• 제목/요약/키워드: granulate

검색결과 37건 처리시간 0.031초

한강하류의 환경학적 연구 -VII. 식물플랑크톤군집의 장기간 변화와 전망- (Environmental Studies in the Lower Part of the Han River -VII. Long Term Variations and Prospect of the Phytoplankton Community-)

  • 이진환;정승원
    • ALGAE
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    • 제19권4호
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    • pp.321-327
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    • 2004
  • The literature review on the dynamics of the phytoplankton communities in terms of species composition, standing crops, abundant species and dominant species in the lower part of the Han River from 1940s to 2000s was conducted for the prospective prediction of their succession patterns. Total of 326 taxa were identified and they belonged to 47 blue-green algae, 139 green algae, 12 euglenoids, 126 diatoms, 6 din flagellates and 2 silicoflagellates. Composition of phytoplankton communities were 83.6% diatoms, 10.5% blue-green algae and 5.3% green algae in the middle of 1960s, whereas those were 43.2% diatoms, 40.7% green algae and 13.6% blue-green algae in the 1990s. Before 1990s, Synedra ulna, Melosira varians, Cymbella tumida, Synedra acus, Cymbella ventricosa, Navicula cryptocephala, Nitzschia palea, Aulacoseira granulata, Gomphonema parvulum and Cymbella affinis were most frequent, while those after 1990 were Asterionella formosa, Asterionella gracillima, Aulacoseira granulate, Aulacoseira granulata var. angustissima, Chlorella vulgare, Fragilaria crotonensis and Synedra ulna. Phytoplankton blooms were frequent from winter to the late spring and rare in summer due to heavy rain and discharge. Seasonal variations of the dominant species were fairly obvious; Asterionella gracillima and Aulacoseira granulata in spring, Aulacoseira granulate and Aulacoseira granulate var. angustissima in summer and autumn, Asterionella gracillima and Stephan discus hantzschii in winter. Recently blue-green algae, Microcystis, Aphanocapsa, Dactylococcopsis have been more abundant than those of the previous reports. Based on the current situations, Stephan discus hantzschii f. tennis, Asterionella gracillima, Aulacoseira granulate and blue-green algae will be more abundant and blooms of those species will be more frequent.

노루궁뎅이버섯 추출물을 이용한 제형가공 및 품질특성 (Form Manufacturing and Quality Characteristics using Extracts from Hericium erinaceus)

  • 박수정;홍주헌;윤광섭;최용희
    • 한국식품저장유통학회지
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    • 제13권5호
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    • pp.569-573
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    • 2006
  • 생리활성물질을 다량 함유하고 있는 노루궁뎅이 버섯을 효과적으로 섭취하기 위하여 분말, 과립, 타블렛, 캅셀 등 다양한 제형으로 가공하였으며 이들의 품질특성을 비교하였다. 수분함량은 분무건조 분말, 과립, 타블렛 순으로 그 값은 각각 4.37%, 3.78%, 3.43%으로 나타났으며 총당 함량은 분무건조 분말이 19.14 g%로 가장 낮은 함량을 보여주었고 단백질 함량은 분무건조 분말, 과립, 타블렛 순으로 그 값은 각각 4.39 g% 1.04g%, 0.75g% 임을 확인하였다. 제형별 수분결합지수는 과립 및 타블렛 제품이 분무건조분말 제품보다 수분결합지수가 낮은 것으로 나타났는데 이는 과립과 타블렛 제조시 가용성의 탄수화물 제제인 부형제가 많이 첨가되었기 때문인 것으로 판단된다. 전체적인 색상을 나타내는 hue angle은 분무건조 분말이 $85.50^{\circ}$, 과립이 $95.37^{\circ}$, 타블렛이 $94.67^{\circ}$로 나타났다. 저장안정성을 확인하기 위한 제형별 흡습특성은 분무건조 분말이 가장 높은 흡습성을 보였으며 과립, 타블렛 순으로 뚜렷한 차이를 나타내어 분무건조 분말보다는 타블렛 형태로 제조한다면 저장성 면에서 더 우수한 제품을 얻을 것으로 사료된다.

Treatment of pigs with enrofloxacin via different oral dosage forms - environmental contaminations and resistance development of Escherichia coli

  • Janssen, Paula;Barton, Gesine;Kietzmann, Manfred;Meissner, Jessica
    • Journal of Veterinary Science
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    • 제23권2호
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    • pp.23.1-23.15
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    • 2022
  • Background: Antibacterial agents play important roles in the treatment of bacterial infections. However, the development of antimicrobial resistance (AMR) and carry-over of substances into the environment are several problems arising during oral treatment of bacterial infections. We assessed AMR development in commensal Escherichia coli (E. coli) in enrofloxacin treated and untreated animals. In addition, we examined fluoroquinolone in the plasma and urine of treated and untreated animals, and in sedimentation dust and aerosol. Methods: In each trial, six pigs were treated with enrofloxacin via powder, granulate or pellet forms in two time periods (days 1-5 and 22-26). Four pigs served as untreated controls. The minimum inhibitory concentration (MIC) was determined to evaluate AMR development. Analysis of enro- and ciprofloxacin was performed with high performance liquid chromatography. Results: Non-wildtype E. coli (MIC > 0.125 ㎍/mL) was detected in the pellet treated group after the first treatment period, whereas in the other groups, non-wildtype isolates were found after the second treatment period. E. coli with MIC > 4 ㎍/mL was found in only the pellet trial. Untreated animals showed similar susceptibility shifts several days later. Bioavailability differed among the treatment forms (granulate > pellet > powder). Enro- and ciprofloxacin were detected in aerosols and sedimentation dust (granulate, powder > pellet). Conclusions: This study indicates that the kind of the oral dosage form of antibiotics affects environmental contamination and AMR development in commensal E. coli in treated and untreated pigs.

Innovative Materials and Production Techniques for Sinterforged PM Aluminium Components with Improved Performance

  • Neubing, Hans-Claus;Ichikawa, Junichi;Gradl, Johann
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.710-711
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    • 2006
  • High strength PM aluminium alloys Al-Zn-Mg-Cu (7075 type) were studied by using commercially available powder blends and the sinter-forging technique for component production. Principal areas of focus include the response to PM processing, micro structural assessment and material properties of Aluminium sinter forged products. Green preforms are successfully sintered to near full density by solid-supersolidus liquid phase sintering. Sinter forging method can produce components with net shape and mechanical characteristics of the material have improved greatly. Properties of this new PM Al-alloy were found to be reproducible in an industrial production environment.

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진양호와 합천호의 식물플랑크톤상에 관한 연구 (A Study on Phytoplankton Flora in Chinyang Lake and Hapchun Lake)

  • 김종원;이학영;김맹기;조인숙
    • 한국환경과학회지
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    • 제2권4호
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    • pp.367-371
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    • 1993
  • Phytoplankton flora of Chinyang Lake and Hapchun Lake were studied. A total of 161 species(Chinyang Lake, 135 species; Hapchun Lake, 80 species) were identified. The major species of two lakes were Melosira granulate var. angustissima and M. italica. As the bloom causing species, Microcystis aeruginosa, Ceratium hirundinella, and Peridinium sp. were identified. The chlorophyll a concentration of Chinyang Lake was higher than Hapchun Lake.

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산업부산물을 결합재로 이용한 콘크리트의 물리적 특성 (Physical Properties of Concrete using Industrial By-Products as Binder)

  • 강내민;문경주;소양섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.79-82
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    • 2003
  • In this study, non-sintering cement is produced by only blending granulate blast furnace slag with phosphogypsum as main materials, and small amounts of hydrate lime or waste lime as activators. This paper was investigated physical properties of fresh concrete and hardened concrete using non-clinker cement according to various mixing ratio. Results obtained from this study have shown that concrete using non-clinker cement could be used for structural concrete and concrete 2th production as binder.

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산업부산물을 이용한 무 클링커 시멘트의 기초적 특성 (Basic Properties of Non-Clinker Cement Using Industrial By-Products)

  • 문경주;소양섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.11-16
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    • 2002
  • The production of Portland cement involves maximum use of resources and energy, which leads to destruction of tile ecological environment, raising in serious environmental issues such as acid rain and the greenhouse effect. In order to combat the arising problems associated with Portland cement, it thus is necessary that a non-clinker cement should be developed. In this study, non-clinker cement is produced by blending granulate blast furnace slag with phosphogypsum as main materials, and small amounts of hydrate lime or waste lime as activators. This paper aims to investigate compressive strength according to various condition of mixing ratio, blame, W/C ratio and curing temperature. Compressive strength of non-clinker cement increases continuously according to increase in curing age and blain. Although the compressive strength is fairly comparable to that of OPC in the early curing age, it reaches a higher lever in the later age than that of OPC due to the optimum mixing ratio and the continuous reaction of slag and phosphogypsum. Results obtained from this study have shown that non-clinker cement could be used as a replacement of OPC.

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회동수원지의 식물플랑크톤군집에 관하여 (On the phytoplankton community in Hoe-dong Reservoir)

  • 문성기;홍채규;정종문
    • 한국환경과학회지
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    • 제4권3호
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    • pp.167-176
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    • 1995
  • A study on phytoplankton community was carried out from June, 1992 to May, 1993 at selected stations in Hoedong Reservoir. The phytoplankton are identified as 176 taxa including 5 phylum, 67 genera. The important species in this reservoir were Asterionella formosa, C meneghiniana, Dictyosphaerium plilchellum, Fragilaria crotonensis, Melosira distans, M grantulata, M. granulata var. angustissima, M. granulate var. angntissima f. spirdis, Micractinium pussillum, Microcystis aeruginosa, Pundorina morn, Pediastrum boryanum, P. duplex, Peridinium sp., Scenedesmus quadriauda, Synedra acus, S. rumpens and S. ulna. The causative species of water bloom were identified as Microcystis aeruginsa, Trahellomonas hispida, Ceratium hirwdinella, Peridinium sp., Melosira italica, Staurastrum dorsidentiferum var. onatum in the area. During the study periods standing crcps of phytoplankton were maximum in August, 1992 and minimum in December 1992. The species dominance index and diversity index were ranged 24.7-99.9, 0.001-3.06, respectively. Key Words : phytoplankton community, causative species of water bloom, standing crops. dominance index, species diversity index.

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무가압분말 충전성형법에 의한 다공성 세라믹스의 제조 및 특성 : II. 뮬라이트 & 코디어라이트 (The Fabrication and Characteristics of Porous Ceramics by Pressureless Powder Packing Forming Method ; II, Mullite & Cordierite)

  • 박정현;황명익;김동희;최환욱;김용남
    • 한국세라믹학회지
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    • 제36권6호
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    • pp.671-678
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    • 1999
  • Porous ceramics were fabricated from pressureless powder packing forming method using mullite and cordierite powders granulate by spray drying. The bending strength and shrinkage of porous ceramics were increased and their porosity were decreased with increasing temperature. It showed homogeneous distribution of 2$\mu\textrm{m}$ intergranular pores of mullite at 1400$^{\circ}C$, 2.5$\mu\textrm{m}$ intergranular pores of cordierite at 1300$^{\circ}C$ respedtively. Above that temperature intragranular particles were sintered and sintering by intergranular necking was extremely proceeded. In the test of thermal shock resistance sudden decrease of bending strength to $\Delta$T was not shown because intergranular large pore prevented sudden crack propagation.

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