共查询到20条相似文献,搜索用时 15 毫秒
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Sultana S. M. Nourin Pawar Shital Patangrao Kamkar Milad Sundararaj Uttandaraman 《Journal of Electronic Materials》2020,49(3):1588-1600
Journal of Electronic Materials - In this study, we achieved almost 99% (i.e., 19 dB) electromagnetic interference shielding effectiveness (EMI SE), at a much lower cost than... 相似文献
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The combined use of a highly magnetic filler (mumetal) in low proportion and a highly conductive filler in high proportion
in a polymer matrix provides a composite material that is more effective for electromagnetic interference shielding than the
use of a highly magnetic filler alone or the use of a highly conductive filler alone. Mumetal is effective (due to absorption)
when it is in a composite material of DC electrical resistivity below 10 Ω cm, as provided by conductive fillers, which contribute
to shielding by reflection and allow paths for eddy current. 相似文献
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《Electromagnetic Compatibility, IEEE Transactions on》1964,6(2):31-35
Although several proprietory finishes have been available for aluminum and magnesium protection from corrosion, the electrical properties at radio frequencies have never been sufficiently defined. In order to evaluate the relative merits of such finishes for aluminum and magnesium, a test program was established. Fixtures were designed to measure bonding impedance from dc to RF, and to evaluate shielding efficiency and insertion loss from gaskets used in joint interfaces. Marked differences in performance were observed between the radio frequency shielding obtained at radio frequencies and the bonding impedance measurements, indicating that the commonly used criterion of dc or RF bonding impedance is not sufficiently sensitive to provide good control of conductive coatings. Corrosion tests indicated several finishes would be acceptable from both the corrosion and electrical viewpoint. 相似文献
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导电衬垫在电磁屏蔽中的应用 总被引:2,自引:1,他引:1
文章分析了屏蔽体抑制电磁干扰失败的原因,指出了导电衬垫在抑制电磁干扰中的使用场合与作用。介绍了金属螺旋管、导电橡胶、金属丝网、指形簧片和导电布等五种常用导电衬垫的材料组成、性能和适用范围,并就其选择和安装问题作了探讨。 相似文献
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对于普通的无线网络用户来说,无线网络的使用需要同时兼顾便携、高速和安全的特性,因此IDS是一个重要的发展方向,但对于类似军队中的保密要求更高的应用来说,则需采用更加稳妥的解决方案。TIPTOP无线网络阻断系统使用电磁干扰技术,通过对2.4GWLAN无线通信网络(802.11b/g/n)进行干扰,能够达到全部或有选择性的阻断WLAN中无线接收器(Access Point)或个人工作平台(Station)的无线信道,同时采用了智能分析技术,一旦环境中出现无线信号,即对其进行干扰,并记录干扰结果,供需要时使用。 相似文献
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Fast and Rigorous Analysis of EMC/EMI Phenomena on Electrically Large and Complex Cable-Loaded Structures 总被引:2,自引:0,他引:2
Bagci H. Yilmaz A.E. Jian-Ming Jin Michielssen E. 《Electromagnetic Compatibility, IEEE Transactions on》2007,49(2):361-381
A fast and comprehensive time-domain method for analyzing electromagnetic compatibility (EMC) and electromagnetic interference (EMI) phenomena on complex structures that involve electrically large platforms (e.g., vehicle shells) along with cable-interconnected antennas, shielding enclosures, and printed circuit boards is proposed. To efficiently simulate field interactions with such structures, three different solvers are hybridized: (1) a time-domain integral-equation (TDIE)-based field solver that computes fields on the exterior structure comprising platforms, antennas, enclosures, boards, and cable shields (external fields); (2) a modified nodal-analysis (MNA)-based circuit solver that computes currents and voltages on lumped circuits approximating cable connectors/loads; and (3) a TDIE-based transmission line solver that computes transmission line voltages and currents at cable terminations (guided fields). These three solvers are rigorously interfaced at the cable connectors/loads and along the cable shields; the resulting coupled system of equations is solved simultaneously at each time step. Computation of the external and guided fields, which constitutes the computational bottleneck of this approach, is accelerated using fast Fourier transform-based algorithms. Further acceleration is achieved by parallelizing the computation of external fields. The resulting hybrid solver permits the analysis of electrically large and geometrically intricate structures loaded with coaxial cables. The accuracy, efficiency, and versatility of the proposed solver are demonstrated by analyzing several EMC/EMI problems including interference between a log-periodic monopole array trailing an aircraft's wing and a monopole antenna mounted on its fuselage, coupling into coaxial cables connecting shielded printed circuit boards located inside a cockpit, and coupling into coaxial cables from a cell phone antenna located inside a fuselage. 相似文献
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聚氨酯乳液/纳米石墨微片复合导电涂料的制备及其电磁屏蔽性能 总被引:3,自引:0,他引:3
以纳米石墨微片为导电填料,聚氨酯乳液为基体,制备水性导电复合涂料,研究其导电性能和电磁屏蔽性能。结果表明,质量分数为35wt%纳米石墨微片,粘度区间160~180MPa·s,质量分数为2%的OP-10分散剂为最佳配方,最佳施工工艺为超声波分散30min后喷涂,涂层厚度控制在80um左右,在65℃的条件下固化。通过该法制备得到的导电涂料,其涂层表面电阻率降低至7.5Ω·cm^-2,平均的电磁屏蔽效能在27dB左右(300kHz~1.5GHz)。 相似文献
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Markus Hallermann Ilka Kriegel Enrico Da Como Josef M. Berger Elizabeth von Hauff Jochen Feldmann 《Advanced functional materials》2009,19(22):3662-3668
Here, it is shown how carrier recombination through charge transfer excitons between conjugated polymers and fullerene molecules is mainly controlled by the intrachain conformation of the polymer, and to a limited extent by the mesoscopic morphology of the blend. This experimental result is obtained by combining near‐infrared photoluminescence spectroscopy and transmission electron microscopy, which are sensitive to charge transfer exciton emission and morphology, respectively. The photoluminescence intensity of the charge transfer exciton is correlated to the degree of intrachain order of the polymer, highlighting an important aspect for understanding and limiting carrier recombination in organic photovoltaics. 相似文献
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