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Chinese Science Bulletin 2001年第15期46卷 1242-1251页

作者： Shuhua Ma Xiaodong zhang Hong Xu Xingkang zhang qiyuan zhang State Key Laboratory for Structural Chemistry of Unstable & Stable Species Center of Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing China

The semiempirical AMI method, ah initio (HF/3-21G, 6-31G, 6-31G(d), 6-31+G(d)) and DFT (B3LYP/6-31G(d), 6-31+G(d)) methods were used to optimize the geometry of DDQ and its anion radical DDQ-. Nelsen’s model was used to calculate the internal reorganization energy λi of self-exchange electron transfer (ET) reactions. The calculated λi results of DDQ/DDQ-. by AM1 and B3LYP/ 6-31G(d), 6-31+G(d) methods are close to each other and consistent with the reported values; while those from Har-tree-Fock methods are too large because of not consideringthe effect of electron correlation. The structure and ET behavior of MQ0 /MQ0- couple were studied by AM1 and DFT (B3LYP/6-31G(d), 6-31+ G(d, p)) methods, and those of MQ0 /MQn-(n=1-7) were studied by AM1 method for the first time. The results indicate that the values of the heat of formation of MQn increases with the increasing of the length of the isoamylene substituent chains. It also shows that the length of substituent has little effect on the bond lengths,

关键词： DDQ menaquinone (MQn) self-exchange electron transfer internal reorganization energy AM1 ab initio DFT.

Evidence of ancient rock-ice avalanches along the China-Bhutan Chomolhari Range,and their implications for demise of the summit

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Journal of Mountain Science 2024年第9期21卷 2876-2890页

作者： HU Kaiheng zhang qiyuan LI Pu zhang Xiaopeng LIU Shuang LI Hao Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of Chinese Academy of Sciences Beijing 100149China

Large-scale rock-ice avalanches resulting from the interaction of tectonics and climate are characterized with high mobility,huge volumes of sediment,and rapid denudation,being a major agent of landscape evolution in high altitude mountainous ***,the extreme glaciated slope failures often transform into extraordinarily large and mobile debris flows,resulting in disastrous consequences such as sedimentation and *** to a dearth of on-site observation data and experimental data collection,our comprehension of the geomorphic and kinematic characteristics of rock-ice avalanches remains *** we report a cluster of ancient rock-ice avalanches spreading along the Chomolhari range of the China-Bhutan *** integrating remote sensing image interpretation with detailed field investigations,we demonstrate the geomorphic and sedimentary characteristics of four events among the *** estimated volumes of the four are 23.73 Mm³,39.69 Mm³,38.43 Mm³,and 38.25 Mm³,*** presence of pre-existing moraines or alluvial fans constrained their movement,resulting in deposition features such as marginal digitated lobes at higher elevations and large depressed areas in the *** the Savage-Hutter theory,we calculate the basal friction angle and travel angle of these ancient rock-ice avalanches that are both less than 10°,affirming the similarity of these avalanches in the study area to those occurring in other *** study significantly contributes to understanding the geomorphic and kinematic characteristics of rock-ice avalanches in high-altitude mountainous regions,providing valuable insights into their response to the disproportionate growth of Himalayan peaks.

关键词： Rock-ice avalanche Himalayas Southern Yadong-Gulu rift Vertical slip-rate Landscape evolution

Observable-specific phase biases of Wuhan multi-GNSS experiment analysis center’s rapid satellite products

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Satellite Navigation 2022年第3期3卷 91-105,I0003页

作者： Jianghui Geng qiyuan zhang Guangcai Li Jingnan Liu Donglie Liu GNSS Research Center Wuhan University129 Luoyu RoadWuhan430079China Hubei Luojia Laboratory Wuhan University129 Luoyu RoadWuhan430079China Natural Resources Satellite Remote Sensing Application Center 242 Zhonghuabei RoadGuiyang550004China

Precise Point Positioning(PPP)with Ambiguity Resolution(AR)is an important high-precision positioning technique that is gaining popularity in geodetic and geophysical *** implementation of PPP-AR requires precise products such as orbits,clocks,code,and phase *** one of the analysis centers of the International Global Navigation Satellite System(GNSS)Service(IGS),the Wuhan University Multi-GNSS experiment(WUM)Analysis Center(AC)has provided multi-GNSS Observable-Specific Bias(OSB)products with the associated orbit and clock *** this article,we first introduce the models and generation strategies of WUM rapid phase clock/bias products and orbit-related products(with a latency of less than 16 h).Then,we assess the performance of these products by comparing them with those of other ACs and by testing the PPP-AR positioning precision,using data from Day of the Year(DOY)047 to DOY 078 in *** is found that the peak-to-peak value of phase OSBs is within 2 ns,and their fluctuations are caused by the clock day boundary *** associated Global Positioning System(GPS)orbits have the best consistency with European Space Agency(ESA)products,and those of other systems rank in the medium *** NAvigation Satellite System(GLONASS)clocks show slightly inconsistency with other ACs’due to the antenna thrust power adopted,while the phase clocks of other GNSSs show no distortion compared with legacy *** well-estimated phase products for Precise Orbit Determination(POD),the intrinsic precision is improved by 14%,17%,and 24%for GPS,Galileo navigation satellite system(Galileo),and BeiDou-3 Navigation Satellite System(BDS-3),*** root mean square of PPP-AR using our products in static mode with respect to IGS weekly solutions can reach 0.16 cm,0.16 cm,and 0.44 cm in the east,north,and up directions,*** multi-GNSS wide-lane ambiguity fixing rates are all above 90%,while the narrow-lane fixing rates above 80%.

关键词： Multi global navigation satellite system Observable-specific phase bias Precise point positioning with ambiguity resolution Wuhan University multi-GNSS experiment analysis center Precise orbit determination

Improving analytic hierarchy process applied to fire risk analysis of public building

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Chinese Science Bulletin 2009年第8期54卷 1442-1450页

作者： SHI Long zhang RuiFang XIE qiyuan FU LiHua State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230027 China

The structure importance in Fault Tree Analysis(FTA) reflects how important Basic Events are to Top *** at alternative level in Analytic Hierarchy Process(AHP) also reflect its importance to general *** on the coherence of these two methods,an improved AHP is put *** this improved method,how important the attribute is to the fire safety of public building can be analyzed more credibly because of the reduction of subjective *** venues are very important public buildings in *** fire safety evaluation of them will be a big issue to *** AHP is a useful tool to the safety evaluation to these Olympic venues,and it will guide the evaluation in other areas.

关键词：改进层次分析法公共建筑风险分析消防安全评价火灾奥运场馆故障树分析安全性评价

Spectroscopic investigation on the telomeric DNA base sequence repeat

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Chinese Science Bulletin 2002年第2期47卷 108-111页

作者： Sichuan Xu Xicheng Ai Zhaoyong Sun qiyuan zhang Xingkang zhang Chinese Acad Sci Inst Chem State Key Lab Struct Chem Unstable & Stable Speci Ctr Mol Sci Beijing 100080 Peoples R China

Telomeres are protein-DNA complexes at the terminals of linear chromosomes, which protect chromoso-mal integrity and maintain cellular replicative capacity. From single-cell organisms to advanced animals and plants, structures and functions of telomeres are both very conser-vative. In cells of human and vertebral animals, telomeric DNA base sequences all are (TTAGGG)n. In the present work, we have obtained absorption and fluorescence spectra measured from seven synthesized oligonucleotides to simu-late the telomeric DNA system and calculated their relative fluorescence quantum yields on which not only telomeric DNA characteristics are predicted but also possibly the shortened telomeric sequences during cell division are im-plied. Oligonucleotide 5’- TTAGGGTTAGGG holds a low relative fluorescence quantum yield and remarkable excitation energy innerconversion, which tallies with the telomeric sequence of (TTAGGG)n. This result shows that telomeric DNA has a strong non-radiative or innerconvertible capabil-

关键词： DNA telomere oligonucleotide fluorescence quantum yield.

Excitation energy distribution between two photosystems in Porphyra yezoensis and its significance in photosynthesis evolution

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Chinese Science Bulletin 2001年第1期46卷 49-52页

作者： PAN Jie SHI Dingji CHEN Jianxin PENG Guohong ZENG Chengkui zhang qiyuan State Key Laboratory for the Structure of Unstable and Stable Species Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100080China Photosynthesis Research Center Institute of BotanyChinese Academy of SciencesBeijing 100093China Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Comparative investigation on energy distribution between two photosystems were carried out in the sporo-phytes and gametophytes of Porphyra yezoensis. By performing 77 K fluorescence spectra, we suggested that there probably existed a pathway for energy transfer from PS II to PS I to redistribute the absorbed energy in gametophytes, while no such a way or at minor level in sporophytes. Electron transfer inhibitor DCMU blocked the energy transfer from PS II to PS I in gametophytes, but no obvious effects on sporophytes. These indicated that excitation energy distribution between two photosystems in gametophytes was more cooperative than that in sporophytes. These data in ontogenesis reflected the evolution process of photosynthetic organisms and supported the hypothesis of independent evolution of each photosystem.

关键词： evolution of photosystems excitation energy distribution Porphyra yezoensis sporophyte and gametophyte.

THERMODYNAMIC ANALYSES FOR S-H_2O SYSTEM AT 25℃

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中国有色金属学会会刊：英文版 1997年第1期7卷 28-33页

作者： Yi Qingfeng, Chen qiyuan, zhang Hengzhong, zhang Pingmin Dept. of Chemistry, Central South University of Technology, Changsha 410083

ＴＨＥＲＭＯＤＹＮＡＭＩＣＡＮＡＬＹＳＥＳＦＯＲＳＨ２ＯＳＹＳＴＥＭＡＴ２５℃①ＹｉＱｉｎｇｆｅｎｇ，ＣｈｅｎＱｉｙｕａｎ，ＺｈａｎｇＨｅｎｇｚｈｏｎｇ，ＺｈａｎｇＰｉｎｇｍｉｎＤｅｐｔ．ｏｆＣｈｅｍｉｓｔｒｙ，Ｃ... 详细信息

ＴＨＥＲＭＯＤＹＮＡＭＩＣＡＮＡＬＹＳＥＳＦＯＲＳＨ２ＯＳＹＳＴＥＭＡＴ２５℃①ＹｉＱｉｎｇｆｅｎｇ，ＣｈｅｎＱｉｙｕａｎ，ＺｈａｎｇＨｅｎｇｚｈｏｎｇ，ＺｈａｎｇＰｉｎｇｍｉｎＤｅｐｔ．ｏｆＣｈｅｍｉｓｔｒｙ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒ...

关键词： potential pH diagram thermodynamics S H 2O system sulfur

An alternative strategy for Triple-frequency Multi-GNSS cycle-slip detection

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An alternative strategy for Triple-frequency Multi-GNSS cycl...

电子游戏与民间传统的跨媒介转化——以FGO及其玩家实践为个案

第九届中国卫星导航学术年会

作者： qiyuan zhang Jiang Guo GNSS Center of Wuhan University

Future GNSS constellation will contain more than 120 satellites,and the number of frequency bands are gradually ***-constellation GNSS positioning has shown a broad development *** order to meet the increasing demand of multi-frequency multi-constellation,this paper presents a data pre-processing scheme,which is used to detect cycle slips of triple-frequency multi-constellation *** method is integrating triple-frequency ionosphere-free observations,dual-frequency G-F observations and dual-frequency M-W observations to detect cycle slips with Turbo Edit *** specific detection method is polynomial fitting,which weaken the noise level of the observation and improve the efficiency of *** combination coefficient of the triple-frequency ionosphere-free observation is deduced from the least-squares *** triple-frequency detection method is established while the traditional dual-band detection capability still remains,to meet the needs of both dual-frequency users and triple-frequency *** experimental results show that this method is able to detect the obvious cycle slips,and improve the quality of the observed data.

关键词： cycle slips Turbo Edit triple-frequency ionosphere-free combination

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文化遗产 2024年第1期 122-129页

作者：张淇源北京师范大学文学院民间文学研究所北京100875

媒介技术的发展使民间传统在电子游戏中不断地被重构,本文以FGO这一二次元抽卡游戏及其玩家实践为研究对象,着力探究了游戏剧情对民间传统的吸纳以及游戏玩家对相关转化的接受。游戏玩家与创编者之间的互动,共同界定了改编的限度,即尊... 详细信息

媒介技术的发展使民间传统在电子游戏中不断地被重构,本文以FGO这一二次元抽卡游戏及其玩家实践为研究对象,着力探究了游戏剧情对民间传统的吸纳以及游戏玩家对相关转化的接受。游戏玩家与创编者之间的互动,共同界定了改编的限度,即尊重文化主体对传统的审美期待。最后,文本内部/文本外部,形式/内核是研究者考察民间传统如何创编的重要理路。

关键词：电子游戏 FGO 民间传统跨媒介玩家

Genetic Diversity of Blastocystis in Kindergarten Children in Southern Xinjiang,China

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Genetic Diversity of Blastocystis in Kindergarten Children i...