英文阅读材料的颜色对阅读成绩的影响

该文通过档案调查、实验和问卷调查的方法就大学英语六级考试中不同颜色文字对阅读成绩的影响进行了探索。在对北京大学和北京师范大学的2007年12月的5537份六级考试成绩档案的调查过程中,发现不同颜色试卷的阅读部分和总分成绩差异显著(蓝色低于黑色),但是这种差异并不大;选取26名被试进行实验的结果发现,题目难度和颜色之间存在边缘显著的交互作用,简单题目上蓝色比黑色成绩更低,但是这种差异在复杂题目上没有那么明显。进一步地,通过131份问卷调查数据得出,被试的阅读习惯为黑色,主观偏好也为黑色:这也是影响阅读成绩的主要因素。     

Thermal shock resistance of brittle ceramic materials with embedded elliptical cracks

An analytical model is established for the prediction of the thermal shock resistance of a ceramic plate with an embedded elliptical crack with ideal thermal insulation. The thermal stress intensity factors at the crack fronts are formulated by fitting the thermal stress to a polynomial form in an un-cracked plate. The thermal shock resistance of sapphire ceramic is evaluated as an example. In addition, the numerical solution of thermal shock resistance suitable for practical engineering applications is provided. The model developed applies to any brittle material in high temperature applications.     

On convergence of the generalized Maxwell scheme: conductivity of composites containing cubic arrays of spherical particles

The Maxwell concept of equivalent inhomogeneity generalized to account for the interactions between the particles in the cluster and combined with recently reported results on the polarizability of a cube is used to evaluate the effective conductivities of the materials reinforced by cubic arrays of spherical particles. New numerical results demonstrate that the estimates of the effective properties based on the generalized Maxwell scheme with the equivalent inhomogeneity of cubic shape converge to the accurate periodic benchmark solutions, unlike spherical shape-based estimates.     

Independent use of activity materials by the elderly in a residential setting

A lottery was implemented to encourage the elderly clients of a residential home to use activity materials any time they wished, independently of staff intervention and the institutional routine of the home. During baseline, there were minimal levels of independent use of activity materials by residents. Various conditions were implemented but only the introduction of a £20 lottery prize brought about a significant increase in the frequency of independent use of activity materials. A follow‐up suggested that the reinforcing properties of the activity materials themselves eventually maintained the target behavior.     

Acting on one's attitudes: Procedures for linking attitude and behavior

Two investigations examined the determinants of correspondence between attitudes and behaviors. The first investigation examined the relationship between previously measured attitudes toward affirmative action and subsequent behavioral verdicts in a sex discrimination court case. In this basic situation, correspondence between measured attitudes and judicial decision-making behavior was minimal, for both low-self-monitoring individuals and high-self-monitoring individuals. Increasing the availability of attitudes generated substantial correspondence between attitudes and behavior for low-self-monitoring individuals, but not for high-self-monitoring individuals. Increasing the relevance of attitudes generated substantial correspondence between attitudes and behavior for both low-self-monitoring individuals and high-self-monitoring individuals. The second investigation examined the decisions of individuals with favorable attitudes toward psychological research to volunteer to participate in extra sessions of a psychology experiment. Once again, increasing the relevance of attitudes was an effective procedure for inducing individuals to translate existing attitudes into corresponding behaviors. These empirical outcomes are interpreted within a theoretical framework that specifies the interactive contributions of availability, relevance, and self-monitoring to the creation of “action structures” that link attitudes and behavior. Practical implications of this viewpoint are discussed.     

从毕生发展的角度看个体分类倾向的两次转变——材料的生命性和可操作性的作用

研究从毕生发展的视角考察了个体分类倾向的发展轨迹,并探讨任务材料内容可能对其产生的影响。选取幼儿园、小学、中学、大学和中老年个体各30名作为研究对象,记录他们面对不同的分类材料(有/无生命、高/低可操作性)的分类倾向。结果表明个体的分类倾向经历了两次转变:(1)进入小学后主题分类倾向逐渐降低,并在2、3年级时最低;(2)进入中学之后,个体逐渐恢复对主题分类倾向的偏好,中学和大学的个体面对含有生命体或是可操作性高的材料会比面对非生命体或可操作性低的材料时,更倾向于使用主题分类的策略。这一结果表明,个体对不同材料内容的分类倾向的发展轨迹存在差异,研究结果有助于理解个体概念组织的形成和发展过程。     

Synthesis of a single phase of high-entropy Laves intermetallics in the Ti–Zr–V–Cr–Ni equiatomic alloy

The high-entropy Ti–Zr–V–Cr–Ni (20 at% each) alloy consisting of all five hydride-forming elements was successfully synthesised by the conventional melting and casting as well as by the melt-spinning technique. The as-cast alloy consists entirely of the micron size hexagonal Laves Phase of C14 type; whereas, the melt-spun ribbon exhibits the evolution of nanocrystalline Laves phase. There was no evidence of any amorphous or any other metastable phases in the present processing condition. This is the first report of synthesising a single phase of high-entropy complex intermetallic compound in the equiatomic quinary alloy system. The detailed characterisation by X-ray diffraction, scanning and transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the existence of a single-phase multi-component hexagonal C14-type Laves phase in all the as-cast, melt-spun and annealed alloys. The lattice parameter a = 5.08 Å and c = 8.41 Å was determined from the annealed material (annealing at 1173 K). The thermodynamic calculations following the Miedema’s approach support the stability of the high-entropy multi-component Laves phase compared to that of the solid solution or glassy phases. The high hardness value (8.92 GPa at 25 g load) has been observed in nanocrystalline high-entropy alloy ribbon without any cracking. It implies that high-yield strength (~3.00 GPa) and the reasonable fracture toughness can be achieved in this high-entropy material.     

Teaching Beginning Braille Reading Using an Alphabet or Uncontracted Braille Approach

This study examined the effects of using a research based print reading program modified to accommodate beginning braille readers using an alphabet or uncontracted braille reading approach with five beginning braille readers. Four of the 5 participants displayed a clear increase in their ability to read high frequency words when they began using the Early Steps reading program modified to an Early Steps Alphabet Braille Reading Program. Study findings indicate that access to reading activities and materials afforded to sighted peers resulted in improved reading outcomes for children with visual impairments. Teachers, participants, and family members all viewed the use of the uncontracted braille reading program and materials favorably. Specialized reading instruction was also perceived as beneficial by teachers of students with visual impairments when the training addressed the specific needs of braille readers.     

Inhibition of endogenous carbon monoxide production induces transient retention losses in the day-old chick when trained using a single trial passive avoidance learning task

Carbon monoxide (CO) is most often thought of as an exogenous toxin rather than as a possible endogenous nootrope. However, a limited number of studies have suggested that CO is necessary in memory processing for at least some tasks. While nitric oxide (NO) and CO are known activators of guanylyl cyclase (GC), only the effect of NO on GC has been extensively investigated as a mechanism underlying memory processing. The aim of the present study was to determine if inhibition of CO production would have an effect on memory processing. Using chicks trained on a single trial passive avoidance task, inhibition of CO production using zinc (II) deuteroporphyrin IX 2,4-bis ethylene glycol (ZnBG; 5 microM) resulted in two transient retention losses occurring at around 40 and 130 min post-training. The timing of these transient retention losses was similar to those observed following inhibition of GC, using the same species and task in a previous study. This supports the notion that CO is necessary in memory processing for this task and may act through a GC-dependent mechanism. As ZnBG also directly inhibits GC or nitric oxide synthase (NOS) at high concentrations, a second experiment was carried-out to confirm the specificity of ZnBG for heme oxygenase (HO) at the concentration used. The action of ZnBG was challenged with the HO agonist hemin (100 microM) and the transient deficits were abolished. This confirmed that the action of ZnBG on memory was through a CO-related mechanism rather than directly on GC or NOS. In this way the specificity of ZnBG (5 microM) for HO could be confirmed. The results support a role for endogenous CO in memory processing, possibly through activation of GC. In addition, the transient retention losses observed following administration of ZnBG suggest that CO may be necessary for memory retrieval and not formation as previously thought.     

Tensile deformation mechanisms of the hierarchical structure consisting of both twin-free grains and nanotwinned grains

A series of large-scale molecular dynamics simulations have been performed to investigate the tensile properties and atomistic deformation mechanisms for the nanostructured Cu with three typical microstructures: the hierarchical structure consisting of both twin-free grains (d?=?70?nm) and grains with bundles of smaller nanotwins (d?=?70?nm, λ?=?10?nm), the fully nanograined structure and the fully nanotwinned structure. The average flow stress of the hierarchically structure is found to be higher than that calculated by rule of mixture. As compared with that of fully nanograined structure, the strength for the twin-free grains in the hierarchical structure is promoted and gives extra hardening due to the increased dislocation density and dislocation behaviours. It is also found that the nanotwin bundles are more deformable than the twin-free grains in the hierarchical structure according to the deviatoric strain invariant contour. This indicates that the fully nanograined structure cannot only be strengthened to a higher level, but also obtain better ductility by embedded with stronger bundles of smaller nanotwins. Thus, a superior strength–ductility synergy could be obtained in this kind of hierarchical structures, and this novel strategy has also been implemented in bulk austenitic steels or copper by recent experiments.