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Review of Research Methods on Biodiversity of Arbuscular Mycorrhizal Fungi 被引量:1
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作者 李凌飞 付晓萍 董文明 《Agricultural Science & Technology》 CAS 2012年第3期600-604,共5页
Arbuscular mycorrhizal fungi (AMF) are essential functional microbiology in natural ecosystems. It is very important to research community composition and di- versity of AMF for achieving sustainable development of ... Arbuscular mycorrhizal fungi (AMF) are essential functional microbiology in natural ecosystems. It is very important to research community composition and di- versity of AMF for achieving sustainable development of ecosystems. The paper described several methods of researching the diversity of AMF, especially for molecular techniques, reviewed the application status of these methods in AMF research, and pointed out that the effective combination of morphological and molecular methods could better reveal the biodiversity and ecological functions of AMF in natural ecosystems. 展开更多
关键词 Arbuscular Mycorrhizal Fungi (AMF) BIODIVERSITY morphological method Phospholipid fatty acid (PLFA) method Molecular biotechnology
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Transformation Pathway of Carbonate Pedofeatures Based on Their Micromorhology and Carbon Isotope Data in the Northern Caucasus Region,Russia
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作者 Khokhlova O.S. Kouznetsova A.M. Khokhlov A. A. 《Journal of Mountain Science》 SCIE CSCD 2009年第2期139-146,共8页
Carbonate pedofeatures (CPs) in a chronosequence of paleosols buried under kurgans in the Northern Caucasus region of Russia in a period from the end of the 4th to the middle of the 5th centuries AD (It seams that the... Carbonate pedofeatures (CPs) in a chronosequence of paleosols buried under kurgans in the Northern Caucasus region of Russia in a period from the end of the 4th to the middle of the 5th centuries AD (It seams that there is no time left) were studied by using a set of morphological and isotopic methods. The CPs in chernozem-type soils of Russia are usually represented by crystallomorphic calcite whereas the non-segregated carbonates occurred at the same horizons-by collomorphic one. Those two morphotypes of calcite have the differences in elemental composition and isotopic composition of carbon and, hence, should have different origins-from true and colloidal solutions, respectively. The same differences including radiocarbon age have been revealed for pseudomycelium of the ABca horizon of the youngest paleosols as compared with the same CPs of other paleosols in the chronosequence studied. Our assumption is that it was succeeded in finding that the pseudomycelium right away after its precipitation from a colloidal solution migrated from the lower soil horizons to the surface horizons during the periods of climatic aridization. After a short time interval (not more than 25-50 years) collomorphic calcite in the pseudomicelium of the yongest paleosols mentioned above will likely become by "usual" acicular calcite. 展开更多
关键词 Carbonate pedofeature CHERNOZEMS kurgans holocene paleosol set of morphological andisotopic method
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Runout of submarine landslide simulated with material point method 被引量:6
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作者 Youkou Dong Dong Wang Mark F.Randolph 《Journal of Hydrodynamics》 SCIE EI CSCD 2017年第3期438-444,共7页
Most of the present knowledge on submarine landslides relies upon back-analysis of post-failure deposits identified using geophysical techniques.In this paper,the runout of slides on rigid bases is explored using the ... Most of the present knowledge on submarine landslides relies upon back-analysis of post-failure deposits identified using geophysical techniques.In this paper,the runout of slides on rigid bases is explored using the material point method(MPM)with focus on the geotechnical aspects of the morphologies.In MPM,the sliding material and bases are discretised into a number of Lagrangian particles,and a background Eulerian mesh is employed to update the state of the particles.The morphologies of the slide can be reproduced by tracking the Lagrangian particles in the dynamic processes.A real case history of a submarine slide is back-analyzed with the MPM and also a depth-averaged method.Runout of the slides from steep slopes to moderate bases are reproduced.Then different combinations of soil and basal parameters are assumed to trigger runout mechanisms of elongation,block sliding and spreading.The runout distances predicted by the MPM match well with those from large deformation finite element analysis for the elongation and block sliding patterns.Horst and grabens are shaped in a spreading pattern.However,the current MPM simulations for materials with high sensitivities are relatively mesh sensitive. 展开更多
关键词 Submarine landslide runout morphology material point method large deformation
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Empty glass bottle inspection method based on fuzzy support vector machine neural network and machine vision
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作者 Huanjun LIU 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2010年第4期430-440,共11页
This paper develops a computerized empty glass bottle inspection method.Wavelet transform and morphologic methods were employed to extract features of the bottle body and the finish from images.Fuzzy support vector ma... This paper develops a computerized empty glass bottle inspection method.Wavelet transform and morphologic methods were employed to extract features of the bottle body and the finish from images.Fuzzy support vector machine neural network was adopted as classifiers for the extracted features.Experimental results indicated that the accuracy rate can reach up to 97%by using the method developed to inspect empty glass bottles. 展开更多
关键词 machine vision support vector machine(SVM) neural network(NN) morphologic method wavelet transform
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Improving outdoor air quality based on building morphology:Numerical investigation 被引量:1
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作者 Asmaa Mohammed Hassan Ashraf Abdel Fatah El Mokadem 《Frontiers of Architectural Research》 CSCD 2020年第2期319-334,共16页
Due to rapid urbanization around the world,high concentrations of vehicular pollutants have deteriorated the outdoor air quality,which can affect the physical and psychological well-being of humans.Numerous strategies... Due to rapid urbanization around the world,high concentrations of vehicular pollutants have deteriorated the outdoor air quality,which can affect the physical and psychological well-being of humans.Numerous strategies have been proposed to overcome these harmful impacts by improving the dispersion of air pollutants.Consequently,a question arises regarding the potential effects of building morphology on the dispersion of pollutants.Subsequently,transient three-dimensional Computational Fluid Dynamics(CFD)simulations are performed to examine the effect of building morphology on PM10 dispersion.Eleven cases with various prototypes and morphological methods are compared with a simple building form to identify the patterns of PM10 dispersion within a given time sequence under a prevailing inflow condition.The results indicate that the different designs of building morphology with varying Relative compactness(RC)indicator highlight the importance of considering morphological factors to improve outdoor air quality.In addition,the proposed prototypes can reduce PM10 concentrations by approximately 30%e90%at specific points in the studied time sequence.In particular,the vertical,horizontal,and grid folded prototypes can be considered more effective as an approximate decrease between 70%and 90%in PM10 concentrations is observed,which reflects the influence of building morphology on improving outdoor air quality. 展开更多
关键词 Building morphology morphological methods Outdoor air quality PM10 dispersion CFD simulation
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Formation of the modern scenic city of Hangzhou:towards conservation integrated urban planning,1950s–1990s
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作者 Shulan Fu Panpan Jin 《Built Heritage》 CSCD 2020年第3期18-31,共14页
From the 1950s to the 1990s,China underwent a significant transformation of its political system and economy,from socialism to rapid development after the reform and opening up.In the 1980s and 1990s,to meet the deman... From the 1950s to the 1990s,China underwent a significant transformation of its political system and economy,from socialism to rapid development after the reform and opening up.In the 1980s and 1990s,to meet the demand for housing and urban modernization under the rapid growth of cities,almost all Chinese cities underwent large-scale urban construction,transformation and expansion.With this background of rapid advancement,many cities have lost their traditional urban features and characteristics.However,it was during this period that Hangzhou not only restored the historical scenery of West Lake through multiple projects but also explored overall planning of the city and introduced conservation ideas,making West Lake,which was originally located outside the city,part of the city.This period also shaped the contemporary urban characteristics of Hangzhou with traditional landscape features.To explore Hangzhou’s positive experience and determine the critical junctures and influencing factors,this study observed the entire historical process using morphological methods.Based on a summary of the characteristics of each development stage,this study further focuses on the key issue of how conservation ideas are gradually introduced into urban planning and affect the development process. 展开更多
关键词 Hangzhou West Lake 1950s–1990s morphological method CONSERVATION urban planning scenic city
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Characteristics, Multi-Phase Evolution and Genesis of Weathering Pits in Qing Mountain, Inner Mongolia, China 被引量:1
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作者 田飞 田明中 刘瑾 《Journal of Earth Science》 SCIE CAS CSCD 2013年第3期457-470,共14页
A total of 80 weathering pits (gnammas), located on granite surfaces of Qing Mountain (青山), Hexigten (克什克腾) Global Geopark, Inner Mongolia, were identified and measured in terms of dimensional and orientat... A total of 80 weathering pits (gnammas), located on granite surfaces of Qing Mountain (青山), Hexigten (克什克腾) Global Geopark, Inner Mongolia, were identified and measured in terms of dimensional and orientational features. This article attempts to extract characteristics of the weathering pits by descriptive statistics and orientation rose diagrams, investigate the multi-phase evolution by the modified gnamma morphological analysis (GMA) method, and shed new light on the possible genesis and the influencing factors. Following the modified GMA method, weathering pits in Qing Mountain have been divided into six groups and compared with analogous sites to deduce their approximate age, which might be no older than 30 ka B.P., and explore the possibility that the multi-phase evolution of weathering pits may arise from responses to climate change. In consequence, we suggest that the combination of weathering, especially salt weathering, and wind erosion, both of which are closely related to climatic variation, take the main responsibility for the formation and development of weathering pits in Qing Mountain. 展开更多
关键词 weathering pit modified gnamma morphological analysis method multi-phase evolu- tion GENESIS Qing Mountain Inner Mongolia.
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