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Associations between Mental Health Outcomes and Adverse Childhood Experiences and Character Strengths among University Students in Southern China 被引量:2
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作者 Yulan Yu Rassamee Chotipanvithayakul +2 位作者 Hujiao Kuang Wit Wichaidit Chonghua Wan 《International Journal of Mental Health Promotion》 2023年第12期1343-1351,共9页
Adverse childhood experiences(ACEs)can negatively affect mental health,whereas character strengths seem to be positively correlated with mental health.Detailed information on the history of ACEs among university stude... Adverse childhood experiences(ACEs)can negatively affect mental health,whereas character strengths seem to be positively correlated with mental health.Detailed information on the history of ACEs among university students in China and the extent which mental health is associated with ACEs and character strengths can contribute to the needed empirical evidence for relevant stakeholders.Objectives of this study are 1)to estimate the prevalence of ACEs among undergraduate students in Southern China;and 2)to assess the extent which mental health outcomes(positive growth,well-being,and depression)are associated with ACEs and character strengths among undergraduate students in Southern China.We conducted a self-administered survey amongfirst and second-year students at a university in Southern China and analyzed data using descriptive statistics and linear regression analyses.Among the 779 students who completed the questionnaire,283 were males,439 were females,and 57 did not indicate their gender.The prevalence of ACEs among the participants was 32.1%.History of ACEs was associated with lower positive growth score(Adjusted Beta=-0.20;95%CI=-0.37,-0.02;p=0.030)and lower well-being score(Adjusted Beta=-1.13;95%CI=-2.04,-0.23;p=0.014).Vitality domain of character strength was associated with all three mental health outcomes after adjusting for covariables(all p-values<0.001).Our studyfindings provide empirical evidence for stakeholders in university mental health.However,caveats regarding lack of temporality,selection bias,social desirability bias,and lack of generalizability should be considered in the interpretation of the studyfindings. 展开更多
关键词 Adverse childhood experience character strength positive growth WELL-BEING depressive symptoms
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Determinants of Positive Mental Health in Adolescents–A Cross-Sectional Study on Relationships between Positive Mental Health, Self-Esteem, Character Strengths and Social Inclusion 被引量:1
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作者 Hanna Ahrnberg Kaija Appelqvist-Schmidlechner +2 位作者 Pekka Mustonen Sari Fröjd Katja Aktan-Collan 《International Journal of Mental Health Promotion》 2021年第3期361-374,共14页
Adolescence is a crucial time period with especial vulnerability for development of mental health problems.Growing interest is focusing on the determinants of positive mental health in order to find the key concepts t... Adolescence is a crucial time period with especial vulnerability for development of mental health problems.Growing interest is focusing on the determinants of positive mental health in order to find the key concepts that could be influenced in the promotion of mental well-being of adolescents.In this study we aim to explore the relations between self-esteem,character strengths and experience of social inclusion as determinants of adolescents’positive mental health controlled for selected sociodemographic background factors.The study population(n=195)consisted of comprehensive school students who filled in an electronic questionnaire of adolescent’s mental well-being in Fall 2019.The questionnaire included measures of Warwick-Edinburgh Mental Well-being Scale(WEMWBS),VIA Youth-measure 96,Rosenberg Self-Esteem Scale and Experience of Social Inclusion Scale.The methods included group comparisons and General Linear Model computed by SPSS 24.0.The strongest association was found between positive mental health and self-esteem(β=0.789,p<0.001),followed by character strengths of hope and kindness and experience of social inclusion.Interestingly,family’s socioeconomic factors did not associate significantly with positive mental health in the final statistical model.In terms of our results,it seems that self-esteem,character strengths and experience of social inclusion might have stronger association with adolescents’mental well-being than family’s socioeconomic determinants.Therefore,it should be discussed whether psychological determinants overcome the individual effect of poor socioeconomic status as factors that influence positive mental health.Further studies are needed to establish these results more firmly. 展开更多
关键词 Positive mental health mental well-being character strengths SELF-ESTEEM social inclusion ADOLESCENCE
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The mediating role of strengths use between character strengths and mental health in Chinese high school students 被引量:1
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作者 SUN Wenmei 《International English Education Research》 2017年第6期105-107,共3页
The present study aimed to examine the mediating effect of strengths use between character strengths and mental health in high school students. Totally 508 China high school students completed questionnaires measuring... The present study aimed to examine the mediating effect of strengths use between character strengths and mental health in high school students. Totally 508 China high school students completed questionnaires measuring character strengths, strengths use and mental health for middle school students' inventory. The correlations between character strength, strengths use and mental health were all significantly positive, 0.41 -0.65, P 〈 0.01. Character strengths significantly positively predicted mental health, and standard regression coefficient was 0.65, P 〈 0.01. Strengths use mediated partially the relationship between character strengths and mental health in high school students and the value of mediating effect was 11.3%. Strengths use played a moderated mediating role in the relationship between character strengths and mental health. 展开更多
关键词 character strengths strengths use Mental health High school students
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Progress in the evaluation tool of Character Strengths and its application in nursing staff
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作者 Ming-Hui Ning Gui-Hong Yan 《Nursing Communications》 2024年第16期1-6,共6页
Character Strengths is a group of positive personality traits reflected through cognition,behavior,and emotion,which play a positive role in improving happiness,alleviating negative emotions,and maintaining physical a... Character Strengths is a group of positive personality traits reflected through cognition,behavior,and emotion,which play a positive role in improving happiness,alleviating negative emotions,and maintaining physical and mental health.This article reviews the concept,content,methods,evaluation tools,and application progress of Character Strengths in nurses,so as to provide a reference for clinical managers and improve the quality of life,mental health,and professional satisfaction of n urses. 展开更多
关键词 character strengths nurses REVIEW
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Texture,Grain Boundary Characterization and Segregation of Phosphorus in an Annealed Interstitial Free Steel 被引量:1
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作者 Xin-li SONG Kun PENG +3 位作者 Ze-xi YUAN Juan JIA Jing LIU Li-xia FAN 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2014年第9期844-848,共5页
The {111} fiND plane texture, grain boundary characterization and grain boundary segregation of phos- phorus are investigated for the phosphorus added high strength interstitial free (IF) steel annealed at 810℃ for... The {111} fiND plane texture, grain boundary characterization and grain boundary segregation of phos- phorus are investigated for the phosphorus added high strength interstitial free (IF) steel annealed at 810℃ for 60 s to 180 s. The results show that the maximum volume fraction of {111} fiND plane texture is about 85% and the grain boundary Segregation peak of phosphorus is about 14 at. % for the steel annealed at 810℃ for 120 s. The ∑3 and other low-∑CSL (coincident site lattice) boundaries are lowest for the steel annealed for 120 s. Segregation of phosphorus is also found at low angle grain boundaries. 展开更多
关键词 high strength IF steel texturel grain boundary characterization SEGREGATION
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Resistance of Cement Paste and Its Relationship to Strength under the Corrosive Action of Ambient Media
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作者 Weilun Wang Shiqun Li +1 位作者 Jiashan Hu Feng Xing 《Engineering(科研)》 2012年第6期291-296,共6页
In this study, we measured the resistances (test frequency 837.8 Hz) of the paste of Portland cement (PC) and phosphoaluminate cement (PALC) subjected to different types of corrosion and different numbers of freeze-th... In this study, we measured the resistances (test frequency 837.8 Hz) of the paste of Portland cement (PC) and phosphoaluminate cement (PALC) subjected to different types of corrosion and different numbers of freeze-thaw cycles. This study aimed to improve understanding of the changing characteristics of paste resistance from both micro and macro perspectives by associating changes in the paste microstructure with changes in the paste mechanical strength using X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and other methods. Our results showed that changes in the paste resistance under the corrosive action of ambient media could signal the deterioration of paste structure and loss of paste strength. Continuous hydration reactions within the paste were found to render it more dense and increase its resistance. Invasion of corrosive ions was found to continue to increase paste resistance if the structure of the cement paste was not destroyed. Otherwise, paste resistance would decrease. Corrosive media were found to cause the dispersion of hydrated gels with certain degree of polymerization. Because spatial resistance was found to cause difficulty in the transportation of ion clusters, the decreases in resistance caused by long-term corrosion might be reduced due to a compensation effect. This effect was found to be related to the severity of structural damage to the paste. The magnitudes of corrosive effects of chemical media on the radicals in the cement paste structure were found to occur in the following order: SiO4 > AlO4 > PO4. The resistance and strength of the PC was always lower than those of PALC. In addition, losses of resistance and strength by PALC were mainly due to deterioration of the radical structure of AlO6. 展开更多
关键词 CEMENT PASTE AMBIENT Media RESISTANCE characterization Microstructure strength
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Characterization of the copper-containing amine oxidase from Trifolium pratense seedlings
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作者 Yong-Ming Zhang Guo-Long Li +2 位作者 Rui-Bo ZhongYu-Xing Ma Pei Gong Feng Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第3期138-144,共7页
We studied the kinetic characterizations of the Trifolium pratense seedlings copper-containing amine oxidase(TPAO) by using various amine-containing substrates.The catalyzing rate for all of amine-containing substrate... We studied the kinetic characterizations of the Trifolium pratense seedlings copper-containing amine oxidase(TPAO) by using various amine-containing substrates.The catalyzing rate for all of amine-containing substrates can be ordered as diamines > polyamines > aromatic monoamines,and it shows an apparent trend in each category of substrates such as the longer the carbon chain,the lower the V_(max) is,so does the V_(max)/K_m values but is opposite for the K_m value of TPAO.The distinct differences between the kinetic parameters for different amine-containing substrates indicated that the rate-determining step of the catalytic reaction strongly depends on the substrate's chemical structure.It is concluded that both pH and ionic strength can affect the catalytic activity of TPAO via influencing the coulomb interaction-mediated enzyme-substrate docking processes,which can be attributed to the potential of charged groups from both substrates and the activity sites of TPAO by the regulation of ionic strength. 展开更多
关键词 胺氧化酶 含铜 幼苗 红三叶 表征 库仑相互作用 催化速率 离子强度
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Interfacial characterization of resistance spot welded joint of steel and aluminum alloy 被引量:3
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作者 张伟华 孙大千 +3 位作者 殷世强 韩立军 邱小明 陈庆雷 《China Welding》 EI CAS 2010年第4期6-10,共5页
The dissimilar material resistance spot welding of galvanized high strength steel and aluminum alloy had been conducted. The welded joint exhibited a thin reaction layer composed of Fe2Al5 and Fe4Al13 phases at steel/... The dissimilar material resistance spot welding of galvanized high strength steel and aluminum alloy had been conducted. The welded joint exhibited a thin reaction layer composed of Fe2Al5 and Fe4Al13 phases at steel/aluminum interface. The welded joint presented a tensile shear load of 3.3 kN with an aluminum alloy nugget diameter of 5.7 mm. The interfacial failure mode was observed for the tensile shear specimen and fracture occurred at reaction layer and aluminum alloy fusion zone beside the interface. The reaction layer with compounds was the main reason for reduction of the welded joint mechanical property. 展开更多
关键词 high strength steel aluminum alloy resistance spot welded joint interfacial characterization
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非等压下考虑损伤劣化的巷道稳定性
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作者 经来旺 吕将 +2 位作者 郑睿 崔子琦 经纬 《科学技术与工程》 北大核心 2025年第25期10619-10627,共9页
为了研究不均匀地应力环境下的圆形巷道损伤后的稳定性问题,将巷道围岩的应力场和考虑损伤效应的统一强度理论进行了关联分析,推导了非等压条件下的巷道围岩塑性区半径、位移及应力分布的解析解。通过具体算例,分析了侧压力系数、中间... 为了研究不均匀地应力环境下的圆形巷道损伤后的稳定性问题,将巷道围岩的应力场和考虑损伤效应的统一强度理论进行了关联分析,推导了非等压条件下的巷道围岩塑性区半径、位移及应力分布的解析解。通过具体算例,分析了侧压力系数、中间主应力、方位角及损伤特性对围岩变形的综合影响。研究结果表明:侧压力系数对巷道围岩塑性区的形状与尺寸具有显著影响,并且在不同方位角下,塑性区半径随侧压力系数的变化呈现不同的规律性特征,在工程实践中,可依据该规律针对性地指导巷道支护的形式与时机;随着中间主应力的增大,巷道围岩塑性区的半径和位移均呈现出减小的趋势;随着围岩损伤程度的加剧,塑性区的半径及位移均明显增大。 展开更多
关键词 圆形巷道 损伤特性 统一强度理论 侧压力系数 中间主应力
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基于随钻数据的岩体强度预测模型及其适配性评价
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作者 赵志强 王箫鹤 武璟 《煤炭学报》 北大核心 2025年第10期4743-4758,共16页
为了研究在锚杆钻机钻进过程中实时识别顶板岩层强度及结构状态,为巷道掘进过程中进行顶板隐患探测提供技术途径,采用综合研究手段,揭示了不同强度岩体及组合岩体的钻进信号响应规律,研究了基于钻进数据的岩体强度表征及预测模型,并对... 为了研究在锚杆钻机钻进过程中实时识别顶板岩层强度及结构状态,为巷道掘进过程中进行顶板隐患探测提供技术途径,采用综合研究手段,揭示了不同强度岩体及组合岩体的钻进信号响应规律,研究了基于钻进数据的岩体强度表征及预测模型,并对比评估了其适配性。结果表明:推力、扭矩及转速等信号对围岩强度的变化具有较强的响应性,与岩层结构变化呈现一致性,三轴振动对岩体强度的响应性较不明显,但在岩层界面处信号突变显著;各表征参量及其强度表征值趋势与钻进信号趋势基本保持一致,基于钻头单位体积研磨能的单轴抗压强度表征模型与真实值偏离度最小(适配性最优);推力及扭矩与除三轴振动之外的其他参量均呈现较为明显的线性正相关关系,转速也同样具有较为明显的线性相关关系,但与除可钻性指数外其他特征均呈负相关趋势,三轴振动中,X方向与Y方向振动与其余各特征相关性程度较小,但仍存在一定相关性,其中Z方向振动中相关性程度极小。Attention-CNN模型在鲁棒性、准确率和适配性上表现最优,预测值与由单轴压缩实验所得的真实值之间决定系数R^(2)达0.94,拟合度最高,在岩体单轴抗压强度预测上预测精度较其他模型的模型精度至少超出12%,研究成果为巷道顶板岩层强度实时感知及支护决策提供了理论与技术支撑。 展开更多
关键词 巷道顶板 随钻探测 岩层识别 回归预测模型 强度表征模型
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异种金属复合结构连接强度的超声厚度共振表征方法研究
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作者 霍磊 袁玲 +2 位作者 孙凯华 沈中华 何华彬 《应用声学》 北大核心 2025年第5期1179-1191,共13页
异种金属复合结构是航空航天与军工领域的重要应用组件,实现其复合界面连接强度的无损表征具有重要意义。该文研究了关于超声Lamb波的厚度共振对异种金属双层复合板中界面连接强度的表征方法。通过引入法向和切向的弹簧模型来模拟双层... 异种金属复合结构是航空航天与军工领域的重要应用组件,实现其复合界面连接强度的无损表征具有重要意义。该文研究了关于超声Lamb波的厚度共振对异种金属双层复合板中界面连接强度的表征方法。通过引入法向和切向的弹簧模型来模拟双层金属板之间的连接,推导了异种金属双层复合板中Lamb波的厚度共振频率与界面连接强度之间的定量关系。发现对于铝-非铝双层金属板,厚度共振频率会随界面连接强度的降低而单调递减,并且S_(1)模态和A_(1)模态为界面连接强度表征的最佳模态。两层板的厚度比和材料性质的变化,会分别对厚度共振频率随界面连接强度的敏感变化区间和频率变化总值产生影响。使用了频域模拟的方法,对铝-非铝双层金属板中不同界面连接强度下的厚度共振频率进行计算,其结果与理论值相吻合,验证了理论结果的准确性。 展开更多
关键词 异种金属复合结构 LAMB波 厚度共振 强度表征
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热暴露时效对DD6合金组织和强度的影响
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作者 崔文明 张晓辰 +4 位作者 王巍 李铸铁 王纪兴 张瑞 梁锡炳 《稀有金属材料与工程》 北大核心 2025年第8期2071-2078,共8页
对DD6镍基单晶高温合金进行热暴露时效处理获得不同程度的退化组织,研究组织退化演变机理以及对应剩余强度和断裂机理,并探讨组织退化损伤程度的参量表征方式,建立组织退化损伤程度与剩余强度间的量化映射关系。结果表明,在热暴露时效... 对DD6镍基单晶高温合金进行热暴露时效处理获得不同程度的退化组织,研究组织退化演变机理以及对应剩余强度和断裂机理,并探讨组织退化损伤程度的参量表征方式,建立组织退化损伤程度与剩余强度间的量化映射关系。结果表明,在热暴露时效过程中,γ′相按照Ostwald熟化机制回溶或长大,980℃下1190 h和1100℃下100 h后γ′相含量已基本达到热力平衡态,γ相和γ′相随着温度升高和时间延长继续粗化并趋于稳定,最终γ相宽度约400 nm和γ'相宽度约760 nm。在粗化的同时,DD6合金在内部γ/γ′相错配应力或外加应力作用下,组织发生筏化。粗化和筏化均降低了合金的强度。综合考虑粗化和筏化作用,本研究采用微观结构尺寸参量ωλ^(2)与剩余强度建立了良好的量化映射关系式,且该损伤量化表征方式不受合金初始态微观结构尺寸的约束。 展开更多
关键词 DD6合金 热暴露时效 组织退化 剩余强度 量化表征
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定向钢纤维增强地聚物强度性能试验及模型表征
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作者 周华飞 江汶鸿 +1 位作者 施开轩 谢子令 《复合材料学报》 北大核心 2025年第11期6528-6542,共15页
为研究定向钢纤维增强地聚物复合材料(Aligned steel fiber reinforced geopolymer composites,ASFRGPC)的强度性能,设计了不同地聚物配合比和钢纤维长径比的ASFRGPC试件及相应的素地聚物试件,进行了立方体抗压、棱柱体轴心抗压、立方... 为研究定向钢纤维增强地聚物复合材料(Aligned steel fiber reinforced geopolymer composites,ASFRGPC)的强度性能,设计了不同地聚物配合比和钢纤维长径比的ASFRGPC试件及相应的素地聚物试件,进行了立方体抗压、棱柱体轴心抗压、立方体劈裂抗拉及棱柱体弯拉试验,探讨了受力破坏机制及强度变化规律,分析了强度间的相互关系,建立了强度表征模型。结果表明:配合比和原材料成分的差异并不显著影响素地聚物强度间的相互关系。棱柱体抗压强度与立方体抗压强度近似符合线性关系,且两者之间的比例系数与文献报道的比例系数接近;劈裂抗拉强度或弯拉强度与棱柱体抗压强度基本符合幂函数关系,澳大利亚《地聚物和碱激发混凝土结构设计规程》的推荐模型可直接用于表征它们的关系,预测值的平均绝对误差不超过12%。定向钢纤维显著改善了抗拉及抗弯性能,ASFRGPC的劈裂抗拉强度和弯拉强度相较于素地聚物分别提高了120%和100%以上,而随机分布钢纤维对劈裂抗拉强度和弯拉强度的增强往往不超过50%和80%。同时,定向钢纤维也影响抗压强度,提高垂直于轴向荷载方向的抗压强度,而降低平行于轴向荷载方向的抗压强度。ASFRGPC的强度模型可由素地聚物的强度模型结合纤维特征值的线性函数建立,劈裂抗拉强度、弯拉强度和弹性模量模型均取得了优异的预测性能,预测值的平均绝对误差均不大于5%。 展开更多
关键词 地聚物 定向钢纤维 抗压强度 劈裂抗拉强度 弯曲强度 模型表征
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基于修正Cowper-Symonds模型的高强度低合金钢HC340LAD+Z高应变速率性能和表征模型
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作者 曹宏利 《锻压技术》 北大核心 2025年第9期286-296,共11页
针对高强度低合金钢HC340LAD+Z,研究了其微观组织、化学成分和静态力学特性,开展了7种应变速率下的力学性能测试,并分析了不同应变速率下的试样断口形貌和高应变速率的裂纹分布。基于修正Cowper-Symonds模型,对不同应变速率下的力学性... 针对高强度低合金钢HC340LAD+Z,研究了其微观组织、化学成分和静态力学特性,开展了7种应变速率下的力学性能测试,并分析了不同应变速率下的试样断口形貌和高应变速率的裂纹分布。基于修正Cowper-Symonds模型,对不同应变速率下的力学性能曲线进行拟合,并与试验结果和Johnson-Cook模型拟合结果进行对比。最终采用三点弯曲冲击试验验证了所搭建材料模型的可靠性。结果表明:材料呈现明显的应变速率敏感性,不同应变速率下的断口均呈韧窝状,裂纹最先萌生在晶界处,距离断口表面越近,裂纹密度越大;修正Cowper-Symonds模型的拟合度更高,有效应力偏差最大值为1.29%;三点弯曲冲击试验与仿真分析的载荷-位移曲线高度一致,修正Cowper-Symonds模型最大载荷和最大载荷时位移的偏差均比Johnson-Cook模型更小,分别为2.04%和1.30%。说明修正Cowper-Symonds模型对HC340LAD+Z合金高应变速率性能的表征精度较高。 展开更多
关键词 高强度低合金钢 应变速率 表征模型 断口形貌 裂纹 本构模型
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光波辅助焊接工艺及其焊接效果研究
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作者 黄程超 王相朝 +1 位作者 彭洪波 许仁初 《灯与照明》 2025年第3期186-188,共3页
针对传统焊接工艺存在的热影响区宽泛、残余应力集中等问题,本文通过建立光波能量场与材料相变行为的耦合模型,揭示了光频调制对熔池动力学特征和界面结合机制的调控规律,并构建了涵盖光波参数、热源分布与机械约束条件的多维度工艺控... 针对传统焊接工艺存在的热影响区宽泛、残余应力集中等问题,本文通过建立光波能量场与材料相变行为的耦合模型,揭示了光频调制对熔池动力学特征和界面结合机制的调控规律,并构建了涵盖光波参数、热源分布与机械约束条件的多维度工艺控制体系。采用多尺度表征方法,研究发现光波辅助焊接在微观尺度能形成梯度过渡的冶金结合层;宏观力学测试表明,其接头疲劳寿命较常规工艺提升约2.3倍。此外,本文提出了工艺稳定性控制策略,开发了实时光谱监测的闭环反馈系统,将焊接缺陷率有效控制在0.5%以下。该技术在航空航天精密构件连接中展现出优异的工程适用性,其局部能量聚焦特性为异种材料焊接提供了创新解决方案。 展开更多
关键词 光波辅助焊接 连接强度 工艺可靠性 多尺度表征 冶金结合层
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结构性损伤膨胀土三轴加载下的裂隙形态及力学表征 被引量:8
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作者 程明书 汪时机 +2 位作者 毛新 陈正汉 江胜华 《岩土工程学报》 EI CAS CSCD 北大核心 2016年第S2期73-78,共6页
基于Kachanov连续损伤变量及Fredlund非饱和土有效应力理论,提出了结构性损伤膨胀土的强度表征方法。以南水北调中线工程南阳膨胀土为研究对象,利用改进型非饱和土三轴仪对不同损伤程度的三组15个重塑试样进行控制净围压分别为50,100,15... 基于Kachanov连续损伤变量及Fredlund非饱和土有效应力理论,提出了结构性损伤膨胀土的强度表征方法。以南水北调中线工程南阳膨胀土为研究对象,利用改进型非饱和土三轴仪对不同损伤程度的三组15个重塑试样进行控制净围压分别为50,100,150 k Pa的三轴压缩试验,定量分析荷载作用下初始孔洞损伤基元及裂隙演化形式对膨胀土力学特性的影响。实验表明:考虑结构性及损伤的非饱和土力学表征能够很好地描述土体的力学行为;孔洞损伤对膨胀土强度没有一致的强化或弱化效果,而裂隙发育形态、演化形式对土体结构及强度起主导作用;围压能够一定程度上抑制裂隙的开展,通过裂隙面咬合产生强度。根据破坏机制将该力学关系表示为裂隙发育及残余强度两个阶段,线性硬化破坏、弹塑性破坏、脆塑性破坏、线性软化破坏四种破坏模式。研究可为揭示膨胀土边坡破坏的力学机制及预测提供新的参考。 展开更多
关键词 膨胀土 损伤 结构性 裂隙 力学表征 抗剪强度 三轴试验
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温度对地质聚合物胶凝体系激发特性的影响试验研究 被引量:7
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作者 白二雷 许金余 +1 位作者 周龙飞 马舒宁 《混凝土》 CAS CSCD 北大核心 2014年第1期65-67,共3页
为研究不同温度条件对地质聚合物胶凝体系激发反应特性的影响,选取矿渣和粉煤灰作为原材料制备了水胶比为0.31的地聚物胶凝体系,设计了不同温度的碱性反应溶液(10-90℃)和不同的养护温度(10-90℃),以此来分析温度对胶凝体系制... 为研究不同温度条件对地质聚合物胶凝体系激发反应特性的影响,选取矿渣和粉煤灰作为原材料制备了水胶比为0.31的地聚物胶凝体系,设计了不同温度的碱性反应溶液(10-90℃)和不同的养护温度(10-90℃),以此来分析温度对胶凝体系制备过程中的流变性能的影响和早期(24h)强度的影响。结果表明:矿渣粉煤灰胶凝体系的流变性能和24h抗折、抗压强度与温度密切相关,随温度的升高,其流变性能和24h抗折、抗压强度都是先增大后减小,流变性能的最佳温度在50℃左右,而强度的最佳温度则在60℃左右。 展开更多
关键词 地质聚合物 矿渣 粉煤灰 温度 流变性能 强度
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原子探针层析技术(APT)最新进展及应用 被引量:14
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作者 刘文庆 刘庆冬 顾剑锋 《金属学报》 SCIE EI CAS CSCD 北大核心 2013年第9期1025-1031,共7页
原子探针层析技术(APT)是具有原子尺度空间和质量分辨率的材料表征和分析手段.近几年来,在原子探针设备和数据软件分析技术方面有很大改善和进步.本文在介绍APT最新进展的基础上,以高强度低合金(HSLA)钢和铝合金为研究对象,讨论了APT在... 原子探针层析技术(APT)是具有原子尺度空间和质量分辨率的材料表征和分析手段.近几年来,在原子探针设备和数据软件分析技术方面有很大改善和进步.本文在介绍APT最新进展的基础上,以高强度低合金(HSLA)钢和铝合金为研究对象,讨论了APT在传统结构材料研究中的独特优势. 展开更多
关键词 原子探针层析技术 表征 高强度低合金钢 铝合金
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膨胀土损伤变量不同表征方法评价的试验研究 被引量:12
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作者 程明书 汪时机 +3 位作者 张雅倩 李贤 江胜华 陈正汉 《岩土力学》 EI CAS CSCD 北大核心 2015年第10期2892-2898,共7页
裂隙性是膨胀土的重要结构特征,裂隙损伤对膨胀土的变形、强度和稳定性有重要影响。岩土体损伤演化理论是当前研究的前沿课题,选择合理的损伤变量决定着损伤模型的正确性。为评价几种损伤变量表征方法的合理性,以南水北调中线工程陶岔... 裂隙性是膨胀土的重要结构特征,裂隙损伤对膨胀土的变形、强度和稳定性有重要影响。岩土体损伤演化理论是当前研究的前沿课题,选择合理的损伤变量决定着损伤模型的正确性。为评价几种损伤变量表征方法的合理性,以南水北调中线工程陶岔引水渠坡的膨胀土为试验研究对象,通过控制净围压和吸力分别为100、50 k Pa下的CT-三轴剪切试验,定量研究了分别基于承载面积、CT数的均值ME和方差SD的损伤变量表征方法的合理性。研究发现,损伤面积相同而损伤部位不同的试样偏应力-应变曲线和强度基本一致;损伤面积和SD可以作为损伤变量表征参数,而ME不适合用来表征膨胀土的损伤变量,虽然ME可以很好地用来定义岩石的损伤变量。试验研究结果可以为建立考虑损伤的膨胀土强度理论和本构模型中损伤变量的选择、定义提供科学依据。 展开更多
关键词 损伤变量 表征 评价 抗剪强度 CT-三轴试验
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透波氮化硅纤维的综合性能评价表征研究 被引量:4
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作者 张娟 周明星 +2 位作者 张敬义 周军 张大海 《宇航材料工艺》 CAS CSCD 北大核心 2019年第4期72-75,94,共5页
系统研究了氮化硅纤维的基本物理性能、力学性能和介电性能,并且探究了各性能的测试方法。结果表明,氮化硅纤维在1 500℃的高温强度保留率达到50%以上,介电常数为6.0左右,说明氮化硅纤维可以作为透波材料在苛刻的高温环境下长时使用。
关键词 氮化硅纤维 评价表征 力学强度 介电性能
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