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Chinese Physics b 2024年第1期33卷 134-142页

作者：张华平范蓓蓓吴佳琦李茂枝 Department of Physics Beijing Key Laboratory of Opto-electronic Functional Materials&Micro-nano DevicesRenmin University of ChinaBeijing 100872China Songshan Lake Materials Laboratory Dongguan 523808China Key Laboratory of quantum State Construction and Manipulation Renmin University of ChinaBeijing 100872China

The dramatic temperature-dependence of liquids dynamics has attracted considerable scientific interests and efforts in the past decades, but the physics of which remains elusive. In addition to temperature, some other parameters, such as pressure, loading and size, can also tune the liquid dynamics and induce glass transition, which makes the situation more complicated. Here, we performed molecular dynamics simulations for Ni_(50)Zr_(50) bulk liquid and nanodroplet to study the dynamics evolution in the complex multivariate phase space, especially along the isotherm with the change of pressure or droplet size. It is found that the short-time Debye–Waller factor universally determines the long-time relaxation dynamics no matter how the temperature, pressure or size changes. The basic correlation even holds at the local atomic scale. This finding provides general understanding of the microscopic mechanism of dynamic arrest and dynamic heterogeneity.

关键词： metallic glass-forming liquids structure relaxation dynamical heterogeneity Debye–Waller factor

Magnetic/Magnetostrictive Properties Together with Resistivity and Corrosion behaviors of CoFe_2 and Its Composite with CoFe_2N

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Journal of Materials Science & Technology 2017年第7期33卷 744-750页

作者： b.q.Geng Y.q.Ma M.Wang Z.L.Ding W.H.Song b.C.Zhao Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

The CoFe_2alloy（CF） was prepared by reducing CoFe_2O_4 in the H_2 ambient. Subsequently the CF sample was nitrided in the NH_3 atmosphere to produce the composite of CoFe_2N and CoFe_2. The magnetostriction, thermal expansion, resistivity and corrosion resistance of CF sample and the nitrided sample（CFN）at 1000？C were investigated. The saturation magnetostriction coefficiency λ_s and thermal expansion coefficient ？ at 300 K for the nitrided CFN were 50 ppm and 10 ppm/K, respectively, approximately equal to those for the CF sample. However, compared with CF, CFN presents a decrease in temperature coefficient R_λ（300 K） of magnetostriction by 11%. The smaller resistivity and improved corrosion resistance in the H_2SO_4 solution may expand the applications of the CoFe_2 in the fields needing lower resistivity or in the acidic environment.

关键词： CoFe alloy CoFe_2N alloy Magnetostriction Resistivity Corrosion resistance

An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy q.Tang Min-Rui Du Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-Li Xiao Peng-bin Han Jian-Ran Wen Shi-qian Yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina botanic Institute of barcelona(Ibb CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

Efficacy evaluation of zirconia crown on primary molars with caries defects

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Hua Xi Kou qiang Yi Xue Za Zhi / West China Journal of Stomatology 2024年第5期42卷 652-659页

作者： Deng S. Niu S. Gao q. Zhang L. Chen Z. Liu M. Dept. of Stomatology Shenzhen Children’ s Hospital Shenzhen 518026 China Dept. of Stomatology The People’ s Hospital of Longhua Shenzhen 518109 China Dept. of Maxillofacial Surgery Shenzhen Second People’ s Hospital Shenzhen 518029 China

Objective This study aimed to estimate the therapeutic effects of preformed metal crown (PMC) and prefabricated zirconia crowns (ZC) on decayed primary morals in children, as well as to analyze the possible influencing factors. Methods A retrospective cohort study was performed on the data of 192 patients (aged 3 to 8) in the Stomatological Department of Shenzhen Children’s Hospital from October 2021 to December 2021. The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and ZC, including 96 cases (96 caries) in the PMC group and 96 cases (96 caries) in the ZC group. Oral clinical examination was performed at 3 months, 1 year, and 2 years after treatment, overwiewing the clinical therapeutic effects and periodontal status of PMC and ZC groups, as well as recording the crown integrity, gingival index (GI), probing bleeding index (bI), plaque index (PLI) and various prosthetic indices. Results No significance differences existed in the periodontal status of PMC and ZC groups at 3 months, 1 year, and 2 years after treatment (P>0.05). However, the GI, bI, and PLI in the PMC group were higher than those in the ZC group at 3 months, 1 year, and 2 years after treatment, and the difference was dramatically significant (P0.05), as well as in the GI, bI, and PLI, between the two groups (P>0.05). No significant differences existed in various prosthetic indices between genders after PMC restoration (P>0.05). The scores of girls in various prosthetic indices after ZC restoration were higher than those of boys (Pbetween age in the PMC group and the GI, bI, PLI, and FDI indices (P0.05). Conclusion PMC and ZC can be applied to restore deciduous molar caries. The periodontal status of deciduous teeth in ZC group was superior to that in the PMC group. The

关键词： gingival index plaque index prefabricated zirconia crowns preformed metal crown probing bleeding index

同舟共济:艺术乡建中的多主体联动机制与在地实践

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公共艺术 2024年第1期 16-26页

作者：渠岩(文/图) 广州美术学院城乡艺术建设研究院

乡村建设如星火燎原之势,持续在广大乡村蔓延和拓展,这种自上而下的运动持续之长和波及之广让全社会始料未及。其中,最普遍的形式要数政府主导的“美丽乡村”整治计划和资本开发的“乡村旅游”景点打造,这种单一权力意志与资本开发主导... 详细信息

乡村建设如星火燎原之势,持续在广大乡村蔓延和拓展,这种自上而下的运动持续之长和波及之广让全社会始料未及。其中,最普遍的形式要数政府主导的“美丽乡村”整治计划和资本开发的“乡村旅游”景点打造,这种单一权力意志与资本开发主导下的乡村建设对乡村造成了极大的改变。由于中国乡村历史悠久、分布地域广阔,存在许多特殊的复杂性和偶然的多变性。乡村建设作为如此复杂的系统工程,任何单一主体都无法独立完成。如果说介入理念和方法至关重要,那运作机制更不可忽视。因为运作机制会直接影响乡建理念的有效落地。所以,总结和建构出一种有利于乡村建设行之有效的介入机制,才能保证在乡村建设过程中少走弯路,这也是最佳的“乡建之道”。

关键词：艺术介入乡村实践路径运作机制多主体联动

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太阳能热水系统节能率与设计参数的探讨

给水排水 2024年第3期50卷 109-113页

作者：敖凯湖南省建筑设计院集团股份有限公司长沙410012

太阳能热水系统的能耗主要为辅热系统的能耗,其节能率与系统设计保证率呈正相关。通过分析太阳辐照量与生活热水耗热量的关系可知,选取节能率变化曲线偏离点处的太阳能保证率可避免出现热量浪费和一次投资过大,保证较高的经济效益。选... 详细信息

太阳能热水系统的能耗主要为辅热系统的能耗,其节能率与系统设计保证率呈正相关。通过分析太阳辐照量与生活热水耗热量的关系可知,选取节能率变化曲线偏离点处的太阳能保证率可避免出现热量浪费和一次投资过大,保证较高的经济效益。选取了长沙地区的3种典型的设置集中热水供应系统的建筑进行分析,依据长沙地区的气象参数和此三类建筑生活热水耗热量的变化特征,得出各自节能率变化曲线偏离点处的太阳能保证率的取值。同时,根据公式计算了长沙地区平板型太阳能集热器的年平均集热效率;推导了q_(rid)值的计算方法并推荐了在长沙地区的取值。

关键词：太阳能热水系统节能率太阳辐照量生活热水耗热量集热效率太阳能保证率

SUbCONVERGENCE OF FINITE ELEMENTS AND A SELF-ADAPTIVE ALGORITHM

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Journal of Computational Mathematics 1996年第4期14卷 336-344页

作者： Zhu q D Lin q 南京大学数力系江苏南京中科院系统科学所北京

An analysis of the chaotic motion of particles of different sizes in a gas fluidized bed

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Particuology 2008年第6期6卷 549-556页

作者： Y.q. Feng A.b. Yu Lab for Simulation and Modelling of Particulate Systems School of Materials Science and Engineering University of New South Wales Sydney NSW 2052 Australia

The dynamic behavior of individual particles during the mixing/segregation process of particle mixtures in a gas fluidized bed is analyzed. The analysis is based on the results generated from discrete particle simulation, with the focus on the trajectory of and forces acting on individual particles. Typical particles are selected representing three kinds of particle motion： a flotsam particle which is initially at the bottom part of the bed and finally fluidized at the top part of the bed; a jetsam particle which is initially at the top part of the bed and finally stays in the bottom de-fluidized layer of the bed; and a jetsam particle which is intermittently joining the top fluidized and bottom de-fluidized layers. The results show that the motion of a particle is chaotic at macroscopic or global scale, but can be well explained at a microscopic scale in terms of its interaction forces and contact conditions with other particles, particle-fluid interaction force, and local flow structure. They also highlight the need for establishing a suitable method to link the information generated and modeled at different time and length scales.

关键词： Fluidization Segregation Discrete particle simulation Granular dynamics

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癫痫持续状态死亡法医学鉴定1例

法医学杂志 2024年第1期40卷 83-85页

作者：靳茜茜白雅琴陈念念董祎铭高学慧孙修强王君丽曹洁梁新华郭相杰山西医科大学法医学院山西晋中030600 平遥县公安局刑事侦查大队技术中队山西晋中031100

1案例1.1简要案情赵某,女,33岁,某日晚与宋某入住宾馆。期间二人发生性关系。00:00,赵某反复出现四肢抽搐、口吐白沫及气喘症状,宋某认为其可自行恢复,故在其发作期间未采取任何救助措施。赵某在症状发作间歇期持续昏迷,于当日17:00死... 详细信息

1案例1.1简要案情赵某,女,33岁,某日晚与宋某入住宾馆。期间二人发生性关系。00:00,赵某反复出现四肢抽搐、口吐白沫及气喘症状,宋某认为其可自行恢复,故在其发作期间未采取任何救助措施。赵某在症状发作间歇期持续昏迷,于当日17:00死亡。经查赵某生前无颅脑外伤史,有癫痫病史5年余,规律服用抗癫痫药物(奥拉西坦片、左乙拉西坦片、奥卡西平片),死亡前2 d自行停用抗癫痫药物。

关键词：法医病理学癫痫持续状态死亡原因

应用钆布醇的稳态MR血管成像评估股骨头缺血性坏死病人的血供变化

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国际医学放射学杂志 2024年第1期 129-130页

作者： Z.H.Liao C.Liu b.Wu C.Ma b.Ming q.Zhou 陈莉

摘要目的探讨应用钆布醇行稳态（SS）MR血管成像（MRA）评价股骨头坏死（ONFH）血供变化的可行性。方法前瞻性纳入2021年12月—2022年5月招募的参与者。比较

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