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Research status and hotspots of tight junctions and colorectal cancer:A bibliometric and visualization analysis
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作者 Hui-Min Li Yin Liu +5 位作者 Meng-Di Hao Xiao-Qing Liang Da-Jin Yuan Wen-Bin Huang Wen-Jie Li Lei Ding 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3705-3715,共11页
BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding... BACKGROUND Colorectal cancer(CRC)is the third most common cancer worldwide and the second leading cause of cancer-related death.Over the past two decades,numerous researchers have provided important evidence regarding the role of tight junction(TJ)proteins in the occurrence and progression of CRC.The causal relationship between the presence of specific TJ proteins and the development of CRC has also been confirmed.Despite the large number of publications in this field,a bibliometric study to review the current state of research and highlight the research trends and hotspots in this field has not yet been performed.AIM To analyze research on TJs and CRC,summarize the field’s history and current status,and predict future research directions.METHODS We searched the Science Citation Index Expanded database for all literature on CRC and TJs from 2001-2023.We used bibliometrics to analyze the data of these papers,such as the authors,countries,institutions,and references.Co-authorship,co-citation,and co-occurrence analyses were the main methods of analysis.CiteSpace and VOSviewer were used to visualize the results.RESULTS A total of 205 studies were ultimately identified.The number of publications on this topic has steadily increased since 2007.China and the United States have made the largest contributions to this field.Anticancer Research was the most prolific journal,publishing 8 articles,while the journal Oncogene had the highest average citation rate(68.33).Professor Dhawan P was the most prolific and cited author in this field.Co-occurrence analysis of keywords revealed that“tight junction protein expression”,“colorectal cancer”,“intestinal microbiota”,and“inflammatory bowel disease”had the highest frequency of occurrence,revealing the research hotspots and trends in this field.CONCLUSION This bibliometric analysis evaluated the scope and trends of TJ proteins in CRC,providing valuable research perspectives and future directions for studying the connection between the two.It is recommended to focus on emerging research hotspots,such as the correlations among intestinal microbiota,inflammatory bowel disease,TJ protein expression,and CRC. 展开更多
关键词 Colorectal cancer Tight junctions Bibliometric analysis Research trends Hot spots
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics Controlling factors Shale oil Sweet spot
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Key geological factors governing sweet spots in the Wufeng-Longmaxi shales of the Sichuan Basin,China
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作者 Zongquan Hu Zengqin Liu +4 位作者 Wei Du Zhenrui Bai Ruyue Wang Chuanxiang Sun Dongjun Feng 《Energy Geoscience》 EI 2024年第3期163-174,共12页
Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characterist... Production performance of the Wufeng-Longmaxi shales varies significantly among Fuling,Weirong,and Wulong fields in the Sichuan Basin.Total organic carbon(TOC)content,mineralogy,and organic matter(OM)pore characteristics are investigated to identify key factors governing sweet spots.Siliceous shales with good preservation conditions in the Fuling Field exhibit large thickness,high TOC content and thin-section porosity(TSP),and well-developed OM macropores,thus high initial production and estimated ultimate recovery(EUR).Thin carbonate-containing siliceous shales with good preservation conditions in the Weirong Field feature medium-to-high TOC and well-developed OM macropores but low TSP,leading to high initial production but low EUR.Siliceous shales with poor preservation conditions in the Wulong Field are characterized by large thickness,high TOC,low TSP and poorly-developed OM macropores,causing low initial production and EUR.Both sedimentary and preservation conditions are intrinsic decisive factors of sweet spots,as they control the mineral composition,TOC,and OM macropore development.Deep-water shales in transgressive systems tracts(TSTs)exhibit better-developed OM macropores and greater TOC compared to highstand systems tracts(HSTs).OM macropores are most prevalent in siliceous shales,followed by carbonate-containing siliceous shales and then argillaceous shales.Furthermore,good preservation conditions are conducive to retain OM macropores with low pore aspect ratio(PAR).Comparison among the three fields shows that high-TOC silicious shales with good preservation conditions are the highest in TSP and EUR.Therefore,organic richness,lithofacies,and preservation conditions are the major factors which determine OM pore development,governing the sweet spots of the Wufeng-Longmaxi shales. 展开更多
关键词 Shale gas Organic matter pores Sweet spot Wufeng-Longmaxi shales Sichuan basin
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An insight on the mechanism of efficient leaching of vanadium from vanadium shale induced by microwave-generated hot spots 被引量:3
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作者 Sheng Li Yimin Zhang +1 位作者 Yizhong Yuan Pengcheng Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期293-302,共10页
Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscop... Microwave heating can rapidly and uniformly raise the temperature and accelerate the reaction rate.In this paper,microwave heating was used to improve the acid leaching,and the mechanism was investigated via microscopic morphology analysis and numerical simulation by COMSOL Multiphysics software.The effects of the microwave power,leaching temperature,CaF_(2) dosage,H_(2)SO_(4) concentration,and leaching time on the vanadium recovery were investigated.A vanadium recovery of 80.66%is obtained at a microwave power of 550 W,leaching temperature of 95℃,CaF_(2) dosage of 5wt%,H_(2)SO_(4) concentration of 20vol%,and leaching time of 2.5 h.Compared with conventional leaching technology,the vanadium recovery increases by 6.18%,and the leaching time shortens by 79.17%.More obvious pulverization of shale particles and delamination of mica minerals happen in the microwave-assisted leaching process.Numerical simulation results show that the temperature of vanadium shales increases with an increase in electric field(E-field).The distributions of E-field and temperature among vanadium shale particles are relatively uniform,except for the higher content at the contact position of the particles.The analysis results of scaleup experiments and leaching experiments indicate high-temperature hot spots in the process of microwave-assisted leaching,and the local high temperature destroys the mineral structure and accelerates the reaction rate. 展开更多
关键词 vanadium shale microwave-assisted leaching hot spots numerical simulation
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The effect of activating fluxes on the cathode spots in the activating TIG welding 被引量:1
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作者 黄勇 王伯洋 +4 位作者 郭建航 刘永刚 黄健康 樊丁 余淑荣 《China Welding》 CAS 2023年第1期7-17,共11页
The cathode spots are a common phenomenon in the TIG(tungsten inert gas)welding process.However,it is rarely observed in the activating TIG welding process.This research is mainly focused on the effect of activating f... The cathode spots are a common phenomenon in the TIG(tungsten inert gas)welding process.However,it is rarely observed in the activating TIG welding process.This research is mainly focused on the effect of activating flux on cathode spots in the activating TIG welding.The characteristics and behaviors of cathode spots were investigated in activating TIG welding by the high-speed camera and the spectrograph.Three kinds of oxide(TiO_(2),SiO_(2),MnO_(2))and two halide(MnCl_(2),CaF_(2))activating fluxes are used in the activating TIG welding process.The results show that differ from the TIG welding,the oxide activating flux increases the number of cathode spots and decreases the velocity.The effect is the opposite for the halide activating flux.Moreover,the number of spots no longer varies with the current except TiO2 activating flux.As the temperature of the weld pool surface increases the spot moves away from the center.But this rule is not valid when silica and manganese compounds activating fluxes are used.The variation of cathode spots is caused by the oxide film reformed and the distribution of weld slag.The formation mechanism of cathode spots might be the impact of ions on the cathode surface and the strong electric field formed near the cathode surface. 展开更多
关键词 cathode spots behaviors activating tungsten inert gas welding high-speed photography spectrum
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Developing Blue Spots Model for Tennessee Using GIS, and Advanced Data Analytics: Literature Review
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作者 Fasesin Kingsley 《Journal of Geoscience and Environment Protection》 2023年第6期145-154,共10页
Climate change and global warming results in natural hazards, including flash floods. Flash floods can create blue spots;areas where transport networks (roads, tunnels, bridges, passageways) and other engineering stru... Climate change and global warming results in natural hazards, including flash floods. Flash floods can create blue spots;areas where transport networks (roads, tunnels, bridges, passageways) and other engineering structures within them are at flood risk. The economic and social impact of flooding revealed that the damage caused by flash floods leading to blue spots is very high in terms of dollar amount and direct impacts on people’s lives. The impact of flooding within blue spots is either infrastructural or social, affecting lives and properties. Currently, more than 16.1 million properties in the U.S are vulnerable to flooding, and this is projected to increase by 3.2% within the next 30 years. Some models have been developed for flood risks analysis and management including some hydrological models, algorithms and machine learning and geospatial models. The models and methods reviewed are based on location data collection, statistical analysis and computation, and visualization (mapping). This research aims to create blue spots model for the State of Tennessee using ArcGIS visual programming language (model) and data analytics pipeline. 展开更多
关键词 Blue spots Floods Risks and Management GIS Hydrological Models GEOSPATIAL Model Builder LiDAR Data Remote Sensing Data Analytics Pipe-line
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Storage of Gamma-Glutamyltransferase from Dried Serum Spots: Matrix for Field Based Studies
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作者 Ram Kumar Rizwana Quraishi 《Pharmacology & Pharmacy》 2023年第11期478-481,共4页
Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This stud... Background: Gamma-glutamyltransferase is recognised as a biomarker to assess the harms associated with alcohol misuse. The objective ways to measure GGT in areas lacking central lab facilities are desirable. This study aims to measure GGT from dried serum spots and its storage from dried serum spots. Method: The study was approved by the institutional ethical committee. One hundred and eighty (180) patients were included in the study. Their blood samples were collected. The serum samples were spotted onto filter paper (Whatman 903) dried and stored at 4°C. The GGT levels were measured on the day of collection and at various time periods to assess the effect of storage. All the analysis was performed on SPSS version 21. Result: The GGT levels measured from fresh serum GGT levels mean (SD) 286.5 (539.4) correlated well with their respective dried serum levels 287.18 (538.2) (P = 0.80). The mean recovery of GGT from dried serum was observed to be 103.3%. A sub-sample (n = 12) was stored at 4°C. The dried serum spots were found to be stable at the end of four weeks using repeated measure analysis of variance (ANOVA) (P = 0.39). Conclusion: This method has the potential to be used for epidemiological or field based studies to assess harms associated with alcohol use. 展开更多
关键词 STORAGE GAMMA-GLUTAMYLTRANSFERASE Dried Serum spots
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Investigating the tourism image of mountain scenic spots in China through the lens of tourist perception 被引量:2
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作者 LI Feng-jiao LIAO Xia +3 位作者 LIU Jia-ming JIANG Li-li WANG Meng-di LIU Jin-feng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2298-2314,共17页
A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emot... A favorable tourism image of high-quality mountain scenic spots(HQMSS)is crucial for tourism prosperity and sustainability.This paper establishes a framework for investigating the tourism image based on cognitive-emotion theory and uses natural language processing(NLP)tools to clarify the cognition,emotion,and overall tourist image of the HQMSS in China from the perspective of tourist perception.This paper examines the multi-dimensional spatial differentiation of China's overall image,including province,scenic spot scales,as well as the spatial pattern of the overall comprehensive tourism image.Strategies for comprehensively improving HQMSS's tourism image are also formulated.The results show that:(1)The cognitive image of Chinese HQMSS is categorized into core and marginal images,and the core images such as scenery and cable car are the expression of the uniqueness of mountainous scenic spots.Additionally,the cognitive image is classified into six dimensions:tourism environment,tourism supporting facilities,tourism experience,tourism price,tourism service,and tourism safety.(2)Positive emotions are the dominant mood type of HQMSS in China,followed by neutral emotions,with negative emotions being the least frequent.Emotional images vary across dimensions,with tourism environment and tourism experience evoking relatively higher emotion.(3)The spatial pattern of HQMSS for each dimension at the national,provincial,and scenic scales is diversifying.This article provides a multidimensional perspective for investigating the tourism image of mountainous scenic spots,proposes targeted recommendations to improve the overall image of HQMSS in China,and can greatly contribute to the sustainable development of mountain tourism. 展开更多
关键词 Mountain scenic spot Tourism image Spatial differentiation Natural language processing Cognitive-emotion theory Tourist perception
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The Sunspots
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作者 Angel Fierros Palacios 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第2期72-87,共16页
In the present paper, the theoretical frame work of magneto hydrodynamics (MHD) is used to give a solution of the problem about the origin, persistence and disappearance of the Sunspots;as well as their tendency to ap... In the present paper, the theoretical frame work of magneto hydrodynamics (MHD) is used to give a solution of the problem about the origin, persistence and disappearance of the Sunspots;as well as their tendency to appear as bipolar magnetic couples. According to the results obtained, a possible explanation about the change of polarity in both solar hemispheres is given. Heuristic but logical arguments about the periodicity of the phenomenon of the observed magnetic polarity and the tendency of couples of Sunspots to appear solely in certain latitudes that can be called tropical regions of the Sun are presented. Finally, an indirect experimental test is proposed to show the possible process that produces the polarity of the Sunspots in a given cycle, as well as the invertion of that polarity in the next solar cycle. 展开更多
关键词 MAGNETIC Field of the spots Sunspots Theory MAGNETIC Regulation of Thermal CONVECTION Polarity of the SUNspots Couples Solar CYCLE Structure and Stability of the spots Life Time of the spots
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The Spatial Patterns of Road Traffic Crash Black Spots and Emergency Facilities in Federal Capital City
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作者 Mamman Saba Jibril David Sesugh Aule Badiatu Danladi Garba 《Journal of Geoscience and Environment Protection》 2023年第2期121-134,共14页
This study aimed at determining the spatial patterns of Road Traffic Crash (RTC) black spots, Federal Road Safety Commission (FRSC) zebra points and emergency health care facilities in Federal Capital City (FCC). The ... This study aimed at determining the spatial patterns of Road Traffic Crash (RTC) black spots, Federal Road Safety Commission (FRSC) zebra points and emergency health care facilities in Federal Capital City (FCC). The aim was to provide stakeholders with information that will aid their understanding of accident prone locations and accessible rescue possibilities for accident victims on the roads in FCT. GPS Map 76S Mark (GARMIN) was used to locate and pick coordinates of data in the study area. A total of 16 possible emergency health care facilities, seventy (70) RTC black spots and Five Zebra point locations were obtained from FRSC. ArcGIS 10.0 was used to compute the data by plotting the coordinates to produce maps of the spatial relationship and to carry out Nearest Neighbour Analysis (NNA). The result was further used to determine the spatial patterns of RTC black spots as well as patterns of the emergency facilities. Generally, the result shows that the spatial trend is turning towards dispersion. However, there is less than 1% likelihood that the dispersed patterns could be the result of random chance. It was recommended that, the Federal Road Safety Commission should be staffed with trained professionals that can be responsible for accident data surveillance and analysis using geospatial techniques. 展开更多
关键词 ACCIDENT Black Spot EMERGENCY Pattern Spatial Zebra Point
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Quantitative and Comprehensive Prediction of Shale Oil Sweet Spots in Qingshankou Formation, Songliao Basin
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作者 Tiantian Wu Xin Bai +9 位作者 Fei Shang Haiyan Zhou Lan Wang Xuexian Zhou Zhi Zhong Zhi Yang Jinyou Zhang Xinyang Cheng Peiyu Zhang Ruiqian Chen 《Journal of Geoscience and Environment Protection》 2023年第5期290-315,共26页
The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”.... The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”. To accurately identify and optimize the favorable sweet spots of shale oil in Qingshankou Formation, Songliao Basin, the original logging data were preprocessed in this paper. Then the thin mud shale interlayer of Qingshankou Formation was identified effectively by using the processed logging data. Based on the artificial neural network method, the mineral content of mud shale in Qingshankou Formation was predicted. The lithofacies were identified according to the mineral and TOC content. Finally, a three-dimensional (3-D) model of total organic carbon (TOC), vitrinite reflectance (Ro), mineral content, and rock of Qingshankou Formation in Songliao Basin was established to evaluate and predict the favorable sweet spots of shale oil in the study area. The results show that there are a lot of calcareous and siliceous thin interlayers in Qingshankou Formation, and TOC content is generally between 2% and 3%. Ro is the highest in Gulong sag, followed by Sanzhao sag. The lithofacies mainly consists of felsic shale and mixed shale, mainly in the first member of Qingshankou Formation. Comprehensive analysis shows that shale oil development potential is enormous in the eastern part of Sanzhao Sag and the northern part of Gulong Sag. 展开更多
关键词 Songliao Basin Qingshankou Formation Shale Oil Sweet Spot Artificial Neural Network
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Research Progress and Prospect of Tourism Carbon Emissions and Its Uncertainty Analysis Under the Goal of Low-Carbon Scenic Spots
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作者 Aihong Wang Qiguang Lyu 《Proceedings of Business and Economic Studies》 2023年第2期25-32,共8页
Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of ... Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of China’s national economy,and scenic spots are the main sites of tourism activities.Research on carbon emissions in scenic spots is of great significance for the construction of low-carbon scenic spots and the realization of the dual carbon goal.In this paper,the research on carbon emissions in tourism is reviewed,the current research progress is discussed,and further prospects are made.The research on tourism carbon emissions in China has a good foundation and achieved certain results.However,there are few studies on micro-scales such as scenic spots.The statistical data caliber and measurement methods of carbon emissions are not uniform,and there is a general lack of uncertainty analysis.Future research should focus on building a multi-spatial dimension research system,unifying the statistical caliber and measurement methods of carbon emission data,increasing uncertainty analysis,and ensuring the robustness of research results. 展开更多
关键词 Low-carbon scenic spot Carbon emissions Uncertainty analysis
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Comprehensive Evaluation of Geological and Engineering Sweet Spots of Shale Gas Reservoir: A Case Study of the Luzhou Block, Sichuan Basin
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作者 Yuan Wang Jianfa Wu +3 位作者 Li Fu Haoyong Huang Gang Chen Cheng Chang 《International Journal of Geosciences》 2021年第11期1021-1039,共19页
There is a huge amount of marine shale gas resources in the southern Sichuan Basin in China, and most of the resources are at the buried depth of 3500</span><span style="font-family:""> <... There is a huge amount of marine shale gas resources in the southern Sichuan Basin in China, and most of the resources are at the buried depth of 3500</span><span style="font-family:""> </span><span style="font-family:Verdana;">-</span><span style="font-family:""> </span><span style="font-family:Verdana;">4500 meters. At present, deep shale gas is in the early stage of exploration and development. In order to achieve large-scale efficient development, in addition to optimizing favorable blocks, it is also to identify the optimal target in the vertical direction combine geology, drilling, and fracturing. Therefore, Taking the Longmaxi formation shale in the Luzhou block as the research object, based on drilling, logging, and core experiment data, through single well and 3D geomechanical modeling methods, analyze the characteristics of organic matter abundance, porosity, pore pressure, collapse pressure, mineral composition and in-situ stress of different layers of shale in Longmaxi formation. Systematically summarized the main controlling factors of the “sweet spot” of deep shale gas and establish the comprehensive evaluation system of deep shale gas “sweet spots”, to clarify the optimal “sweet spots” of geology, drilling, and fracturing in the Longmaxi reservoir. Results show that the total organic carbon content, porosity, and gas saturation of the long111 layer are higher than other layers. The Long111 layer has a low collapse pressure and a high compressive strength, the risk of wellbore instability is relatively low. The stress difference coefficient of All layers is less than 0.3, and the brittleness index of the Long111 layer is 62.35%. A complex fracture network is easier to form after fracturing. The conclusion shows that the Long111 layer is the optimal reservoir section of the Longmaxi Formation. Ensure the drilled rate of the Long111 layer and maximize the length of the horizontal section can obtain higher production. 展开更多
关键词 Deep Shale Gas Geological Sweet spots Engineering Sweet spots Geomechanical Modeling
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Prestack inversion based on anisotropic Markov random field-maximum posterior probability inversion and its application to identify shale gas sweet spots 被引量:3
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作者 王康宁 孙赞东 董宁 《Applied Geophysics》 SCIE CSCD 2015年第4期533-544,628,共13页
Economic shale gas production requires hydraulic fracture stimulation to increase the formation permeability. Hydraulic fracturing strongly depends on geomechanical parameters such as Young's modulus and Poisson's r... Economic shale gas production requires hydraulic fracture stimulation to increase the formation permeability. Hydraulic fracturing strongly depends on geomechanical parameters such as Young's modulus and Poisson's ratio. Fracture-prone sweet spots can be predicted by prestack inversion, which is an ill-posed problem; thus, regularization is needed to obtain unique and stable solutions. To characterize gas-bearing shale sedimentary bodies, elastic parameter variations are regarded as an anisotropic Markov random field. Bayesian statistics are adopted for transforming prestack inversion to the maximum posterior probability. Two energy functions for the lateral and vertical directions are used to describe the distribution, and the expectation-maximization algorithm is used to estimate the hyperparameters of the prior probability of elastic parameters. Finally, the inversion yields clear geological boundaries, high vertical resolution, and reasonable lateral continuity using the conjugate gradient method to minimize the objective function. Antinoise and imaging ability of the method were tested using synthetic and real data. 展开更多
关键词 shale gas/oil sweet spot prestack inversion Markov random field
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Accessibility Comparison and Spatial Differentiation of Xi’an Scenic Spots with Different Modes Based on Baidu Real-time Travel 被引量:5
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作者 WANG Li CAO Xiaoshu +1 位作者 LI Tao GAO Xingchuan 《Chinese Geographical Science》 SCIE CSCD 2019年第5期848-860,共13页
A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and adva... A study of the accessibility of a city’s scenic spots via different travel modes can contribute to optimization of tourism-related transportation while improving tourists’ travel-related satisfaction levels and advancing tourism. We systematically analyzed the accessibility of 56 scenic spots in Xi’an City, China, via car and public transport travel modes using the real-time travel function of the Baidu Maps API(Application Programming Interface) along with spatial analysis methods and the modal accessibility gap index of scenic spots. We obtained the following results. First, maximum and minimum travel times using public transport exceeded those using cars. Moreover, the accessibility of scenic spots via cars and public transport presented a circular spatial pattern of increasing travel time from the center to the periphery. Contrasting with travel by public transport, car travel showed a clear time-space compression effect. Second, accessibility of the scenic spots via cars and public transport showed some spatial heterogeneity, with no clear advantages of car accessibility in the central urban area. However, advantages of car accessibility were increasingly evident moving from the center to the periphery. Third, whereas the correlation of the modal accessibility gap index of scenic spots in Xi’an with global space was significantly positive, local spatial interdependence was only evident in some inner city areas and in marginal areas. Moreover, spatial heterogeneity was evident in two regions but was insignificant in other areas, indicating that the spatial interdependence of the modal accessibility gap index in most scenic spots was not apparent in terms of the overall effect of public transport routes, road networks, and the distribution of scenic spots. The improvement of public transport coverage in marginal areas and the optimization of public transport routes in central urban areas are essential tasks for improving travel using public transport in the future. 展开更多
关键词 BAIDU REAL-TIME TRAVEL car ACCESSIBILITY public transport ACCESSIBILITY modal ACCESSIBILITY gap SCENIC spots Xi’an City
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Cultivation and Management of Low-carbon Scenic Spots——A case study of Yuntai Mountain Scenic Area in Henan Provicne of China 被引量:1
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作者 史云 田甜 许晓明 《Journal of Landscape Research》 2011年第4期57-60,64,共5页
After analysis of connotation of low-carbon scenic spots,the paper considered that a perfect low-carbon scenic spot is a comprehensive integrity with satisfying tourists' lowest tourist experience effect as the pr... After analysis of connotation of low-carbon scenic spots,the paper considered that a perfect low-carbon scenic spot is a comprehensive integrity with satisfying tourists' lowest tourist experience effect as the premise and with low energy consumption,low pollution and low emission as the foundation.Low-carbon tourist scenic spots had been classified into three types which are ecological type,cultural type and coupling type of ecology and culture.Representatives of each type of tourist scenic spot were illustrated.It proposed that government should play the leading role in cultivation of low-carbon scenic spot;tourism industry should enhance self supervision;tourism development mode should be transformed and upgrading of tourist products should be realized.By taking Yuntai Mountain Scenic Area of Henan Province for example,based on low-carbon tourist resources,low-carbon development of management,following measures realizing low-carbon economy were put forward:① purifying air quality and beautifying environment of scenic area;② sifting laggard productivity and protecting ecological resources in the scenic area by many means;③ sticking to low-carbon environmental protection concept and completing infrastructure service;④ developing tourist native products and souvenirs based on local resources;⑤ applying electronic access control ticket system,intelligent monitor system and LED information and communication platform,so as to achieve low-carbon management. 展开更多
关键词 Low-carbon SCENIC SPOT CULTIVATION and development Yuntai MOUNTAIN SCENIC Area Management
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Analysis of Names of Twelve Scenic Spots in Baoding Ancient Lotus Pond Garden in China
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作者 果治 段艳霞 +1 位作者 杨玉梅 魏汉朝 《Journal of Landscape Research》 2012年第4期26-28,共3页
By taking the twelve scenic spots in Ancient Lotus Pond Garden as study objects, they have been introduced and their names have been classified in accordance with allege and symbol nomenclature, linguistic rhetoric no... By taking the twelve scenic spots in Ancient Lotus Pond Garden as study objects, they have been introduced and their names have been classified in accordance with allege and symbol nomenclature, linguistic rhetoric nomenclature, narration and description nomenclature, and emotion-endowing and ambition-expressing nomenclature adopted in related articles. Then, the cultural connotations of these scenic spots have been summarized, and Confucian thought and Taoist thought contained in "Surge Including Pavilion" and "High Principle Tower" have been analyzed. The research is aimed at enlightening modern garden workers through illustrating the connotation of the names of scenic spots, so that they can be inspired in the naming process. 展开更多
关键词 ANCIENT LOTUS POND GARDEN TWELVE scenic spots Analysis of NAMES
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Application of Pore Evolution and Fracture Development Coupled Models in the Prediction of Reservoir "Sweet Spots" in Tight Sandstones 被引量:3
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作者 ZHANG Linyan ZHUO Xizhun +3 位作者 MA Licheng CHEN Xiaoshuai SONG Licai ZHOU Xingui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期1051-1052,共2页
The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichm... The Chang-63 reservoir in the Huaqing area has widely developed tight sandstone "thick sand layers, but not reservoirs characterized by rich in oil", and it is thus necessary to further study its oil and gas enrichment law. This study builds porosity and fracture development and evolution models in different deposition environments, through core observation, casting thin section, SEM, porosity and permeability analysis, burial history analysis, and "four-property-relationships" analysis. 展开更多
关键词 Sweet spots in Tight Sandstones Application of Pore Evolution and Fracture Development Coupled Models in the Prediction of Reservoir
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The Hot Spots in Cereal Rusts and Powdery Mildew Research 被引量:3
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作者 CHEN Wan-quan DUAN Xia-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期229-232,共4页
Cereal crops, including wheat, barley, oats, rye, etc., are the major sources of calories and proteins for most of the people in the world as well as in China. Cereal rusts and powdery mildews are very important disea... Cereal crops, including wheat, barley, oats, rye, etc., are the major sources of calories and proteins for most of the people in the world as well as in China. Cereal rusts and powdery mildews are very important diseases occurred on the cereal crops, which caused yield losses at 5-10% in general and even more than 30% while severe epidemics occurred. In recent years, with the global climate change, change of cultivation system and evolution of the pathogens, the world is facing great challenges caused by cereal diseases. 展开更多
关键词 The Hot spots in Cereal Rusts and Powdery Mildew Research THAN
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Egg recognition in Cinereous Tits(Parus cinereus):eggshell spots matter 被引量:2
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作者 Jianping Liu Canchao Yang +2 位作者 Jiangping Yu Haitao Wang Wei Liang 《Avian Research》 CSCD 2019年第4期447-452,共6页
Background:Brood parasitic birds such as cuckoos(Cuculus spp.)can reduce their host’s reproductive success.Such selection pressure on the hosts has driven the evolution of defense behaviors such as egg rejection agai... Background:Brood parasitic birds such as cuckoos(Cuculus spp.)can reduce their host’s reproductive success.Such selection pressure on the hosts has driven the evolution of defense behaviors such as egg rejection against cuckoo parasitism.Studies have shown that Cinereous Tits(Parus cinereus)in China have a good ability for recognizing foreign eggs.However,it is unclear whether egg spots play a role in egg recognition.The aims of our study were to investigate the egg recognition ability of two Cinereous Tit populations in China and to explore the role of spots in egg recognition.Methods:To test the effect of eggshell spots on egg recognition,pure white eggs of the White-rumped Munia(Lonchura striata)and eggs of White-rumped Munia painted with red brown spots were used to simulate experimental parasitism.Results:Egg experiments showed that Cinereous Tits rejected 51.5%of pure white eggs of the White-rumped Munia,but only 14.3%of spotted eggs of the White-rumped Munia.There was a significant difference in egg recognition and rejection rate between the two egg types.Conclusions:We conclude that eggshell spots on Cinereous Tit eggs had a signaling function and may be essential to tits for recognizing and rejecting parasitic eggs. 展开更多
关键词 Brood parasitism Egg recognition Egg rejection Eggshell spots Parus cinereus
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