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Flow characteristics of radial inflow in impeller rear cavity with baffle plate

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Chinese Journal of Aeronautics 2024年第2期37卷 270-282页

作者： Yang BAI Xiang LUO Dongdong LIU Zeyu WU xiaoqiang zhang Sipeng WANG Research Institute of Aero-Engine Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

The research purpose of this paper is to explore the influence of the baffle plate on the airflow in the rear cavity of the centrifugal impeller and optimize the performance of the secondary air system’s air bleed section.In this paper,a comprehensive experimental study was carried out on the flow characteristics in the impeller rear cavity with baffle plate.The windage torque,flow structure and pressure drop between inlet and outlet were measured respectively.The experiment was carried out with the condition that the range of rotational Reynolds number was from 8.33×10^(5)to 22.2×10^(5)and the range of mass flow rate coefficient was from 0.92×10^(4)to 2.92×10^(4).The results show that the static cavity and the narrow stator-rotor cavity formed by the baffle plate effectively suppress the overall swirl coefficient in the cavity.Thus,the static pressure and total pressure drop in the rotor-stator cavity were reduced.The influence of the baffle plate on the windage torque of the rotary disk is related to the turbulence parameters.Under large turbulence parameters,the windage torque would be reduced with baffle plate,while under small turbulence parameters,the baffle plate would increase with baffle plate.In general,the baffle plate can improve the flow capacity and optimize the bleed air performance with proper structure and operation conditions.

关键词： Impeller rear cavity Baffle plate Flow structure Windage torque Pressure drop

Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： xiaoqiang Wang Zhiwei Wu Bing Li Wenxiong Chen Jun zhang Jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China Chengdu Advanced Metal Materials Industry Technology Research Institute Co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE content(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative contents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Second, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the corrosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

An Adaptive Control Strategy for Energy Storage Interface Converter Based on Analogous Virtual Synchronous Generator

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Energy Engineering 2024年第2期121卷 339-358页

作者： Feng Zhao Jinshuo zhang xiaoqiang Chen Ying Wang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou730070China

In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power.To address this issue,the application of a virtual synchronous generator(VSG)in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator(AVSG)control strategy for the interface DC/DC converter of the battery in the microgrid.Besides,a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of the AVSG control.Firstly,a theoretical analysis is conducted on the various components of the DC microgrid,the structure of analogous virtual synchronous generator,and the control structure’s main parameters related to the DC microgrid’s inertial behavior.Secondly,the voltage change rate tracking coefficient is introduced to adjust the change of the virtual capacitance and damping coefficient flexibility,which further strengthens the inertia trend of the DC microgrid.Additionally,a small-signal modeling approach is used to analyze the approximate range of the AVSG’s main parameters ensuring system stability.Finally,conduct a simulation analysis by building the model of the DC microgrid system with photovoltaic(PV)and battery energy storage(BES)in MATLAB/Simulink.Simulation results from different scenarios have verified that the AVSG control introduces fixed inertia and damping into the droop control of the battery,resulting in a certain level of inertia enhancement.Furthermore,the additional adaptive control strategy built upon the AVSG control provides better and flexible inertial support for the DC microgrid,further enhances the stability of the DC bus voltage,and has a more positive impact on the battery performance.

关键词： Adaptive control analogous virtual synchronous generator DC/DC converter inertia of DC microgrid DC microgrid with PV and BES battery DC bus voltage

Kinetically and thermodynamically expediting elementary steps via high-valence Cr-incorporated of nickel selenide for water electrolysis

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Nano Research 2024年第3期17卷 1199-1208页

作者： Huafeng Fan Dongxu Jiao Jinchang Fan Dewen Wang Bilal Zaman Wei zhang Lei zhang Weitao Zheng xiaoqiang Cui State Key Laboratory of Automotive Simulation and Control School of Materials Science and EngineeringKey Laboratory of Automobile Materials of MOEJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsElectron Microscopy CenterJilin UniversityChangchun 130012China College of Chemistry Jilin UniversityChangchun 130012China

Designing high-performance electrocatalysts toward hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is essential to reduce the activation barrier and optimize free adsorption energy of reactive intermediates.Herein,we report that incorporating high-valence Cr into NiSe_(2)(Cr_(x)Ni_(1-x)Se_(2))kinetically and thermodynamically expedites elementary steps of both HER and OER.The as-prepared Cr_(0.05)Ni_(0.95)Se_(2) catalyst displays excellent HER and OER activities,with low overpotentials of 89 and 272 mV at the current density of 10 mA·cm^(-2)(j10),respectively,and remains stable during operation for 30 h.A low cell voltage of only 1.59 V is required to drive j10 in alkaline media.In situ Raman spectroscopy reveals that Cr incorporation facilitates the formation of NiOOH active species during the OER process.Meanwhile,theoretical explorations demonstrate that high-valence Cr incorporation efficiently accelerates water dissociation kinetics and improves H*adsorption during HER process,lowering the activation barrier of OER and optimizing the adsorption energy of oxygen-based intermediate,thus kinetically and thermodynamically enhancing the intrinsic performance of NiSe_(2) for over water splitting.This strategy provides a new horizon to design transition metal based electrocatalysts in the clean energy field.

关键词： nickel selenide electrocatalytic water splitting high-valence Cr density functional theory(DFT)calculation

Promotion effect of FOXCUT as a microRNA sponge for miR-24-3p on progression in triple-negative breast cancer through the p38 MAPK signaling pathway

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Chinese Medical Journal 2024年第1期137卷 105-114页

作者： Xiafei Yu Fangze Qian xiaoqiang zhang Yanhui Zhu Gao He Junzhe Yang Xian Wu Yi Zhou Li Shen Xiaoyue Shi Hongfei zhang Xiao’an Liu Department of Breast Surgery The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China

Background:Triple-negative breast cancer(TNBC)is a type of highly invasive breast cancer with a poor prognosis.According to new research,long noncoding RNAs(lncRNAs)play a significant role in the progression of cancer.Although the role of lncRNAs in breast cancer has been well reported,few studies have focused on TNBC.This study aimed to explore the biological function and clinical significance of forkhead box C1 promoter upstream transcript(FOXCUT)in triple-negative breast cancer.Methods:Based on a bioinformatic analysis of the cancer genome atlas(TCGA)database,we detected that the lncRNA FOXCUT was overexpressed in TNBC tissues,which was further validated in an external cohort of tissues from the General Surgery Department of the First Affiliated Hospital of Nanjing Medical University.The functions of FOXCUT in proliferation,migration,and invasion were detected in vitro or in vivo.Luciferase assays and RNA immunoprecipitation(RIP)were performed to reveal that FOXCUT acted as a competitive endogenous RNA(ceRNA)for the microRNA miR-24-3p and consequently inhibited the degradation of p38.Results:lncRNA FOXCUT was markedly highly expressed in breast cancer,which was associated with poor prognosis in some cases.Knockdown of FOXCUT significantly inhibited cancer growth and metastasis in vitro or in vivo.Mechanistically,FOXCUT competitively bounded to miR-24-3p to prevent the degradation of p38,which might act as an oncogene in breast cancer.Conclusion:Collectively,this research revealed a novel FOXCUT/miR-24-3p/p38 axis that affected breast cancer progression and suggested that the lncRNA FOXCUT could be a diagnostic marker and therapeutic target for breast cancer.

关键词： Triple negative breast neoplasms RNA,long noncoding FOXCUT miR-24-3p p38 MAPK signaling pathway Disease progression

Hepatic Zbtb18 (Zinc Finger and BTB Domain Containing 18) alleviates hepatic steatohepatitis via FXR (Farnesoid X Receptor)

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Signal Transduction and Targeted Therapy 2024年第2期9卷 766-781页

作者： Lei zhang Jiabing Chen Xiaoying Yang Chuangpeng Shen Jiawen Huang Dong zhang Naihua Liu Chaonan Liu Yadi Zhong Yingjian Chen Kaijia Tang Jingyi Guo Tianqi Cui Siwei Duan Jiayu Li Shangyi Huang Huafeng Pan Huabing zhang xiaoqiang Tang Yongsheng Chang Yong Gao State Key Laboratory of Traditional Chinese Medicine Syndrome Science and Technology Innovation CenterGuangzhou University of Chinese MedicineGuangzhouChina Key Laboratory of Immune Microenvironment and Disease(Ministry of Education) Tianjin Key Laboratory of Cellular Homeostasis and DiseaseDepartment of Physiology and PathophysiologyTianjin Medical UniversityTianjinChina Jiangsu Key Laboratory of Immunity and Metabolism Department of Pathogen Biology and ImmunologyJiangsu International Laboratory of Immunity and MetabolismXuzhou Medical UniversityXuzhouChina Department of Endocrinology The First Clinical CollegeGuangzhou University of Chinese MedicineGuangdongChina The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine ShenzhenChina Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing University of Chinese MedicineNanjingChina Department of Biochemistry and Molecular Biology Metabolic Disease Research CenterSchool of Basic MedicineAnhui Medical UniversityHefeiChina Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE State Key Laboratory of BiotherapyWest China Second University HospitalSichuan UniversityChengduChina

A lasting imbalance between fatty acid synthesis and consumption leads to non-alcoholic fatty liver disease(NAFLD),coupled with hepatitis and insulin resistance.Yet the details of the underlying mechanisms are not fully understood.Here,we unraveled that the expression of the transcription factor Zbtb18 is markedly decreased in the livers of both patients and murine models of NAFLD.Hepatic Zbtb18 knockout promoted NAFLD features like impaired energy expenditure and fatty acid oxidation(FAO),and induced insulin resistance.Conversely,hepatic Zbtb18 overexpression alleviated hepato-steatosis,insulin resistance,and hyperglycemia in mice fed on a high-fat diet(HFD)or in diabetic mice.Notably,in vitro and in vivo mechanistic studies revealed that Zbtb18 transcriptional activation of Farnesoid X receptor(FXR)mediated FAO and Clathrin Heavy Chain(CLTC)protein hinders NLRP3 inflammasome activity.This key mechanism by which hepatocyte’s Zbtb18 expression alleviates NAFLD and consequent liver fibrosis was further verified by FXR’s deletion and forced expression in mice and cultured mouse primary hepatocytes(MPHs).Moreover,CLTC deletion significantly abrogated the hepatic Zbtb18 overexpression-driven inhibition of NLRP3 inflammasome activity in macrophages.Altogether,Zbtb18 transcriptionally activates the FXR-mediated FAO and CLTC expression,which inhibits NLRP3 inflammasome’s activity alleviating inflammatory stress and insulin resistance,representing an attractive remedy for hepatic steatosis and fibrosis.

关键词： hepatic Hepatic impaired

不确定需求下铁路集装箱班列开行方案与定价联合优化

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铁道学报 2024年第1期46卷 22-33页

作者：李琳张小强上海海事大学交通运输学院上海201306 西南交通大学交通运输与物流学院四川成都611756 西南交通大学综合交通大数据应用技术国家工程实验室四川成都611756 西南交通大学综合交通运输智能化国家地方联合工程实验室四川成都611756

铁路集装箱班列开行方案与运价是影响铁路集装箱运输企业盈利的两个关键因素,且这二者相互联系、相互影响,对其进行联合优化可以提升铁路集装箱运输的市场竞争力。以最大化铁路集装箱运输预期利润为目标,构建联合优化班列开行方案与定... 详细信息

铁路集装箱班列开行方案与运价是影响铁路集装箱运输企业盈利的两个关键因素,且这二者相互联系、相互影响,对其进行联合优化可以提升铁路集装箱运输的市场竞争力。以最大化铁路集装箱运输预期利润为目标,构建联合优化班列开行方案与定价的随机混合整数非线性规划(SMINP)模型。此模型以二项Logit模型描述托运人在铁路集装箱运输与公路集装箱运输之间的运输方式选择行为,在集装箱总运输需求概率分布形式、一阶矩与二阶矩均不确定的情形下,基于分布鲁棒优化方法将此SMINP模型转化为其确定性等价类,根据转化后模型特点进一步利用增量分段线性化以及McCormick包络法对模型线性化,使其可通过调用Gurobi求解器高效求解。以大朗至大红门铁路集装箱运输线路进行算例分析,在线路通过能力与运价可变动范围等信息已知的前提下,求得最优集装箱班列开行方案与运价。算例结果表明本文所提方法能够提升铁路集装箱运输效率与收益。

关键词：铁路集装箱运输开行方案定价分布鲁棒机会约束线性化

Agriculture green development in China: insights and advances

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 5-19,I0005页

作者： Jianbo SHEN Qichao ZHU Yong HOU Wen-Feng CONG Wen XU Jiuliang XU Zhichao AN xiaoqiang JIAO Kai zhang Tianxiang YU Lin MA Oene OENEMA William J.DAVIES Fusuo zhang State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Wageningen Environmental Research Wageningen University&ResearchWageningen6700 AAthe Netherlands Lancaster Environment Centre University of LancasterLancasterLA14YQUK

Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.

关键词： Agriculture ecosystem services environmental protection food security green development multi-sectoral cooperation sustainable development

Atomic Dispersed Hetero‑Pairs for Enhanced Electrocatalytic CO_(2)Reduction

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Nano-Micro Letters 2024年第1期16卷 55-67页

作者： Zhaoyong Jin Meiqi Yang Yilong Dong Xingcheng Ma Ying Wang Jiandong Wu Jinchang Fan Dewen Wang Rongshen Xi Xiao Zhao Tianyi Xu Jingxiang Zhao Lei zhang David J.Singh Weitao Zheng xiaoqiang Cui State Key Laboratory of Automotive Simulation and Control School of Materials Science and EngineeringKey Laboratory of Automobile Materials of MOEElectron Microscopy CenterJilin UniversityChangchun 130012People’s Republic of China Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of Educationand College of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025People’s Republic of China College of Chemistry Jilin UniversityChangchun 130012People’s Republic of China Department of Physics and Astronomy and Department of Chemistry University of MissouriColumbiaMO 65211USA

Electrochemical carbon dioxide reduction reaction(CO_(2)RR)involves a variety of intermediates with highly correlated reaction and ad-desorption energies,hindering optimization of the catalytic activity.For example,increasing the binding of the*COOH to the active site will generally increase the*CO desorption energy.Breaking this relationship may be expected to dramatically improve the intrinsic activity of CO_(2)RR,but remains an unsolved challenge.Herein,we addressed this conundrum by constructing a unique atomic dispersed hetero-pair consisting of Mo-Fe di-atoms anchored on N-doped carbon carrier.This system shows an unprecedented CO_(2)RR intrinsic activity with TOF of 3336 h−1,high selectivity toward CO production,Faradaic efficiency of 95.96%at−0.60 V and excellent stability.Theoretical calculations show that the Mo-Fe diatomic sites increased the*COOH intermediate adsorption energy by bridging adsorption of*COOH intermediates.At the same time,d-d orbital coupling in the Mo-Fe di-atom results in electron delocalization and facilitates desorption of*CO intermediates.Thus,the undesirable correlation between these steps is broken.This work provides a promising approach,specifically the use of di-atoms,for breaking unfavorable relationships based on understanding of the catalytic mechanisms at the atomic scale.

关键词： CO_(2)reduction reaction Atomic dispersed catalyst Hetero-diatomic pair Ad-desorption energy Linear scaling relation