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Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material
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作者 Yuxuan Qi Liang Mao +3 位作者 Chunlan Jiang Guitao Liu Kongxun Zhao Mengchen Zhang 《Defence Technology(防务技术)》 2026年第1期422-435,共14页
This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior... This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique.The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior.The specimens exhibit violent chemical reaction during the fracture process under the impact loading,and the size distribution of their residual debris follows Rosin-Rammler model.The dynamic fracture toughness is obtained by the fitting of debris length scale,approximately 1.87 MPa·m~(1/2).Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression,while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact.Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target,leading to the effective ignition of fuel tank.For the brittleness of as-cast W-ZrTi ESM,further study conducted bond-based peridynamic(BB-PD)C++computational code to simulate its fracture behavior during penetration.The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment.This paper explores a novel as-cast metallic ESM,and provides an available numerical avenue to the simulation of brittle energetic fragment. 展开更多
关键词 Energetic structural material Dynamic fracture behavior Coupled impact effect Mechanical property Peridynamics As-cast W-Zr-Ti alloy
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Pressure and temperature effects resulting from impact onto materials of different reactivity
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作者 Andreas Heine Matthias Wickert 《Defence Technology(防务技术)》 2025年第2期221-230,共10页
The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurrin... The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale setup.This allows deriving qualitative information on the occurring phenomenology as well as quantitative statements about the relative effects sizes as a function of target material and threat.The considered target materials are steel,aluminum,and magnesium.As threats,kinetic energy penetrator,explosively formed projectile,and shaped charge jet are used.For the investigated combinations,the measured overpressures vary by a factor of up to 5 for a variation of the material,by a factor of up to 7 for a variation of the threat,and by a factor larger than 15for a simultaneous variation of both.The obtained results as well as the experimental approach are relevant for the basic understanding of impact effects and risks due to material reactivity.The paper combines two main aims.Firstly,to provide a summary of own prior work in a coherent journal article and,secondly,to review and discuss these earlier results with a new perspective. 展开更多
关键词 impact effects PRESSURE TEMPERATURE Risk assessment Material reactivity
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Effects of manufacturing agglomeration on PM_(2.5) and spatial spillover in prefecture-level cities in China
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作者 Dan Wang Hongxiao Zhao +1 位作者 Yun Wang Yu Cheng 《Chinese Journal of Population,Resources and Environment》 2026年第1期67-76,共10页
Agglomeration supports the high-quality development of the manufacturing industry,and its associated resource and environmental effects play a crucial role in driving green economic development.Based on data from pref... Agglomeration supports the high-quality development of the manufacturing industry,and its associated resource and environmental effects play a crucial role in driving green economic development.Based on data from prefecture-level cities in China from 2005 to 2019,this study employs the inverse distance weighting method,the bivariate local indicator of spatial association model,the spatial Durbin model,and other techniques to explore the relationship between manufacturing agglomeration and PM_(2.5)concentrations,and to assess the impact of its manufacturing agglomeration.Four correlation patterns are observed:high-high,low-low,high-low,and low-high.Among these,high-high and low-low patterns dominate in terms of number of cities.These correlation patterns demonstrate strong temporal stability,with a clear“Matthew effect”.The effect of manufacturing agglomeration on PM_(2.5)levels is significantly negative and helps reduce concentrations regionally,indicating the need to further enhance agglomeration levels regionally.However,it can increase PM_(2.5)levels in neighboring areas due to a siphon effect,and the impact of varies across regions.Compared with levels in 2005-2013,the significance of the relationship between manufacturing agglomeration and PM_(2.5)weakened in the 2013-2019 period.Accordingly,this study proposes countermeasures and policy recommendations aimed at strengthening regional collaborative governance and inspiring differentiated agglomeration strategies to support sustainable economic development in China. 展开更多
关键词 Manufacturing agglomeration PM_(2.5) impact effect Spatial spillover effect
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The Impact of Buzhong Yiqi Decoction Combined with Xuefu Zhuyu Decoction on Cardiac Function and Quality of Life in Patients with Coronary Heart Disease and Heart Failure
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作者 Dein Zhai 《Journal of Clinical and Nursing Research》 2025年第7期346-351,共6页
Objective:To explore the improvement effect of implementing Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction on cardiac function and quality of life of patients during the treatment of coronary heart disease... Objective:To explore the improvement effect of implementing Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction on cardiac function and quality of life of patients during the treatment of coronary heart disease complicated with heart failure.Methods:Eighty cases were included in the study,and they were equally divided into a control group(n=40,treated with basic western medicine)and a study group(n=40,treated with Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction)according to random sampling grouping method.The intervention index results of the two groups were compared.Results:The improvement of cardiac function index,TCM syndrome score,and quality of life in the study group was more prominent,with a statistical value of P<0.05.Conclusion:Buzhong Yiqi Decoction combined with Xuefu Zhuyu Decoction and conventional western medicine treatment can effectively improve the cardiac function of patients with coronary heart disease complicated with heart failure and enhance their quality of life.It is worthy of clinical promotion and application. 展开更多
关键词 Coronary heart disease Heart failure Buzhong Yiqi Decoction Xuefu Zhuyu Decoction impact effect
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Influence of Parenting Care Guidance Combined with Preventive Healthcare on the Effectiveness of Child Family Parenting
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作者 Wei Sun 《Journal of Clinical and Nursing Research》 2025年第8期339-344,共6页
Objective:To explore the impact of parenting care guidance combined with preventive healthcare on child family parenting.Methods:Ninety-two child families were included as research subjects and randomly divided into a... Objective:To explore the impact of parenting care guidance combined with preventive healthcare on child family parenting.Methods:Ninety-two child families were included as research subjects and randomly divided into a control group and an observation group,with 46 cases in each group.The former implemented basic preventive healthcare,while the latter simultaneously carried out parenting care guidance combined with preventive healthcare.The intervention results of the two groups were compared.Results:The observation group had a higher awareness rate of family parenting knowledge and a higher formation rate of healthy behaviors,P<0.05.At the same time,parents’parenting anxiety scores were lower,and family health management ability scores were higher,P<0.05.Moreover,the observation group showed higher scores in children’s social skills,P<0.05.Conclusion:Parenting care guidance combined with preventive healthcare can effectively improve the status of child family parenting,and it is worthy of promotion and application. 展开更多
关键词 Child family parenting Parenting care guidance Preventive healthcare impact effectiveness
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Opportunities to Improve the Quality of Environmental Reports and the Effectiveness of Environmental Impact Assessment: A Case of Electric Power Transmission Systems in Brazil
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作者 Vinícius Arthico Demori Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期124-140,共17页
A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international l... A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international literature has contributed to the understanding of the essential aspects to be verified regarding the quality of EIS, offering a wide spectrum of good practice examples related to the content of the studies. Even so, there is a need for empirical studies that allow the identification of specific aspects related to the context of application of the EIS, which could lead to the identification of opportunities to improve both the quality of the reports and also the effectiveness of EIA. Therefore, the present paper is focused on the quality review of a number of EIS submitted to the Brazilian Federal Environmental Agency (Ibama) to instruct the assessment of electric power transmission systems. Based on the application of the EIS quality review package as proposed by Lee and Colley (1992), the outcomes reveal opportunities for improving the scope of EIA, analysis of alternatives, prediction of magnitude and the assessment of impact significance. Finally, the development and/or adaptation of a similar tool for the systematic review of the quality of EIA reports is recommended. 展开更多
关键词 Environmental impact Assessment effectIVENESS Electric Energy Transmission Systems
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Reformed Environmental Impact Assessment in China: An Evaluation of Its Effectiveness
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作者 Yang Yang 《Journal of Environmental Protection》 2020年第10期889-908,共20页
Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the... Since 2015, a “reform storm” of Environmental Impact Assessment (EIA) opened up in China. This study tries to answer the question of whether these reforms improve the effectiveness of EIA. First, we elaborate on the reforms along with three well-acknowledged components, including EIA legislation, administration, and process. Then, evaluate the reformed EIA system against revised Ahmad and Wood’s criteria. The results demonstrate that the revised laws and regulations are more stringent than the old versions. The EIA process is simplified, and its coordination with the pollutant discharge permit system is promoted. The interim and post-event supervision is currently more robust and the penalties are more severe than before. However, the hierarchical position of the Environmental Protection Law is not high enough and the coordination of different government departments is still challenging. In summary, despite the problems occurring at the initial phase of reforms, the effectiveness of the EIA system has largely been improved. 展开更多
关键词 Environmental impact Assessment REFORM EVALUATION effectIVENESS
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Effects on Sedimentary Processes via Upper Triassic Climate Forcing Caused by Multiple Impacting and Large Igneous Provinces (LIP)-Rifting/Degassing: Jordanian Platform/Arabian Plate and Germanic Basin/Central Europe
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 CAS 2023年第2期136-170,共35页
Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies t... Upper Triassic sedimentary systems of both the Arabian Plate and the Germanic Basin reveal climate- and plate tectonic-forced effects through certain time-intervals experienced by architectural elements, lithofacies types, unconformities, flash flood deposits, maximum flooding surfaces/sequence boundary (MFS/SB), mineralogy, and isotope anomalies. Further, Moon recession and changes of Earth’s rotation velocity (core/mantle boundary) are associated with multiple impacting and large igneous provinces/Mid Oceanic Ridge Basalt, LIP/MORB-rifting/degassing. While acidification (by degassing, sturz-rain) does influence tectosilicates and carbonates, montmorillonite represents a key mineral as transformation of volcanic/impact glass (Tephra) to be found as co-components in and in certain pelite units as “boundary clay-suspicions” (mixture of eolian paleoloess, pelite, paleosol, and tephra → tuffite). Obviously, unconformities and sequence boundaries of both study areas separate and dislocate interrupted ∂<sup>13</sup>C and <sup>87</sup>Sr/<sup>86</sup>Sr-data groups along the isotope curves. Both Proto-Arctic Ocean rifting/degassing comprising kimberlitic pyroclastic eruptions and Neotethys rifting/degassing as well as multiple impacting played the most important role during the Norian, followed by the incipient Central Atlantic Magmatic Provinces rifting since the Rhaetian. The following associations are encountered and dealt with in this study: Sequence boundaries-∂<sup>13</sup>C, maximum flooding surfaces-(FUCs)-∂<sup>13</sup>C, unconformities-plate motion, tephra-pelite-tuffite-montmorillonite. Norian: maximum flooding surfaces (MFSs)-“paleosol”/boundary clay?-rifting-volcanism, Moon/Earth data change. So the Norian (~221 - 206 Ma) hosts anomalous “amalgamated maximum flooding surfaces (MFSs)”, amalgamated paleosol (Jordanian Platform), multiple impacting (~219 - 214 Ma), the maximum opening of the Proto-Arctic Ocean (PAO) (~230 - 200 Ma), Neo-Tethys (NT)-subvolcanic (sills, dikes) in the NE Dead Sea area prior the Rhaetian, and a significant change of Earth/Moon relation data. The study concludes that rare and extreme events are very strongly shaping the geologic constellations in the Earth System. 展开更多
关键词 Endogenic and impact Drivers Sedimentary effects Interplay Processing Event-Stratigraphy
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基于IMPACT有效沟通模型的内部审计沟通关键因素研究
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作者 庄慧超 《鹿城学刊》 2025年第1期69-71,88,共4页
审计沟通在内部审计工作中扮演着举足轻重的角色,对于提升审计质量和水平具有不可忽视的意义。文章首先探讨了审计沟通的重要性,随后引入了IMPACT有效沟通模型的理论框架,并以此为基础进一步分析了内部审计沟通的实施步骤和关键因素。... 审计沟通在内部审计工作中扮演着举足轻重的角色,对于提升审计质量和水平具有不可忽视的意义。文章首先探讨了审计沟通的重要性,随后引入了IMPACT有效沟通模型的理论框架,并以此为基础进一步分析了内部审计沟通的实施步骤和关键因素。通过对沟通模型的运用,旨在提升审计人员的沟通能力,进一步优化内部审计工作的整体效果。 展开更多
关键词 审计沟通 内部审计 impact 有效沟通模型
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城市空间发展对碳排放格局演变的影响效应与减碳路径
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作者 冷红 赵妍 袁青 《规划师》 北大核心 2026年第1期26-34,共9页
厘清城市空间发展如何塑造碳排放格局,对构建有效的规划减碳路径具有关键意义。以哈尔滨为例,基于2007—2021年长时序多源数据,系统追踪建成区空间发展过程与发展模式变化,并构建建成区碳排放空间化模型,将碳排放分析拓展至城市内部精... 厘清城市空间发展如何塑造碳排放格局,对构建有效的规划减碳路径具有关键意义。以哈尔滨为例,基于2007—2021年长时序多源数据,系统追踪建成区空间发展过程与发展模式变化,并构建建成区碳排放空间化模型,将碳排放分析拓展至城市内部精细尺度,刻画碳排放格局的动态演变特征。在此基础上,基于方向—梯度双维度,解析不同空间发展模式对碳排放格局演变的影响效应及形成机理,并针对哈尔滨的碳排放风险区域提出规划减碳路径,为城市碳排放的精细化管控与低碳空间治理提供参考。 展开更多
关键词 城市空间发展 碳排放格局演变 影响效应 夜间灯光
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数字普惠金融对农民增收的影响机制及空间效应研究 被引量:1
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作者 刘桂英 陈跃灵 +1 位作者 谢文君 陈素莹 《农林经济管理学报》 北大核心 2026年第1期100-109,共10页
基于2011—2023年中国省级面板数据,运用固定效应模型、中介效应两步法以及空间杜宾模型,深入探究数字普惠金融对农民增收的影响机制及空间效应。结果表明,数字普惠金融对农民增收具有显著促进作用,数字普惠金融每提高1个单位,农民收入... 基于2011—2023年中国省级面板数据,运用固定效应模型、中介效应两步法以及空间杜宾模型,深入探究数字普惠金融对农民增收的影响机制及空间效应。结果表明,数字普惠金融对农民增收具有显著促进作用,数字普惠金融每提高1个单位,农民收入将提升0.311个单位。影响路径分析表明,数字普惠金融通过支付手段、信贷、农业技术创新和收入分配等途径促进农民增收,其中支付手段效果最明显。空间效应分析表明,本地数字普惠金融的发展对邻近地区农民收入产生负向“虹吸效应”。异质性分析发现,数字普惠金融对农民增收的促进作用存在区域差异,其中对东部地区的影响最为显著。据此,建议持续拓宽数字普惠金融覆盖广度和深度,推动“金融+科技”深度协作,加强区域合作,因地制宜制定数字普惠金融发展措施,共同推动农民增收。 展开更多
关键词 数字普惠金融 农民收入 影响机制 空间效应
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“三线建设”地区工业旅游资源开发对城市高质量发展的影响机制及异质性分析
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作者 唐健雄 周颖 《自然资源学报》 北大核心 2026年第1期228-247,共20页
系统性探索工业旅游资源开发的影响效应,可为实现“三线建设”地区城市高质量发展指明方向。基于空间流动理论,借助熵值法、空间自相关、空间计量模型等方法,探究2011—2022年“三线建设”地区工业旅游资源开发对城市高质量发展的影响... 系统性探索工业旅游资源开发的影响效应,可为实现“三线建设”地区城市高质量发展指明方向。基于空间流动理论,借助熵值法、空间自相关、空间计量模型等方法,探究2011—2022年“三线建设”地区工业旅游资源开发对城市高质量发展的影响机制及异质性。结果表明:(1)“三线建设”地区工业旅游资源开发呈增长态势,但整体开发水平较低;在空间上具有明显的“高行政级别城市驱动”特征。(2)城市高质量发展水平逐年上升,总体绝对差异减小,城市间发展差距拉大,存在“绝对差异缩小相对差异固化”风险;在空间上呈“东南高、西南低”的发展格局。(3)工业旅游资源开发对本地城市高质量发展具有促进作用,但并未显现空间溢出效应;前者对后者各维度的直接效应强度为:创新发展>民生发展>绿色发展>经济发展。(4)工业旅游资源对城市高质量发展具有明显的区域异质性。在直接效应上,西部>中部、北方>南方,而东部地区呈“本地弱效,邻域强溢”的特征。同时,西部、南方地区呈现负向溢出效应。 展开更多
关键词 工业旅游资源开发 城市高质量发展 影响效应 “三线建设”地区
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高填方路堤压实补强现场试验与方案优化
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作者 刘泽 王禹横 +2 位作者 李梦竹 屈畅姿 曹峥 《水利水电科技进展》 北大核心 2026年第1期60-66,82,共8页
以济源-新安高速公路路基工程为依托,设计并开展了高填方黄土路堤压实补强现场试验,探讨了强夯和冲击碾压两种补强方案的加固效果和影响深度,并采用有限元法针对现场补强效果较优的冲击碾压方案开展了施工参数优化分析。结果表明:强夯... 以济源-新安高速公路路基工程为依托,设计并开展了高填方黄土路堤压实补强现场试验,探讨了强夯和冲击碾压两种补强方案的加固效果和影响深度,并采用有限元法针对现场补强效果较优的冲击碾压方案开展了施工参数优化分析。结果表明:强夯补强的影响深度范围为4~6 m,冲击碾压补强的影响深度范围为2~4 m;影响深度范围内土体的加固效果会随夯击次数或碾压遍数的增加而增强,但增幅逐渐减小,存在一个最优的夯击次数或碾压遍数;在现场试验的施工参数条件下,填高2 m后冲击碾压补强比填高4 m后强夯补强更有利于提高路基的压实度及均匀性;冲击碾压补强的影响深度随碾压遍数的增加而增大,碾压遍数达到20遍时其影响深度可达3 m;压实效果和影响深度均随冲击轮质量的增加而增大,随冲击轮行驶速度的增大先增后减,冲击轮最佳行驶速度为3 m/s。 展开更多
关键词 压实补强 高填方 黄土路堤 加固效果 影响深度
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太阳辐射/对流区域边界处的碳、氮、氧元素的电子碰撞电离研究
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作者 侯永 罗青波 +2 位作者 梁欣 曾交龙 袁建民 《物理学报》 北大核心 2026年第1期220-230,共11页
太阳辐射层与对流层边界区域T≈180eV,ne≈9×10^(22)cm^(-3),是太阳内部能量传输方式从辐射主导向对流主导转变的关键界面,也是研究高温稠密等离子体物理的天然实验室.这一区域的物理特性决定了恒星演化模型的可靠性与能量传输机... 太阳辐射层与对流层边界区域T≈180eV,ne≈9×10^(22)cm^(-3),是太阳内部能量传输方式从辐射主导向对流主导转变的关键界面,也是研究高温稠密等离子体物理的天然实验室.这一区域的物理特性决定了恒星演化模型的可靠性与能量传输机制的稳定性,特别是高温稠密等离子体中强烈的碰撞电离会改变电子数密度分布,进而影响能量的输运过程.本文发展了一种耦合等离子体环境效应来计算原子结构的新方法:通过将计算原子结构的Flexible Atomic Code (FAC)与超网链(hypernetted-chain, HNC)近似相结合,在原子波函数计算中引入电子-电子、电子-离子关联函数来考虑等离子体中屏蔽效应,系统研究了极端条件下电子碰撞电离的物理机制.基于扭曲波近似的计算表明,考虑等离子体环境效应时,碳、氮和氧元素的电子碰撞电离截面较自由原子模型显著增强,同时电离阈值出现明显下降的现象.研究发现这种增强效应主要源于离子间强耦合导致的原子势场重叠和自由电子屏蔽引起的束缚态能级移动.本研究直接将离子结构引入电子结构计算的哈密顿量中,所获得的电离参数可直接用于改进太阳内部辐射输运模型,为惯性约束聚变等极端条件等离子体研究提供了理论支持. 展开更多
关键词 辐射/对流区域边界 环境效应 电子碰撞电离 超网链近似
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民族地区铸牢中华民族共同体意识教育的影响效应与对策建议——基于广西5147名青少年学生的实证研究
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作者 黄健毅 张海波 《青海民族大学学报(社会科学版)》 2026年第1期157-166,共10页
教育是铸牢中华民族共同体意识的主要路径,在青少年学生中华民族共同体意识培育中起着关键的作用。然而,当前铸牢中华民族共同体意识教育的研究主要集中在理论论证方面,基于实证数据剖析铸牢中华民族共同体意识教育效应的研究相对匮乏... 教育是铸牢中华民族共同体意识的主要路径,在青少年学生中华民族共同体意识培育中起着关键的作用。然而,当前铸牢中华民族共同体意识教育的研究主要集中在理论论证方面,基于实证数据剖析铸牢中华民族共同体意识教育效应的研究相对匮乏。对广西壮族自治区5147名青少年学生进行调查,以了解民族地区学校、家庭、社区三个空间场域的铸牢中华民族共同体意识教育对青少年学生中华民族共同体意识的影响效应,结果发现,民族地区铸牢中华民族共同体意识教育对青少年学生中华民族共同体意识有着重要的影响效应。其中,学校教育的总体影响效应最强,其次是家庭教育,最后是社区教育,但在对中华文化的认同等维度中家庭教育也起着不可替代的作用。民族地区青少年学生中华民族共同体意识教育的总体状况良好,但尚存在学校铸牢中华民族共同体意识教育各学段之间衔接不佳、家庭和社区的铸牢中华民族共同体意识教育相对薄弱等问题。加强中华民族共同体意识教育,需要有形有感有效开展铸牢中华民族共同体意识教育、全学段一体化开展铸牢中华民族共同体意识教育、家校社政协同开展铸牢中华民族共同体意识教育。 展开更多
关键词 民族地区 中华民族共同体意识 影响效应 青少年学生
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中等冲击动载下蠕变煤体加速失稳破坏试验研究
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作者 王俊 胡亚波 +2 位作者 宁建国 党延龙 张朝辉 《岩土力学》 北大核心 2026年第3期816-827,838,共13页
深部煤岩体蠕变特征明显,在中等冲击动载(冲击能量等级介于10^(3)~10^(4) J)作用下,蠕变煤岩体会发生时滞型失稳破坏,这给工程灾害的评估与预警带来了一定的困难。针对这一问题,利用自行研制的蠕变-冲击试验系统,开展了中等冲击动载下... 深部煤岩体蠕变特征明显,在中等冲击动载(冲击能量等级介于10^(3)~10^(4) J)作用下,蠕变煤岩体会发生时滞型失稳破坏,这给工程灾害的评估与预警带来了一定的困难。针对这一问题,利用自行研制的蠕变-冲击试验系统,开展了中等冲击动载下蠕变煤体力学响应特征研究,分析了中等冲击动载对煤体蠕变破坏的影响,讨论了中等冲击动载加速蠕变煤体破坏的机制。试验结果表明:(1)提高中等冲击动载强度与次数,可促使煤体由等速蠕变变形提前进入加速蠕变变形阶段,同时降低煤体进入加速蠕变阶段的时间与应力阈值;(2)在低应力水平下蠕变煤体仅具有硬化效应,但中等冲击动载下煤体呈现出硬化-损伤效应,最终诱发煤体产生以张拉破裂为主导的宏观破坏模式;(3)提出了蠕变煤体“冲击损伤应力”概念,即当应力水平最低为0.4σ_(c)时中等冲击动载加速蠕变煤体损伤破坏,此应力状态可认为是蠕变煤体的“抗冲击损伤强度”。研究结果可为深部矿井冲击地压灾害预警与防控提供一定的理论支撑。 展开更多
关键词 蠕变 冲击动载 加速失稳 硬化效应 损伤效应
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重力和粘结性能对RC梁冲击位移及尺度效应的影响分析
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作者 李健 张仁波 +2 位作者 金浏 兰冬璆 杜修力 《振动工程学报》 北大核心 2026年第2期454-463,共10页
受试验成本与条件限制,根据缩尺试验结果和经典相似律预测原型足尺梁的响应已成为一种常用手段。为研究冲击荷载下经典相似律的适用性,开展了落锤冲击下RC梁跨中位移响应尺度效应的数值分析。建立了考虑重力和钢筋-混凝土粘结滑移关系... 受试验成本与条件限制,根据缩尺试验结果和经典相似律预测原型足尺梁的响应已成为一种常用手段。为研究冲击荷载下经典相似律的适用性,开展了落锤冲击下RC梁跨中位移响应尺度效应的数值分析。建立了考虑重力和钢筋-混凝土粘结滑移关系的RC梁有限元模型,对比了几何相似RC梁的归一化跨中位移时程与峰值,讨论了塑性、重力和粘结性能对RC梁跨中峰值位移及其尺度效应的影响。结果表明:低速冲击下,RC梁跨中峰值位移不满足经典相似律,随着结构尺寸的增大,归一化跨中峰值和残余位移逐渐增大;弹性梁与弹塑性梁和RC梁的冲击位移尺度效应规律不一致,塑性和损伤均为冲击位移产生尺度效应的原因之一;考虑重力和粘结滑移单一或共同作用后,RC梁跨中峰值位移增大,尺度效应增强;建议在开展大尺寸或原型RC梁低速冲击数值研究时考虑重力和粘结滑移作用,以保证跨中峰值位移结果的准确性,进而提高应用峰值位移进行评估或预测的可靠性。 展开更多
关键词 结构工程 低速冲击 数值分析 钢筋混凝土梁 尺度效应
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数字经济如何重塑产业链韧性——绿色与智能化协同发展的链式传导机制
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作者 邹筱 张金薇 于英杰 《商学研究》 2026年第1期106-117,共12页
提升产业链韧性是我国建设现代化产业体系的关键。本文基于2011—2022年我国省域面板数据,构建产业链韧性和数字经济评价指标体系,实证检验数字经济对产业链韧性的影响及作用机制。研究发现,数字经济能够显著提升产业链韧性;机制分析发... 提升产业链韧性是我国建设现代化产业体系的关键。本文基于2011—2022年我国省域面板数据,构建产业链韧性和数字经济评价指标体系,实证检验数字经济对产业链韧性的影响及作用机制。研究发现,数字经济能够显著提升产业链韧性;机制分析发现,数字经济发展通过促进产业链绿色发展和提高产业链智能化水平推动产业链韧性提升;异质性分析发现,中部地区和产业集聚水平低的地区数字经济的产业链韧性提升效应更明显。为充分发挥数字经济在提升产业链韧性中的作用,政府应持续投资并优化数字基础设施建设,鼓励企业采用先进的数字技术,针对不同地区实施差异化发展策略。企业应充分利用绿色数字技术,建立智能供应链管理系统,加大数字经济人才培养力度。 展开更多
关键词 数字经济 产业链韧性 影响研究 中介效应
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现代景观遗产累积性影响评估研究——以兴庆宫公园提升项目为例
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作者 王新文 魏萌 杨芮琪 《古建园林技术》 2026年第1期44-49,共6页
城市更新的时代背景下,尚未列入各级文物保护单位的现代景观类遗产在提升改造工程中,其核心价值易受损害。基于现代景观遗产的物质性及其在历史演进中社会属性,构建了基于累积性的遗产影响评估框架与“本体—环境—社会”三维指标体系,... 城市更新的时代背景下,尚未列入各级文物保护单位的现代景观类遗产在提升改造工程中,其核心价值易受损害。基于现代景观遗产的物质性及其在历史演进中社会属性,构建了基于累积性的遗产影响评估框架与“本体—环境—社会”三维指标体系,结合遗产价值认知与载体识别提出了遗产价值影响减缓措施,并以西安兴庆宫公园提升项目为案例开展了实证研究,指出了幕景分析法在累积性遗产影响评估中的适用性及公众与专家在遗产影响评估中关注点的异同。 展开更多
关键词 现代景观遗产 遗产影响评估 累积性影响 兴庆宫公园
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Dynamic responses of cable-stayed bridges to vehicular loading including the effects of the local vibration of cables 被引量:7
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作者 He ZHANG Xu XIE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第8期593-604,共12页
Stay cables, the primary load carrying components of cable-stayed bridges (CSBs), are characterised by high flexi-bility which increases with the span of the bridge. This makes stay cables vulnerable to local vibratio... Stay cables, the primary load carrying components of cable-stayed bridges (CSBs), are characterised by high flexi-bility which increases with the span of the bridge. This makes stay cables vulnerable to local vibrations which may have significant effects on the dynamic responses of long-span CSBs. Hence, it is essential to account for these effects in the assessment of the dynamics CSBs. In this paper, the dynamic responses of CSBs under vehicular loads are studied using the finite element method (FEM), while the local vibration of stay cables is analyzed using the substructure method. A case study of a cable-stayed steel bridge with a center span of 448 m demonstrates that stay cables undergo large displacements in the primary mode of the whole bridge although, in general, a cable’s local vibrations are not obvious. The road surface roughness has significant effects on the interaction force between the deck and vehicle but little effect on the global response of the bridge. Load impact factors of the main girder and tower are small, and the impact factors of the tension of cables are larger than those of the displacements of girders and towers. 展开更多
关键词 Cable-stayed bridge(CSB) Vehicular load Local vibration of cable impact effect
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