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Discovery of two rotational modulation periods from a young hierarchical triple system

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中国科学:物理学、力学、天文学英文版 2023年第9期66卷 179-189页

作者： Yu-Tao Chen Hai-Jun Tian Min Fang xiao-Xiong zuo Sarah ABird Di Liu Xin-Yu Zhu Peng Zhang Gao-Chao Liu Sheng Cui Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443002China School of Science HangZhou Dianzi UniversityHangZhou 310018China Space Information Research Institute Hangzhou Dianzi UniversityHangZhou 310018China School of Physics and Astronomy China West Normal UniversityNanChong 637002China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

GW Ori is a young hierarchical triple system located in λ Orionis, consisting of a binary(GW Ori A and B), a tertiary star(GW Ori C) and a rare circumtriple disk. Due to the limited data with poor accuracy, several short-period signals were detected in this system, but the values from diferent studies are not fully consistent. As one of the most successful transiting surveys, the transiting exoplanet survey satellite(TESS) provides an unprecedented opportunity to make a comprehensive periodic analysis of GW Ori. In this work we discover two significant modulation signals by analyzing the light curves of GW Ori's four observations from TESS, i.e.,(3.02 ± 0.15) and(1.92 ± 0.06) d, which are very likely to be the rotational periods caused by starspot modulation on the primary and secondary components, respectively. We calculate the inclinations of GW Ori A and B according to the two rotational periods. The results suggest that the rotational plane of GW Ori A and B and the orbital plane of the binary are almost coplanar. We also discuss the aperiodic features in the light curves;these may be related to unstable accretion. The light curves of GW Ori also include a third(possible) modulation signal with a period of(2.51±0.09) d, but the third is neither quite stable nor statistically significant.

关键词： GW Ori pre-main sequence fundamental parameters triple stars

Air pressure law of a reservoir constructed in karst sinkholes

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Journal of Mountain Science 2024年第3期21卷 1048-1057页

作者： YU Bo TAI Shengping ZHENG Kexun CHEN Shiwan HAN xiao WANG Senlin zuo Shuangying Power China Guiyang Engineering Corporation Limited Guiyang 550081China College of Resources and Environmental Engineering Key Laboratory of Karst Georesources and EnvironmentMinistry of EducationGuizhou UniversityGuiyang 550025China

Karst sinkholes with natural negative landform provide favorable conditions for the pumped storage reservoir construction for less excavation ***,the construction of the reservoir would plug the natural karst channels for water and air,which would cause remarkable air pressure in karst channels when the groundwater level fluctuates.A large laboratory simulation test was carried out to study the air pressure variation of a reservoir built on the karst *** air pressure in the karst channel and inside the model was monitored during the groundwater rising and falling *** showed that the variation of air pressure in the karst channel and the surrounding rock exhibited a high degree of *** air pressure increased rapidly at the initial stage of water level rising,followed by a slight decrease,then the air pressure increased sharply when the water level approached the top of the karst *** initial peak of air pressure and the final peak of air pressure were defined,and both air pressure peaks were linearly increasing with the water level rising *** negative air pressure was also analyzed during the drainage process,which was linearly correlated with the water level falling *** causes of air pressure variation in karst channels of a pumped storage reservoir built on the karst sinkhole were *** initial rapid increase,then slight decrease and final sudden increase of air pressure were controlled by the combined effects of air compression in karst channel and air seepage into the surrounding *** the drainage process,the instant negative air pressure and gradual recovering of air pressure were controlled by the combined effects of negative air pressure induced by water level falling and air supply from surrounding *** work could provide valuable reference for the reservoir construction in karst area.

关键词： Simulation test Karst sinkhole Pumped storage reservoir Air pressure Flow rate

Banana-shaped electron acceptors with an electron-rich core fragment and 3D packing capability

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Carbon Energy 2023年第1期5卷 123-133页

作者： Pengqi Li Xianyi Meng Ke Jin Zhiwei Xu Jianqi Zhang Lixiu Zhang Chuang Niu Furui Tan Chenyi Yi zuo xiao Yaqing Feng Guan-Wu Wang Liming Ding School of Chemical Engineering and Technology Tianjin UniversityTianjinChina Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS) Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Chemistry University of Science and Technology of ChinaHefeiChina Key Laboratory of Photovoltaic Materials Henan UniversityKaifengChina Department of Electrical Engineering Tsinghua UniversityBeijingChina

The emergence of Y6-type nonfullerene acceptors has greatly enhanced the power conversion efficiency(PCE)of organic solar cells(OSCs).However,which structural feature is responsible for the excellent photovoltaic performance is still under *** this study,two Y6-like acceptors BDOTP-1 and BDOTP-2 were *** from previous Y6-type acceptors featuring an A–D–Aʹ–D–A structure,BDOTP-1,and BDOTP-2 have no electron-deficient Aʹfragment in the core ***,there is an electron-rich dibenzodioxine fragment in the *** this modification leads to a marked change in the molecular dipole moment,electrostatic potential,frontier orbitals,and energy levels,BDOTP acceptors retain similar three-dimensional packing capability as Y6-type acceptors due to the similar banana-shaped molecular *** acceptors show good performance in *** PCEs of up to 18.51%(certified 17.9%)are *** study suggests that the banana-shaped configuration instead of the A–D–Aʹ–D–A structure is likely to be the determining factor in realizing high photovoltaic performance.

关键词： 3D packing capability core fragment molecular configuration nonfullerene acceptors organic solar cells

Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy

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Nuclear Science and Techniques 2024年第3期35卷 170-180页

作者： Yi-Nan Zhu zuo-Kang Lin Hai-Yan Yu Ye Dai Zhi-Min Dai xiao-Han Yu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Science Beijing 100049China

Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear *** various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT ***^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional *** study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head *** study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 ***,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes.

关键词： Boron neutron capture therapy ^(7)Li(p,n)7Be neutron source Incident proton energy Monte Carlo simulation

基于模糊数学感官评价法的山楂红枣固体饮料研究

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饮料工业 2024年第1期27卷 10-21页

作者：邓斌李想周立权娄可轩周一苗肖作为湖南中医药大学药食同源创新实验室湖南长沙410208 湖南中医药大学药学院湖南长沙410208 湖南中医药大学湘杏学院湘阴校区湖南岳阳414615

以山楂、红枣、甘草等作为主要材料,选择色泽、气味、滋味和组织状态四个指标作为固体饮料感官评价指标,建立模糊数学感官评价方法,获得各样品的感官综合评分,研制出一种山楂红枣固体饮料。通过单因素实验研究山楂与红枣比例、白砂糖添... 详细信息

以山楂、红枣、甘草等作为主要材料,选择色泽、气味、滋味和组织状态四个指标作为固体饮料感官评价指标,建立模糊数学感官评价方法,获得各样品的感官综合评分,研制出一种山楂红枣固体饮料。通过单因素实验研究山楂与红枣比例、白砂糖添加量、蜂蜜添加量对固体饮料感官评分的影响,并结合Box-Behnken响应面法,以感官评分为标准,考察山楂与红枣质量比、白砂糖添加量以及蜂蜜添加量这3个因素对整体感官评分的影响,并对最佳配方生产出来的山楂红枣固体饮料的理化性质以及口感风味进行检测和抗氧化活性评价。结果表明:当山楂与红枣质量比为1∶1.03,白砂糖添加量为12.12%,蜂蜜添加量为6.85%,此时固体饮料的感官评分最高为90.14分。在此条件下制得的固体饮料色泽均匀、酸甜适宜,溶解性较好,是一款营养健康的药食同源植物速溶固体饮料。经过理化检测,测得其多糖为45.01mg/g,总黄酮为1.605mg/g,绿原酸为0.096mg/g,原儿茶酸为0.0156mg/g。并且具有较强的自由基的清除能力,清除DPPH·和·OH的IC_(50)分别为18.58mg/mL、18.74mg/mL(以固体饮料中总酚计)。

关键词：模糊数学感官评价 Box-Behnken响应面

Hour-to-hour variability of the ionosphere: An application of the classical multidimensional scaling method

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Science China Earth Sciences 2015年第7期58卷 1243-1250页

作者： SHI Hao ZHANG DongHe HAO YongQiang xiao zuo Department of Geophysics Peking University

The classical multidimensional scaling(MDS) method is introduced and applied in the study of the hour-to-hour ionospheric variability based on the ionospheric fo F2 observed at three ionosonde stations in East-Asia in 2002 and 2007. Results from the matrix eigen decompositions indicate that the annual part of the ionospheric variation is large in middle latitude and solar maximum period(2002) while low in the low latitude and solar minimum period(2007). The connectivity maps of the hour-to-hour ionospheric variability based on MDS method show some common diurnal features. The ionospheric connectivity between adjacent hours near noon hours and near midnight hours is high. The ionospheric connectivity between adjacent hours near sunrise hours and near sunset hours is poor, especially for the sunrise hours. Also there are latitudinal and solar activity dependences in this kind of connectivity. These results revealed from the ionospheric connectivity maps are useful physically and in practice for the ionospheric forecasting on the hour-to-hour scale.

关键词：电离层预报小时应用多维太阳活动地图显示特征分解 DS方法

A theoretical analysis of global characteristics of spread-F

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Chinese Science Bulletin 2001年第19期46卷 1593-1595页

作者： zuo xiao Tianhua Zhang Peking Univ Dept Geophys Beijing 100871 Peoples R China

Spread-F is an important ionosphere pheonome-non and it has much effect on radio wave propogation. Taking magnetic inclination and declination into consideration, a theoretical model is deduced for the linear growth-rate of spread-F. It is a generalization of the earlier equatorial model and a relatively complete description o f the spread-F pheonomenon. This theory shows that the magnetic configuration, i.e. the magnetic strength, inclination and declination, affects the occurrence rate greatly, which forms some regional distribution characteristics of the spread-F.

关键词： spread-F irregularities global characteristics.

Study of the ionospheric TEC using GPS during the large solar flare burst on Nov. 6,1997

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Chinese Science Bulletin 2000年第19期45卷 1749-1752页

作者： Donghe Zhang zuo xiao Peking Univ Dept Geophys Beijing 100871 Peoples R China

Using the data from 15 global positioning system (GPS) stations scattered between 28° N-45° N and 90° W- 77° E we obtained the total electron content (TEC) variations with time during a large solar flare. The results indicated that the flare makes the TEC of ionosphere increasing in a large spatial area. The amounts of the TEC enhancement are mainly determined by the local time of subionospheric point, and the largest TEC enhancement is about 2.5 TECU. It is also concluded that the TEC enhancement is not symmetrical about the local noon time, the TEC enhancement values during morning hours are larger than those of the afternoon hours.

关键词： total electron content (TEC) flare subionospheric point.

基于CRISPR/Cas13a系统建立大口黑鲈弹状病毒检测方法

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水生生物学报 2024年第2期48卷 283-291页

作者：张敏琳黄枫淇左小玲梁建韬梁凯珊单金红李宗烊喻婕罗丽媛禤梓杰赵会宏王庆华南农业大学海洋学院广州510642 华南农业大学粤港海洋生物资源保护与开发联合实验室广州510642

为了建立一种灵敏度高、特异性强并且适合现场诊断的大口黑鲈弹状病毒(Micropterus salmoides rhabdovirus,MSRV)检测方法,研究基于CRISPR-Cas13a系统并结合多酶恒温核酸快速扩增(MIRA)技术建立了一种MSRV的检测方法。实验对MSRV序列进... 详细信息

为了建立一种灵敏度高、特异性强并且适合现场诊断的大口黑鲈弹状病毒(Micropterus salmoides rhabdovirus,MSRV)检测方法,研究基于CRISPR-Cas13a系统并结合多酶恒温核酸快速扩增(MIRA)技术建立了一种MSRV的检测方法。实验对MSRV序列进行多重序列比对分析后,针对MSRV衣壳蛋白(CP)基因的特异性区域设计两个靶点,并通过体外转录成特异性的crRNA,同时设计合成MIRA引物序列实现目标序列的等温扩增,最后结合Cas13a蛋白、crRNA、恒温扩增体系构建检测体系,并从高效crRNA的选择、反应温度、ssRNA报告探针浓度和Cas13a与crRNA的浓度比四个方面优化了反应体系,并采用最优检测体系对大口黑鲈样本进行检测验证。结果显示,在20μL检测体系中加入200 nmol/L Cas13a、100 nmol/L crRNA1、100 nmol/L crRNA2及500 nmol/L ssRNA报告探针,在37℃的情况下能够获得最佳的检测效果。并且该检测体系可以检测到102 fM的MSRV病毒,具有良好的特异性和灵敏性,此外检测结果可直接通过紫外灯照射直接观察。研究基于CRISPR/Cas13a系统结合等温扩增MIRA技术建立的MSRV检测方法,可在室温下且不需要昂贵的仪器进行MSRV病毒检测,检测结果可以肉眼直接观察,能在多种场合下使用,研究结果为检测MSRV提供了有效方法。

关键词：大口黑鲈弹状病毒 CRISPR-Cas13a MIRA 大口黑鲈