• 제목/요약/키워드: Plant specimens

검색결과 456건 처리시간 0.031초

Cyclic loading test of abnormal joints in SRC frame-bent main building structure

  • Wang, Bo;Cao, Guorong;Yang, Ke;Dai, Huijuan;Qin, Chaogang
    • Earthquakes and Structures
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    • 제20권4호
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    • pp.417-430
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    • 2021
  • Due to functional requirements, SRC column-RC beam abnormal joints with characteristics of strong beam weak column, variable column section, unequal beam height and staggered height exist in the Steel reinforced concrete (SRC) frame-bent main building structure of thermal power plant (TPP). This paper presents the experimental results of these abnormal joints through cyclic loading tests on five specimens with scaling factor of 1/5. The staggered height and whether adding H-shaped steel in beam or not were changing parameters of specimens. The failure patterns, bearing capacity, energy dissipation and ductile performance were analyzed. In addition, the stress mechanism of the abnormal joint was discussed based on the diagonal strut model. The research results showed that the abnormal exterior joints occurred shear failure and column end hinge flexural failure; reducing beam height through adding H-shaped steel in the beam of abnormal exterior joint could improve the crack resistance and ductility; the abnormal interior joints with different staggered heights occurred column ends flexural failure; the joint with larger staggered height had the higher bearing capacity and stiffness, but lower ductility. The concrete compression strut mechanism is still applicable to the abnormal joints in TPP, but it is affected by the abnormal characteristics.

열병합발전소 플라이애쉬의 특성 및 활용방안에 관한 실험적 연구 -고강도 콘크리트를 중심으로- (AN EXPERIMENTAL STUDY ON THE PROPERTIES & APPLICATION FOR FLY ASH OF CONBINED HEAT POWER PLANT - FOCUSSED HIGH STRENGTH CONCRETE -)

  • 권영호;백명종;이보근;박칠림
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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    • pp.211-216
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    • 1994
  • This study dealt with the properties for fly ash of conbined heat power plant and application for concrete industry. For this purpose, fly ash sampled Ulsan conbined heat power plant and analyzed for physical and chemical properties. As analyzed results of fly ash, contents of $SiO_ and Al_O_ $in the fly ash of Ulsan were less than those of Thermo-electric power plant(Boryuing), but contents of CaO were tem times as much as those of Boryung, because of these differences, it is expected that pozzolanic activity of concrete using fly ash of Ulsan will be different from another fly ash. Concrete specimens were tested to evaluate concrete preformance when 10 to 50 percent of the portland cement by weight in the concrete mix was replaced with fly ash of conbined heat power plant. As test results, workability and consideration in the fresh concrete were increased and concrete strength was showed more than 400kg/$\textrm{cm}^2$ for the required age. This study would be provided valuable data for the practical utilization of fly ash(conbined heat power plant). In the future, properties of fly ash concrete including long term strength, elapsed time, pozzolanic activity, modulus of elasticity, sulfate resistance, shrinkage, freeze-thaw durability and so on will be studied.

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Nineteen new records of plant species including two new genera recorded from the Bhutan Himalayas

  • DORJI, Rinchen;PHUENTSHO, Phuentsho;DORJI, Kencho;TSHEWANG, Sangay;WANGDI, Phuntsho;TOBGAY, Kezang;GYELTSHEN, Nima;GYELTSHEN, Choki
    • 식물분류학회지
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    • 제52권3호
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    • pp.173-183
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    • 2022
  • Through the collection of herbarium specimens in Bhutan over the years, new plant species are discovered nearly annually. Thus, this paper reports two new genera and 19 new records of flowering plant species from Bhutan. The new genera include Eurycorymbus of the family Sapindaceae and Homalium of the family Salicaceae. The new records of plant species are Eranthemum erythrochilum (Acanthaceae), Hemidesmus indicus (Apocynaceae), Ilex umbellulata (Aquifoliaceae), Canarium strictum (Burseraceae), Ehretia acuminate (Boraginaceae), Vaccinium sikkimense (Ericaceae), Nothapodytes foetida (Icacinaceae), Machilus edulis (Lauraceae), Grewia asiatica (Malvaceae), Hibiscus fragrans (Malvaceae), Cipadessa baccifera (Meliaceae), Baccaurea javanica (Phyllanthaceae), Canthiumera glabra (Rubiaceae), Homalium napaulense (Salicaceae), Eurycorymbus cavaleriei (Sapindaceae), Acmella radicans (Asteraceae), Silene latifolia (Caryophyllaceae), Cleome rutidosperma (Cleomaceae), and Cuphea carthagenensis (Lythraceae). Morphological determinations of the genera and species were carried out at the National Herbarium (THIM) of the National Biodiversity Centre of Bhutan. Brief descriptions of the species, phenology, and photo plates are provided in this annotated checklist.

Adding to the freshwater red algal diversity in North America: Lympha mucosa gen. et sp. nov. (Batrachospermales, Rhodophyta)

  • Evans, Joshua R.;Chapuis, Iara S.;Vis, Morgan L.
    • ALGAE
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    • 제32권3호
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    • pp.171-179
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    • 2017
  • The strictly freshwater red algal order Batrachospermales has undergone numerous taxonomic rearrangements in the recent past to rectify the paraphyly of its largest genus Batrachospermum. These systematic investigations have led to the description of new genera and species as well as re-circumscription of some taxa. Specimens collected from two locations in the southeastern USA were initially identified as being allied to Batrachospermum sensu lato, but could not be assigned to any recognized species. Representative rbcL (plastid) and COI-5P (mitochondrion) sequences showed these specimens to be similar to each other and not closely matching the previously published sequence data for other Batrachospermum taxa. Comparison of sequence variation and morphology with a broader range of batrachospermalean taxa resulted in the proposal of a new monotypic genus Lympha mucosa gen. et sp. nov. to accommodate these specimens. Lympha mucosa is sister to members of a newly described genus Volatus, but the two genera are easily distinguished based on straight versus curved, twisted or spirally coiled carpogonial branch, respectively. This new taxon has morphological similarities to Batrachospermum sections Turfosa and Virescentia, but can be differentiated based on genetic divergence in rbcL and COI-5P as well as a combination of morphological characters: dense, compressed whorls, axial carposporophytes with a single type of gonimoblast filament; cortication of the main axis closely appressed; and short, straight carpogonial branch arising from the pericentral cell and carpogonia with unstalked, lanceolate trichogynes. This new taxon adds to the freshwater red algal diversity of the southeastern USA, a region already known for biodiversity and high endemism of the aquatic flora and fauna. It is also a relevant new addition to the taxonomic knowledge of the freshwater red algal Batrachospermales.

백색광 주사간섭계의 생물학적 응용 (Biological Applications of White Light Scanning Interferometry)

  • 김기우
    • Applied Microscopy
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    • 제41권4호
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    • pp.223-228
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    • 2011
  • 백색광 주사간섭계는 다양한 시료의 표면 특성을 분석하기 위하여 널리 활용되고 있다. 이 기법은 재료공학 분야에서 오래 전부터 이용되었으며 정성적인 형상 이미지 이외에도 정량적인 3차원 결과를 제공한다. 이 기법에서는 백색광을 광원으로 이용하는데, 기준면과 측정면에서의 반사광을 합쳐서 형성되는 간섭신호를 형태 정보로 활용한다. z축 결과인 고도는 회색수준으로 구분되어 제시된다. 이 기법을 통하여 대영역으로 생물 시료를 신속하고 비파괴적으로 형태를 계측할 수 있다. 연골세포, 치아 법랑질, 식물 잎을 대상으로 적용한 사례가 있다. 특히 표면 구조물의 폭, 길이, 경사각과 같은 특성도 이 기법을 통하여 정량화할 수 있다. 이 기법을 적용하기 위하여 일정 수준의 반사도가 필요한데, 식물 잎에서의 반사도는 그 요건을 충족하였다. 전도성 금속의 코팅 등 부가적인 시료 전처리가 필요 없으므로 이 기법을 통한 생물 시료의 정량적 측정이 더욱 증가할 것으로 예상한다.

한국 미기록 귀화식물인 유럽조밥나물(Hieracium caespitosum Dumort.)과 진홍토끼풀(Trifolium incamatum L.) (Newly recorded naturalized species in Korea, Hieracium caespitosum and Trifolium incamatum)

  • 이혜정;이유미;박수현;강영식
    • 식물분류학회지
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    • 제38권3호
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    • pp.333-343
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    • 2008
  • 강원도 양구군 도솔산과 제주도에서 2종류의 미기록 귀화식물을 발견하였다. Hieracium caespitosum Dumort.는 양구군 도솔산에서 분포가 확인되었으며 조밥나물과 비교하여 두화의 수가 많고, 개화시기에도 근생엽이 달려 있는 특징이 있으며, 유럽이 원산지여서 유럽조밥나물로 신칭하였다. Trifolium incarnatum L.은 제주도 정실, 우도, 대정 가시오름 및 전라남도 보성 녹차단지 주변 등 여러 곳에서 발견되었으며 토끼풀속의 다른 식물들과는 꽃이 진홍색이고, 화서가 길게 발달하며 식물체가 직립하는 등의 특징으로 구별된다.

Bacterial Microbiome Differences between the Roots of Diseased and Healthy Chinese Hickory (Carya cathayensis) Trees

  • Xiao-Hui Bai;Qi Yao;Genshan Li;Guan-Xiu Guan;Yan Fan;Xiufeng Cao;Hong-Guang Ma;Mei-Man Zhang;Lishan Fang;Aijuan Hong;Dacai Zhai
    • Journal of Microbiology and Biotechnology
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    • 제33권10호
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    • pp.1299-1308
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    • 2023
  • Carya cathayensis is an important economic nut tree that is endemic to eastern China. As such, outbreaks of root rot disease in C. cathayensis result in reduced yields and serious economic losses. Moreover, while soil bacterial communities play a crucial role in plant health and are associated with plant disease outbreaks, their diversity and composition in C. cathayensis are not clearly understood. In this study, Proteobacteria, Acidobacteria, and Actinobacteria were found to be the most dominant bacterial communities (accounting for approximately 80.32% of the total) in the root tissue, rhizosphere soil, and bulk soil of healthy C. cathayensis specimens. Further analysis revealed the abundance of genera belonging to Proteobacteria, namely, Acidibacter, Bradyrhizobium, Paraburkholderia, Sphaerotilus, and Steroidobacter, was higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. In addition, the abundance of four genera belonging to Actinobacteria, namely, Actinoallomurus, Actinomadura, Actinocrinis, and Gaiella, was significantly higher in the root tissues of healthy C. cathayensis specimens than in those of diseased and dead trees. Altogether, these results suggest that disruption in the balance of these bacterial communities may be associated with the development of root rot in C. cathayensis, and further, our study provides theoretical guidance for the isolation and control of pathogens and diseases related to this important tree species.

"Type Specimens Collected from Korea at the Herbarium of the University of Tokyo"와 "Korean Type Specimens Deposited in Foreign Herbaria and Museums"의 오류에 대한 비평 (A Critical Review of "Type Specimens Collected from Korea at the Herbarium of the University of Tokyo" and "Korean type Specimens Deposited in Foreign Herbaria and Museums")

  • 엄현주;장진성;김휘
    • 한국산림과학회지
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    • 제99권4호
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    • pp.447-469
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    • 2010
  • 최근 환경부와 국립수목원에서 발간한 한반도의 관속식물의 기준표본 관련 자료인 Type specimens collected from Korea at the herbarium of the University of Tokyo (Suh et al.)와 국립생물자원관에서 발간한 Korean type specimens deposited in foreign herbaria and museums(해외기관소장 한반도 생물자원기준표본화보집, Yim et al.) 내용에 오류 확인과 정정이 필요하여 본 연구를 수행하였다. 전자에 해당되는 자료는 동경대학(東京大學) 총합연구박물관(總合硏究博物館)(TI)에 소장되어 있는 T. Nakai의 수집품을 정리한 것이며, 후자의 경우는 G. Koidzumi, J. Ohwi, S. Kitamura 등 경도대학(京都大學) 연구자와 하버드대학 E. H. Wilson, H. Leveille의 수집품을 정리한 내용이다. 두 간행물은 lectotype, isotype, syntype 또는 holotype 등의 잘못된 지정과 기재문 및 관련 정보에 대한 오류 등을 범하고 있다. 특히, Suh et al.은 TI에 소장되어 있는 한반도 식물의 기준표본을 정리한 출판물에서는 47개의 기준표본 지정 오류와 20개의 지명 및 문헌 등의 기재에 오류가 있었고, Yim et al.은 2권의 책자에 정리한 기준표본 정보는 75개의 지정 오류와 30개의 지명 및 문헌 등 기재 오류가 확인되었다. Suh et al.과 Yim et al.은 기재문 확인 연구가 없이 단순히 기준표본에 대한 정보만을 제공하고 있어 이런 기준 표본 오류가 발생하였다. 또한, 기재문 및 다른 관련 정보에 대한 오류는 원기재문의 미확인과 기준표본에 대한 기본적인 개념부재가 원인이라고 판단된다.

Occurrence of Goat's-Beard Powdery Mildew Caused by Podosphaera ferruginea in Korea

  • Lee, Sang-Yeob;Kim, Wan-Gyu;Hong, Sung-Kee;Lee, Young-Kee
    • The Plant Pathology Journal
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    • 제25권3호
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    • pp.299-301
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    • 2009
  • Powdery mildew symptoms were frequently on plants of goat's-beard (Aruncus dioicus var. kamtschaticus) found cultivated in the island Ulleungdo in June 2008. The symptoms appeared as powdery mycelial colonies and dark brown cleistothecia on leaves, petioles, stems and budding flowers of the plant. Incidence of the disease was as high as 50-80% in the goat's-beard fields. Specimens of the diseased plants were collected and examined for morphological characteristics of the causal fungus. On the basis of morphological characteristics of the conidial stage and the teleomorph, the fungus was identified as Podosphaera ferruginea. This is the first report of goat's-beard powdery mildew caused by Podosphaera ferruginea in Korea.

물레나물로부터 Steroid 및 Flavonoid 성분의 분리 (Isolation of Steroids and Flavonoids from the Herbs of Hypericum ascyron L.)

  • 권상혁;윤세영;이경태;박희준
    • 생약학회지
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    • 제31권1호
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    • pp.39-44
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    • 2000
  • A sterol mixture, 3-O-glucosides of these sterols, 6'-O-fattyacyl ester of these sterol glucosides, kaempferol, quercetin and isoquercitrin were isolated from the whole plants of Hypericum ascyron L. The sterols were found to be a mixture of ${\beta}-sitosterol$, campesterol and stigmasterol by GC-MS. The kinds of fatty acids linked at 6'-OH of sterol glucoside ester mixture were shown to be palmitic acid, stearic acid, oleic acid and linoleic acid by GC-MS. Three flavonoids were identified by spectroscopic methods and comparisons of mixed mp and co-TLC with authentic specimens.

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