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小型化波导-微带复合功分网络设计

电子机械工程 2024年第2期40卷 11-14页

作者：石方亮杨双根范宇中国电子科技集团公司第三十八研究所安徽合肥230088

功分网络是有效载荷的重要组成部分,低驻波比、低损耗和轻小型化是航天器功分网络设计的重点。为实现一种新型高效功分结构,文中研制了一种ka频段波导-微带复合功分网络,采用高集成一体化结构设计,集成了24通道的功率输出能力,有效降低... 详细信息

功分网络是有效载荷的重要组成部分,低驻波比、低损耗和轻小型化是航天器功分网络设计的重点。为实现一种新型高效功分结构,文中研制了一种ka频段波导-微带复合功分网络,采用高集成一体化结构设计,集成了24通道的功率输出能力,有效降低了功分网络的体积和重量。实测结果显示,在23.4~24.59 GHz频带范围内,总口驻波比1.3,插入损耗1.6 d B,分口隔离度20 dB,且端口一致性良好,实现了一种轻小化、多通道、低损耗的功分网络设计,在星载毫米波功率合成领域的应用前景广阔。

关键词：波导-微带复合功分网络结构设计

Fe_(25)Co_(25)Pt_(25)B_(25)高熵纳米复相永磁体的组织结构与磁性能

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材料热处理学报 2024年第3期45卷 22-28页

作者：贾雨桐薛钧升李艳辉马殿国张伟大连理工大学材料科学与工程学院三束材料改性教育部重点实验室辽宁大连116024

采用液态急冷法制备了高熵Fe_(25)Co_(25)Pt_(25)B_(25)合金,研究了其热处理前后的组织结构及磁性能。结果表明:Fe_(25)Co_(25)Pt_(25)B_(25)高熵合金具有较高的非晶形成能力,液态急冷合金形成了非晶态结构,表现出软磁特性。Fe_(25)Co_(... 详细信息

采用液态急冷法制备了高熵Fe_(25)Co_(25)Pt_(25)B_(25)合金,研究了其热处理前后的组织结构及磁性能。结果表明:Fe_(25)Co_(25)Pt_(25)B_(25)高熵合金具有较高的非晶形成能力,液态急冷合金形成了非晶态结构,表现出软磁特性。Fe_(25)Co_(25)Pt_(25)B_(25)高熵非晶合金热处理结晶化过程为:非晶相→非晶相+fcc-(Fe,Co)Pt相→非晶相+fcc-(Fe,Co)Pt+L1_(0)-(Fe,Co)Pt+(Fe,Co)2B相→非晶相+L1_(0)-(Fe,Co)Pt+(Fe,Co)2B相→L1_(0)-(Fe,Co)Pt+(Fe,Co)2B相。经843 K热处理900 s后,Fe_(25)Co_(25)Pt_(25)B_(25)合金形成了由有序面心四方结构的永磁L1_(0)-(Fe,Co)Pt相和软磁(Fe,Co)2B相组成的纳米复相组织,平均晶粒尺寸约为19 nm,表现出纳米复相永磁体特性,其矫顽力(iHc)、剩磁(Br)、剩磁比(Mr/Ms)和磁能积((BH)_(max))分别为946.8 ka·m^(-1)、0.46 T、0.78和40.9 kJ·m^(-3)。其超大iHc主要是高熵化使L10相的c/a增大导致磁晶各向异性增大的结果。

关键词： FeCoPtB高熵合金纳米复相永磁体非晶态合金结晶化矫顽力

Results of the influenza virus surveillance in wild birds in Western part of Mongolia

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Asian Pacific Journal of Tropical Medicine 2010年第2期3卷 90-93页

作者： Marchenko V yu Alekseev A yu Tserennorov D yurlov AK Susloparov IM Sharshov ka Ilyinykh FA Zolotykh SI Abmed D Otgonbaatar D Shestopalov AM Federal State Research Institution State Research Center of Virology and Biotechnology VectorKoltsovoNovosibirsk RegionRussia National Centre for Diseases with Natural Foci UlaanbaatarMongolia Institute of Systematic and Ecology of Animals Siberian BranchRussian Academy of ScienceNovosibirskRussia National Centre for Infectious Diseases UlaanbaatarMongolia

Objective:To present results of virological study of wild birds inhabiting Western Mongolia. Methods:Over a period of 2003-2008,we isolated 13 influenza A viruses:H1N1,H3N6, H13N8 and H4N6 *** did not isolate any H5N1 subtype,that still cause epizooty in wild birds and ***:We revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given *** viruses were isolated from birds of 6 orders;among them there are species preferring water and semi-aquatic biotopes,one species preferring dry plain region,and also one species which can inhabit both dry and water ***:Representatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation,highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it’s necessary to continue permanent influenza virus surveillance in wild birds’ populations.

关键词： Influenza A virus Mongolia Wild birds

Coercivity enhancement of hot-deformed Nd-Fe-B magnets with Pr-Cu alloy addition

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Rare Metals 2023年第4期42卷 1403-1407页

作者： Jun-Ming Wang Zhao-Hui Guo Zheng Jing Xiao Du Neng-Jun yu Meng-yu Li Ming-Gang Zhu Wei Li Division of Functional Materials Central Iron&Steel Research InstituteBeijing100081China

Effects of low-melting Pr-Cu alloy addition on the microstructure and magnetic properties of the hot-deformation Nd-Fe-B magnets were investigated.A small amount of Pr-Cu addition enhances the coercivity of the hot-deformation Nd-Fe-B magnets *** coercivity of the hotdeformation Nd-Fe-B magnets with 4.0 wt%Pr_(85)Cu_(15)addition increases to 1271 ka·m^(-1),75.69%higher than that of Pr-Cu-free magnet(723 ka·m^(-1)),and then decreases with5 wt%Pr_(85)Cu_(15)*** is observed that there a uniform RE-rich phase is formed wrapping the Nd2Fe14B main phase in the sample with 4.0%Pr_(85)Cu_(15)addition by scanning electron microscopy(SEM),which promotes the *** angular dependence of coercivity for the hot-deformation Nd-Fe-B magnets indicates that the coercivity mechanism is nucleation combined with domain wall *** domain wall pinning is weakened,while the nucleation is enhanced after Pr-Cu ***,intrinsic coercivity,and maximum magnetic energy product of the original Nd-Fe-B magnet are 1.45 T,723 ka·m^(-1),and 419.8 kJ·m^(-3),respectively,and those of the sample with 4.0%Pr_(85)Cu_(15)alloy addition are 1.30 T,1271 ka·m^(-1),and 330.0 kJ·m^(-3),respectively.

关键词： Nd-Fe-B Low-melting alloy Hot-deformation Microstructure Coercivity mechanism

Uncovering the prominent role of satellite cells in paravertebral muscle development and aging by single-nucleus RNA sequencing

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Genes & Diseases 2023年第6期10卷 2597-2613页

作者： Xin Qiu Hao-yu Wang Zhen-yu Yang Li-Ming Sun Shu-Nan Liu Chui-Qin Fan Feng Zhu Department of Spinal Surgery The University of Hong Kong-Shenzhen HospitalShenzhenGuangdong 518000China Department of Orthopedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SAR 999077China College of Life Sciences University of Chinese Academy of SciencesBeijing 100000China Lars Bolund Institute of Regenerative Medicine Qingdao-Europe Advanced Institute for Life SciencesBGI-QingdaoQingdaoShandong 266000China China Medical University ShenyangLiaoning 110000China Department of Plastic and Reconstructive Surgery Xijing HospitalForth Military Medical UniversityXi'anShaanxi 710000China

To uncover the role of satellite cells(SCs)in paravertebral muscle development and aging,we constructed a single-nucleus transcriptomic atlas of mouse paravertebral muscle across seven timepoints spanning the embryo(day 16.5)to old(month 24)*** cell types,including SCs,fast muscle cells,and slow muscle cells,were *** energy metabolism-related gene set,TCA CYCLE IN SENESCENCE,was enriched in ***-two skeletal muscle disease-related genes were highly expressed in SCs and exhibited similar expression *** them,Pdha1 was the core gene in the TCA CYCLE IN SENESCENCE;Pgam2,Sod1,and Suclg1 are transcription factors closely associated with skeletal muscle energy *** factor enrichment analysis of the 42 genes revealed that Myod1 and Mef2a were also highly expressed in SCs,which regulated Pdha1 expression and were associated with skeletal muscle *** findings hint that energy metabolism may be pivotal in SCs development and *** ligand-receptor pairs of extracellular matrix(ECM)-receptor interactions,Lamc1-Dag1,Lama2-Dag1,and Hspg2-Dag1,may play a vital role in SCs interactions with slow/fast muscle cells and SCs ***,we built the first database of a skeletal muscle single-cell transcriptome,the Musculoskeletal Cell Atlas(http://***),which lists 630,040 skeletal muscle cells and provides interactive visualization,a useful resource for revealing skeletal muscle cellular heterogeneity during development and *** study could provide new targets and ideas for developing drugs to inhibit skeletal muscle aging and treat skeletal muscle diseases.

关键词： Niche Paraspinal muscle Satellite cells Senescence Single-nucleus RNA sequencing

Uncovering novel human gut virome using ultra-deep metagenomic sequencing

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Chinese Medical Journal 2022年第20期135卷 2395-2397页

作者： Harry Cheuk Hay Lau Jun yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health Sciencesthe Chinese University of Hong KongHong Kong SARChina

Human gastrointestinal tract harbors trillions of commensal microbes including bacteria,viruses,and fungi to form an ecological community,commonly known as the gut *** the second most dominant taxonomic kingdom in the gut(5.8%of total microbiome DNA),enteric viruses are increasingly acknowledged for their roles in shaping the overall composition of the gut microbiome and maintaining human health.[1,2]Recent advancements in metagenomic sequencing have brought breakthrough in deciphering the features and functions of the gut virome.

关键词： breakthrough harbor gut

Coercivity enhancement of hot-deformed NdFeB permanent magnets with AlCuZn eutectic alloy grain boundary diffusion

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Rare Metals 2022年第1期41卷 226-231页

作者： Ye-Qi yu Kuo-She Li Hai-Jun Peng Xin-yuan Bai Ning-Tao Quan kai-Wen Wu Yang Luo Dun-Bo yu National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing 100088China GRIREM Advanced Materials Co.Ltd.Beijing 100088China

It is approved that grain boundary diffusion is an effective method to increase the coercivity of hot-deformed NdFeB *** this paper,a new rare earth-free grain boundary diffusion source of hot-deformed magnet was *** powders blended with commercial NdFeB powders were hot-compacted to obtain fully dense magnets,hot-deformed into anisotropic magnets and finally annealed to gain better ***,the influences of annealing temperature and time on the magnetic properties of the specimens were studied and the optimal parameters of 600℃ and 60 min were ***,by changing the proportions of AlCuZn grain boundary diffusion,the coercivity,remanence and maximum energy product of the hot-deformed NdFeB magnets were *** result showed that with 1.0 wt%AlCuZn grain boundary diffusion and annealing at 600℃ for 60 min,the coercivity rose from 828 to 987 ka·m^(-1) without deteriorating the *** analysis confirmed that AlCuZn diffused into the intergranular boundaries and the magnet diffused with AlCuZn possessed finer grains than that of without AlCuZn grain boundary diffusion.

关键词： AlCuZn Grain boundary diffusion Hotdeformed Coercivity enhancement

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黑斑息肉综合征肿瘤相关基因初步筛选

临床军医杂志 2010年第5期38卷 740-742页

作者：戴益琛林志翔姜元芹陈章兴谢军培曾伟傅育卡解放军第174医院消化内科福建厦门361003

目的探索黑斑息肉综合征(PJS)肿瘤特异性相关基因。方法用基因芯片技术研究PJS息肉的基因表达谱,筛选出差异表达基因,建立和研究PJS与肿瘤相关的差异基因表达。结果大肠PJS息肉411个基因差异表达,其中上调的有197个基因,下调表达的有... 详细信息

目的探索黑斑息肉综合征(PJS)肿瘤特异性相关基因。方法用基因芯片技术研究PJS息肉的基因表达谱,筛选出差异表达基因,建立和研究PJS与肿瘤相关的差异基因表达。结果大肠PJS息肉411个基因差异表达,其中上调的有197个基因,下调表达的有214个。在基因芯片总共144个癌基因与抑癌基因中,共有13个基因发生差异表达,其中PTTG1、LCN2、LATS2、MADH4、RALB、HRAS、APC、USP4为高表达;IGF2R、ELF3、EGFR、MCAM、ERBB2为低表达。结论这些肿瘤相关基因的差异表达,可能与PJS容易发生恶性肿瘤的潜能有关。

关键词：黑斑息肉综合肿瘤相关基因初步筛选 related genes 基因差异表达基因芯片技术差异基因表达差异表达基因抑癌基因肿瘤特异性基因表达谱下调表达恶性肿瘤 PJS息肉高表达低表达 ERBB2 潜能结果

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马莲河下游产水量时空演变特征

干旱区研究 2024年第5期41卷 776-787页

作者：高雅玉宋玉赵廷红高金芳何文博李泽霞兰州理工大学能源与动力工程学院甘肃兰州730050 甘肃省水土保持科学研究所甘肃兰州730020

马莲河下游流域是我国陇东典型的黄土高原沟壑区,在气候和土地利用变化背景下研究其产水量的时空特征和变化响应,对区域生态系统可持续发展具有重要意义。基于InVEST(Integrated Valuation of Ecosystem Services and Trade-offs)模型... 详细信息

马莲河下游流域是我国陇东典型的黄土高原沟壑区,在气候和土地利用变化背景下研究其产水量的时空特征和变化响应,对区域生态系统可持续发展具有重要意义。基于InVEST(Integrated Valuation of Ecosystem Services and Trade-offs)模型定量评估1990年、2000年、2010年和2020年4个时期马莲河下游流域产水量的时空格局和变化,运用地理探测器分析影响因子对产水功能空间分异的影响程度。结果表明:(1)1990—2020年,马莲河下游流域总产水量整体呈现先减后增再减的变化趋势,2020年总产水量相比1990年减少了5.9×10^(7) m^(3),减少率为25.43%。不同时期产水量在空间上呈现南部和边缘地带高、北部和中心地带低的分布特征。(2)不同土地利用类型产水能力大小排序依次为:城镇用地>未利用地>耕地>低覆盖度草地>高覆盖度草地>灌木林>有林地>水域。(3)产水量与降水量呈现明显的正相关,与实际蒸散发量和海拔之间存在负相关。降水和实际蒸散发是决定产水量空间分布和变化的主导因素,q值分别为0.616~0.735和0.517~0.653。研究成果可为陇东黄土高原沟壑区水土资源开发、利用和管理提供科学支撑。

关键词： InVEST模型产水量时空演变马莲河下游

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