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101.
��Сǿ������Զ��κ���裬�����ϣ������ 《核聚变与等离子体物理》2018,38(3):315-322
针对聚变工程大型超导导体样品在高场下的性能测试需求,设计了内径0.6m、磁场13T的背景磁体系统。磁体系统由6层12个分离式超导线圈组成,线圈采用常规的螺线管结构,由外至内分别使用NbTi、Nb3Sn和YBCO三种超导材料绕制而成;在直径500mm的测试区域范围内产生最高达13.22T的背景磁场,均匀性不低于95%。介绍了磁体线圈主要设计参数,用有限元软件完成电磁、结构分析。结果表明,设计合理可靠,能够满足导体测试装置的需求。 相似文献
102.
The reaction of metallic bismuth with either tungsten tetrachlorideoxide WOCl4 at 650 K or tungsten tetrabromideoxide WOBr4 at 670 K, respectively, leads to BiX2[W2O2X6] (X = Cl, Br) as black, lustrous crystal needles. The crystal structure determinations (triclinic, P$\bar{1}$ ) show the two isotypic structures to be closely related to Hg0.55[W2O2Cl6] with the presence of 1D‐polymeric W2O2X6 double strands. Dinuclear [Bi2X4]2+ cations are embedded in the host structure via secondary W–X ··· Bi bonds. Unlike the other members of theMy[W2O2X6] structure family, which crystallize monoclinic and show crystallographic equivalent tungsten atoms, BiX2[W2O2X6] has independent tungsten sites. Nevertheless, an assignment of an individual oxidation state to the tungsten atoms within the W2 group (W–W 2.8321(4) Å for X = Cl, 2.8985(4) Å for X = Br) is not possible and a dynamic intervalent state W(IV, V) is assumed. Electrical conductivity measurements for BiCl2[W2O2Cl6] show semi‐conductive behavior with a very small band gap of 70 meV and a high conductivity of around 0.5 Ω–1cm–1 at temperatures above 220 K. A temperature dependence of the activation energy of charge transport is present and interpreted by the Varshni model. 相似文献
103.
104.
《代数通讯》2013,41(10):3937-3953
Abstract This paper investigates coherent-like conditions and related properties that a trivial extension R ? A ∝ E might inherit from the ring A for some classes of modules E. It captures previous results dealing primarily with coherence, and also establishes satisfactory analogues of well-known coherence-like results on pullback constructions. Our results generate new families of examples of rings (with zerodivisors) subject to a given coherent-like condition. 相似文献
105.
We explicitly explain how to fix a wrong statement in a preliminary result of our previous paper on the conductor at a multiplanar singularity. 相似文献
106.
H. Kono X. Wang H. Ueda A. Ishiyama T. Saitoh Y. Aoki M. Yagi S. Mukoyama N. Fujiwara 《Physica C: Superconductivity and its Applications》2010,470(20):1334-1337
In high temperature superconductor applications used in electric power devices, YBCO coated conductors may be subjected to short-circuit fault-currents that are 10–30 times the normal operating current. These over-currents cause heat generation, resulting in Ic degradation of the YBCO coated conductor. Therefore, it is necessary to fully investigate the degradation characteristics of YBCO coated conductors. We previously conducted preliminary experiments on the degradation of YBCO sample tapes resulting from the over-current pulse drive. 相似文献
107.
The static and dynamical local spin susceptibility of the nonstoichiometric organic conductor, κ-(BEDT-TTF)4Hg2.78Cl8, is studied by 13C NMR spectroscopy from room temperature down to 1.7 K. We observe a gradual growth of inhomogeneity in the spin state as a spectral broadening down to the lowest temperature, which is sustained even under 0.4 GPa but suppressed under 0.8 GPa. The emergence of the inhomogeneity is discussed in the light of the doped triangular-lattice Mott insulator. 相似文献
108.
109.
Electromagnetic scattering from an infinite and a finite length PEMC circular cylinder, illuminated by an arbitrarily oriented
dipole, is investigated theoretically. An electric dipole as a source of excitation is considered first, and then a magnetic
dipole as a source of excitation is treated. In contrast to the case of an axially directed dipole, it is shown that no additional
terms are needed to incorporate the cross-polarized component of the field for the case of radial and circumferential dipoles.
Numerical verifications are presented to verify the validity of derived results and numerical code by comparing results with
the published literature.
相似文献
110.
为了掌握线路的振动状态,确定线路抗振能力,保证线路安全,需要明确架空输电导线的风致振动响应.本文针对江苏境内某特高压工程LGJ-630/45型导线,建立其振动控制能量平衡方程,编制了Fortran程序以高效准确地求解该超越方程,计算分析了单导线及四种分裂导线微风振动状态下的振动及耗能特性.结果表明,单导线在风振平衡点处的双振幅最大值在最低频率上,约为导线直径的两倍;四种分裂导线风振平衡点处的幅值在15Hz附近达到最大值;导线单位长度功耗在60Hz附近达到最高,功耗能力在较低频域(10Hz~20Hz)上较弱,在较高频域(30Hz~80Hz)较强;导线分裂数越大,分裂导线的振幅越小,八分裂导线的防振消振效果相对最好;四种分裂导线在在10Hz~20Hz频域振动幅值大而单位功耗水平低,因此10Hz~20Hz频段是分裂导线的危险频段,防振措施应该针对这一频段设置.研究方法与成果为LGJ-630/45导线的抗振设计提供了科学依据. 相似文献