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North China Petrochemical Advances Ecological and Cultural Development to Create a New“Yanzhao Pearl”by Baiyangdian
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作者 Feng Jide Song Xiaodan 《China Oil & Gas》 2025年第3期82-83,共2页
State-owned enterprises are key players in building ecological civilization in the new era.Promoting ecological civilization requires not only institutional mechanisms and systems but also the leadership of ecological... State-owned enterprises are key players in building ecological civilization in the new era.Promoting ecological civilization requires not only institutional mechanisms and systems but also the leadership of ecological culture.North China Petrochemical Company is situated in the heart of the Beijing-Tianjin-Hebei region,merely 3 km from Xiongan New Area and just over a hundred kilometers from the capital,Beijing. 展开更多
关键词 building ecological civilization north china petrochemical company ecological civilization leadership ecological institutional mechanisms systems beijing tianjin hebei region ecological culture xiongan new area
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Late Paleozoic-Early Mesozoic Tectonic Evolution of the Zongwulong Shan-Qinghai Nanshan Tectonic Belt in the Northern Qaidam Continent,Northern Xizang
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作者 Yonghui Zhao Chen Wu +2 位作者 Jie Li Peter J.Haproff Lin Ding 《Journal of Earth Science》 2025年第4期1355-1379,共25页
The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Xizang Plateau experienced a protracted tectonica history,including the openings and closures of the Proto-and Paleo-Tethyan Oceans.Although the tecton... The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Xizang Plateau experienced a protracted tectonica history,including the openings and closures of the Proto-and Paleo-Tethyan Oceans.Although the tectonic belt has been extensively studied,details regarding the tectonic processes involved in its development remain controversial.To better constrain the tectonic processes of this tectonic belt,we conducted detailed field geological mapping,zircon U-Pb geochronology,and whole-rock geochemical and Sr-Nd isotopic analyses.Our results show that intrusive rocks in the tectonic belt crystallized in ca.292-233 Ma,perhaps in an arc/subduction setting.Geochemical and Sr-Nd isotopic data suggest that Early Permian-Late Triassic ultramaficintermediate intrusions were sourced from the enriched mantle,whereas intermediate-acidic rocks were sourced from mixed crust-mantle.We present the tectonic model that involves:(1)Early Devonian-Early Permian intracontinental extension occurred in the northern margin of the Qaidam continent(ca.416-292 Ma);(2)Early Permian-Late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism(ca.292-233 Ma);and(3)subsequent Late Triassic intracontinental extension(ca.233-215 Ma).Our results suggest that the Late Paleozoic-Early Mesozoic development of the Zongwulong Shan-Qinghai Nanshan was related to the opening,subduction,and slab retreat of the Paleo-Tethyan Ocean,which has key implications for the tectonic evolution of the northern Tibetan Plateau. 展开更多
关键词 Paleo-Tethyan Ocean northern Tibetan Plateau Late Paleozoic-Early Mesozoic magmatism Zongwulong Shan-Qinghai Nanshan tectonic belt subduction-collision tectonics
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Earthquake detection probabilities and completeness magnitude in the northern margin of the Ordos Block
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作者 Zhang Fan Yang Xiao-Zhong Cui Feng-Zhi 《Applied Geophysics》 SCIE CSCD 2024年第4期777-793,881,共18页
The assessment of the completeness of earthquake catalogs is a prerequisite for studying the patterns of seismic activity.In traditional approaches,the minimum magnitude of completeness(MC)is employed to evaluate cata... The assessment of the completeness of earthquake catalogs is a prerequisite for studying the patterns of seismic activity.In traditional approaches,the minimum magnitude of completeness(MC)is employed to evaluate catalog completeness,with events below MC being discarded,leading to the underutilization of the data.Detection probability is a more detailed measure of the catalog's completeness than MC;its use results in better model compatibility with data in seismic activity modeling and allows for more comprehensive utilization of seismic observation data across temporal,spatial,and magnitude dimensions.Using the magnitude-rank method and Maximum Curvature(MAXC)methods,we analyzed temporal variations in earthquake catalog completeness,finding that MC stabilized after 2010,which closely coincides with improvements in monitoring capabilities and the densification of seismic networks.Employing the probability-based magnitude of completeness(PMC)and entire magnitude range(EMR)methods,grounded in distinct foundational assumptions and computational principles,we analyzed the 2010-2023 earthquake catalog for the northern margin of the Ordos Block,aiming to assess the detection probability of earthquakes and the completeness of the earthquake catalog.The PMC method yielded the detection probability distribution for 76 stations in the distance-magnitude space.A scoring metric was designed based on station detection capabilities for small earthquakes in the near field.From the detection probabilities of stations,we inferred detection probabilities of the network for diff erent magnitude ranges and mapped the spatial distribution of the probability-based completeness magnitude.In the EMR method,we employed a segmented model fitted to the observed data to determine the detection probability and completeness magnitude for every grid point in the study region.We discussed the sample dependency and low-magnitude failure phenomena of the PMC method,noting the potential overestimation of detection probabilities for lower magnitudes and the underestimation of MC in areas with weaker monitoring capabilities.The results obtained via the two methods support these hypotheses.The assessment results indicate better monitoring capabilities on the eastern side of the study area but worse on the northwest side.The spatial distribution of network monitoring capabilities is uneven,correlating with the distribution of stations and showing significant diff erences in detection capabilities among diff erent stations.The truncation eff ects of data and station selection aff ected the evaluation results at the edges of the study area.Overall,both methods yielded detailed descriptions of the earthquake catalog,but careful selection of calculation parameters or adjustments based on the strengths of diff erent methods is necessary to correct potential biases. 展开更多
关键词 magnitude of completeness northern margin of the Ordos Block PMC method EMR method earthquake detection probability
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Urban Spatial Form Optimization Strategies Based on the Principle of Climate Adaptability of Regional Architecture: A Case Study of Traditional Cave Dwelling Villages in Northern Shaanxi Province
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作者 QI Zizhuo YANG Xin 《Journal of Landscape Research》 2024年第3期1-7,共7页
A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate ... A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate and resources.This paper examines the principles of climate adaptability embedded in the site layout and spatial organization characteristics of traditional cave dwelling villages in northern Shaanxi Province.The extracted climate adaptability principles are summarized,and the resulting design strategies that are well-suited to the contemporary urban space form are presented.Through analysis,it can be observed that traditional cave dwelling villages in northern Shaanxi are predominantly situated on south-facing slopes in proximity to water at low altitudes.These villages are characterized by compact building groups and east-west development,which is constrained by the elements of mountains and rivers.A two-level street system is generated,comprising streets parallel to the contour line and roadways perpendicular to the contour line.This results in the formation of a courtyard form enclosed by mountains.Such site layout and spatial organization exhibit excellent climate adaptability with regard to heat,ventilation,and wind storage.In light of the aforementioned considerations,the following urban spatial form design strategies are put forth:①the topographic height difference can be exploited to obtain sufficient sunshine;②the group shape can be optimized in order to reduce building energy consumption;③the best orientation of the building can be chosen to take account of both winter and summer conditions;④the height and length can be combined in order to form natural masking;⑤the D/H ratio of streets and roadways should be controlled to achieve a balance between heat gain and cooling of groups;⑥vents should be set appropriately to optimize group ventilation;⑦climate buffers should be established to increase the level of climate response. 展开更多
关键词 Traditional cave dwellings in northern Shaanxi Urban spatial form Outdoor thermal environment
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Well water contaminants and colorectal cancer in North Dakota
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作者 Amber D Lyon-Colbert Marc D Basson +1 位作者 Marilyn G Klug Gary G Schwartz 《World Journal of Clinical Oncology》 2024年第11期1454-1458,共5页
This study aims to identify common contaminants in well water linked to an increase in colorectal cancer(CRC)incidence rates in North Dakota(ND)counties.County-specific incidence rates for CRC were obtained from the N... This study aims to identify common contaminants in well water linked to an increase in colorectal cancer(CRC)incidence rates in North Dakota(ND)counties.County-specific incidence rates for CRC were obtained from the ND Statewide Cancer Registry.Corresponding demographic,agricultural,and geophysical data were obtained from population-based sources.Associations between well water contaminants and CRC incidence were examined for 16 counties in ND with complete well water profiles between 1997-2019.Data were analyzed by multiple linear regression.Iron in well water exhibited a significant positive association with CRC incidence(4.75,P=0.001),and barium exhibited a small,but significant negative association(-0.06907,P=0.01).Residents in counties in ND with prevalent well water usage contaminated with iron may be at higher risk for CRC. 展开更多
关键词 Colorectal cancer IRON Water quality Well water North Dakota
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Assessment of Municipal Solid Waste Management in the Farmgate Area of Dhaka North City Corporation
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作者 Seyedali Mirmotalebi Shoeb Rahman +1 位作者 Mayida Rubya Tithi Imran Khan Apu 《World Journal of Engineering and Technology》 2024年第1期1-23,共23页
This investigation is focused on conducting a thorough analysis of Municipal Solid Waste Management (MSWM). MSWM encompasses a range of interdisciplinary measures that govern the various stages involved in managing un... This investigation is focused on conducting a thorough analysis of Municipal Solid Waste Management (MSWM). MSWM encompasses a range of interdisciplinary measures that govern the various stages involved in managing unwanted or non-utilizable solid materials, commonly known as rubbish, trash, junk, refuse, and garbage. These stages include generation, storage, collection, recycling, transportation, handling, disposal, and monitoring. The waste materials mentioned in this context exhibit a wide range of items, such as organic waste from food and vegetables, paper, plastic, polyethylene, iron, tin cans, deceased animals, byproducts from demolition activities, manure, and various other discarded materials. This study aims to provide insights into the possibilities of enhancing solid waste management in the Farmgate area of Dhaka North City Corporation (DNCC). To accomplish this objective, the research examines the conventional waste management methods employed in this area. It conducts extensive field surveys, collecting valuable data through interviews with local residents and key individuals involved in waste management, such as waste collectors, dealers, intermediate dealers, recyclers, and shopkeepers. The results indicate that significant amounts of distinct waste categories are produced daily. These include food and vegetable waste, which amount to 52.1 tons/day;polythene and plastic, which total 4.5 tons/day;metal and tin-can waste, which amounts to 1.4 tons/day;and paper waste, which totals 5.9 tons/day. This study highlights the significance of promoting environmental consciousness to effectively shape the attitudes of urban residents toward waste disposal and management. It emphasizes the need for collaboration between authorities and researchers to improve the current waste management system. 展开更多
关键词 Solid Waste Management Dhaka North City Corporation Sustainable Growth Integrated Waste Management Practice Waste Recycling
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Land use effects on the dynamics of soil C,N and microbes in the water-wind erosion crisscross region of the northern Loess Plateau,China 被引量:1
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作者 Yi WANG Chunyue LI Shunjin HU 《Pedosphere》 SCIE CAS CSCD 2024年第1期181-190,共10页
The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable l... The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify suitable land use types that can maintain soil fertility and sustainability. A field experiment was performed in Liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainfed slope land, deciduous broadleaf forest, evergreen coniferous forest, shrubland, and grassland,were measured in three different growing seasons. Land use type and season significantly affected TOC, TN, and the dynamics of microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern for TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend after natural grassland was converted to shrubland,forest, and rainfed slope land. Shrubland with exotic N-fixing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes for soil microbial biomass and activity and explained 88.90% of the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of the northern Loess Plateau to maintain ecosystem stability and sustainability. 展开更多
关键词 GRASSLAND microbial activity microbial biomass total organic C total N WATERSHED
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Mechanism underlying the uprooting of taproot-type shrub species in the loess area of northeastern Qinghai-Xizang Plateau, China
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作者 LIANG Shen WANG Shu +4 位作者 LIU Yabin PANG Jinghao ZHU Haili LI Guorong HU Xiasong 《Journal of Arid Land》 SCIE CSCD 2024年第10期1426-1443,共18页
Characteristics of root pullout resistance determine the capacity to withstand uprooting and the slope protection ability of plants.However,mechanism underlying the uprooting of taproot-type shrub species in the loess... Characteristics of root pullout resistance determine the capacity to withstand uprooting and the slope protection ability of plants.However,mechanism underlying the uprooting of taproot-type shrub species in the loess area of northeastern Qinghai-Xizang Plateau,China remains unclear.In this study,a common taproot-type shrub,Caragana korshinskii Kom.,in northeastern Qinghai-Xizang Plateau was selected as the research material.Mechanism of root-soil interaction of vertical root of C.korshinskii was investigated via a combination of a single-root pullout test and numerical simulation analysis.The results indicated that,when pulling vertically,axial force of the roots decreased with an increase in buried depth,whereas shear stress at root-soil interface initially increased and then decreased as burial depths increased.At the same buried depth,both axial force and shear stress of the roots increased with the increase in pullout force.Shear stress and plastic zone of the soil surrounding the root were symmetrically distributed along the root system.Plastic zone was located close to the surface and was caused primarily by tensile failure.In nonvertical pulling,symmetry of shear stress and plastic zone of the soil surrounding the root was disrupted.We observed larger shear stress and plastic zones on the side facing the direction of root deflection.Plastic zone included both shear and tensile failure.Axial force of the root system near the surface decreased as deflection angle of the pullout force increased.When different rainfall infiltration depths had the same vertical pulling force,root axial force decreased with the increase of rainfall infiltration depth and total root displacement increased.During rainfall infiltration,shear stress and plastic zone of the soil surrounding the root were prone to propagating deeper into the soil.These findings provide a foundation for further investigation of soil reinforcement and slope protection mechanisms of taproot-type shrub species in the loess area of northeastern Qinghai-Xizang Plateau and similar areas. 展开更多
关键词 Qinghai-Xizang Plateau shrub roots pullout test numerical simulation MECHANISM root-soil interaction
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Exploring the Path of Shantytown Renewal Based on the Theory of Environment-behavior Studies: A Case Study of the Northwest Area of Saihantala in Baotou City
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作者 ZHANG Miao TIAN Jiaqi GONG Rui 《Journal of Landscape Research》 2024年第2期61-65,68,共6页
The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environme... The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environment from the perspective of human daily behavior.Most of the shantytown renovation projects currently carried out in China are mainly focused on demolition and reconstruction,which not only incurs high costs but also damages the original social structure and economic model.During the process of shantytown renewal,it should improve the urban landscape,living environment,and life quality of residents,and ensure the daily life of shantytown residents without increasing their economic burden,and preserve the traces of urban development.In order to achieve this goal,it should explore the renewal strategies of shantytowns from the perspective of environment-behavior studies through behavior maps,on-site research,and literature review.Updating and design from a human perspective often achieve faster and better development;the renewal of shantytowns should be a bottom-up approach and start from a grassroots perspective,completing the renovation design through the composition of the population and behavioral patterns. 展开更多
关键词 Environment-behavior studies Shantytown renewal Economic type Bottom view BOTTOM-UP
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Design of Barrier-free Evacuation for Diverse Crowd on Campus Based on Evacuation Simulation: A Case Study of North China University of Technology
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作者 ZHANG Zonghui SONG Rui +1 位作者 AN Zeyi ZHAO Xingmin 《Journal of Landscape Research》 2024年第5期19-26,共8页
By using evacuation simulation technology and taking North China University of Technology as an example,the barrier-free evacuation design scheme for groups with different needs in campus environment was deeply discus... By using evacuation simulation technology and taking North China University of Technology as an example,the barrier-free evacuation design scheme for groups with different needs in campus environment was deeply discussed.Based on the data of building layout,population composition,road system and distribution of shelters in the school,a detailed evacuation model was constructed in the Pathfinder emergency evacuation simulation system.By the simulation during the daytime and at night,the total evacuation time of the whole school,evacuation completion time of each building,selection of evacuation paths and shelter utilization were analyzed in detail.The simulation results show that the distribution of shelters on campus is uneven,and their capacity is limited.As a result,the evacuation paths of the disabled,the elderly and children need to be adjusted frequently,which affects the overall evacuation efficiency.In view of this,the optimization strategies of road renovation and entrances of shelters and buildings were put forward from the perspective of space planning.From the perspective of emergency management,it is suggested to improve the campus evacuation infrastructure and strengthen the evacuation drill for teachers and students.These results provide a solid theoretical support for enhancing the construction of campus barrier-free environment and improving the level of emergency management. 展开更多
关键词 Diverse crowd Campus barrier-free evacuation design Analogue simulation SHELTER
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Sedimentary Expressions of the Early Jurassic Jenkyns Event in an Inland Lacustrine System in the Yin'gen-Ejinaqi Basin,North China
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作者 YANG Bing XU Guozhen +5 位作者 HUI Guangji WEI Yi ZHANG Xinzhi YI Jinjun SUN Siyuan ZHANG Sujiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1359-1375,共17页
The Jenkyns Event,more widely known as the Toarcian Oceanic Anoxic Event(T-OAE),is marked by globally distributed negative carbon-isotope excursions,widespread oxygen depletion,and large-scale organic carbon burial,wh... The Jenkyns Event,more widely known as the Toarcian Oceanic Anoxic Event(T-OAE),is marked by globally distributed negative carbon-isotope excursions,widespread oxygen depletion,and large-scale organic carbon burial,which indicate major climate/environmental perturbations in Earth's surface systems during the Early Jurassic.Although extensive research has been conducted in European continental settings,particularly in the western peri-Tethys regions,the impacts of this event beyond Europe remains largely unexplored.Here,a multiapproach study including investigations into the sporepollen assemblages,pyrite framboids,clay minerals,total organic carbon(TOC)levels,and organic carbon isotope(δ13Corg)levels in a lacustrine borehole section(MED1)from the Yin'gen-Ejinaqi Basin,North China,provides evidence of the occurrence of the Jenkyns Event and its extensive sedimentary responses in the eastern Tethys terrestrial systems.Two distinct spore-pollen assemblages have been identified in MED1(drilling depth:982.4 m to 1267.5 m),with the Cycadopites-Protopinus-Osmundacidites assemblage in the lower part(1267.5 m to 1132.9 m)indicating a middle Early Jurassic age and the Classopollis assemblage in the upper part(1132.9 m to 985.7 m)suggesting a Toarcian age.Framboidal pyrite data suggest more anoxic conditions during the deposition of black mudstone and shale intercalations in the lower part of the Classopollis assemblage(1132.9 m to 1066.9 m),which combined with organic carbon enrichment and negativeδ13Corg excursions,are considered the paleoenvironmental response to the Jenkyns Event in the study area.Furthermore,the evolution of vegetation groups changed from plant groups characterized by bisaccate and cycad pollen,as well as fern spores,to vegetation groups represented by Cheirolepidiaceae pollen across the Jenkyns Event,as evidenced by sporepollen data,together with the clay mineral assemblage change characterized by a notable increase in illite at the expense of kaolinite,suggests that while a subtropical-temperate climate persisted,a change toward warmer and drier conditions most likely occurred in the early Toarcian in the study area.In contrast to the humidification evidenced in many coastal settings,this aridification trend in the Yin'gen-Ejinaqi Basin aligns with the conditions in many inland areas.It is hypothesized that the underlying cause of these divergent changes may be linked to certain patterns of spatially variable water availability on land,potentially driven by extremified hydrological conditions. 展开更多
关键词 spore-pollen assemblages clay minerals pyrite framboids organic carbon isotope Jenkyns event
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Molecular Epidemiology and Clinical Characteristics of Hand, Foot and Mouth Disease in North Sichuan Region, China, 2018-2023: A Descriptive Study
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作者 Zhe Xu Zheng Zhao +6 位作者 Linming Fan Manyu Liang Jinglu Chen Jia Zeng Ping Shi Xi’en Gu Zhengdong Li 《Advances in Microbiology》 CAS 2024年第6期317-332,共16页
Background: Hand, foot and mouth disease (HFMD) remains an important public health problem in China. Many studies on the epidemiological characteristics of HFMD have been reported, but studies in North Sichuan region ... Background: Hand, foot and mouth disease (HFMD) remains an important public health problem in China. Many studies on the epidemiological characteristics of HFMD have been reported, but studies in North Sichuan region have been neglected. Methods: HFMD-related enterovirus infected cases were clinically confirmed and underwent real-time RT-PCR (rRT-PCR) from May 2018 to October 2023 in Guangyuan Central Hospital. Results: During 2018-2023, other EV (437 cases, 81.08%) was the most predominant serotype followed by CV-A16 (94 cases, 17.44%), EV-A71 (8 cases, 1.48%) was the least predominant serotype. Peak infections occurred in July and October. There were no significant differences in gender, age and serotypes. HFMD was concentrated in children under 47 months of age, with the highest incidence in children aged 12 - 23 months and the highest proportion of other EV infections in the whole age group. COVID-19 did not cause significant changes in gender, age and serotype. Overall, there was a significant increase in the proportion of children aged 12 - 23 months infected with CV-A16, and an increase in the proportion of children aged over 36 months infected with other EVs. Conclusions: The incidence of HFMD caused by EV-A71 has decreased significantly, and other EVs have become the main pathogens of HFMD in North Sichuan region in recent years. In the prevention and control of CV-A16, more attention should be paid to children aged 12 - 23 months and the dominant serotype should be closely monitored. Our study highlights the importance of developing of new diagnostic reagents and vaccines for the prevention and control of enterovirus infection. This study for the first time provides insights into district interventions to local conditions. 展开更多
关键词 ENTEROVIRUS HFMD EPIDEMIOLOGY Clinical Characteristics
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Petrogenesis and tectonic implications of the Silurian adakitic granitoids in the eastern segment of the Qilian Orogenic Belt,Northwest China
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作者 Jiao-Long Zhao Xiao-Jun Huang +5 位作者 Pei-Qing Hu Zhen-Xi Yang Ying Fan Er-Teng Wang Fu-Bo Yang Jing-Yu Zhang 《Acta Geochimica》 EI CAS CSCD 2024年第1期72-86,共15页
Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon U–Pb age, and sy... Geodynamic mechanism responsible for the generation of Silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon U–Pb age, and systematic whole-rock geochemical data for the Haoquangou and Liujiaxia granitoids within the North Qilian orogenic belt and the Qilian Block, respectively, to constrain their petrogenesis, and the Silurian tectonic evolution of the Qilian orogenic belt. Zircon U–Pb ages indicate that the Haoquangou and Liujiaxia intrusions were emplaced at423 ± 3 Ma and 432 ± 4 Ma, respectively. The Haoquangou granodiorites are calc-alkaline, while the Liujiaxia granites belong to the high-K calc-alkaline series.Both are peraluminous in composition and have relatively depleted Nd isotopic [ε_(Nd)(t) =(-3.9 – + 0.6)] characteristics compared with regional basement rocks, implying their derivation from a juvenile lower crust. They show adakitic geochemical characteristics and were generated by partial melting of thickened lower continental crust. Postcollisional extensional regime related to lithospheric delamination was the most likely geodynamic mechanism for the generation of the Haoquangou granodiorite, while the Liujiaxia granites were generated in a compressive setting during continental collision between the Qaidam and Qilian blocks. 展开更多
关键词 Silurian adakitic granitoids PETROGENESIS Tectonic setting Qilian Orogenic Belt
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Structural Evolution and Hydrocarbon Potential of the Upper Paleozoic Northern Ordos Basin, North China 被引量:9
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作者 YANG Minghui LI Liang +4 位作者 ZHOU Jin JIA Huichong SUN Xiao GONG Ting DING Chao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第5期1636-1648,共13页
The hydrocarbon potential of the Hangjinqi area in the northern Ordos Basin is not well known, compared to the other areas of the basin, despite its substantial petroleum system.Restoration of a depth-converted seismi... The hydrocarbon potential of the Hangjinqi area in the northern Ordos Basin is not well known, compared to the other areas of the basin, despite its substantial petroleum system.Restoration of a depth-converted seismic profile across the Hangjinqi Fault Zone(HFZ) in the eastern Hangjinqi area shows one compression that created anticlinal structures in the Late Triassic, and two extensions in ~Middle Jurassic and Late Early Cretaceous, which were interrupted by inversions in the Late Jurassic–Early Early Cretaceous and Late Cretaceous, respectively.Hydrocarbon generation at the well locations in the Central Ordos Basin(COB) began in the Late Triassic.Basin modeling of Well Zhao-4 suggests that hydrocarbon generation from the Late Carboniferous–Early Permian coal measures of the northern Shanbei Slope peaked in the Early Cretaceous, predating the inversion in the Late Cretaceous.Most source rocks in the Shanbei Slope passed the main gas-migration phase except for the Hangjinqi area source rocks(Well Jin-48).Hydrocarbons generated from the COB are likely to have migrated northward toward the anticlinal structures and traps along the HFZ because the basin-fill strata are dipping south.Faulting that continued during the extensional phase(Late Early Cretaceous) of the Hangjinqi area probably acted as conduits for the migration of hydrocarbons.Thus, the anticlinal structures and associated traps to the north of the HFZ might have trapped hydrocarbons that were charged from the Late Carboniferous–Early Permian coal measures in the COB since the Middle Jurassic. 展开更多
关键词 structural geology hydrocarbons Upper Paleozoic Hangjinqi northern Ordos Basin North China
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Coal mining in northeast India: an overview of environmental issues and treatment approaches 被引量:17
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作者 Mayuri Chabukdhara O. P. Singh 《International Journal of Coal Science & Technology》 EI 2016年第2期87-96,共10页
Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash cont... Northeast India has a good deposit of sub-bituminous tertiary coal. The northeast Indian coals have unusual physico-chemical characteristics such as high sulfur, volatile matter and vitrinite content, and low ash content. In addition, many environmental sensitive organic and mineral bound elements such as Fe, Mg, Bi, AI, V, Cu, Cd, Ni, Pb, and Mn etc. remain enriched in these coals. Such characteristics are associated with more severe environmental impacts due to mining and its utilization in coal based industries. Environmental challenges include large scale landscape damage, soil erosion, loss of forest ecosystem and wildlife habitat, air, water and soil pollution. Several physical and chemical methods are reported in literature for the removal of mineral matter, total sulfur and different forms of sulfur from high sulfur coal in northeast India. This paper may help different researchers and stakeholders to understand current state of research in the field. Initiatives may be taken towards sustainable use of coal resources by adopting innovative clean technologies and by implementing effective control measures and regulatory policies. 展开更多
关键词 Northeast India Sub-bituminous coal Environmental issues Innovative technologies Management andregulatory policies
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Cenozoic tectono-sedimentary characteristics and extension model of the Northwest Sub-basin,South China Sea 被引量:8
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作者 Weiwei Ding Mingbi Li +2 位作者 Lihong Zhao Aiguo Ruan Zhenli Wu 《Geoscience Frontiers》 SCIE CAS 2011年第4期509-517,共9页
Based on the interpretations of three seismic profiles and one wide-angle seismic profile across the Northwest Sub-basin,South China Sea.stratigraphic sequences,deformation characteristics and an extension model for t... Based on the interpretations of three seismic profiles and one wide-angle seismic profile across the Northwest Sub-basin,South China Sea.stratigraphic sequences,deformation characteristics and an extension model for this sub-basin have been worked out.Three tectonic-stratigraphic units are determined.Detailed analyses of extension show that the event occurred mainly during the Paleogene and resulted in the formation of half-grabens or grabens distributed symmetrically around the spreading center.Sediments are characterized by chaotic and discontinuous reflectors,indicating clastic sediments. Farther to the southwest,the sub-basin features mainly continental rifting instead of sea-floor spreading. The rifting would have been controlled by the shape of the massif and developed just along the northern edge of the Zhongsha-Xisha Block,rather than joined the Xisha Trough.After 25 Ma.a southward ridge jump triggered the opening of the Southwest Sub-basin.The NW-directed stress caused by the sea-floor spreading of the Northwest Sub-basin may have prevented the continuous opening of the sub-basin.After that the Northwest Sub-basin experienced thermal cooling and exhibited broad subsidence.The deep crustal structure shown by the velocity model from a wide-angle seismic profile is also symmetrical around the spreading center,which indicates that the Northwest Sub-basin might have opened in a pure shear model. 展开更多
关键词 Continental rifting CENOZOIC Tectono-sedimentary characteristics Extension model Northwest Sub-basin Marginal sea
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Evolution of the Madrean-Tethyan disjunctions and the North and South American amphitropical disjunctions in plants 被引量:14
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作者 Jun WEN Stefanie M. ICKERT-BOND 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第5期331-348,共18页
The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- T... The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns: (i) between Eurasian and western North American deserts with the Mediterranean climate (the Madrean- Tethyan disjunctions); and (ii) between the temperate regions of North and South America (the amphitropical disjunctions). Both disjunct patterns have multiple times of origin. The amphitropical disjunctions have largely resulted from long-distance dispersal, primarily from the Miocene to the Holocene, with available data indicating that most lineages dispersed from North to South America. Results of recent studies on the Mediterranean disjuncts between the deserts of Eurasia and western North America support the multiple modes of origin and are mostly consistent with hypotheses of long-distance dispersal and the North Atlantic migration. Axelrod's Madrean-Tethyan hypothesis, which implies vicariance between the two regions in the early Tertiary, has been favored by a few studies. The Beringian migration corridor for semiarid taxa is also supported in some cases. 展开更多
关键词 amphitropical disjunctions BIOGEOGRAPHY Madrean-Tethyan disjunctions Mediterranean disjuncts North-South American disjunctions.
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Mutual optimization of water utilization structure and industrial structure in arid inland river basins of Northwest China 被引量:14
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作者 BAO Chao FANG Chuanglin CHEN Fan 《Journal of Geographical Sciences》 SCIE CSCD 2006年第1期87-98,共12页
Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the... Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins. 展开更多
关键词 water utilization structure industrial structure mutual optimization System Dynamic Model arid inland river basins Northwest China
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