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Crustal structure of the western Indian shield: Model based on regional gravity and magnetic data

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Geoscience Frontiers 2013年第6期4卷 717-728页

作者： Suman Kilaru Bandaru Karunakar Goud Vijay Kumar Rao National geophysical research institute

Regional surface gravity data and global satellite magnetic data have been utilized to generate a preliminary model of the crustal structure along a southwest-northeast profile （Gadra-Fatehpur） through western *** study area represents the western part of the Indian continental landmass which has undergone several major episodes of repeated subduction/collision,plume traces and rifting from Archaean to recent *** temporal and spatial relationship between the various geotectonic provinces is quite complex,thereby limiting the emergence of a suitable crustal structure model for this *** of the Malani Igneous Suite （MIS）,a product of bimodal volcanism （～780 Ma）,and considered to be the third largest felsic magmatic province of the world,is evident along the profile and also to the southwest of the study *** easternmost part of the profile is close to the DAFB （Delhi Aravalli Fold Belt）,a Proterozoic orogenic *** study probes the geometry of the different crustal units in terms of density and susceptibility variations in order to decipher the imprints of the major tectonic processes the region has *** order to decipher the crustal geometry of the Gadra-Fatehpur profile,two NW-SE gravity and magnetic profile vertical sections （A-A＇ in the south and B-B＇ in the north） are modelled on the basis of the constraints provided from previous seismic *** crustal model of the Gadra-Fatehpur profile is composed of alluvium,Tertiary sediments,MIS,Marwar Supergroup,low-density layers （LDLs） and the middle-lower crustal layers,with a distinct change in configuration from the southwest to *** Moho dips from SW to NE,the MIS in the SW gives way to the thick pile of the Marwar Supergroup to the *** evolution of MIS has been suggested to have occurred as a consequence of delamination of the upper *** are incorporated in Gadra-Fatehpur *** the SW,LDL （2550 kg/m3） lies below the MIS in the NE,another LDL （2604

关键词： Western Indian shield Gravity and magnetic modelling MIS Delamination Bimodal volcanism

Rare earth elements:A review of applications, occurrence,exploration,analysis,recycling, and environmental impact

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Geoscience Frontiers 2019年第4期10卷 1285-1303页

作者： V.Balaram CSIR-National geophysical research institute

Rare earth elements(REE)include the lanthanide series elements(La,Ce,Pr,Nd,Pm,Sm,Eu,Gd,Tb,***,Er,Tm,Yb,and Lu)plus Sc and *** these metals have become very critical to several modern technologies ranging from cell phones and televisions to LED light bulbs and wind *** article summarizes the occurrence of these metals in the Earth’s crust,their mineralogy,different types of deposits both on land and oceans from the standpoint of the new data with more examples from the Indian *** addition to their utility to understand the formation of the major Earth ***-faceted updates on the applications of REE in agriculture and medicine including new emerging ones are *** hazards including human health issues due to REE mining and large-scale dumping of e-waste containing significant concentrations of REE are *** strategies for the future supply of REE including recent developments in the extraction of REE from coal fired ash and recycling from e-waste are *** developments in individual REE separation technologies in both metallurgical and recycling operations have been *** outline of the analytical methods for their precise and accurate determinations required in all these studies,such as,Xray fluorescence spectrometry(XRF),laser induced breakdown spectroscopy(LIBS),instrumental neutron activation analysis(INAA),inductively coupled plasma optical emission spectrometry(ICP-OES),glow discharge mass spectrometry(GD-MS),inductively coupled plasma mass spectrometry(including ICP-MS,ICP-TOF-MS,HR-ICP-MS with laser ablation as well as solution nebulization)and other instrumental techniques,in different types of materials are presented.

关键词： REE Mineralogy Deposits Metallurgy Environmental Recycling

Experimental Study on Wear and Spalling Behaviors of Railway Wheel

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Chinese Journal of Mechanical Engineering 2013年第6期26卷 1243-1249页

作者： WANG Wenjian GUO Jun LIU Qiyue Tribology research institute Southwest Jiaotong University

The current researches of the wear and spalling behaviors of wheel/rail materials focus on the field investigation rather than the mechanism. However, it is necessary and significant for clarifying the mechanism and relationship between the wear and spalling damage of railway wheel to test and reproduce the wheel damages in laboratory. The objective of this paper is to investigate the wear and spalling damage behaviors of railway wheel using a JD-1 wheel/rail simulation facility, which consists of a small wheel serving as rolling stock wheel, and a larger wheel serving as rail. The damage process of wheel roller is explored in terms of the creep ratio, axle load, and carbon content by means of various microscopic examinations. The experimental results show that the wear volume growth of wheel roller is proved to be proportional to the increase of the creep ratio and normal load between simulating wheel and rail. The increase of carbon content of wheel material causes a linear reduction in the wear volume. The microscopic examinations indicate that the rolling wear mechanism transfers from abrasive wear to adhesive and fatigue wear with an increase of tangential friction force, which results in the initiation of fatigue crack, and then aggravates spalling damage on the wheel roller surface. The surface hardness of material depends strongly upon its carbon content. The decrease of the carbon content of wheel material may alleviate spalling damage, but can cause a significant growth in the wear volume of wheel roller. Therefore, there is a competitive relationship between the wear and spalling damage of wheel material. This research proposes an important measure for alleviating or preventing the wear and spalling damage of railway wheel material.

关键词： wear spalling content carbon railway wheel wear mechanism

Characterization of the imprinting and expression patterns of ZAG2 in maize endosperm and embryo

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The Crop Journal 2015年第1期3卷 74-79页

作者： Chaoxian Liu Jiuguang Wang Xiupeng Mei Xiaojing Deng Tingting Yu Xiaoli Liu Guoqiang Wang Zhizhai Liu Yilin Cai Maize research institute Southwest University

ZAG2 has been identified as a maternally expressed imprinted gene in maize *** study revealed that paternally inherited ZAG2 alleles were imprinted in maize endosperm and embryo at 14 days after pollination(DAP), and consistently imprinted in endosperm at 10, 12, 16, 18, 20, 22, 24, 26, and 28 DAP in reciprocal crosses between B73 and Mo17. ZAG2 alleles were also imprinted in reciprocal crosses between Zheng 58 and Chang7-2 and between Huang C and 178. ZAG2 alleles exhibited differential imprinting in hybrids of 178 × Huang C and B73 × Mo17, while in other hybrids ZAG2 alleles exhibited binary imprinting. The tissue-specific expression pattern of ZAG2 showed that ZAG2 was expressed at a high level in immature ears, suggesting that ZAG2 plays important roles in not only kernel but ear development.

关键词： Gene imprinting ZAG2 Expression pattern Endosperm Embryo

Community Tourism as Practiced in the Mountainous Qiang Region of Sichuan Province,China-a Case Study in Zhenghe Village

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Journal of Mountain Science 2008年第2期5卷 140-156页

作者： ZHOU Lianbin LIU Kaibang southwest institute for Nationalities research Southwest University for Nationalities Sichuan China

In China, community tourism is still a relatively new phenomenon, but the villagers of a small Qiang village in the Qiang Autonomous County of Beichuan in southwestern Sichuan have initiated tourism in a way which conforms to the basic theory of community tourism development. This demonstrates that community tourism possesses a strength and vitality that can promote the development of tourism in the rural and mountainous areas. In the district of Zhenghe Village, the tourism industry, based on the community tourism model, is the mainstay of its economy. The practice of community tourism in the village not only promotes the economic development of the village community, but also leads to the protection of the mountainous natural environment and of the culture of the Qiang people. This paper investigates the development process of community tourism in Zhenghe and shows how the local residents participate in this process. It also looks at how profits have been distributed within the community. It demonstrates that community tourism is a correct choice by the Zhenghe people as they have dearly been moving from poverty to prosperity, while the local ecology and environment have been simultaneously protected. The authors hope that other minority villages with similar local conditions and natural resources will be able to use this example to develop their own community tourism.

关键词： Community protection Qiang minority Sichuan China tourism environmental region Zhenghe Village

Logging-based assessment of low-resistivity oil zones:A case study from Sudan

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Energy Geoscience 2023年第2期4卷 82-90页

作者： Li Chunmei Wu Furong Zang Dianguang Peng Cai Guo Hongxi Li Jie southwest geophysical research institute BGP Inc.China National Petroleum CorporationChengduChina Petro China southwest Oil&Gas Feild Company ChengduChina

The reservoirs in the N oilfield in Sudan feature a complex sedimentary environment,which has led to a widespread development of low-resistivity oil zones,accounting for as high as 37%of the total oil *** this case,a large number of oil zones will be misinterpreted using conventional *** on the analysis of the core data and logging curves of the study area,this study concludes that the lowresistivity oil zones are formed mainly due to the high irreducible water saturation caused by the high content of illite and smectite and complex pore structure,the additional electrical conductivity induced by clay minerals,and the difference in formation water salinity between the oil zones and water ***,four methods are proposed to qualitatively identify these oil zones and water zones,namely the relationship analysis of five reservoir properties,cross-plotting of sensitive parameters,analysis of pressure testing data,and multi-well ***,the study quantitatively calculates the initial oil saturation using the capillary pressure data,thus avoiding the conventional empirical saturation formulas depending on electrical resistivity and solving the difficulty in calculating oil saturation of low-resistivity oil ***,precise logging processing and interpretation of 95 wells in the study area are conducted using the above-mentioned comprehensive assessment system for low-resistivity oil *** a result,59 oil zones are newly discovered in 43 ***,it is recommended that 17 oil zones in 12 wells should be tested,of which 11 oil zones have been tested as recommended,all proven to be high production oil zones after *** coincidence rate of logging interpretation increases from 75%to 94.3%,and the original oil in place(OOIP)increases by 57.42 million *** these indicate that the assessment system proposed is suitable for low-resistivity zones.

关键词： Low-resistivity oil zone Cause analysis Qualitative identification J-function Saturation

Physiological changes and expression characteristics of ZIP family genes under zinc def iciency in navel orange(Citrus sinensis)

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Journal of Integrative Agriculture 2016年第4期15卷 803-811页

作者： XING Fei FU Xing-zheng WANG Nan-qi XI Jian-long HUANG Yi ZHOU Wei LING Li-li PENG Liang-zhi Citrus research institute Southwest University College of Horticulture and Landscape Southwest University

Zinc （Zn） deficiency is widespread among citrus plants, but information about the mechanisms for Zn deficiency response in these plants is scarce. In the present study, different navel orange （Citrus sinensis （L.） Osbeck） leaves with various yellowing levels were sampled in our experimental orchard, and upon estimation of nutrient contents, Zn deficiencies were diagnosed as mild, moderate, and severe. Further analysis of chlorophyll content, photosynthetic characteristics, antioxidant enzyme activities, and expression levels of Zn/Iron-regulated transporter-like protein （ZIP） family genes were conducted in the sampled Zn-deficient leaves. The results showed that chlorophyll contents and net photosynthetic rate （Pn） seemed to decrease with reduced Zn contents. In addition, comparison of severe Zn-deficient and normal leaves revealed that activities of peroxidase （POD） and catalase （CAT） increased significantly, whereas that of Zn-containing enzymes such as Cu/Zn superoxide dismutase （Cu/Zn-SOD） significantly reduced with decreasing Zn contents. As expected, expression of the ZIP family genes, ZIP1, ZIP3, and ZIP4, was induced by Zn deficiencies. These results deepen our understanding of Zn deficiency in citrus plants as well as provide useful preliminary information for further research.

关键词： navel orange Zn deficiency physiological changes ZIP family gene expression

Emerging Challenges in Atolls for Sustainable Groundwater Management

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地学前缘 2009年第S1期16卷 22-23页

作者： Pallavi Banerjee V.S.Singh National geophysical research institute

Tropical islands,about 50000 in number,are distributed over the Pacific,Indian and Atlantic *** groundwater resources in the form of lens shaped aquifers,in atolls,are extremely vulnerable to natural processes and human *** increasing population on these islands has worsened the groundwater demand supply ratio significantly. This deteriorating ground water condition has come

关键词： coral islands groundwater numerical modeling groundwater level sea level

Integrated application of gravity,aeromagnetic,and electromagnetic methods in exploring the Ganzi geothermal field,Sichuan Province,China

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Energy Geoscience 2023年第4期4卷 119-127页

作者： Hong Li Sinopec geophysical research institute Co. LtdChina

The Ganzi geothermal field is located in the Songpan-Ganzi orogenic belt in Sichuan *** hot springs are exposed along the Yalahe valley in Ganzi geothermal field,which is a favorable area for hightemperature geothermal resource ***,the geological model of heat exchange,the regional structure controlling hydrothermal convection and the development model of geothermal reservoirs are still ***,further studies are necessary to meet the geothermal exploration requirements in the middle and deep strata of this geothermal *** this study,a geological model of the geothermal system of Ganzi geothermal field is *** are convinced that there exists a hydrothermal convection system in the Ganzi geothermal field,the heat transfer of which is accomplished through deep-rooted major ***,the identification of deep-rooted major faults and the description of geothermal reservoirs are the research objects of the integrated geophysical *** main factors controlling the geothermal reservoirs in the deep-rooted Xianshuihe major fault and Yalahe fault zones are analyzed by using gravity,aeromagnetic,and electromagnetic methods and *** analysis results of regional gravity and aeromagnetic anomalies show that the Xianshuihe major fault has produced obvious gravity and aeromagnetic anomalies on the surface,and thus the position and strike of this fault can be accurately predicted by inversion of the aeromagnetic *** reservoirs show low-resistivity anomalies in the electromagnetic *** inversion results of the controlled source audio-frequency magnetotelluric(CSAMT)data show that geothermal reservoirs are mainly developed along the Yalahe valley,and the west side of the valley is more favorable for geothermal *** study is of guiding significance to the efficient exploitation and utilization of the Ganzi geothermal field.

关键词： Ganzi geothermal field Geothermal reservoir Geothermal resource Gravity-aeromagnetic-electromagnetic anomaly