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131.
132.
Yukun Sun 《科学通报(英文版)》2000,45(23):2203-2208
The history of homologous linear rule investigation is reviewed simply. The author puts forward a problem worth paying attention
to in the recent potential homologous linear rule investigation, especially some mistakes made in these investigations on
mathematical foundations. The author also exposes the mathematical arbitrariness of some papers on their potential homologous
linear rule investigation. 相似文献
133.
A series of lattice inversion pair potentials are used to evaluate the phase stability and site preference for uranium intermetallics UMxAl12-x (M = Fe, Co, Ni, Cr and Mn) and their related hydrides. Calculated results show that Fe, Co, Ni, Cr or Mn atoms preferentially substitute Al at the 8f site. Interstitial H atoms only occupy 2b interstitial sites in UMxAl12-x. Calculated lattice constants are found to agree with a report in the literature. Elastic constants and bulk modulus of UMxAl12-x and UMxAl12-xH were also investigated. In particular, the phonon densities of states (DOS) of these actinide compounds were evaluated for the first time. 相似文献
134.
The present study investigated neural mechanisms of moral judgment of lying in adults using high-density event-related potentials (ERPs). Participants were recruited to do moral judgment of 200 stories including two types of lying and their corresponding truth-telling. The results showed that both types of lying were judged more negative than their corresponding truth-telling, and moral judgment of black lying was more negative than that of modest lying. There were two main components of the ERPs evoked by the test stimuli. One was an early component, peaking at about 200 ms, and the other was a late component, peaking at about 400 ms. Over the frontal scalp sites, the early component was positive and the late component was negative, while they both reversed over the posterior sites. The ERPs of both types of lying was more positive than that of their corresponding truth-telling in the time window of 600—900 ms at the posterior sites. 相似文献
135.
目的:探讨超声心动图对心肌致密化不全的诊断价值。方法:重点观察心室近心尖1/3的心肌与心内膜。彩色多普勒血流检测时降低量程,以便更好显示隐窝间隙的低速血流。结果:所有28例患者超声心动图检查均可见心腔内异常突起、粗大的肌小梁和其间的隐窝影像,24例为左室型,4例双室型。26例伴有充血性心力衰竭症状。4例左室内血栓形成。结论:超声心动图是诊断该病的重要手段,具有特征性意义。 相似文献
136.
该文通过对晚稻和大豆的自然供水条件分析表明:大豆比晚稻具有更明显的节水效能,江西省某些干旱严重的地区可以在伏秋季节改晚稻种植为大豆种植,这样可取得较好的经济效益。 相似文献
137.
David Damanik 《Journal of Mathematical Analysis and Applications》2005,303(1):327-341
Following the Killip-Kiselev-Last method, we prove quantum dynamical upper bounds for discrete one-dimensional Schrödinger operators with Sturmian potentials. These bounds hold for sufficiently large coupling, almost every rotation number, and every phase. 相似文献
138.
139.
Local four-dimensional tensor decomposition formulae for generic vectors and 2-tensors in spacetime, in terms of scalar and antisymmetric covariant tensor potentials, are studied within the framework of tensor distributions. Earlier first-order decompositions are extended to include the case of four-dimensional symmetric 2-tensors and new second-order decompositions are introduced. 相似文献
140.
针对嵌入原子势,提出了1种新的并行分子动力学算法--作用力分解算法.并与另外2种并行算法进行了比较.作用力分解算法并行代码编写简单,不要求模拟区域具有规则形状.而测试并行后的速度表明,当计算的原子数目小于104数量级时,它是最佳的并行算法. 相似文献