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Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang bao-Zhi Pan Yu-Hang Guo Qing-Hui Wang Yao guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.However,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably difficult.At the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous formations.To overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous rocks.Specifically,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric model.Then we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and porosity.However,it is always difficult to determine the elemental eigenvalues of different minerals in inversion.This paper uses multiple linear regression methods to solve this problem.Finally,an integrated inversion technique for altered igneous formations was developed.The results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray diffraction.The results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formations.

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

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Data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang guan Dong-hong Wang Da Shu Shou-qin Zhu Xiao-yuan Ji bao-de Sun Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo simulation.The collected data includes four types of defects and corresponding process parameters were used to construct the RF model.Classification results show a recall rate above 90% for all categories.The Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF model.Finally,the classification model was applied to different production conditions for quality prediction.In the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature distribution.The prediction model,when applied to the factory,greatly improved the efficiency of defect detection.Results show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

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Numerical investigation on thermomechanical behavior of alumina–calcium hexaluminate refractories for purging plug

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Journal of Iron and Steel Research(International) 2024年第2期31卷 389-400页

作者： Li-ping Pan Ya-wei Li Fang-guan Tan Yi-chen Chen Yang-fan Xu Zhu He bao-kuan Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology Wuhan University of Science and TechnologyWuhan430081HubeiChina

Alumina–spinel refractories used in slit-type purging plugs are susceptible to cross-sectional damage,resulting in a serious mismatch between their service life and that of ladle.Alumina–calcium hexaluminate refractories have gradually become the new trend in purging plug materials with the development of refining technology.The thermomechanical damage of slit-type purging plugs with alumina–calcium hexaluminate refractory was investigated by the thermo-solid coupling simulation.Combined with the polynomial fitting and design of experiments methods,the influence of thermophysical parameters on temperature and thermal stress of alumina–calcium hexaluminate refractories for purging plugs was systematically analyzed.The results show that the maximum thermal stress of the purging plugs appears during the stages of steel transporting and stirring,and the vulnerable parts are located above Y=0.323 m.The thermal conductivity and the coefficient of thermal expansion of the material are the most sensitive parameters to the temperature and thermal stress inside the structure,respectively.The addition of more calcium hexaluminate can relieve the stress concentration and large deformation around the slits.Consequently,when the content of calcium hexaluminate is 47 wt.%and in the form of aggregate-binder,the temperature and thermal stress distribution inside the refractory are optimal,which can effectively improve the service life of the slit-type purging plug.

关键词： Purging plug Thermomechanical damage Refractory Design of experiments method Stress

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Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI bao-ping FAN Hong-yan WANG guan-nan RAO Xi GE Weifeng SHAO Xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health management.However,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating value.The complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL prediction.An RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is proposed.The performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data problems.Based on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance factors.An example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

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Engineering of oxygen vacancy and bismuth cluster assisted ultrathin Bi_(12)O_(17)Cl_(2)nanosheets with efficient and selective photoreduction of CO_(2)to CO

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Carbon Energy 2024年第4期6卷 1-11页

作者： Meili guan Ni Lu Xuan Zhang Qiuwan Wang Jian bao Guiye Chen Hao Yu Huaming Li Jiexiang Xia Xuezhong Gong College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdaoShandongChina Institute for Energy Research Jiangsu UniversityZhenjiangJiangsuChina National Center of International Joint Research for Hybrid Materials Technology Institute of Hybrid MaterialsCollege of Materials Science andEngineeringNational Base of International Science and Technology Cooperation on Hybrid MaterialsQingdao UniversityQingdaoShandongChina

The photocatalytic conversion of CO_(2)into solar‐powered fuels is viewed as a forward‐looking strategy to address energy scarcity and global warming.This work demonstrated the selective photoreduction of CO_(2)to CO using ultrathin Bi_(12)O_(17)Cl_(2)nanosheets decorated with hydrothermally synthesized bismuth clusters and oxygen vacancies(OVs).The characterizations revealed that the coexistences of OVs and Bi clusters generated in situ contributed to the high efficiency of CO_(2)–CO conversion(64.3μmol g^(−1)h^(−1))and perfect selectivity.The OVs on the facet(001)of the ultrathin Bi_(12)O_(17)Cl_(2)nanosheets serve as sites for CO_(2)adsorption and activation sites,capturing photoexcited electrons and prolonging light absorption due to defect states.In addition,the Bi‐cluster generated in situ offers the ability to trap holes and the surface plasmonic resonance effect.This study offers great potential for the construction of semiconductor hybrids as multiphotocatalysts,capable of being used for the elimination and conversion of CO_(2)in terms of energy and environment.

关键词： Bi cluster Bi_(12)O_(17)Cl_(2)nanosheet oxygen vacancy photocatalytic CO_(2)reduction

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论新时代以来行政法精神的变迁(2012-2022年)

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行政法学研究 2024年第1期 3-16页

作者：关保英上海政法学院法律学院上海201701

我国行政法经历了改革开放以来三十余年的发展和新时代以来十余年的发展。前三十余年,形成了作为一个独立法律部门并成为公法核心部类存在、兼顾权力与权利平衡以及追求程序正义的现代行政法治精神。新时代以来在习近平法治思想的指引下... 详细信息

我国行政法经历了改革开放以来三十余年的发展和新时代以来十余年的发展。前三十余年,形成了作为一个独立法律部门并成为公法核心部类存在、兼顾权力与权利平衡以及追求程序正义的现代行政法治精神。新时代以来在习近平法治思想的指引下,尤其随着社会主要矛盾的变化、法治国家现代化的到来、政治运作机制的转型、法治体系概念的提出,行政法精神的理论基础和社会基础都发生了变迁,为此新时代行政法侧重于以凸显行政法治体系化、行政法治问题应对、私方当事人介入、行政法典化诉求为时代特征。党的二十大召开后意味着行政法应当有更新的格局,既要保持新时代以来行政法精神的稳定性和主客观状态,同时也要契合时代气息,以体现厚实方法论支撑、契合全过程人民民主、趋于给付精神的引领、实体与程序的平衡、问题应对的精准性为主要趋向。

关键词：行政法精神变迁新时代以来行政法新趋势

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私域流量2.0时代出版企业的流量运营问题及策略

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出版发行研究 2024年第1期 24-30页

作者：鲍娴管慧勇杭州电子科技大学浙江人民美术出版社

私域流量是行业在流量运营实践中相对公域流量的粗略划分,经历了私域流量池初步构建的1.0时代,正进入如何运营以实现规模化、持续化收益的2.0时代。本文以带有数字经济基因的私域流量已成为出版行业努力探索的新风口为基点,对出版企业... 详细信息

私域流量是行业在流量运营实践中相对公域流量的粗略划分,经历了私域流量池初步构建的1.0时代,正进入如何运营以实现规模化、持续化收益的2.0时代。本文以带有数字经济基因的私域流量已成为出版行业努力探索的新风口为基点,对出版企业流量运营中面临的固流与沉淀、运营成本以及商业闭环三大问题进行分析,提出以产品和服务深耕固流以及以分层和差异化运营沉淀、以产品附加值的衍生和多元化形态的拓展降低私域流量的运营成本、以价值共创提升出版类品牌的建设力和以口碑传播实现私域流量运营闭环等策略,以期为当下出版领域中私域流量的运营提供思路。

关键词：私域流量出版流量运营

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“新工科”背景下复合材料与工程专业生产实践教学探索与思考

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高分子通报 2024年第3期37卷 400-404页

作者：管清宝孙巍游正伟东华大学材料科学与工程学院上海201620

“新工科”建设是国家对高等教育的一项重大战略部署,是新形势下人才培养模式的一次新探索,对促进我国高等教育改革和发展具有重要意义。着眼于培养符合国家战略和新产业发展需求的复合材料与工程专业高水平复合型人才,本教学团队于201... 详细信息

“新工科”建设是国家对高等教育的一项重大战略部署,是新形势下人才培养模式的一次新探索,对促进我国高等教育改革和发展具有重要意义。着眼于培养符合国家战略和新产业发展需求的复合材料与工程专业高水平复合型人才,本教学团队于2016年开始筹建“生产实践”课程,作为本专业主要实践课,从“复合材料+X”产教融合交叉人才培养模式、多方协同的实践和创新能力培养平台等多方位入手,并从教学手段、教学方法、教学内容等方面对该课程进行深度优化。本专业于2019年入选复合材料与工程专业全国第一个国家级一流本科专业建设点;2021年顺利通过专业教育工程认证;学生工程实践和创新能力显著提升,2017~2022年连续6年就业率达100%,深造率连年攀升,2022年达到82%。“生产实践”课程在从无到有、从有到精的建设和教学过程中所做的探索与实践为相关新工科专业人才培养体系的构建提供了有益的参考。

关键词：生产实践复合材料课程设计教学方法

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Dietary supplementation of benzoic acid and essential oils combination enhances intestinal resilience against LPS stimulation in weaned piglets

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Journal of Animal Science and Biotechnology 2024年第2期15卷 878-897页

作者： Chang Cui Yulong Wei Yibo Wang Wen Ma Xiaoyu Zheng Jun Wang Ziwei Ma Caichi Wu Licui Chu Shihai Zhang Wutai guan Fang Chen guangdong Provincial Key Laboratory of Animal Nutrition Control College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642China College of Animal Science and National Engineering Research Center for Breeding Swine Industry South China Agricultural UniversityGuangzhou 510642China guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhou 510642China

Background The benefits of combining benzoic acid and essential oils(bao)to mitigate intestinal impairment during the weaning process have been well established,while the detailed underlying mechanism has not been fully elucidated.Previous research has primarily focused on the reparative effects of bao on intestinal injury,while neglecting its potential in enhancing intestinal stress resistance.Methods In this study,we investigated the pre-protective effect of bao against LPS-induced stress using a modified experimental procedure.Piglets were pre-supplemented with bao for 14 d,followed by a challenge with LPS or saline to collect blood and intestinal samples.Results Our findings demonstrated that bao supplementation led to significant improvements in piglets’final weight,average daily gain,and feed intake/body gain ratio.Additionally,bao supplementation positively influenced the composition of intestinal microbiota,increasing beneficial Actinobacteriota and Alloprevotella while reducing harmful Desulfobacterota,Prevotella and Oscillospira.Furthermore,bao supplementation effectively mitigated oxidative disturbances and inflammatory responses induced by acute LPS challenge.This was evidenced by elevated levels of T-AOC,SOD,and GSH,as well as decreased levels of MDA,TNF-α,and IL-6 in the plasma.Moreover,piglets subjected to LPS challenge and pre-supplemented with bao exhibited significant improvements in intestinal morphological structure and enhanced integrity,as indicated by restored expression levels of Occludin and Claudin-1 compared to the non-supplemented counterparts.Further analysis revealed that bao supplementation enhanced the jejunal antioxidative capacity by increasing GSH-Px levels and decreasing MDA levels under the LPS challenge and stimulated the activation of the Nrf2 signaling pathway.Additionally,the reduction of TLR4/NF-κB/MAPK signaling pathways activation and proinflammatory factor were also observed in the jejunal of those piglets fed with bao.Conclusions In summary,our study demonstrates that

关键词： Anti-stress Benzoic acid Essential oils Intestine LPS Weaned piglets

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北京市综合医院老年糖尿病衰弱现状及其干预的动态评估

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中华中医药杂志 2024年第6期39卷 3138-3143页

作者：王宝张亚强关欣李怡北京医院中医科国家老年医学中心中国医学科学院老年医学研究院北京100730 首都医科大学附属北京同仁医院北京100730 北京医院党委办公室国家老年医学中心中国医学科学院老年医学研究院北京100730

目的:调查北京市综合医院中医科就诊的老年糖尿病患者衰弱现状及干预效果。方法:采用便利抽样法,选取2021年1—12月北京市7家综合医院中医科就诊的老年糖尿病患者为研究对象,根据实际是否采用系统中医药干预分为西医组和中西医结合组,... 详细信息

目的:调查北京市综合医院中医科就诊的老年糖尿病患者衰弱现状及干预效果。方法:采用便利抽样法,选取2021年1—12月北京市7家综合医院中医科就诊的老年糖尿病患者为研究对象,根据实际是否采用系统中医药干预分为西医组和中西医结合组,对其衰弱指数进行动态评估。结果:纳入西医组106例、中西医结合组154例,260例患者中衰弱期有170例,衰弱前期64例,无衰弱者26例,衰弱发生率65.38%;该人群证候以气虚、阴虚、血瘀证为主,气虚证、血虚证、阳虚证、湿证在衰弱期的老年糖尿病患者中的比例大于衰弱前期的患者(P<0.05);衰弱指数在气虚证、血虚证、阳虚证、痰浊证、湿证下比较,差异有统计学意义(P<0.01);相对西医组,中西医结合组可显著降低老年糖尿病患者的衰弱指数。结论:北京地区老年糖尿病患者的衰弱发生率高,中西医结合干预可有效改善其衰弱状况。

关键词：老年糖尿病衰弱指数衰弱状况中西医结合综合医院

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