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81.
The roles chronological age and gender play in subjective time experience were explored in a sample of 294 adult men and women. Subjective time experience (STE: the difference between subjective age and chronological age) was found to vary widely among individuals, with some being "accurate" (SA = CA), and others either "retarded" (SA less than CA) or "advanced" (SA greater than CA). Males were more retarded in STE than females at every point in the lifespan, and patterns of age differences in adulthood differed for the two sexes as well. The results suggest that chronological age may play a key role in transitions in STE, and that chronological age is more significant in the STE of women than in the STE of men. 相似文献
82.
Farhad Shir Catherine Mavriplis Lawrence H. Bennett Edward Della Torre 《International Journal of Refrigeration》2005,28(4):1082
Results of a room temperature magnetic refrigeration test bed and an analysis using a computational model are presented. A detailed demonstration of the four sequential processes in the transient magnetocaloric regeneration process of a magnetic material is presented. The temperature profile during the transient approach to steady state operation was measured in detail. A 5 °C evolution of the difference of temperature between the hot end and the cold end of the magnetocaloric bed due to regeneration is reported. A model is developed for the heat transfer and fluid mechanics of the four sequential processes in each cycle of thermal wave propagation in the regenerative bed combined with the magnetocaloric effect. The basic equations that can be used in simulation of magnetic refrigeration systems are derived and the design parameters are discussed. 相似文献
83.
84.
Wenjun Liu Gene E. Ice Bennett C. Larson Wenge Yang Jonathan Z. Tischler J. D. Budai 《Metallurgical and Materials Transactions A》2004,35(7):1963-1967
The three-dimensional (3-D) X-ray crystal microscope is a new nondestructive tool for the 3-D characterization of the mesoscopic
and nanoscopic materials structure. A prototype microscope is installed on beamline 34-ID at the advanced photon source and
has begun initial operation. The prototype microscope has a routine spatial resolution of approximately 0.5 × 0.5 × 1 μm3 and can probe tens to hundreds of microns below a sample surface, depending on the composition of the sample. For each volume
element measured, the microscope can determine between 10 and 16 parameters. The measured parameters are the local crystallographic
phase (1 deg of freedom), the Eulerian angles of crystal orientation (3 deg of freedom), and the plastic and/or elastic strain-tensor
elements (6 to 12 deg of freedom). The time required to collect each volume element varies between 1 and 14 seconds, depending
on the precision of the parameters and the sample complexity. Much faster data acquisition and much better spatial resolution
are certain in the near future. Some initial results are presented to illustrate how the 3-D X-ray crystal microscope can
provide unprecedented information about the 3-D structure of materials.
This article is based on a presentation made at the symposium “Characterization and Representation of Material Microstructures
in 3-D” held October 8–10, 2002, in Columbus, OH, under the auspices of ASM International’s Phase Transformations committee. 相似文献
85.
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87.
Since 1961, there have been a total of seven patients with small bowel perforation caused by metastatic lung carcinoma reported in the literature. Perforation of the small bowel to metastatic lung carcinoma must be considered when evaluating older patients who have histories of heavy cigarette smoking and signs and symptoms suggestive of pulmonary neoplasia. Primary resection and end-to-end anastomosis of the perforated bowel is the treatment of choice. No patient with small bowel perforation secondary to lung carcinoma has survived more than four months. 相似文献
88.
将一水硬铝石矿和过饱和NaOH溶液及Ca(OH)2混合均匀后在微波炉中焙烧;熟料在稀碱性溶液、常压条件下进行浸出,研究配料比、微波焙烧和浸出条件对熟料浸出的影响。结果表明,升高微波焙烧温度、增加NaOH添加量或延长保温时间都可以增加熟料中铝的浸出率。增加Ca(OH)2添加量可以减少溶液中硅的溶解率,但过量添加Ca(OH)2反而导致铝的浸出效果下降。适当的浸出温度和浸出时间有助于减少二次反应发生,提高铝硅分离效果。在最优试验条件下,熟料中铝、钠、硅的浸出率分别达到96.7%、98.2%和7.05%,赤泥颗粒较大,利于过滤过程。 相似文献
89.
在实际调查的基础上,采用RS、CIS等高新技术相结合的方法对福建紫金山矿区的生态环境信息进行解译提取和分析对比。结果表明,紫金山矿山严发对矿区生态环境造成了一定程度的破坏,植被覆盖率降低.土地利用类型也发生了转变,土壤侵蚀作用增强,评价区周边侵蚀类型和强度变化不大。 相似文献
90.
Here we analyze the problem of determining whether experimentally measured spontaneous miniature end-plate currents (MEPCs) indicate that quanta are composed of subunits. The properties of MEPCs at end plates with or without secondary clefts at the neuromuscular junction are investigated, using both stochastic and deterministic models of the action of a quantum of transmitter. It is shown that as the amount of transmitter in a quantum is increased above about 4000 acetylcholine (ACh) molecules there is a linear increase in the size of the MEPC. It is possible to then use amplitude-frequency histograms of such MEPCs to detect a subunit structure, as there is little potentiation effect above 4000 ACh molecules. Autocorrelation and power spectral analyses of such histograms establish that their subunit structure can be detected if the coefficient of variation of the subunit size is less than about 0.12 or, if electrical noise is added, about 0.1. Positive gradients relate the rise time and half-decay times of MEPCs to their amplitude, even in the absence of potentiating effects; these gradients are shallower at motor nerve terminals that possess secondary clefts. The effect of asynchronous release of subunits is also investigated. The criteria determined by this analysis for identifying a subunit composition in the quantum are applied to an amplitude-frequency histogram of MEPCs recorded from a small group of active zones at a visualized amphibian motor-nerve terminal. This did not provide evidence for a subunit structure. 相似文献