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Investigations on High-Speed Flash Boiling Atomization of Fuel Based on Numerical Simulations

Computer Modeling in Engineering & Sciences 2024年第5期139卷 1427-1453页

作者： Wei Zhong Zhenfang Xin lihua wang Haiping Liu School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China Beijing Mechanical Equipment Research Institute Beijing100854China

Flash boiling atomization(FBA)is a promising approach for enhancing spray atomization,which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure.However,when the outlet speed of the nozzle exceeds 400 m/s,investigating high-speed flash boiling atomization(HFBA)becomes quite challenging.This difficulty arises fromthe involvement ofmany complex physical processes and the requirement for a very fine mesh in numerical simulations.In this study,an HFBA model for gasoline direct injection(GDI)is established.This model incorporates primary and secondary atomization,as well as vaporization and boilingmodels,to describe the development process of the flash boiling spray.Compared to lowspeed FBA,these physical processes significantly impact HFBA.In this model,the Eulerian description is utilized for modeling the gas,and the Lagrangian description is applied to model the droplets,which effectively captures the movement of the droplets and avoids excessive mesh in the Eulerian coordinates.Under various conditions,numerical solutions of the Sauter mean diameter(SMD)for GDI show good agreement with experimental data,validating the proposed model’s performance.Simulations based on this HFBA model investigate the influences of fuel injection temperature and ambient pressure on the atomization process.Numerical analyses of the velocity field,temperature field,vapor mass fraction distribution,particle size distribution,and spray penetration length under different superheat degrees reveal that high injection temperature or low ambient pressure significantly affects the formation of small and dispersed droplet distribution.This effect is conducive to the refinement of spray particles and enhances atomization.

关键词： High-speed flash boiling atomization numerical simulations Eulerian description Lagrangian description gasoline direct injection

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Stochastic speed prediction for connected vehicles using improved bayesian networks with back propagation

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Science China(Technological Sciences) 2022年第7期65卷 1524-1536页

作者： wang lihua CUI YaHui ZHANG FengQi COSKUN Serdar LIU KaiLong LI GuangLei School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China Department of Mechanical Engineering Tarsus UniversityTarsusMersin 33400Turkey WMG University of WarwickCoventryCV47ALUK

Advanced vehicular control technologies rely on accurate speed prediction to make ecological and safe decisions. This paper proposes a novel stochastic speed prediction method for connected vehicles by incorporating a Bayesian network(BN) and a Back Propagation(BP) neural network. A BN model is first designed for predicting the stochastic vehicular speed in a priori. To improve the accuracy of the BN-based speed prediction, a BP-based predicted speed error compensation module is constructed by formulating a mapping between the predicted speed and its corresponding prediction error. In the end, a filtering algorithm is developed to smoothen the compensated stochastic vehicular speed. To validate the workings of the proposed approaches in experiments, two typical scenarios are considered: one predecessor vehicle in a double-vehicle scenario and two predecessor vehicles in a multi-vehicle scenario. Simulation results under the considered scenarios demonstrate that the proposed BN-BP fusion method outperforms the BN-based method with respect to the root mean square error, standardized residuals, and R-squared, and the online prediction time of proposed fusion prediction can satisfy a real-time application requirement. The main highlighted contributions of this article are threefold:(1) We put forward an improved BN method, which is combined with a BP neural network, to construct a stochastic vehicular speed prediction method under connected driving;(2) different from existing methods, a unique interconnected framework that consists of a stochastic vehicular speed prediction module, a compensation module, and a speed smoothing module is proposed;(3) extensive simulation studies based on a set of evaluation metrics are illustrated to reveal the advantages and merits of the proposed approaches.

关键词： connected vehicles stochastic vehicular speed prediction Bayesian network back-propagation

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Melatonin decreases GSDME mediated mesothelial cell pyroptosis and prevents peritoneal fibrosis and ultrafiltration failure

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Science China(Life Sciences) 2024年第2期67卷 360-378页

作者： Hongxia Ruan Xuejuan Li Lina Zhou Zihan Zheng Rulin Hua Xu wang Yuan wang Yujie Fan Shuwen Guo lihua wang Shafiq ur Rahman Ziwei wang Yuyuan Wei Shuangyan Yu Rongzhi Zhang Qian Cheng Jie Sheng Xue Li Xiaoyan Liu Ruqiang Yuan Xiaoyan Zhang Lihong Chen Guowang Xu Youfei Guan Jing Nie Hongqiang Qin Feng Zheng Advanced Institute for Medical Sciences Dalian Medical UniversityDalian 116044China Department of Nephrology Second HospitalDalian Medical UniversityDalian 116023China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Chongqing International Institute for Immunology Chongqing 401320China Department of Nephrology Shenzhen HospitalSouthern Medical UniversityShenzhen 518101China Wuhu Hospital and Health Science Center East China Normal UniversityShanghai 200241China Peking University First Hospital Peking UniversityBeijing 100034China

Peritoneal fibrosis together with increased capillaries is the primary cause of peritoneal dialysis failure.Mesothelial cell loss is an initiating event for peritoneal fibrosis.We find that the elevated glucose concentrations in peritoneal dialysate drive mesothelial cell pyroptosis in a manner dependent on caspase-3 and Gasdermin E,driving downstream inflammatory responses,including the activation of macrophages.Moreover,pyroptosis is associated with elevated vascular endothelial growth factor A and C,two key factors in vascular angiogenesis and lymphatic vessel formation.GSDME deficiency mice are protected from high glucose induced peritoneal fibrosis and ultrafiltration failure.Application of melatonin abrogates mesothelial cell pyroptosis through a MT1R-mediated action,and successfully reduces peritoneal fibrosis and angiogenesis in an animal model while preserving dialysis efficacy.Mechanistically,melatonin treatment maintains mitochondrial integrity in mesothelial cells,meanwhile activating m TOR signaling through an increase in the glycolysis product dihydroxyacetone phosphate.These effects together with quenching free radicals by melatonin help mesothelial cells maintain a relatively stable internal environment in the face of high-glucose stress.Thus,Melatonin treatment holds some promise in preserving mesothelium integrity and in decreasing angiogenesis to protect peritoneum function in patients undergoing peritoneal dialysis.

关键词： melatonin mitochondria pyroptosis GSDME peritoneal fibrosis mTOR

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Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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National Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao lihua wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing Key Lab of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology Department of Materials Science and Engineering City University of Hong Kong Key Laboratory of Partial Acceleration Physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences Department of Materials Science &Engineering Southern University of Science and Technology Department of Physics City University of Hong Kong State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

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Confined Mn^(2+) enables effective aerobic oxidation catalysis

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Science China Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan Sicong Ma Xiao Kong Chi Zhang Lin Chen Chengsheng Yang lihua wang Zhen Liu Lin Ye Yongmei Liu Rui Ma Zhi-Pan Liu Yifeng Zhu Yong Cao Xinhe Bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing Materials Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and CO.The Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold further.The finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

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论数字经济背景下的全球税收正义及中国应对

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上海财经大学学报（哲学社会科学版） 2024年第1期26卷 108-123页

作者：王丽华上海政法学院国际法学院上海201701

随着全球数字经济税收治理方案的不断完善,全球税收治理进一步深化。由于全球税收治理价值指导着全球税收治理的方向,影响着国家的国际税收利益,因而全球税收治理价值问题引发了更多的关注。全球税收正义是全球税收治理所追求的价值,它... 详细信息

随着全球数字经济税收治理方案的不断完善,全球税收治理进一步深化。由于全球税收治理价值指导着全球税收治理的方向,影响着国家的国际税收利益,因而全球税收治理价值问题引发了更多的关注。全球税收正义是全球税收治理所追求的价值,它既是税收正义从一国向全球扩展的结果,也是全球正义在全球税收治理领域适用的结果。但当前全球税收正义在合法性、公平性方面均存在一定问题,这不仅影响了发展中国家在全球税改中的利益,也妨碍了全球税收治理善治的实现。在全球税收治理过程中,公平、民主和效率价值逐渐成为全球税收正义统领下构成正义的主要次级价值和重要支柱。中国应从理念、机制路径出发推进全球税收正义的构建,在理念路径方面,以人类命运共同体理念引领全球税收正义的构建;在机制路径方面,通过推动建立联合国为主导的全球税收治理机制、增强发展中国家在G20+OECD机制中的集体行动、发挥“一带一路”税收征管合作机制的作用来引导全球税收正义的构建,增强中国在全球税收治理领域的话语权和影响力。

关键词：数字经济全球税收治理全球税收正义内涵中国构建方案

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Theoretical analysis of a new segmented anchoring style in weakly cemented soft surrounding rock

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International Journal of Mining Science and Technology 2016年第3期26卷 401-407页

作者： Zhao Zenghui wang Weiming wang lihua Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science & Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science & Technology College of Mining and Safety Engineering Shandong University of Science & Technology College of Civil Engineering and Architecture Shandong University of Science & Technology

According to the tensile failure of rock bolt in weakly cemented soft rock, this paper presents a new segmented anchoring style in order to weaken the cumulative effect of anchoring force associated with the large deformation. Firstly, a segmented mechanical model was established in which free and anchoring section of rock bolt were respectively arranged in different deformation zones. Then, stress and displacement in elastic non-anchoring zone, elastic anchoring zone, elastic sticking zone, softening sticking zone and broken zone were derived respectively based on neural theory and tri-linear strain softening constitutive model of soft rock. Results show that the anchoring effect can be characterized by a supporting parameter b. With its increase, the peak value of tangential stress gradually moves to the roadway wall, and the radial stress significantly increases, which means the decrease of equivalent plastic zone and improvement of confining effect provided by anchorage body. When b increases to 0.72, the equivalent plastic zone disappears, and stresses tend to be the elastic solutions. In addition, the anchoring effect on the displacement of surrounding rock can be quantified by a normalization factor δ.

关键词：锚固方式分段软岩围岩胶结等效塑性区岩石锚杆应变软化

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科学合作视角下的数字人文学科交叉测度——基于ADHO年会的研究

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图书馆杂志 2024年第2期43卷 84-95,108页

作者：王丽华王义菊上海大学文化遗产与信息管理学院上海200444

数字人文是数字技术与人文学科交叉融合而形成的新兴跨学科研究领域,是学科交叉融合的典范,把握其学科交叉特征有助于理解数字人文学科内涵,而从科学合作视角下对其进行学科交叉测度,为数字人文学科交叉量化研究提供了一种新的思路,也... 详细信息

数字人文是数字技术与人文学科交叉融合而形成的新兴跨学科研究领域,是学科交叉融合的典范,把握其学科交叉特征有助于理解数字人文学科内涵,而从科学合作视角下对其进行学科交叉测度,为数字人文学科交叉量化研究提供了一种新的思路,也为解释数字人文学科交叉融合现象提供了科学依据。文章从具有代表性的数字人文会议切入,选取ADHO数字人文年会成果为研究对象,通过基于合作者机构信息的交叉科学测度方法,对数字人文的学科交叉程度进行测度分析。测度研究结果表明数字人文具备文理融合特征,是一个跨学科性极强的综合性学科领域,各学科之间交叉的广度和深度不断提高,逐渐从早期相近学科之间的交叉转向非相近学科之间的交叉。

关键词：数字人文学科交叉跨学科测度 ADHO

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意义的再生产:信息稳定视角下新闻发布会的四要素分析

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江西师范大学学报（哲学社会科学版） 2024年第1期57卷 81-92页

作者：邱新有王丽华江西师范大学新闻与传播学院江西南昌330022 江西师范大学文学院江西南昌330022

信息稳定包含信息传播的时间、内容、结构和流量,四个维度的合理把控与社会秩序稳定存在较大的关联度。作为信息传播的重要渠道之一,新闻发布会与信息稳定的关系是值得探讨的议题。具体而言,距离事发时间越近,越有利于舆论引导;距离舆... 详细信息

信息稳定包含信息传播的时间、内容、结构和流量,四个维度的合理把控与社会秩序稳定存在较大的关联度。作为信息传播的重要渠道之一,新闻发布会与信息稳定的关系是值得探讨的议题。具体而言,距离事发时间越近,越有利于舆论引导;距离舆论沸腾时间越近,越有利于事件平息。信息内容与事件、角色、时态和发言人相关联,并与民众间的信任关系成正比。越以政府为中心,信息结构越趋于正面信息,越以民众为中心,则趋于正负信息结合。信息发布量是影响社会稳定的重要因素,由宏观层面的新闻发布制度和微观层面的会话规则共同把控。新闻发布会四要素的合理安排,是在社会范围内实现意义再生产,推动政治秩序从无序到有序的重要环节。

关键词：新闻发布会信息稳定传播仪式信任

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数字基础设施建设对城市绿色创新效率的影响——基于“宽带中国”战略试点政策的准自然实验

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工业技术经济 2024年第2期43卷 152-160页

作者：刘军王励铧山西财经大学国际贸易学院太原030006 山西财经大学资源型经济转型发展研究院太原030006

本文基于我国280个地级及以上城市2006~2021年的面板数据,利用多期双重差分模型考察“宽带中国”战略试点政策实施对城市绿色创新效率的影响效应、内在机制及异质性表现。研究发现:(1)“宽带中国”战略试点政策实施对城市绿色创新效率... 详细信息

本文基于我国280个地级及以上城市2006~2021年的面板数据,利用多期双重差分模型考察“宽带中国”战略试点政策实施对城市绿色创新效率的影响效应、内在机制及异质性表现。研究发现:(1)“宽带中国”战略试点政策实施对城市绿色创新效率具有显著的提升作用,并且在一系列稳健性检验后结果依然稳健;(2)劳动力流动和生产性服务业集聚是“宽带中国”战略试点政策实施提高城市绿色创新效率的两种机制;(3)“宽带中国”战略试点政策实施对城市绿色创新效率的促进作用在东部城市、大规模城市、非资源型城市中更强;(4)正式环境规制和非正式环境规制正向调节“宽带中国”战略试点政策实施对城市绿色创新效率的驱动作用。本文为推动数字基础设施建设以及城市绿色创新效率的提升提供了重要政策启示。

关键词：数字基础设施建设 “宽带中国” 城市绿色创新效率环境规制劳动力流动生产性服务业集聚

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