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High Spatial Resolution X-Ray Spectroscopy of Cas A with Chandra

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Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 439-450页

作者： xue-juan yang Fang-Jun Lu Li Chen Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Astronomy Beijing Normal University Beijing 100875 China

We present high spatial resolution X-ray spectroscopy of the supernova remnant Cassiopeia A with the Chandra observations. The X-ray emitting region of this remnant was divided into 38 × 34 pixels of 10″× 10″ each. Spectra of 960 pixels were created and fitted with an absorbed two component non-equilibrium ionization model. From the results of the spectral analysis we obtained maps of absorbing column density, temperatures, ionization ages, and the abundances of Ne, Mg, Si, S, Ca and Fe. The Si, S and possibly Ca abundance maps show obvious jet structures, while Fe does not follow the jet but seems to be distributed perpendicular to it. The abundances of Si, S and Ca show tight correlations between one another over a range of about two dex. This suggests that they are ejecta from explosive O- burning and incomplete Si-burning. Meanwhile, the Ne abundance is well correlated with that of Mg, indicating them to be the ashes of explosive C/Ne burning. The Fe abundance is positively correlated with that of Si when the latter is lower than 3 times the solar value, and is negatively correlated when higher. We suggest that such a two phase correlation is due to the different ways in which Fe was synthesized.

关键词： ISM supernova remnants -ISM individual Cassiopeia A

Unusual infrared emission toward Sgr B2: possible planar C24

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Research in Astronomy and Astrophysics 2019年第10期19卷 35-42页

作者： Xiu-Hui Chen Fu-Yuan Xiang xue-juan yang Aigen Li Department of Physics Xiangtan University Xiangtan 411105 China Department of Physics and Astronomy University of Missouri Columbia MO 65211 USA

Interstellar graphene could be present in the interstellar medium(ISM), resulting from the photochemical processing of polycyclic aromatic hydrocarbon(PAH) molecules and/or collisional fragmentation of graphitic particles. Indeed, by comparing the observed ultraviolet(UV) extinction and infrared(IR) emission of the diffuse ISM with that predicted for graphene, as much as ~ 2% of total interstellar carbon could be locked up in graphene without violating the observational constraints. While the possible detection of planar C24, a small piece of a graphene sheet, has been reported towards several Galactic and extragalactic planetary nebulae, graphene has not yet been detected in interstellar environments. In this work, we search for the characteristic IR features of C24 at ~ 6.6, 9.8 and 20 μm toward Sgr B2, a high-mass star formation region, and find a candidate target toward R.A.(J2000)= 267.05855?and Decl.(J2000)=-28.01479?in Sgr B2 whose Spitzer/IRS spectra exhibit three bands peaking at ~ 6.637, 9.853 and 20.050 μm which appear to be coincident with those of C24. Possible features of C60 are also seen in this region. The candidate region is a warm dust environment heated by massive stars or star clusters, associated with a WISE spot(a tracer of star formation activity), close to the HII region candidate IRAS 17450–2759, and is surrounded by seven young stellar object candidates within ~ 5′, suggesting that the creation and/or excitation of C24 could be related to star formation activities.

关键词： line identification-ISM lines and bands-ISM molecules

High spatial resolution spectroscopy of G292.0+1.8 with Chandra

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Research in Astronomy and Astrophysics 2014年第10期14卷 1279-1288页

作者： xue-juan yang Xiao-Qin Liu Shun-Yu Li Fang-Jun Lu Faculty of Materials Optoelectronics and PhysicsXiangtan University Particle Astrophysics Center Institute of High Energy PhysicsChinese Academy of Sciences

We present high spatial resolution X-ray spectroscopy of supernova rem- nant G292.0＋1.8 made with Chandra observations. The X-ray emitting region of this remnant was divided into 25 × 25 pixels with a scale of 20＂ × 20＂ each. Spectra of 328 pixels were created and fitted with an absorbed one component non-equilibrium ionization model. With the spectral analysis results, we obtained maps of absorbing column density, temperature, ionization age and abundances for O, Ne, Mg, Si, S and Fe. The abundances of O, Ne and Mg show tight correlations between each other in the range of about two orders of magnitude, suggesting that they are all from explo- sive C/Ne burning. Meanwhile, the abundances of Si and S are also well correlated, indicating that they are the ashes of explosive O-burning or incomplete Si-burning. The Fe emission lines are not prominent in the whole remnant, and their abundance is significantly reduced, indicating that the reverse shock may not have propagated to the Fe-rich ejecta. Based on relative abundances of O, Ne, Mg, Si and Fe to Si, we suggest a progenitor mass of 25 - 30 M⊙ for this remnant.

关键词： ISM supernova remnants -- ISM individual G292.0+1.8

XMM-Newton observation of the eclipsing binary Algol

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Research in Astronomy and Astrophysics 2011年第4期11卷 457-470页

作者： xue-juan yang Fang-Jun Lu Bemd Aschenbach Li Chen Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105China Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Max-Planck-Institut fur Extraterrestrische Physik 85741 Garching Germany Department of Astronomy Beijing Normal University Beijing 100875 China

We present an XMM-Newton observation of the eclipsing binary Algol which contains an X-ray dark B8V primary and an X-ray bright K2IV secondary. The observation covered the optical secondary eclipse and captured an X-ray flare that was eclipsed by the B star. The XMM-Newton European Photon Imaging Camera and Reflection Grating Spectrometer spectra of Algol in its quiescent state are described by a two-temperature plasma model. The cool component has a temperature around 6.4× 106 K while that of the hot component ranges from 2 to 4.0× 107 K. Coronal abundances of C, N, O, Ne, Mg, Si and Fe were obtained for each component for both the quiescent and the flare phases, generally with upper limits for S and Ar, and upper limits for C, N, and O from the hot component. F-tests show that the abundances do not need to be different between the cool and the hot component and between the quiescent and the flare phase with the exception of Fe. Although the Fe abundance of the cool component remains constant at -0.14, the hot component shows an Fe abundance of -0.28, which increases to -0.44 during the flare. This increase is expected from the chromospheric evaporation model. The absorbing column density NH of the quiescent emission is 2.5 - 1020 cm-2, while that of the flare-only emission is significantly lower and consistent with the column density of the interstellar medium. This observation substantiates earlier suggestions of the presence of X-ray absorbing material in the Algol system.

关键词： stars abundance -- star binaries eclipsing -- stars flare -- stars indi-vidual Algol

A Rapid-response Colorimetric and Fluorescent Probe for Cu2+ in Aqueous Media and Its Application to Real Sample

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A Rapid-response Colorimetric and Fluorescent Probe for Cu2+...

Effects of stimulation of medial amygdala on food intake of the rat and the possible mechanisms involved

“2011国际化学年在中国”——中国化学会第十届全国发光分析学术研讨会

作者： juan xue,Wen yang~*,Xiaoling Zhang~* (Key laboratory of Cluster Science of Ministr of Education,School of Chemistry,Beijing Institute of Technology,Beijing 100081)

Copper is an essential element in physical activities and plays an important role in organisms,the misregulation of copper ions(Cu) can lead to a series of severe *** it is necessary to monitor Cu in living samples and environmental *** to the various reported methods for detecting Cu,fluorescence probes have been proved to be more popular because of their sensitivity,specificity,and ease of ***,many probes developed are complicated,time-consuming,or have drawbacks in practical *** for,rapid-response probes are rather *** this work,we report an ICT-based effective colorimetric and fluorescent probe for Cu with advantages of rapid-response and *** addition 1 *** Cu,a remarkable color change from bright yellow to colorless could be observed by naked eye in 1 second;meanwhile,a linear range of 0-10μM(R = 0.9964) was obtained by fluorescence *** rapid detection of Cu in real sample with recoveries of 103.9%-101.5%demonstrated that the probe could be applied in vivo and to environmental ***,the fluorescence of the probe switched "on","off" and "on" rapidly by sequentially addition of Cu and S,which indicated it was a potential candidate for monitoring S in biological systems.

关键词： Colorimetric fluorescent probe Rapid-response Cu2+

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Effects of stimulation of medial amygdala on food intake of ...

高光谱技术结合特征波长筛选和支持向量机的哈密瓜成熟度判别研究

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： xue-juan yang,Jian-Qun YAN,Xiao-Lin ZHAO,Qi LEI Department of Physiology and Pathophysiology,Xi''an Jiaotong University,School of Medicine,Xi''an 710061

＜正＞Lesions of the amygdala have long been known to produce hyperphagia and obeisty in cats,dogs and monkeys. However,there were considerable arguments regarding the involvement of specific ***,the posterodorsal amygdala（PDA） is suggested as a possible effective site by small *** effect was more notable in female *** the mechanism is still not *** better understand whether PDA is a critical site in feeding behavior,we tested the change on food intake by acute electrical stimulation of the PDA of female *** possible mechanisms were also explored preliminarily,including the correlated hormones and the brain *** experiment 1,after 10 min of stimulation with 0.2 ms 100μA 50 HZ square-wave cathodal pulses on the unilateral PDA of female rats with 23h food deprivation,ad libitum food intake within lh was measured *** mean food consumption was（3.32±1.47） g（n = 10）,and singnificantly less than the control group[（8.93±2.17） g,n = 6,P ＜ 0.001].In experiment 2,using female rats which had fasted for 12h,the serum leptin concentration（RIA） and glucose were determined after 10 min of electrical stimulation （same parameters as in exp.l ） on the unilateral *** with control animals[（1.68±0.96） ng/mL,n = 4],mean serum leptin levels of the stimulation group[（3.95±1.64） ng/mL,n = 8) was *** was no significant difference in serum glucose between stimulation and control *** experiment 3,after 10 min of stimulation（same parameters as in exp.1） on the unilateral PDA of female rats with 23-h food deprivation,c-Fos-like immunoreactivity（c-FLI） in special brain regions was *** c-FLI was seen in hypothalamic nuclei including arcuate nucleus（ARC） and dorsal part of dorsomedial nucleus（DMD）),posterior part of paraventricular thalamic nucleus（PVP）,and area postrema（AP）.Moderate c-FLI was found in the parabrachial nuclei（PBN） and nucleus tractus solitarius（NTS）.These preliminary results,along

关键词： feeding Amygdala leptin c-Fos

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光谱学与光谱分析 2017年第7期37卷 2184-2191页

作者：孙静涛马本学董娟杨杰徐洁蒋伟高振江石河子大学食品学院新疆石河子832000 石河子大学机械电气工程学院新疆石河子832000 中国农业大学工学院北京100083

可溶性固形物含量(SSC)和硬度是哈密瓜划分等级的重要指标,同时也是其成熟度的表征因子。因此,为满足哈密瓜自动化分级和适宜采摘,采用高光谱技术结合特征波长筛选的方法,同时对哈密瓜的可溶性固形物含量、硬度及成熟度进行了无损检测... 详细信息

可溶性固形物含量(SSC)和硬度是哈密瓜划分等级的重要指标,同时也是其成熟度的表征因子。因此,为满足哈密瓜自动化分级和适宜采摘,采用高光谱技术结合特征波长筛选的方法,同时对哈密瓜的可溶性固形物含量、硬度及成熟度进行了无损检测研究。对多元散射校正(MSC)处理后的光谱分别利用连续投影算法(SPA)、竞争性自适应重加权算法(CARS)和CARS-SPA方法筛选了哈密瓜可溶性固形物和硬度的特征波长,并将原始光谱、MSC预处理后的光谱和所筛选的特征波长作为输入变量分别建立哈密瓜可溶性固形物和硬度的支持向量机(SVM)预测模型及成熟度判别模型。结果显示,MSC-CARS-SPA方法所建立的可溶性固形物和硬度SVM预测模型最优,其Rpre,RMSEP和RPD分别为0.940 4,0.402 7,2.94 1和0.825 3,35.22,1.771。同时对哈密瓜成熟度进行了判别分析,并分别建立了基于全光谱、单一的可溶性固形物或硬度特征波长和主成分分析(PCA)特征融合的哈密瓜成熟度SVM判别模型。结果显示,CARS-PCASVM模型的判别结果与全光谱SNV-SVM模型相同,其校正集和预测集判别正确率分别为95%和94%。研究表明,利用高光谱技术结合特征波长筛选方法可实现同时对哈密瓜可溶性固形物和硬度的定量预测及成熟度判别。

关键词：高光谱哈密瓜可溶性固形物硬度成熟度特征波长判别分析

Enhancing output performance of triboelectric nanogenerator by increasing charge storage capacity of electrodes

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Nano Research 2025年第1期18卷 395-403页

作者： Congcong Hao Zekun Wang Mingzhe Cai Shuaining Cheng Zhongxin Wang Cong Zhai juan Cui Yongqiu Zheng Chenyang xue Key Laboratory of Instrumentation Science and Dynamic Measurement Ministry of Education North University of ChinaTaiyuan 030051China

ABSTRACT:The practical application of rotating triboelectric nanogenerators is often limited by the wear of high-friction surface materials and low surface charge *** addition to the charge pump replenishment strategy,suppressing charge decay is also crucial for increasing surface charge ***,we present a high performance rotary triboelectric nanogenerator(HPR-TENG)based on a coplanar charge pumping strategy and polyvinyl chloride(PVC)*** has been demonstrated that applying PVC film to the surface of the storage electrode of the main TENG(M-TENG)significantly enhances the M-TENG’s output ***,the HPR-TENG with three layers of PVC film pasted achieved the best output performance,with a peak-topeak output voltage of 2828 V,a peak-to-peak output current of 327μA and a charge transfer of 0.81μC at 500 *** addition,the output improvement effects of different materials are *** TENG with 3 layers of PVC film pasted on it has a maximum output power of 748 mW at a load resistance of 4×10^(6)Ω.HPR-TENG’s output performance remains consistent after 100,000 cycles,which shows excellent *** excellent electrical performance of the HPR-TENG can be used as the energy supply for the tip high-voltage breakdown sensor system,which can achieve 14 breakdowns in 10 *** to its extraordinary electrical performance,HPRTENG can not only serve as an energy supply for cutting-edge high-voltage breakdown sensor systems,but also has the potential to serve as an energy supply for high-pressure sterilization,high-pressure vacuum and water electrolysis.

关键词： triboelectric nanogenerator coplanar charge pump enhancing charge density suppressing charge decay polyvinyl chloride(PVC)film

Stimulation of the posterodorsal amygdala suppresses estrogen receptor beta gene expression in the amygdala in female rats

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Stimulation of the posterodorsal amygdala suppresses estroge...