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Spectral variations of carbon stars based on ISO SWS data

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Research in Astronomy and Astrophysics 2009年第12期9卷 1359-1367页

作者： Xiao-Hong Yang pei-sheng chen Department of Physics Chongqing University Chongqing 400044 China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China

We investigate the spectral variations of seven carbon stars in the infrared using ISO SWS spectral data. Continuum variations of those carbon stars show that during the central star pulsations when carbon stars become fainter in the infrared, their ISO SWS spectra become redder and the near-IR temperature （Tnir） decreases. When carbon stars become brighter in the infrared, their ISO SWS spectra become bluer and Tnir increases. Furthermore, it is found that the shorter 1abe wavelength of spectral features, such as the 2.48＋2.58 （C2H2＋HCN＋CO＋C2）, 3.05 （C2H2＋HCN） and 3.90 （C2H2） μm features, is, the better the correlation of their relative integrated fluxes with the fluxes of the continuum is. The changes of the 5.2 （C3）, 11.30 （SIC） and 13.70 （C2H2）μm features do not obviously correlate with the fluxes of the continuum.

关键词： stars: AGB and post-AGB -- stars: mass loss -- infrared: stars

Infrared spectral evolution of carbon stars

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Research in Astronomy and Astrophysics 2010年第4期10卷 363-382页

作者： pei-sheng chen Xiao-Hong Yang Hong-Guang Shan National Astronomical Observatories /Yunnan Observatory and Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Physics Chongqing UniversityChongqing 400044China

We collected almost all Highly Processed Data Products （HPDP） of ISO SWS01 spectra for the Galactic visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich proto-planetary nebulae （PPNs）.Those infrared spectra are primarily analyzed and *** is shown that either spectral shapes/peaks,or main molecular/dust features are evidenced to change in the sequence of visual carbon stars,infrared carbon stars,extreme carbon stars and carbon-rich ***,in this sequence,continua are gradually changed from blue to red and locations of spectral peaks of continua are also gradually changed from short wavelengths to long *** addition,in this sequence,intensities of main molecular/dust features are also gradually changed from prominent in the short wavelengths to prominent in the long ***,from 2MASS and IRAS photometric data,the sequence is also *** in this paper strongly support the previous suggestion for the evolution sequence of carbon-rich objects in our Galaxy,that is the sequence of visual carbon stars → infrared carbon stars → extreme carbon stars → carbon-rich PPNs.

关键词： infrared:stars - stars:carbon - stars:late type

An Infrared Photometric Study of Galaxies with Extragalactic H_2O Maser Sources

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 657-668页

作者： pei-sheng chen Yi-Fei Gao Hong-Guang Shan National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011

All galaxies with extragalactic H2O maser sources observed so far are collected. With the 2MASS and the IRAS photometric data an infrared study is performed on those galaxies. By a comparison between the H2O maser detected sources and non-detected sources in the infrared it is indicated that infrared properties in the IRAS 12-25 #m and 60-100#m are important for producing H20 masers in galaxies. It is also found that the H20 maser galaxies with different nuclear activity types have rather different infrared properties mainly in the IRAS 12-60 μm region.

关键词： galaxies maser -- galaxies nuclei -- galaxies starburst -- infrared galaxies

The Chemical Classification of the AGB Star IRAS 17515-2407

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 551-554页

作者： pei-sheng chen and Pin Zhang1National Astronomical Observatories, Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 2Cosmic Ray Institute, Yunnan University, Kunming 650091 National Astronomical Observatories Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Cosmic Ray Institute Yunnan University Kunming 650091

The chemical classification of IRAS 17515-2407 has been debated for a longtime. Up to now there are two contenders, oxygen-rich or carbon-rich. We believe that IRAS17515-2407 is an oxygen-rich source: because (ⅰ) it shows the silicate self-absorbed emission; (ⅱ)in the near infrared-IRAS diagram it is located in the oxygen-rich object region and (ⅲ)particularly, it has detected SiO maser emission.

关键词： stars: AGB stars: chemical classification stars: maser infrared: stars

MOF-derived 1D CGO Cathode for Efficient Solid Oxide Electrolysis Cells

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Chemical Research in Chinese Universities 2024年第4期40卷 737-746页

作者： TIAN Jiayu SUN Qi LIU pei DAI Jiuyi CAI Yezheng XU Miao YE Tian-Nan chen Jie-sheng Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240P.R.China Zhangjiang Institute for Advanced Study Shanghai Jiao Tong UniversityShanghai200240P.R.China State Key Laboratory of Space Power-sources Shanghai Institute of Space Power-sourcesShanghai200245P.R.China

Solid oxide electrolysis cells(SOECs)provide a promising way for converting renewable energy into chemical ***,NiO/CGO(nickel-gadolinium doped ceria)cermet has shown its excellent properties in ionic and electronic conductivity under reducing ***,we developed a novel 1D NiO/CGO cathode through a cerium metal-organic framework(MOF)derived *** cathode’s 1D nanostructure integrated with a microchannel scaffold facilitates enhanced mass transport,providing vertically aligned pathways for CO_(2)and H_(2)O ***,the 1D framework increases the number of interfacial sites and reduces ion diffusion distances,thereby simplifying electron/ion ***,this advanced cathode achieved a significant breakthrough in SOEC performance,maintaining efficient CO_(2)and H_(2)O electrolysis at an extraordinary current density of 1.41 A/cm^(2)at 1.5 V and excellent stability over 24 h at 850℃.The enhanced performance of this newly developed cathode not only achieves a remarkable 100%improvement compared to those of NiO/CGO cathodes with varying geometrical configurations but also surpasses those of commercial NiO/CGO catalysts by an outstanding 40%when tested under identical *** development of the 1D NiO/CGO enhances the efficiency and durability of ceramic cathodes for CO_(2)and H_(2)O co-electrolysis in SOECs and improves the scalability and effectiveness of SOECs in renewable energy applications.

关键词： Cerium metal-organic framework One-dimensional structure Gadolinium doped ceria CO_(2)activation co-Electrolysis

Prognostic significance and relationship of SMAD3 phosphoisoforms and VEGFR-1 in gastric cancer:A clinicopathological study

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 118-132页

作者： Shi-Lin Lv pei Guo Jun-Rong Zou Ren-sheng chen Ling-Yu Luo De-Qiang Huang Hospital of Gastroenterology Institute of Digestive DiseasesThe First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Pathology Shenzhen Hospital of Southern Medical UniversityShenzhen 518000Guangdong ProvinceChina Institute of Urology The First Affiliated Hospital of Gannan Medical UniversityGanzhou 341000Jiangxi ProvinceChina Department of Pathology The First Affiliated Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer ***3 phosphorylation is a crucial prognostic marker in gastric *** To determine the prognostic value and relationship of SMAD3 phospho-isoforms and VEGFR-1 in gastric *** This was a single-center observational study which enrolled 98 gastric cancer patients and 82 adjacent normal gastric tissues from patients aged 32-84 years(median age 65)between July 2006 and April *** were followed up until death or the study ended(median follow-up duration of 28.5 mo).The samples were used to generate tissue microarrays(TMAs)for immunohistochemical(IHC)*** expressions of TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 in gastric cancer(GC)tumor tissue and normal tissue were measured by IHC staining using TMAs obtained from 98 GC *** and survival information of the patients was recorded by Outdo Biotech from May 2007 to July *** relationship between TGF-β1,pSMAD3C(S423/425),pSMAD3L(S204),and VEGFR-1 protein expression levels was analyzed using Pearson's correlation *** relationship between protein expression levels and clinicopathological parameters was analyzed using the Chi-squared test.A survival curve was generated using the Kaplan-Meier survival *** TGFβ-1 and VEGFR-1 expression was significantly upregulated in gastric cancer tissue compared to adjacent noncancerous *** positive expression of phosphorylated isoforms of Smad3 varied depending on the phosphorylation site[pSMAD3C(S423/425):51.0%and pSMAD3L(S204):31.6%].High expression of pSMAD-3L(S204)was significantly correlated with larger tumors(P=0.038)and later N stages(P=0.035).Additionally,high expression of VEGFR-1 was closely correlated with tumor size(P=0.015)and pathological grading(P=0.013).High expression of both pSMAD3L(S204)and VEGFR-1 was associated with unfavorable outcomes in terms of overall survival(OS).Multiva

关键词： Gastric cancer pSMAD3L(S204) pSMAD3C(S423/425) Survival Transforming growth factor-β1 VEGFR-1

Application Analysis of Multiple Neurons Connected with Fast Inhibitory Synapses

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Journal of Bionic Engineering 2024年第4期21卷 1905-1918页

作者： Wen Duan Weihai chen Jianhua Wang Zhongcai pei Jingmeng Liu Jianer chen School of Automation Science and Electrical Engineering Beihang UniversityXueyuan RoadBeijing100191China Hangzhou Innovation Institute Beihang UniversityChuanghui StreetHangzhou310051ZhejiangChina School of Electrical Engineering and Automation Anhui UniversityAnhui230601ZhejiangChina Zhejiang Rehabilitation Medical Center Binsheng RoadHangzhou310052ZhejiangChina

Almost all living organisms exhibit autonomic oscillatory activities,which are primarily generated by the rhythmic activities of their neural *** nonlinear oscillator models have been proposed to elucidate these neural behaviors and subsequently applied to the domain of robot ***,the oscillation patterns generated by these models are often unpredictable and need to be obtained through parameter *** study introduces a mathematical model that can be used to analyze multiple neurons connected through fast inhibitory *** characteristic of this oscillator is that its stationary point is stable,but the location of the stationary point changes with the system *** through reasonable topology and threshold parameter selection can the oscillation be *** study analyzed the conditions for stable oscillation in two-neuron networks and three-neuron networks,and obtained the basic rules of the phase relationship of the oscillator network established by this *** addition,this study also introduces synchronization mechanisms into the model to enable it to be synchronized with the sensing ***,this study used these theories to establish a robot single leg joint angle generation *** experimental results showed that the simulated robot could achieve synchronization with human motion,and had better control effects compared to traditional oscillators.

关键词： Oscillator Phase trajectory Synaptic threshold Synchronization Motion generation

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth