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电感与微带片导电胶互联失效分析及解决办法 被引量:2
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作者 阴磊 孙玉达 +2 位作者 吴红 李红伟 莫秀英 《电子工艺技术》 2018年第2期98-100,共3页
在微波电路装配中,漆包线电感与微带片之间采用导电型胶粘剂粘结互联。由于导电型胶粘剂长期暴露空气中易产生氧化,粘结处易发生电阻值增大甚至裂缝现象,因此存在互联可靠性降低的问题。通过微点焊技术对漆包线电感进行微点焊互联,改善... 在微波电路装配中,漆包线电感与微带片之间采用导电型胶粘剂粘结互联。由于导电型胶粘剂长期暴露空气中易产生氧化,粘结处易发生电阻值增大甚至裂缝现象,因此存在互联可靠性降低的问题。通过微点焊技术对漆包线电感进行微点焊互联,改善效果显著,解决了互联可靠性降低的问题。 展开更多
关键词 导电型胶粘剂 电感 微带片 微点焊
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采用孔径耦合微带片的无限相控阵的分析
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作者 D.M.波扎 李国金 《雷达与对抗》 1990年第2期40-50,共11页
本文分析了采用孔径耦合微带片天线的无限阵列;这种阵元非常适合于集成相控阵应用,它与其它阵列结构相比具有若干优点。该解法是采用频谱域力矩法求解,它兼有以往探针馈电的无限阵列解法的特征以及单个孔径耦合微带阵元的互易性分析的... 本文分析了采用孔径耦合微带片天线的无限阵列;这种阵元非常适合于集成相控阵应用,它与其它阵列结构相比具有若干优点。该解法是采用频谱域力矩法求解,它兼有以往探针馈电的无限阵列解法的特征以及单个孔径耦合微带阵元的互易性分析的特征。本文给出了若干阵列有源输入阻抗的数据并作了理论分析。从波导模拟器得出的实验数据证实了这一理论。 展开更多
关键词 天线 微带片 相控阵 孔径 耦合
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低成本Ka波段微带片单脉冲天线
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作者 张鸿祥 张龙元 《贵州航天》 1990年第2期35-38,共4页
关键词 单脉冲 天线 KA波段 微带片 雷达
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顺序馈电在宽频带,园极化微带片阵的应用
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作者 钟声 张忠彭 《贵州航天》 1991年第1期7-16,共10页
关键词 天线 馈电 宽频带 园极化 微带片
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Study of multi-band property of rectangular microstrip patch antenna having different numbers of wide slots 被引量:1
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作者 A.S.Abdallah Y.E.Mohammed 刘元安 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期10-15,共6页
The property of multi-band operation has been studied and investigated analytically through the design of a rectangular patch microstrip antenna having different numbers of wide slots arranged at both the radiating ed... The property of multi-band operation has been studied and investigated analytically through the design of a rectangular patch microstrip antenna having different numbers of wide slots arranged at both the radiating edges. The analyses were carried out using the method of moments simulation software. It is shown that a patch with three slots has a multi-band feature with four resonant frequencies at 1.6, 1.8, 2.65, and 4.83 GHz and adequate values of return loss and gain. It is also shown that a patch with two pairs of wide slots arranged at both the radiating edges has the dual band feature with resonant frequencies at 1.64 and 1.8 GHz and good values of return loss and gain. 展开更多
关键词 microstrip patch antenna multi-band property broadband antenna
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Multi-species particle swarms optimization based on orthogonal learning and its application for optimal design of a butterfly-shaped patch antenna
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作者 孙丽玲 胡静涛 +2 位作者 胡琨元 何茂伟 陈瀚宁 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第8期2048-2062,共15页
A new multi-species particle swarm optimization with a two-level hierarchical topology and the orthogonal learning strategy(OMSPSO) is proposed, which enhances the global search ability of particles and increases thei... A new multi-species particle swarm optimization with a two-level hierarchical topology and the orthogonal learning strategy(OMSPSO) is proposed, which enhances the global search ability of particles and increases their convergence rates. The numerical results on 10 benchmark functions demonstrated the effectiveness of our proposed algorithm. Then, the proposed algorithm is presented to design a butterfly-shaped microstrip patch antenna. Combined with the HFSS solver, a butterfly-shaped patch antenna with a bandwidth of about 40.1% is designed by using the proposed OMSPSO. The return loss of the butterfly-shaped antenna is greater than 10 d B between 4.15 and 6.36 GHz. The antenna can serve simultaneously for the high-speed wireless computer networks(5.15–5.35 GHz) and the RFID systems(5.8 GHz). 展开更多
关键词 particle swarm optimization(PSO) multi-species coevolution orthogonal experimental design butterfly-shaped patch antenna
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Compact Two Shorting Pin Loaded ETMA
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作者 Kamil Yavuz Kapusuz Birkan Dagdeviren Sultan Can 《Computer Technology and Application》 2013年第4期185-189,共5页
In this study ETMA (Equilateral Triangular Microstrip Antennas) are designed to form dual frequency by inserting two shorting pins. Microstrip patch antennas' resonant frequencies with two shorting pins are represe... In this study ETMA (Equilateral Triangular Microstrip Antennas) are designed to form dual frequency by inserting two shorting pins. Microstrip patch antennas' resonant frequencies with two shorting pins are represented in this study by not only considering the theoretical results but also considering the both simulated and experimental results. For each geometry, positions of shorting pins are varied and effects of these variations are analyzed. The presented patch antennas in literature which have the same shape with shorting pin and without shorting pin are compared and results are presented. The methods in literature presented for estimating the resonant frequency depends on analytical methods which are originated from curve fitting. The results of this study will be the basement of the latter studies that predict the resonant frequencies of mentioned antennas before producing the antenna so that the engineers handle the problem by saving the time and estimating the frequency before production. 展开更多
关键词 Shorting pin dual frequency equilateral triangular patch antenna.
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Isolation of 24 novel cDNA fragments from microdissected human chromosome band
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作者 ZHANG MIN L0NG YU +4 位作者 PEI RONG HU AN DINGBI JIA HUI XIA HAN XIANG DENG SHOU YUANZHAO(Institute 0f Genetics, Fudan University, Shanghai 2O0j23,China(State Key La6omtory of Medical Genetics, Hunan Medical Un1versity, Chang8ha J10078, China) 《Cell Research》 SCIE CAS CSCD 1998年第2期135-142,共8页
The strategy of isolating the band-specific expression fragments from a probe pool generated by humanchromosome microdissection was reported. A cliromosome 14q24.3 band-specific single copy DNA pool was constructed ba... The strategy of isolating the band-specific expression fragments from a probe pool generated by humanchromosome microdissection was reported. A cliromosome 14q24.3 band-specific single copy DNA pool was constructed based on this probe pool. Using total DNA of the pool as probe to hybridize the human marrow cDNA library, 68 primary positive clones were selected from 5 ×105 cDNA clones. Among these primary clones, 32 secondary clones were obtained after second-round screening and designed as cFD14-1~32. Finally, 24 band-specific expression fragments were identified from these 32 positive clones by DNA hybridization. Those band-specific clones can hybridize to both 14q24.3 DNA and human genomic DNA but cann’t hybridize to 17q11~12 DNA. Partial sequences of 13 fragments of them were sequenced and identified as novel cDNA sequences , and these sequences were proved to have some homology with known genes in NCBI database. Analysis of expression spectrum of cFD14-1 suggested that the cDNA fragments thus obtained should be used to isolate the genes can not been cloned in 14q24.3region. 展开更多
关键词 Probe pool chromosome 14q24.3 single copy DNA pool expression sequences of genes
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Environmental pressure rather than ongoing hybridization is responsible for an altitudinal cline in the morphologies of two oaks
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作者 Ichiro Tamaki Yae Yamada 《Journal of Plant Ecology》 SCIE CSCD 2020年第4期413-422,共10页
Aims In a contact zone between related taxa,phenotypic variation can result from genetic and/or environmental gradients.This study aimed to clarify the cause of phenotypic variation in leaf morphology of two Quercus c... Aims In a contact zone between related taxa,phenotypic variation can result from genetic and/or environmental gradients.This study aimed to clarify the cause of phenotypic variation in leaf morphology of two Quercus crispula varieties—crispula(QCC)and mongolicoides(QCM)—in their contact zone along an altitudinal gradient.Methods We measured 6 morphological traits of leaves and recorded genotypes of 13 nuclear microsatellite loci for 48 individuals in the contact zone and 24 individuals in each of the reference populations of QCC and QCM.We constructed a model explaining the phenotypic variation(leaf morphology)in relation to environmental(altitude)and genetic(ancestry from the reference population)gradients.Important Findings Both morphological and genetic markers distinguished the two varieties in the reference populations well.We were able to confirm the power of both morphological and genetic markers.Individuals within the contact zone population had intermediate ancestry that was slightly biased to QCM ancestry,and the distribution of their morphologies overlapped with those of the two varieties in the reference populations.The effect of altitude on leaf morphological traits was significant,while that of ancestry was not.Distributions of ancestry and interclass heterozygosity in the contact zone population resembled those in F2 or later generation hybrids.These results indicate that in the contact zone between QCC and QCM,there is no ongoing hybridization,but environmental pressure has created an altitudinal gradient in morphological traits through phenotypic plasticity and/or variation in functional genes. 展开更多
关键词 Quercus crispula Quercus mongolica leaf morphologies microsatellites hybrid zone
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