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Morphological Evolution of Self-Assembled Sodium Dodecyl Sulfate/Dodecyltrimethylammonium Bromide@Epoxy-β-Cyclodextrin Supramolecular Aggregates Induced by Temperature
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作者 Qingran Meng Wenwen Xu +2 位作者 Zuobing Xiao Qinfei Ke Xingran Kou 《Journal of Renewable Materials》 EI CAS 2024年第4期629-641,共13页
Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interact... Bio-based cyclodextrins(CDs)are a common research object in supramolecular chemistry.The special cavity structure of CDs can form supramolecular self-assemblies such as vesicles and microcrystals through weak interaction with guest molecules.The different forms of supramolecular self-assemblies can be transformed into each other under certain conditions.The regulation of supramolecular self-assembly is not only helpful to understand the self-assembly principle,but also beneficial to its application.In the present study,the self-assembly behavior of epoxy-β-cyclodextrin(EP-β-CD)and mixed anionic and cationic surfactant system(sodium dodecyl sulfate/dodecyltrimethylammonium bromide,SDS/DTAB)in aqueous solution was studied.Morphological and particle size characterization found that the SDS/DTAB@EP-β-CD complex,as the basic building unit,self-assembled into worm-like micelles at lower temperatures and vesicles at higher temperatures.Nuclear magnetic resonance(NMR)and Fourier transform infrared spectroscopy(FT-IR)analysis revealed that the driving force for the formation of vesicles and worm-like micelles was the hydrogen bonds between EP-β-CD molecules,while water molecules played an important role in promoting vesicle formation between SDS/DTAB@EP-β-CD units.Herein,the mechanism of the morphologic transformation of SDS/DTAB@EP-β-CD supramolecular aggregates induced by temperature was elucidated by exploring the self-assembly process,which may provide an excellent basis for the development of delivery carriers. 展开更多
关键词 Epoxy-β-cyclodextrin SDS/DTAB SELF-ASSEMBLY TEMPERATURE morphological evolution
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Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW China
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作者 TIAN Fanglei GUO Tonglou +6 位作者 HE Dengfa GU Zhanyu MENG Xianwu WANG Renfu WANG Ying ZHANG Weikang LU Guo 《Petroleum Exploration and Development》 SCIE 2024年第3期604-620,共17页
With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,... With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending FI19 and FI20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear deformation.Among them,the FI19 and FI20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped ribbon.And before Permian and during the Early Triassic,the FI19 and FI20 fault zones underwent at least two periods of structural superimposition.Besides,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped arrangement.And before Permian,they had formed almost,restricting the eastward growth and propagation of the FI19 fault zone.The FI19 and FI20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation peaks.If there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the FI19 and FI20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration. 展开更多
关键词 transtensional(strike-slip)fault three-dimensional structural model structural evolution petroleum geological significance Ziyang area Sichuan Basin
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Acute Kidney Injury in the Nephrology Department of the Brazzaville University Hospital: Epidemiological, Clinical and Evolutionary Aspects
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作者 Daniel Tony Eyeni Sinomono Gael Honal Mahoungou +3 位作者 Eric Gabdzali Ngabé Audrey Missamou Mavi Bouloupy Richard Loumingou 《Open Journal of Nephrology》 2024年第2期196-215,共20页
Introduction: Acute kidney injury (AKI) is defined as a sudden and reversible deterioration in renal function. It is a life-threatening condition in hospitalized patients. Our objectives were to determine the prevalen... Introduction: Acute kidney injury (AKI) is defined as a sudden and reversible deterioration in renal function. It is a life-threatening condition in hospitalized patients. Our objectives were to determine the prevalence of AKI in a nephrology department, list the causes, describe the evolutionary profile and identify the factors associated with death. Patients and Methods: We reviewed the records of patients hospitalised between 1 January 2016 and 31 October 2020 in the nephrology department of Brazzaville University Hospital. We included patients aged at least 18 years whose discharge diagnosis included the item AKI. Study variables were socio-demographic data, clinical and paraclinical signs, stage and type of AKI, etiology and evolutionary profile. Results: Of the 1823 patients hospitalised, 244 (13.38%) were hospitalised for AKI. Of these, 60.2% were boys and 39.8% girls, with an average age of 47 19 years. The average consultation time was 10 6.5 days. AKI was stage 3 in 69.57% of cases. It was functional, organic and obstructive in the order of 55.28%, 36.02% and 8.69%. Dialysis was indicated in 62 patients (38.51%) and performed in 24 patients (14.9%). In-hospital mortality was 27.95%, with an average hospital stay of 9.6 5.8 days. Metabolic acidosis and anemia were the main causes of death in 14.28% and 4.35% of patients respectively. Factors associated with death were male sex, socioeconomic level, coma, indication for dialysis and absence of dialysis, with a p Conclusion: AKI is more common in young adult males. Mortality is relatively low. Improving prognosis requires early management and access to dialysis. 展开更多
关键词 AKI EPIDEMIOLOGY Diagnosis evolution BRAZZAVILLE
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Spatial evolution and spatial production of traditional villages from "backward poverty villages" to "ecologically well-off villages": Experiences from the hinterland of national nature reserves in China
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作者 Zhang Yiyi LI Yangbing 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1100-1118,共19页
With the rapid urbanization process,the space of traditional villages in China is undergoing significant changes.Studying the spatial evolution of traditional villages is significant in promoting rural spatial transfo... With the rapid urbanization process,the space of traditional villages in China is undergoing significant changes.Studying the spatial evolution of traditional villages is significant in promoting rural spatial transformation and realizing rural revitalization and sustainable rural development.Based on the traceability analysis of spatial production theory,this paper constructed an analytical framework for the spatial production evolution of traditional villages,analyzed the spatial evolution process and characteristics of traditional villages by using buffer analysis,spatial syntax,and other research methods,and revealed the characteristics of the spatial production evolution of traditional villages and the driving mechanism.The results show that:(1)The village spatial formation and development follow the village life cycle theory and usually develop from embryonic villages to diversified and integrated villages;(2)The evolution of village spatial production is characterized by the diversity of material space,the sublimation of daily life space,and the integration of social system space and generalization of emotional space;(3)The evolution of village spatial production from backward and poor village to ecologically well-off village is influenced by a combination of factors;(4)The village has formed a spatial structure of"people-land-scape-culture-industry",realized comprehensive reconstruction and spatial reproduction.The study results reflect the spatial evolution characteristics of traditional villages in mountainous areas in a more comprehensive way,which helps to promote the protection and development of traditional villages in mountainous areas and,to a certain extent,provides a reference for the development of rural revitalization. 展开更多
关键词 Traditional villages Spatial production Spatial evolution Spatial reconstruction
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Initiatives to clarify mechanisms of hydrological evolution in human-influenced Yellow River Basin 被引量:2
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作者 Li-liang Ren Shan-shui Yuan +6 位作者 Xiao-li Yang Shan-hu Jiang Gui-bao Li Qiu-an Zhu Xiu-qin Fang Yi Liu Yi-qi Yan 《Water Science and Engineering》 EI CAS CSCD 2023年第2期117-121,共5页
Significant changes in water cycle elements/processes have created serious challenges to regional sustainability and high-quality development in the Yellow River Basin in China.It is necessary to investigate the impac... Significant changes in water cycle elements/processes have created serious challenges to regional sustainability and high-quality development in the Yellow River Basin in China.It is necessary to investigate the impacts of climate change and human activities on hydrological evolution and disaster risk from a holistic perspective of the basin.This study developed initiatives to clarify the mechanisms of hydrological evolution in the human-influenced Yellow River Basin.The proposed research method includes:(1)a tool to simulate multiple factors and a multi-scale water cycle using a grid-based spatiotemporal coupling approach,and(2)a new algorithm to separate the responses of the water cycle to climate change and human impacts,and de-couple the eco-environmental effects using artificial intelligence techniques.With this research framework,key breakthroughs are expected to be made in the understanding of the impacts of land cover change on the water cycle and blue/green water redirection.The outcomes of this research project are expected to provide theoretical support for ecological protection and water governance in the basin. 展开更多
关键词 Climate change Human activities Hydrological evolution Runoff change Yellow River Basin
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Mineralogical characteristics,metallurgical properties and phase structure evolution of Ca-rich hematite sintering 被引量:1
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作者 Lele Niu Zhengjian Liu +4 位作者 Jianliang Zhang Dawei Lan Sida Li Zhen Li Yaozu Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期303-313,共11页
In order to study the sintering characteristics of Ca-rich iron ore,chemical analysis,laser diffraction,scanning electron microscopy,XRD-Rietveld method,and micro-sintering were used to analyze the mineralogical prope... In order to study the sintering characteristics of Ca-rich iron ore,chemical analysis,laser diffraction,scanning electron microscopy,XRD-Rietveld method,and micro-sintering were used to analyze the mineralogical properties and sintering pot tests were used to study the sintering behavior.In addition,a grey correlation mathematical model was used to calculate and compare the comprehensive sintering performance under different calcium-rich iron ore contents.The results demonstrate that the Ca-rich iron ore has coarse grain size and strong self-fusing characteristics with Ca element in the form of calcite(CaCO_(3)) and the liquid phase produced by the self-fusing of the calcium-rich iron ore is well crystallized.Its application with a 20wt%content in sintering improves sinter productivity,reduces fuel consumption,enhances reduction index,and improves gas permeability in blast furnace by 0.45 t/(m^(2)·h),6.11 kg/t,6.17%,and 65.39 kPa·℃,respectively.The Ca-rich iron ore sintering can improve the calorific value of sintering flue gas compared with magnetite sintering,which is conducive to recovering heat for secondary use.As the content of the Ca-rich iron ore increases,sinter agglomeration shifts from localized liquid-phase bonding to a combination of localized liquid-phase bonding and iron oxide crystal connection.Based on an examination of the greater weight value of productivity with grey correlation analysis,the Ca-rich iron ore is beneficial for the comprehensive index of sintering in the range of 0-20wt%content.Therefore,it may be used in sintering with magnetite concentrates as the major ore species. 展开更多
关键词 calcium-rich iron ore mineralogical properties phase structure evolution flue gas heat grey relation analysis
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Mechanism of the Impact of Floods and Typhoons on the Morphological Evolution of the Yangtze Estuary
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作者 JIAO Jian DING Lei +4 位作者 HAN Yu-fang SUN Jie-ying YANG Xiao-yu HUANG Yu-ming DOU Xi-ping 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期447-457,共11页
In the last two decades,the Yangtze Estuary has undergone significant changes under the influence of reduced sediment inflow and estuary engineering.This study investigates the influence of floods and typhoons on sedi... In the last two decades,the Yangtze Estuary has undergone significant changes under the influence of reduced sediment inflow and estuary engineering.This study investigates the influence of floods and typhoons on sediment concentration and the morphological evolution of shoals and channels in the Yangtze Estuary.The analysis is conducted through the utilization of topographic data measured pre-and post-flood events and observations of hydro-sedimentary changes during typhoons.By using a generalized estuary mathematical model,this study examines the interplay between varying tidal ranges,tidal divisions,runoff volumes,and regulation projects on the erosion and deposition of shoals and channels in bifurcated estuaries.The results show that due to the implementation of river and waterway regulation projects,the impact of the 2020 flood on the main channel and shoal was significantly less than that of the1998 flood.The swing amplitude of the South Branch main channel decreased.However,local river sections such as the Southern Waterway of Baimao Shoal exhibited erosion.During typhoons,sediment concentration in the 20 cm above the bottom increased significantly and was closely related to wave processes,with a weakened correlation to tidal dynamics.After typhoons,high shoals in South Passage above 0 m were silted up,while the terrain on one side of the tail of Jiuduan Shoal in the downstream deep-water area was generally scoured due to strong wave action.The generalized mathematical model of the bifurcated estuary revealed that M2 tidal component contributed most to the ero sion and deposition evolution of estuary shoals and channels,with floods exhibiting characteristics of sedime ntation on shoals and erosion on channels.With the implementation of a branch rectification project,branch resistance increased,diversion decreased,and the riverbed changed from pre-project erosion to post-project sedimentation,with an increase in erosion in non-project branches. 展开更多
关键词 the Yangtze Estuary FLOOD TYPHOON morphological evolution
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Impacts of human activities on morphological evolution in the Modaomen Estuary, China
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作者 Tiehan Liao Haigang Zhan +1 位作者 Xing Wei Weikang Zhan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期79-92,共14页
The morphology of the Modaomen Estuary(ME)has undergone drastic changes in recent decades,and quantifying the contribution of human activities and natural processes is crucial for estuary management.Using Landsat imag... The morphology of the Modaomen Estuary(ME)has undergone drastic changes in recent decades,and quantifying the contribution of human activities and natural processes is crucial for estuary management.Using Landsat images,chart data,and hydrological and meteorological data,this study analyzed the evolution of the shoreline and subaqueous topography of the ME and attempted to quantify the extent of the contributions of human activities.The results show that local human activities dominated morphological evolution in some periods.From 1973 to 2003,the shoreline advanced rapidly seaward,resulting in approximately half of the water area being converted into land.Human activity is critical to this process,with the direct contribution of local land reclamation projects reaching more than 85%.After 2003,the shoreline remained relatively stable,probably due to a decrease in land reclamation projects.Regarding the evolution of subaqueous topography,the shoals in the estuary were heavily silted and gradually disappeared during 1983–2003,and the waterways narrowed and deepened.The average siltation rate decreased from 15.43 mm/a to-1.02 mm/a,indicating that the ME changed from sedimentation to slight erosion.By detecting variations of sediment load,we found that upstream human activities reduced river sediment,while downstream human activities significantly increased sediment input to the ME,leaving little change in the actual sediment input to the ME for a relatively long period.In addition,based on the empirical relationship between the sediment input and siltation rate,local human activities influenced the shift in the siltation state more than upstream and downstream human activities did.These findings suggest that more attention should be paid to local human activities to improve the estuarine management in the ME. 展开更多
关键词 Modaomen Estuary morphological evolution human activity quantitative analysis
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Ecological and hydrologic evolution history in the sensitive zone of both East Asian summer monsoon and Westerly since the Last Glacial Maximum
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作者 LI Yu PENG Si-min 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1266-1281,共16页
The Qilian Mountains,located in the northeastern Qinghai-Tibet Plateau,is a sensitive zone of both East Asian summer monsoon(EASM)and westerly winds(WW).The evolution history and driving mechanism of the ecosystem and... The Qilian Mountains,located in the northeastern Qinghai-Tibet Plateau,is a sensitive zone of both East Asian summer monsoon(EASM)and westerly winds(WW).The evolution history and driving mechanism of the ecosystem and hydrologic cycle in this region on long-term timescales have not yet been clarified.In this study,we comprehensively study the hydrologic and ecological evolution history in the sensitive zone since the Last Glacial Maximum(LGM)by integrating surface sediments,paleoclimate records,TraCE-21ka transient simulations,and PMIP3-CMIP5 multi-model simulation.Results show that hydrologic and ecological proxies from surface sediments are significantly different from west to east and mainly divided into three sections:the monsoonaffected region in the eastern Qilian Mountains,the intersection region in the central Qilian Mountains,and the westerly-affected region in the western Qilian Mountains.Meanwhile,paleo-ecological and paleohydrologic reconstructions from the surroundings uncover a synchronous climate evolution that the EASM mainly controls the eastern Qilian Mountains and penetrates the central Qilian Mountains in monsoon intensity maximum,while the WW dominates the central and western Qilian Mountains on both glacial-interglacial and millennial timescales.The simulation results further bear out the glacial humid climate in the central and western Qilian Mountains caused by the enhanced WW,and the humidity maximum in the eastern Qilian Mountains controlled by the strong mid-Holocene monsoon.In general,east-west differences in climate pattern and response for the EASM and the WW are integrally stable on both short-term and long-term timescales. 展开更多
关键词 EastAsian summer monsoon Westerly winds Last Glacial Maximum Ecological and hydrologic evolution history Qilian Mountains
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Etiological and Evolutionary Profile of Anemia in Patients Hospitalized in the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes
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作者 Sangaré Drissa Cissé Sékou Mamadou +7 位作者 Guindo Youssouf Abdoulaye Diawara Diakité Niagalé Boly Berthé Bréhima Keita Kaly Issa Diallo Traore Djenebou Soucko Kaya Assetou 《Open Journal of Internal Medicine》 CAS 2023年第1期51-61,共11页
Introduction: Anemia is one of the most common public health problems in the world and affects all ages. Objective: To describe the etiological and evolutionary profile of anemia in patients hospitalized in the Intern... Introduction: Anemia is one of the most common public health problems in the world and affects all ages. Objective: To describe the etiological and evolutionary profile of anemia in patients hospitalized in the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes. Methodology: It was a descriptive and cross-sectional study with retrospective data collection which took place from January 1 to December 31, 2020 at the Internal Medicine Unit of the Fousseyni Daou Hospital in Kayes. It covered all anemic patients hospitalized during the study period. Results: We identified 91 cases of anemia out of 200 patients admitted to the Unit that is a hospital prevalence of 45.5%. The age group of 26 to 35 years was the most represented, that is to say 29 cases (31.87%) with an average age of 43.55 years ± 17.48 years, the female sex predominated, 51 cases (56.04%) with a sex ratio of 0.78. Housewives represented 41 cases (45.05%). The majority of patients resided in rural areas 48 cases (52.75%). The main manifestations were: asthenia 75 cases (78.02%), vertigo 68 cases (74.72%), dyspnea 62 cases (68.13%), headaches 59 cases (64.83%), palpitations 55 cases (60.44%), conjunctival pallor 53 cases (58.24%), tachycardia 43 cases (47.25%), systolic murmur 18 cases (19.78%) and IMO 11 cases (12.09%). The associated pathologies were: infected diabetic wounds 25.27%, followed by bacterial pleuro-pneumopathy 18.68%. Biologically, microcytic anemia was the most frequent 49 cases (53.84%), followed by normocytic anemia 35 cases (38.46%) and macrocytic anemia 7 cases (7.7%). Anemia was hypochromic, 53 cases (58.24%) were more encountered compared to normochromic anemia 38 cases (41.76%). The anemia was: severe in 43 cases (47.25%), moderate 29 cases (31.87%) and mild 19 cases (20.88%). Inflammatory anemia is the most common etiological diagnosis in 60% of cases, followed by vitamin B12 deficiency anemia observed in 21% of patients and then blood diseases in 7.33% of cases. The main causes of death were HIV (50%) and kidney failure (33.33%). Conclusion: Anemia is a frequent symptom in internal medicine. It constitutes a real diagnostic challenge for the internist and this sometimes in an emergency context. The use of specialized examinations and labile blood products is essential in our hospital. 展开更多
关键词 ANEMIA ETIOLOGY evolution Internal Medicine Fousseyni Daou Hospital Kayes MALI
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Evolution of HBV Viral Load during Clinical and Biological Follow-Up of Chronic Hepatitis B Patients at the Saint Camille Hospital in Ouagadougou
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作者 Théodora Mahoukèdè Zohoncon T. Rose Clémence Ido Da +5 位作者 Nicaise Zagre Pauline Belemkoabga Denise P. Ilboudo Abdoul Karim Ouattara Paul Ouedraogo Jacques Simpore 《Advances in Infectious Diseases》 2023年第4期550-563,共14页
Hepatitis B virus (HBV) infection is a major public health problem worldwide. The aim of this study was to document the dynamics of HBV viral load during the follow-up of chronic hepatitis B patients at the Saint Cami... Hepatitis B virus (HBV) infection is a major public health problem worldwide. The aim of this study was to document the dynamics of HBV viral load during the follow-up of chronic hepatitis B patients at the Saint Camille Hospital in Ouagadougou (HOSCO) from 2017 to 2021. This descriptive retrospective study was carried out in the Hepato-Gastro-Enterology Department of HOSCO and focused on patients who were undergoing treatment for chronic viral hepatitis B. A total of 260 cases of chronic hepatitis B were included in the study. The most affected age group was 21 to 30 years, accounting for 48.08% of the cases. Lifestyle factors included alcohol consumption (3.08%) and tobacco use (2.69%). Major risk factors for transmission included lack of vaccination (98.46%), family history of HBV infection (68.00%) and engagement in high-risk activities (28.00%). Patients requiring treatment were prescribed Tenofovir 300 mg tablets. FibroScan<sup>®</sup> showed the presence of stage F3-F4 fibrosis (2.14%) and S3 steatosis (13.33%). After one year of follow-up, 6.92% of patients achieved an undetectable viral load with normalized transaminase levels. The majority of other patients had a detectable viral load but below 20,000 IU/mL. The prevalence of viral hepatitis B remains significant worldwide. Although effective and well-monitored treatment can lead to undetectable viremia, prevention remains the most effective strategy for successful management of this disease. 展开更多
关键词 Chronic Viral Hepatitis B Viral DNA FOLLOW-UP evolution of Viral Load
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Structural attributes,evolution and petroleum geological significances of the Tongnan negative structure in the central Sichuan Basin,SW China
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作者 TIAN Fanglei WU Furong +6 位作者 HE Dengfa ZHAO Xiaohui LIU Huan ZHANG Qiaoyi LE Jinbo CHEN Jingyu LU Guo 《Petroleum Exploration and Development》 SCIE 2023年第5期1120-1136,共17页
The Tongnan secondary negative structure in central Sichuan Basin has controls and influences on the structural framework and petroleum geological conditions in the Gaoshiti-Moxi area.To clarify the controls and influ... The Tongnan secondary negative structure in central Sichuan Basin has controls and influences on the structural framework and petroleum geological conditions in the Gaoshiti-Moxi area.To clarify the controls and influences,the deformation characteristics,structural attributes and evolution process of the Tongnan negative structure were investigated through a series of qualitative and quantitative methods such as balanced profile restoration,area-depth-strain(ADS)analysis,and structural geometric forward numerical simulation,after comprehensive structural interpretation of high-precision 3D seismic data.The results are obtained in three aspects.First,above and below the P/AnP(Permian/pre-Permian)unconformity,the Tongnan negative structure demonstrates vertical differential structural deformation.It experiences two stages of structural stacking and reworking:extensional depression(from the Sinian Dengying Formation to the Permian),and compressional syncline deformation(after the Jurassic).The multi-phase trishear deformation of the preexisting deep normal faults dominated the extensional depression.The primary depression episodes occurred in the periods from the end of Late Proterozoic to the deposition of the 1st–2nd members of the Dengying Formation,and from the deposition of Lower Cambrian Longwangmiao Formation–Middle–Upper Cambrian until the Ordovician.Second,the multi-stage evolution process of the Tongnan negative structure controlled the oil and gas migration and adjustment and present-day differential gas and water distribution between the Tongnan negative structure and the Gaoshiti and Moxi-Longnüsi structural highs.Third,the Ordovician,which is limitedly distributed in the Tongnan negative structure and is truncated by the P/AnP unconformity on the top,has basic geological conditions for the formation of weathering karst carbonate reservoirs.It is a new petroleum target deserving attention. 展开更多
关键词 structural attribute structural evolution Sinian Dengying Formation oil and gas negative structure Gaoshiti-Moxi area Sichuan Basin
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Identification, evolution and geological indications of solid bitumen in shales: A case study of the first member of Cretaceous Qingshankou Formation in Songliao Basin, NE China
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作者 LIU Bo WANG Liu +4 位作者 FU Xiaofei HUO Qiuli BAI Longhui LYU Jiancai WANG Boyang 《Petroleum Exploration and Development》 SCIE 2023年第6期1345-1357,共13页
On the basis of sorting out current understanding of solid bitumen (SB) in shales and taking organic-rich shales in the first member of the Cretaceous Qingshankou Formation in the Songliao Basin as an example, the def... On the basis of sorting out current understanding of solid bitumen (SB) in shales and taking organic-rich shales in the first member of the Cretaceous Qingshankou Formation in the Songliao Basin as an example, the definition, classification, occurrence and evolution path of SB are systemtically studied, and the indicative significance of SB reflectance (Rob) on maturity and its influence on the development of reservoir space are discussed and summarized. The results show that the difference of primary maceral types is primarily responsible for the different evolution paths of SB. Most of the pre-oil bitumen is in-situ SB with only a small amount being of migrated SB, while most of the post-oil bitumen and pyrobitumen are migrated SB. From the immature to early oil maturity stage, bituminite, vitrinite, and inertinite can be distinguished from SB based on their optical characteristics under reflected light, and alginite can be differentiated from SB by their fluorescence characteristics. Under scanning electron microscope, in-situ SB and migrated SB can be effectively identified. Rob increases linearly with increasing vitrinite reflectance (Ro), as a result of a decrease of aliphatic structure and the enhancement of aromatization of SB. Within the oil window three types of secondary pores may develop in SB, including modified mineral pores, devolatilization cracks and bubble holes. At a high maturity stage spongy pores may develop in pyrobitumen. Scanning electron microscopy combined with in-situ SEM-Raman spectroscopy can further reveal the structral information of different types of SB, thus providing crucial data for understanding for understanding OM migration paths, dynamics, and distances at micro-scale. 展开更多
关键词 shale solid bitumen reflectance primary maceral difference solid bitumen evolution path reservoir space Songliao Basin Cretaceous Qingshankou Formation
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Dynamical characteristics of geomorphologic evolution of the basins covered by Pisha-sandstone in the eastern wing of the Ordos Plateau, China 被引量:4
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作者 GU Zhen-kui SHI Chang-xing 《Journal of Mountain Science》 SCIE CSCD 2018年第5期1046-1056,共11页
There are several basins with high sediment yield in the Pisha-sandstone covering area of the east wing of the Ordos Plateau. Due to the lack of targeted research on the dynamical characteristics of geomorphic evoluti... There are several basins with high sediment yield in the Pisha-sandstone covering area of the east wing of the Ordos Plateau. Due to the lack of targeted research on the dynamical characteristics of geomorphic evolution that plays an important role in the sand production, this paper analyzed the tectonic activity intensity and erosion characteristics of the area. The results show that the intensity of tectonic activities in the area is generally moderateweak and shows an unconspicuous increase from north to south. Tectonic activity is manifested mainly in the form of uplift. The uplift rate in the lower reaches of each basin is greater than the erosion rate,which is prominent in the Kuyehe and the Tuweihe rivers. During the uplift of the regional topography,the most serious parts under erosion are generally concentrated in the upstream and midstream of basins. All longitudinal profiles of the basins have a shape close to an exponential function, which indicates that they are in the early stage of erosion evolution. The mechanisms of geomorphologic evolution of these basins have a great similarity. The conservative estimate of historical average erosion rate was less than 182–520 t/(km^2·yr), much less than that of the modern times. The average stream power values are typically distributed between 4 and102 W/m, with the larger being in the Kuyehe and the Tuweihe rivers and the smallest being in the Qinshuihe River. The maximum stream power value appears in the downstream reach, which should be the main reason for the particles being directly injected into the Yellow River. From the perspective of geomorphological evolution, the current soil and water conservation measures can hardly cure the erosion of these basins in the long run. 展开更多
关键词 Dynamic characteristics Geomorphologic evolution ORDOS PLATEAU Tectonicactivity Stream power Geomorphological parameter
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Simulation of methane adsorption in diverse organic pores in shale reservoirs with multi-period geological evolution 被引量:3
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作者 Shangbin Chen Chu Zhang +2 位作者 Xueyuan Li Yingkun Zhang Xiaoqi Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第5期844-855,共12页
In shale reservoirs,the organic pores with various structures formed during the thermal evolution of organic matter are the main storage site for adsorbed methane.However,in the process of thermal evolution,the adsorp... In shale reservoirs,the organic pores with various structures formed during the thermal evolution of organic matter are the main storage site for adsorbed methane.However,in the process of thermal evolution,the adsorption characteristics of methane in multi type and multi-scale organic matter pores have not been sufficiently studied.In this study,the molecular simulation method was used to study the adsorption characteristics of methane based on the geological conditions of Longmaxi Formation shale reservoir in Sichuan Basin,China.The results show that the characteristics of pore structure will affect the methane adsorption characteristics.The adsorption capacity of slit-pores for methane is much higher than that of cylindrical pores.The groove space inside the pore will change the density distribution of methane molecules in the pore,greatly improve the adsorption capacity of the pore,and increase the pressure sensitivity of the adsorption process.Although the variation of methane adsorption characteristics of different shapes is not consistent with pore size,all pores have the strongest methane adsorption capacity when the pore size is about 2 nm.In addition,the changes of temperature and pressure during the thermal evolution are also important factors to control the methane adsorption characteristics.The pore adsorption capacity first increases and then decreases with the increase of pressure,and increases with the increase of temperature.In the early stage of thermal evolution,pore adsorption capacity is strong and pressure sensitivity is weak;while in the late stage,it is on the contrary. 展开更多
关键词 Adsorption mechanism Shale reservoir Diverse pores Multi-period geological evolution Thermal evolution
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The response between glacier evolution and eco-geological environment on the Qinghai-Tibet Plateau 被引量:3
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作者 Xi-yong Sun Rui-jiang Zhang +4 位作者 Wei Huang Ang Sun Liang-jun Lin Hong-gen Xu De-cai Jiang 《China Geology》 2019年第1期1-7,共7页
Based on the remote sensing survey and monitoring results of snow lines on the Qinghai-Tibet Plateau, the authors analyzed the following eco-geological factors such as water resources, permafrost, desertification, wet... Based on the remote sensing survey and monitoring results of snow lines on the Qinghai-Tibet Plateau, the authors analyzed the following eco-geological factors such as water resources, permafrost, desertification, wetlands, lake, geological disasters, sea-level rising, earthquake, etc., affected by the change of snow lines over the past 40 years, and discuss the response between glacier evolution and the eco-geological environment preliminarily. 展开更多
关键词 Qinghai-Tibet Plateau GLACIER evolution Ecological ENVIRONMENT GEOlogicAL ENVIRONMENT RESPONSE
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Impact of the cord-grass Spartina alterniflora on sedimentary and morphological evolution of tidal salt marshes on the Jiangsu coast,China 被引量:15
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作者 WANG Aijun GAO Shu JIA Jianjun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第4期32-42,共11页
The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is hi... The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick - Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick - Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the iatroduction of S. alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S. alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area. 展开更多
关键词 Spartina alterniflora tidal flat SEDIMENTATION morphological evolution Jiangsu coast
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Design Around Bundle Patent Portfolio Based on Technological Evolution 被引量:6
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作者 Hui Li Jiefeng Yuan +1 位作者 Runhua Tan Qingjin Peng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第5期34-49,共16页
Product innovation can be achieved by analyzing leading products patents in the market.Different methods have been proposed for design around patent,commonly using the elimination or replacement of a single patent ele... Product innovation can be achieved by analyzing leading products patents in the market.Different methods have been proposed for design around patent,commonly using the elimination or replacement of a single patent element However,the existing research fails to restore the position and function of the design around object in the original patent portfolio of enterprises,which often leads to the phenomenon of evading one patent and violating another.This paper proposes a method for design around patent through using the fusion of technologies of the evolution theory and bundle-type patent portfolio analysis in the initial stage of product development.The object system is analyzed to select technical opportunities through the evolutionary path of technologies and functional trimming methods to achieve circumvent barriers of bundle-type patents.The bundle patent portfolio is analyzed for the product evolution with a radar map.The technological evolution path is combined with the TRIZ innovation method to identify and solve the design problem.Patentability of the new design is evaluated using the patent system rules for innovative scheme difference from the original patent portfolio.The method is verified in a case study for the design of a glass-wiping robot.The design solution has been patented. 展开更多
关键词 Design AROUND PATENT BUNDLE PATENT PORTFOLIO TRIZ TECHNOlogicAL evolution Inventive problem solving
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Phases of Environmental Evolution Indicated by Primary Chemical Elements and Paleontological Records in the Upper Pleistocene-Holocene Series for the Salawusu River Valley,China 被引量:17
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作者 LI Baosheng WEN Xiaohao +5 位作者 QIU Shifan David Dian ZHANG DU Shuhuan CHEN Deniu OU Xianjiao NIU Dongfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第4期555-565,共11页
Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section ... Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section in China's Salawnsu River valley into six segments: MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6. The boundary ages for MGS1 (the Dishaogouwan and Dagouwan Formations), MGS2 (the upper Chengchuan Formation), MGS3 (the middle Chengchuan Formation), MGS4 (the lower Chengchuan Formation), MGS5 (most strata of the Salawusu Formation) and MGS6 (the bottom of the Salawusu Formation and the top of the Lishi Formation) correspond to those of MIS1, MIS2, MIS3, MIS4, MISS and MIS6, respectively, from deep sea sediments or continental glaciers. MGS5 can be subdivided into five subsegments (MGS5a, MGS5b, MGS5c, MGS5d and MGS5e) and the boundary ages of these subsegments correspond to those of MISSa, MISSb, MIS5c, MIS5d and MIS5e, respectively. Based on the paleoenvironment and paleoecology indicated by the primary chemical elements, fossil vertebrates, mollusks and pollen grains, we hypothesize that MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6 and the subsegments of MGS5 match the corresponding stages for oxygen isotopes in the deep sea sediments and continental glaciers, and the substages of MIS5 in terms of climatic characters, further explaining the phenomena that determined the formation of the late Quaternary strata and the paleontology of the Salawusu River valley. These phenomena relate to fluctuations in the global climate (and particularly in the East Asian monsoon) during the glacial and interglacial periods. 展开更多
关键词 Salawusu River valley Upper Pleistocene-Holocene Series primary chemical elements phases of evolution paleontological records
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Spatio-temporal evolution of ecologically-sustainable land use in China's Loess Plateau and detection of its influencing factors 被引量:5
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作者 QU Lu-lu LIU Yan-sui CHEN Zong-feng 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1065-1074,共10页
Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to surv... Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment. 展开更多
关键词 Ecologically-sustainable LAND use SPATIO-TEMPORAL evolution influencing factor Population migration LOESS PLATEAU
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