Effect of sample size on ductility of metallic glass

With decreasing sample dimension, the compressive plastic strain of a Zr-based metallic glass increases from near zero to as high as 80% without failure. This indicates that macroscopically brittle or ductile deformation behaviour can occur in chemically and structurally identical metallic glass. A concept of critical shear offset is proposed to explain the strong size effect on the enhanced plasticity of metallic glass by taking the shear fracture energy density into account. This finding provides new understanding on the principle that for metallic glass ‘smaller is more ductile’, even on the macroscopic scale.     

New insights on tensile plasticity of ultrafine-grained metallic materials

ABSTRACT

The tensile properties of TiNi_43.5Fe_6.5 alloy samples having different grain sizes (0.16, 0.35, 1.7, 2.3, and 3.9?μm) and fabricated by severe plastic deformation and annealing were investigated. It was observed that both the strength and the elongation of the alloy increase with a decrease in the grain size until the average size reaches 1.7?μm. However, for average grain sizes smaller than 1.7?μm, the elongation decreases continuously with further grain refinement. On the other hand, the strain-hardening rate does not decrease with the decrease in plasticity but instead increases slightly. The poor ductility of the ultrafine-grained TiNi_43.5Fe_6.5 alloy is accompanied by a high degree of strain hardening. This newly observed ductility behaviour of the ultrafine-grained TiNi_43.5Fe_6.5 alloy is elucidated by characterising the intragranular and grain boundaries.     

基于属性层级结构的认知诊断测验的组卷

认知诊断测验组卷方法对提高被试属性掌握模式的判准率至关重要.Henson和Douglas的组卷方法(2005)得到的认知诊断测验判准率不高,没有考虑属性间的层级关系是重要原因.本文提出一种基于属性层级结构的认知诊断组卷方法:首先根据属性层级结构确定待选项目类集合,其次根据新建构的选题指标确定项目类,然后由属性区分被试的能力确定各项目类中题目的数量,并在测验Q阵中放入可达阵.模拟研究表明:新方法比H&D方法在判准率上有很大的提高;新的选题指标比H&D的指标大大缩短计算时间.     

The impact of role modeling on protégés' personal learning and work-to-family enrichment

The present study investigates the impact of role modeling as perceived by protégés on their personal learning (i.e., relational job learning and personal skill development) and work-to-family enrichment (WFE). Results from a two-wave field survey of 173 protégés in the People's Republic of China indicate that role modeling positively affects relational job learning and personal skill development. However, personal skill development rather than relational job learning was found to be positively related to WFE and to mediate the relationship between role modeling and WFE. The theoretical and managerial implications of these findings are discussed.     

伦理与审美的双重奏——儒家之礼的人类学解析

借鉴人类学关于仪式的研究成果,探讨传统儒家之礼对个体身心进行调节和实现社会整合的内在机制。儒家对礼进行建构的过程中,通过一系列具有审美意味的象征符号,展演了内在的伦理精神和道德理念,释放了个体的感性情感和欲望;通过赋予和强化个体的社会角色与身份,礼为个体生命的价值实现提供了一个构建意义的场域,同时也完成了对于个体的社会调控。     

利益相关者理论视野下的金融企业社会责任

2008年全面爆发的美国金融危机影响波及全球。从企业伦理或经济伦理的角度来看,此次金融危机的根源在于传统的股东利益至上理念的内在缺陷。本文提出用利益相关者理论替代股东利益至上理论。利益相关者理论强调企业应该考虑股东、员工、客户、合作伙伴、社区、政府、环境、经济共同体等各方利益相关者的权益。金融企业必须转变传统的经营理念,积极引进利益相关者理论,履行其所应承担的企业社会责任,此乃克服金融危机的一种可能的和有效的路径。     

Parental, Behavioral, and Psychological Factors Associated with Cigarette Smoking among Secondary School Students in Nanjing, China

We designed this study to assess parental, behavioral, and psychological factors associated with tobacco use among Chinese adolescents. The data were collected from 995 middle school students in Nanjing, China. Both smoking experimentation and current smoking (smoking in the past 30 days) were assessed among the study sample. Psychosocial measures include family structure, problem behaviors, social influence of smoking (both parental and friends’ approval of smoking), depressive symptoms, social alienation, self-esteem, parental monitoring (social monitoring and academic monitoring) and parenting style (responsiveness and demandingness). Among the study sample (mean age 15.16 years and 50% females), 24% ever smoked and 15% smoked in the past 30 days. Advanced age, male gender, low family SES, low school performance and low educational aspiration were associated with both smoking experimentation and current smoking. Depressive symptoms, social alienation, low self-esteem, low social and academic monitoring, problem behaviors, low maternal and paternal responsiveness, peer smoking, parent smoking, and parental and friends’ approval of smoking were positively associated with current smoking among Chinese adolescents. Future tobacco use prevention efforts among Chinese adolescents need to consider the parental, behavioral, and psychological correlates identified in the current study.     

论政治义务及其证成

公民的政治义务与国家的统治权利相对,是一种道德义务,不同于法律义务.政治义务问题是一组相关的问题,以公民为什么有服从义务为中心.义务与责任的区分对于政治义务问题意义重大.各种证成政治义务的进路都有问题,这把我们推向了无政府主义.     

Mortality of geriatric and younger patients with schizophrenia in the community

Little is known about the differences in mortality among non-institutionalized geriatric and younger patients with schizophrenia. In this study long-term mortality and suicidal behavior of all the geriatric (age > or = 65 years), middle-age (age 41-64 years), and young (age 15-40 years) subjects with schizophrenia living in a Chinese rural community were compared. A 10 year follow-up investigation among a 1994 cohort (n = 510) of patients with schizophrenia was conducted in Xinjin County, Chengdu, China. Compared with young subjects, geriatric subjects with schizophrenia were more likely to be female, have more previous physical illness, never accepted treatment, and practice religious (p < or = 0.01). There were no significant differences of suicide attempts among the three groups. Young subjects had a higher rate of suicide (1,033.8 per 100,000 person-years), and geriatric subjects had a higher rate of deaths due to other causes (accident and natural causes) (4,314.2 per 100,000 person-years). Standardized mortality ratios for both suicide and deaths due to other causes were highest in young subjects and the lowest in geriatric subjects. Patients with schizophrenia in all age groups had a marked increase in mortality and suicide. Specific intervention strategies for decreasing mortality and suicide should be developed for patients with schizophrenia in different age groups.     

重复学习对错误记忆通道效应的影响

本研究采用DRM范式以80名大学生为被试对错误记忆的通道效应进行了研究.实验采用三因素混合设计,运用信号检测论等方法探讨了重复学习对不同通道错误再认的影响.结果发现:1)汉语词表具有与英文词表不同的通道效应,表现为视觉学习的错误再认高于听觉学习;2)重复学习对视觉学习与听觉学习的错误再认产生分离性影响,即重复学习降低了视觉学习的错误再认,却提高了听觉学习的错误再认;3)信号检测论的分析表明:听觉学习在重复学习后对关键诱词的错误再认的增加是听觉学习对要义信息日益增加的敏感性连同较为宽松的提取标准协同起作用的结果.