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Journal of Rare Earths 2024年第1期42卷 36-45,I0002页

作者： Xiaoli Luo Qichen Chen Hongbo Guo Heng Zhang Xiaowei He wu zhao School of Mathematics and Computer Science Ningxia Normal UniversityGuyuan756099China School of Information Science and Technology Northwest UniversityXi'an710127China

Fluorescence imaging techniques represent essential tools in in vitro,preclinical,and clinical *** this study,an improved one-step hydrothermal method to synthesize citric acid(CA)modifiedα-NaYbF_(4):2%Er^(3+)nanocrystals was *** introduction of various doping ions into NaYbF_(4):2%Er^(3+)and the different valence states of the same ions affect both the crystal size and upconversion luminesce *** fore,we investigated the upconversion luminesce nce enha ncement of NaYbF_(4):2%Er^(3+)by ion doping and find that the upconversion luminescence intensity of the upconversion nanoparticles(UCNPs)co-doped with 5 mol%Fe^(2+)ions shows the greatest enhancement,especially for red emission at654 ***,HeLa cells incubated with UCNPs allow for imaging with strong red upconversion emission detectio *** laser scanning microscope(CLSM)fluorescent images of HeLa cells indicate that NaYbF_(4):2%Er/5%Fe^(2+)leads to a clear outline and improves visualization of the cell *** addition,the CA coated NaYbF_(4):2%Er^(3+)/5%Fe^(2+)nanoparticles and NaYbF_(4):2%Er^(3+)/5%Fe^(2+)show low cytotoxicity in HeLa *** imaging reveals the efficiency of these UCNPs to analyze the lungs,liver,and ***,these results indicate that the Cit-NaYbF_(4):2%Er^(3+)/5%Fe^(2+)UCNPs are efficient nanoprobes for fluorescence molecular to mography.

关键词： Hydrothermal method Fe^(2+)ion doping Tuning size Nanoprobes Fluorescence imaging Rare earths

Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

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Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： Zhi-Kang Chen wu-Chao zhao Yi-Ling zhao Cong-Lei Liu Liu-Yin Jiang Yue-Tao Zhang Hong-Ping Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been *** P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were *** the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy *** pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)*** thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

Experimental research on the launching system of auxiliary charge with filter cartridge structure

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Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun Chen Ze He Hong-Hao Ma Lu-Qing Wang zhao-wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the *** combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the *** breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the *** this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the *** proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the *** order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are *** experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak *** projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,*** muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the *** the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

A Novel Two-dimensional Low-redundancy Array Design for Solar Radio Imaging

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Research in Astronomy and Astrophysics 2024年第9期24卷 178-189页

作者： Weidan Zhang Bing Wang zhao wu Guang Lu Yao Chen Yan Fabao Laboratory for Electromagnetic Detection Institute of Space SciencesShandong UniversityWeihai 264209China Center for Integrated Research on Space Science Astronomyand PhysicsInstitute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China

The radioheliograph is an extensive array of antennas operating on the principle of aperture synthesis to produce images of the *** image acquired by the telescope results from convoluting the Sun’s true brightness distribution with the antenna array’s directional *** imaging quality of the radioheliograph is affected by a multitude of factors,with the performance of the“dirty beam”being simply one *** factors such as imaging methods,calibration techniques,clean algorithms,and more also play a significant influence on the resulting image *** the layout of the antenna array directly affects the performance of the dirty beam,the design of an appropriate antenna configuration is critical to improving the imaging quality of the *** on the actual needs of observing the Sun,this work optimized the antenna array design and proposed a twodimensional low-redundancy *** proposed array was compared with common T-shaped arrays,Y-shaped arrays,uniformly spaced circular arrays,and three-arm spiral *** simulations and experiments,their performance in terms of sampling point numbers,UV coverage area,beam-half width,sidelobe level,and performance in the absence of antennas are compared and *** was found that each of these arrays has its advantages,but the two-dimensional low-redundancy array proposed in this paper performs best in overall *** has the shortest imaging calculation time among the array types and is highly robust when antennas are missing,making it the most suitable choice.

关键词： interferometers methods:observational techniques:interferometric

An improved non-uniform fast Fourier transform method for radio imaging of coronal mass ejections

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Astronomical Techniques and Instruments 2024年第2期1卷 117-127页

作者： Weidan Zhang Bing Wang zhao wu Shuwang Chang Yao Chen Fabao Yan Laboratory for Electromagnetic Detection Institute of Space SciencesShandong UniversityWeihaiWeihai 264209China Center for Integrated Research on Space Science Astronomyand PhysicsInstitute of Frontier and Interdisciplinary ScienceShandong UniversityQingdaoQingdao 266237China School of Mechanical Electrical&Information EngineeringShandong UniversityWeihaiWeihai 264209China

Radioheliographs can obtain solar images at high temporal and spatial resolution,with a high dynamic *** are among the most important instruments for studying solar radio bursts,understanding solar eruption events,and conducting space weather *** study aims to explore the effective use of radioheliographs for solar observations,specifically for imaging coronal mass ejections(CME),to track their evolution and provide space weather *** have developed an imaging simulation program based on the principle of aperture synthesis imaging,covering the entire data processing flow from antenna configuration to dirty map *** grid processing,we propose an improved non-uniform fast Fourier transform(NUFFT)method to provide superior image *** simulated imaging of radio coronal mass ejections,we provide practical recommendations for the performance of *** study provides important support for the validation and calibration of radioheliograph data processing,and is expected to profoundly enhance our understanding of solar activities.

关键词： Radio interference Gridding Imaging Non-uniform fast Fourier transform

20世纪四五十年代的新歌剧与英雄叙事——以歌剧《刘胡兰》版本为例

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四川戏剧 2024年第6期 72-76页

作者：武兆晋中学院中文系天津师范大学文学院

根据刘胡兰事迹创作的歌剧是英雄刘胡兰叙事的重要传播媒介。歌剧《刘胡兰》目前共有五个版本,通过梳理歌剧《刘胡兰》最初创作的背景以及版本变迁的过程,揭示了歌剧《刘胡兰》的经典化建构,不仅符合延安文艺座谈会召开以来塑造英雄人... 详细信息

根据刘胡兰事迹创作的歌剧是英雄刘胡兰叙事的重要传播媒介。歌剧《刘胡兰》目前共有五个版本,通过梳理歌剧《刘胡兰》最初创作的背景以及版本变迁的过程,揭示了歌剧《刘胡兰》的经典化建构,不仅符合延安文艺座谈会召开以来塑造英雄人物的主流基调,而且对借助新歌剧表现理想的现代英雄作了有益探索,对刘胡兰形象的传播发挥了关键的作用。

关键词：歌剧《刘胡兰》英雄叙事版本变迁经典化建构

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WTO的性质及其改革:基于规制经济学视角

上海对外经贸大学学报 2024年第4期31卷 55-68页

作者：吴朝阳吴婵江西财经大学国际经贸学院南昌330013 南昌工程学院经济贸易学院南昌330013

WTO多边贸易体制必须尽快改革已成国际社会共识。从国内外各界所提改革方案看,普遍缺乏科学的理论支撑以对WTO是什么、应具何种使命、应该做什么、应当怎么做等基本命题进行系统的规范性解释。本文从规制经济学视角审视WTO的性质及其改... 详细信息

WTO多边贸易体制必须尽快改革已成国际社会共识。从国内外各界所提改革方案看,普遍缺乏科学的理论支撑以对WTO是什么、应具何种使命、应该做什么、应当怎么做等基本命题进行系统的规范性解释。本文从规制经济学视角审视WTO的性质及其改革,认为WTO应定性为致力于治理贸易领域国际市场失灵的多边规制组织,其存在的具体问题包括规制目标越位缺位、规制架构设计不合理、规制机制未与时俱进、规制能力建设不足以及规制供给滞后。具体改革建议包括对WTO的目标使命进行重新审视,对WTO的治理架构进行再造,多措并举提升WTO规制效能,加强边境内规制和社会性规制以及加强WTO规制能力建设。从改革策略看,建议借鉴乌拉圭回合经验,将WTO改革问题纳入多哈回合一体推进。从长远看,各方还应考虑将WTO升级为世界贸易与投资组织的必要性与可能性。

关键词： WTO改革国际市场失灵规制经济学

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港澳回归对区域经济民生发展的影响

亚太经济 2024年第2期 118-128页

作者：吴肇光俞如涛福建社会科学院福州350001 福建社会科学院中国式现代化研究中心福州350001 澳门科技大学商学院中国澳门999078

港澳回归以来,“一国两制”方针为祖国经济长期平稳、快速发展作出了重大贡献。基于港澳回归的准自然实验框架,探讨港澳回归对粤港澳区域经济民生发展的影响。实证研究表明,港澳回归对该区域综合经济民生指数和人均GDP增长率存在积极的... 详细信息

港澳回归以来,“一国两制”方针为祖国经济长期平稳、快速发展作出了重大贡献。基于港澳回归的准自然实验框架,探讨港澳回归对粤港澳区域经济民生发展的影响。实证研究表明,港澳回归对该区域综合经济民生指数和人均GDP增长率存在积极的影响与正外部性;港澳回归后,区域内各城市通过互联互通与资源禀赋的优化配置使经济民生加速发展,对区域内各城市影响的异质性主要与其距离和产业结构有关。

关键词：港澳回归区域发展经济民生

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BTA深孔加工镗杆的横向随机振动

振动与冲击 2024年第3期43卷 46-57页

作者：赵武张全斌李亚敏荆双喜河南理工大学机械与动力工程学院河南焦作454003 新乡学院机电工程学院河南新乡453003

采用随机方法分析了蕴含轴向流动流体的BTA(boring and trepanning association)深孔镗杆在随机力下的横向随机动力行为。建模时考察了流固耦合镗杆承受的弯曲、拉伸和扭转变形;经Galerkin Method离散化处理,分析了BTA镗杆在有、无随机... 详细信息

采用随机方法分析了蕴含轴向流动流体的BTA(boring and trepanning association)深孔镗杆在随机力下的横向随机动力行为。建模时考察了流固耦合镗杆承受的弯曲、拉伸和扭转变形;经Galerkin Method离散化处理,分析了BTA镗杆在有、无随机激励两种情况的特征值和特征频率对振动特性的影响;利用响应方差最大值和谱密度解析了BTA镗杆横向振动的临界转速与临界失稳频率;明确了镗杆随转速、刚度、初始轴向总力和剪切模量等参数变化对系统振动特性的影响机制:镗杆转速变化对系统稳定性不再具有单调性,随BTA镗杆转速持续增加,系统可历经两次转速的临界失稳,相继出现二次失稳和二次稳定;增加系统等效刚度和等效剪切模量会促进工作过程的稳定,改变轴向力对工作过程稳定的影响不明显;并以随机振动物理试验信号的功率谱分析,验证了理论仿真结果与试验结果的一致性。该研究在一定程度上揭示了BTA深孔工艺系统运动状态的复杂性,这种研究模式为进一步分析在复杂状态下的运动演化提供了更多的可能。研究结论为更好地理解BTA深孔镗杆工作时的随机动力行为提供了依据,也为BTA深孔工艺过程的振动控制和参数优化奠定了理论基础。

关键词： BTA深孔镗杆横向振动随机振动特性特征值响应方差谱密度

正断层阶区现今连接模式综合研究——以山西裂谷系口泉断裂禅房阶区为例

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地震地质 2024年第4期46卷 837-855页

作者：花春雨苏鹏石峰席茜郭钊吾中国地震局地质研究所地震动力学国家重点实验室北京100029 山西太原大陆裂谷动力学国家野外科学研究站太原030025

正断层阶区有软连接(soft-link)和硬连接(hard-link)2种端元连接模式。判定正断层阶区现今的连接模式不但有助于理解正断层的生长演化过程,也能指示未来正断层上发生的地震是否会在阶区内形成地表破裂,这对于评价阶区内工程场地的地震... 详细信息

正断层阶区有软连接(soft-link)和硬连接(hard-link)2种端元连接模式。判定正断层阶区现今的连接模式不但有助于理解正断层的生长演化过程,也能指示未来正断层上发生的地震是否会在阶区内形成地表破裂,这对于评价阶区内工程场地的地震安全性具有重要意义。判定正断层阶区内是否存在活动的连接断层是区别正断层阶区现今连接模式的直接方法。然而,在多数情况下,由于正断层阶区内的变形量相对小,加上人类活动对阶区内地貌的改造,导致在本以硬连接模式生长的正断层阶区内也很难直接看到断层陡坎,这为判定正断层阶区内是否存在活动的连接断层带来了困难。山西裂谷系是东亚大陆显著的活动裂谷带,也是中国重要的强震带。口泉断裂位于山西裂谷系北部,是大同盆地的西缘边界断裂。口泉断裂在禅房村附近发育一个正断层阶区,文中称之为禅房阶区。文中以口泉断裂禅房阶区为例,通过构造地貌野外调查、地貌数据分析和地质雷达探测研究禅房阶区的连接模式。结果显示,口泉断裂禅房阶区内部存在活动的连接断层,说明禅房阶区的连接方式为硬连接模式。文中研究基于构造地貌野外调查、地貌数据分析和地质雷达探测的综合方法,可有效定位弱活动断层的空间展布,降低单一方法的不确定性。

关键词：正断层阶区连接方式口泉断裂山西裂谷系

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