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1979-2020年中国油菜全要素生产率的动态演变与收敛性

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中国油料作物学报 2024年第2期46卷 236-244页

作者：刘福星王彩丽唐晶冯中朝华中农业大学经济管理学院湖北武汉430070 湖北农村发展研究中心湖北武汉430070

厘清改革开放以来中国油菜全要素生产率发展状况,是提高油菜综合生产能力的逻辑起点。本文基于1979-2020年间11个油菜主产省份的投入产出相关数据,在使用Global Malmquist指数测算全要素生产率基础上,分别使用Kernel密度估计、δ收敛和... 详细信息

厘清改革开放以来中国油菜全要素生产率发展状况,是提高油菜综合生产能力的逻辑起点。本文基于1979-2020年间11个油菜主产省份的投入产出相关数据,在使用Global Malmquist指数测算全要素生产率基础上,分别使用Kernel密度估计、δ收敛和β收敛,分析其动态演进及收敛性。研究结果表明:从时序特征来看,改革开放以来中国油菜全要素生产率在剧烈波动中实现一定增长,表现为技术诱导型增长模式,而技术效率对其促进作用并不显著;从动态演进来看,油菜全要素生产率增长的地区差异不断缩小。从收敛性来看,油菜全要素生产率的δ值整体呈波动下降态势,自2012年始基本稳定在0.01以下,出现明显收敛趋势,说明存在δ收敛。油菜全要素生产率存在绝对β收敛和条件β收敛,将空间效应引入收敛模型后,其收敛性依旧显著,且存在正向空间溢出效应。为进一步提高油菜全要素生产率,本文提出推进国家油菜产业技术体系建设、实施区域化发展战略和促进区域协调发展的对策建议。

关键词：油菜全要素生产率动态演变 Kernel密度估计 δ收敛 β收敛

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Effect of Slope Degree on the Lateral Bending in Gekko geckos

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Journal of Bionic Engineering 2015年第2期12卷 238-249页

作者： Zhouyi wang Lei cai Wei li Aihong Ji Wenbo wang Zhendong Dai Institute of Bio-Inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A gecko＇s habitat possesses a wide range of climbing slopes that pose a number of postural challenges for climbing lo- comotion. Few studies have examined the relationship between the lateral bending of the trunk of a gecko and other aspects of locomotion when climbing. In this paper, three-dimensional reaction forces and high-speed videos of Gekko geckos moving on different slopes are used to reveal how the lateral bending of the animal＇s trunk responds to changing slopes. The results of such observations indicate that the minimum bending radius continually decreases with an increase in the slope, illustrating that the degree of bending of the trunk becomes significantly greater. Moreover, a lateral bending mechanical model is used to show the interrelation between the lateral bending in the frontal plane and the sagittal deformation of the trunk caused by gravity. Taken together, these results have advanced our understanding of the role of lateral bending of vertebrates when climbing on a slope.

关键词： slope lateral bending reaction force gecko ceiling

细胞自噬在局灶节段性肾小球硬化中的研究进展

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临床肾脏病杂志 2024年第8期24卷 677-680页

作者：张敏米焱王彩丽内蒙古科技大学包头医学院包头医学院第一附属医院内科包头014010 内蒙古科技大学包头医学院包头医学院第一附属医院肾内科包头014010

局灶节段性肾小球硬化(focal segmental glomerulosclerosis,FSGS)是伴有大量蛋白尿的临床病理综合征,以局灶肾小球硬化和足细胞足突消失为特征。现研究已证实足细胞损伤是FSGS发病的核心,且越来越多的研究表明氧化应激、炎症、近端小... 详细信息

局灶节段性肾小球硬化(focal segmental glomerulosclerosis,FSGS)是伴有大量蛋白尿的临床病理综合征,以局灶肾小球硬化和足细胞足突消失为特征。现研究已证实足细胞损伤是FSGS发病的核心,且越来越多的研究表明氧化应激、炎症、近端小管上皮细胞(proximal tubule epithelial cells,PTECs)和肾小球内皮细胞(glomerular endothelial cells,GECs)的紊乱有助于FSGS的发展。近年来自噬在诸多研究领域备受瞩目,许多证据表明自噬在FSGS中发挥着重要的调控作用,这也为FSGS的治疗提供了一个新靶点,本文就自噬及其在FSGS中的作用做一综述。

关键词：局灶节段性肾小球硬化自噬 mTORC1 ATG

基于源网荷储协同控制系统稳控测试技术研究及应用

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电工电气 2024年第10期 47-52页

作者：王彩丽徐兴豫张文陈晨王振谷威河南源网荷储电气研究院有限公司河南许昌461000

以某新型电力系统示范应用工程为切入点,介绍了该工程稳控系统的架构形式及系统各层级装置配置和控制策略;列出了各层级之间通信协议及方案,并结合通信方案及策略设计了合理的测试方案及用例。通过搭建仿真实验平台,实现了稳控系统边界... 详细信息

以某新型电力系统示范应用工程为切入点,介绍了该工程稳控系统的架构形式及系统各层级装置配置和控制策略;列出了各层级之间通信协议及方案,并结合通信方案及策略设计了合理的测试方案及用例。通过搭建仿真实验平台,实现了稳控系统边界测试及自动测试,结果表明,自动测试系统明显提升了自动化程度、测试效率及测试的全面性,测试用例的可无限重复执行提升了发现小概率问题的几率。

关键词：新型电力系统源网荷储协同控制系统稳控系统控制策略自动测试边界测试

体外受精-胚胎移植屈螺酮炔雌醇预处理对多囊卵巢综合征妊娠结局的影响

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海南医学 2024年第6期35卷 799-803页

作者：王彩丽刘瑞敏陈雨露周口市中心医院生殖医学中心河南周口466000

目的探讨体外受精-胚胎移植(IVF-ET)屈螺酮炔雌醇预处理对多囊卵巢综合征(PCOS)患者妊娠结局的影响。方法回顾性分析2022年3月至2023年4月周口市中心医院收治的70例PCOS患者的临床资料,按照治疗方法不同分组,其中36例在IVF-ET治疗前未... 详细信息

目的探讨体外受精-胚胎移植(IVF-ET)屈螺酮炔雌醇预处理对多囊卵巢综合征(PCOS)患者妊娠结局的影响。方法回顾性分析2022年3月至2023年4月周口市中心医院收治的70例PCOS患者的临床资料,按照治疗方法不同分组,其中36例在IVF-ET治疗前未使用屈螺酮炔雌醇处理者纳入对照组,34例在IVF-ET治疗前使用屈螺酮炔雌醇处理者纳入观察组。治疗3个周期后,比较两组患者的妊娠结局,以及治疗前后的性激素水平、子宫内膜厚度、窦卵细胞数目、卵巢体积、胰岛素指数、胰岛素抵抗指数,同时比较两组患者的不良反应发生情况。结果治疗后,观察组患者的临床妊娠率为67.65%,高于对照组的52.78%,流产率和异位妊娠率分别为2.94%、2.94%,低于对照组的8.33%、5.56%,但差异均无统计学意义(P>0.05)。治疗前,两组患者的促性腺激素血清促卵泡刺激素(FSH)、促黄体生成素(LH)、睾酮(T)、雌二醇(E2)、抗苗勒氏管激素(AMH)水平比较差异均无统计学意义(P>0.05);治疗3个周期后,对照组患者的FSH、T、AMH高于治疗前,LH、E2低于治疗前,但差异无统计学意义(P>0.05);治疗3个周期后,观察组患者的FSH、AMH水平均高于治疗前且明显高于对照组,LH、T、E2水平低于治疗前且明显低于对照组,差异均有统计学意义(P0.05)。结论PCOS患者IVF-ET治疗前使用屈螺酮炔雌醇处理可显著改善患者的性激素水平,增加其子宫内膜厚度和卵巢体积,从而改善妊娠结局。

关键词：多囊卵巢综合征体外受精-胚胎移植屈螺酮炔雌醇预处理妊娠结局

Microstructure and Shear Properties Evolution of Minor Fe-Doped SAC/Cu Substrate Solder Joint under Isothermal Aging

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1279-1290页

作者： Quanzhen li Chengming li Xiaojing wang Shanshan cai Jubo Peng Shujin Chen Jiajun wang Xiaohong Yuan Jiangsu University of Science and Technology Zhenjiang212003China R&D Center Yunnan Tin Group(Holding)Co.LtdKunming650000China The 58 Research Institute of China Electronics Technology Group CorporationWuxi214100China Yunnan Precious Metals Lab Sino-Platinum Metals Co.LtdKunming650156China

Different amounts of Fe(0.005,0.01,0.03,0.05,and 0.07 wt%)were added to SAC305 to study the shear behavior damage of Fe-doped SAC solder joints under thermal loading(170℃,holding time of 0,250,500,and 750 h).The results show that during isothermal aging at 170℃,the average shear force of all solder joints decreases with increasing aging time,while the average fracture energy first increases and then decreases,reaching a maximum at 500 *** Fe doping could both increase shear forces and related fracture energy,with the optimum Fe doping amount being 0.03 wt%within the entire aging *** is because the doping Fe reduces the undercooling of the SAC305 alloy,resulting in the microstructure refining of solder *** in turn causes the microstructure changing from network structure(SAC305 joint:eutectic network+β-Sn)to a single matrix structure(0.03Fe-doped SAC305 joint:β-Sn matrix+small compound particles).Specifically,Fe atoms can replace some Cu in Cu_(6)Sn_(5)(both inside the solder joint and at the interface),and then form(Cu,Fe)_(6)Sn_(5) compounds,resulting in an increase in the elastic modulus and nanohardness of the ***,the growth of Cu_(6)Sn_(5) and Cu_(3)Sn intermetallic compounds(IMC)layer are inhibited by Fe doping even after the aging time prolonging,and Fe aggregates near the interface compound to form FeSn_(2).This study is of great significance for controlling the growth of interfacial compounds,stabilizing the microstructures,and providing strengthening strategy for solder joint alloy design.

关键词： SAC305 solder Fe doping Shear mechanical behavior Isothermal aging Interfacial intermetallic compounds(IMC)

Upgrading waste NO_(x) into amino acids via electrocatalysis on Co nanoparticles encapsulated in hollow carbon nanofibers

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Science China Chemistry 2024年第6期67卷 1946-1952页

作者： Jiahui Xian Kaixing cai Peisen liao Shihan wang Guangqin li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education LIFMIGCMESchool of ChemistrySun Yat-Sen UniversityGuangzhou510275China

Electrocatalytic conversion of waste nitrogen oxide(NO_(x))into value-added nitrogenous chemicals,especially amino acid,is an emerging strategy to alleviate NO_(x)***,this process suffers from the coexistence of multiple competitive reactions leading to complex product distribution and low efficiency,and thus the rational design and modulation of efficient catalysts remains a formidable ***,well-designed Co nanoparticles encapsulated in hollow carbon nanofiber(CoHCNF)were constructed to promote the amino acid electrosynthesis via dealing waste NO_(x)coupling with biomass-derived keto *** to the rapid reactant diffusion,electron transport and efficient contact with abundant accessible Co catalytic sites stemmed from the unique hollow nanotubular structure,Co-HCNF manifested impressive glycine synthesis performance in one-pot adopting NO as the nitrogen source with Faradaic efficiency(FE)of 41.7%and a corresponding yield rate of 222.3μmol h^(-1)as well as 120 h robust ***,it also demonstrates an excellent performance with the FE of 42.8%for NO_(3)~-solution as the nitrogen ***,this strategy displays a broad universality for the synthesis of other amino *** work not only highlights the importance of hollow-structuring electrocatalyst towards upgrading wasted NO_(x)species into amino acids,but also promotes the further development of electrosynthetic systems for high-valued N-containing organic chemicals.

关键词： electrocatalysis NO_(x)reduction amino acid porous materials hollow structure

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

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Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian li Zi-Jie lin liu Yang Yue wang Yue li Wei-Hua cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： Xuan-Hong cai Zhen-Hua wang Ben Niu Jin-Feng li Qing wang Show authors Key Laboratory of Materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy