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Convergence for Imaginary Time Step evolution in the Fermi and Dirac seas

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Science China(Physics,Mechanics & Astronomy) 2010年第2期53卷 327-330页

作者： LI FangQiong1,ZHANG Ying2 & MENG Jie2,3.4 1Guizhou university for Nationalities,Guiyang 550025,China 2State Key Lab Nucl. Phys. & Tech.,School of Physics,Peking university,Beijing 100871,China 3.chool of Physics and Nuclear Energy Engineering,Beihang university,Beijing 100191,China 4D{3. of Physics,university of stellenbosch,stellenbosch,south africa 1. Guizhou university for Nationalities Guiyang 550025 China2. State Key Lab Nucl. Phys. & Tech. School of Physics Peking University Beijing 100871 China3. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China4. Department of Physics University of Stellenbosch Stellenbosch South Africa

The convergence for the Imaginary Time Step (ITS) evolution with time step is investigated by performing the ITS evolution for the Schrdinger-like equation and the charge-conjugate Schrdinger-like equation deduced from Dirac equation for the single proton levels of 12C in both the Fermi and Dirac seas. For the guaranteed convergence of the ITS evolution to the "exact" results,the time step should be smaller than a "critical" time step Δtc for a given single-particle level. The "critical" time step Δtc is more sensitive to the quantum numbers |κ| than to the energy of the single-particle level. For the single-particle levels with the same κ,their "critical" time steps are in the same order. For the single-particle levels with similar energy,a relatively small (large) "critical" time step for larger (smaller) |κ| is needed. These conclusions can be used in the future self-consistent calculation to optimize the evolution procedure.

关键词： Dirac equation Schrdinger-like equation Imaginary Time Step method convergence

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新一轮家电“以旧换新”行动方案影响

日用电器 2024年第3期 1-2页

作者： 1.华创证券 2.光大证券 3.中信期货华创证券光大证券中信期货

国务院印发《推动大规模设备更新和消费品以旧换新行动方案》（以下简称《行动方案》），明确了5方面20项重点任务和实施设备更新、消费品以旧换新、回收循环利用、标准提升四大行动，提出积极开展家电等消费品以旧换新。《行动方案》...

国务院印发《推动大规模设备更新和消费品以旧换新行动方案》（以下简称《行动方案》），明确了5方面20项重点任务和实施设备更新、消费品以旧换新、回收循环利用、标准提升四大行动，提出积极开展家电等消费品以旧换新。《行动方案》家电直接相关内容1.到2027年废旧家电回收量较2023.增长3.%,

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Optimization of the imaginary time step evolution for the Dirac equation

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Science China(Physics,Mechanics & Astronomy) 2011年第2期54卷 231-235页

作者： LI FangQiong1,ZHANG Ying2,LIANG HaoZhao2,3.& MENG Jie4,2,5 1Guizhou university for Nationalities,Guiyang 550025,China 2State Key Lab Nuclear Physics & Technology,School of Physics,Peking university,Beijing 100871,China 3.nstitut de Physique Nucle’aire,IN2P3.CNRS and Universite’ Paris-Sud,F-91406 Orsay Cedex,France 4School of Physics and Nuclear Energy Engineering,Beihang university,Beijing 100191,China 5D{3. of Physics,university of stellenbosch,stellenbosch,south africa 1. Guizhou university for Nationalities Guiyang 550025 China2. State Key Lab Nuclear Physics & Technology School of Physics Peking University Beijing 100871 China3. Institut de Physique Nucléaire IN2P3-CNRS and Université Paris-Sud F-91406 Orsay Cedex France4. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China5. Department of Physics University of Stellenbosch Stellenbosch South Africa

Taking the single neutron levels of 12C in the Fermi sea as examples,the optimization of the imaginary time step(ITS) evolution with the box size and mesh size for the Dirac equation is *** the weakly bound states,in order to reproduce the exact single-particle energies and wave functions,a relatively large box size is *** long as the exact results can be reproduced,the ITS evolution with a smaller box size converges faster,while for both the weakly and deeply bound states,the ITS evolutions are less sensitive to the mesh ***,one can find a parabola relationship between the mesh size and the corresponding critical time step,i.e.,the largest time step to guarantee the convergence,which suggests that the ITS evolution with a larger mesh size allows larger critical time step,and thus can converge faster to the exact *** conclusions are very helpful for optimizing the evolution procedure in the future self-consistent calculations.

关键词： Dirac equation Schrdinger-like equation imaginary time step method convergence

Selected issues at the interface between nuclear physics and astrophysics as well as the standard model

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中国科学：物理学、力学、天文学英文版 2011年第S1期54卷 119-123页

作者： MENG Jie1,2,3. NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2,4 1State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking university, Beijing 100871, China 2School of Physics and Nuclear Energy Engineering, Beihang university, Beijing 100191, China 3.epartment of Physics,{3., stellenbosch, south africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 3.3.2, Germany 1. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China 2. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China 3. Department of Physics University of Stellenbosch Stellenbosch South Africa 4. Justus-Liebig-Universit?t Giessen Heinrich-Buff-Ring 14 Giessen 35392 Germany

The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in Beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.

关键词： rapid neutron-capture process nuclear chronometer isospin symmetry-breaking corrections

HL-3.置欧姆等离子体中高频磁流体不稳定性的实验观测

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核聚变与等离子体物理 2024年第3期44卷 328-333页

作者：杨秋磊陈伟张洁程时葵梁绍勇张轶泼 HL-3.验团队核工业西南物理研究院成都610041

在HL-3.置1MA电流等离子体欧姆放电实验期间,米尔诺夫(Mirnov)探针测量到两种高频磁流体(MHD)不稳定性。在等离子体启动阶段,电流爬升受到抑制,碘化钠探测器测量到逃逸电子增加。同时Mirnov探针测量到多分支频率f为20~400k Hz的高频MH... 详细信息

在HL-3.置1MA电流等离子体欧姆放电实验期间,米尔诺夫(Mirnov)探针测量到两种高频磁流体(MHD)不稳定性。在等离子体启动阶段,电流爬升受到抑制,碘化钠探测器测量到逃逸电子增加。同时Mirnov探针测量到多分支频率f为20~400k Hz的高频MHD不稳定性。结果表明,这种不稳定性的出现与逃逸电子增加密切相关,并抑制了等离子体电流的爬升,损失了大约7%伏秒数。等离子体电流和密度爬升时,Mirnov探针测量到频率f为110~160k Hz的高频MHD不稳定性。这种不稳定性频率与芯部阿尔芬频率成正比,处于环向阿尔芬本征模频率范围。随着这种不稳定性的演化,等离子体发生了破裂。这些高频MHD不稳定性的研究对于HL-3.续放电及未来ITER的初始放电有重要的参考意义。

关键词：等离子体磁流体不稳定性逃逸电子破裂

复方碘口腔喷雾原位膜的制备及促口腔溃疡修复评价

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中国药科大学学报 2024年

作者：张小军黄山芩郭潇涵季梦菲沈雁陈大全许颖 1.江苏大学药学院 2.中国药科大学药学院 3.烟台大学药学院江苏大学药学院中国药科大学药学院烟台大学药学院

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对... 详细信息

采用原位凝胶技术，制备了新型复方碘口腔喷雾原位膜，用于发挥缓释作用，并促进口腔溃疡创面修复。首先以喷雾状态和成膜时间为指标，对喷雾药液的处方和工艺进行优化。以成膜时间和药膜黏附性为评价指标对药液混合比例进行考察。并对最优处方制备的复方碘口腔喷雾药液的药物含量、稳定性、pH、喷雾效果，及原位膜的成膜时间、溶解性、吸湿性、保湿性、体外释放等理化性质进行考察；此外，通过细胞实验考察了成膜材料的生物相容性及复方碘口腔喷雾原位膜的促迁移效果；采用兔口腔溃疡模型，对复方碘口腔喷雾在体成膜效果及促修复效果进行评价。实验结果显示，最优处方制备的药液A和药液B的pH分别为6.21 ± 0.02和 6.42 ± 0.03.符合正常口腔黏膜pH范围；稳定性好，具有良好的喷雾状态；药液B中碘含量为（1.96 ± 0.01）mg/mL；原位膜体外成膜时间为（118.3.± 3.6）s，口腔内成膜时间为（13..3.± 4.6）s；24 h溶解率为（87.3. ± 1.74）%，吸湿率为（124.17 ± 7.13.%，保湿率为（26.85 ± 2.50）%；复方碘口腔喷雾原位膜中碘含量为（47.42 ± 0.3.）mg/g；具有良好的柔韧性和黏附性，并具有一定的缓释效果。细胞实验中，原位膜表现出良好的促成纤维细胞迁移作用。兔口腔溃疡实验表明，复方碘口腔喷雾在体可快速成膜，并可显著促进口腔溃疡修复。本研究所开发的复方碘口腔喷雾原位膜，制备工艺稳定，并可有效促进口腔溃疡创面修复，为口腔黏膜制剂的研究和开发提供了新思路，并具有良好的转化前景。

关键词：口腔喷雾原位膜复方碘口腔溃疡缓释促修复

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science China(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. Department of Chemistry, Qingdao university, Qingdao 266071, China 2. Department of Chemistry, Tsinghua university, Beijing 100084, China 3. Department of Physics, Qingdao university, Qingdao 266071, China 1. Department of Chemistry Qingdao University Qingdao 266071 China 2. Department of Chemistry Tsinghua University Beijing 100084 China 3. Department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Micromorphology of Surface Crusts in the Knersvlakte,south africa

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Journal of Mountain Science 2009年第2期6卷 189-196页

作者： Sarah-Jane C.Fox Anthony J.Mills Rosa M.Poch Department of Soil Science Stellenbosch UniversityStellenbosch South Africa Department of Environment and Soil Science University of LleidaRovira Roure 191 Lleida

Soils in the Knersvlakte are particularly prone to crusting and have lower inherent infiltrability than other soils across western southern africa. Micromorphological techniques were used to examine the structure and porosity of soil crusts in the Knersvlakte to ascertain why crusting is so intense in this region. Quantile regression using boundary lines was employed to examine the relationships between infiltrability and soil properties for all samples （n = 67）. This analysis showed that infiltrability is potentially maximal at low water- dispersible ＇clay plus silt＇ content and low silt content （r^2 = 0.72 and 0.64; respectively, n = 67）（Figure 2）. The strength of crusts, pH, EC, clay mineralogy, and water-dispersible clay, silt and ＇clay plus silt＇ content were compared, and a pore analysis using optical microscopy was undertaken on images of six soil thin sections （n = 6）（circular and parallel polarizers）. Pore analysis was further undertaken on five horizontal slices of equal dimensions taken through each soil thin section. The porosity samples with low infiltrability （〈 100 mm·hr^-1, n = 4） had greater crust strength, lower porosity （both total and in the least porous slice） and greater water-dispersible ＇day plus silt＇ and silt content than the porosity samples with high infiltrability （〉 100mm·hr^-1, n = 2）. The porosity samples with low infiltrability showed a trend of lower pH and greater water dispersible clay percentage. Porosity varied within the porosity samples due to the presence of dense clay/silt bands （〈 0.5 mm in width） with relatively few air vesicles. The porosity samples with horizontal slices of low porosity （but large numbers of air vesicles） had low infiltrability, while those without slices of low porosity （and relatively few air vesicles） had high infiltrability. We conclude that the intense crusting and resultant low infiltrability of soils in the Knersvlakte appears to be related to the formation of thin, dense clay/silt bands in the

关键词： Infiltrability optical microscopy porosity air vesicles

社会化批注能否提升阅读理解水平？基于个体化和社会化批注对比的实验研究

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中国图书馆学报 2024年

作者：李武艾鹏亚姚琦 1.上海交通大学媒体与传播学院 2.南洋理工大学黄金辉传播与信息学院 3.华东师范大学心理与认知科学学院上海交通大学媒体与传播学院南洋理工大学黄金辉传播与信息学院华东师范大学心理与认知科学学院

社会化批注是用户开展社会化阅读的重要实践活动。借鉴计算机支持的协作学习框架和认知负荷理论，本研究采用实验法比较个体化和社会化批注对读者文本阅读理解水平的影响。实验结果显示，虽然社会化批注并未显著影响自我评估的阅读理解... 详细信息

社会化批注是用户开展社会化阅读的重要实践活动。借鉴计算机支持的协作学习框架和认知负荷理论，本研究采用实验法比较个体化和社会化批注对读者文本阅读理解水平的影响。实验结果显示，虽然社会化批注并未显著影响自我评估的阅读理解水平，但对专家打分的阅读理解水平产生了显著的正向影响。中介分析进一步表明，相对于个体化批注，社会化批注提高了读者的感知阅读支持，后者又提升了自我评估和专家打分的阅读理解水平；与个体化批注相比，社会化批注对读者的感知阅读干扰没有显著影响，而感知阅读干扰对通过两种测量方式获取的阅读理解水平也都没有显著的预测作用。理论层面，本研究有助于更加深入全面地洞察社会化批注对阅读理解水平的影响及其背后的作用机理。实践层面，研究结果对社会化阅读软件（尤其对其批注功能）的设计和完善具有重要的参考作用，也能启发阅读推广者思考如何引导读者利用社会化批注的积极作用提升对文本内容的理解和掌握。表5。参考文献52。

关键词：社会化阅读社会化批注个体化批注阅读理解计算机支持的协作学习框架认知负荷理论