Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions...Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions,and modeling of the source rocks in the second member of the Eocene Wenchang Formation(Wen 2 Member)in the Northern Shunde Subsag at the southwestern margin of the Pearl River Mouth Basin.The Wen 2 Member hosts excellent,thick lacustrine source rocks with strong longitudinal heterogeneity and an average total organic carbon(TOC)content of over 4.9%.The Wen 2 Member can be divided into three units(I,II,III)from bottom to top.Unit I features excellent source rocks with Type I organic matters(average TOC of 5.9%)primarily sourced from lake organisms;Unit II hosts source rocks dominated by Type II2 organic matters(average TOC of 2.2%),which are originated from mixed sources dominated by terrestrial input.Unit III contains good to excellent source rocks dominated by Type II1 organic matters(average TOC of 4.9%),which are mainly contributed by lake organisms and partially by terrestrial input.Under the background of rapid subsidence and limited source supply during intense rifting period in the Eocene,excellent source rocks were developed in Wen 2 Member in the Northern Shunde Subsag under the coordinated control of warm and humid climate,volcanic activity,and deep-water reducing conditions.During the deposition of Unit I,the warm and humid climate and volcanic activity promoted the proliferation of lake algaes,primarily Granodiscus,resulting in high initial productivity,and deep-water reducing conditions enabled satisfactory preservation of organic matters.These factors jointly controlled the development and occurrence of excellent source rocks.During the deposition of Unit II,a transition from warm to cool and semi-arid paleoclimatic conditions led to a decrease in lake algaes and initial productivity.Additionally,enhanced terrestrial input and shallow-water,weakly oxidizing water conditions caused a significant dilution and decomposition of organic matters,degrading the quality of source rocks.During the deposition of Unit III,when the paleoclimatic conditions are cool and humid,Pediastrum and Botryococcus began to thrive,leading to an increase in productivity.Meanwhile,the reducing environment of semi-deep water facilitated the preservation of excellent source rocks,albeit slightly inferior to those in Unit I.The study results clarify the differential origins and development models of various source rocks in the Shunde Sag,offering valuable guidance for evaluating source rocks and selecting petroleum exploration targets in similar marginal sags.展开更多
Research on the distribution and development of black shales in the Lianggaoshan Formation has been deficient,which has hindered exploration for lacustrine shale oil in the Sichuan Basin.Our study characterized the we...Research on the distribution and development of black shales in the Lianggaoshan Formation has been deficient,which has hindered exploration for lacustrine shale oil in the Sichuan Basin.Our study characterized the well logging data,core samples,outcrops,and geochemistry of black shales in the Lianggaoshan Formation in the Sichuan Basin.Our analysis focused on the lake basin evolution and the migration characteristics,paleoenvironmental features,formation mechanisms,and developmental model of the black shales.The results indicated that black shales in the Lianggaoshan Formation exhibited significant lateral migration,with an overall thickening trend from east to west.Within the 1st Member of the formation,black shale occurred as a single thick layer in the eastern region that gradually thinned toward the central region.Multiple sets of shale developed within the 2nd and 3rd members,and these had lower thicknesses than the 1st Member and migrated toward central Sichuan.Paleoproductivity and terrigenous input were the main factors controlling the deposition of black shales.A semi-humid climate influenced the deposition of black shales,bringing abundant freshwater,terrigenous debris,and nutrients into the basin.Decomposition of organic matter consumed oxygen in sediment and bottom water,causing localized oxygen deficiency in the strata.展开更多
The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,arti...The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider unmanned aerial vehicles(UAVs)as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical references and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy.展开更多
The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,arti...The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider UAVs as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical reference and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy.展开更多
This paper focuses on rural music education in the context of rural revitalization,deeply analyzes its current resource situation,and points out that tangible resources face shortages of teachers,inappropriate textboo...This paper focuses on rural music education in the context of rural revitalization,deeply analyzes its current resource situation,and points out that tangible resources face shortages of teachers,inappropriate textbooks,and outdated teaching facilities,while intangible resources are confronted with the loss of folk music culture and the weakening of educational foundations due to cultural ecological changes.Resources are characterized by dispersion,scarcity,and inefficient utilization.In response to these difficulties,this paper proposes integration paths for teachers,textbooks,teaching facilities,and folk music culture resources.Additionally,it constructs a diversified development model that combines rural tourism with music activities,develops characteristic music education industries,and integrates rural cultural construction.Simultaneously,it identifies funding shortages and outdated concepts as major obstacles and proposes targeted strategies such as expanding funding channels and changing inherent concepts.The aim is to promote the development of rural music education and contribute to the revitalization of rural culture.展开更多
This study systematically reviews the development history and key technological breakthroughs of large gas fields in the Ordos Basin,and summarizes the development models of three gas reservoir types,low-permeability ...This study systematically reviews the development history and key technological breakthroughs of large gas fields in the Ordos Basin,and summarizes the development models of three gas reservoir types,low-permeability carbonate,low-permeability sandstone and tight sandstone,as well as the progress in deep coal-rock gas development.The current challenges and future development directions are also discussed.Mature development models have been formed for the three representative types of gas reservoirs in the Ordos Basin:(1)Low-permeability carbonate reservoir development model featuring groove fine-scale characterization and three-dimensional vertical succession between Upper and Lower Paleozoic formations.(2)Low-permeability sandstone reservoir development model emphasizing horizontal well pressure-depletion production and vertical well pressure-controlled production.(3)Tight sandstone gas reservoir development model focusing on single-well productivity enhancement and well placement optimization.In deep coal-rock gas development,significant progress has been achieved in reservoir evaluation,sweet spot prediction,and geosteering of horizontal wells.The three types of reservoirs have entered the mid-to-late stages of the development,when the main challenge lies in accurately characterizing residual gas,evaluating secondary gas-bearing layers,and developing precise potential-tapping strategies.In contrast,for the early-stage development of deep coal-rock gas,continuous technological upgrades and cost reduction are essential to achieving economically viable large-scale development.Four key directions of future research and technological breakthroughs are proposed:(1)Utilizing dual-porosity(fracture-matrix)modeling techniques in low-permeability carbonate reservoirs to delineate the volume and distribution of remaining gas in secondary pay zones,supporting well pattern optimization and production enhancement of existing wells.(2)Integrating well-log and seismic data to characterize reservoir spatial distribution of successive strata,enhancing drilling success rates in low-permeability sandstone reservoirs.(3)Utilizing the advantages of horizontal wells to penetrate effective reservoirs laterally,achieving meter-scale quantification of small-scale single sand bodies in tight gas reservoirs,and applying high-resolution 3D geological models to clarify the distribution of remaining gas and guide well placement optimization.(4)Further strengthening the evaluation of deep coal-rock gas in terms of resource potential,well type and pattern,reservoir stimulation,single-well performance,and economic viability.展开更多
Objective To develop a risk model for predicting later development of diabetic nephropathy （DN） in Chinese people with type 2 diabetes mellitus （T2DM） and evaluate its performance with independent validation. Meth...Objective To develop a risk model for predicting later development of diabetic nephropathy （DN） in Chinese people with type 2 diabetes mellitus （T2DM） and evaluate its performance with independent validation. Methods We used data collected from the project ＇Comprehensive Research on the Prevention and Control of Diabetes＇, which was a community-based study conducted by the Jiangsu Center for Disease Control and Prevention in 2013. A total of 11,771 eligible participants were included in our study. The endpoint was a clear diagnosis of DN. Data was divided into two components： a training set for model development and a test set for validation. The Cox proportional hazard regression was used for survival analysis in men and women. The model＇s performance was evaluated by discrimination and calibration. Results The incidence （cases per 10,000 person-years） of DN was 9.95 （95% CI; 8.66-11.43） in women and 11.28 （95% CI; 9.77-13.03） in men. Factors including diagnosis age, location, body mass index, high-density-lipoprotein cholesterol, creatinine, hypertension, dyslipidemia, retinopathy, diet control, and physical activity were significant in the final model. The model showed high discrimination and good calibration. Conclusion The risk model for predicting DN in people with T2DM can be used in clinical practice for improving the quality of risk management and intervention.展开更多
[Objective] To investigate the appropriate low-carbon agriculture model in Southern Jiangsu Province. [Method] Through the analysis of regional features in Southern Jiangsu and several matured low-carbon agriculture d...[Objective] To investigate the appropriate low-carbon agriculture model in Southern Jiangsu Province. [Method] Through the analysis of regional features in Southern Jiangsu and several matured low-carbon agriculture development models at present, the low-carbon agriculture development modes suitable for Southern Jiangsu were investigated, and corresponding supporting measures for the development of the models were put forward. [Result] Low-carbon agriculture is the environment- friendly agriculture which achieves low emissions, low pollution, high efficiency and high-yield through efficient recycling of energy and resources and continuous im- provements on ecological environment. With a variety of development models, the specific development model for practical use should be determined according to the local conditions, and supported by corresponding supporting measures, to achieve the rapid development of low-carbon agriculture. [Conclusion] This study laid the foundation for the development of low-carbon agriculture model in Southern Jiangsu.展开更多
Serious desertification caused by human activity and climate change,in addition to water loss and soil erosion related to arsenic sandstone in the Mu Us Sandy Land,lead to severe scarcity of soil and water resources,w...Serious desertification caused by human activity and climate change,in addition to water loss and soil erosion related to arsenic sandstone in the Mu Us Sandy Land,lead to severe scarcity of soil and water resources,which causes worse local agricultural conditions accordingly.Many physical properties of arsenic sandstone is complementary with that of sand,arsenic sandstone is therefore supposed to be blended to enhance water productivity and arability of sandy land.Container experiments are carried out to study the enhancement of water holding capacity of the mixture,the blending ratio of arsenic sandstone and sand,and the proper size of the arsenic sandstone particles,respectively.The results of the experiments show that particle size of 4 cm with a ratio of 1∶2 between arsenic sandstone and sand are the proper parameters on blending.Both water content and fertility increase after blending.Water use efficiency in the mixture is 2.7 times higher than that in sand by the water release curves from experiments.Therefore,a new sand control and development model,including arsenic sandstone blending with sand,efficient water irrigation management and reasonable farming system,is put forward to control and develop sandy land so that water-saving agriculture could be developed.Demonstration of potato planting about 153.1 ha in area in the Mu Us Sandy Land in China indicates that water consumption is 3018 m3/ha in the whole growth period.It means that about 61%of irrigation water can be saved compared with water use in coarse sand without treatment.Recycle economic mode and positive feedback of sand resource-crop planting-soil resource are constructed,which changes sand into arable soil and make it possible to develop water-saving agriculture on it.The proposed model will be helpful for soil-water resources utilization and management in the Mu Us Sandy Land.展开更多
The sustainability of regional rural development depends on the integrated status and the coordination between rural resources-environment conditions and rural socioeco- nomic development. In this paper a diagnostic i...The sustainability of regional rural development depends on the integrated status and the coordination between rural resources-environment conditions and rural socioeco- nomic development. In this paper a diagnostic indicator system is proposed to appraise four representative rural development models such as Mentougou model, Taicang model, Yueqing model and Qionghai model in the eastern coastal region of China from the integrated perspective of population, resources, environment, and development. In conclusion, the formation and evolution of these diverse rural deveJopment models are the direct response to the very different characteristics in the environment, market demand, and regional culture. These models are common in that their sustainability depends on the scientific guidance of the regional development functional positioning, strong intra-regional interactions, and self-adaptability to the external conditions.展开更多
Rural tourism in China,has undergone a rapid development in the last three decades.It is an emerging and effective catalyst that promotes industrial restructuring,agricultural development and the upgrading of rural ar...Rural tourism in China,has undergone a rapid development in the last three decades.It is an emerging and effective catalyst that promotes industrial restructuring,agricultural development and the upgrading of rural areas.However,there remains little understanding about the core issues of rural tourism in China:the exact connotation,the principles,the development models and the future directions.This review paper identifies the key issues based on literature analysis,national statistics and press reports to form a general picture of the past,the current and the future prospects of China's rural tourism.The paper firstly addresses the definition,content and principles of rural tourism,and then provides an overview and brief evaluation of the progress and the current development models in China.Finally,based on the analysis of the experiences and problems,the authors sum up with five pathways of the future development of China's rural tourism from the perspective of rural tourism resources,product,market and promotion.展开更多
From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and...From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation.展开更多
Cities are the key areas for human beings to achieve sustainable development goals in the future.Estuarine cities are a special type of coastal city in urgent need of a clear definition.This paper proposed that estuar...Cities are the key areas for human beings to achieve sustainable development goals in the future.Estuarine cities are a special type of coastal city in urgent need of a clear definition.This paper proposed that estuarine cities are cities developed on the coast where rivers and oceans meet and defined four connotations,including the intersection of rivers and marine water systems,the coordinated development of land and oceans,the location advantages of connecting rivers and seas,and the important fragility of the ecological environment.We used Hydro SHEDS,OSM,GPW,and urban socioeconomic statistics and selected 50 estuarine cities with large rivers as representatives to summarize the main geographical basis and socioeconomic characteristics.Cities are primarily found in low-altitude,flat regions with average annual temperatures that mainly vary from 10℃to 25℃,relatively abundant precipitation,and extensive biological resources.There are substantial variations in the socioeconomic features of estuarine cities.We proposed eight development patterns,including open and inclusive city spirit,high-quality livable cities,high-quality development driven by innovation,integration of internal and external communication with ports and cities,construction of an international financial center,ecological environment protection and restoration,active promotion of cultural tourism,and positive international exchanges.展开更多
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
A case study is presented of a regional development model for valley economies in the mountain areas of Beijing, China. The nature and framework of the valley economy model are described and the development of the mod...A case study is presented of a regional development model for valley economies in the mountain areas of Beijing, China. The nature and framework of the valley economy model are described and the development of the model, which is specific to the mountain areas of Beijing, is analyzed. Five different valley economy models applied in the Beijing mountain areas are compared. The major purpose of the valley economy model is to develop the regional economy, including the selection of appropriate industries, the allocation of industrial space, the establishment of supply chains and the integration of various industries. Pilot experiments using the valley economy model have been conducted in seven counties(districts) in Beijing: Pinggu, Huairou, Changping, Mentougou, and Fangshan districts, and Yanqing and Miyun counties. Five models for developing the Beijing mountain areas have been explored, including: creative cultural industries, characteristic industry clusters, the promotion of large tourist areas, natural scenic tourism and folk cultural tourism. Each model has its own unique features and potential to help in the regional development of mountain areas.展开更多
The reservoir space,types and distribution characteristics of karst carbonate gas reservoirs in the fourth member of Sinian Dengying Formation(Deng 4 Member)in central Sichuan Basin are analyzed based on the drilling,...The reservoir space,types and distribution characteristics of karst carbonate gas reservoirs in the fourth member of Sinian Dengying Formation(Deng 4 Member)in central Sichuan Basin are analyzed based on the drilling,logging and seismic data.A development model of karst reservoirs is constructed to support the high-efficiency development of gas pools.The research shows that the reservoirs in Deng 4 Member have mainly small-scale karst vugs and fractures as storage space,and can be divided into three types,fracture-vug,pore-vug and pore types.The development patterns of the karst reservoirs are determined.On the plane,the karst layers increase from 65 m to 170 m in thickness from the karst platform to the karst slope,and the high-quality reservoirs increase from 25.0 m to 42.2 m in thickness;vertically,the reservoirs at the top of Deng 4 Member appear in multiple layers,and show along-bedding and along fracture dissolution characteristics.The reservoirs at the bottom are characterized by the dissolution parallel to the water level during the karstification period,and have 3-5 large-scale fracture-cave systems.Based on the reservoir development characteristics and the genetic mechanism,three types of reservoir development models of karst reservoir are established,i.e.,bed-dissolved body,fracture-dissolved body and paleohorizon-dissolved body.The construction of karst reservoir development models and seismic response characteristics of the three types of reservoirs can provide parameter for well placement and trajectory design,and substantially improve productivity and development indices of individual wells and gas reservoirs.The designed production capacity of the gas reservoir has enhanced from the initial 3.6 billion to 6 billion cubic meters,making the profit of the reservoir development increase noticeably.展开更多
Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient...Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient towns, ttaditional cultute, die artistic envifonment, and medical cafe, and put forward relevant planning strategies from five aspects, namely, site selection, silver industry chain, functional demand, operation management mode, and safety guarantee system, providing a reference for the construction and development of domestic tourism-based retitement towns.展开更多
In the context of the new urbanization,the characteristic town,as a new hotspot to developing rapidly to explore the industry,humanities,community integration town model,a urbanization and high-tech industry developme...In the context of the new urbanization,the characteristic town,as a new hotspot to developing rapidly to explore the industry,humanities,community integration town model,a urbanization and high-tech industry development booster,by the government and developers attention.At the same time,the green development model applies to the characteristic town of industrial upgrading and transformation,guiding the future characteristic town of green economic industry development direction.This paper studies the green development model of the characteristic town,and puts forward the implementation of the green industry through the greening industry structure,promoting green consumption and optimizing the green management.展开更多
BACKGROUND Acute kidney injury(AKI)after coronary artery bypass graft(CABG)surgery is associated with significant morbidity and mortality.This retrospective study aimed to establish a risk score for postoperative AKI ...BACKGROUND Acute kidney injury(AKI)after coronary artery bypass graft(CABG)surgery is associated with significant morbidity and mortality.This retrospective study aimed to establish a risk score for postoperative AKI in a Chinese population.METHODS A total of 1138 patients undergoing CABG were collected from September 2018 to May 2020 and divided into a derivation and validation cohort.AKI was defined according to the Kidney Disease Improving Global Outcomes(KDIGO)criteria.Multivariable logistic regression analysis was used to determine the independent predictors of AKI,and the predictive ability of the model was determined using a receiver operating characteristic(ROC)curve.RESULTS The incidence of cardiac surgery–associated acute kidney injury(CSA-AKI)was 24.17%,and 0.53%of AKI patients required dialysis(AKI-D).Among the derivation cohort,multivariable logistic regression showed that age≥70 years,body mass index(BMI)≥25 kg/m2,estimated glomerular filtration rate(eGFR)≤60 mL/min per 1.73 m2,ejection fraction(EF)≤45%,use of statins,red blood cell transfusion,use of adrenaline,intra-aortic balloon pump(IABP)implantation,postoperative low cardiac output syndrome(LCOS)and reoperation for bleeding were independent predictors.The predictive model was scored from 0 to32 points with three risk categories.The AKI frequencies were as follows:0-8 points(15.9%),9-17 points(36.5%)and≥18 points(90.4%).The area under of the ROC curve was 0.730(95%CI:0.691-0.768)in the derivation cohort.The predictive index had good discrimination in the validation cohort,with an area under the curve of 0.735(95%CI:0.655-0.815).The model was well calibrated according to the Hosmer-Lemeshow test(P=0.372).CONCLUSION The performance of the prediction model was valid and accurate in predicting KDIGO-AKI after CABG surgery in Chinese patients,and could improve the early prognosis and clinical interventions.展开更多
基金Supported by the Research Project of China National Offshore Oil Corporation(SCKY-2023-HN-3)。
文摘Based on the comprehensive analysis of data from petrology and mineralogy,well logging,seismic surveys,paleontology,and geochemistry,a detailed research was conducted on paleoenvironmental and paleoclimatic conditions,and modeling of the source rocks in the second member of the Eocene Wenchang Formation(Wen 2 Member)in the Northern Shunde Subsag at the southwestern margin of the Pearl River Mouth Basin.The Wen 2 Member hosts excellent,thick lacustrine source rocks with strong longitudinal heterogeneity and an average total organic carbon(TOC)content of over 4.9%.The Wen 2 Member can be divided into three units(I,II,III)from bottom to top.Unit I features excellent source rocks with Type I organic matters(average TOC of 5.9%)primarily sourced from lake organisms;Unit II hosts source rocks dominated by Type II2 organic matters(average TOC of 2.2%),which are originated from mixed sources dominated by terrestrial input.Unit III contains good to excellent source rocks dominated by Type II1 organic matters(average TOC of 4.9%),which are mainly contributed by lake organisms and partially by terrestrial input.Under the background of rapid subsidence and limited source supply during intense rifting period in the Eocene,excellent source rocks were developed in Wen 2 Member in the Northern Shunde Subsag under the coordinated control of warm and humid climate,volcanic activity,and deep-water reducing conditions.During the deposition of Unit I,the warm and humid climate and volcanic activity promoted the proliferation of lake algaes,primarily Granodiscus,resulting in high initial productivity,and deep-water reducing conditions enabled satisfactory preservation of organic matters.These factors jointly controlled the development and occurrence of excellent source rocks.During the deposition of Unit II,a transition from warm to cool and semi-arid paleoclimatic conditions led to a decrease in lake algaes and initial productivity.Additionally,enhanced terrestrial input and shallow-water,weakly oxidizing water conditions caused a significant dilution and decomposition of organic matters,degrading the quality of source rocks.During the deposition of Unit III,when the paleoclimatic conditions are cool and humid,Pediastrum and Botryococcus began to thrive,leading to an increase in productivity.Meanwhile,the reducing environment of semi-deep water facilitated the preservation of excellent source rocks,albeit slightly inferior to those in Unit I.The study results clarify the differential origins and development models of various source rocks in the Shunde Sag,offering valuable guidance for evaluating source rocks and selecting petroleum exploration targets in similar marginal sags.
基金funded by Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(2020CX050103).
文摘Research on the distribution and development of black shales in the Lianggaoshan Formation has been deficient,which has hindered exploration for lacustrine shale oil in the Sichuan Basin.Our study characterized the well logging data,core samples,outcrops,and geochemistry of black shales in the Lianggaoshan Formation in the Sichuan Basin.Our analysis focused on the lake basin evolution and the migration characteristics,paleoenvironmental features,formation mechanisms,and developmental model of the black shales.The results indicated that black shales in the Lianggaoshan Formation exhibited significant lateral migration,with an overall thickening trend from east to west.Within the 1st Member of the formation,black shale occurred as a single thick layer in the eastern region that gradually thinned toward the central region.Multiple sets of shale developed within the 2nd and 3rd members,and these had lower thicknesses than the 1st Member and migrated toward central Sichuan.Paleoproductivity and terrigenous input were the main factors controlling the deposition of black shales.A semi-humid climate influenced the deposition of black shales,bringing abundant freshwater,terrigenous debris,and nutrients into the basin.Decomposition of organic matter consumed oxygen in sediment and bottom water,causing localized oxygen deficiency in the strata.
文摘The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider unmanned aerial vehicles(UAVs)as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical references and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy.
文摘The“14th Five-Year Plan”and the Long-Range Objectives Through the Year 2035 propose to strengthen the construction of strategic emerging industrial clusters,promote the deep integration of the internet,big data,artificial intelligence,blockchain technology,etc.with the real economy,facilitate the development of advanced manufacturing,and consider UAVs as an important breakthrough,providing significant opportunities for the development of the UAV industry.Therefore,this article takes the current status of the UAV industry development as a starting point,analyzes the exploration and practice of the UAV development model based on the low-altitude economy,and discusses strategic suggestions to promote the development of UAVs empowered by the low-altitude economy.Through analysis,this article aims to provide theoretical reference and practical guidance for promoting the sustainable development of the UAV industry under the wave of the low-altitude economy.
文摘This paper focuses on rural music education in the context of rural revitalization,deeply analyzes its current resource situation,and points out that tangible resources face shortages of teachers,inappropriate textbooks,and outdated teaching facilities,while intangible resources are confronted with the loss of folk music culture and the weakening of educational foundations due to cultural ecological changes.Resources are characterized by dispersion,scarcity,and inefficient utilization.In response to these difficulties,this paper proposes integration paths for teachers,textbooks,teaching facilities,and folk music culture resources.Additionally,it constructs a diversified development model that combines rural tourism with music activities,develops characteristic music education industries,and integrates rural cultural construction.Simultaneously,it identifies funding shortages and outdated concepts as major obstacles and proposes targeted strategies such as expanding funding channels and changing inherent concepts.The aim is to promote the development of rural music education and contribute to the revitalization of rural culture.
文摘This study systematically reviews the development history and key technological breakthroughs of large gas fields in the Ordos Basin,and summarizes the development models of three gas reservoir types,low-permeability carbonate,low-permeability sandstone and tight sandstone,as well as the progress in deep coal-rock gas development.The current challenges and future development directions are also discussed.Mature development models have been formed for the three representative types of gas reservoirs in the Ordos Basin:(1)Low-permeability carbonate reservoir development model featuring groove fine-scale characterization and three-dimensional vertical succession between Upper and Lower Paleozoic formations.(2)Low-permeability sandstone reservoir development model emphasizing horizontal well pressure-depletion production and vertical well pressure-controlled production.(3)Tight sandstone gas reservoir development model focusing on single-well productivity enhancement and well placement optimization.In deep coal-rock gas development,significant progress has been achieved in reservoir evaluation,sweet spot prediction,and geosteering of horizontal wells.The three types of reservoirs have entered the mid-to-late stages of the development,when the main challenge lies in accurately characterizing residual gas,evaluating secondary gas-bearing layers,and developing precise potential-tapping strategies.In contrast,for the early-stage development of deep coal-rock gas,continuous technological upgrades and cost reduction are essential to achieving economically viable large-scale development.Four key directions of future research and technological breakthroughs are proposed:(1)Utilizing dual-porosity(fracture-matrix)modeling techniques in low-permeability carbonate reservoirs to delineate the volume and distribution of remaining gas in secondary pay zones,supporting well pattern optimization and production enhancement of existing wells.(2)Integrating well-log and seismic data to characterize reservoir spatial distribution of successive strata,enhancing drilling success rates in low-permeability sandstone reservoirs.(3)Utilizing the advantages of horizontal wells to penetrate effective reservoirs laterally,achieving meter-scale quantification of small-scale single sand bodies in tight gas reservoirs,and applying high-resolution 3D geological models to clarify the distribution of remaining gas and guide well placement optimization.(4)Further strengthening the evaluation of deep coal-rock gas in terms of resource potential,well type and pattern,reservoir stimulation,single-well performance,and economic viability.
基金supported by grants from Jiangsu Provincial Medical Innovation Team Program[grant number K201105]Jiangsu Provincial Fourth‘333 Project’[grant number BRA2013107]
文摘Objective To develop a risk model for predicting later development of diabetic nephropathy （DN） in Chinese people with type 2 diabetes mellitus （T2DM） and evaluate its performance with independent validation. Methods We used data collected from the project ＇Comprehensive Research on the Prevention and Control of Diabetes＇, which was a community-based study conducted by the Jiangsu Center for Disease Control and Prevention in 2013. A total of 11,771 eligible participants were included in our study. The endpoint was a clear diagnosis of DN. Data was divided into two components： a training set for model development and a test set for validation. The Cox proportional hazard regression was used for survival analysis in men and women. The model＇s performance was evaluated by discrimination and calibration. Results The incidence （cases per 10,000 person-years） of DN was 9.95 （95% CI; 8.66-11.43） in women and 11.28 （95% CI; 9.77-13.03） in men. Factors including diagnosis age, location, body mass index, high-density-lipoprotein cholesterol, creatinine, hypertension, dyslipidemia, retinopathy, diet control, and physical activity were significant in the final model. The model showed high discrimination and good calibration. Conclusion The risk model for predicting DN in people with T2DM can be used in clinical practice for improving the quality of risk management and intervention.
基金Supported by the National Natural Science Foundation of China(70901035)~~
文摘[Objective] To investigate the appropriate low-carbon agriculture model in Southern Jiangsu Province. [Method] Through the analysis of regional features in Southern Jiangsu and several matured low-carbon agriculture development models at present, the low-carbon agriculture development modes suitable for Southern Jiangsu were investigated, and corresponding supporting measures for the development of the models were put forward. [Result] Low-carbon agriculture is the environment- friendly agriculture which achieves low emissions, low pollution, high efficiency and high-yield through efficient recycling of energy and resources and continuous im- provements on ecological environment. With a variety of development models, the specific development model for practical use should be determined according to the local conditions, and supported by corresponding supporting measures, to achieve the rapid development of low-carbon agriculture. [Conclusion] This study laid the foundation for the development of low-carbon agriculture model in Southern Jiangsu.
基金Under the auspices of National Natural Science Foundation of China(No.51079120)Education Department Research Program of Shaanxi Province(No.12JK0481)Water Conservancy Science and Technology Plan of Shaanxi Province(No.2012-07)
文摘Serious desertification caused by human activity and climate change,in addition to water loss and soil erosion related to arsenic sandstone in the Mu Us Sandy Land,lead to severe scarcity of soil and water resources,which causes worse local agricultural conditions accordingly.Many physical properties of arsenic sandstone is complementary with that of sand,arsenic sandstone is therefore supposed to be blended to enhance water productivity and arability of sandy land.Container experiments are carried out to study the enhancement of water holding capacity of the mixture,the blending ratio of arsenic sandstone and sand,and the proper size of the arsenic sandstone particles,respectively.The results of the experiments show that particle size of 4 cm with a ratio of 1∶2 between arsenic sandstone and sand are the proper parameters on blending.Both water content and fertility increase after blending.Water use efficiency in the mixture is 2.7 times higher than that in sand by the water release curves from experiments.Therefore,a new sand control and development model,including arsenic sandstone blending with sand,efficient water irrigation management and reasonable farming system,is put forward to control and develop sandy land so that water-saving agriculture could be developed.Demonstration of potato planting about 153.1 ha in area in the Mu Us Sandy Land in China indicates that water consumption is 3018 m3/ha in the whole growth period.It means that about 61%of irrigation water can be saved compared with water use in coarse sand without treatment.Recycle economic mode and positive feedback of sand resource-crop planting-soil resource are constructed,which changes sand into arable soil and make it possible to develop water-saving agriculture on it.The proposed model will be helpful for soil-water resources utilization and management in the Mu Us Sandy Land.
基金National Natural Science Foundation of China, No.40635029 No.40871257Knowledge Innovation Program of Chinese Academy of Sciences, No.KSCX-YW-09
文摘The sustainability of regional rural development depends on the integrated status and the coordination between rural resources-environment conditions and rural socioeco- nomic development. In this paper a diagnostic indicator system is proposed to appraise four representative rural development models such as Mentougou model, Taicang model, Yueqing model and Qionghai model in the eastern coastal region of China from the integrated perspective of population, resources, environment, and development. In conclusion, the formation and evolution of these diverse rural deveJopment models are the direct response to the very different characteristics in the environment, market demand, and regional culture. These models are common in that their sustainability depends on the scientific guidance of the regional development functional positioning, strong intra-regional interactions, and self-adaptability to the external conditions.
基金supported by a grant from the major projects of the National Social Science Foundation of China (10zd&051)National Natural Science Foundation Item of China(No.41171435 )from the United Nations(UNDP/CPR/040/SPA)
文摘Rural tourism in China,has undergone a rapid development in the last three decades.It is an emerging and effective catalyst that promotes industrial restructuring,agricultural development and the upgrading of rural areas.However,there remains little understanding about the core issues of rural tourism in China:the exact connotation,the principles,the development models and the future directions.This review paper identifies the key issues based on literature analysis,national statistics and press reports to form a general picture of the past,the current and the future prospects of China's rural tourism.The paper firstly addresses the definition,content and principles of rural tourism,and then provides an overview and brief evaluation of the progress and the current development models in China.Finally,based on the analysis of the experiences and problems,the authors sum up with five pathways of the future development of China's rural tourism from the perspective of rural tourism resources,product,market and promotion.
文摘From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation.
基金The Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA23100301The Chinese Academy of Sciences Basic Frontier Science Research Program from 0 to 1 Original Innovation Project,No.ZDBS-LYD-QC005National Natural Science Foundation of China,No.42171204。
文摘Cities are the key areas for human beings to achieve sustainable development goals in the future.Estuarine cities are a special type of coastal city in urgent need of a clear definition.This paper proposed that estuarine cities are cities developed on the coast where rivers and oceans meet and defined four connotations,including the intersection of rivers and marine water systems,the coordinated development of land and oceans,the location advantages of connecting rivers and seas,and the important fragility of the ecological environment.We used Hydro SHEDS,OSM,GPW,and urban socioeconomic statistics and selected 50 estuarine cities with large rivers as representatives to summarize the main geographical basis and socioeconomic characteristics.Cities are primarily found in low-altitude,flat regions with average annual temperatures that mainly vary from 10℃to 25℃,relatively abundant precipitation,and extensive biological resources.There are substantial variations in the socioeconomic features of estuarine cities.We proposed eight development patterns,including open and inclusive city spirit,high-quality livable cities,high-quality development driven by innovation,integration of internal and external communication with ports and cities,construction of an international financial center,ecological environment protection and restoration,active promotion of cultural tourism,and positive international exchanges.
文摘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.
基金supported by the National Natural Science Foundation of China(Grant No.4120112941125005)+2 种基金the Hunan Provincial Natural Science Foundation of China(Grant No.12JJ3037)the Hunan Provincial Philosophy and Social Sciences Foundation of China(Grant No.11JD06)the Hengyang Normal University Youth Foundation in Hunan Province of China(Grant No.11A27)
文摘A case study is presented of a regional development model for valley economies in the mountain areas of Beijing, China. The nature and framework of the valley economy model are described and the development of the model, which is specific to the mountain areas of Beijing, is analyzed. Five different valley economy models applied in the Beijing mountain areas are compared. The major purpose of the valley economy model is to develop the regional economy, including the selection of appropriate industries, the allocation of industrial space, the establishment of supply chains and the integration of various industries. Pilot experiments using the valley economy model have been conducted in seven counties(districts) in Beijing: Pinggu, Huairou, Changping, Mentougou, and Fangshan districts, and Yanqing and Miyun counties. Five models for developing the Beijing mountain areas have been explored, including: creative cultural industries, characteristic industry clusters, the promotion of large tourist areas, natural scenic tourism and folk cultural tourism. Each model has its own unique features and potential to help in the regional development of mountain areas.
基金Supported by the National Science and Technology Major Project of China(2016ZX05015)PetroChina Science and Technology Project(2021DJ1504).
文摘The reservoir space,types and distribution characteristics of karst carbonate gas reservoirs in the fourth member of Sinian Dengying Formation(Deng 4 Member)in central Sichuan Basin are analyzed based on the drilling,logging and seismic data.A development model of karst reservoirs is constructed to support the high-efficiency development of gas pools.The research shows that the reservoirs in Deng 4 Member have mainly small-scale karst vugs and fractures as storage space,and can be divided into three types,fracture-vug,pore-vug and pore types.The development patterns of the karst reservoirs are determined.On the plane,the karst layers increase from 65 m to 170 m in thickness from the karst platform to the karst slope,and the high-quality reservoirs increase from 25.0 m to 42.2 m in thickness;vertically,the reservoirs at the top of Deng 4 Member appear in multiple layers,and show along-bedding and along fracture dissolution characteristics.The reservoirs at the bottom are characterized by the dissolution parallel to the water level during the karstification period,and have 3-5 large-scale fracture-cave systems.Based on the reservoir development characteristics and the genetic mechanism,three types of reservoir development models of karst reservoir are established,i.e.,bed-dissolved body,fracture-dissolved body and paleohorizon-dissolved body.The construction of karst reservoir development models and seismic response characteristics of the three types of reservoirs can provide parameter for well placement and trajectory design,and substantially improve productivity and development indices of individual wells and gas reservoirs.The designed production capacity of the gas reservoir has enhanced from the initial 3.6 billion to 6 billion cubic meters,making the profit of the reservoir development increase noticeably.
基金Sponsored by National Natural Science Fund of China(51568025)Humanities and Social Sciences Project of Colleges and Universities in Jiangxi(JC161017)
文摘Based on the analysis of the tourism-based fetkement models this papet proposed five types of retirement towns, which combined the eldercare industry with ecological conditions, the style and features of ancient towns, ttaditional cultute, die artistic envifonment, and medical cafe, and put forward relevant planning strategies from five aspects, namely, site selection, silver industry chain, functional demand, operation management mode, and safety guarantee system, providing a reference for the construction and development of domestic tourism-based retitement towns.
基金supported by the Project for Master Degree Candidate at Guizhou University of Finance and Economics(Grant No.2017YAN128)
文摘In the context of the new urbanization,the characteristic town,as a new hotspot to developing rapidly to explore the industry,humanities,community integration town model,a urbanization and high-tech industry development booster,by the government and developers attention.At the same time,the green development model applies to the characteristic town of industrial upgrading and transformation,guiding the future characteristic town of green economic industry development direction.This paper studies the green development model of the characteristic town,and puts forward the implementation of the green industry through the greening industry structure,promoting green consumption and optimizing the green management.
基金supported by National Natural S cience Foundation of China(81570373)。
文摘BACKGROUND Acute kidney injury(AKI)after coronary artery bypass graft(CABG)surgery is associated with significant morbidity and mortality.This retrospective study aimed to establish a risk score for postoperative AKI in a Chinese population.METHODS A total of 1138 patients undergoing CABG were collected from September 2018 to May 2020 and divided into a derivation and validation cohort.AKI was defined according to the Kidney Disease Improving Global Outcomes(KDIGO)criteria.Multivariable logistic regression analysis was used to determine the independent predictors of AKI,and the predictive ability of the model was determined using a receiver operating characteristic(ROC)curve.RESULTS The incidence of cardiac surgery–associated acute kidney injury(CSA-AKI)was 24.17%,and 0.53%of AKI patients required dialysis(AKI-D).Among the derivation cohort,multivariable logistic regression showed that age≥70 years,body mass index(BMI)≥25 kg/m2,estimated glomerular filtration rate(eGFR)≤60 mL/min per 1.73 m2,ejection fraction(EF)≤45%,use of statins,red blood cell transfusion,use of adrenaline,intra-aortic balloon pump(IABP)implantation,postoperative low cardiac output syndrome(LCOS)and reoperation for bleeding were independent predictors.The predictive model was scored from 0 to32 points with three risk categories.The AKI frequencies were as follows:0-8 points(15.9%),9-17 points(36.5%)and≥18 points(90.4%).The area under of the ROC curve was 0.730(95%CI:0.691-0.768)in the derivation cohort.The predictive index had good discrimination in the validation cohort,with an area under the curve of 0.735(95%CI:0.655-0.815).The model was well calibrated according to the Hosmer-Lemeshow test(P=0.372).CONCLUSION The performance of the prediction model was valid and accurate in predicting KDIGO-AKI after CABG surgery in Chinese patients,and could improve the early prognosis and clinical interventions.
