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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
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906.
Cong Liu Feng An Paria S M Gharavi Qinwen Lu Junkun Zha Chao Chen Liming Wang Xiaozhi Zhan Zedong Xu Yuan Zhang Ke Qu Junxiang Yao Yun Ou Zhiming Zhao Xiangli Zhong Dongwen Zhang Nagarajan Valanoor Lang Chen Tao Zhu Deyang Chen Xiaofang Zhai Peng Gao Tingting Jia Shuhong Xie Gaokuo Zhong Jiangyu Li 《国家科学评论(英文版)》2020,7(1):84
Complex oxides with tunable structures have many fascinating properties, though high-quality complex oxide epitaxy with precisely controlled composition is still out of reach. Here we have successfully developed solution-based single-crystalline epitaxy for multiferroic (1-x)BiTi(1-y)/2FeyMg(1-y)/2O3–(x)CaTiO3 (BTFM–CTO) solid solution in large area, confirming its ferroelectricity at the atomic scale with strong spontaneous polarization. Careful compositional tuning leads to a bulk magnetization of 0.07 ± 0.035 μB/Fe at room temperature, enabling magnetically induced polarization switching exhibiting a large magnetoelectric coefficient of 2.7–3.0 × 10−7 s/m. This work demonstrates the great potential of solution processing in large-scale complex oxide epitaxy and establishes novel room-temperature magnetoelectric coupling in epitaxial BTFM–CTO film, making it possible to explore a much wider space of composition, phase, and structure that can be easily scaled up for industrial applications. 相似文献
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908.
The validity of the Kaufman Assessment Battery for Children (K-ABC) (Kaufman & Kaufman, 1983) was investigated with a sample of preschool-age children. The sample consisted of 50 subjects aged 21/2 through 4 who were distributed roughly equally by age, sex, and race according to the 1980 census. The validity of the K-ABC was examined using the Slosson Intelligence Test (SIT) (Slosson, 1982) and the Classroom Behavior Inventory-Preschool Form (CBI) (Schaefer & Edgerton, 1978) as criterion measures. The SIT and CBI-Preschool Form Verbal Intelligence Scale were found to correlate significantly (p<.01) with the global scales of the K-ABC. The K-ABC did not differentiate between age or sex groups, but blacks scored lower than whites. The findings are supportive of previous validity studies (Kaufman & Kaufman, 1983) and two-factor theories of intelligence (e.g., Das, Kirby, & Jarman, 1975). 相似文献
909.
Seventeen deaf children and a matched group of 17 nonhearing impaired children were assessed to compare rate of basic concept development. The results indicate that deaf children scored approximately two standard deviations below their matched nonhearing impaired peers. Additionally, the deaf children exhibited a relatively flat subtest proffle, suggesting that basic concepts that have not been specifically taught remain uniformly delayed for deaf children. 相似文献
910.
Frederick A. Hadd 《Psychology in the schools》1986,23(4):361-364
Results of the TONI, WISC-R, and WRAT were compared for a sample of 66 learning disabled children: 51 males (32 white, 19 black) and 15 females (9 white, 6 black) whose mean age was 9–5 (SD = 1–10). The mean score of the TONI was significantly different from the Performance IQ. Nonsignificant differences were found between the TONI and Full Scale IQ and between the TONI and Verbal IQ. Correlation coefficients between the TONI and WISC-R ranged from a low of .35 for the Verbal IQ to .44 for both the Full Scale and Performance IQs. The correlation coefficients between the TONI and standard scores of the WRAT were .38, .27, and .23, for Reading, Spelling, and Arithmetic, respectively. Implications of these findings are discussed. 相似文献