• Title/Summary/Keyword: Plant specimens

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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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    • v.20 no.4
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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.

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

  • 권영호;백명종;이보근;박칠림
    • Proceedings of the Korea Concrete Institute Conference
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    • 1994.10a
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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
    • Korean Journal of Plant Taxonomy
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    • v.52 no.3
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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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    • v.32 no.3
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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.

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

  • Kim, Ki-Woo
    • Applied Microscopy
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    • v.41 no.4
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    • pp.223-228
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    • 2011
  • White light scanning interferometry has been employed to analyze surface features of diverse specimens. Long established in the field of materials engineering, the technique provides quantitative three-dimensional data as well as qualitative morphological images. It uses white light that is split and reflected from a reference mirror and an object. Merged together, the light generates interference patterns representing topographical contours of the object surface. The amplitude of the z-axis data is differentiated by gray scale. The technique allows the rapid, noncontact, and wide-field measurements for morphometry of biological specimens including chondrocytes, tooth enamel, and plant leaves. Quantification of the dimension of surface structures such as width, length, and elevation angle could be achievable by white light scanning interferometry. The light reflection from plant leaves has been assumed to be sufficient for the technique. Without special specimen preparations like conductive metal coating, the technique can be increasingly used for quantitative three-dimensional surface measurements of biological specimens.

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

  • Lee, Hye Jeong;Lee, You Mi;Park, Su Hyun;Kang, Young Sik
    • Korean Journal of Plant Taxonomy
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    • v.38 no.3
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    • pp.333-343
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    • 2008
  • Two newly naturalized species were recorded from Gangwon-do and Jeju-do. Among them, numerous populations of Hieracium caespitosum (Asteraceae) were found in 2006 along the road near the military area at, Mt. Dosolsan, Yanggu-gun, Gangwon-do. The other species, Trifolium incarnatum (Fabaceae) was widespread and found at various locations including Jeongsil and Woo-do in Jeju-si, Jeju-do and Gasioreum, Daejeong-eup, Seoguipo-si, Jeju-do and Daehandawon Plantation in Hoecheon-myon, Boseong-gun, Jeonranam-do in 2008. Hieracium caespitosum was found to be distinguished from the allied species, H. umbellatum in the same genus, by a lot of capitula and a well developed cluster of basal leaves during the flowering time. Trifolium incarnatum can be distinguished from other species in the same genus by an erect form, long inflorescence and deep-red flowers.

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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    • v.33 no.10
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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.

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" ("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)

  • Eom, Hyun-Joo;Chang, Chin-Sung;Kim, Hui
    • Journal of Korean Society of Forest Science
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    • v.99 no.4
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    • pp.447-469
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    • 2010
  • The recent publications of two major works from Ministry of Environment and Korea National Arboretum (Type specimens collected from Korea at the herbarium of the University of Tokyo, five volumes) and National Institute of Biological Resources (Korean type specimens deposited in foreign herbaria and museums, two volumes excluding other animal groups) on Korean vascular plants have resulted in discrepancies needing either correction or clarification. The former published the results of a portion of T. Nakai's collections deposited at TI, while the latter produced the results about collections of G. Koidzumi's, J. Ohwi's, and S. Kitamura's at Kyoto University and of E. H. Wilson's and H. Leveille's at Harvard University. Consequently some omissions, discrepancies, and conflicts resulted, such as the inclusion of conflicting designations of lectotype, isotype, syntype or holotype, erroneous citations of publications, and misinformation. Suh et al.'s publications about type specimens of Korean plants deposited at TI showed 47 conflicting typifications and 20 typographical and other errors. Type information offered by Yim et al. were discussed, and 75 conflicting typification and 30 typographical and other errors from these two volumes were also brought to notice. It is clear that Suh et al. and Yim et al. merely provided type information without consulting original description of each plant species. It is apparent that all these conflicting designation of types, erroneous citations of publications, and other types of misinformation were as a result of the disregard of original citation and the ignorance of basic type concept.

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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    • v.25 no.3
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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.

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

  • Kwon, Sang-Hyuk;Yun, Sei-Young;Lee, Kyung-Tae;Park, Hee-Juhn
    • Korean Journal of Pharmacognosy
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    • v.31 no.1
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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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