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151.
纳米技术在环境污染治理中具有广泛前景,然而其在应用过程中存在纳米颗粒及活性中心易团聚失活的问题。将纳米粒子的活性中心限制在载体的孔道内,构建出新型纳米限域材料可以有效克服这一缺点。同时,凭借材料的纳米限域效应,一定程度上可影响水的氢键网络结构,并会影响反应中中间活性粒子的演化、传质速率、晶体的生长和成核阶段过程,以及提高局部空间内反应底物的浓度。本文系统梳理了纳米限域材料的制备方法,并对比分析了各种制备方法的优缺点,归纳总结了近年来纳米限域材料在吸附和高级氧化降解污染物中的研究进展,展望了未来纳米限域材料在环境污染物治理领域的研发及应用前景。  相似文献   
152.
变幅加载条件下的疲劳寿命预测   总被引:3,自引:0,他引:3  
在疲劳累积损伤分析的基础上得出了对数累积损伤模型,阐明了变幅加载条件下疲劳损伤的累积特征和寿命预测方法。对数累积损伤模型作为—个失效判据,已在某中口径自动舰炮输弹簧的疲劳寿命预测中得到较满意的应用。研究表明,应力水平改变时,损伤因子D发生不连续变化是导致加载顺序效应的重要原因。  相似文献   
153.
在考虑受主炸药盖片对撞击入射冲击波衰减作用的基础上,得到了改进的飞片起爆计算模型,经与实验结果对比表明这一改进模型更符合实际系统。  相似文献   
154.
针对智能车辆队列横纵向控制及误差快速收敛问题,本文提出一种分布式横纵向有限时间滑模控制策略.首先,考虑跟踪误差的连锁反应及横纵向耦合效应,利用投影变换建立车辆队列横纵向误差模型,提出一种车辆队列横纵向控制框架.而后,针对误差快速收敛问题,设计非奇异积分终端滑模面(NITSM)与自适应幂次积分趋近律(APIRL),通过构...  相似文献   
155.
In order to explore the differing theoretical predictions of the cues-filtered-out perspective, SIDE model, and hyperpersonal model for online-to-offline relationships outside of the laboratory, a longitudinal survey study was conducted. Participants from a large online message board community who met up with an online acquaintance face-to-face completed surveys regarding their relationship with that individual before and after meeting their acquaintance face to face. Results indicated that the amount of communication with the online acquaintance was related to greater relation development whereas connection to the group was only related to greater individual closeness not satisfaction or predicted outcome value. In general the face-to-face meeting resulted in improved closeness, satisfaction, and predicted outcome value. An exploration for curvilinear effects as predicted by the hyperpersonal model revealed that predicted outcome value at time 1 had a curvilinear effect on closeness at time 2.  相似文献   
156.
用故障类型及影响分析法(FMEA),对宁夏石化公司二化肥循环水系统节能改造后的现状进行了调查分析,针对发现的问题提出了改进措施和建议。该分析方法有助于提早发现装置存在隐患,对预防事故发生、减少事故损失有重大意义。  相似文献   
157.
In recent studies, researchers have discovered a larger neural activation for stimuli that are more extreme exemplars of their stimulus class, compared with stimuli that are more prototypical. This has been shown for faces as well as for familiar and novel shape classes. We used a visual search task to look for a behavioral correlate of these findings regarding both simple geometrical shapes and more complex, novel shape classes. The latter stimulus set enabled us to control for the physical properties of the shapes, establishing that the effects are solely due to the positions of the particular stimuli in a particular shape space (i.e., more extreme versus more central in shape space) and not to specific shape features. The results indicate that finding an atypical instance of a shape class among more prototypical ones is easier and faster than the other way around. The prototypical status of a shape in our experiment could change very quickly, that is, within minutes, depending on the subset of shapes that was shown to the participants. Manipulating the degree of familiarity toward the shapes by selectively increasing familiarity for the extreme shapes did not influence our results. In general, we show that the prototypical status of a stimulus in visual search is a highly dynamic property, depending on the distribution of stimuli within a shape space but not on familiarity with the prototype. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
158.
This article addresses Simonsohn's (2011) critique of field studies of implicit egotism. We argue that Simonsohn provides no compelling theoretical reason to believe that implicit egotism should be valid only in the laboratory. In addition, we argue that a careful analysis of most of Simonsohn's studies of implicit egotism shows that they provide little or no power to reveal real effects of implicit egotism. We conclude that it is more constructive to try to identify theoretically derived moderators of implicit egotism than to try to document that it is always spurious in the field. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
159.
To study age effects in the resolution of idiomatic semantic ambiguity, we focus on decomposability, the extent to which a literal reading of an idiom's words shares meaning with its figurative interpretation. Younger and older adults judged whether decomposable and nondecomposable idioms and nonidioms had a literal interpretation. Older adults were slower at making literality judgments and more sensitive to conflicts between literal and figurative meanings. The results support claims of decompositional analysis of idioms during later processing stages and of obligatory activation of figurative meanings. They also lend support to research that has shown age-related effects in ambiguity resolution. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
160.
A series of eye-tracking and categorization experiments investigated the use of speaking-rate information in the segmentation of Dutch ambiguous-word sequences. Juncture phonemes with ambiguous durations (e.g., [s] in 'eens (s)peer,' “once (s)pear,” [t] in 'nooit (t)rap,' “never staircase/quick”) were perceived as longer and hence more often as word-initial when following a fast than a slow context sentence. Listeners used speaking-rate information as soon as it became available. Rate information from a context proximal to the juncture phoneme and from a more distal context was used during on-line word recognition, as reflected in listeners' eye movements. Stronger effects of distal context, however, were observed in the categorization task, which measures the off-line results of the word-recognition process. In categorization, the amount of rate context had the greatest influence on the use of rate information, but in eye tracking, the rate information's proximal location was the most important. These findings constrain accounts of how speaking rate modulates the interpretation of durational cues during word recognition by suggesting that rate estimates are used to evaluate upcoming phonetic information continuously during prelexical speech processing. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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