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Withdrawal Weighting Image-Impedance Connected SAW Filters with Al-Mo Alloy Electrodes 被引量:1
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作者 Dongmei Li xubo wang Feng Pan 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期623-624,共2页
To obtain high reliability of surface acoustic wave(SAW)devices,Mo was added to Al electrodes on 128°Y-X LiNbO_3 substrates by a d.c.magnetron sputtering deposition.Influence of Mo additive on the mechanical prop... To obtain high reliability of surface acoustic wave(SAW)devices,Mo was added to Al electrodes on 128°Y-X LiNbO_3 substrates by a d.c.magnetron sputtering deposition.Influence of Mo additive on the mechanical properties of Al films was investigated.It was found that the Al-Mo alloy films displayed a superior adhesion to substrates.With the Al-Mo alloy films,a 1.65 GHz-range image-impedance connected SAW filter was designed and fabricated.In this structure of SAW filter, for satisfying stopband requirements a dual-track structure was applied.Withdrawal weighting of interdigital transducers(IDT) was used to adjust the bandwidth of SAW filter. 展开更多
关键词 Al-Mo films ADHESION surface acoustic wave
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Development of polymorphic SSR markers and their applicability in genetic diversity evaluation in Euptelea pleiosperma
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作者 XIAOJUN ZHOU XIAOYU LU xubo wang 《BIOCELL》 SCIE 2022年第11期2489-2495,共7页
Euptelea pleiosperma is a characteristic species of East Asian flora with both ornamental and scientific values.Based on the reduced-representation sequencing(RRS)technology of RAD-Seq,this study conducted high-throug... Euptelea pleiosperma is a characteristic species of East Asian flora with both ornamental and scientific values.Based on the reduced-representation sequencing(RRS)technology of RAD-Seq,this study conducted high-throughput Illumina paired-end sequencing to find SSR marker information in the genome of E.pleiosperma,and to screen and verify polymorphism of SSR markers.We obtained 5.5G of high-quality data using RAD-Seq.The total number of contigs of the RAD tags was 299,376,with the maximum contig length of 2,062 bp and the average length of 445 bp.From these sequences,we identified 20,718 SSR loci,with a distribution density of one SSR per 6.45 kb(1/6.45 kb).Among all SSRs,dinucleotides(52.00%)were the most detected SSRs,followed by mononucleotides(21.63%).AG/CT was the dominant motif in the SSR loci,accounting for 34.8%.Primers were successfully designed for 14,593 loci,and 100 pairs of these primers were randomly selected for chemical synthesis and validated by SSR-PCR amplification in 20 individuals of E.pleiosperma.Seventy-nine primers were able to amplify the target bands.Cervus 3.0 software was used to analyze the selected 20 SSR loci with good polymorphism.For the 20 SSR markers,the number of alleles ranged from 4 to 9,and the observed heterozygosity and expected heterozygosity were from 0.35 to 0.75 and 0.541 to 0.875,respectively.The information content of polymorphic loci ranged from 0.463 to 0.848,with an average value of 0.638.Among them,there were 18 highly polymorphic loci,and 20 SSR loci did not deviate from the Hardy-Weinberg equilibrium.Furthermore,the 20 pairs of SSR primers were used to conduct PCoA analysis based on Nei’s genetic distance of 51 individuals from three populations.The results showed that these SSR markers could distinguish genetic differences based on different geographical locations. 展开更多
关键词 Cluster analysis E.pleiosperma RAD-Seq Rare species SSR markers
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IT相关专业离散数学教学研究(英文)
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作者 xubo wang Yingfeng wang 《计算机教育》 2016年第4期16-20,共5页
离散数学作为一个和连续数学不同的领域一直在IT中扮演重要角色。离散数学的教学被认为是IT教学中不可分割的部分。然而,由于各学校情况不同,面向IT学生的离散数学教学仍存在一些挑战。文章介绍一所美国大学针对IT专业本科生的不同背景... 离散数学作为一个和连续数学不同的领域一直在IT中扮演重要角色。离散数学的教学被认为是IT教学中不可分割的部分。然而,由于各学校情况不同,面向IT学生的离散数学教学仍存在一些挑战。文章介绍一所美国大学针对IT专业本科生的不同背景和需求进行教学设计以满足教学目标,期望这些经验能对其他学校相关课程的设计有所帮助。 展开更多
关键词 离散数学 教学 IT
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云南哀牢山国家级自然保护区东坡垂直带蚂蚁物种多样性
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作者 赵梦乔 陈友 +5 位作者 徐正会 王戌勃 赵忠良 徐文川 何宗辉 王文华 《生物多样性》 CAS CSCD 北大核心 2023年第11期119-130,共12页
哀牢山地处青藏高原、横断山地和云贵高原三大自然地理区域的结合部,在这样一个特殊的地理气候区域内栖息着怎样的蚂蚁群落?不同海拔高度引起的气候条件差异导致蚂蚁群落结构和多样性产生了怎样的差异?为了揭示这一科学问题,本文采用样... 哀牢山地处青藏高原、横断山地和云贵高原三大自然地理区域的结合部,在这样一个特殊的地理气候区域内栖息着怎样的蚂蚁群落?不同海拔高度引起的气候条件差异导致蚂蚁群落结构和多样性产生了怎样的差异?为了揭示这一科学问题,本文采用样带法、样地调查法和多样性指标法研究了哀牢山国家级自然保护区东坡垂直带的蚂蚁物种多样性。在哀牢山国家级自然保护区东坡垂直带记录蚂蚁7亚科47属150种,喜马毛蚁(Lasiushimalayanus)是蚂蚁群落的优势种,同时发现常见种2个,较常见种20个,较稀有种55个,稀有种72个,稀有种占了物种总数的48.00%。东坡4个垂直带蚂蚁群落的Shannon-Wiener多样性指数顺序为:中南段>北段>中北段>南段。相关性分析显示蚂蚁的物种数和多样性指数与海拔存在显著负相关性,物种数、个体密度和多样性指数与乔木郁闭度存在显著负相关性。蚂蚁群落在海拔梯度间表现出高度的不相似性和强烈的更替模式,不同垂直带间的蚂蚁群落同样表现出高度的不相似性和强烈的更替格局。哀牢山自然保护区东坡各垂直带蚂蚁物种数、个体密度、多样性指数总体上随海拔升高而降低,主要受海拔和气温因素制约;这些指标普遍出现多域效应现象,有时出现中域效应现象,说明不同海拔高度上栖息着适应了不同气候类型的物种聚集群,同时受到人类干扰和干热河谷气候的影响。哀牢山自然保护区东坡蚂蚁物种丰富度低于西坡,主要受湿度因素影响。从相似性系数看,栖息于保护区不同生境的蚂蚁群落间分化明显,具有不同的生态功能和保护价值。 展开更多
关键词 蚁科 群落 生物多样性 自然保护区 垂直带
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Characterization of the first mitochondrial genome of Aclerdidae (Hemiptera: Coccoidea) with a novel gene arrangement
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作者 Qingsong Zhou Mei Xiong +2 位作者 Arong Luo xubo wang San’an Wu 《Zoological Systematics》 CSCD 2022年第4期293-304,共12页
Scale insects comprise a diverse group of insects within superfamily Coccoidea in the suborder Sternorrhyncha,many of them are important pests of economic crops.The advent in next-generation sequencing(NGS)technologie... Scale insects comprise a diverse group of insects within superfamily Coccoidea in the suborder Sternorrhyncha,many of them are important pests of economic crops.The advent in next-generation sequencing(NGS)technologies has revolutionized conventional phylogenomic researches,causing a rapid accumulation of sequenced insect mitochondrial genomes.However,there have been few studies on the mitochondrial genome of diverse scale insect groups.By using NGS methods,the complete mitochondrial genome of Nipponaclerda biwakoensis was obtained in this study,representing the first mtDNA of the family Aclerdidae.The whole mitochondrial genome is 16,654 bp in length with an A+T content of 81.3%,including 13 protein-coding genes(PCGs),2 ribosomal RNAs,17 transfer RNAs and a control region.All PCGs begin with typical ATN codons and use standard TAA as their termination codons,except nad1 gene stopping with TAG.Meanwhile,this mitochondrial genome shows a unique gene rearrangement with a long fragment(trnP-trnC-trnI-nad2-trnY-trnT)insertion in the conserved region nad6-cob,which is novel to Hemiptera,even Insecta.The phylogeny reconstruction of Sternorrhyncha based on 13 PCGs and 2 rRNAs under Bayesian Inference method support a robust topology that Aleyrodoidea is the earliest branch of Sternorrhyncha,with Psylloidea as the sister group of the(Aphidoidea+Coccoidea)clade. 展开更多
关键词 Mitochondrial genome scale insects gene arrangement PHYLOGENY Nipponaclerda biwakoensis
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Imidazole-Linked Fully Conjugated Covalent Organic Framework for High-Performance Sodium-Ion Battery
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作者 Lu Liu Yu Gong +10 位作者 Yifan Tong Hao Tian xubo wang Yiming Hu Shaofeng Huang Weiwei Huang Sandeep Sharma Jingnan Cui Yinghua Jin Weitao Gong Wei Zhang 《CCS Chemistry》 2024年第5期1255-1263,共9页
Covalent organic frameworks(COFs)have garnered increasing attention as promising electrode materials for sodium-ion batteries(SIBs)due to their ordered backbones,uniform pore sizes,and high surface areas.However,they ... Covalent organic frameworks(COFs)have garnered increasing attention as promising electrode materials for sodium-ion batteries(SIBs)due to their ordered backbones,uniform pore sizes,and high surface areas.However,they also face challenges,including low capacity,unsatisfactory rate performance,and limited cycling stability,which pose the primary obstacles to their practical use.Herein,a pyrenoimidazole-based COF,denoted as PyIm-COF,has been synthesized as a novel electrode material for highperformance SIBs using an efficient synthetic strategy.With extended fully conjugated backbones and readily accessible redox-active sites,PyIm-COF demonstrates remarkable high-rate performance,delivering around 250 m Ah g^(−1)and excellent cycling stability,retaining 97.2%of its capacity even after 2500 cycles at 5 A g^(−1),which is higher than that of most previously reported COF-based SIBs.This work provides valuable insights into the development of nitrogen-rich conjugated COF electrode materials for rechargeable SIBs. 展开更多
关键词 pyrenoimidazole fully conjugated backbones covalent organic framework electrode material sodium-ion battery
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