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Enrichment characteristics of normal-pressure marine shale gas in the complex tectonic zone: a case study of the Lower Cambrian Niutitang Formation in northern Guizhou

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Journal of Earth Science 2024年

作者： Wenjibin Sun Zhonghu wu Yujun Zuo Chao Pan Hao Liu Baofeng Lan Jianyun Lin Bin Chen Qinggang Chen Guizhou Energy Industry Research Institute Co.， Ltd Mining College， Guizhou university College of Resource and Environmental Engineering， Guizhou university College of Civil Engineering， Guizhou university

The Lower Cambrian Niutitang Formation is a crucial stratum for the exploration of normal-pressure marine shale gas in southern china， with great development potential. To research the normal-pressure shale gas accumulation of the Niutitang Formation in the complex tectonic zone， the shale cores in northern Guizhou were subjected to X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) observation， and tests were conducted to determine total organic content (TOC)， bitumen reflectance， and nitrogen isotopes. The results indicate that the equivalent vitrinite reflectance of cores varies from 2.30% to 3.73%， and the TOC content of cores varies from 3.8% to 7.8%. The total gas content of three wells in northern Guizhou is 0.5 m3/t， 0.3 m3/t， and 1.4 m3/t， respectively. The TOC content of the shale in the syncline structure is higher than that of the shale in the anticline structure. Nitrogen in shale gas originates primarily from the thermal ammoniation of organic matter， the atmosphere， and the deep crust. Shale gas preservation is favourable in regions with a large range of lifting， and small lifting differences. The syncline is broad and gentle with few faults have better gas accumulation conditions. The Niutitang Formation in the residual syncline of the study area has better gas content than that of other structures. Exploration of shale gas accumulation sweet spots in northern Guizhou should focus on the broad-gentle synclines with minimal changes in stratigraphic lifting， few faults， and no hydrothermal activity at the edges of paleo-uplifts.

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Picroside Ⅱ promotes HSC apoptosis and inhibits the cholestatic liver fibrosis in Mdr2-/- mice by polarizing M1 macrophages and balancing immune responses

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Chinese Journal of Natural Medicines 2024年第07期 582-598页

作者： JIA Kexin MA Zhi ZHANG Yinhao XIE Kaihong LI Jianan wu Jianzhi QU Jiaorong LI Fanghong LI Xiaojiaoyang School of Life Sciences Beijing University of Chinese Medicine School of Chinese Materia Medica Beijing University of Chinese Medicine

Liver fibrosis is characterized by chronic inflammatory responses and progressive fibrous scar formation. Macrophages play a central role in the pathogenesis of hepatic fibrosis by reconstructing the immune microenvironment. Picroside Ⅱ（PIC Ⅱ）,extracted from Picrorhizae Rhizoma, has demonstrated therapeutic potential for various liver damage. However, the mechanisms by which macrophage polarization initiates immune cascades and contributes to the development of liver fibrosis, and whether this process can be influenced by PIC Ⅱ, remain unclear. In the current study, RNA sequencing and multiple molecular approaches were utilized to explore the underlying mechanisms of PIC Ⅱ against liver fibrosis in multidrug-resistance protein 2 knockout(Mdr2-/-) *** findings indicate that PIC Ⅱ activates M1-polarized macrophages to recruit natural killer cells（NK cells）, potentially via the CXCL16-CXCR6 axis. Additionally, PIC Ⅱ promotes the apoptosis of activated hepatic stellate cells（a HSCs） and enhances the cytotoxic effects of NK cells, while also reducing the formation of neutrophil extracellular traps（NETs）. Notably, the anti-hepatic fibrosis effects associated with PIC Ⅱ were largely reversed by macrophage depletion in Mdr2-/-mice. Collectively, our research suggests that PIC Ⅱ is a potential candidate for halting the progression of liver fibrosis.

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Wave Motion of Smoke in Subway Fire Environment

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Transactions of Tianjin university 2009年第3期15卷 206-209页

作者：吴文忠由世俊 School of Environmental Science and Engineering Tianjin University

Wave motion in subway or tunnel fire is an intrinsic property of *** the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equations of its mass and momentum,under nearly homogeneous zone *** smoke movement of 4 subway fires was simulated with *** fitting the pressure-mass functions to the simulated data,wave equations of the smoke were derived,and wave motions of smoke were thus *** can be seen that smoke wave is a kind of mass wave,whose velocity is inversely proportional to smoke mass,and wave of a bigger fire propagates slower.

关键词： subway fire environment smoke movement wave propagation

A Highly selective and Sensitive Fluorescent Probe Based Phenoxynaphthacenequinone Derivative for Cu2+

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A Highly selective and Sensitive Fluorescent Probe Based Phe...

基于AHP-FCE模型的桥梁设计风险评估研究

中国化学会第十届全国有机合成化学学术研讨会

作者： Wei Yan,Xin Zhou,Xue wu Department of chemistry,Yanbian university,Yanji,Jilin,P.R.china

Copper is the third mostabundant essential trace element in the human body and iscommonly found as Cu in natural *** the toxicityof Cu is low compared to other heavy metals but certain microorganisms are affected by even submicro-molarconcentrationsof ***,there exist a great intensting to construct fluorescent probe for ***,we desighed and synthesized a phenoxynaphthacenequinone-basedprobe(NQPy) for *** crystal stucture of NQPy is discribed under *** displayed highly sensitive and selective detection of Cu in aqueous ***

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来源： cnki会议评论

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土木工程学报 2010年第S2期43卷 275-280页

作者：项贻强吴强强张婷婷浙江大学绿色建筑和低碳城市建设研究中心浙江杭州310058

由于桥梁在设计过程中存在的风险未经过很好的识别与防范,导致由于工程设计原因造成的重大事故屡见不鲜。按照桥梁设计的基本生命周期进行设计风险划分,提出桥梁的设计风险评价指标,并且基于层次分析法(AHP)结合专家打分建立各指标的权... 详细信息

由于桥梁在设计过程中存在的风险未经过很好的识别与防范,导致由于工程设计原因造成的重大事故屡见不鲜。按照桥梁设计的基本生命周期进行设计风险划分,提出桥梁的设计风险评价指标,并且基于层次分析法(AHP)结合专家打分建立各指标的权重,再利用模糊综合评价法(FCE)建立模糊评价集,并利用zadeh算子对设计风险概率和设计风险损失进行计算,进而根据风险评估矩阵得到桥梁的设计风险水平。作为实例,运用AHP-FCE模型对灵江大桥的桥梁设计风险进行了分析评估。

关键词：桥梁工程设计风险层次分析法(AHP) 模糊综合评价法(FCE) Zadeh算子风险损失

三臂非劣效临床试验基于干预依从性的效应估计方法

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中国卫生统计 2024年第2期41卷 213-217,222页

作者：吴研鹏陈平雁吴莹复旦大学公共卫生学院流行病学教研室公共卫生安全教育部重点实验室 200032 南方医科大学公共卫生学院生物统计学系

目的临床试验中干预不依从问题通常无法避免,分析方法不当会导致结果偏倚,非劣效研究尤其如此。本研究针对三臂非劣效临床试验,建立Bayes因果模型,实现对干预依从人群的效应估计。方法基于主分层思想,按依从性类型将试验人群分层,从而... 详细信息

目的临床试验中干预不依从问题通常无法避免,分析方法不当会导致结果偏倚,非劣效研究尤其如此。本研究针对三臂非劣效临床试验,建立Bayes因果模型,实现对干预依从人群的效应估计。方法基于主分层思想,按依从性类型将试验人群分层,从而转化为不同依从性人群的结局混合分布识别问题。通过构建Bayes模型和使用DA(data augmentation)算法,实现结局参数后验分布估计和统计推断。通过模拟研究,比较本研究提出方法与传统的意向性治疗(intention-to-treat,ITT)、遵循研究方案(per-protocol,PP)及实际接受治疗(as-treated,AT)分析的统计性能。结果当依从类型与结局相关时,传统的ITT、PP及AT分析均存在较大偏倚;本研究提出方法在依从类型与结局相关和不相关两种情况下,均能够将偏倚控制在较小的范围。结论对于存在较严重干预不依从问题的非劣效临床试验,本研究提出方法较传统分析可以更好地控制分析偏倚。

关键词：不依从三臂非劣效性临床试验 Bayes因果模型 DA算法

The change of geographical distribution of two Asian species of rhinoceros in Holocene

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Journal of Geographical Sciences 1998年第1期8卷 84-89页

作者： Liu Hongjie Department of Geography, South china Normal university, Guangzhou 510631, china

At present only five species of rhinoceros surrive in the world, among which three in Asia No wild rhinoceros has been found alive in East Asia now But many recent evidences reveal the fact that rhinoceros still lived not very long ago in the East Asian Continent of Holocene The attention to East Asia rhinoceros in Holocene first arose from archaeological studies on ancient ruins in china Archaeologists first found some subfossil skeletons of rhinoceros in ruins of Yin Dynasty in Anyang of Henan in the 1930s Then more skeletons of rhinoceros were found in many other Neolithic Ages runis, such as in Tonghai (Yunnan), Nanning (Guangxi), Xichuan (Henan), Yuyao (zhejiang), and Haian (Jiangsu).(Guangxi Archaeological Team 1972; Jia 1977; wu 1983; Huang and Liang 1984; Xu 1990). Moreover, Zhou Benxiong reported some rhinoceros teeth containing residual organic matter found in caves in the middle and lower reaches of Yangtze River According to a number of very now skeletons of rhinoceros found in some caves in Central china and South china, Yang Zhongjian drew the inferences that rhinoceros might live in the Southern part of china until in the Han Dynasty (about 2000 yrs B P ) at least These discoveries provided the material evidences for the distribution of rhinoceros in East Asian Continent Recently, some scholars brought forward more new information about Chinese rhinoceros from the analysis of historical records and investigations of unearthed cultural relics respectively (Wen and He 1981; Sun 1982). Based on the above materials and informations, this paper is going to deal with the species of rhinoceros once living in East Asia from the viewpoint of zoo geography At last, we brouhgt up the evolution process of the rhinoceros in distribution in Asia with comprehensive analysis of physiographical elements and human activities

关键词： rhinoceros geographical distribution evolution process East Asia Holocence

Nitrogen Removal in Wastewater Irrigation Systems and Its Influence on Groundwater Pollution

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Journal of Earth Science 1995年第2期14卷 108-113页

作者： Wang Min wu Yongfeng Tang Minggao Zhong Zuoxin Shen ZhaoliHydrogeological Department , china university of Geosciences , Beijing 100083

The experiment included ten soil columns and field investigation in 1 - 2 year duration. Data on the columns continuously flooded with waste water indicated that when total input of NH4-N reached to above 70% of the NH4-N adsorption capacity in soil the breakthrough would appear in the output . Adequate removal of nitrogen from the waste water would require at least 170 cm deep groundwater table . Fine textured soil would promote denitrification . The columns simulating discontinuous waste water irrigation indicated that denitrification existed only in the partial microenvironment of reduction .Groundwater table depth had no strong influence on nitrogen removal . The investigation in field revealed that the groundwater recharged with waste water was not polluted by nitrogen when the aeration profile was in finer textures owing to the combined contribution of nitrification and denitrification .

关键词： wastewater irrigation system nitrogen removal groundwater pollution nitrification denitrification .

Ice-covered Environmental Adaptability Assessment for Overhead Contact System in High-speed Railways

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Chinese Journal of Electrical Engineering 2024年第2期10卷 70-79页

作者： Huan Zhang Wenfu Wei Like Pan Zefeng Yang Guizao Huang Yuxin Liu Xing Chen Ziqian Yang Guangning wu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China National Rail Transit Electrification and Automation Engineering Technology Research Center Southwest Jiaotong UniversityChengdu 611756China china Academy of Railway Sciences Corporation Limited Beijing 100000China

High-speed trains rely on pantograph-catenary systems(PCSs)to collect electrical energy from power ***,the dynamic interaction between the pantograph and the catenary system may become mismatched once ice accumulates on the overhead *** frequent arcing may occur within the PCS during train operation,posing an unpredictable threat to operational ***,it is crucial to evaluate the ability of overhead contact system(OCS)to withstand ice-covered variability during line desgin.A new strategy is proposed to evaluate the adaptive performance of an OCS under various icing ***,a dynamic model considering icing conditions is constructed to simulate the interaction within the *** different OCS structures with various icing thicknesses are *** parameters of the contact force within the PCS and proportion of high-possibility arcing moments are *** dependence of the contact force on the icing thickness and pantograph displacement has been illustrated in the form of cloud ***,the OCS sensitivity coefficient is calculated,and ice-covered environmental adaptability assessments for the five different OCS structures are compared.

关键词： Overhead contact system environmental adaptability sensitivity coefficient icing thickness contact force