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Science China(Technological Sciences) 2020年第4期63卷 655-667页

作者： wen zhe-xi LV Yi-Gao LI Qing School of Energy Science and EngineeringCentral South UniversityChangsha 410083China

Printed circuit heat exchangers(PCHEs)are promising candidates for recuperators in supercritical CO2 Brayton cycles.A comparative study is given in this paper on the flow and heat transfer characteristics of PCHEs with sinusoidal and zigzag *** mass flow rates of 0.6–1.8 kg/h and the bend angles of 15°–30°,the thermal-hydraulic performance of the PCHEs is *** show that the sinusoidal channel is superior to the zigzag channel in its comprehensive *** bend angles result in greater reductions in pressure drop if sinusoidal channels are used instead of zigzag channels and a maximum of 48.4%reduction can be obtained in the considered working ***,the inlet sections should be carefully optimized since these sections account for up to 31%and 17%of the total pressure drop in the sinusoidal and zigzag channels,*** corner shape of the zigzag channel can be specially designed to further reduce the pressure *** nonuniform density and heat flux distributions in both channels are found to be related to the periodic changes of flow directions and the centrifugal forces should not be ignored when optimizing the sinusoidal and zigzag channels.

关键词： printed circuit heat exchanger supercritical CO2 thermal-hydraulic performance sinusoidal channel numerical simulation

Correcting the Contamination of Second-order Spectra:Improving HαMeasurements in Reverberation Mapping Campaigns

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Research in Astronomy and Astrophysics 2023年第12期23卷 242-251页

作者： wen-zhe xi Kai-xing Lu Hai-Cheng Feng Sha-Sha Li Jin-Ming Bai Rui-Lei Zhou Hong-Tao Liu Jian-Guo Wang Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China CAS Key Laboratory of FAST National FASTNational Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

Long-term spectroscopic monitoring campaigns on active galactic nuclei(AGNs)provide a wealth of information about its interior structure and ***,a number of the observations suffer from the contamination of second-order spectra(SOS)which will introduce some undesirable uncertainties at the red side of the *** this paper,we test the effect of SOS and propose a method to correct it in the time domain spectroscopic data using the simultaneously observed comparison *** on the reverberation mapping(RM)data of NGC 5548 in2019,one of the most intensively monitored AGNs by the Lijiang 2.4 m telescope,we find that the scientific object,comparison star,and spectrophotometric standard star can jointly introduce up to~30%SOS for Grism *** irregular but smooth SOS significantly affects the flux density and profile of the emission line,while having little effect on the light *** applying our method to each spectrum,we find that the SOS can be corrected *** deviation between corrected and intrinsic spectra is~2%,and the impact of SOS on time lag is very *** method makes it possible to obtain the HαRM measurements from archival data provided that the spectral shape of the AGN under investigation does not have a large change.

关键词： techniques spectroscopic-methods data analysis-galaxies individual(NGC 5548)-(galaxies:)quasars emission lines

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration Research 2025年第7期20卷 2068-2083页

作者： Jing Yao Yuan Li xi Liu wenping Liang Yu Li Liyong Wu zhe Wang Weihong Song The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang Laboratory(zhejiang Laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

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阵列空气射流传热均匀性问题的数值研究

工程热物理学报 2016年第11期37卷 2378-2384页

作者：马朝严超曹学伟文哲希何雅玲西安交通大学能源与动力工程学院热流科学与工程教育部重点实验室西安710049 北京机电工程研究所北京100074

针对用于飞行器地面降温模拟试验的喷嘴阵列空气射流的传热均匀性问题,开展了数值模拟研究,用以指导相关降温试验装置的设计和试验方案的制定。首先,对降温试验装置建立了相关模型,通过对比发现SST k-ω湍流模型适用于阵列空气射流冷却... 详细信息

针对用于飞行器地面降温模拟试验的喷嘴阵列空气射流的传热均匀性问题,开展了数值模拟研究,用以指导相关降温试验装置的设计和试验方案的制定。首先,对降温试验装置建立了相关模型,通过对比发现SST k-ω湍流模型适用于阵列空气射流冷却模拟;进而分别研究了喷嘴数量、喷嘴高度等因素对阵列空气射流传热均匀性的影响规律,分析了其中的原因,并通过正交实验获得了研究范围内传热均匀性最优的参数匹配方案,数值计算出相应的表面对流传热系数h的变异系数为0.201;最后,研究了空气横流对阵列空气射流传热均匀性的影响。发现在最优结构参数下,通过添加挡板将最小横向流动形式改为中等横向流动形式后,试件表面的对流换热系数h变异系数减小了39.7%,试件局部表面传热均匀性得到了大幅的提高。

关键词：地面快速降温模拟阵列空气射流传热均匀性数值模拟正交实验

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鸡对传染性法氏囊病病毒强毒株的易感性试验

中国兽药杂志 2000年第4期34卷 5-8页

作者：刘纪存文希喆中国兽药监察所北京100081

无传染性法氏囊病病毒 ( IBDV)母源抗体不同日龄的鸡 ,经人工感染强毒 IBDV,按法氏囊肉眼病变判断 ,3周龄的鸡不易感 ,而 4周龄～ 1 0周龄的鸡都易感 ,不管 SPF鸡或是普通鸡。鸡对强毒 IBDV的易感性。

关键词：鸡传染性法氏囊病病毒易感性弱毒株

Pronounced impact of size and shape effects on creep rupture life of a K439B superalloy combustion chamber casting simulator

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China Foundry 2025年

作者： wen-tong Liu Yi-dong Wu Lei Gao Jing-yang Chen Cheng-bo xiao xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

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银发经济中备老人群消费特征与发展趋势研究

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 48-58,F0002页

作者：彭希哲陈倩复旦大学老龄研究院上海200433

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较... 详细信息

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较高、消费观念开放包容,互联网普及程度较高、消费个性化、注重悦己等群体特征,具有较强的消费能力和消费意愿,备老人群的消费将为银发经济带来巨大的增量空间。深入理解并满足备老人群的消费需求,对推动供需在更高水平实现良性循环、促进银发经济高质量发展具有重要意义。

关键词：银发经济备老经济高质量发展良性循环消费特征

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本质与价值:数字时代广告本体的再认识

武汉大学学报（哲学社会科学版） 2025年第1期78卷 125-132页

作者：姚曦任文姣武汉大学新闻与传播学院湖北武汉430072 武汉大学媒体发展研究中心

用传播的方式促进从生产到消费转换的行为皆为存在意义上的广告,广告的本体是本质与价值的统一。本体的坚守要建立开放的认识观,在不变的广告本质中解释变化着的广告形态,而非用未触及本体的不确定认识窄化新的广告事实。彰显广告价值... 详细信息

用传播的方式促进从生产到消费转换的行为皆为存在意义上的广告,广告的本体是本质与价值的统一。本体的坚守要建立开放的认识观,在不变的广告本质中解释变化着的广告形态,而非用未触及本体的不确定认识窄化新的广告事实。彰显广告价值需深耕数字广告实践,用创意提升广告的社会吸引力,建构多主体参与的沟通网络。彰显广告价值还需要在理论层面,以本体观为支点,立足于本土广告实践,重新组织数字广告研究范畴,使用大数据技术与混合研究法探究新问题,为广告学知识体系的建构提供框架与方向。

关键词：广告广告本质广告价值广告本体

维普期刊数据库博看期刊

An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 29-38页

作者： Tai Liu zhe Wang Mengxi Shi Willie Soon ShiCan Qiu Department of Geophysics College of the Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China Center for Environmental Research and Earth Sciences(CERES) SalemMA 01970USA Institute of Earth Physics and Space Science(ELKH EPSS) 9400SopronHungary

The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler *** this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian *** Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data *** results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward *** variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual *** zonal momentum flux of GW changes little with height,showing weak annual *** meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is *** both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite *** observational evidence is consistent with the filtering *** horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at *** power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance *** PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km.

关键词： meteor radar wind field gravity wave Lomb−Scargle method

关于4-(2′-噻唑偶氮)间苯二酚用作铌分析试剂的研究

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化学学报 1981年第S1期 136-140页

作者：俞汝勤文哲熙斐初珍湖南大学化工系

用分光光度法研究了铌与4-(2′-噻唑偶氮)间苯二酚的络合反应。采用不同方法测定了1:1络合物的组成及表观稳定常数值。在10～25℃测得的反应速度常数值K符合公式InK=30.19-15250/RT。电泳及萃取实验证明有色化合物系以阴离子状态存在于... 详细信息

用分光光度法研究了铌与4-(2′-噻唑偶氮)间苯二酚的络合反应。采用不同方法测定了1:1络合物的组成及表观稳定常数值。在10～25℃测得的反应速度常数值K符合公式InK=30.19-15250/RT。电泳及萃取实验证明有色化合物系以阴离子状态存在于溶液中。讨论了有关分析方法及其应用。

关键词：络合物组成间苯二酚雷琐酚苯酚缓冲溶液等吸收点偶氮络合比等摩尔连续变化法平衡移动法分析试剂噻唑氮杂环化合物