• Title/Summary/Keyword: Knowledge Structures

Search Result 728, Processing Time 0.035 seconds

Chemical Constituents of Nelumbo nucifera Seeds

  • Rho, Taewoong;Yoon, Kee Dong
    • Natural Product Sciences
    • /
    • v.23 no.4
    • /
    • pp.253-257
    • /
    • 2017
  • The phytochemical study for the extract of Nelumbo nucifera (Nymphaceae) seeds has led to the isolation of ten compounds including five simple phenolic compounds, two indole derivatives, a flavonoid glycoside, two abscisic acid derivatives. The interpretation of 1D and 2D NMR and ESI-Q-TOF-MS spectroscopic data revealed the chemical structures of isolates to be p-hydroxybenzoic acid (1), protocatechuic acid (2), (E)-p-coumaric acid (3), (E)-ferulic acid (4), (E)-sinapate-4-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (5), tryptophan (6), 3-indoleacetic acid (7), isoschaftoside (8), dihydrophaseic acid (9), dihydrophaseic acid 3'-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (10). To the best of our knowledge, 1 - 5 and 7 were identified for the first time from N. nucifera seeds, and the presence of dihydrophaseic acid (9) and its glucoside (10) were demonstrated secondly in this plant.

Secondary Metabolites Produced by Endophytic Fungus, Arthrinium phaeospermum (내생균 Arthrinium phaeospermum이 생산하는 이차대사산물)

  • Xia, Xuekui;Shim, Sang Hee
    • Korean Journal of Pharmacognosy
    • /
    • v.47 no.3
    • /
    • pp.217-221
    • /
    • 2016
  • Endophytic fungi have yielded a variety of secondary metabolites so far. In the course of the project to find bioactive secondary metabolites from cultures of endophytic fungi, an isolate of Arthrinium phaeospermum (JS 0567) was selected for chemical investigation. A large scale culture of this strain in rice media was extracted with an organic solvent and the extract was subjected to a serious of chromatography, which led to six metabolites. Their chemical structures were elucidated as 2,3,6,8-tetrahydroxy-1-methylxanthone(1), 2,3,4,6,8-pentahydroxy-1-methylxanthone(2), 3,4,6,8-tetrahydroxy-1-methylxanthone(3), 3,6,8-trihydroxy-1-methylxanthone(4), 2,4,2',4',6'-pentahydroxy-6-methylbenzophenone(5), and 5,7-di hydroxy-3-methylphthalide(6) on the basis of spectroscopic data. To the best of our knowledge, this is the first study on the secondary metabolites from Arthrinium phaeospermum.

Chemical Constituents from Non-polar Fraction of the Fruiting Bodies of Hericium erinaceum (노루궁뎅이 버섯 자실체의 비극성 분획에서 분리된 성분들)

  • Li, Wei;Shim, Sang Hee;Kim, Young Ho
    • Korean Journal of Pharmacognosy
    • /
    • v.48 no.4
    • /
    • pp.280-284
    • /
    • 2017
  • Lion's Mane Mushroom, Hericium erinaceum, is a traditional edible mushroom widely used in culinary applications. It has been also used as a medicine in East Asian countries due to its various biological activities. Chemical investigation of fruiting bodies of this mushroom afforded many aromatic compounds, which were mostly isolated from polar fraction of its extracts. Herein we tried to investigate non-polar compounds from the extracts of this mushroom. $CHCl_3$-soluble fraction of the extracts was subjected to chemical investigation, which resulted in isolation of four compounds. Their chemical structures were elucidated as ircicerebroside (1), cortenuamide A (2), 1-D-arabinitol-monolinoleate (3), and cinnamic acid (4) on the basis of spectroscopic data. To the best of our knowledge, this is the first report of compounds 1, 2, and 4 from Hericium erinaceum.

Quinolone Alkaloids from the Arctic Bacterium, Pseudomonas aeruginosa (북극해 박테리아, Pseudomonas aeruginosa에서 분리된 퀴놀론 알칼로이드)

  • Youn, Ui Joung;Han, Se Jong;Kim, Il Chan;Yim, Jung Han
    • Korean Journal of Pharmacognosy
    • /
    • v.49 no.2
    • /
    • pp.108-112
    • /
    • 2018
  • Four quinolone alkaloids, 2-heptyl-4-quinolone (1), 2-nonyl-4-quinolone (2), 2-undecyl-4-quinolone (3), and 2-undecen-1'-yl-4-quinolone (4), together with two nitrogen derived benzoic acid derivatives, N-acetylanthranilic acid (5) and o-acetamidobenzamide (6) have been isolated from the Arctic bacterial strain, Pseudomonas aeruginosa. The structures of the compounds were determined by 1D and 2D NMR, and MS experiments, as well as by comparison of their data with published values. To the best of our knowledge, compounds 3-6 were isolated for the first time from P. aeruginosa.

Estimation of extreme wind pressure coefficient in a zone by multivariate extreme value theory

  • Yang, Qingshan;Li, Danyu;Hui, Yi;Law, Siu-Seong
    • Wind and Structures
    • /
    • v.31 no.3
    • /
    • pp.197-207
    • /
    • 2020
  • Knowledge on the design value of extreme wind pressure coefficients (EWPC) of a specific zone of buildings is essential for the wind-resistant capacity of claddings. This paper presents a method to estimate the representative EWPC introducing the multivariate extreme value model. The spatial correlations of the extreme wind pressures at different locations can be consider through the multivariate extreme value. The moving average method is also adopted in this method, so that the measured point pressure can be converted to wind pressure of an area. The proposed method is applied to wind tunnel test results of a large flat roof building. Comparison with existing methods shows that it can give a good estimation for all target zones with different sizes.

A Study on the Modification and Development of Curriculum for the Department of Food and Nutrition in Junior College (전문대학 식품영양과 교육과정의 수정 개발에 관한 연구)

  • Nam, Gung-Seok;So, Myeong-Hwan;Yun, Seong-Sik
    • The Korean Journal of Food And Nutrition
    • /
    • v.2 no.1
    • /
    • pp.45-60
    • /
    • 1989
  • According as the economic growth and the development of highly industrialized society have improved the nation's standard of living, a great change in recognition of public health has occurred and also brought about a concomitant change in the roles and responsibilities of nutritionists. Consequently, the curriculum of Junior Colleges is required to be revised so as to provide substantial education through which the acquisition of necessary professional knowledge and technique as intermediate technicians and the efficient training can be achieved. On the basis of the survey and analysis of the current curriculum and of the functional structures of nutritionists, this study made an attempt to frame a model curriculum that may provide effective education and training and help to establish a desirable curriculum of Junior Colleges.

  • PDF

Recent Researches for Diatom as Inorganic and Bioenvironmental Materials (무기소재 및 생물환경 소재로서의 규조류 활용 연구 동향)

  • Jang, Eui Kyoung;Shin, Hyun Kyeong;Pack, Seung Pil
    • KSBB Journal
    • /
    • v.29 no.1
    • /
    • pp.9-21
    • /
    • 2014
  • One of the most abundant microalgaes, diatom is characterized by its unique cell wall structures composed of nano-patterned silica. Due to its highly ordered porosity, these silica frustules, which are found as sediments called diatomite, were used as a cheap adsorption material for water purification. Recently, new emerging nanotechnology compels many researchers to have interest in such diatom's unique properties (eg, nano-scale mesoporosity, photo luminescence, light transparency, etc.) as biogenic inorganic materials as well as the biomass resource (conventional usage of microalgae). In this review, we will focus on the current knowledge about the diatoms research and the possibility of its applications.

Entropy-based optimal sensor networks for structural health monitoring of a cable-stayed bridge

  • Azarbayejani, M.;El-Osery, A.I.;Taha, M.M. Reda
    • Smart Structures and Systems
    • /
    • v.5 no.4
    • /
    • pp.369-379
    • /
    • 2009
  • The sudden collapse of Interstate 35 Bridge in Minneapolis gave a wake-up call to US municipalities to re-evaluate aging bridges. In this situation, structural health monitoring (SHM) technology can provide the essential help needed for monitoring and maintaining the nation's infrastructure. Monitoring long span bridges such as cable-stayed bridges effectively requires the use of a large number of sensors. In this article, we introduce a probabilistic approach to identify optimal locations of sensors to enhance damage detection. Probability distribution functions are established using an artificial neural network trained using a priori knowledge of damage locations. The optimal number of sensors is identified using multi-objective optimization that simultaneously considers information entropy and sensor cost-objective functions. Luling Bridge, a cable-stayed bridge over the Mississippi River, is selected as a case study to demonstrate the efficiency of the proposed approach.

Developing An Expert System for The Selection of Foundation Types and Methods (기초 형식 및 공법 선정을 위한 전문가 시스템 개발)

  • 정영식;이종석;김태헌;홍운철
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1998.10a
    • /
    • pp.381-388
    • /
    • 1998
  • This paper describes the development of an expert system designed to help engineers select proper foundation types and construction methods for structures under various subsoil conditions. The system includes geographical and geological data in certain areas of Ulsan and a knowledge base for the selection of foundation types. Geological data, such as boring logs, in the areas were collected and arranged to form the subsoil database in the areas concerned Test borings at 30 holes were carried out for reference and confirmation purposes. The use of this system is twofold. It provides the users with a quick view on the geological situations of the areas concerned, and suggests proper foundation types for the specific spot together with some explanations on the selected foundation types and methods.

  • PDF

Haut - A 21-storey Tall Timber Residential Building

  • Verhaegh, Rob;Vola, Mathew;de Jong, Jorn
    • International Journal of High-Rise Buildings
    • /
    • v.9 no.3
    • /
    • pp.213-220
    • /
    • 2020
  • This paper reflects on the structural design of Haut; a 21-storey high-end residential development in Amsterdam, the Netherlands. Construction started in 2019 and is in progress at the time of writing. Upon completion in 2021, Haut will be the first residential building in the Netherlands to achieve a 'BREEAM-outstanding' classification. The building will reach a height of 73 m, making it the highest timber structure in the Netherlands. It contains some 14.500 ㎡ of predominantly residential functions. It features a hybrid concrete-timber stability system and concrete-timber floor panels. This paper describes the concepts behind the structural design for Haut and will touch upon the main challenges that have arisen from the specific combination of characteristics of the project. The paper describes the design of the stability system and -floor system, the analysis of differential movements between concrete and timber structures and wind vibrations. The paper aims to show how the design team has met these specific challenges by implementing a holistic design approach and integrating market knowledge at an early stage of the design.