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β-多样性的研究:应用多元回归和典范分析研究生态方差的分解 被引量:23
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作者 Pierre Legendre 《植物生态学报》 CAS CSCD 北大核心 2007年第5期976-981,共6页
β-多样性刻画了地理区域中不同地点物种组成的变化,是理解生态系统功能、生物多样性保护和生态系统管理的一个重要概念。该文介绍了如何从群落组成,相关环境和空间数据角度去分析β-多样性。β-多样性可以通过计算每个地点的多样性指数... β-多样性刻画了地理区域中不同地点物种组成的变化,是理解生态系统功能、生物多样性保护和生态系统管理的一个重要概念。该文介绍了如何从群落组成,相关环境和空间数据角度去分析β-多样性。β-多样性可以通过计算每个地点的多样性指数,进而对可能解释点之间差异的因子所作的假设进行检验来研究。也可以将涵盖所有点的群落组成数据表看作是一系列环境和空间变量的函数,进行直接分析。这种分析应用统计方法将多样性指数或群落组成数据表的方差进行关于环境和空间变量的分解。该文对方差分解进行阐述。方差分解是利用环境和空间变量来解释β-多样性的一种方法。β-多样性是生态学家用来比较不同地点或同一地点不同生态群落的一种手段。方差分解就是将群落组成数据表的总方差无偏分解成由各个解释变量所决定的子方差。调整的决定系数提供了针对多元回归和典范冗余分析的无偏估计。方差分解后,可以对感兴趣的方差解释部分进行显著性检验,同时绘出基于这部分方差解释的预测图。 展开更多
关键词 调整的决定系数 β-多样性 生物多样性 典范冗余分析 群落组成 方差分解
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The IKK-related kinases: from innate immunity to oncogenesis 被引量:16
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作者 Jean-Francois Clément 《Cell Research》 SCIE CAS CSCD 2008年第9期889-899,共11页
Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the acti... Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the activity of interferon regulatory factor (IRF)-3/IRF-7 and NF-κB transcription factors. More recently, additional essential components of the signaling pathways that activate these IKK homologues have been discovered. These include the RNA helicases RIGi and MDA5, and the downstream mitochondrial effector known as CARDIF/MAVS/VISA/IPS-1. In addition to their essential functions in controlling the innate immune response, recent studies have highlighted a role of these kinases in cell proliferation and oncogenesis. The canonical IKKs are well recognized to be a bridge linking chronic inflammation to cancer. New findings now suggest that the IKK-related kinases TBK1 and IKKi also participate in signaling pathways that impact on cell transformation and tumor progression. This review will therefore summarize and discuss the role of TBK1 and IKKi in cellular transformation and oncogenesis by focusing on their regulation and substrate specificity. 展开更多
关键词 cancer IKKi TBK 1 CYTOKINES NF-κB interferon regulatory factor INFLAMMATION
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Biochar amendments increase soil organic carbon storage and decrease global warming potentials of soil CH4 and N2O under N addition in a subtropical Moso bamboo plantation 被引量:4
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作者 Quan Li Kunkai Cui +5 位作者 Jianhua Lv Junbo Zhang Changhui Peng Yongfu Li Zhikang Gu Xinzhang Song 《Forest Ecosystems》 SCIE CSCD 2022年第4期567-576,共10页
Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate... Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate the promoting effects of N input on GHG emissions in forest soils. Here, we quantify the separate and combined effects of biochar amendment(0, 20, and 40 t·ha) and N addition(0, 30, 60, and 90 kg N·ha·yr) on soil GHG fluxes in a long-term field experiment at a Moso bamboo(Phyllostachys edulis) plantation.Results: Low and moderate N inputs(≤60 kg N·ha·yr) significantly increase mean annual soil carbon dioxide(CO) and nitrous oxide(NO) emissions by 17.0%–25.4% and 29.8%–31.2%, respectively, while decreasing methane(CH) uptake by 12.4%–15.9%, leading to increases in the global warming potential(GWP) of soil CHand NO fluxes by 32.4%–44.0%. Moreover, N addition reduces soil organic carbon(C;SOC) storage by 0.2%–6.5%. Compared to the control treatment, biochar amendment increases mean annual soil CO2emissions, CHuptake, and SOC storage by 18.4%–25.4%, 7.6%–15.8%, and 7.1%–13.4%, respectively, while decreasing NO emissions by 17.6%–19.2%, leading to a GWP decrease of 18.4%–21.4%. Biochar amendments significantly enhance the promoting effects of N addition on soil COemissions, while substantially offsetting the promotion of N2O emissions, inhibition of CHuptake, and decreased SOC storage, resulting in a GWP decrease of 9.1%–30.3%.Additionally, soil COand CHfluxes are significantly and positively correlated with soil microbial biomass C(MBC) and pH. Meanwhile, NO emissions have a significant and positive correlation with soil MBC and a negative correlation with pH.Conclusions: Biochar amendment can increase SOC storage and offset the enhanced GWP mediated by elevated N deposition and is, thus, a potential strategy for increasing soil C sinks and decreasing GWPs of soil CHand NO under increasing atmospheric N deposition in Moso bamboo plantations. 展开更多
关键词 Biochar application Nitrogen addition Greenhouse gas Global warming potential PLANTATION
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旅游规划的战略工具:全球可持续旅游目的地标准 被引量:3
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作者 Franois Bédard 黄潇婷 《旅游学刊》 CSSCI 2013年第9期6-8,共3页
可持续旅游正在兴起,旅游者需求不断增长,旅游经营者正在开发新的绿色旅游产品,各国政府以及国际机构正在制定新政策,以鼓励可持续旅游的发展。然而,“可持续旅游”的真正含义是什么?从获得旅游者信任、促进旅游业繁荣、带动社区... 可持续旅游正在兴起,旅游者需求不断增长,旅游经营者正在开发新的绿色旅游产品,各国政府以及国际机构正在制定新政策,以鼓励可持续旅游的发展。然而,“可持续旅游”的真正含义是什么?从获得旅游者信任、促进旅游业繁荣、带动社区发展到避免“可持续旅游”变成被到处乱贴的标签,我们该怎样寻求一种可信而正确的界定方法与评价依据呢?本文基于全球可持续旅游目的地标准工作组近年来的研究结果,尤其是目的地课题组的研究,探索可持续旅游视角下的旅游规划概念和方法。 展开更多
关键词 旅游目的地 旅游规划 标准 可持续旅游 工具 旅游经营者 旅游产品 国际机构
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Management scheme influence and nitrogen addition effects on soil CO_(2),CH_(4),and N_(2)O fluxes in a Moso bamboo plantation 被引量:3
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作者 Junbo Zhang Quan Li +5 位作者 Jianhua Lv Changhui Peng Zhikang Gu Lianghua Qi Xuzhong Song Xinzhang Song 《Forest Ecosystems》 SCIE CSCD 2021年第1期69-80,共12页
Background:It is still not clear whether the effects of N deposition on soil greenhouse gas(GHG)emissions are influenced by plantation management schemes.A field experiment was conducted to investigate the effects of ... Background:It is still not clear whether the effects of N deposition on soil greenhouse gas(GHG)emissions are influenced by plantation management schemes.A field experiment was conducted to investigate the effects of conventional management(CM)versus intensive management(IM),in combination with simulated N deposition levels of control(ambient N deposition),30 kg N·ha^(−1)·year^(−1)(N30,ambient+30 kg N·ha^(−1)·year^(−1)),60 kg N·ha^(−1)·year^(−1)(N60,ambient+60 kg N·ha^(−1)·year^(−1)),or 90 kg N·ha^(−1)·year^(−1)(N90,ambient+90 kg N·ha^(−1)·year^(−1))on soil CO_(2),CH_(4),and N_(2)O fluxes.For this,24 plots were set up in a Moso bamboo(Phyllostachys edulis)plantation from January 2013 to December 2015.Gas samples were collected monthly from January 2015 to December 2015.Results:Compared with CM,IM significantly increased soil CO_(2) emissions and their temperature sensitivity(Q_(10))but had no significant effects on soil CH_(4) uptake or N_(2)O emissions.In the CM plots,N30 and N60 significantly increased soil CO_(2) emissions,while N60 and N90 significantly increased soil N_(2)O emissions.In the IM plots,N30 and N60 significantly increased soil CO_(2) and N_(2)O emissions,while N60 and N90 significantly decreased soil CH_(4) uptake.Overall,in both CM and IM plots,N30 and N60 significantly increased global warming potentials,whereas N90 did not significantly affect global warming potential.However,N addition significantly decreased the Q_(10) value of soil CO_(2) emissions under IM but not under CM.Soil microbial biomass carbon was significantly and positively correlated with soil CO_(2) and N_(2)O emissions but significantly and negatively correlated with soil CH_(4) uptake.Conclusion:Our results indicate that management scheme effects should be considered when assessing the effect of atmospheric N deposition on GHG emissions in bamboo plantations. 展开更多
关键词 Greenhouse gases Management practices Nitrogen addition Phyllostachys edulis Q_(10)
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The functional complex network approach to foster forest resilience to global changes 被引量:2
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作者 Christian Messier Jürgen Bauhus +7 位作者 Frederik Doyon Fanny Maure Rita Sousa-Silva Philippe Nolet Marco Mina Núria Aquilué Marie-Josée Fortin Klaus Puettmann 《Forest Ecosystems》 SCIE CSCD 2019年第3期194-209,共16页
Human impacts on Earth's ecosystems have greatly intensified in the last decades. This is reflected in unexpected disturbance events, as well as new and increasing socio-economic demands, all of which are affectin... Human impacts on Earth's ecosystems have greatly intensified in the last decades. This is reflected in unexpected disturbance events, as well as new and increasing socio-economic demands, all of which are affecting the resilience of forest ecosystems worldwide and the provision of important ecosystem services. This Anthropocene era is forcing us to reconsider past and current forest management and silvicultural practices, and search for new ones that are more flexible and better at dealing with the increasing uncertainty brought about by these accelerating and cumulative global changes. Here, we briefly review the focus and limitations of past and current forest management and silvicultural practices mainly as developed in Europe and North America. We then discuss some recent promising concepts, such as managing forests as complex adaptive systems, and approaches based on resilience, functional diversity, assisted migration and multi-species plantations, to propose a novel approach to integrate the functionality of species-traits into a functional complex network approach as a flexible and multi-scale way to manage forests for the Anthropocene. This approach takes into consideration the high level of uncertainty associated with future environmental and societal changes. It relies on the quantification and dynamic monitoring of functional diversity and complex network indices to manage forests as a functional complex network. Using this novel approach, the most efficient forest management and silvicultural practices can be determined, as well as where, at what scale, and at what intensity landscape-scale resistance, resilience and adaptive capacity of forests to global changes can be improved. 展开更多
关键词 FOREST management North AMERICA ECOSYSTEM services
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Importance of initial buoyancy field on evolution of mantle thermal structure:Implications of surface boundary conditions
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作者 Petar Gliovi Alessandro M.Forte 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第1期3-22,共20页
Although there has been significant progress in the seismic imaging of mantle heterogeneity, the outstanding issue that remains to be resolved is the unknown distribution of mantle temperature anomalies in the distant... Although there has been significant progress in the seismic imaging of mantle heterogeneity, the outstanding issue that remains to be resolved is the unknown distribution of mantle temperature anomalies in the distant geological past that give rise to the present-day anomalies inferred by global tomography models. To address this question, we present 3-D convection models in compressible and self-gravitating mantle initialised by different hypothetical temperature patterns. A notable feature of our forward convection modelling is the use of self-consistent coupling of the motion of surface tectonic plates to the underlying mantle flow, without imposing prescribed surface velocities (i.e., p/ate-like boundary condition). As an approximation for the surface mechanical conditions before plate tectonics began to operate we employ the no-slip (rigid) boundary condition. A rigid boundary condition dem- onstrates that the initial thermally-dominated structure is preserved, and its geographical location is fixed during the evolution of mantle flow. Considering the impact of different assumed surface boundary conditions (rigid and plate-like) on the evolution of thermal heterogeneity in the mantle we suggest that the intrinsic buoyancy of seven superplumes is most-likely resolved in the tomographic images of present-day mantle thermal structure. Our convection simulations with a plate-like boundary condition reveal that the evolution of an initial cold anomaly beneath the Java-lndonesian trench system yields a long-term, stable pattern of thermal heterogeneity in the lowermost mantle that resembles the present- day Large Low Shear Velocity Provinces (LLSVPs), especially below the Pacific. The evolution of sub- duction zones may be, however, influenced by the mantle-wide flow driven by deeply-rooted and long- lived superplumes since Archean times. These convection models also detect the intrinsic buoyancy of the Perm Anomaly that has been identified as a unique slow feature distinct from the two principal LLSVPs. We find there is no need for dense chemical 'piles' in the lower mantle to generate a stable distribution of temperature anomalies that are correlated to the LLSVPs and the Perm Anomaly. Our tomography-based convection simulations also demonstrate that intraplate volcanism in the south-east Pacific may be interpreted in terms of shallow small-scale convection triggered by a superplume beneath the East Pacific Rise. 展开更多
关键词 Dynamics: convection currents and mantleplumes HOTSPOTS Seismic tomography Planetary tectonics CMB topography Perm Anomaly
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Developing allometric equations to estimate forest biomass for tree species categories based on phylogenetic relationships
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作者 Mingxia Yang Xiaolu Zhou +7 位作者 Changhui Peng Tong Li Kexin Chen Zelin Liu Peng Li Cicheng Zhang Jiayi Tang Ziying Zou 《Forest Ecosystems》 SCIE CSCD 2023年第4期494-503,共10页
The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.Nat... The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.National Forest Inventories(NFI)are detailed assessments of forest resources at national and regional levels that provide valuable data for forest biomass estimation.However,the lack of biomass allometric equations for each tree species in the NFI currently hampers the estimation of national-scale forest biomass.The main objective of this study was to develop allometric biomass regression equations for each tree species in the NFI of China based on limited biomass observations.These equations optimally grouped NFI and biomass observation species according to their phylogenetic relationships.Significant phylogenetic signals demonstrated phylogenetic conservation of the crown-to-stem biomass ratio.Based on phylogenetic relationships,we grouped and matched NFI and biomass observation species into 22 categories.Allometric biomass regression models were developed for each of these 22 species categories,and the models performed successfully(R^(2)=0.97,root mean square error(RMSE)=12.9​t·ha^(–1),relative RMSE=11.5%).Furthermore,we found that phylogeny-based models performed more effectively than wood density-based models.The results suggest that grouping species based on their phylogenetic relationships is a reliable approach for the development and selection of accurate allometric equations. 展开更多
关键词 Allometric equation Forest biomass National Forest Inventory Species grouping Tree architecture Wood density
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Investigation of side chain liquid crystal polymers bearing cholesterol and bile acid derivatives
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作者 Stephen Freiberg Franεois Brisse C. Géraldine Bazuin 《合成化学》 CAS CSCD 2004年第z1期79-79,共1页
关键词 BILE acids LIQUID-CRYSTALLINE polymers X-ray
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A SIMPLE METHOD FOR THE INCORPORATION OF LOW MOLECULAR WEIGHT DYES IN ULTRATHIN FILMS
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作者 C. Geraldine Bazuin Carmen M. Tibirna 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第6期631-637,共7页
A simple method for the fabrication of ultrathin films containing low molecular weight dye material is introduced(post-adsorption technique). The chromophore used is 4-nitro-4'-decyloxy azobenzene quaternary ammon... A simple method for the fabrication of ultrathin films containing low molecular weight dye material is introduced(post-adsorption technique). The chromophore used is 4-nitro-4'-decyloxy azobenzene quaternary ammonium salt (azo-10Q).In classical layer-by-layer (LBL) procedures, where the substrate is dipped alternately into the chromophore solution and thecomplementary polyelectrolyte, the chromophore tends to desorb from the film during subsequent immersion in thepolyanion solution, and there is little or no indication of multilayer growth. The extent of desorption depends somewhat onthe selection of polyelectrolyte, the ionic strength and the pH of solution. An alternative approach is to first prepareconventional LBL films from a pair of oppositely charged polyelectrolytes, and then to soak this film into the chromophoresolution, where adsorption by penetration into the LBL film may take place. In preliminary results, a linear dependence ofUV absorbance on layer number of LBL film thus prepared was found, demonstrating the apparent effectiveness of the post-adsorption technique for the preparation of azo-10Q-containing ultrathin films. 展开更多
关键词 Ultrathin films Layer-by-layer Azo derivatives Polyelectrolytes Supramolecular complexes
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An analysis on Sino-Russian cooperation in the Arctic in the BRI era
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作者 Olga ALEXEEVA Frederic LASSERRE 《Advances in Polar Science》 2018年第4期269-282,共14页
Over the past decade Sino-Russian cooperation in the Arctic has emerged as one of the major topics of the Russia-China negotiations on how to expand their comprehensive strategic partnership and to bring it to a new l... Over the past decade Sino-Russian cooperation in the Arctic has emerged as one of the major topics of the Russia-China negotiations on how to expand their comprehensive strategic partnership and to bring it to a new level. China considers the Arctic region important for its economic interests and desires to be included in the development of the region and its economic potential. For Russia, the Arctic is a future strategic resource base that would replace the old depleting fields and assure Russia’s status as a major worldwide energy supplier. Despite many joint statements on deepening of the Sino-Russian cooperation in the development of the Arctic energy resources, the concrete results of these ambitious plans are few. Some joint projects were dropped, as China and Russia could not agree on the conditions of the deal, others are progressing very slowly and have an uncertain future. In 2017, China has expanded its "Belt and Road Initiative"(BRI) to the Arctic thus elevating the Sino-Russian cooperation in the Artcic to a higher level. How did the relationship between Russia and China evolve in the Arctic and how do Russia and China view and respond to the new Arctic dimension of the BRI? What factors limit the strategic rapprochement between China and Russia in the Arctic? 展开更多
关键词 ARCTIC China-Russia cooperation Belt and Road Initiative Yamal LNG Northern Sea Route
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Environment-Responsive Polymeric Hydrogels
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作者 M. Nichifor D. Avoce 《合成化学》 CAS CSCD 2004年第z1期78-78,共1页
关键词 LCST Environment-Responsive Polymeric Hydrogels
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Room Temperature Synthesis of Aminocaproic Acid-Capped Lead Sulphide Nanoparticles
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作者 Jayesh D.Patel Frej Mighri +1 位作者 Abdellah Ajji Said Elkoun 《Materials Sciences and Applications》 2012年第2期125-130,共6页
Aminocaproic acid (ACA) mixed methanolic lead acetate-thiourea (PbAc-TU) complex as precursor for fabrication of lead sulphide (PbS) nanoparticles (NPs) has been explained. The size, structure and morphology of as-pre... Aminocaproic acid (ACA) mixed methanolic lead acetate-thiourea (PbAc-TU) complex as precursor for fabrication of lead sulphide (PbS) nanoparticles (NPs) has been explained. The size, structure and morphology of as-prepared ACA-capped PbS NPs were systematically characterized by scanning electron microscopy (SEM), Transmission electron mi-croscopy (TEM), X-ray diffraction (XRD), Uv-vis spectroscopy and Brunauer-Emmett-Teller (BET) techniques. The obtained results show that the synthesized PbS NPs are nanocrystalline, size quantized and their agglomeration shows a mesoporous network of 8.7 nm in pore size. The binding nature of ACA molecules on PbS surface was studied by thermo gravimetric analysis (TGA), Fourier transform infrared (FTIR) and X-ray photoelectron (XPS) techniques. Results indicate that ACA acts as a soft template that restricts the growth of PbS NPs through its binding to Pb surface via nitrogen lone pair. 展开更多
关键词 Semiconductor NANOPARTICLES Lead Sulphide MESOPOROUS BET XPS FTIR
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Studying beta diversity: ecological variation partitioning by multiple regression and canonical analysis 被引量:20
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作者 Pierre Legendre 《Journal of Plant Ecology》 SCIE 2008年第1期3-8,共6页
Aims Beta diversity is the variation in species composition among sites in a geographic region.Beta diversity is a key concept for understanding the functioning of ecosystems,for the conservation of biodiversity and f... Aims Beta diversity is the variation in species composition among sites in a geographic region.Beta diversity is a key concept for understanding the functioning of ecosystems,for the conservation of biodiversity and for ecosystem management.The present report describes how to analyse beta diversity from community composition and associated environmental and spatial data tables.Methods Beta diversity can be studied by computing diversity indices for each site and testing hypotheses about the factors that may explain the variation among sites.Alternatively,one can carry out a direct analysis of the community composition data table over the study sites,as a function of sets of environmental and spatial variables.These analyses are carried out by the statistical method of partitioning the variation of the diversity indices or the community composition data table with respect to environmental and spatial variables.Variation partitioning is briefly described herein.Important findings Variation partitioning is a method of choice for the interpretation of beta diversity using tables of environmental and spatial variables.Beta diversity is an interesting‘currency’for ecologists to compare either different sampling areas or different ecological communities cooccurring in an area.Partitioning must be based upon unbiased estimates of the variation of the community composition data table that is explained by the various tables of explanatory variables.The adjusted coefficient of determination provides such an unbiased estimate in both multiple regression and canonical redundancy analysis.After partitioning,one can test the significance of the fractions of interest and plot maps of the fitted values corresponding to these fractions. 展开更多
关键词 Adjusted coefficient of determination beta diversity BIODIVERSITY canonical redundancy analysis community composition variation partitioning
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Nitrogen addition mediates the response of foliar stoichiometry to phosphorus addition: a meta-analysis 被引量:3
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作者 Chengming You Changhui Peng +9 位作者 Zhenfeng Xu Yang Liu Li Zhang Rui Yin Lin Liu Han Li Lixia Wang Sining Liu Bo Tan Paul Kardol 《Ecological Processes》 SCIE EI 2021年第1期804-816,共13页
Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and function.However,there is substantial debate on the efec... Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and function.However,there is substantial debate on the efects of P addition on foliar N and P stoichiometry,particularly under diferent levels of N addition.Thus,we conducted a global meta-analysis to investigate how N addition alters the efects of P addition on foliar N and P stoichiometry across different rates and durations of P addition and plant growth types based on more than 1150 observations.Results:We found that P addition without N addition increased foliar N concentrations,whereas P addition with N addition had no efect.The positive efects of P addition on foliar P concentrations were greater without N addition than with N addition.Additionally,the efects of P addition on foliar N,P and N:P ratios varied with the rate and duration of P addition.In particular,short-term or low-dose P addition with and without N addition increased foliar N concentration,and the positive efects of short-term or low-dose P addition on foliar P concentrations were greater without N addition than with N addition.The responses of foliar N and P stoichiometry of evergreen plants to P addition were greater without N addition than with N addition.Moreover,regardless of N addition,soil P availability was more efective than P resorption efciency in predicting the changes in foliar N and P stoichiometry in response to P addition.Conclusions:Our results highlight that increasing N deposition might alter the response of foliar N and P stoichiometry to P addition and demonstrate the important efect of the experimental environment on the results.These results advance our understanding of the response of plant nutrient use efciency to P addition with increasing N deposition. 展开更多
关键词 Ecological stoichiometry Plant nutrient regime Nutrient resorption efciency Soil N and P availability Global change Global synthesis
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Glucose-sensitivity of core-shell microspheres and their crystalline colloidal arrays 被引量:1
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作者 BAZIN Gwénaёlle ZHU Julian X. X. 《Science China Chemistry》 SCIE EI CAS 2013年第1期65-70,共6页
Thermoresponsive core-shell microspheres are prepared and functionalized with 3-aminophenylboronic acid to make them responsive to glucose.The volume phase transition of the resulting particles is shifted to a lower t... Thermoresponsive core-shell microspheres are prepared and functionalized with 3-aminophenylboronic acid to make them responsive to glucose.The volume phase transition of the resulting particles is shifted to a lower temperature and a clear swelling is caused by the presence of glucose.The particles after the functionalization preserved their capability to form crystalline colloidal arrays.The changes of their properties may be used in the design of glucose sensors. 展开更多
关键词 core-shellmicrospheres thermo-sensitivity crystalline colloidal arrays glucose sensors
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Towards a paradigm for open and free sharing of scientific data on global change science in China 被引量:4
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作者 Changhui Peng Xinzhang Song +8 位作者 Hong Jiang Qiuan Zhu Huai Chen Jing MChen Peng Gong Chang Jie Wenhua Xiang Guirui Yu Xiaolu Zhou 《Ecosystem Health and Sustainability》 SCIE 2016年第5期19-26,共8页
Despite great progress in data sharing that has been made in China in recent decades,cultural,policy,and technological challenges have prevented Chinese researchers from maximizing the availability of their data to th... Despite great progress in data sharing that has been made in China in recent decades,cultural,policy,and technological challenges have prevented Chinese researchers from maximizing the availability of their data to the global change science community.To achieve full and open exchange and sharing of scientific data,Chinese research funding agencies need to recognize that preserva-tion of,and access to,digital data are central to their mission,and must support these tasks accord-ingly.The Chinese government also needs to develop better mechanisms,incentives,and rewards,while scientists need to change their behavior and culture to recognize the need to maximize the usefulness of their data to society as well as to other researchers.The Chinese research communi-ty and individual researchers should think globally and act personally to promote a paradigm of open,free,and timely data sharing,and to increase the effectiveness of knowledge development. 展开更多
关键词 China data sharing global change science POLICY
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Polyurethanes Made from Bile Acids 被引量:1
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作者 n.levaray 朱晓夏 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第5期616-622,共7页
New polyurethanes based on bile acids were synthesized from alcohol derivatives of cholic and lithocholic acids and hexamethylene diisocyanate, in an effort to improve the biocompatibility and biodegradability of poly... New polyurethanes based on bile acids were synthesized from alcohol derivatives of cholic and lithocholic acids and hexamethylene diisocyanate, in an effort to improve the biocompatibility and biodegradability of polyurethanes through the use of natural compounds. The hydrogen bonding in the polymers is confirmed by IR spectral analysis. The glass transition temperatures of the polymers are in the range of 82-138 ℃ and degradation temperatures in the range of 267-298 ℃ as studied by thermal analyses. Thermogravimetric studies indicate that the comonomers are of equimolar amounts in the polyurethanes derived from both bile acids. 展开更多
关键词 alcohol cholic bonding amide isotherm polyol polyurethane dissolved biomedical additives
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Predominance of non-adiabatic effects in zero-point renormalization of the electronic band gap 被引量:1
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作者 Anna Miglio Véronique Brousseau-Couture +6 位作者 Emile Godbout Gabriel Antonius Yang-Hao Chan Steven G.Louie Michel Côté Matteo Giantomassi Xavier Gonze 《npj Computational Materials》 SCIE EI CSCD 2020年第1期297-304,共8页
Electronic and optical properties of materials are affected by atomic motion through the electron–phonon interaction:not only band gaps change with temperature,but even at absolute zero temperature,zero-point motion ... Electronic and optical properties of materials are affected by atomic motion through the electron–phonon interaction:not only band gaps change with temperature,but even at absolute zero temperature,zero-point motion causes band-gap renormalization.We present a large-scale first-principles evaluation of the zero-point renormalization of band edges beyond the adiabatic approximation.For materials with light elements,the band gap renormalization is often larger than 0.3 eV,and up to 0.7 eV.This effect cannot be ignored if accurate band gaps are sought.For infrared-active materials,global agreement with available experimental data is obtained only when non-adiabatic effects are taken into account.They even dominate zero-point renormalization for many materials,as shown by a generalized Fröhlich model that includes multiple phonon branches,anisotropic and degenerate electronic extrema,whose range of validity is established by comparison with first-principles results. 展开更多
关键词 ADIABATIC RENORMALIZATION PHONON
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Assembly of Highly Ordered 2D Arrays of Silver-PNIPAM Hybrid Microgels 被引量:1
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作者 Jun-ying Weng Zhuo Tang +2 位作者 关英 X.X.Zhu 张拥军 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2017年第10期1212-1221,共10页
A strategy was developed for the synthesis of highly ordered 2D arrays of Ag-PNIPAM hybrid microgel. The highly ordered 2D arrays of PNIPAM microgel were prepared by dispersing PNIPAM microgel on a charge-reversible s... A strategy was developed for the synthesis of highly ordered 2D arrays of Ag-PNIPAM hybrid microgel. The highly ordered 2D arrays of PNIPAM microgel were prepared by dispersing PNIPAM microgel on a charge-reversible substrate. The microgel spheres self-assembled into a 3D colloidal crystal, and the first 111 plane was fixed in situ onto the substrate as a result of spontaneous charge reversal of the substrate, leaving a high-quality 2D array of PNIPAM microgel. Ag nanoparticles were then synthesized in situ inside the microgel spheres by introduction of Ag+ ions into the microgel spheres and reduction with sodium borohydride. The resulting 2D arrays are highly ordered. The inter-particle distance in the array can be tuned. In addition, the method allows the synthesis of large size arrays and the use of nonplanar substrate. 展开更多
关键词 bonding conductive triazine intermolecular Hydrogen PEDOT responsive glycol polyethylene compressive
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