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Super Weak Compactness and Uniform Eberlein Compacta

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Acta Mathematica Sinica,English Series 2017年第4期33卷 545-553页

作者： zhi tao yang Yu Feng LU Qing Jin CHENG School of Mathematical Sciences Dalian University of Technology School of Mathematical Sciences Qinzhou University School of Mathematical Sciences Xiamen University

We prove that a topological space is uniform Eberlein compact iff it is homeomorphic to a super weakly compact subset C of a Banach space such that the closed convex hull coC of C is super weakly compact. We also show that a Banach space X is super weakly compactly generated iff the dual unit ball B;of X;in its weak star topology is affinely homeomorphic to a super weakly compactly convex subset of a Banach space.

关键词： Banach space uniform Eberlein compactas super weak compactness

A study of variable stars in the open cluster NGC 1582 and its surrounding field

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Research in Astronomy and Astrophysics 2016年第10期16卷 35-44页

作者： Fang-Fang Song Ali Esamdin Lu Ma Jin-Zhong Liu Yu Zhang Hu-Biao Niu tao-zhi yang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

This paper presents Charge-Coupled Device time-series photometric observations of the open cluster NGC 1582 and its surrounding field with Johnson B, V and R filters by using the Nanshan 1 m telescope administered by Xinjiang Astronomical Observatory. 19 variable stars and three variable candi- dates were detected in a 45＇ - 48.75＇ field around the cluster. 12 of the variable stars are newly-discovered variable objects. The physical properties, classifications and memberships of these 22 objects are studied through their light curves, their positions on the color-magnitude diagram and with archival data from the Naval Observatory Merged Astrometric Dataset. Among these objects, five are eclipsing binary systems, six are pulsating variable stars including one known 6 Scuti star and one newly-discovered RR Lyrae star. The distance to the RR Lyrae star is estimated to be 7.9 - 0.3 kpc, indicating that the star is located far behind the cluster. Four variable stars are probable members of the cluster, and 13 of the 22 objects are confirmed to be field stars.

关键词： NGC 1582 -- open cluster -- variable stars -- multi-color observation -- magnitude

Polymorphisms of microsomal triglyceride transfer protein in different hepatitis B virus-infected patients

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World Journal of Gastroenterology 2008年第35期14卷 5454-5460页

作者： zhi-tao yang Xin-Xin Zhang Xiao-Fei Kong Dong-Hua Zhang Shen-Ying Zhang Jie-Hong Jiang Qi-Ming Gong Gen-Di Jin zhi-Meng Lu Pole Sino-Francais de Recherches en Science du Vivant et Genomique Ruijin Hospital 197 Ruiiin Er Road Shanghai 200025 China Department of Infectious Diseases Ruijin Hospital 197 Ruijin Er Road Shanghai 200025 China

AIM: To identify the two polymorphisms of microsomal triglyceride transfer protein (MTP) gene in the Chinese population and to explore their correlation with both hepatitis B virus (HBV) self-limited infection and persistent infection. METHODS: A total of 316 subjects with self-limited HBV infection and 316 patients with persistent HBV infection (195 subjects without familial history), matched with age and sex, from the Chinese Han population were enrolled in this study. Polymorphisms of MTP at the promoter region -493 and at H297Q were determined by the allele specific polymerase chain reaction (PCR). RESULTS: The ratio of males to females was 2.13:1 for each group and the average age in the self-limited and chronic infection groups was 38.36 and 38.28 years, respectively. None of the allelic distributions deviated significantly from that predicted by the Hardy-Weinberg equilibrium. There was a linkagedisequilibrium between H297Q and -493G/T (D’ = 0.77). As the χ2 test was used, the genotype distribution of MTP -493G/T demonstrated a significant difference between the self-limited infection group and the entire chronic group or the chronic patients with no family history (χ2 = 8.543, P = 0.015 and χ2 = 7.199, P = 0.019). The allele distribution at the MTP-493 position also demonstrated a significant difference between the study groups without family history (χ2 = 6.212, P = 0.013). The T allele emerged as a possible protective factor which may influence the outcomes of HBV infection (OR: 0.59; 95% CI: 0.389-0.897). CONCLUSION: The polymorphism of the MTP gene, T allele at -493, may be involved in determining the HBV infection outcomes, of which the mechanism needs to be further investigated.

关键词： Hepatitis B virus Microsomal triglyceride transfer protein Single nucleotide polymorphism Self-limited HBV infection Chronic hepatitis B Clinicaloutcomes

KIC 5197256:an eclipsing binary containing a δ Scuti variable star

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Research in Astronomy and Astrophysics 2021年第9期21卷 111-123页

作者： Cheng-Long Lv Ali Esamdin Jun-Hui Liu Xiang-Yun Zeng tao-zhi yang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Department of Astronomy Xiamen UniversityXiamen 361005China School of Physics Xi'an Jiaotong UniversityXi’an 710049China

This paper reports analysis of an eclipsing binary system KIC 5197256 with aδSct variable *** light-curve modeling,several stellar parameters are derived,e.g.,temperature,mass,and mass *** O-C diagram is a straight line with a negative slope which means that its period is almost constant for about 2 *** analyses are performed for the residual light curve after subtracting the binary *** frequency spectrum reveals that one component star is aδScuti *** frequency separation is cross-identified with the histogram graph and the Fourier transform *** on the large separation and density relationship,the mean density of theδSct component is estimated to be 0.05 g·*** frequencies with the same frequency spacing in the range of 25 d-1-34 d-1 are ***,the pulsation amplitudes ofδSct stars increase with decreasing of rotations,so we propose that KIC 5197256 might have a relatively large rotational velocity,and the frequency f10 might be the rotation frequency.

关键词： binaries:eclipsing-stars:individual:KIC 5197256 stars:variables:δScuti stars:oscillations

Pulsations of the High-Amplitude δ Scuti star YZ Bootis

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Research in Astronomy and Astrophysics 2018年第1期18卷 11-20页

作者： tao-zhi yang Ali Esamdin Jian-Ning Fu Hu-Biao Niu Guo-Jie Feng Fang-Fang Song Jin-Zhong Liu Lu Ma Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China University of Chinese Academy of Sciences Beijing 100049 China Department of Astronomy Beijing Normal University Beijing 100875 China

We present a study on pulsations of the high-amplitudeδScuti star YZ Boo based on photometric observations in Johnson V and R bands with both the Nanshan 1-m telescope of Xinjiang Astronomical Observatory（XAO）and the Xinglong 85-cm telescope of National Astronomical Observatories,Chinese Academy of Sciences（NAOC）.Fourier analysis of the light curves reveals the fundamental radial mode and its five harmonics,with the fourth and fifth being newly *** new times of maximum light are determined from the light curves,and combined with those in the literature,we construct the O-C diagram,derive a new ephemeris and determine a new value for the updated period of 0.104091579（2）.In addition,the O-C diagram reveals an increasing rate of period change for YZ *** models are calculated and constrained with the observationally determined parameters of YZ *** mass and age of YZ Boo are hence derived as M=1.61±0.05 M_⊙ and age=（1.44±0.14）×10~9 yr,*** both the frequency of the fundamental radial mode and the rate of period change,YZ Boo is located at the post main sequence stage.

关键词： stars:variables:δ Scuti star stars:individual(YZ Boo) stars:oscillations

Effects of fluid balance on prognosis of acute respiratory distress syndrome patients secondary to sepsis

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World Journal of Emergency Medicine 2020年第4期11卷 216-222页

作者： Yu-ming Wang Yan-jun Zheng Ying Chen Yun-chuan Huang Wei-wei Chen Ran Ji Li-li Xu zhi-tao yang Hui-qiu Sheng Hong-ping Qu En-qiang Mao Er-zhen Chen Department of Emergency Ruijin Hospital Affi liated to Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Critical Care Medicine Ruijin Hospital Affi liated to Shanghai Jiao Tong University School of MedicineShanghaiChina

BACKGROUND:Fluid management is crucial to acute respiratory distress syndrome(ARDS)secondary to ***,choices of fluid resuscitation strategies and fluid input volumes remain a thorny *** study aimed to elucidate the relationship between fluid balance and prognosis of ARDS patients secondary to ***:Our study included 322 sepsis patients from Ruijin Hospital between 2014 and 2018,and 84 patients were diagnosed as ARDS within 72 hours after onset of sepsis according to Berlin ARDS Defi ***:Among the 322 sepsis patients,84(26.1%)were complicated with ARDS within 72 *** patients had a lower oxygenation index(PaO2/FiO2166.4±71.0 vs.255.0±91.2,P<0.05),longer duration of mechanical ventilation(11[6-24]days vs.0[0-0]days,P<0.05)than those without *** patients with ARDS showed daily positive net fl uid balance during seven days compared with those without ARDS who showed daily negative net fluid balance since the second day with signifi cant statistical *** the 84 sepsis patients with ARDS,58(69.0%)*** daily fl uid input volumes were much lower in survivors than in non-survivors(43.2±16.7 mL/kg vs.51.0±25.2 mL/kg,P<0.05)while output volumes were much higher in survivors(45.2±19.8 mL/kg vs.40.2±22.7 mL/kg,P<0.05).Using binary logistic regression analysis,we found that the mean daily fl uid balance was independently associated with mortality of sepsis patients complicating with ARDS(P<0.05).CONCLUSIONS:Early negative fluid balance is independently associated with a better prognosis of sepsis patients complicated with ARDS.

关键词： Sepsis Acute respiratory distress syndrome Fluid balance Prognosis

KIC 10417986:Spectroscopic Confirmation of the Nature of the Binary System with aδScuti Component

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Research in Astronomy and Astrophysics 2022年第10期22卷 49-60页

作者： Guo-Jie Feng Ali Esamdin Jian-Ning Fu Hu-Biao Niu Peng Zong tao-zhi yang Shu-Guo Ma Jing Xu Chun-Hai Bai Yong Wang Wei-Chao Sun Xin-Liang Wang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumgiXinjang 830011China University of Chinese Academy of Sciences Beijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi'an Jiaotong University710049 Xi'anChina

KIC 10417986 is a short orbital period(0.0737 day)ellipsoidal variable star with aδSct andγDor hybrid pulsation component discovered by *** ground-based spectroscopic observations were carried out in the winters of 2020 and 2021 to investigate the binary nature of this *** derive the orbital parameters using the rvfit code with a result of K_(1)=29.7±1.5 km s^(-1),γ=-18.7±1.7 km s^(-1),and confirm an orbital period of 0.84495 day instead of the result given by *** atmospheric parameters of the primary are determined by the synthetic spectral fitting technique with the estimated values of T_(eff)=7411±187 K,log g=4.2±0.3 dex,[M/H]=0.08±0.09 dex and vsini=52±11 km s^(-1).KIC 10417986 is a circular orbit binary *** the single-lined nature and mass function of the star,the derived orbital inclination is 26°±6°,and the mass of the secondary is 0.52_(-0.09)^(+0.18)M_(⊙),which should be a late-K to early-M type *** frequencies are extracted from Kepler light curves,of which six independent frequencies in the high-frequency region are identified as the p-mode pulsations ofδSct star,and one independent frequency in the low-frequency region(f_(2)=1.3033 cd^(-1))is probably the rotational frequency due to the starspots rather than the ellipsoidal effect.

关键词： techniques spectroscopic-(stars:)binaries spectroscopic-stars individual(KIC 10417986)-stars oscillations(including pulsations)-stars variables delta Scuti-(stars:)starspots

Nitrogen doping/infusion of 650 MHz cavities for CEPC

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Nuclear Science and Techniques 2021年第5期32卷 17-23页

作者： Peng Sha Jian-Kui Hao Wei-Min Pan Lin Lin Hong-Juan Zheng Xin-Ying Zhang Fang Wang Ji-Yuan Zhai Zheng-Hui Mi Fei-Si He Shu Chen Bai-Qi Liu zhi-tao yang Chao Dong Zhong-Quan Li State Key Laboratory of Nuclear Physics and Technology&Institute of Heavy Ion Physics Peking UniversityBeijing 100871China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Acceleration Physics and Technology Chinese Academy of SciencesBeijing 100049China Center for Superconducting RF and Cryogenics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The nitrogen doping/infusion of 650 MHz cavities for the circular electron positron collider(CEPC)is investigated in this *** 650 MHz 1-cell cavities are first treated via buffered chemical polishing(BCP),followed by nitrogen doping.A"2/6"condition is adopted,similar to that for 1.3 GHz cavities of Linear Coherent Light Source *** quality factor of both cavities improved to 7×10^(10)in low fields,i.e.,higher than that obtained from the baseline *** 650 MHz two-cell cavity is nitrogen infused at 165℃for 48 h with a BCP surface *** intrinsic quality factor(Q0)reached6×10^(10)at 22 MV/m in the vertical test,and the maximum gradient is 25 MV/m,which exceeds the specification of the CEPC(4×10^(10)at 22 MV/m).

关键词： Superconducting radio frequency cavity Nitrogen doping Nitrogen infusion Quality factor Accelerating gradient

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频率对半导体器件热击穿影响的理论模型

物理学报 2017年第1期66卷 334-339页

作者：张存波闫涛杨志强任伟涛朱占平西北核技术研究所高功率微波技术重点实验室西安710024

针对半导体器件中的热击穿,通过分析已有的理论模型,把频率对器件热区热产生和热传导的影响引入理论模型.利用格林函数求解热传输方程,同时对余误差函数进行近似处理,求解得到热区温度以及器件烧毁功率与频率和脉冲宽度的表达式.通过数... 详细信息

针对半导体器件中的热击穿,通过分析已有的理论模型,把频率对器件热区热产生和热传导的影响引入理论模型.利用格林函数求解热传输方程,同时对余误差函数进行近似处理,求解得到热区温度以及器件烧毁功率与频率和脉冲宽度的表达式.通过数值分析,求解得到不同频率下器件烧毁功率随脉冲宽度的变化规律以及不同脉冲宽度下器件烧毁功率随频率的变化规律,同时给出了频率对器件烧毁功率影响的物理解释.

关键词：热击穿频率脉冲宽度理论分析