排序方式: 共有32条查询结果,搜索用时 316 毫秒
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重载流无铠装多芯电缆周围磁场的特性可以用载流平行螺旋线理论模型来解释,而据此推导的简化计算公式可方便地估算电缆周围的磁场,为验证该理论模型的有效性和间化公式的准确度,对电缆周围的极低频磁场进行了基于毕奥-沙伐定律的数值计算和实测,通过数值计算结果和实测值与简化公式估算结果之间的比较,证明了该理论模型的有效性,发现简化计算公式对距电缆轴线0.2m以外的磁场有很高的估算精度,另外,还讨论了电缆所载电流的特性对周围磁场的影响,并提出一些降低多芯电缆系统周围磁场的方法。 相似文献
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In young chickens, the whole oil of nutmeg (200 mg/kg) increased the duration of sleep induced by ethanol (1--4 g/kg), particularly deep sleep. Iproniazid (50-400 mg/kg), a monoamine oxidase inhibitor, did not mimic this effect. 相似文献
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Consensus supertrees: The synthesis of rooted trees containing overlapping sets of labeled leaves 总被引:2,自引:2,他引:0
AD Gordon 《Journal of Classification》1986,3(2):335-348
Given two dendrograms (rooted tree diagrams) which have some but not all of their base points in common, a supertree is a dendrogram from which each of the original trees can be regarded as samples The distinction is made between inconsistent and consistent sample trees, defined by whether or not the samples provide contradictory information about the supertree An algorithm for obtaining the strict consensus supertree of two consistent sample trees is presented, as are procedures for merging two inconsistent sample trees Some suggestions for future work are made 相似文献
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5S及16S rDNA序列PCR扩增用于环境军团菌检测 总被引:3,自引:0,他引:3
军团菌病(Legionnaires’disease)是一种严重的空气传播疾病,在世界各地都常有报道,是由军团菌(Legionela)引起,该菌迄今已鉴定出了44个种,其中18种具致病性,最常见的导致严重病症的种有嗜肺军团菌(L.pneumophila... 相似文献
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Schunkert H König IR Kathiresan S Reilly MP Assimes TL Holm H Preuss M Stewart AF Barbalic M Gieger C Absher D Aherrahrou Z Allayee H Altshuler D Anand SS Andersen K Anderson JL Ardissino D Ball SG Balmforth AJ Barnes TA Becker DM Becker LC Berger K Bis JC Boekholdt SM Boerwinkle E Braund PS Brown MJ Burnett MS Buysschaert I;Cardiogenics Carlquist JF Chen L Cichon S Codd V Davies RW Dedoussis G Dehghan A Demissie S Devaney JM Diemert P Do R Doering A Eifert S Mokhtari NE Ellis SG Elosua R 《Nature genetics》2011,43(4):333-338
We performed a meta-analysis of 14 genome-wide association studies of coronary artery disease (CAD) comprising 22,233 individuals with CAD (cases) and 64,762 controls of European descent followed by genotyping of top association signals in 56,682 additional individuals. This analysis identified 13 loci newly associated with CAD at P < 5 × 10?? and confirmed the association of 10 of 12 previously reported CAD loci. The 13 new loci showed risk allele frequencies ranging from 0.13 to 0.91 and were associated with a 6% to 17% increase in the risk of CAD per allele. Notably, only three of the new loci showed significant association with traditional CAD risk factors and the majority lie in gene regions not previously implicated in the pathogenesis of CAD. Finally, five of the new CAD risk loci appear to have pleiotropic effects, showing strong association with various other human diseases or traits. 相似文献
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Quantum encounters of the cold kind 总被引:2,自引:0,他引:2
Since the introduction of laser-cooling techniques for neutral atoms in the early 1980s, the study of collisional interactions between atoms and molecules has been extended to the regime of ultracold temperatures. With nanokelvin temperatures now attainable, our ability to probe the interactions, both experimentally and theoretically, has also progressed. Understanding of the subtle and often highly quantum-mechanical effects that are manifest at such low energies has advanced to the point where new precision measurements are matched by highly accurate theoretical calculations. Low-energy phenomena such as Bose-Einstein condensation and the photoassociation of atoms into bound molecules are now accurately described with no free parameters. 相似文献