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21.
The atomic structures of specific types of linear defects (phason lines) and planar defects (phason planes) in the complex metallic alloy phase ξ′-Al–Pd–Mn have been determined by high-resolution electron microscopy (HREM) and theoretical HREM simulation. The results show that a representational atomic structural model for phason planes can be constructed by introducing a shift between two parts of the perfect crystalline structure using a translation vector of r ?=?(1/2) a ?+?(1/2τ) c . This typical phason plane is normally parallel to the (001) plane of the ξ′-Al–Pd–Mn phase and consists of phason lines, which are arranged side-by-side with their linear direction parallel to the [010] axis. HREM simulations, based on the structural model for both edge-on and inclined types of phason lines, agree well with the experimental results. Taking into account the fact that the structural difference between various curved phason planes arises from the variation in the arrangement of individual phason lines, the atomic structures of the edge-on and inclined phason lines can be used to explain the various curved phason planes frequently observed in the ξ′-Al–Pd–Mn phase. 相似文献
22.
Four-phonon model of soft-matter quasicrystals is proposed, in which there are three solid phonons and one fluid phonon. With this model, the vibration spectrum of soft-matter quasicrystals can be obtained. The generalized Debye frequency, generalized Debye temperature and the thermodynamic functions of soft-matter quasicrystals are observed. The results on the specific heat of soft-matter quasicrystals demonstrate the contributions of both solid phonons and fluid phonon, respectively. 相似文献
23.
Yu Tian Zong Xin Guo Jie Ru Shi Yu Long Bian Pi Guo Han 《The Journal of psychology》2013,147(8):529-547
AbstractThis 1-year longitudinal study examined the bidirectional mediating role of loneliness in the association between shyness and generalized pathological Internet use (GPIU) in a sample of 291 Chinese university students (143 men, mean age =?19.07?years). A fully cross-lagged panel design was used in which shyness, loneliness, and GPIU were assessed at 3 time points separated by 6-month intervals (named T1, T2, and T3). The results indicated that relationships among shyness, loneliness, and GPIU were dynamic and bidirectional. Specifically, T1 shyness positively predicted increased T2 loneliness, T2 shyness positively predicted increased T3 loneliness, and T2 loneliness positively predicted increased T3 shyness. Additionally, T1 GPIU positively predicted increased T2 loneliness, T2 GPIU positively predicted increased T3 loneliness, and T2 loneliness positively predicted increased T3 GPIU. Loneliness was found to play a bidirectional mediating role in the association between shyness and GPIU. Specifically, T1 shyness and T3 GPIU were mediated through increased loneliness at T2, and T1 GPIU and T3 shyness were mediated through increased loneliness at T2. Furthermore, relationships among shyness, loneliness, and GPIU were the same across the 2 groups, with the strength of relationships being stronger for men. 相似文献
24.
Behavioral Family Therapy (BFT) generally targets four typical disruptive behaviors among children ages from 2 to 7 years: noncompliance, aggression, tantrums, and negative talk. This study tests the effect of BFT on 20 Chinese aggressive children (16 boys and 4 girls) who were assigned to a BFT group or a control group. The results showed that the children's level of aggression in the BFT group reduced significantly compared to that of the control group, and the gains were maintained at a 6-month follow-up. These findings support the use of BFT as a treatment modality for Chinese aggressive children. 相似文献
25.
Jin Xue Hua Shu Hong Li Wenling Li Xiaomei Tian 《Journal of psycholinguistic research》2013,42(5):433-450
The present study examined the developmental issue of cognitive factors that explain Chinese literacy. Phonological awareness, rapid automatized naming, short-term memory, orthographic awareness and morphological awareness and two literacy tasks (character naming and reading fluency) were administered to 408 second-graders, 428 fourth-graders and 496 six-graders. Results from linear regression analysis and path analysis model showed that the five reading-related cognitive constructs explained unique variances in character naming. Second, character naming is primary for reading fluency after controlling other cognitive constructs; third, the relation between the cognitive factors and literacy changes significantly as a function of reading skills. Results give a clear direction to understanding Chinese reading development. 相似文献
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27.
儿童社会认知发展的特点 总被引:6,自引:0,他引:6
社会认知是个体对社会性客体和社会现象及其关系的感知和理解活动。综合分析国内外已有研究,我们认为儿童社会认知发展具有如下主要特点:(1)儿童社会认知的发展是一个逐步区分认识社会性客体的过程;(2)儿童社会认知发展的核心体现是观点采择能力的发展:(3)儿童社会认知各方面的发展是非同步、不等速的;(4)儿童社会认知的发展具有认知发展的普遍规律.但不完全受认知发展的影响;(5)儿童社会认知的发展与社会交往密切相关。 相似文献
28.
Can We Dissolve Physical Entities into Mathematical Structures? 总被引:2,自引:0,他引:2
29.
以2009年对扬州市24个行政村的实地调查为基础,本文对社会主义新农村建设背景下农民集中居住的需求进行了考察。研究结果表明,有一定比例的农民具有明确的集中居住的需求,且文化程度较高、家庭收入主要来源于非农业、收入水平较高的农户集中居住的需求相对较强。但对大多数的经济欠发达地区而言,农民的文化程度相对较低,农业收入是主要的家庭收入来源,且农户的收入水平不足以支撑居住集中化过程中房屋搬迁和重建的相关费用时,比较适合农民生产和生活的居住形式还是村庄。 相似文献
30.
Jeanine Warisse Turner James D. Robinson Yan Tian Alan Neustadtl Pam Angelus Marie Russell Betty Levine 《人类交流研究》2013,39(2):252-268
This investigation examined the impact of social support messages on patient health outcomes. Forty‐one American Indian, Alaska Native, and Native Hawaiian patients received a total of 618 e‐mail messages from their healthcare provider (HCP). The e‐mail messages were divided into 3,565 message units and coded for instances of emotional social support. Patient glycosulated hemoglobin scores (HbA1c) showed significantly improved glycemic control and emotional social support messages were associated with significant decreases in HbA1c values. Patient involvement with the system, measured by system login frequency and the frequency of uploaded blood glucose scores to the HCP, did not predict change in HbA1c. 相似文献