분석되어 폐모듈 재활용은 자원절약과 탄소중립 실현의 주요 수단이 될 수 있음을 LCA 분석으로 확인하였다.