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Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory

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Petroleum Science 2024年第2期21卷 1354-1368页

作者： Hui Wang Yang Yang Bin Xi Wei-Dong Shi Chuan Wang lei-lei ji Xiang-Yu Song Zhao-Ming He College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009JiangsuChina College of Electrical and Mechanical Engineering Nanchang Institute of TechnologyNanchang330044JiangxiChina College of Mechanical Engineering Nantong UniversityNantong226019JiangsuChina National Research Center of Pumps Jiangsu UniversityZhenjiang212013JiangsuChina Zhejiang Zhenxing Petrochemical Machinery Co. Ltd.Ruian325204ZhejiangChina Department of Mechanical Engineering of Texas Tech University Lubbock79411TXUSA

The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction *** lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristics and internal flow across stages are also introduced. In this study, the inter-stage variability of energy characteristics in ESP hydraulic systems is investigated through entropy production(EP) analysis,which incorporates numerical simulations and experimental validation. The EP theory facilitates the quantification of energy loss in each computational subdomain at all ESP stages, establishing a correlation between microscopic flow structure and energy dissipation within the system. Furthermore, the underlying causes of inter-stage variability in ESP hydraulic systems are examined, and the advantages and disadvantages of applying the EP theory in this context are evaluated. Consistent energy characteristics within the ESP, aligned with the distribution of internal flow structure, are provided by the EP theory, as demonstrated by our results. The EP theory also enables the quantitative analysis of internal flow losses and complements existing performance analysis methods to map the internal flow structure to hydraulic losses. Nonetheless, an inconsistency between the energy characterization based on EP theory and the traditional efficiency index when reflecting inter-stage differences is identified. This inconsistency arises from the exclusive focus of the EP theory on flow losses within the flow field, disregarding the quantification of external energy input to the flow field. This study provides a reference for the optimization of EP theory in rotating machinery while deeply investigating the energy dissipation characteristics of multistage hydraulic system, which has certain theoretical and practical significance.

关键词： Electric submersible pump(ESP) Entropy production theory Energy characteristics Inter-stage differences

Efficacy of physiological seawater nasal irrigation for the treatment of children with SARS-CoV-2 Omicron BA.2 variant infection:a randomized controlled trial

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World Journal of Pediatrics 2024年第5期20卷 461-469页

作者： ji-lei Lin Fen Zhang Yan-Bo Li Shu-Hua Yuan jin-Hong Wu jing Zhang lei Zhang Yi He jie Chen Yong Yin Department of Respiratory Medicine Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina University of British Columbia VancouverCanada Information Technology Department Shanghai Children’s Medical Center National Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Otorhinolaryngology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dongfang RoadPudong DistrictShanghaiChina Department of Respiratory Medicine Sanya Women and Children’s Hospital Affiliated to Hainan Medical CollegeHainan Branch of Shanghai Children’s Medical CenterSanyaChina Department of Respiratory Medicine Linyi Maternal and Child Healthcare HospitalLinyiChina Shanghai Children’s Medical Center Pediatric Medical Complex(Pudong) ShanghaiChina Pediatric AI Clinical Application and Research Center Shanghai Children’s Medical CenterShanghaiChina

Background Saline nasal irrigation is an effective therapy for relieving common cold *** study aimed to investigate and explore the efficacy of physiological seawater nasal irrigation(PSNI)on children with mild and asymptomatic infection with *** This randomized controlled trial was conducted in Shanghai,China,and 403 children with mild and asymptomatic infection with Omicron were *** children were allocated into the PSNI group and the control *** primary outcome was the duration of viral shedding(DVS),and the secondary outcome was the change in clinical *** The median age of all participants was 5.59(6.26)years *** DVS was significantly shorter in the PSNI group[2.40(1.13)]than in the control group[3.09(2.14)](P=0.014).The multivariable Cox regression model also showed that patients in the PSNI group had an increased probability of shorter DVS compared with patients in the control group[hazard ratio(HR),1.27;95%confidence interval(CI),1.04–1.55;P=0.017].Subgroup analysis suggested that the DVS of patients without full vaccination was significantly reduced in the PSNI *** proportions of runny nose and stuffy nose were apparently reduced in the first three days in the PSNI group or the control group,but there was no evidence showing that PSNI contributes to the benefit compared with the control *** PSNI can reduce the DVS of patients with mild and asymptomatic infection with SARS-CoV-2 Omicron BA.2 variant.

关键词： Children Duration of viral shedding Omicron Physiological seawater nasal irrigation

A sustainable process to 100%bio-based nylons integrated chemical and biological conversion of lignocellulose

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Green Energy & Environment 2024年第2期9卷 390-402页

作者： Ruijia Hu Ming Li Tao Shen Xin Wang Zhuohua Sun Xinning Bao Kequan Chen Kai Guo lei ji Hanjie Ying Pingkai Ouyang Chenjie Zhu College of Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjingChina National Engineering Research Center for Biotechnology Nanjing Tech UniversityNanjingChina Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijingChina

Considerable progress has been made in recent years to the development of sustainable polymers from bio-based *** this study,100%bio-based nylons were prepared via an integrated chemical and biological process from *** novel nylons were obtained by the melt polymerization of 3-propyladipic acid derived from lignin and 1,5-pentenediamine/1,4-butanediamine derived from carbohydrate *** to the concept is a three-step noble metal free catalytic chemical funnelling sequence(Raney Ni mediated reductive catalytic fractionation-reductive funnelling-oxidative funnelling),which allowed for obtaining a single component 3-propyladipic acid from lignin with high *** structural and thermodynamic properties of the obtained nylons have been systematically investigated,and thus obtained transparent bio-based nylons exhibited higher Mw(>32,000)and excellent thermal stability(Td5%>265℃).Considering their moderate Tg and good melt strength,these transparent bio-based nylons could serve as promising functional additives or temperature-responsive materials.

关键词： Lignocellulose Lignin Reductive catalytic fractionation Bio-based nylon

Simulation of deuterium pellet ablation and deposition in the EAST tokamak with HPI2 code

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Chinese Physics B 2024年第4期33卷 561-569页

作者：李大正张洁侯吉磊李懋孙继忠 Key Laboratory of Materials Modification by Laser Ionand Electron BeamsSchool of PhysicsDalian University of TechnologyDalian 116024China Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China

Pellet injection is a primary method for fueling the plasma in magnetic confinement *** that goal the knowledges of pellet ablation and deposition profiles are *** the present study,the pellet fueling code HPI2 was used to predict the ablation and deposition profiles of deuterium pellets injected into a typical H-mode discharge on the EAST *** ablation and deposition profiles were evaluated for various pellet injection locations,with the aim at optimizing the pellet injection to obtain a deep fueling *** this study,we investigate the effect of the injection angle on the deposition depth of the pellet at different velocities and *** ablation and deposition of the injected pellet are mainly studied at each injection position for three different injection angles:0°,45°,and 60°.The pellet injection on the high field side(HFS)can achieve a more ideal deposition depth than on the low field side(LFS).Among these angles,horizontal injection on the middle plane is relatively better on either the HFS or the *** the injection location is 0.468 m below the middle plane on the HFS or 0.40 m above the middle plane of the LFS,it can achieve a similar deposition depth to the one of its corresponding *** the pre-cooling effect is taken into account,the deposition depth is predicted to increase only slightly when the pellet is launched from the *** findings of this study will serve as a reference for the update of pellet injection systems for the EAST tokamak.

关键词： pellet injection pellet ablation HPI2 pellet deposition

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因果关系的反事实理论与超定问题

自然辩证法研究 2024年第2期40卷 50-57页

作者：吉磊南京大学哲学系南京210023

超定问题是对因果关系的反事实理论的一项根本挑战。面对超定问题,学界存在两种针锋相对的态度:一是直接否认超定存在的物理可能性,并将其案例化归为无害的联因致果;另一种则主张超定是物理可能的,并认为典型的超定案例普遍存在。这一... 详细信息

超定问题是对因果关系的反事实理论的一项根本挑战。面对超定问题,学界存在两种针锋相对的态度:一是直接否认超定存在的物理可能性,并将其案例化归为无害的联因致果;另一种则主张超定是物理可能的,并认为典型的超定案例普遍存在。这一争论促使人们重新思考超定的本质和定义方式,同时揭示出事件作为因果关系项或许具有隐秘的非同质性。经过澄清,所谓的典型超定案例并非真实的超定,真实的超定以结果迟钝性为标志,这一结论要求我们重新思考反事实理论的基底观念。

关键词：因果关系反事实理论超定物理可能迟钝性

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一类超线性双调和方程正解的存在性

安徽大学学报（自然科学版） 2024年第5期48卷 12-17页

作者：吉蕾晋中学院数学系山西晋中030619

研究以下双调和方程{Δ^(2)u+cΔu=f(x,u),x∈Ω,Δu=u=0,x∈∂Ω,其中Ω∈R^(N)是有界开集,其边界∂Ω光滑.c∈R,f:Ω×R→R是Caratheodory函数.当非线性项f(x,u)在无穷远处为超线性时,通过山路引理和强极大值原理获得了该方程的正解,所... 详细信息

研究以下双调和方程{Δ^(2)u+cΔu=f(x,u),x∈Ω,Δu=u=0,x∈∂Ω,其中Ω∈R^(N)是有界开集,其边界∂Ω光滑.c∈R,f:Ω×R→R是Caratheodory函数.当非线性项f(x,u)在无穷远处为超线性时,通过山路引理和强极大值原理获得了该方程的正解,所设条件弱于相关文献中的条件,使得非线性项更具一般性,从而推广了相关文献中关于超线性的结果.

关键词：双调和超线性变分方法正解

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Characterization of rock thermophysical properties and factors affecting thermal conductivity−A case study of Datong Basin,China

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Journal of Groundwater Science and Engineering 2024年第1期12卷 4-15页

作者： Meng-lei ji Shuai-chao Wei Wei Zhang Feng Liu Yu-zhong Liao Ruo-xi Yuan Xiao-xue Yan Long Li Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Technology Innovation Center of Geothermal&Hot Dry Rock Exploration and Development Ministry of Natural ResourcesShijiazhuang 050061China China University of Geosciences(Beijing) Beijing 100083China

Rock thermal physical properties play a crucial role in understanding deep thermal conditions,modeling the thermal structure of the lithosphere,and discovering the evolutionary history of sedimentary *** advancements in geothermal exploration,particularly the identification of high-temperature geothermal resources in Datong Basin,Shanxi,China,have opened new *** study aims to characterize the thermal properties of rocks and explore factors influencing thermal conductivity in basins hosting high-temperature geothermal resources.A total of 70 groups of rock samples were collected from outcrops in and around Datong Basin,Shanxi *** property tests were carried out to analyze the rock properties,and the influencing factors of thermal conductivity were studied through experiments at different temperature and water-filled *** results indicate that the thermal conductivity of rocks in Datong,Shanxi Province,typically ranges from 0.690 W/(m·K)to 6.460 W/(m·K),the thermal diffusion coefficient ranges from 0.441 mm^(2)/s to 2.023 mm^(2)/s,and the specific heat capacity of the rocks ranges from 0.569 KJ/(kg·℃)to 1.117 KJ/(kg·°C).Experimental results reveal the impact of temperature and water saturation on the thermal conductivity of the *** thermal conductivity decreases with increasing temperature and rises with high water saturation.A temperature correction formula for the thermal conductivity of different lithologies in the area is proposed through linear *** findings from this study provide essential parameters for the assessment and prediction,development,and utilization of geothermal resources in the region and other basins with typical high-temperature geothermal resource.

关键词： Datong Basin Rock thermal conductivity Thermal diffusivity Specific heat capacity Influencing factors

不对称催化合成手性1,2-双硼酸酯研究进展

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有机化学 2024年第5期44卷 1385-1402页

作者：吉崇磊高得伟上海科技大学物质科学与技术学院上海201210

手性1,2-双硼酸酯是合成化学中重要的转化砌块,其催化不对称合成引起了化学界的广泛关注.近年来,过渡金属和手性双醇催化的烯烃不对称双硼化反应已成为合成手性1,2-双硼酸酯的重要方法,基于烯基双硼化合物的不对称氢化反应,可以作为烯... 详细信息

手性1,2-双硼酸酯是合成化学中重要的转化砌块,其催化不对称合成引起了化学界的广泛关注.近年来,过渡金属和手性双醇催化的烯烃不对称双硼化反应已成为合成手性1,2-双硼酸酯的重要方法,基于烯基双硼化合物的不对称氢化反应,可以作为烯烃双硼化反应的补充来合成对应的目标产物.同时,烯烃或炔烃的硼化/官能团化也是构建这类化合物的另一种有效方法.最近,以偕二硼酸酯为起始物的催化不对称迁移增碳反应,为手性1,2-双硼酸酯的合成提供了新的思路.总结了手性1,2-双硼酸酯合成的最新研究进展及面临的挑战,并对未来的研究方向进行了展望.

关键词：手性1,2-双硼酸酯双硼化氢硼化硼化/官能团化偕二硼酸酯迁移偶联

新质生产力的科学内涵、构成要素和制度保障机制

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学习与探索 2024年第1期 92-101,175页

作者：赵峰季雷中国人民大学经济学院中国人民大学全国中国特色社会主义政治经济学研究中心北京理工大学马克思主义学院

科学把握新质生产力的内涵需要回到其形成和发展的社会历史背景中。本文遵循历史唯物主义的分析逻辑,从技术形态、发展阶段和人类社会生产力演进三个层面,探寻新质生产力的丰富内涵;通过对劳动过程的剖析解构新质生产力的构成要素,并分... 详细信息

科学把握新质生产力的内涵需要回到其形成和发展的社会历史背景中。本文遵循历史唯物主义的分析逻辑,从技术形态、发展阶段和人类社会生产力演进三个层面,探寻新质生产力的丰富内涵;通过对劳动过程的剖析解构新质生产力的构成要素,并分析其对社会再生产过程的影响;最后考察经济制度对新质生产力形成的重要作用。我们认为,新质生产力是新一轮产业技术革命及其战略性新兴产业集群形成的生产力,是新时代实现高质量发展必需的一类生产力,要融合提升传统生产力,展现新时代新活力。新质生产力的形成将对新时代社会生产组织方式和社会再生产过程产生重要影响。为形成新质生产力培育动力不仅要坚持创新驱动发展,还要依靠全面深化改革激发内生活力。中国共产党的领导是我国形成新质生产力的独有优势和根本保障。

关键词：新质生产力技术革命高质量发展劳动过程

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