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国内国际双循环与出口产品质量

商业经济与管理 2024年第8期 5-20页

作者：戴翔华笑烨南京审计大学统计与数据科学学院江苏南京211815

基于引入出口产品质量的异质性企业模型并进行适当拓展,文章从“量”和“畅”的双重维度,理论阐释国内国际双循环如何影响出口产品质量。研究表明:第一,国内国际双循环“量”及二者交互作用,能够显著促进出口产品质量升级。第二,对于不... 详细信息

基于引入出口产品质量的异质性企业模型并进行适当拓展,文章从“量”和“畅”的双重维度,理论阐释国内国际双循环如何影响出口产品质量。研究表明:第一,国内国际双循环“量”及二者交互作用,能够显著促进出口产品质量升级。第二,对于不同地区,以及不同出口目的国,国内国际双循环“量”提升出口产品质量的效果存在显著差异。第三,国内国际双循环“量”对出口产品质量的提升具有单门槛效应,随着双循环相互促进水平提高,其对出口产品质量提升的弹性系数也越高。第四,畅通程度对经济循环“量”的作用发挥具有显著影响,具体而言,国内循环之“畅”不仅影响了国内循环“量”对出口产品质量升级的促进作用,还透过国际循环阻碍了出口产品质量升级。研究结论对于如何从“量”和“畅”的双重维度,真正发挥“双循环”重塑出口竞争新优势具有重要政策含义。

关键词：双循环畅通出口产品质量

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空间溢出效应、内循环畅通与出口产品质量升级

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国际贸易问题 2024年第7期 37-53页

作者：戴翔华笑烨南京审计大学统计与数据科学学院南京审计大学经济学院

本文基于马尔科夫转移概率矩阵和空间莫兰指数等进行的特征事实分析发现,中国出口产品质量存在显著的空间溢出效应。进一步引入出口产品质量的异质性企业模型分析得出,内循环畅通不仅对出口产品质量升级具有直接效应,而且省际循环畅通... 详细信息

本文基于马尔科夫转移概率矩阵和空间莫兰指数等进行的特征事实分析发现,中国出口产品质量存在显著的空间溢出效应。进一步引入出口产品质量的异质性企业模型分析得出,内循环畅通不仅对出口产品质量升级具有直接效应,而且省际循环畅通水平还会通过空间溢出效应而对出口产品质量产生间接影响。在创新性地对省内和省际循环畅通水平进行科学有效测度的基础上,本文基于空间计量模型开展实证研究,结果表明,在省内和省际循环畅通水平对出口产品质量起到显著提升作用的同时,省际循环畅通还表现出显著的出口产品质量空间溢出效应。上述结论在以市场分割作为省际循环畅通表征变量的进一步分析中也得到了证实。此外,异质性检验结果表明,省际循环畅通水平的出口产品质量空间溢出效应在东部地区和大规模省市最为显著。本研究对于畅通内循环进而更好发挥空间溢出效应,探寻贸易强国之路具有重要政策含义。

关键词：出口产品质量内循环畅通空间溢出市场分割

分析师的疲劳、预测质量与股票收益——来自中国资本市场的证据

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商业研究 2024年第3期 142-152页

作者：华夏樊力尹响西南财经大学金融学院成都611130 四川大学商学院成都610064

分析师的决策疲劳是否导致预测质量下降是业界关注的问题,本文对中国A股市场中分析师疲劳与预测质量关系进行研究,经过对2006—2023年A股市场卖方分析师个股研究报告中的盈余预测进行数据统计和分析,研究发现:分析师的决策疲劳与盈余预... 详细信息

分析师的决策疲劳是否导致预测质量下降是业界关注的问题,本文对中国A股市场中分析师疲劳与预测质量关系进行研究,经过对2006—2023年A股市场卖方分析师个股研究报告中的盈余预测进行数据统计和分析,研究发现:分析师的决策疲劳与盈余预测误差呈正向关系,即随着一周内发布预测的增加,分析师对公司盈余预测误差也在增大。分析师在决策疲劳严重时发布的预测会预示着未来个股中长期收益降低,盈余预测误差在这一关系中充当部分中介变量。决策疲劳引起的较低股票收益与市场信息不对称相关。

关键词：分析师预测盈余预测误差决策疲劳股票市场

Three-dimensional magnetic reconnection in complex multiple X-point configurations in an ancient solar-lunar terrestrial system

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Chinese Physics B 2024年第3期33卷 488-495页

作者：何向磊毛傲华孙萌萌邹继同王晓钢 School of Physics Harbin Institute of TechnologyHarbin 150001China Laboratory for Space Environment and Materials Science Harbin Institute of TechnologyHarbin 150001China

Magnetic reconnection processes in three-dimensional(3D)complex field configurations have been investigated in different magneto-plasma systems in space,laboratory,and astrophysical ***-dimensional(2D)features of magnetic reconnection have been well developed and applied successfully to systems with symmetrical property,such as toroidal fusion plasmas and laboratory experiments with an axial *** in asymmetric systems,the 3D features are inevitably different from those in the 2D *** reconnection structures in multiple celestial body systems,particularly star-planet-Moon systems,bring fresh insights to the understanding of the 3D geometry of ***,we take magnetic reconnection in an ancient solar-lunar terrestrial magneto-plasma system as an example by using its crucial parameters approximately estimated already and also some specific applications in pathways for energy and matter transports among Earth,ancient Moon,and the interplanetary magnetic field(IMF).Then,magnetic reconnection of the ancient lunar-terrestrial magnetospheres with the IMF is investigated numerically in this *** a 3D simulation for the Earth-Moon-IMF system,topological features of complex magnetic reconnection configurations and dynamical characteristics of magnetic reconnection processes are *** is found that a coupled lunar-terrestrial magnetosphere is formed,and under various IMF orientations,multiple X-points emerge at distinct locations,showing three typical magnetic reconnection structures in such a geometry,i.e.,the X-line,the triple current sheets,and the A-B null *** results can conduce to further understanding of reconnection physics in 3D for plasmas in complex magnetic configurations,and also a possible mechanism for energy and matters transport in evolutions of similar astrophysical systems.

关键词： magnetic reconnection multiple X-points complex magneto-plasma system

One-shot synthesis of heavy-atom-modified carbazole-fused multi-resonance thermally activated delayed fluorescence materials

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Science China Materials 2024年第9期67卷 2789-2795页

作者： Jia-Jun Hu Jia-Qi Liang Zhi-Ping Yan hua-Xiu Ni xiang-Ji Liao You-Xuan Zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou450001China

Efficient multi-resonance thermally activated delayed fluorescence(MR-TADF)materials hold significant potential for applications in organic light-emitting diodes(OLEDs)and ultra-high-definition ***,the stringent synthesis conditions and low yields typically associated with these materials pose substantial challenges for their practical *** this study,we introduce an innovative strategy that involves peripheral modification with sulfur and selenium atoms for two materials,CFDBNS and *** approach enables a directed one-shot borylation process,achieving synthesis yields of 66%and 25%,respectively,while also enhancing reverse intersystem crossing *** emitters exhibit ultra-narrowband sky-blue emissions centered around 474 nm,with full width at half maximum(FWHM)values as narrow as 19 nm in dilute toluene solutions,along with high photoluminescence quantum yields of 98%and 99%in doped films,*** OLEDs based on CFDBNS and CFDBNSe display sky-blue emissions with peaks at 476 and 477 nm and exceptionally slender FWHM values of 23 ***,the devices demonstrate remarkable performances,achieving maximum external quantum efficiencies of 24.1%and 27.2%.This work presents a novel and straightforward approach for the incorporation of heavy atoms,facilitating the rapid construction of efficient MR-TADF materials for OLEDs.

关键词： one-shot synthesis multi-resonance thermally activated delayed fluorescence carbazole-fused dual-boron embedded framework ultra-narrowband emission organic light-emitting diode

Emergence of highly pathogenic avian influenza A(H5N8)clade 2.3.4.4b viruses in grebes in Inner Mongolia and Ningxia,China,in 2021

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Journal of Integrative Agriculture 2024年第1期23卷 348-353页

作者： Qiuzi Xu Xinru Lü Yi Li hua Luo Zhen Zhang xiang Li Rongxiu Qin Qing An Fengyi Qu Zhenliang Zhao Chengbo Zhang Weidong Wang Yuecheng Li Yajun Wang xiangwei Zeng Zhijun Hou Jingqiang Ren Yulong Wang Yanbing Li Hongliang Chai College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040China Harbin Veterinary Research Institute Chinese Academy of Agricultural SciencesHarbin 150040China Wenzhou Key Laboratory for Virology and Immunology Institute of VirologyWenzhou UniversityWenzhou 325000China Ordos Forestry and Grassland Administration Ordos 017000China Monitoring Center for Terrestrial Wildlife Epidemic Diseases Yinchuan 750000China

Highly pathogenic avian influenza(HPAI)subtype H5Nx viruses have spread globally and are a major concern for poultry,wild birds,mammals,and even humans(de Vries et al.2015;Zeng et al.2022).The hemagglutinin(HA)genes of H5 subtype viruses have evolved into multiple clades and some of these clades have been further divided into subclades(Cui et al.2022).Clade 2.***.4.4H5N8 HPAI viruses(HPAIVs)have caused several waves of disease outbreaks in wild birds and domestic poultry(Wang et al.2022).

关键词： poultry Ningxia influenza

The Educational Adaptive-optics Solar Telescope at the Shanghai Astronomy Museum

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Astronomical Techniques and Instruments 2024年第3期1卷 171-178页

作者： Zhimao Du Qing Lin Xuejun rao Yue Zhong Jiawen Yao hua Bao Libo Zhong Yu Liang Hui Zhang Shanghai Astronomy Museum Shanghai 201306China National Laboratory on Adaptive Optics Chengdu 610209China The Laboratory on Adaptive Optics Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

The Educational Adaptive-optics Solar Telescope(EAST)at the Shanghai Astronomy Museum has been running routine astronomical observations since *** is a 65-cm-aperture Gregorian solar telescope for scientific education,outreach,and *** telescope system is designed in an“open”format so that the solar tower architecture can be integrated with it,and visitors can watch the observations live from inside the *** with adaptive optics,a high-resolution imaging system,and an integral field unit spectro-imaging system,this telescope can obtain high-resolution solar images in the TiO and Hαbands,and perform spectral image reconstruction using 400 optical fibers at selected *** can be used not only in public education and scientific outreach but also in solar physics research.

关键词： Astronomy museum Sun observation Adaptive optics Integral field unit

突破“双重劣势”:数字企业国际化创新机制研究——基于最优区分视角

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研究与发展管理 2024年第3期36卷 16-32页

作者：周翔吴冠华孙锐广州大学管理学院广州510006 暨南大学管理学院广州510632

数字企业国际化创新面临来源国劣势和新进劣势共同作用所带来的“双重劣势”挑战,为突破“双重劣势”,数字企业必须拟定有效的国际化创新战略,在“差异化”和“合法性”之间取得平衡。本文以TikTok进军美国市场的成功经验为例,运用最优... 详细信息

数字企业国际化创新面临来源国劣势和新进劣势共同作用所带来的“双重劣势”挑战,为突破“双重劣势”,数字企业必须拟定有效的国际化创新战略,在“差异化”和“合法性”之间取得平衡。本文以TikTok进军美国市场的成功经验为例,运用最优区分理论提炼出了数字企业国际化创新战略演化模型。研究发现:数字企业通过反应式协同平衡数字平台的差异化与合法性进而突破“新进劣势”,借助前瞻式协同平衡数字平台的差异化与合法性进而打破“来源国劣势”,最终占领国际市场。研究结论从最优区分视角为数字企业国际化创新提供了系统的分析框架和管理启示。

关键词：数字企业国际化最优区分新进劣势来源国劣势

Silicone oil migrating into the conjunctival space and orbit after surgery for an eye-penetrating injury:A case report

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World Journal of Clinical Cases 2024年第19期12卷 3950-3955页

作者： Ben-Liang Shu Hong-Yun Wu Yu-xiang Hu Jie rao Bin Wei Qin-Yi huang Xiao-Rong Wu Department of Ophthalmology The First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Ophthalmology Ganzhou People's HospitalGanzhou 341000Jiangxi ProvinceChina

BACKGROUND We report a case of eye-penetrating injury in which a massive silicone oil migration into the patient’s subconjunctival space and orbit occurred after *** SUMMARY A 30-year-old male patient sought medical attention at Ganzhou People’s Hospital after experiencing pain and vision loss in his left eye due to a nail wound on December 9,*** of penetrating injury caused by magnetic foreign body retention in the left eye and hospitalization for *** December 9,2023,pars plana vitrectomy was performed on the left eye for intraocular foreign body removal,abnormal crystal extraction,retinal *** to the discovery of retinal detachment at the posterior pole during surgery,silicone oil was injected to fill the vitreous body,following which upper conjunctival bubble-like swelling was *** orbital computed tomography(CT)review indicated migration of silicone oil to the subconjunctival space and orbit through a self-permeable *** December 18,2023,the patient sought treatment at the First Affiliated Hospital of Nanchang University,*** patient presented with a pronounced foreign body sensation following left eye *** December 20,2023,the foreign body was removed from the left eye frame and an intraocular examination was *** posterior scleral tear had closed,leading to termination of the surgical procedure following supplementary laser treatment around the *** patient reported a significant reduction in ocular surface symptoms just one day after ***,a notable decrease in the migration of silicone oil was observed in orbital CT *** The timing of silicone oil injection for an eye-penetrating injury should be carefully evaluated to avoid the possibility of silicone oil migration.

关键词： Silicone oils Migration Vitrectomy Eye injuries Penetrating Case report