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Identification indexes and diagrams for natural gas origin:Connotation,significance and application
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作者 PENG Ping'an HOU Dujie +8 位作者 TENGER NI Yunyan GONG Deyu WU Xiaoqi FENG Ziqi HU Guoyi HUANG Shipeng YU Cong LIAO Fengrong 《Petroleum Exploration and Development》 2025年第3期573-586,共14页
Accurate identification of natural gas origin is fundamental to the theoretical research on natural gas geosciences and the exploration deployment and resource potential assessment of oil and gas.Since the 1970s,Acade... Accurate identification of natural gas origin is fundamental to the theoretical research on natural gas geosciences and the exploration deployment and resource potential assessment of oil and gas.Since the 1970s,Academician Dai Jinxing has developed a comprehensive system for natural gas origin determination,grounded in geochemical theory and practice,and based on the integrated analysis of stable isotopic compositions,molecular composition,light hydrocarbon fingerprints,and geological context.This paper systematically reviews the core framework established by him and his team according to related references and application results,focusing on the conceptual design and technical pathways of key diagnostic diagrams such asδ^(13)C_(1)-C_(1)/(C_(2)+C_(3)),δ^(13)C_(1)-δ^(13)C_(2)-δ^(13)C_(3),δ^(13)CCO_(2)versus CO_(2)content,and the C7light hydrocarbon ternary plot.We evaluate the applicability and innovation of these tools in distinguishing between oil-type gas,coal-derived gas,microbial gas,and abiogenic gas,as well as in identifying mixed-source gases and multi-stage charging systems.The findings suggest that this identification system has significantly advanced natural gas geochemical interpretation in China,shifting from single-indicator analyses to multi-parameter integration and from qualitative assessments to systematic graphical identification,and has also exerted considerable influence on international research in natural gas geochemistry.The structured overview of the development trajectory of natural gas origin discrimination methodologies provides a technical support for natural gas geological theory and practice and offers a scientific foundation for the academic evaluation and application of related achievements. 展开更多
关键词 natural gas natural gas geochemistry origin identification identification index identification diagram coal-derivedgas inorganic origin
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使用DRS origin软件建立HPLC替代对照品法测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量
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作者 孔德娟 左甜甜 +5 位作者 盛雪 嵇增云 邹广鑫 田佳勋 王艳楠 闫凤杰 《中国新药杂志》 北大核心 2025年第21期2316-2325,共10页
目的:建立双标多测法(TRSDMC)同时测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量,节约对照品同时更全面地控制该品种的质量。方法:采用HPLC法测定,使用C 18色谱柱;流动相为乙腈(A)-0.1%甲酸水(B),流速1.0 mL·... 目的:建立双标多测法(TRSDMC)同时测定防风中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷的含量,节约对照品同时更全面地控制该品种的质量。方法:采用HPLC法测定,使用C 18色谱柱;流动相为乙腈(A)-0.1%甲酸水(B),流速1.0 mL·min^(-1),梯度洗脱;柱温35℃;检测波长254 nm;进样体积10μL。以升麻素苷和5-O-甲基维斯阿米醇苷为对照,使用DRS origin软件进行双标线性校正预测特征峰的保留时间,并通过替代对照品法获得相对校正因子,计算结果与外标法进行比较。结果:通过DRS origin软件拟合的标准曲线预测待测化合物准确,并结合校正因子计算所得含量与外标法测定结果比较,绝对偏差均<0.2 mg·g^(-1),准确度均大于95.0%。24批次样品中升麻素苷、升麻素、5-O-甲基维斯阿米醇苷、亥茅酚苷含量范围分别为0.8399~3.7996、0.0206~0.1718、0.6773~2.5099、0.0457~0.2032 mg·g^(-1)。结论:双标线性校正预测保留时间与相对保留时间法相比,前者保留时间预测结果准确度高,色谱柱的适用范围广,为防风多指标含量测定提供了新的思路和方法。 展开更多
关键词 防风 升麻素苷 升麻素 5-O-甲基维斯阿米醇苷 亥茅酚苷 替代对照品法 DRS origin软件
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基于phyphox和Origin软件的牛顿第二定律实验研究
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作者 邹兆轩 伏森泉 +4 位作者 丁益民 程文睿 刘沁 苏鹏 陈九江 《物理通报》 2025年第5期90-93,97,共5页
借助phyphox和Origin软件,利用手机或平板这种自带深度传感器的现代技术设备,对牛顿第二定律的实验进行优化与创新,并将实验数值与理论数值进行对比,实验结果准确地验证了牛顿第二定律的准确性.这样的实验方法在提高实验教学的可视化程... 借助phyphox和Origin软件,利用手机或平板这种自带深度传感器的现代技术设备,对牛顿第二定律的实验进行优化与创新,并将实验数值与理论数值进行对比,实验结果准确地验证了牛顿第二定律的准确性.这样的实验方法在提高实验教学的可视化程度和可操作性的同时,还有利于培养学生处理和分析图像的能力,发展学生核心素养. 展开更多
关键词 phyphox origin 牛顿第二定律 中学物理
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An Analysis about the Origin and Essence of Mass Based on Particle-Propagating Model and Wave Equations of Scalar Waves 被引量:1
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作者 Jiang Jian-zhong Chen Xi-qi 《Journal of Environmental Science and Engineering(B)》 2025年第2期65-75,共11页
If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at ligh... If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at light speed.Based on this spatial motion hypothesis,we derive a unified field equation and a set of Maxwell’s equations for vacuum SWs(Scalar Waves)generating a huge spiral force field that drives the energy to spiral inwardly and distort,leading to the formation of mass.Furthermore,they also uncover that mass is fundamentally an ultimate expression of energy,manifesting as the result of spiral motion of space at light speed.And then,we indirectly validate the theory that coherent light waves’collision generate SWs and subsequently mass through the experiment verifying the Breit-Wheeler process.The establishment of our theory offers a new analytical tool for the exploration of mass origin,the cosmic Big Bang,unified field theories. 展开更多
关键词 QED(Quantum Electrodynamics) SW mass origin unified field theories
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Deciphering origins of hydrocarbon deposits by means of intramolecular carbon isotopes of propane adsorbed on sediments 被引量:1
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作者 Peng Liu Xiao-Feng Wang +6 位作者 Jie Wang Juske Horita Zhi-Yong Wang Ying Lin Rui-Liang Guo Fu-Qi Li Wen-Hui Liu 《Petroleum Science》 2025年第2期546-556,共11页
Hydrocarbons are one of the important fluids within the Earth's crust,and different biotic and abitoic processes can generate hydrocarbon during geological periods.Tracing the sources and sinks of hydrocarbons can... Hydrocarbons are one of the important fluids within the Earth's crust,and different biotic and abitoic processes can generate hydrocarbon during geological periods.Tracing the sources and sinks of hydrocarbons can help us better understand the carbon cycle of the earth.In this study,an improved approach of adsorbed hydrocarbons extraction from sediments was established.The improved thermal desorption approach,compound-specific isotope analysis and position-specific isotope analysis were integrated to investigate the molecular and intramolecular isotope fractionation between trace hydrocarbon gases within sediments and geological hydrocarbon deposits.The isotopic compositions of the terminal position carbon of propane(δ^(13)C_(terminal))serves as a correlation indicator between trace hydrocarbon gases within sediments and geological hydrocarbon deposits.The tight sandstone gas from the Turpan-Hami Basin is a first case study for the application of this novel method to trace hydrocarbon origins.The results showed that the hydrocarbons in the tight sandstone gases in the study area most likely originated from humic organic matter(typeⅢkerogen)at an early mature stage.δ^(13)C_(terminal)values of the thermally desorbed propane gases from different source rocks were distinguishable and the values of the tight sandstone gases significantly overlap with those of the Lower Jurassic Sangonghe source rocks,suggesting their genetic relationship.Overall,the results provided novel position-specific carbon isotopic constraints on origins of hydrocarbons. 展开更多
关键词 Hydrocarbon origins Intramolecular isotope distributions Position-specific isotope analysis(PSIA) PROPANE
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巧用Origin软件构建种群密度数学模型——以“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”为例
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作者 薛丽华 《中学生物教学》 2025年第9期62-64,共3页
在高中生物学教学中,数学模型的构建可以利用Origin软件来处理数据,得到直观的拟合图像。在“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”中,利用Origin软件进行数据的线性拟合,得到了单次捕获数目(y)和累积捕获数目(x)的线性拟... 在高中生物学教学中,数学模型的构建可以利用Origin软件来处理数据,得到直观的拟合图像。在“黑光灯诱捕法调查封闭环境中某种昆虫种群密度实验”中,利用Origin软件进行数据的线性拟合,得到了单次捕获数目(y)和累积捕获数目(x)的线性拟合数学模型,简单明了地推测出种群数量估算值,计算出种群密度。 展开更多
关键词 数学模型 origin软件 线性拟合
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Origin拟合方法在课程教学中的研究和应用
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作者 胡吉玉 姚昌明 +1 位作者 訾振发 刘超成 《广州化工》 2025年第6期204-206,共3页
为了提升数据处理方法对于课程教学的影响,加深学生对于课程教学中所遇到的理论知识概念有更深刻地研究和掌握,最后能够将理论知识和数据处理应用在一起,最终实现学以致用,既理论与实践相结合、互相促进的教学方法和学习方式。在本论文... 为了提升数据处理方法对于课程教学的影响,加深学生对于课程教学中所遇到的理论知识概念有更深刻地研究和掌握,最后能够将理论知识和数据处理应用在一起,最终实现学以致用,既理论与实践相结合、互相促进的教学方法和学习方式。在本论文中以Origin拟合数据为例,处理在课程教学和学习中遇到的知识点和概念性结论,使得学生的学习更加直观、逻辑更加清晰,与此同时,也能够锻炼学生将理论转为实际的学习和操作能力,达到提升教学效果的目的。 展开更多
关键词 origin 拟合方法 课程教学
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Origin软件在物理化学实验中的应用
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作者 龚书生 余丽丽 +1 位作者 吴菊 杨梅 《山东化工》 2025年第12期162-165,共4页
在物理化学实验中数据处理是实验的重要体现,而数据处理有多种方式,其中Origin作为一个科学绘图、数据分析软件,能够快速准确地处理实验数据,得到所需要的实验结果。以几个物理化学实验的为例,将Origin软件的数据处理后的结果与其他几... 在物理化学实验中数据处理是实验的重要体现,而数据处理有多种方式,其中Origin作为一个科学绘图、数据分析软件,能够快速准确地处理实验数据,得到所需要的实验结果。以几个物理化学实验的为例,将Origin软件的数据处理后的结果与其他几种数据处理方式得到结果进行对比,发现Origin软件在数据绘图、拟合等方面具有优势。 展开更多
关键词 origin软件 物理化学实验 数据处理
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Research Advances in the Control of Spider Mites Using Bioactive Substances of Biological Origin
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作者 Tongshu DAI Kaicheng LIU Yanjie LUO 《Asian Agricultural Research》 2025年第11期51-53,共3页
Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to th... Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development. 展开更多
关键词 Bioactive substances of BIOLOGICAL origin Spider MITE CONTROL RNA interference Plant-derived ACTIVE substances Microorganism-derived ACTIVE substances
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Fatigue damage origin of laser direct energy deposited titanium alloy:Competition and combination of gas pore and microstructure
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作者 Jun CAO Xiangyi KONG +2 位作者 Yanyan ZHU Shuquan ZHANG Jikui ZHANG 《Chinese Journal of Aeronautics》 2025年第4期321-332,共12页
To accurately predict the fatigue properties of additively manufactured(AM)titanium alloys,it is important to understand the fatigue damage origin behavior.However,this behavior is still ambiguous.Therefore,the effect... To accurately predict the fatigue properties of additively manufactured(AM)titanium alloys,it is important to understand the fatigue damage origin behavior.However,this behavior is still ambiguous.Therefore,the effects of internal defects and microstructures on the fatigue damage origin behavior of laser direct energy deposited TC11(LDED-TC11)alloy were investigated using a fatigue origin criterion.The criterion was proposed to analyze the competing and combining effects by coupling the plasticity-corrected crack driving force,the resistance of short cracks,and the modified Kitagawa-Takahashi diagram.Three scenarios corresponding to the criterion were clarified,representing the damage mechanisms dominated by the microstructure,the combined effect of internal defect and microstructure,and the internal defect.As a result,the fatigue fracture morphology of high-cycle fatigue tests demonstrates two fatigue origin modes,i.e.microstructure and gas pore origin modes.The two fatigue modes belong to Scenario I and Scenario II,respectively,which indicates that the fatigue damage origin process of this alloy is sensitive to microstructure.Besides,it was found that the width of the primary a phase of this alloy is strongly relevant to intrinsic defect size.Finally,the fatigue origin criterion was verified in three aspects. 展开更多
关键词 Additive manufacture High-cycle fatigue Fatigue origin criterion Fatigue damage Gas pore MICROSTRUCTURE
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Diagnostic utility of sepsis screening tools,procalcitonin,and Creactive protein in nosocomial fever of unknown origin
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作者 Shashikant Saini Sapna Pahil +3 位作者 Ritin Mohindra Naresh Sachdeva Navneet Sharma Ashok K Pannu 《World Journal of Critical Care Medicine》 2025年第3期251-262,共12页
BACKGROUND Nosocomial fever of unknown origin(nFUO)is a frequent and challenging diagnostic entity,encompassing diverse infectious and non-infectious etiologies.Timely identification is crucial,yet evidence on the dia... BACKGROUND Nosocomial fever of unknown origin(nFUO)is a frequent and challenging diagnostic entity,encompassing diverse infectious and non-infectious etiologies.Timely identification is crucial,yet evidence on the diagnostic accuracy of commonly employed sepsis screening tools and biomarkers remains sparse.We hypothesized that these tools and biomarkers measured at fever onset could distinguish infectious from non-infectious causes of nFUO in critically ill adults.AIM To evaluate the diagnostic utility of sepsis tools and biomarkers in identifying infectious causes of nFUO.METHODS This prospective observational study included patients admitted to the Acute Care Emergency Medicine Unit,Postgraduate Institute of Medical Education and Research,Chandigarh,India(July 2023 to December 2024).nFUO was defined by Durack and Street criteria.Diagnostic performance of sepsis screening tools(systemic inflammatory response syndrome,Sequential Organ Failure Assessment,quick Sequential Organ Failure Assessment,National Early Warning Score,and Modified Early Warning Score)and biomarkers[procalcitonin(PCT),C-reactive protein(CRP)]at fever onset was assessed using receiver operating characteristic curve analysis.RESULTS Of 80 cases(mean age 42.9±16.5 years;80% male),42.5% had infectious causes,38.7% non-infectious,and 18.8% remained undiagnosed.Pneumonia(26.2%)and bloodstream infections(11.2%)were the most common infectious etiologies,while central fever and thrombophlebitis(each 7.5%)were predominant among non-infectious causes.Sepsis tools showed poor diagnostic accuracy,with area under the receiver operating characteristic curve(AUC)values close to 0.5.PCT demonstrated modest performance(AUC=0.61;optimal cut-off:0.85μg/L),while CRP was paradoxically higher in non-infectious cases(AUC=0.45).Overall mortality was 20% and was highest among undiagnosed patients(33.3%).Fever duration and hospitalization length were significantly greater in infectious cases.CONCLUSION Sepsis tools,PCT,and CRP have limited utility in identifying infectious causes of nFUO in critically ill adults and should not solely guide initial decision-making. 展开更多
关键词 Critical care Fever of unknown origin NOSOCOMIAL SEPSIS Screening tools PROCALCITONIN C-reactive protein
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Evaluating fever of unknown origin definitions in a tertiary care setting:Implications for diagnostic criteria revision
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作者 Pathik Dhangar Prasan Kumar Panda +6 位作者 Ravi Kant Rohit Gupta Ruchi Dua Ashutosh Tiwari Sandeep Saini Kavita Khoiwal Yogesh Bahurupi 《World Journal of Experimental Medicine》 2025年第2期103-108,共6页
BACKGROUND Fever of unknown origin(FUO)remains a diagnostic challenge and was originally defined in 1961.Its classic criteria include fever≥38.3°C(≥101°F)on multiple occasions,fever lasting three weeks or ... BACKGROUND Fever of unknown origin(FUO)remains a diagnostic challenge and was originally defined in 1961.Its classic criteria include fever≥38.3°C(≥101°F)on multiple occasions,fever lasting three weeks or longer,and a diagnosis after one week of inpatient evaluation.However,these criteria may not fully encompass the varied clinical presentations seen in resource-limited settings such as India.The adaptation of FUO definitions to local healthcare contexts is crucial for enhancing diagnostic accuracy and optimizing patient outcomes.AIM To investigate the applicability of revised FUO criteria in a tertiary care setting in India.METHODS This longitudinal-exploratory study at All India Institute of Medical Sciences Rishikesh(January 2018–December 2022)analyzed 228 adult patients with fever≥99.1°F lasting over three days.Patients diagnosed within three days of admission were excluded.Data were collected retrospectively and prospectively using predefined FUO definitions based on durations of nondiagnosis(3-21 days,>21 days),temperature ranges(99.1°F-100.9°F,≥101°F),and hospitalization durations(3-7 days,>7 days).Descriptive statistics and comparative tests(Fisher's exact test,χ2 test)evaluated outcomes across definitions.RESULTS Among the proposed FUO definitions,Definition B(fever lasting 3-21 days,temperatures between 99.1°F-100.9°F,hospitalization>7 days)predominated(40.8%),while only 2.2%met the classical criteria.Notably,36.5%of Definition B patients remained undiagnosed after 7-10 days,despite 94%undergoing diagnostic workups within 21 days.Infection emerged as the leading etiology across definitions,without significant variation in outcomes or mortality during hospitalization(χ2=27.937,P=0.142).CONCLUSION Adapting FUO criteria to local contexts improves diagnostic accuracy and treatment.Definition B(40.8%prevalence)showed practical utility,with higher mortality in patients discharged on empirical'Anti-tuberculosis therapy'. 展开更多
关键词 Empirical therapy New definition Pyrexia of unknown origin TUBERCULOSIS
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基于Origin的工科本科生科研能力培养与教育创新模式构建
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作者 赵香园 王丽婷 +1 位作者 吴韦 任亚琦 《中文科技期刊数据库(全文版)教育科学》 2025年第1期039-042,共4页
Origin工具在工科本科生科研能力培养中的融入具有极其深远的意义和影响,也是促进教育模式创新的关键一环。Origin工具是一款强大的数据分析和绘图工具,能够有效实现数据的可视化,在激发学生学习热情的同时也能满足学生实际学习需求,强... Origin工具在工科本科生科研能力培养中的融入具有极其深远的意义和影响,也是促进教育模式创新的关键一环。Origin工具是一款强大的数据分析和绘图工具,能够有效实现数据的可视化,在激发学生学习热情的同时也能满足学生实际学习需求,强化教育的质量和成效。所以,论文围绕Origin工具在工科本科生科研能力培养中的融入进行了深层次的探索和研究,并且提出了推动工科本科生科研能力培养教育模式的创新对策,用以助力提升工科本科生人才培养质量,满足我国社会科学技术发展对于优秀人才的需求。 展开更多
关键词 origin工具 工科本科生 科研能力培养 教育创新
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The Origin of Engraving and Printing in the Field of Media Evolution Theory “The Early Tang Said” Challenge
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作者 LI Zhenggeng NIU Ruonan 《Cultural and Religious Studies》 2025年第4期170-178,共9页
The origin of engraving and printing has a variety of points of view,especially the“early Tang Dynasty”has the most far-reaching impact.Based on media evolution theory,engraved printing as a new media technology is ... The origin of engraving and printing has a variety of points of view,especially the“early Tang Dynasty”has the most far-reaching impact.Based on media evolution theory,engraved printing as a new media technology is first used in secular culture,folk entertainment,and other fields,after a long period of development,the new medium was accepted by the ruling class,the mainstream society;the use of the media began to intervene in the real society.This reflects that the choice of new media by the society depends on the media itself and is intrinsically linked to the whole social communication environment.Therefore,from the point of view of media evolution,the view that engraving originated in the early Tang Dynasty is not in line with the logic of media evolution and is unreasonable. 展开更多
关键词 media evolution origin of engraving and printing Early Tang theory questioning
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Mg-C-O isotopes and elements reveal the origin of dolostone in the Middle Jurassic Buqu Formation
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作者 Xi Li An-Jiang Shen Rui-Lin Hao 《Petroleum Science》 2025年第2期574-587,共14页
The origin of dolostone in the Middle Jurassic Buqu Formation of the Plateau Basin has been a subject of prolonged debate.This study combines detailed petrological observations with analyses of Mg-C-O isotopes and ele... The origin of dolostone in the Middle Jurassic Buqu Formation of the Plateau Basin has been a subject of prolonged debate.This study combines detailed petrological observations with analyses of Mg-C-O isotopes and elements to constrain the origin of dolostones in the Buqu Formation.Petrography and cathodoluminescence(CL)examination identified three types of matrix dolostones:very finely to finely crystalline dolostone(D1),finely to medium crystalline dolostone(D2),and medium to coarsely crystalline dolostone(D3).The analysis of the diagenesis sequence reveals that D1 originated from the dolomitization of grainstone in the early diagenetic phase,whereas D2 and D3 resulted from the recrystallization of D1 during the later burial phase.The presence of high Na(>100 ppm),low Fe(<1000 ppm),low Mn(<250 ppm),positive Ce anomaly,LREE enrichment,stableδ^(26)Mg(-2.28‰to-2.04‰),andδ^(13)C(1.02‰-2.95‰)indicates that the early dolomitization fluid was oxidized seawater.As the crystal size increases(D1→D2→D3),the progressively rising Mn content and significantly negativeδ^(18)O(-10.72‰to-7.81‰)suggest that the dolostone has experienced modification and alteration by buried pore water in the later stages.The fluctuations in relative sea level during the sedimentary deposition of the Buqu Formation were reconstructed through the utilization of Na,Sr/Cu,Sr/Ba,Rb/Sr,∑REE,andδ^(13)C.It was observed that theδ^(26)Mg of dolostone closely mirrored the variations in sea level.The consistent trend of change confirms that sea level fluctuations control the formation and distribution of early dolostone.Frequent sea level rise and fall prompted the limestone deposited on the carbonate platform to be continuously transformed into dolostone,which accumulates over a long period to form large-scale thick dolostone.After the formation entered the burial stage,under the combined action of high Mg/Ca ratio pore water,high temperature,and high pressure,the early dolostone experienced the adjustment of burial dolomitization.This research offers a typical case study on the application of Mg-C-O isotope and elements to determine the origin of dolostone.This will aid in a more comprehensive understanding of the formation process of dolostone in ancient rock records. 展开更多
关键词 origin of dolostone Mg-C-O isotopes Sea level changes Burial adjustment dolomitization Buqu formation Plateau basin
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Origin and distribution model of thin dolomite reservoirs in the lower sub-member of Mao 2 Member of Middle Permian Maokou Formation in Wusheng-Tongnan area,Sichuan Basin,SW China
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作者 TAN Xiucheng HE Ruyi +7 位作者 YANG Wenjie LUO Bing SHI Jiangbo ZHANG Lianjin LI Minglong TANG Yuxin XIAO Di QIAO Zhanfeng 《Petroleum Exploration and Development》 2025年第1期125-142,共18页
This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area o... This paper discusses the characteristics and formation mechanism of thin dolomite reservoirs in the lower submember of the second member of the Permian Maokou Formation(lower Mao 2 Member)in the Wusheng-Tongnan area of the Sichuan Basin,SW China,through comprehensive analysis of geological,geophysical and geochemical data.The reservoir rocks of the lower Mao 2 Member are dominated by porphyritic vuggy dolomite and calcareous dolomite or dolomitic limestone,which have typical karst characteristics of early diagenetic stage.The dolomites at the edge of the karst system and in the fillings have dissolved estuaries,and the dolomite breccia has micrite envelope and rim cement at the edge,indicating that dolomitization is earlier than the early diagenetic karstification.The shoal facies laminated dolomite is primarily formed by the seepage reflux dolomitization of moderate-salinity seawater.The key factors of reservoir formation are the bioclastic shoal deposition superimposed with seepgae reflux dolomitization and the karstification of early diagenetic stage,which are locally reformed by fractures and hydrothermal processes.The development of dolomite vuggy reservoir is closely related to the upward-shallowing sequence,and mainly occurs in the late highstand of the fourth-order cycle.Moreover,the size of dolomite is closely related to formation thickness,and it is concentrated in the formation thickness conversion area,followed by the thinner area.According to the understanding of insufficient accommodation space in the geomorphic highland and the migration of granular shoal to geomorphic lowland in the late highstand of the third-order cycle,it is proposed that the large-scale shoal-controlled dolomite reservoirs are distributed along structural highs and slopes,and the reservoir-forming model with shoal,dolomitization and karstification jointly controlled by the microgeomorphy and sea-level fluctuation in the sedimentary period is established.On this basis,the paleogeomorphology in the lower Mao 2 Member is restored using well-seismic data,and the reservoir distribution is predicted.The prediction results have been verified by the latest results of exploration wells and tests,which provide an important reference for the prediction of thin dolomite reservoirs under similar geological setting. 展开更多
关键词 reservoir origin sedimentary paleogeomorphology granular shoal thin reservoir DOLOMITE vuggy reservoir KARST Middle Permian Maokou Formation Sichuan Basin
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Disseminated mucormycosis originating from the stomach
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作者 Yongli Han Mengting Liu +1 位作者 Weiping Huang Hongke Zeng 《World Journal of Emergency Medicine》 2025年第5期508-510,共3页
Disseminated mucormycosis is a life-threatening fungal infection with high mortality,particularly in immunocompromised patients.Early diagnosis and prompt intervention are crutial but often delayed due to nonspecific ... Disseminated mucormycosis is a life-threatening fungal infection with high mortality,particularly in immunocompromised patients.Early diagnosis and prompt intervention are crutial but often delayed due to nonspecific presentations.Many studies have highlighted the challenges in emergency settings,where atypical symptoms may lead to misdiagnosis.We report a rare case of disseminated mucormycosis originating from the stomach in a pregnancy-induced thrombocytopenia(PITP)patient,emphasizing rapid gastroscopy examination,histopathological confi rmation,multidisciplinary management,and high-risk factors for hospital-acquired gastrointestinal mucormycosis infection. 展开更多
关键词 disseminated mucormycosis pregnancy induced thrombocytopenia rapid gastroscopy exam multidisciplinary management histopathological confirmation prompt intervention stomach origin rapid gastroscopy
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An iteration-free approach for determining the average reservoir pressure and original gas in place by production data analysis:Methodology and field cases
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作者 Yang Wang Shilong Yang +2 位作者 Hang Xie Naichao Feng Haiyang Yu 《Natural Gas Industry B》 2025年第3期328-338,共11页
Current gas well decline analysis under boundary-dominated flow(BDF)is largely based on the Arps'empirical hyperbolic decline model and the analytical type curve tools associated with pseudo-functions.Due to the n... Current gas well decline analysis under boundary-dominated flow(BDF)is largely based on the Arps'empirical hyperbolic decline model and the analytical type curve tools associated with pseudo-functions.Due to the nonlinear flow behavior of natural gas,these analysis methods generally require iterative calculations.In this study,the dimensionless gas rate(qg/qgi)is introduced,and an explicit method to determine the average reservoir pressure and the original gas in place(OGIP)for a volumetric gas reservoir is proposed.We show that the dimensionless gas rate in the BDF is only the function of the gas PVT parameters and reservoir pressure.Step-by-step analysis procedures are presented that enable explicit and straightforward estimation of average reservoir pressure and OGIP by straight-line analysis.Compared with current techniques,this methodology avoids the iterative calculation of pseudo-time and pseudo-pressure functions,lowers the multiplicity of type curve analysis,and is applicable in different production situations(constant/variable gas flow rate,constant/variable bottom-hole pressure)with a broad range of applications and ease of use.Reservoir numerical simulation and field examples are thoroughly discussed to highlight the capabilities of the proposed approach. 展开更多
关键词 Gas rate decline original gas in place Average reservoir pressure Explicit calculation Dynamic production analysis
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Investigation on the Historical Origins of Traditional Chinese Medicine Diagnosis and Treatment of“Ruyong(Breast Abscess)”
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作者 Qi Liu Ke Li +2 位作者 Yazhou Han Mingru Wang Xufeng Cheng 《Chinese Medicine and Natural Products》 2025年第2期86-93,共8页
“Ruyong(breast abscess)”has a high incidence rate.Traditional Chinese medicine(TCM)diagnosis and treatment of this condition demonstrate significant advantages,including diverse therapeuticmethods,outstanding effica... “Ruyong(breast abscess)”has a high incidence rate.Traditional Chinese medicine(TCM)diagnosis and treatment of this condition demonstrate significant advantages,including diverse therapeuticmethods,outstanding efficacy,and high safety.Based on TCM theory and combining relevant ancient texts and modern research,this paper systematically summarizes the different understandings of“Ruyong(breast abscess)”by physicians throughout history in terms of disease names,etiology,pathogenesis,and treatment.The ancient names for Ruyong(breast abscess)were varied,also referred to as“Duru(stagnation in breast)”or“Naichuang(breast sore)”.Its symptoms are diverse,with the main clinical manifestations being localized redness,swelling,heat,pain,and poor milk discharge in the affected breast.The etiology is primarily attributed to“milk stasis”“liver qi stagnation and stomach heat”and“exposure to external pathogens”.Additionally,this paper summarizes the treatment experiences from ancient and modern medical texts and highlights the complementary effects of internal and external therapies.This study provides a reference for modern clinical understanding and treatment of“Ruyong(breast abscess)”in the hope of further improvement of clinical efficacy. 展开更多
关键词 Ruyong breast abscess Duru(stagnation in breast) Naichuang(breast sore) historical origins disease name etiology and pathogenesis treatment methods
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Wave velocities and anisotropy of rocks:Implication for origin of low velocity zone of the Qinling Orogenic Belt,China
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作者 Lei Liu Ying Li +8 位作者 Tingting Li Hanyu Wang Shasha Liu Panpan Zhao Gerile Naren Li Yi Hong Liu Fengxia Sun Jianguo Du 《Geoscience Frontiers》 2025年第1期393-405,共13页
Structure and composition of Earth are fundamental importance in exploring the dynamic evolution of the crust and mantle.The Qinling Orogenic Belt(QOB)is located between the North China plate and the South China Plate... Structure and composition of Earth are fundamental importance in exploring the dynamic evolution of the crust and mantle.The Qinling Orogenic Belt(QOB)is located between the North China plate and the South China Plate,and is one of the main orogenic belts in China.To explore the composition and origin of anisotropy and the low wave velocity zone of the QOB,ten rock samples(gneiss and schist)were collected from the five sites of the QOB and the P-and S-wave velocities of these samples were measured under 0.6 to 2.0 GPa and 100 to 550℃.The wave velocities increase with increasing pressure and decreasing temperature.The V_(P)and V_(S)of the schist and gneiss match the velocity of the middle and lower crust of the QOB,indicating that schist and gneiss are important component of the QOB.All the schist and gneiss samples exhibit obvious seismic anisotropy with 1.64%-17.42%for V_(S)and 2.93%-14.78%for V_(P)under conditions of crust and upper mantle.The CPO/LPO and layering distribution of mica in rock samples are the main reasons for this anisotropy.The V_(S)structures below the five sampled sites from seismic ambient noise tomography were built to explore the effect of schist and gneiss on the composition and structure of the QOB.The results indicate that orientation-arranged gneiss and schist driven by the tectonic stresses might be a new origin of the character of V_(P)/V_(S),seismic anisotropy,and the low velocity zone in the QOB. 展开更多
关键词 Wave velocity of rock ANISOTROPY origin of low velocity zone The Qinling Orogenic Belt
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