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971.
Room-temperature time-differential perturbed-angular-correlation (TDPAC) spectra of 140Ce arising through 140Ba-140La from 140Cs in He-doped Fe, unannealed and annealed in vacuum at various temperatures, were obtained in order to examine whether Ce (or rather, La and Ba) and He form complexes having a definite geometrical structure in Fe, as suggested by first-principles density-functional theory calculations. No clear signal of such complexes was observed in the TDPAC spectra. However, the TDPAC spectra indicate that Ce and He form complexes having a variety of geometrical structures. Comparison with reported TDPAC results on 111Cd arising from 111In in He-doped stainless steel shows that the parent atoms (La and Ba) of 140Ce trap He atoms more efficiently than In atoms do, indicating stronger bonding of He to the former atoms, while different from the present case, 111Cd (In)–He complexes form a unique geometrical structure.  相似文献   
972.
Two Fe–Cu binary model alloys, Fe–0.3Cu and Fe–0.6Cu, were irradiated with fission neutrons at doses ranging from 4?×?10?6 to 0.16 dpa (displacements per atom) at ~573 K to investigate the formation of Cu precipitates and microstructural evolution. The Cu content only affected the formation of Cu precipitates and microvoids at low doses. In Fe–0.3Cu, the formation of microvoids and Cu precipitates initiated at doses of 1.2?×?10?4 and 4?×?10?5 dpa, respectively. On the other hand, the formation of microvoids started at a dose of 4?×?10?4 dpa in Fe–0.6Cu, and Cu precipitates were formed even after irradiation to 4?×?10?6 dpa. On further irradiation, the difference in the formation of Cu precipitates and microvoids was small. Microvoids grew with increasing irradiation dose up to 3?×?10?3 dpa in both alloys. Prominent aggregation of Cu atoms occurred upon irradiation from 3?×?10?3 to 1.6?×?10?2 dpa and the microvoids shrank. The Cu precipitates no longer grew, and microvoids nucleated and grew in the matrix above a dose of 1.6?×?10?2 dpa in both alloys. The present studies clearly reveal the relationships between the formation and growth of Cu precipitates and microvoids with irradiation dose.  相似文献   
973.
Industry and scholarly sources both argue that multiplayer gaming and competition are important factors in creating enjoyment, but relatively little empirical work demonstrates this claim. This study uses an experimental design (N = 139) to evaluate the effects of different multiplayer modes on enjoyment, allowing participants to interact naturally with a confederate partner and manipulating both game mode and partner behavior in a game of Madden '08. Results show that enjoyment is significantly enhanced by the combination of competitive play and a friendly partner, and demonstrate that the quality of interpersonal interaction only partly accounts for this.  相似文献   
974.
Individual choices are commonly taken to manifest personal preferences. The present study investigated whether social and statistical cues influence young children's inferences about the generalizability of preferences. Preschoolers were exposed to either 1 or 2 demonstrators’ selections of objects. The selected objects constituted 18%, 50%, or 100% of all available objects. We found that children took a single demonstrator's choices as indicative only of his or her personal preference. However, when 2 demonstrators made the same selection, then children inferred that it generalized to other agents of the same kind as the original demonstrator's, but not to agents of a different kind. Lastly, only when both demonstrators blatantly violated random selection (i.e., in the 18% condition) did children generalize the preference even to an agent of a different kind. Thus, from a young age, social and statistical cues inform children's naïve sociology.  相似文献   
975.
That different amplitudes of muscle activities during various abdominal exercises not only reflect the inherent differences in motor control but movement speed as well was hypothesized. 20 healthy adults (M age = 23 yr.) performed three exercises that involved varying amounts of trunk control: the partial sit-up, full sit-up, and AbSlide roll. Covariate analyses indicated that the amplitude of muscle activities could be partitioned into three categories: motor control and scaling (speed and amplitude), scaling only, and motor control only. Overall, the AbSlide exercise activated the most amount of muscular activity, followed by the full and partial sit-up exercises. Results are discussed in terms of how the various muscles contribute to motor control and velocity scaling.  相似文献   
976.
许宜兰 《宗教学研究》2006,1(3):177-181
洛阳汉代墓室壁画是中国的艺术瑰宝,是迄今发现的能够代表汉代绘画发展水平的杰作,其古拙的艺术风格和娴熟的绘画技法,对中国绘画艺术产生过积极影响,在中国美术史上占有极其重要的地位。本文旨在探讨洛阳汉墓壁画中表现的天人合一、阴阳五行的儒道思想观念。在那些形象生动、奇形怪状的绘画艺术背后,蕴藏了汉代先民对天地自然,对社会生活的理解,表达了他们对生命世界的永恒追求,展现了中国神秘文化的博大精深。  相似文献   
977.
Limitations of object-based feature encoding in visual short-term memory   总被引:4,自引:0,他引:4  
The present study investigated object-based feature encoding in visual short-term memory for 2 features within the same dimension that occur on different parts of an object. Using the change-detection paradigm, this experiment studied objects with 2 colors and objects with 2 orientations. Participants found it easier to monitor 1 rather than both features of such objects, even when decision noise was properly controlled for. However, no object-based benefit was observed for encoding the 2 features of each object that were of the same dimension. When similar stimuli were used but the 2 features of each object were from different dimensions (color and orientation), an object-based benefit was observed. These results thus impose a major constraint on object-based feature encoding theories by showing that only features from different dimensions can benefit from object-based encoding.  相似文献   
978.
Xu Y 《Perception》2002,31(11):1335-1347
In the present study, participants searched for a conjunction of color and orientation either from the same part of an object (same-part display), or from different parts of an object (different-part display). While no difference was found between the two display conditions in single feature searches, conjunction search in the same-part display was significantly faster than that in the different-part display. This same-part advantage applies to both the inner part as well as the outer part of an object. These results suggest that features are more readily integrated if they are from the same part of an object than if they are from different parts of an object. The formation of object part representations thus influences how features are integrated and encoded during visual information processing.  相似文献   
979.
Concept properties are an integral part of theories of conceptual representation and processing. To date, little is known about conceptual properties of abstract concepts, such as idea. This experiment systematically compared the content of 18 abstract and 18 concrete concepts, using a feature generation task. Thirty-one participants listed characteristics of the concepts (i.e., item properties) or their relevant context (i.e., context properties). Abstract concepts had significantly fewer intrinsic item properties and more properties expressing subjective experiences than concrete concepts. Situation components generated for abstract and concrete concepts differed in kind, but not in number. Abstract concepts were predominantly related to social aspects of situations. Properties were significantly less specific for abstract than for concrete concepts. Thus, abstractness emerged as a function of several, both qualitative and quantitative, factors.  相似文献   
980.
Minnesota Multiphasic Personality Inventory-2 (MMPI-2) results were compared in 118 psychiatric outpatients given standard instructions, instructions to exaggerate their problems, instructions to feign a disorder they did not have, or instructions to feign global psychological disturbance. The groups were comparable on demographic, occupational and diagnostic characteristics as well as intake MMPI-2 results. Experimental MMPI-2 results showed that clinical scales were generally elevated in the feigning groups, with only modest differences across dissimulating instruction sets. The feigning groups had reliably higher scores than controls on all overreporting indexes examined, although no significant differences between feigning groups were present for overreporting indexes. Classification rates using previously proposed cutting scores for outpatients on individual feigning indexes showed near perfect specificity, but low to at best moderate sensitivity. Multiple regression analyses indicated that Gough's (1954) Dissimulation Scale (Ds2) was most strongly related to feigning status, and no other feigning scale contributed a significant increment in predictive power once Ds2 was entered.  相似文献   
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