检索结果-南通市图书馆

From 'glass basins' to 'glass barriers'

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 95-96页

作者： Yuliang Jin institute of Theoretical Physics Chinese Academy of Sciences School of Physical sciences University of Chinese Academy of Sciences Center for Theoretical Interdisciplinary sciences Wenzhou InstituteUniversity of Chinese Academy of Sciences

If a supercooled liquid is cooled rapidly to avoid crystallization, a glass is *** this procedure, the viscosity can increase by more than 10 orders of magnitude over a small temperature range near the glass transitio... 详细信息

关键词： LIQUIDS

How to build a habitable planet:an interview with Charles H. Langmuir

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 76-80页

作者： Yi-Gang Xu the Guangzhou institute of Geochemistry Chinese Academy of Sciences

Earth is the only known habitable planet in the solar system. Understanding how Earth developed its unique habitability has been the frontier of Earth sciences and has become one of the main themes of current deep-space explorations. What are the decisive factors that led to a habitable planet? What is the role of solid Earth processes in the origin of life and in modulating the surface environment? Are Earth’s habitability studies relevant to current challenges that human beings face? These questions have attracted the interest of both scientists and the public alike.

关键词： Earth (planet)

Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong Yan Xiliang Li Ke Jin institute of Grassland Research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P < 0.001), which were driven by dominance effects. The community had lower overall biomass when forbs were sown first, whereas the species grown later had fewer costs with an increased overall net benefit for the resulting *** Our results emphasize that root interactions and asymmetric competition are vital determinants of order-specific priority effects in community assemblies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

Water quality and habitat drive phytoplankton taxonomic and functional group patterns in the Yangtze River

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2024年第1期13卷 144-158页

作者： Wenqi Gao Fangyuan Xiong Ying Lu Wei Xin Haihua Wang Gangpeng Feng Chiping Kong Lei Fang Xiaoping Gao Yushun Chen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of sciences Jiangxi institute for Fisheries sciences Poyang Lake Fisheries Research Centre of Jiangxi Province East China Sea Fisheries Research institute Chinese Academy of Fishery Sciences Jiujiang institute of Agricultural sciences

Background Although phytoplankton are important primary producers in food webs, they are relatively less studied in large rivers compared to other types of systems. To fill this research gap, we studied phytoplankton taxonomic and functional composition and their relationships with water quality, habitat, climate, and land use across 30 river sections in the middle and lower reaches of the Yangtze River during 2017–*** Major observed phytoplankton groups were cyanobacteria, bacillariophyta, and chlorophyta. Phytoplankton total abundance, total biomass, and species richness significantly decreased in the dry season compared to the wet season, with the species and functional composition differing significantly between seasons. Phytoplankton species differences between seasons were mainly contributed by Oscillatoria sp., Pseudanabaena sp., and Melosira granulata. The dfferences in phytoplankton functional groups between seasons were mainly contributed by P（including Closterium sp., Melosira sp.）, Lo（including Merismopedia sp., Peridinium sp., Ceratium sp., and Gymnodinium sp.）, and J（including Pediastrum sp., Tetraedron sp., Crucigenia sp., Scenedesmus sp., and Coelastrum sp.）. The variance partitioning showed that water quality（NO3-N, total suspended solids, turbidity） and habitat（water flow, river bank and river channel conditions） were critical factors in shaping phytoplankton patterns, followed by climate and land *** Results indicated that there was significant seasonal variation of phytoplankton in the Yangtze River, with water quality and habitat primarily driving phytoplankton patterns. Our study contributes to the understanding of natural and anthropogenic factors that drive seasonal successional processes of phytoplankton in the Yangtze River. These findings have important implications for environmental management as well as towards the ecological restoration of large rivers.

关键词： Yangtze River Phytoplankton Functional group Water quality Physical habitat

A novel pathogen Fusarium cuneirostrum causing common bean(Phaseolus vulgaris)root rot in China

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2024年第1期23卷 166-176页

作者： Dong Deng Wenqi Wu Canxing Duan Suli Sun Zhendong Zhu institute of Crop sciences Chinese Academy of Agricultural SciencesBeijing 100081China

Several fungal pathogens cause root rot of common bean,among which Fusarium *** the most common pathogens causing Fusarium root rot(FRR)*** has been becoming an increasingly severe disease of common bean in China,but the species of Fusarium *** remained ***,this study was performed to identify the pathogen causing common bean root rot in Liangcheng County,Inner Mongolia,*** Fusarium-like isolates were obtained after pathogen isolation and *** pathogenicity test indicated that eight isolates caused severe disease symptoms on common bean,while 11 other isolates were not *** eight pathogenic isolates,FCL1–FCL8,were identified as Fusarium cuneirostrum by morphological characterization and phylogenetic analysis using partial sequences of EF-1α,ITS,28S,and IGS *** range test showed that the representative *** isolate FCL3 was also pathogenic to mung bean,while not pathogenic to adzuki bean,chickpea,cowpea,faba bean,pea,and ***,50 common bean and 50 mung bean cultivars were screened for resistance to FRR,and seven highly resistant or resistant cultivars of common bean were identified,while no resistant cultivars of mung bean were *** study revealed that *** was one of common bean FRR pathogens in Inner Mongolia and it could induce mung bean root rot as *** our knowledge,this is the first report of *** causing FRR of common bean in China.

关键词： Fusarium cuneirostrum fusarium root rot pathogenicity molecular phylogenetic analysis Phaseolus vulgaris

Change in observed long-term greening across Switzerlandevidence from a three decades NDVI time-series and its relationship with climate and land cover factors

在线全文

学校读者我要写书评

暂无评论

Big Earth Data 2024年第1期8卷 1-32页

作者： Claire Obuchowicz Charlotte Poussin Gregory Giuliani institute for Environmental sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland institute for Environmental sciences University of GenevaGenevaSwitzerland

Environmental changes are significantly modifying terrestrial vegetation dynamics,with serious consequences on Earth system functioning and provision of ecosystem *** conditions are an essential element underpinning global sustainability frameworks,such as the Sustainable Development Goals(SDGs),requiring effective solutions to assess the impacts of changing land conditions induced by various driving *** the global scale,long-term increase of vegetation greening has been widely reported notably in seasonally snow-covered ecosystems as a response to warming ***,greening trends at the national scale have received less attention,although countries like Switzerland are prone to important changing climate ***,we used a 35-year satellite-derived annual and seasonal time-series of Normalized Difference Vegetation Index(NDVI)to assess vegetation greenness evolution at different spatial and temporal scales across Switzerland and related them to temperature,precipitation,and land cover to investigate possible responses of changing climatic *** indicate that there is a statistically significant greening trend at the national scale with an NDVI mean increasing slope of 0.6%/year for the 61%significant pixels across *** particular,the seasonal mean NDVI shows an important break for winter,autumn and spring seasons starting from 2010,potentially indicating a critical point of changing land *** biogeographical scale,we observed an apparent clustering(Jura-Plateau;Northern-Southern Alps;Eastern-Western Alps)related to landscape characteristics,while forested land cover classes are more responsive to NDVI ***,the NDVI values are mostly a function of temperature at elevations below the tree line rather than *** findings suggest that multi-annual and seasonal NDVI can be a valuable indicator to monitor vegetation conditions at different scales and can provide complementary observati

关键词： Landsat climate land cover NDVI anomaly

Reconstruction algorithm for cross-waveband optical computing imaging

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第10期33卷 233-239页

作者： Jin-Tao Xie Shu-Hang Bie Ming-Fei Li Yuan-Jin Yu Yi-Fei Li Jin-Guang Wang Bao-Gang Quan Ling-An Wu institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China School of Automation Beijing Institute of TechnologyBeijing 100081China

In a single-pixel fast imaging setup,the data collected by the single-pixel detector needs to be processed by a computer,but the speed of the latter will affect the image reconstruction *** we propose two kinds of setups which are able to transform non-visible into visible light imaging,wherein their computing process is replaced by a camera integration *** image captured by the camera has a low contrast,so here we present an algorithm that can realize a high quality image in near-infrared to visible cross-waveband *** scheme is verified both by simulation and in actual *** setups demonstrate the great potential for single-pixel imaging and high-speed cross-waveband imaging for future practical applications.

关键词： optical computing imaging single-pixel imaging

A four-band index for both liquid and solid water and its applications in the Aral Sea Basin

在线全文

学校读者我要写书评

暂无评论

Science China Earth sciences 2024年第3期67卷 769-788页

作者： Bing YUE Xi CHEN Saibo LI Zhengping DU John WILSON Junhui YANG Yimen JIAO Shuangyan HUANG Chenghu ZHOU Xinjiang institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China institute of Geographical sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Spatial sciences institute University of Southern CaliforniaLos AngelesCA 90089-0374USA

Various investigations have been conducted to analyze the water-coverage area of the Aral Sea and the Aral Sea Basin(ASB). However, the investigations incorporated considerable uncertainty and the used water indices had misclassification problem, which made different research groups present different results. Thus we first ascertain the boundaries of the ASB, the Syr and Amu river basins as well as their upper, middle and lower reaches. Then a four-band index for both liquid and solid water(ILSW) is proposed to address the misclassification problems of the classic water indices. ILSW is calculated by using the reflectance values of the green, red, near infrared, and thermal infrared bands, which combines the normalized difference water index(NDWI) and land surface temperature(LST) together. Validation results show that the ILSW water index has the highest accuracy by far in the Aral Sea Basin. Our results indicate that annual average decline of the water-coverage area was 963 km^(2) in the southern Aral Sea, whereas the northern Aral Sea has experienced little change. In the meanwhile, permanent ice and snow in upper reach of ASB has retreated considerably. Annual retreating rates of the permanent ice and snow were respectively 6233and 3841 km^(2) in upper reaches of Amu river basin(UARB) and Syr river basin(USRB). One of major reasons is that climate has become warmer in ASB. The climate change has caused serious water deficit problem. The water deficit had an increasing trend since the 1990s and its increasing rates was 3.778 billion m^(3) yearly on average. The total water deficit was 76.967 billion m^(3) on average in the whole area of ASB in the 2010s. However, up reaches of Syr river basin(USRB), a component area of ASB, had water surplus of 25.461 billion m^(3). These conclusions are useful for setting out a sustainable development strategy in ASB.

关键词： Aral Sea Basin Syr river basin Amu river basin Water indices Water-coverage area Water deficit Climate change

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya V.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova Elena N.Danilovtseva Vadim V.Annenkov institute of Macromolecular Compounds of the Russian Academy of sciences Saint Petersburg199004Russia Limnological institute of Siberian Branch of the Russian Academy of sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization