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Hydrocarbon accumulation and key exploration & development technologies of Changning-Weiyuan marine shale gas field, southern Sichuan

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Petroleum Research 2021年第1期6卷 1-15页

作者： Xiao He Jianfa Wu Rui Yong Shengxian Zhao PetroChina Southwest Oil&Gas Field Company Chengdu610051China

China is rich in shale gas resources and has broad prospects for development. However, the quality ofshale gas resources in China is different from that in the United States, so independent unique technologies are urgently required in China. In this regard, PetroChina has carried out theoretical andtechnical researches systematically on shale gas in Longmaxi Formation in southern Sichuan according toits geology-engineering characteristics. Guided by the “three-control” theory for marine shale gasenrichment and high yield (i.e. sedimentary diagenesis controls reservoir, preservation conditions control accumulation, and continuous thickness of Type I reservoir controls production), six key explorationand development technologies in southern China have been innovatively developed for marine shale gaswhich experienced multi-stage tectonic evolution. The technologies include comprehensive geologicalevaluation technology, development optimization technology, optimal and fast drilling technology forhorizontal well, volume fracturing technology for horizontal well, factory-like operation technology, andefficient clean production technology. These technologies have enabled the large-scale commercial recovery of shale gas. By the end of 2019, PetroChina had obtained proved geological reserves of1.06 1012 m3, had built production capacity of 10 109 m3, and had cumulative gas production of20 109 m3 in southern Sichuan. The remarkable results of application are of great significance forvigorously developing shale gas industry to reduce external dependence, ensure national energy security,and realize the strategy of "ecological priority and green development".

关键词： Shale gas Exploration and development Hydrocarbon accumulation condition Horizontal well Optimization Fracturing Changning-weiyuan area Southern sichuan

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A New Dynamics Analysis Model for Five-Axis Machining of Curved Surface Based on Dimension Reduction and Mapping

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 172-184页

作者： Minglong Guo zhaocheng Wei Minjie Wang Zhiwei zhao shengxian Liu Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024People’s Republic of China Institute of Mechanical Manufacturing Technology China Academy of Engineering PhysicsMianyang 621000China

The equipment used in various fields contains an increasing number of parts with curved surfaces of increasing size.Five-axis computer numerical control(CNC)milling is the main parts machining method,while dynamics analysis has always been a research hotspot.The cutting conditions determined by the cutter axis,tool path,and workpiece geometry are complex and changeable,which has made dynamics research a major challenge.For this reason,this paper introduces the innovative idea of applying dimension reduction and mapping to the five-axis machining of curved surfaces,and proposes an efficient dynamics analysis model.To simplify the research object,the cutter position points along the tool path were discretized into inclined plane five-axis machining.The cutter dip angle and feed deflection angle were used to define the spatial position relationship in five-axis machining.These were then taken as the new base variables to construct an abstract two-dimensional space and establish the mapping relationship between the cutter position point and space point sets to further simplify the dimensions of the research object.Based on the in-cut cutting edge solved by the space limitation method,the dynamics of the inclined plane five-axis machining unit were studied,and the results were uniformly stored in the abstract space to produce a database.Finally,the prediction of the milling force and vibration state along the tool path became a data extraction process that significantly improved efficiency.Two experiments were also conducted which proved the accuracy and efficiency of the proposed dynamics analysis model.This study has great potential for the online synchronization of intelligent machining of large surfaces.

关键词： Curved surface Five-axis machining Dimension reduction and mapping Milling force Dynamics

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CO_(2),N_(2),and CO_(2)/N_(2)mixed gas injection for enhanced shale gas recovery and CO_(2)geological storage

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Frontiers in Energy 2023年第3期17卷 428-445页

作者： Jianfa WU Haoran HU Cheng CHANG Deliang ZHANG Jian ZHANG Shengxian Zhao Bo WANG Qiushi ZHANG Yiming CHEN Fanhua ZENG Shale Gas Research Institute Petro-China Southwest Oil and Gas-field CompanyChengdu 610051China Faculty of Engineering and Applied Science University of ReginaSK S4S 0A2Canada Department of Petroleum and Natural Gas Engineering Liaoning Petrochemical UniversityFushun 113001China

In this work,using fractured shale cores,isothermal adsorption experiments and core flooding tests were conducted to investigate the performance of injecting different gases to enhance shale gas recovery and CO_(2)geological storage efficiency under real reservoir conditions.The adsorption process of shale to different gases was in agreement with the extended-Langmuir model,and the adsorption capacity of CO_(2)was the largest,followed by CH_(4),and that of N_(2)was the smallest of the three pure gases.In addition,when the CO_(2)concentration in the mixed gas exceeded 50%,the adsorption capacity of the mixed gas was greater than that of CH4,and had a strong competitive adsorption effect.For the core flooding tests,pure gas injection showed that the breakthrough time of CO_(2)was longer than that of N_(2),and the CH_(4)recovery factor at the breakthrough time(Rch,)was also higher than that of N_(2).The RcH of CO_(2)gas injection was approximately 44.09%,while the RcH,of N_(2)was only 31.63%.For CO_(2)/N_(2)mixed gas injection,with the increase of CO_(2)concentration,the RcH,increased,and the RcH,for mixed gas CO_(2)/N_(2)=8:2 was close to that of pure CO_(2),about 40.24%.Moreover,the breakthrough time of N_(2)in mixed gas was not much different from that when pure N_(2)was injected,while the breakthrough time of CO_(2)was prolonged,which indicated that with the increase of N_(2)concentration in the mixed gas,the breakthrough time of CO_(2)could be extended.Furthermore,an abnormal surge of N_(2)concentration in the produced gas was observed after N_(2)breakthrough.In regards to CO_(2)storage efficiency(S_(Storage-CO_(2)),as the CO_(2)concentration increased,S storage-co_(2)also increased.The S storage-co_(2),of the pure CO_(2)gas injection was about 35.96%,while for mixed gas CO_(2)/N_(2)=8:2,S sorage-co,was about 32.28%.

关键词： shale gas gas injection competitive adsorption enhanced shale gas recovery CO_(2)geological storage

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Influence of Structural Parameters of Turbocharger Floating Bearing on Its Dynamic Characteristic Coefficients

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Journal of Beijing Institute of Technology 2017年第2期26卷 183-190页

作者： Junsheng zhao Yuantong Gu shengxian Yi Xuelong Lu School of Mechanical and Power Engineering North University of China School of Chemistry Physics and Mechanical EngineeringQueensland University of Technology

The structure parameters in an actual industrial production have a great influence on the coefficient of supercharger floating bearing dynamic characteristics,but there has been little systematic study so far.In this paper,the influence of structural parameters of the turbocharger floating bearing on its dynamic characteristic coefficientsis systematically investigated based on the theories of hydrodynamic lubrication and tribology.The influence of clearance ratio on eccentricity and the influence of internal to external radius ratios,and Sommerfeld number were analyzed.A new formula of responding characteristics of the oil film force caused by the displacement or velocity disturbance was deduced near an equilibrium in the steady state.Applying the newly developed formula,the dynamic characteristic was studied for floating bearings.Regularity for change of oil film stiffness and damping was analyzed with the structural parameters of floating bearing such as radius ratios and eccentricity.It has been found that the clearance ratio increases with eccentricity when the radius ratio is unchanged.The eccentricity decreases with the internal to external radius ratio of floating rings when the clearance ratio is constant.The absolute value of total principal stiffness and total main damping decrease with the clearance ratio and radius ratio of floating rings when the total cross damping is stable.The results and findings in this paper can contribute to nonlinear dynamics designs of turbocharger rotor-bearing systems.

关键词： turbocharger floating bearing structure parameters dynamic characteristic coefficient

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Research progress on isotopic fractionation in the process of shale gas/coalbed methane migration

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Petroleum Exploration and Development 2022年第5期49卷 1069-1084页

作者： LI Wenbiao LU Shuangfang LI Junqian WEI Yongbo zhao shengxian ZHANG Pengfei WANG Ziyi LI Xiao WANG Jun Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572025China Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development Ministry of EducationNortheast Petroleum UniversityDaqing 163318China School of Geosciences China University of Petroleum(East China)Qingdao 266580China Exploration and Development Research Institute of Daqing Oilfield Co.Ltd. Daqing 163712China Shale Gas Research Institute of PetroChina Southwest Oil&Gasfield Company Chengdu 610051China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

The research progress of isotopic fractionation in the process of shale gas/coalbed methane migration has been reviewed from three aspects: characteristics and influencing factors, mechanism and quantitative characterization model, and geological application. It is found that the isotopic fractionation during the complete production of shale gas/coalbed methane shows a four-stage characteristic of “stable-lighter-heavier-lighter again”, which is related to the complex gas migration modes in the pores of shale/coal. The gas migration mechanisms in shale/coal include seepage, diffusion, and adsorption/desorption. Among them, seepage driven by pressure difference does not induce isotopic fractionation, while diffusion and adsorption/desorption lead to significant isotope fractionation. The existing characterization models of isotopic fractionation include diffusion fractionation model, diffusion-adsorption/desorption coupled model, and multi-scale and multi-mechanism coupled model. Results of model calculations show that the isotopic fractionation during natural gas migration is mainly controlled by pore structure, adsorption capacity, and initial/boundary conditions of the reservoir rock. So far, the isotope fractionation model has been successfully used to evaluate critical parameters, such as gas-in-place content and ratio of adsorbed/free gas in shale/coal etc. Furthermore, it has shown promising application potential in production status identification and decline trend prediction of gas well. Future research should focus on:(1) the co-evolution of carbon and hydrogen isotopes of different components during natural gas migration,(2) the characterization of isotopic fractionation during the whole process of gas generation-expulsion-migration-accumulation-dispersion, and(3) quantitative characterization of isotopic fractionation during natural gas migration in complex pore-fracture systems and its application.

关键词： shale gas coalbed methane diffusive fractionation adsorption/desorption fractionation isotope fractionation model natural gas migration

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Prediction of decline in shale gas well production using stable carbon isotope technique

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Frontiers of Earth Science 2021年第4期15卷 849-859页

作者： Shengxian Zhao Shujuan KANG Majia ZHENG Shuangfang LU Yunfeng YANG Huanxu ZHANG Yongyang LIU Ziqiang XIA Chenglin ZHANG Haoran HU Di ZHU Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China School of Geosciences China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Shale Gas Institute of PetroChina Southwest Oil&Gasfield Company Chengdu 610000China Suzhou Grand Energy Technology Ltd. Suzhou 215129China

Prediction of shale gas production is a challenging task because of the complex fracture-pore networks and gas flow mechanisms in shale reservoirs.Empirical methods,which are used in the industry to forecast the future production of shale gas,have not been assessed sufficiently to warrant high confidence in their results.Methane carbon isotopic signals have been used for producing gas wells,and are controlled by physical properties and physics-controlling production;they serve as a unique indicator of the gas production status.Here,a workable process,which is combined with a gas isotope interpretation tool(also known as a numerical simulator),has been implemented in Longrnaxi shale gas wells to predict the production decline curves.The numerical simulator,which takes into account a convection-diffu-sion-adsorption model for the matrix and a convection model for fractures in^(13)CH_(4) and ^(12)CH_(4) isotopologues,was used to stabilize the carbon isotope variation in the produced gas to elucidate gas recovery.Combined with the production rates of the four developing wells,the total reserves ranged from 1.72×10^(8) to 2.02×10^(8) m^(3),which were used to constrain the trend of two-segment produc-tion decline curves that exhibited a transition from a hyperbolic equation to an exponential one within 0.82-0.89 year.Two-segment production decline curves were used to forecast future production and estimate ultimate recovery.

关键词： shale gas production decline Longmaxi formation carbon isotope

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Potential efficacy and mechanism of eight mild-natured and bitterflavored TCMs based on gut microbiota:A review

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Chinese Herbal Medicines 2024年第1期16卷 42-55页

作者： Wenquan Su Yanan Yang Xiaohui zhao Jiale Cheng Yuan Li shengxian Wu Chongming Wu Dongzhimen Hospital Beijing University of Chinese MedicineBeijing 100700China School of Chinese Materia Medica Tianjin University of Traditional Chinese MedicineTianjin 301617China Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine Tianjin 301617China

The mild-natured and bitter-flavored traditional Chinese medicines(MB-TCMs)are an important class of TCMs that have been widely used in clinical practice and recognized as safe long-term treatments for chronic diseases.However,as an important class of TCMs,the panorama of pharmacological effects and the mechanisms of MB-TCMs have not been systemically reviewed.Compelling studies have shown that gut microbiota can mediate the therapeutic activity of TCMs and help to elucidate the core principles of TCM medicinal theory.In this systematic review,we found that MB-TCMs commonly participated in the modulation of metabolic syndrome,intestinal inflammation,nervous system disease and cardiovascular system disease in association with promoting the growth of beneficial bacteria Bacteroides,Akkermansia,Lactobacillus,Bifidobacterium,Roseburia as well as inhibiting the proliferation of harmful bacteria Helicobacter,Enterococcus,Desulfovibrio and Escherichia-Shigella.These alterations,correspondingly,enhance the generation of protective metabolites,mainly including short-chain fatty acids(SCFAs),bile acid(BAs),5-hydroxytryptamine(5-HT),indole and gamma-aminobutyric acid(GABA),and inhibit the generation of harmful metabolites,such as proinflammatory factors trimethylamine oxide(TAMO)and lipopolysaccharide(LPS),to further exert multiplicative effects for the maintenance of human health through several different signaling pathways.Altogether,this present review has attempted to comprehensively summarize the relationship between MB-TCMs and gut microbiota by establishing the TCMs-gut microbiota-metabolite-signaling pathway-diseases axis,which may provide new insight into the study of TCM medicinal theories and their clinical applications.

关键词： bile acid gamma-aminobutyric acid 5-hydroxytryptamine mild-natured and bitter-flavored traditional Chinese medicines property theory short-chain fatty acids traditional Chinese medicine trimethylamine oxide

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Model identification of photovoltaic power generation efficiency with hot spot

Model identification of photovoltaic power generation effici...

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第32届中国控制与决策会议

作者： shengxian Cao Ying Su Bo zhao Xianshuang Yao School of Automation Engineering Northeast Electric Power University

In this paper,a hot spot model identification method is proposed for detecting the influence of hot spots on power generation efficiency.Based on the identification method,a guideline is given for the operation and maintenance of photovoltaic power stations.For the different strip hot spot areas,the experiment results show that that the strip hot spot area has an approximate exponential relationship with solar power generation efficiency.

关键词： Model identification Hot spot area Solar cells Power generation efficiency

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An Optimization Method Based on Adaptive Dynamic Programming for Cleaning Photovoltaic Panels

An Optimization Method Based on Adaptive Dynamic Programming...

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第三十九届中国控制会议

作者： Siyuan Fan Xianshuang Yao shengxian Cao Bo zhao School of Automation Engineering Northeast Electric Power University

Photovoltaic（PV） power generation has become one of the major energy in all the world. If the dust accumulation of PV power station is not cleaned in time, the production cost will be increased in power station. This paper seeks to develop a optimization model of cleaning to inform economic operation decision for PV power station. By setting the goal of the maximum output power and the minimum economic loss, a optimization method based on Adaptive Dynamic Programming（ADP） is proposed. A new cleaning strategy is proposed in this paper, and the simulation results show the effectiveness of this method. Taking a 12 WM PV power station in western Jilin Province in China as an example, the total maintenance cost of cleaning every 17 days is the lowest.

关键词： Adaptive Dynamic Programming optimization method PV panels cleaning strategy

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贸易政策不确定性对中国服务业全球价值链嵌入的影响研究

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天津商业大学学报 2024年第1期44卷 23-28页

作者：赵平姜胜贤贵州财经大学大数据应用与经济学院贵阳550025

利用亚洲开发银行投入产出数据,实证检验贸易政策不确定性对中国服务业全球价值链嵌入的影响,发现贸易政策不确定性上升会对服务业全球价值链嵌入产生正向冲击,并且贸易政策不确定性上升会通过刺激行业增加科研投入,提高其出口能力对行... 详细信息

利用亚洲开发银行投入产出数据,实证检验贸易政策不确定性对中国服务业全球价值链嵌入的影响,发现贸易政策不确定性上升会对服务业全球价值链嵌入产生正向冲击,并且贸易政策不确定性上升会通过刺激行业增加科研投入,提高其出口能力对行业全球价值链嵌入产生正向影响。异质性检验发现对外开放水平不同的行业受贸易政策不确定性的影响也有差异,内向型行业会受到贸易政策不确定性的负向冲击,而外向型行业则相反,行业贸易风险敞口会使贸易政策不确定性对价值链地位产生“U”形门槛效应。

关键词：贸易政策不确定性全球价值链服务贸易科技创新

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