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A novel bibliometric and visual analysis of global geoscience research using landscape indices

Frontiers of Earth Science 2022年第2期16卷 340-351页

作者： Xin AI mingguo ma Xuemei WANG Honghai KUANG Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical SciencesSouthwest UniversityChongqing 400715China Southwest University Library Southwest UniversityChongqing 400715China Chongqing Engineering Research Center for Remote Sensing Big Data Application Southwest UniversityChongqing 400715China

The landscape index is a quantitative index which reflects characteristics of structure composition and spatial pattern in landscape studies,it is,therefore,expected to describe the spatial pattern of scientific research in bibliometric *** this study,a novel attempt to regard scientific research as a kind of‘landscape’was made,and landscape indices were improved for bibliometric analysis to measure the spatial pattern of scientific *** illustrating the feasibility of our method,global geoscience research from 1994 to 2018 was presented as a ***,spatiotemporal migration of landscape centroids was *** results indicated that global geoscience publications increased steadily and articles were highly concentrated at the country *** top 10 countries published 69.93%of total articles and 84.68%of geoscience articles were from top 20 productive *** spatial migration of centroids was mainly reflected in the longitude because of significant increasing of articles in eastern countries,especially in China with the growth rate of 747.14%.At the patch scale,the change trend of improved landscape indices verified the spatiotemporal changes of global distribution of geoscience *** the landscape scale,the strengthening of global international collaboration is the main driving forces of spatial heterogeneity of global geoscience *** study is expected to help readers to understand global trends of geoscience research in the past 25 years,and to promote the development of bibliometric analysis towards the directions of spatialization and visualization.

关键词： geoscience landscape index visualization Geographical Information System bibliometric analysis

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Formation and Collapse of Cellulose Nanocrystals and Hydrophobic Association-induced Dual Cross-linked Nanocomposite Hydrogels: A Rheological Study

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Paper And Biomaterials 2022年第3期7卷 19-29页

作者： Xiaorui Jin mingguo ma Jun Yang Beijing Key Laboratory of Lignocellulosic Chemistry College of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China

The rheological characteristics of a physical gelation system,in which cellulose nanocrystals(CNC_(s))induced the entanglement of poly(acrylic acid)(PAA)chains and partial hydrophobic association of octylphenol polyoxyethylene acrylate(OP-10-AC)branches in a micellar solution of sodium dodecyl sulfate(SDS),were *** gelation time of the physical gels decreased as the CNC content and number of hydrophobic branch units *** the gel point,the storage modulus(G')and loss modulus(G")followed the same frequency dependence(G'≈G"≈ωn),where the hydrophobic moieties attached to the side chains had a significant impact on the values of viscoelastic exponent(n).Beyond the gel point,the initial polymer solution was transformed to a solid-like gel,and the strength of the gel network was governed by associations between both the CNCs and hydrophobic *** evolution of the viscoelasticity during the gel-sol transition was monitored,demonstrating that due to a reversible arrangement of the hydrophobic units,a large proportion of physical cross-links dissociated under a thermal trigger and were reversibly reformed when the solution was cooled,while no such partial recovery was observed in the case of the single CNC-induced network systems(with no hydrophobic branches).

关键词： hydrogels cellulose nanocrystals hydrophobic association rheology

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Multi-disciplinary approaches to water systems:introduction to the special column

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Frontiers of Earth Science 2020年第2期14卷 251-255页

作者： Steven RFASSNACHT mingguo ma ESS-Watershed Science Colorado State UniversityFort CollinsCO 80523-1476USA Cooperative Institute for Research in the Atmosphere Fort CollinsCO 80523-1375USA Natural Resources Ecology Laboratory Fort CollinsCO 80523-1499USA Research Base of Karst Eco-environments at Nanchuan in Chongqing Ministry of Nature ResourcesSchool of Geographical SciencesSouthwest UniversityChongqing 400715China

1 Introduction As the human population grows,the livelihoods and well-being of a significant portion of humanity will depend even more on the ability of freshwater ecosystems to provide essential services(Vörösmarty et al.,2010),which will require the maintenance of biodiversity in these freshwater systems(Dudgeon et al.,2006).There are many competing demands on the available water resources,such as potable water,fish and wildlife habitat,agriculture,industrial use,and recreation,that are driven by different sectors;even within a specific sector there can be diverging *** example,water management of the Upper Arkansas River in Colorado has been mandated by the 1949 Arkansas River Compact between the US states of Colorado and Kansas which has led to stream-aquifer issues(Taylor and Luckey,1974),water transfers from agriculture to urban(Howe et al.,1990),and competing recreational uses(Wollmuth et al.,1985;Arkansas Basin Roundtable,2017).The recent Upper Arkansas Voluntary Flow management Program tries to balance many users,including recreation by kayakers and rafters who want to maintain streamflow(at the Wellsville gauge)at or greater than 20 m3/s as well as anglers who want lower flows in the range of 7 to 11 m3/s to maintain fish habitat(Arkansas Basin Roundtable,2017).

关键词： Upper habitat maintain

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Solvothermal Synthesis of Boehmite and γ-Alumina Nanorods

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Journal of materials Science & Technology 2008年第4期24卷 637-640页

作者： mingguo ma Yingjie ZHU Guofeng CHENG Yuehong HUANG State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Boehmite nanorods were synthesized by a solvothermal method using AICl3·6H2O in mixed solvents of water and aniline. The solvothermal time, heating temperature and the concentration of aniline have effects on the morphology of boehmite. γ-alumina nanorods were prepared by a simple thermal transformation of boehmite nanorods. A rational mechanism based on the oriented attachment is proposed for the formation of boehmite nanorods. The products were characterized by X-ray powder diffraction （XRD） and transmission electron microscopy （TEM）. Photoluminescence （PL） spectrum of the boehmite nanorods was also investigated.

关键词： Boehmite γ-Alumina Nanorods Solvothermal

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Ultrathin and Flexible CNTs/MXene/Cellulose Nanofibrils Composite Paper for Electromagnetic Interference Shielding

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Nano-Micro Letters 2019年第4期11卷 276-292页

作者： Wentao Cao Chang ma Shuo Tan mingguo ma Pengbo Wan Feng Chen Department of Orthopedics Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200072People’s Republic of China Engineering Research Center of Forestry Biomass materials and Bioenergy Beijing Key Laboratory of Lignocellulosic ChemistryCollege of Materials Science and TechnologyBeijing Forestry UniversityBeijing 100083People’s Republic of China Center of Advanced Elastomer materials State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

As the rapid development of portable and wearable devices,different electromagnetic interference(EMI)shielding materials with high efficiency have been desired to eliminate the resulting radiation ***,limited EMI shielding materials are successfully used in practical applications,due to the heavy thickness and absence of sufficient strength or ***,an ultrathin and flexible carbon nanotubes/MXene/cellulose nanofibrils composite paper with gradient and sandwich structure is constructed for EMI shielding application via a facile alternating vacuum-assisted filtration *** composite paper exhibits outstanding mechanical properties with a tensile strength of 97.9±5.0 MPa and a fracture strain of 4.6±0.2%.Particularly,the paper shows a high electrical conductivity of 2506.6 S m?1 and EMI shielding effectiveness(EMI SE)of 38.4 dB due to the sandwich structure in improving EMI SE,and the gradient structure on regulating the contributions from reflection and *** strategy is of great significance in fabricating ultrathin and flexible composite paper for highly efficient EMI shielding performance and in broadening the practical applications of MXene-based composite materials.

关键词： MXene Carbon nanotubes Cellulose nanofibrils Mechanical property Electromagnetic interference shielding

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Extraction,Purification,and Applications of Hemicellulose

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Paper And Biomaterials 2021年第3期6卷 47-60页

作者： mingguo ma Xingxiang Ji Research Center of Biomass Clean Utilization Engineering Research Center of Forestry Biomass Materials and BioenergyCollege of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China Key Laboratory of Pulp and Paper Science&Technology of Ministry of Education/Shandong Province Qilu University of Technology(Shandong Academy of Sciences)Ji'nanShandong Province250353China

In addition to cellulose and lignin,hemicellulose is an important biomass ***,hemicellulose and its derivatives and materials have attracted increasing attention owing to their unique structures,improved properties,and promising application potential,and many reports on the extraction,isolation,and modification of hemicellulose are currently *** summarized the recent developments of hemicellulose and its derivatives and materials by focusing on the extraction,purification,and modification of *** synthesis of hemicellulose-based derivatives and materials was also *** methods of extracting,isolating,and modifying hemicellulose were *** challenges related to hemicellulose extraction,purification,and application were mentioned,and directions for further research on hemicellulose were proposed.

关键词： hemicellulose extraction purification modification application

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The uncertainty analysis of the MODIS GPP product in global maize croplands

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Frontiers of Earth Science 2018年第4期12卷 739-749页

作者： Xiaojuan HUANG mingguo ma Xufeng WANG Xuguang TANG Hong YANG Chongqing Engineering Research Center for Remote Sensing Big Data Application Southwest UniversityChongqing 400715China Research Base of Karst Eco-environments at Nanchuan in Chongqing Ministry of Natural ResourcesSchool of Geographical SciencesSouthwest UniversityChongqing 400715China Northwest Institute of Eco-environment and Resources Chinese Academy of SciencesLanzhou 730000China Department of Geography and Environmental Science University of ReadingReading RG66ABUK

Gross primary productivity (GPP) is very important in the global carbon cycle. Currently, the newly released estimates of 8-day GPP at 500 m spatial resolution (Collection 6) are provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) Land Science Team for the global land surface via the improved light use efficiency (LUE) model. However, few studies have evaluated its performance. In this study, the MODIS GPP products (GPPMOD) were compared with the observed GPP (GPPEC) values from site-level eddy covariance measurements over seven maize flux sites in different areas around the world. The results indicate that the annual GPPMOD was underestimated by 6%‒58% across sites. Nevertheless, after incorporating the parameters of the calibrated LUE, the measurements of meteorological variables and the reconstructed Fractional Photosynthetic Active Radiation (FPAR) into the GPPMOD algorithm in steps, the accuracies of GPPMOD estimates were improved greatly, albeit to varying degrees. The differences between the GPPMOD and the GPPEC were primarily due to the magnitude of LUE and FPAR. The underestimate of maize cropland LUE was a widespread problem which exerted the largest impact on the GPPMOD algorithm. In American and European sites, the performance of the FPAR exhibited distinct differences in capturing vegetation GPP during the growing season due to the canopy heterogeneity. In addition, at the DE-Kli site, the GPPMOD abruptly produced extreme low values during the growing season because of the contaminated FPAR from a continuous rainy season. After correcting the noise of the FPAR, the accuracy of the GPPMOD was improved by approximately 14%. Therefore, it is crucial to further improve the accuracy of global GPPMOD, especially for the maize crop ecosystem, to maintain food security and better understand global carbon cycle.

关键词： MODIS GPP eddy covariance maize cropland validation improvement

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Comparing the seasonal variation of parameter estimation of ecosystem carbon exchange between alpine meadow and cropland in Heihe River Basin,northwestern China

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Research in Cold and Arid Regions 2015年第3期7卷 216-228页

作者： HaiBo Wang mingguo ma Heihe Remote Sensing Experimental Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Remote Sensing of Gansu Province Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences School of Geographical Sciences Southwest University(Beibei District)

Grasslands and agro-ecosystems occupy one-third of the global terrestrial area. However, great uncertainty still exists about their contributions to the global carbon cycle. This study used various combinations of a simple ecosystem respiration model and a photosynthesis model to simulate the influence of different climate factors, specifically radiation, temperature, and moisture, on the ecosystem carbon exchange at two dissimilar study sites. Using a typical alpine meadow site in a cold region and a typical cropland site in an arid region as cases, we investigated the response char- acteristics of productivity of grasslands and croplands to different environmental factors, and analyzed the seasonal change patterns of different model parameters. Parameter estimations and uncertainty analyses were performed based on a Bayesian approach. Our results indicated that：（1） the net ecosystem exchange （NEE） of alpine meadow and seeded maize during the growing season presented obvious diurnal and seasonal variation patterns. On the whole, the alpine meadow and seeded maize ecosystems were both apparent sinks for atmospheric CO2; （2） in the daytime, the mean NEE of the two ecosystems had the largest values in July and the lowest values in October. However, overall carbon uptake in the cropland was greater than in the alpine meadow from June to September; （3） at the alpine meadow site, temperature was the main limiting factor influencing the ecosystem carbon exchange variations during the growing season, while the sensitivity to water limitation was relatively small since there is abundant of rainfall in this region; （4） at the cropland site, both temperature and moisture were the most important limiting factors for the variations of ecosystem carbon exchanges during the growing season; and （5） some parameters had an obvious characteristic of seasonal patterns, while others had only small seasonal variations.

关键词： ecosystem carbon flux ecosystem respiration gross ecosystem productivity climatic factors alpine meadow farmland ecosystem

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Heterogeneous sea-level rises along coastal zones and small islands

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Science Bulletin 2019年第11期64卷 748-755页

作者： Guoshuai Li Xin Li Tandong Yao Tao Che Hong Yang mingguo ma Haipeng Zhao Xiaoduo Pan Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Dapartment of Geography and Environmental Science University of ReadingWhiteknightsReading RC6 6ABUK Research Base of Karst Eco-environments at Nanchuan in Chongqing Ministry of Natural ResourcesSchool of Geographical SciencesSouthwest UniversityChongqing 400715China Department of Earth and Environmental Systems Indiana State UniversityTerre HauteIN 47809USA

Coastal zones and many small islands are highly susceptible to sea-level rise(SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to millions of people worldwide. The coastal zones and small islands affected by SLR are likely to suffer from submergence, flooding and erosion in the future. However, very few studies have addressed the heterogeneity in SLR changes and the potential risk to coastal zones and small islands. Here we used the mean sea level(MSL) derived from satellite altimetry data to analyse the trends and accelerations of SLRs along global coastal zones and small islands. We found that except for the Antarctic coastal zone, the annual MSL within 50 km of the coasts presented an increasing trend of 3.09 ± 0.13 mm a^-1 but a decreasing acceleration of -0.02 ± 0.02 mm a^-2 from 1993 to 2017. The highest coastal MSL trend of3.85 ± 0.60 mm a^-1 appeared in Oceania, and the lowest trend of 2.32 ± 0.37 mm a^-1 occured in North America. Africa, North America and South America showed acceleration trends, and Eurasia, Australia and Oceania had deceleration trends. Further, MSLs around global small islands reflected an increasing trend with a rate of 3.01 ± 0.16 mm a^-1 but a negative acceleration of -0.02 ± 0.02 mm a^-2. Regional heterogeneity in the trends and accelerations of MSLs along the coasts and small islands suggests that stakeholders should take discriminating precautions to cope with future disadvantageous impacts of the SLR.

关键词： Sea-level rise Coastal zones Small islands Heterogeneity

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The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE Qifeng DONG Yunpeng CAI Yuanfeng ZHAI mingguo XIAO Aifang ZHANG Hong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still *** results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock *** samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of *** the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type *** the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization *** values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement *** comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

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