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Research in Astronomy and Astrophysics 2024年第8期24卷 147-156页

作者： Xuan Zhang Jin-Zhong Liu le-tian wang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and *** extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric *** morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/*** Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity *** mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,*** contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets.

关键词： comets general-comets individual(38P/Stephan-Oterma,64P/Swift-Gehrels,C/2017 M4(ATLAS))-techniques photometric

An Analysis of the Fragmentation of Observing Time At the Muztagh-Ata Site

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Research in Astronomy and Astrophysics 2024年第3期24卷 29-33页

作者： Wen-Bo Gu Jing Xu Guo-Jie Feng Xuan Zhang le-tian wang Xin-Liang wang Ali Esamdin Li-Xian Shen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 83001lChina School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Cloud cover plays a pivotal role in assessing observational conditions for astronomical *** for the fraction of observing time,its fragmentation also wields a significant influence on the quality of nighttime sky *** this article,we introduce the functionΓ∈[0,1],designed to comprehensively capture both the fraction of available observing time and its *** in situ measurement data gathered at the Muztagh-Ata site between 2017 and 2021,we showcase the effectiveness of our *** statistical result illustrates that the Muztagh-Ata site affords approximately 122 nights that were absolutely clear and 205 very good nights annually,corresponding toΓ≥0.9 andΓ≥0.36 respectively.

关键词： site testing-atmospheric effects-methods statistical

Coercivity Ageing Effect on FePt Nanoparticles in Mesoporous Silica via Stepwise Synthesis Strategy

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Chinese Physics letters 2018年第6期35卷 94-97页

作者： tian-le wang Zhi-Gang Li Li Zhang Wei-Ping Chen Shang-Shen Feng Wen-Wu Zhong College of Physics and Electronic Engineering Taizhou UniversityTaizhou 318000 Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou UniversityTaizhou 318000

FePt nanoparticles in mesoporous silica are fabricated by a simple stepwise synthesis strategy.A pre-annealing temperature-dependent coercivity-ageing effect in FePt nanoparticles is observed at room *** facecentered cubic（fcc）structured FePt nanoparticles,the ageing effect is sensitive to the pre-annealing temperature,especially when the temperature is close to the *** special magnetic behavior of FePt nanoparticles reveals that the physical properties gradually change between fee and face-centered tetragonal structures,and will deepen our understanding of the mechanism of such magnetism in FePt nanoparticles.

关键词： Coercivity Ageing Effect on FePt Nanoparticles in Mesoporous Silica via Stepwise Synthesis Strategy

Site-testing at the Muztagh-ata Site *** Cloud Amount during the Last Five Years

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Research in Astronomy and Astrophysics 2023年第4期23卷 164-171页

作者： Jing Xu Guo-jie Feng Guang-xin Pu le-tian wang Zi-Huang Cao Li-Qing Ren Xuan Zhang Shu-guo Ma Chun-hai Bai Ali Esamdin Jian Li Yuan tian Zheng wang Yong-heng Zhao Jian-rong Shi Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Urumqi Meteorological Satellite Ground Station Urumqi 830011China

The clarity of nights is the major factor that should be carefully considered for optical/infrared astronomical observatories in site-testing *** coverage is directly related to the amount of time available for scientific observations at *** this article,we report on the results of detailed night-time cloud statistics and continuous observing time derived from ground-based all-sky cameras(ASCs)at the Muztagh-ata site from 2017to *** obtained from acquisition data show that the proportion of the annual observing time at the Muztagh-ata site is 65%,and the best period with the least cloud coverage and longer continuous observing time is from September to *** made a comparison of the monthly mean observing nights obtained from our ASC and CLARA data set,and results show that the discrepancy between them may depend on the cloud top *** average,this site can provide 175 clear nights and 169 nights with at least 4 hr of continuous observing time per year.

关键词： site testing-atmospheric effects-methods statistical

Diabetes mellitus may affect the long-term survival of hepatitis B virus-related hepatocellular carcinoma patients after liver transplantation

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World Journal of Gastroenterology 2016年第43期22卷 9571-9585页

作者： Qing Zhang Yong-Lin Deng Chang Liu Li-Hong Huang lei Shang Xin-Guo Chen le-tian wang Jin-Zan Du Ying wang Pei-Xiao wang Hui Zhang Zhong-Yang Shen Institute of Liver Transplantation General Hospital of Chinese People’s Armed Police Forces Department of Transplant Surgery Tianjin First Central Hospital Department of Hepatobiliary Surgery First Affiliated Hospital School of Medicine Xi’an Jiaotong University Department of Health Statistics Faculty of Preventive Medicine Fourth Military Medical University Department of Gastroenterology Luoyang Dongfang Hospital

AIM to determine whether diabetes mellitus(DM) affects prognosis/recurrence after liver transplantation(Lt) for hepatitis B virus(HBV)-related hepatocellular carcinoma(HCC). METHODS A retrospective study was conducted between January 2000 and August 2013 on 1631 patients with HBV-related HCC who underwent Lt with antiviral prophylaxis. Patient data were obtained from the China Liver transplant Registry(https://***/). to compare the outcomes and tumor recurrence in the HBV-related HCC patients with or without DM, statistical analyses were conducted using χ2 tests, Mann-Whitney tests, the Kaplan-Meier method, log-rank tests and multivariate step-wise Cox regression analysis. RESULTS Univariate analysis of 1631 patients who underwent Lt found overall 1-, 3- and 5-year survival rates of 79%, 73% and 71% respectively in the DM patients, and 84%, 78% and 76% in the non-DM patients respectively. Overall survival rate differences after Lt between the two groups were significant(P = 0.041), but recurrence-free survival rates were not(P = 0.096). By stratified analysis, the overall survival rates in DM patients for age > 50 years(P = 0.002), the presence of vascular invasion(P = 0.096), tumors ≤ 3 cm(P = 0.047), two to three tumor nodules(P = 0.007), Child-Pugh grade B(P = 0.018), and preLt alanine aminotransferase levels between 40 and 80 IU/L(P = 0.017) were significantly lower than in non-DM patients. Additionally, serum α-fetoprotein level > 2000 ng/m L(P = 0.052) was associated with a significant survival difference trend between DM and non-DM patients. Multivariate analysis showed that the presence of DM(P < 0.001, HR = 1.591; 95%CI: 1.239-2.041) was an independent predictor associated with poor survival after Lt. CONCLUSION HBV-related HCC patients with DM have decreased long-term overall survival and poor Lt outcomes. Prevention strategies for HCC patients with DM are recommended.

关键词： Diabetes mellitus Hepatocellular carcinoma Hepatitis B virus Liver transplantation Survival

包容性创新推动区域经济增长的路径研究——基于跨越“中等收入陷阱”的视角

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研究与发展管理 2017年第1期29卷 75-85页

作者：湛泳徐乐王恬复旦大学管理学院上海200433 湘潭大学商学院湘潭411105

依据包容性创新的作用与跨越"中等收入陷阱"影响因素的契合性,找到了收入分配结构、内需和产业结构3条路径,利用我国30个省份的面板数据,结合中介效应模型,实证研究了包容性创新助推跨越"中等收入陷阱"3条路径的有效性,并从区域发展不... 详细信息

依据包容性创新的作用与跨越"中等收入陷阱"影响因素的契合性,找到了收入分配结构、内需和产业结构3条路径,利用我国30个省份的面板数据,结合中介效应模型,实证研究了包容性创新助推跨越"中等收入陷阱"3条路径的有效性,并从区域发展不平衡的角度出发,进一步分析了包容性创新对不同地区经济增长的影响.研究发现:包容性创新能够通过缩小收入差距、扩大内需和促进产业结构升级从而助推跨越"中等收入陷阱";分区域来看,包容性创新对跨越"中等收入陷阱"的助推力度呈现从东部到西部逐渐递增的态势.在以上结论的基础上,本文就如何通过包容性创新助推跨越"中等收入陷阱"提出了相应的政策建议.

关键词：包容性创新跨越“中等收入陷阱” 区域经济增长金字塔底层

Site-testing at Muztagh-ata site Ⅰ:ground meteorology and sky brightness

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Research in Astronomy and Astrophysics 2020年第6期20卷 162-174页

作者： Jing Xu Ali Esamdin Jin-Xin Hao Jin-Min Bai Ji Yang Xu Zhou Yong-Qiang Yao Jin-Liang Hou Guang-Xin Pu Guo-Jie Feng Chun-Hai Bai Peng Wei Shu-Guo Ma Abudusaimaitijiang Yisikandee le-tian wang Xuan Zhang Liang Ming Lu Ma Jin-Zhong Liu Zi-Huang Cao Yong-Heng Zhao Lu Feng Jian-Rong Shi Hua-Lin Chen Chong Pei Xiao-Jun Jiang Jian-Feng wang Jian-Feng tian Yan-Jie Xue Jing-Yao Hu Yun-Ying Jiang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yunnan Observatories Chinese Academy of SciencesKunming 650000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210008China

Site-testing is crucial for achieving the goal of scientific research and analysis of meteorological and optical observing conditions,one of the associated basic *** one of three potential sites to host the 12-meter Large Optical/infrared Telescope(LOT),the Muztagh-ata site,which is located on the Pamir Plateau in Xinjiang,in west China,began its site-testing task in the spring of *** this paper,we firstly start with an introduction to the site and then present a statistical analysis of the ground-level meteorological properties such as air temperature,barometric pressure,relative humidity,and wind speed and direction,recorded by an automatic weather station with standard meteorological sensors for a two-year *** also show the monitoring results of sky brightness during this period.

关键词： site testing meteorological condition optical observing

Site-testing at Muztagh-ata site Ⅲ:temperature inversion in surface-layer atmosphere

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Research in Astronomy and Astrophysics 2020年第6期20卷 185-192页

作者： Jing Xu Ali Esamdin Guo-Jie Feng Guang-Xin Pu Yi Hu Ke-Liang Hu Xu Yang Jin-Xin Hao Yan-Jie Xue Xu Zhou Shu-Guo Ma Abudusaimaitijiang Yisikandee le-tian wang Xuan Zhang Chun-Hai Bai Peng Wei Liang Ming Lu Ma Jin-Zhong Liu Yun-Ying Jiang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China

In this article,we present detailed seasonal,monthly and daily statistics of temperature difference in the surface layer at the Muztagh-ata site based on the temperature measurements at two heights of 2 m and6 *** find that temperature inversion occurs frequently at our site during nighttime,especially during the cold *** temperature inversion always represents stable atmospheric turbulence,which is crucial for an optical *** analyzing the behavior of temperature inversion and its correlation with wind and cloud amount,one conclusion can be made that radiation inversion is the main reason for the existence of temperature inversion in the surface-layer at the Muztagh-ata site.

关键词： site testing atmospheric turbulence temperature inversion

Site testing at Muztagh-ata site Ⅱ:seeing statistics

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Research in Astronomy and Astrophysics 2020年第6期20卷 175-184页

作者： Jing Xu Ali Esamdin Jin-Xin Hao Jin-Min Bai Ji Yang Xu Zhou Yong-Qiang Yao Jin-Liang Hou Guang-Xin Pu Guo-Jie Feng Chun-Hai Bai Peng Wei Shu-Guo Ma Abudusaimaitijiang Yisikandee le-tian wang Xuan Zhang Liang Ming Lu Ma Jin-Zhong Liu Zi-Huang Cao Yong-Heng Zhao Lu Feng Jian-Rong Shi Hua-Lin Chen Chong Pei Xiao-Jun Jiang Jian-Feng wang Jian-Feng tian Yan-Jie Xue Jing-Yao Hu Yun-Ying Jiang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yun nan Observatories Chin ese Academy of Scie ncesKun ming 650000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 21000&China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210008China

In this article,we present a detailed analysis of the statistical properties of seeing for the Muztaghata site which is a candidate site for hosting the future Chinese Large Optical/infrared Telescope(LOT)*** measurements were obtained with differential image motion monitors(DIMMs)from April2017 to November 2018 at different heights during different *** median seeings at 11 m and6 m are very close but significantly different from that on the *** mainly analyzed the seeing at11 m monthly and hourly,having found that the best season for observing was from late autumn to early winter and seeing tended to improve during the night only in *** analysis of the dependence on temperature inversion,wind speed and direction also was made and the best meteorological conditions for seeing are given.

关键词： site testing seeing

Fast and perfect state transfer in superconducting circuit with tunable coupler

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Chinese Physics B 2023年第11期32卷 247-251页

作者：张驰王天乐赵泽安杨小燕郭亮亮贾志龙段鹏郭国平 CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Origin Quantum Computing Company Limited Hefei 230026China

In quantum computation and quantum information processing, the manipulation and engineering of quantum systems to suit certain purposes are an ongoing task. One such example is quantum state transfer(QST), an essential requirement for both quantum communication and large-scale quantum computation. Here we engineer a chain of four superconducting qubits with tunable couplers to realize the perfect state transfer(PST) protocol originally proposed in quantum spin networks and successfully demonstrate the efficient transfer of an arbitrary single-qubit state from one end of the chain to the other,achieving a high fidelity of 0.986 in just 25 ns. This demonstrated QST is readily to extend to larger chain and multi-node configurations, thus serving as a desirable tool for scalable quantum information processing.

关键词： quantum state transfer superconducting circuit tunable coupler