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Manifestations of bright points observed in G-band and CaⅡH by Hinode/SOT

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Research in Astronomy and Astrophysics 2018年第10期18卷 85-96页

作者： yan-xiao liu Ning Wu Jun Lin Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China School of Tourism and Geography Yunnan Normal UniversityKunming 650500China

An algorithm was developed for identifying and tracking a magnetic bright point, or bright point （BP） for short, observed in both the photosphere （G-band） and chromosphere （Ca II H）, as well as for pairing a photospheric BP （PBP） with its conjugate chromospheric BP （CBP）. Two sets of data observed by Hinode/SOT in the quiet Sun near the disk center were analyzed. About 278 PBP-CBP pairs were identified and tracked. Lifetimes of both the PBPs and CBPs follow an exponential distribution with average lifetimes of 174 s and 163 s, respectively. We found that the differences in appearance time, in disappearance time and in lifetime of the two kinds of BPs all follow Gaussian distributions,which may indicate that the mechanisms of PBP and CBP formation/disintegration are different. However, the lifetimes of PBPs and CBPs are positively correlated with one another, with a correlation coefficient of 0.8. Furthermore, we calculated the horizontal displacement between the PBP and its conjugate CBP, which follows a Gaussian function with an average and standard deviation of （67.7 ± 38.5）km. We also calculated the amplitude of the flux tube shape change which might be caused by MHD waves propagating along the flux tube, and found that it follows an exponential distribution very well.

关键词： Sun photosphere - Sun chromosphere - methods observational - techniques image processing

First-principles study of structural and opto-electronic characteristics of ultra-thin amorphous carbon films

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Chinese Physics B 2022年第1期31卷 434-444页

作者： xiao-yan liu Lei Wang Yi Tong College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China

Most amorphous carbon(a-C)applications require films with ultra-thin thicknesses;however,the electronic structure and opto-electronic characteristics of such films remain unclear so *** address this issue,we developed a theoretical model based on the density functional theory and molecular dynamic simulations,in order to calculate the electronic structure and opto-electronic characteristics of the ultra-thin a-C films at different densities and *** was found to have a weak influence over the resulting electronic structure and opto-electronic characteristics,whereas density had a significant influence on these *** volume fraction of sp3 bonding increased with density,whereas that of sp2 bonding initially increased,reached a peak value of 2.52 g/cm^(3),and then decreased ***,the extinction coefficients of the ultra-thin a-C films were found to be density-sensitive in the long-wavelength *** implies that switching the volume ratio of sp2 to sp3 bonding can effectively alter the transmittances of ultra-thin a-C films,and this can serve as a novel approach toward photonic memory ***,the electrical resistivity of the ultra-thin a-C films appeared independent of *** implicitly indicates that the electrical switching behavior of a-C films previously utilized for non-volatile storage applications is likely due to an electrically induced effect and not a purely thermal consequence.

关键词： amorphous carbon density optical properties electronic structure density functional theory

Robust Stability of a Class of Fractional Order Hopfield Neural Networks

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Journal of Electronic Science and Technology 2015年第2期13卷 153-157页

作者： xiao-Lei liu Ming-Jiu Gai Cui-Ling Ma xiao-yan liu Institute of System Science and Mathematics Naval Aeronautical and Astronautical University

As the theory of the fractional order differential equation becomes mature gradually, the fractional order neural networks become a new *** robust stability of a class of fractional order Hopfield neural network with the Caputo derivative is investigated in this paper. The sufficient conditions to guarantee the robust stability of the fractional order Hopfield neural networks are derived by making use of the property of the Mittag-Leffler function, comparison theorem for the fractional order system, and method of the Laplace integral transform. Furthermore, a numerical simulation example is given to illustrate the correctness and effectiveness of our results.

关键词： fractional Laplace guarantee hotspot mature derivative illustrate Liouville correctness asymptotic

A Linear Perturbed Palais-Smale Condition for Lower Semicontinuous Functions on Banach Spaces

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Acta Mathematica Sinica,English Series 2008年第11期24卷 1853-1860页

作者： Li Xing CHENG xiao yan liu Mai Fang ZUO Department of Mathematics Xiamen University Xiamen 361005 P. R. China

This paper introduces a notion of linear perturbed Palais-Smale condition for real-valued functions on Banach spaces. In terms of strongly exposed points, it presents a characterization which guarantees linear perturbed Palais-Smale condition holds for lower semicontinuous functions with bounded effective domains defined on a Banach space with the Radon-Nikody＇m property; and gives an example showing that linear perturbed P-S condition is strictly weaker than the P-S condition.

关键词： Palais-Smale condition variational question perturbed optimization Radon-Nikody'm property Banach space

COPOLYMERIZATION OF ETHYLENE AND 1-HEXENE WITH TiCl_4/MgCl_2 CATALYSTS MODIFIED BY 2,6-DIISOPROPYLPHENOL

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Chinese Journal of Polymer Science 2013年第1期31卷 110-121页

作者： Sheng-jie Xia Zhi-sheng Fu xiao-yan liu 范志强 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

A supported TiCl4/MgCl2 catalyst without internal electron donor （O-cat） was prepared firstly. Then it was modified by 2,6-diisopropylphenol to make a novel modified catalyst （M-cat）. These two catalysts were used to catalyze ethylene/l-hexene copolymerization and l-hexene homopolymerization. The influence of cocatalyst and hydrogen on the catalytic behavior of these two catalysts was investigated. In ethylene/l-hexene copolymerization, the introduction of 2,6- iPr2C6H3O- groups did not deactivate the supported TiCl4/MgCl2 catalyst. Although the 1-hexene incorporation in ethylene/1- hexene copolymer prepared by M-cat was lower than that prepared by O-cat, the composition distribution of the former was narrower than that of the latter. Methylaluminoxane （MAO） was a more effective activator for M-cat than triisobutyl- aluminium （TIBA）. MAO led to higher yield and more uniform chain structure. In 1-hexene homopolymerization, the presence of 2,6-ipr2C6H3O- groups lowered the propagation rate constants. Two types of active centers with a chemically bonded 2,6-iprzCaH3O- group were proposed to explain the observed phenomena in M-cat.

关键词： Supported Ziegler-Natta catalyst 2,6-Diisopropylphenol Ethylene copolymerization Active center distribution.

Research progress of integrated traditional Chinese and Western medicine in the treatment of advanced gastric cancer

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World Journal of Gastrointestinal Oncology 2023年第1期15卷 69-75页

作者： Hui-Nan Ye xiao-yan liu Bao-Li Qin Department of Gastroenterology Cancer Hospital of China Medical University、Cancer Hospital of Dalian University of Technology、Liaoning Cancer Hospital&InstituteShenyang 110801Liaoning ProvinceChina

Gastric cancer(GC)is a malignant tumor originating from the gastric epithelium,and its incidence and mortality rates rank third among all malignant tumors *** is also one of the most common cancers in China and is treated predominantly by Western medicine in clinical ***,with the advancements in medical technology and informatics,the values of traditional Chinese medicine(TCM)in preventing and treating GC and improving prognosis have increasingly been *** to TCM,clinical manifestations of GC can be divided into Yege(dysphagia),regurgitation,stomach pain,and Zhengxia(abdominal mass).Due to the unbalanced distribution of health care resources in China,most GC patients already have progressive or advanced-stage disease at the first *** a result,most GC patients have poor physical function,and surgery or chemotherapy alone will aggravate the impairment to the immune function and seriously affect the quality of *** contrast,TCM therapies have shown promising efficacy in the management of these *** we review the role of the integrated TCM and Western medicine in treating advanced GC.

关键词： Integrated traditional Chinese medicine and Western medicine Advanced gastric cancer Research advances

Time-dependent crosstalk effects for image sensors with different isolation structures

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Chinese Physics B 2018年第8期27卷 640-644页

作者： Lei Shen Li-Qiao liu Hao Hao Gang Du xiao-yan liu Institute of Microelectronics Peking UniversityBeijing 100871China

Photo-generated carriers may diffuse into the adjacent cells to form the electrical crosstalk, which is especially no- ticeable after the pixel cell size has been scaled down. The electrical crosstalk strongly depends on the structure and electrical properties of the photosensitive areas. In this work, time-dependent crosstalk effects considering different isola- tion structures are investigated. According to the different depths of photo-diode （PD） and isolation structure, the transport of photo-generated carriers is analyzed with different regions in the pixel cell. The evaluation of crosstalk is influenced by exposure time. Crosstalk can be suppressed by reducing the exposure time. However, the sensitivity and dynamic range of the image sensor need to be considered as well.

关键词： image sensor crosstalk pixel isolation

Clinical efficacy and safety of erlotinib combined with chemotherapy in the treatment of advanced pancreatic cancer:A meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 921-931页

作者： xiao-yan liu Hong-Nian Pan Yue Yu Cheeloo College of Medicine Shandong UniversityJinan 250012Shandong ProvinceChina Department of Gastroenterology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Gastroenterology The Lu’an Hospital Affiliated to Anhui Medical UniversityThe Lu’an People's HospitalLu’an 237000Anhui ProvinceChina

BACKGROUND Advanced pancreatic cancer is resistant to chemotherapeutic drugs,resulting in limited treatment efficacy and poor *** administration of the chemotherapeutic gemcitabine and erlotinib is considered a potential first-line treatment for advanced pancreatic ***,their comparative benefits and potential risks remain *** To assess the clinical efficacy and safety of erlotinib combined with other chemotherapy regimens for the treatment of advanced pancreatic *** Literature on the clinical efficacy and safety of erlotinib combined with chemotherapy for advanced pancreatic cancer was retrieved through an online *** retrieved literature was subjected to a methodological qualitative assessment and was analyzed using the RevMan 5.3 *** randomized controlled trials involving 2444 patients with advanced pancreatic cancer were included in the *** Compared with chemotherapeutic treatment,erlotinib combined with chemotherapy significantly prolonged the progression-free survival time of pancreatic cancer patients[hazard ratio(HR)=0.78,95%CI:0.66-0.92,P=0.003].Meanwhile,the overall survival(HR=0.99,95%CI:0.72-1.37,and P=0.95)and disease control rate(OR=0.93,95%CI:0.45-0.91,P=0.84)were not significantly *** terms of safety,the erlotinib and chemotherapy combination was associated with a significantly higher risk of diarrhea(OR=3.59,95%CI:1.63-7.90,P<0.05)and rash(OR=3.63,95%CI:1.64-8.01,P<0.05)compared with single-agent ***,the risk of vomiting(OR=1.27,95%CI:0.62-2.59,P=0.51),regurgitation/anorexia(OR=1.61,95%CI:0.25-10.31,P=0.62),and infection(OR=0.72,95%CI:0.28-1.87,P=0.50)were not significant in either *** Compared with a single chemotherapeutic modality,erlotinib combined with gemcitabine can prolong progression-free survival in pancreatic cancer,but does not improve survival benefit or disease control rate,and can increase the risk of diarrhea and rash.

关键词： Erlotinib Chemotherapy Advanced pancreatic cancer Efficacy Safety Meta-analysis

Gauge Transformation and Constraint Induced Operator Ordering for Charged Rigid Planar Rotator in Uniform Magnetic Field

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Communications in Theoretical Physics 2006年第5X期46卷 843-844页

作者： LAI Mei-Mei WANG Xin xiao yan-Ping liu Quan-Hui School for Theoretical Physics and Department of Applied Physics Hunan University Changsha 410082 China

When the motion of a particle is constrained, excess terms exist using hermitian form of Cartesian momentum pi （i=1, 2,3） in usual kinetic energy （1/2/μ）∑ pi^2 , and the correct kinetic energy turns out to be （1/2μ） ∑1/ fipi f ipi, where fi are dummy factors in classical mechanics and nontrivial in quantum mechanics. In this paper the explicit form of the dummy functions fi is given for a charged rigid planar rotator in the uniform magnetic field with different gauge chosen. Under different gauges, we have different sets of dummy factors. It means that these factors do not have direct observable effect.

关键词： operator ordering gauge transformation quantum mechanics