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Petrological Characteristics and Genesis of the Central Indian Ocean Basin Basalts

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1154-1170页

作者： Pranab DAS Sridhar D.IYER Sugata HAZRA National institute of Oceanography(Council of Scientific and Industrial Research)Dona Paula Goa 403004India Department of Applied Geology Indian School of MinesDhanbad 826004India School of Oceanographic studies Jadavpur UniversityKolkata 700032India

The Central Indian Ocean Basin （CIOB） basalts are plagioclase-rich, while olivine and pyroxene are very few. The analyses of 41 samples reveal high FeOT （～10-18 wt%） and TiO 2 （～1.4-2.7 wt%） indicating a ferrobasaltic composition. The basalts have high incompatible elements （Zr 63-228 ppm; Nb ～1-5 ppm; Ba ～15-78 ppm; La ～3-16 ppm）, a similar U/Pb （0.02-0.4） ratio as the normal midoceanic basalt （0.16±0.07） but the Ba/Nb （12.5-53） ratio is much larger than that of the normal midoceanic ridge basalt （～5.7） and Primitive Mantle （9.56）. Interestingly almost all of the basalts have a significant negative Eu anomaly （Eu/Eu＊=0.78-1.00） that may have been a result of the removal of feldspar and pyroxene during crystal fractionation. These compositional variations suggest that the basalts were derived through fractional crystallization together with low partial melting of a shallow seated magma.

关键词： basalts Genesis Central Indian Ocean Basin

Experimental and theoretical study on the dynamic effective stress of loaded gassy coal during gas release

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International Journal of Mining Science and Technology 2023年第3期33卷 339-349页

作者： Bing Zhang Hanpeng Wang Peng Wang Guofeng Yu Shitan Gu School of Qilu transportation Shandong UniversityJinan 250061China Geotechnical and Structural Engineering Research Center Shandong UniversityJinan 250061China Coal Mining National Engineering Technology Research institute Huainan 232001China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

In the process of mining coalbed methane(CBM),an unsteady state often arises due to the rapid extraction,release and pressure relief of *** this case,the effective stress of coal changes dynamically,affecting the stability of the gassy coal *** this paper,gas release tests of gassy coal under conventional triaxial compression were performed,and the dynamic effective stress(DES)during gas release was obtained indirectly based on a constitutive equation and deformation of *** results show that the maximum increases in DES caused by the release of free gas and adsorbed gas under the stress of 1.1 MPa were 0.811 and 5.418 MPa,respectively,which seriously affected the stress state of the *** the gas release,the free gas pressure and the adsorbed gas volume were the parameters that directly affected the DES and showed a positive linear relationship with the DES with an intercept of *** DES of the coal sample increased exponentially with time,which was determined by the contents of free and adsorbed *** on the experimental results and theoretical analysis,an effective stress model was obtained for loaded gassy coal during gas *** results of verification indicated accuracy greater than 99%.

关键词： Gassy coal Dynamic effective stress Gas release Gas-solid coupling Mathematical model

Field Modeling Method for Identifying Urban Sphere of Influence:A Case Study on Central China

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Chinese Geographical Science 2010年第4期20卷 353-362页

作者： DENG Yu LIU Shenghe WANG Li MA Hanqing WANG Jianghao institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China institute of Policy and Management Chinese Academy of Sciences Beijing 100190 China Center for Interdisciplinary studies of Natural and Social Sciences Chinese Academy of Sciences Beijing 100190 China

With rapid development of urbanization and regional interaction and interdependence, regional urban agglomeration planning becomes more and more important in China, in order to promote integrated development of various cities with close interrelationship. However, it is still arguable academically on how to define the boundary or which cities to be included for the urban agglomeration of a region. This paper aims to shed lights on how to identify urban spheres of influence scientifically by introducing field modeling method and by practicing a case study on 168 cities in Central China. In our field modeling method, the influence intensities of cities were measured by a compre-ensive index and urban spheres of influence were represented spatially by field intensity. Then, their classification and spatial distribution characteristics of study area in 2007 were identified and explored by using GIS and statistical methods. The result showed that： 1） Wuhan is the absolute dominant city in Central China; 2） the provincial capital cities dominate their own provinces and there are no other lower grade agglomeration centers; and 3） the basic types of organization form of urban sphere of influence are single-polar type, agglomeration type, close-related group type and loose-related group type.

关键词： Central China urban sphere of influence urban influence index field intensity urban influence intensity

Links between COVID-19 and Parkinson’s disease/Alzheimer’s disease:reciprocal impacts,medical care strategies and underlying mechanisms

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Translational Neurodegeneration 2023年第1期12卷 824-848页

作者： Pei Huang Lin-Yuan Zhang Yu-Yan Tan Sheng-Di Chen Department of Neurology and institute of Neurology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Neurology Shanghai General HospitalShanghai 200080China Lab for Translational Research of Neurodegenerative Diseases Shanghai Institute for Advanced Immunochemical Studies(SIAIS)Shanghai Tech UniversityShanghai 201210China

The impact of coronavirus disease 2019(COVID-19)pandemic on patients with neurodegenerative diseases and the specific neurological manifestations of COVID-19 have aroused great ***,there are still many issues of concern to be ***,we review the current literature on the complex relationship between COVID-19 and neurodegenerative diseases with an emphasis on Parkinson’s disease(PD)and Alzheimer’s disease(AD).We summarize the impact of COVID-19 infection on symptom severity,disease progression,and mortality rate of PD and AD,and discuss whether COVID-19 infection could trigger PD and *** addition,the susceptibility to and the prognosis of COVID-19 in PD patients and AD patients are also *** order to achieve better management of PD and AD patients,modifications of care strategies,specific drug therapies,and vaccines during the pandemic are also *** last,mechanisms underlying the link of COVID-19 with PD and AD are reviewed.

关键词： COVID-19 SARS-CoV-2 Parkinson’s disease Alzheimer’s disease Mechanism

Research on the Mechanism of the Spatial Contagion of Global Financial Crises: From the Perspective of Pure Contagion

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Chinese Journal of Urban and Environmental studies 2018年第1期6卷 95-110页

作者： WU Zhanyun institute for Urban and Environmental studies Chinese Academy of Social Sciences

In the post financial crisis era, the contagion of a financial crisis remains an important *** upon the idea of absolute physical space in classical cartography, this paper attempts to construct the space of political and economic systems for the contagion of financial crisis through a decomposition and re-synthesis of Index of Economic Freedom. It then utilizes the Spatial Autocorrelation Model to analyze the characteristics of the spatial distribution, structure, and interactions of the contagion. The empirical findings show that the contagion of international financial crisis has dependence on both geographical space and space of economic systems, and the spatial dependence on the latter is more significant and intense than that on the *** findings verify the pure contagion of a financial crisis, that is, similar political and economic systems rather than geographical proximity among countries are more likely to lead to the contagion of a financial crisis.

关键词： Financial crisis spatial autocorrelation pure contagion economic system space

A review of geophysical studies on the Mongolian Plateau

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Earthquake Science 2024年第3期37卷 224-240页

作者： Lei Zhang Zhouchuan Huang Xiaodong Song Qingju Wu SinoProbe Laboratory School of Earth and Space SciencesPeking UniversityBeijing 100871China Hebei Hongshan National Observatory on Thick Sediments and Seismic Hazards Peking UniversityBeijing 100871China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China institute of Geophysics China Earthquake AdministrationBeijing 100081China

The Mongolian Plateau in Central Asia is an intracontinental tectonic system far from active plate *** its distance from these boundaries,the plateau is characterized by intense crustal deformation accompanied by voluminous Cenozoic volcanism and active modern ***,the intraplate deformation mechanism has long been debated owing to the scarcity of observations and contradictions between different *** recent years,growing geophysical studies have been conducted on the Mongolian Plateau,providing constraints on its lithospheric structure and ***,we review the geophysical research on the Mongolian Plateau over the last decade,including seismological,geodetic,gravity,magnetotelluric,and geodynamic *** review aims to(a)describe crustal and mantle structures based on multiscale seismic images;(b)describe deformation patterns based on seismic anisotropy,focal mechanisms,and global positioning system(GPS)observations;and(c)discuss the mechanisms behind intraplate deformation,volcanism,and seismic activity across the Mongolian *** images show that the crustal structure of the plateau has significant east-west *** blocks in the western Mongolian Plateau have thick crusts,including the Altai Mountains,Hovsgol Rift,and Hangay *** lithospheric deformation across the Mongolian Plateau has strong lateral variation,with NE-SW shortening in the Altai Mountains and W-E or NW-SE shear deformation in the Hangay Dome region and the eastern *** varied deformation may result from the superposition of multiple mechanisms,including far-field stress in the Altai Mountains,mantle upwelling,and mantle flow in the Hangay Dome ***,it is difficult to identify the geodynamics of the formation of the entire Mongolian Plateau because the deformation is too complicated,and the present models are not sufficient and are always ***,this review encompasses recent advances in seismic observa

关键词： Mongolian Plateau Central Asia seismic tomography crust-mantle structure intraplate deformation

Optical and SAR image registration based on improved nonsubsampled wavelet transform for sea islands

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Acta Oceanologica Sinica 2014年第5期33卷 86-95页

作者： SHI Wei SU Fenzhen WANG Ruirui LU Yongduo institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Collaborative Innovation Center of South China Sea studies Nanjing University Beijing Forestry University National Marine Environmental Forecasting Center State Oceanic Administration

Homologous feature point extraction is a key problem in the optical and synthetic aperture radar （SAR） image registration for islands. A new feature point extraction method using a threshold shrink operator and non-subsampled wavelet transform （TSO-NSWT） for optical and SAR image registration was proposed. Moreover, the matching for this proposed feature was different from the traditional feature matching strategies and was performed using a similarity measure computed from neighborhood circles in low-frequency bands. Then, a number of reliably matched couples with even distributions were obtained, which assured the accuracy of the registration. Application of the proposed algorithm to SPOT-5 （multi-spectral） and YG-1 （SAR） images showed that a large number of accurately matched couples could be identified. Additionally, both of the root mean square error （RMSE） patterns of the registration parameters computed based on the TSO-NSWT algorithm and traditional NSWT algorithm were analyzed and compared, which further demonstrated the effectiveness of the proposed algorithm. The algorithm can supply the crucial step for island image registration and island recognition.

关键词： image registration islands South China Sea wavelet transform threshold shrink operator

Comparison of pan evaporation and actual evaporation estimated by land surface model in Xinjiang from 1960 to 2005

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Journal of Geographical Sciences 2009年第4期19卷 502-512页

作者：刘波马柱国徐晶晶肖子牛 Chinese Academy of Sciences Key Laboratory of Regional Climate-Environment Research for Temperate East Asia START TEA for East AsiaInstitute of Atmospheric PhysicsCAS Laboratory for Climate studies National Climate CenterChina Meteorological Administration

Pan evaporation,an indictor of potential evaporation,has decreased during the last several decades in many parts of the world;the trend is contrary to the expectation that the increase of actual evaporation will accompany global warming,known as the pan evaporation *** is the essential relationship between pan evaporation and actual evaporation? This is still an uncertain *** this paper,the trends of pan evaporation and actual evaporation are investigated using observational data and observation-constrained simulation results using NCAR Community Land Model(CLM) in Xinjiang from 1960 to *** analysis suggests that the decreasing trend of annual pan evaporation accompanies the increasing trend of annual actual evaporation,the tendencies of them both have statistical significance(at 99% level and at 95% level,respectively).We also find that there is the same turning point in precipitation,pan evaporation and actual evaporation of 1986,and either before the point or after,pan evaporation has inverse trend comparing with actual evaporation and *** above analysis indicates that pan evaporation and actual evaporation have complementary *** results support the issue of evaporation paradox described by Brutsaert and Parlange(1998) and suggest that decrease of pan evaporation indicates an increase of actual evaporation in Xinjiang in the past half *** correlation analysis shows that diurnal temperature range(DTR),wind speed,low cloud cover and precipitation are the most likely driving forces for the reduced pan evaporation and the ascending actual evaporation.

关键词： Xinjiang pan evaporation actual evaporation numeral simulation

A Challenging Approach to Improve the Low Affinity of Acrylic Fibres to Be Successfully Dyed with a Bio-Colorant Extracted from Grape Marc

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Journal of Renewable Materials 2019年第3期7卷 289-300页

作者： Noureddine Baaka Manel Ben Ticha Wafa Haddar Mohamed Farouk Mhenni University of Monastir Faculty of Sciences of MonastirResearch Unity of Applied Chemistry and Environment5000 MonastirTunisia National Engineering School of Monastir 5019 MonastirTunisia Higher institute of Technological studies 5070Ksar HellalMonastirTunisia

Acrylic fibres are highly crystalline and non-polar polymers,which makes their dyeing a very difficult step that poses real technical *** order to overcome this concern,it is intended in this paper to modify acrylic fibers by different methods namely cationisation using the Crosscolor DRT then amidoximation using hydroxylamine hydrochloride and ammonium *** resulted samples were dyed then with the bio-colorant extracted from grape *** effect of the pretreatment on fibers fine structure using X-ray diffraction and the scanning electron microscope(SEM)images and its correlation with the colour strength of the dyed fabrics was *** dyeing parameters,such as dye bath pH and temperature on the performances of this dyeing process were *** dyeing qualities and new shades varying from brown to grey and dark green have been obtained following process optimization,mordanting and modification of acrylic fibers by the technique of cationisation.

关键词： Modified acrylic fibers grape marc bio-colorant mordant.