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61.
1 INTRODUCTIONTheorthorhombicalloysareofgreattech nolog icalinterestinhightemperatureapplicationssincetheyhaveagoodbalanceamongst 相似文献
62.
LI Yundong ZHANG Tianxiang ZHENG Zhi ZHU Yaoxiao Institute of Metal Research Academia Sinica Shenyang China Professor Institute of Metal Research Academia Sinica Shenyang China 《金属学报(英文版)》1990,3(6):393-397
The solid solubilities of 15 common alloying elements added to the Ll_2-type intermetalliccompound Ni_3Si at 900°C have been estimated,and their substitution modes have been de-duced from the direction of solubility lobe of the compound.It is shown that the alloyingbehaviours in Ni_3Si are determined by both size and electronic factors,i.e.,the substitutionmode is governed by electronic configuration and solubility by the both.An interactionparameter is presented to describe quantitatively the influence of electronic configuration onsubstitution mode and the solubility limit can be successfully explained together with atom radius. 相似文献
63.
大学生求学满意度实证研究--某高校学生个体特征对满意度单项要素的影响分析 总被引:1,自引:0,他引:1
求学满意度,又称为求学满意程度,它取决于教育需求主体对教育服务的预期同其实际所感知的教育服务水平的对比。教学计划、教学组织、教师教学、教学设施、校园环境、学生5知识技能等都是影响求学满意度的因素。本文在调查取得基本数据的基础上,使用相关的统计检验方法,分析了性别、生源地和不同年级这些学生个体地征对求学满意度单项要素的影响。主要结论有:学生性别差异对满意度单项要素的影响基本是随机的;不同生源地的学生对教学计划和管理制度两个要素的评价具有差异;不同年级的学生对教学设施和知识掌握程度的评价具有显著性差异;学生对学校服务评价单项因素差异很少,总体满意度在一定程度上反应学校的实际情况。 相似文献
64.
La在KCl-NaCl和LaCl_3-KCl-NaCl熔体中的溶解行为SCIEI 总被引:1,自引:0,他引:1
本文利用透明槽技术、电化学循环V-A法及量子化学EHMO三种方法,研究了La在KCl-NaCl(1:1mol)及LaCl_3-KCl-NaCl熔体中的溶解行为。初步认为:溶解在KCl-NaCl熔体中的La是以中性金属状态存在。在LaCl_3-KCl-NaCl熔体中,溶解的La与La^(3+)作用生成低价La^(2+)离子,La^(2+)又与周围的La^(3+)作用形成原子簇离子La_m^(n+)赋存于熔体之中。 相似文献
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66.
碱性电镀光亮锌镍合金研究 总被引:3,自引:1,他引:3
研究了镀液的组成与镀层中镍含量、镀层的相结构以及阴极电流效率的关系。提出了碱性电镀光亮锌镍合金的最佳镀液组成和工艺规范,并对茴香醛、四乙烯五胺和ZN—A5添加剂的吸附行为及其对锌镍电沉积过程的阻化作用进行了探讨。 相似文献
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应用粘弹谱仪考察了不同摩尔质量的聚酯(PET、PBT、PBT/PET)的动态力学性能,结果表明摩尔质量增大将提高其模量,但亦导致结晶速度变慢,使测得的模量反而比摩尔质量较低的试样小. 相似文献
69.
Effect of substrate on the risk of being washed away by floods for the Groundhoppers Tetrix subulata and Tetrix tenuicornis (Orthoptera: Tetrigidae)
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Inundation zones of rivers are risky environments for terrestrial animals because of the regular or irregular occurrence of floods. Although animals in these zones have evolved several strategies to survive floods, behavioural anti‐flooding strategies have seldom been studied but could play an important role in their life history strategies. We previously reported that the groundhopper Tetrix tenuicornis moves to dense vegetation in response to low atmospheric pressure (which may signal rain and flooding) but prefers mossy microhabitats and bare ground under high atmospheric pressure. In the current study, we found that the ability of the semi‐aquatic groundhoppers T. tenuicornis and Tetrix subulata to withstand direct water flow was greater in patches of dense vegetation than in patches of moss or on bare ground. Even a relatively low water velocity led to water transport (presumably passive) of both species, perhaps because they lack arolia or other adhesive devices on their tarsi. This morphological limitation precludes vertical migration on vegetation, which is a common anti‐flooding strategy in insects. Our results suggest that, by moving to dense vegetation in response to drops in atmospheric pressure, groundhoppers may reduce their risk of being washed away by floods. 相似文献
70.
Brad Nicholson 《Ergonomics》2014,57(9):1353-1365
Situational awareness is recognised as an important factor in the performance of individuals and teams in dynamic decision-making (DDM) environments (Salmon et al. 2014). The present study was designed to investigate whether the scores on the WOMBAT? Situational Awareness and Stress Tolerance Test (Roscoe and North 1980) would predict the transfer of DDM performance from training under different levels of cognitive load to a novel situation. Participants practised a simulated firefighting task under either low or high conditions of cognitive load and then performed a (transfer) test in an alternative firefighting environment under an intermediate level of cognitive load. WOMBAT? test scores were a better predictor of DDM performance than scores on the Raven Matrices. Participants with high WOMBAT? scores performed better regardless of their training condition. Participants with recent gaming experience who practised under low cognitive load showed better practice phase performance but worse transfer performance than those who practised under high cognitive load.Practitioner Summary: The relationship between task experience, situational awareness ability, cognitive load and the transfer of dynamic decision-making (DDM) performance was investigated. Results showed that the WOMBAT? test predicted transfer of DDM performance regardless of task cognitive load. The effects of cognitive load on performance varied according to previous task-relevant experience. 相似文献