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Imaginary roots and weights for generalized Kac-Moody algebras

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Chinese Science Bulletin 1997年第15期42卷 1317-1318页

作者： Jin, YD Li, zh zhang, ZX Department of Fundamental Science North China Electric Power University Baoding China Department of Mathematics Hebei University Baoding China

THE symbols in this letter are the same as those of ref. [1] and we

关键词： root

Determination of the extragalactic-planetary frame tie from Earth orientation parameters

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Chinese Science Bulletin 1997年第4期42卷 315-318页

作者： Ping, JS Li, JL Jin, WJ Qian, zh Joint Radw Astronomy Research Laboratory Shanghai Observatory Chinese Academy of Sciences Shanghai China

PRLSENTLY there are three kinds of realization of conventional celestial reference frames (CCRFs), i. e. the optical frame, the planetary frame and the extragalactic radio frame. 'Though the CCRFs are high in precision, due to the difference in (ⅰ) the constants, parameters, formulae and force models used to define the frames; (ⅱ) the methods and techniques

关键词： earth orientation parameters (EOP) celestial reference frame tie.

Aequorin-Based Luminescence Imaging Reveals Stimulus-and Tissue-Specific Ca^2＋ Dynamics in Arabidonsis Plants

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Molecular Plant 2013年第2期6卷 444-455页

作者： Xiaohong zh Ying Feng Gaimei Liang Na Liu Jian-Kang zhua Department of Horticulture and Landscape Architecture Purdue University West Lafayette IN 47907 USA Shanghai Center for Plant Stress Biology and Shanghai Institute of Plant Physiology and Ecology Shanghai Institutes of Biological Sciences ChineseAcademy of Sciences Shanghai 200032 China

Calcium ion is a versatile second messenger for diverse cell signaling in response to developmental and environmental cues. The specificity of Ca^2＋-mediated signaling is defined by stimulus-elicited Ca^2＋ signature and down-stream decoding processes. Here, an Aequorin-based luminescence recording system was developed for monitoring Ca^2＋ in response to various stimuli in Arabidopsis. With the simple, highly sensitive, and robust Ca^2＋ recording, this system revealed stimulus-and tissue-specific Ca^2＋ signatures in seedlings. Cellular Ca^2＋ dynamics and relationship to Aequorin-based Ca^2＋ recording were explored using a GFP-based Ca^2＋ indicator, which suggested that a synchronous cellular Ca^2＋ signal is responsible for cold-induced Ca^2＋ response in seedlings, whereas asynchronous Ca^2＋ oscillation contributes to osmotic stress-induced Ca^2＋ increase in seedlings. The optimized recording system would be a powerful tool for the iden-tification and characterization of novel components in Ca^2＋ -mediated stress-signaling pathways,

关键词： Aequorin Case12 abiotic stress calcium Arabidopsis.

Comparison between hydrogen-transfer and fluoro-transfer reactions on the microcanonical unimolecular rate constants

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Chinese Journal of Chemistry 1995年第5期13卷 391-395页

作者： Feng, WL zhang, SW Wang, Y Wu, JN Li, zh BEIJING NORMAL UNIV DEPT CHEMBEIJING 100875PEOPLES R CHINA

The microcanonical rate constants for the hydrogen-transfer process of HCCF (reaction 7) and the fluoro-transfer process of FCCF (reaction 8) are carried out with tunneling correction and curvature correction. The results show that the tunneling effects and curvature effects on the rate constant of reaction 7 is quite different from that of reaction 8. The rate constants for different rotational states are also studied for these reactions.

关键词： microcanonical rate constant tunneling effect curvature correction

Integrated positron emission tomography and computed tomography in preoperative lymph node staging of non-small cell lung cancer

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Chinese Medical Journal 2014年第4期127卷 607-613页

作者： Xu N Jiao Y Fang WG Wang MZ zhu zh zhang YQ Department of General Internal Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences &amp Peking Union Medical College Beijing 100730 China Department of Respiratory Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences &amp Peking Union Medical College Beijing 100730 China Department of Nuclear Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences &amp Peking Union Medical College Beijing 100730 China

Background Integrated positron emission tomography and computed tomography （PET/CT） is increasingly used for the preoperative nodal staging of non-smail cell lung cancer （NSCLC）.The aim of this study was to evaluate the accuracy of PET/CT in comparison with CT in detection of nodal metastasis and preoperative nodal staging in patients with NSCLC,and to analyze the causes of the PET/CT false-negative and false-positive *** Consecutive patients with pathologically proven NSCLC who underwent staging using PET/CT from July 2008 to February 2012 were evaluated *** staging was pathologically confirmed on tissue specimens obtained at *** accuracy of PET/CT and CT in the assessment of intrathoracic nodal involvement was determined using histological results as the reference *** regression was used to define the causes of the false-negative and false-positive *** A total of 528 lymph node stations were evaluated in 101 *** nodes were positive for malignancy in 43 out of 101 patients （42.6%）,and 101 out of 528 nodal stations （19.2%）.PET/CT was significantly more accurate for nodal staging than *** sensitivity,specificity,positive and negative predictive values,and accuracy of PET/CT for detecting nodal metastasis were 51.5%,95.8%,74.3%,89.3%,and 87.3% and the corresponding data by CT were 45.5%,87.1%,45.5%,87.1%,and 79.2%,***/CT confers significantly higher specificity,positive predictive value,and accuracy than CT in detecting nodal ***-negative results by PET/CT are significantly associated with smaller lymph node size,whereas false-positive results are related to a combination of inflammatory disorders and larger lymph node *** PET/CT confers significantly higher accuracy than CT in nodal staging,and is more specific and accurate than CT in detecting nodal metastasis but has a low sensitivity and high false-negative rate.

关键词： positron emission tomography computed tomography non-small cell lung cancer preoperative lymph node staging

Sonar Image Processing System for an Autonomous Underwater Vehicle(AUV)

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High Technology Letters 1995年第1期1卷 71-75页

作者： Wen, X. Yuling, W. Weiqing, zh. Academia Sinica Beijing China

Sonar image processing system is an important intelligent system of Autonomous Un-derwater *** on TMS320C30 high speed DSP,it is used to realize sonar imagecompression and underwater object detections including obstacle recognition in real *** paper,the software and hardware designs of this system are introduced and the experi-mental results are given.

关键词： Autonomous underwater vehicle Sonar image processing Digital signal processor

Structure dependence of intramolecular photoinduced electron transfer in 9-aminoacridine benzoyl esters dyads linked by a polyether chain

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Chinese Science Bulletin 1997年第19期42卷 1619-1624页

作者： Li, SL Tian, HJ zhou, QF Li, zh Xu, HJ CHINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

ELECTRON transfer plays a crucial role in energy transformation of natural biological systemssuch as the photosynthetic process by which plants convert solar energy into chemical *** is achieved in photosynthesis by a series of electron transfers which occur after light is ab-sorbed. Among the various factors which influence the efficiency of electron transfer struc-tural effect is one of the important features to be considered. In recent years, numerous syn-thetic model dyads in which electron donor and electron acceptor are covalently linked by dif-ferent spacers have been designed and synthesized in an effort to understand how the

关键词： polyether donor-acceptor dyads intramnlecular photoinduced electron transfer.

Studies of Optical Nonlinearity Behaviors of Ultrafine PbS Particles in Perfluorocarboxylated Cation-exchanged Films

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High Technology Letters 1995年第1期1卷 102-104页

作者： Xiaowen, zh. Xueping, L. Yuan, L. Xurui, X. Songbin, zh. Zongju, X. Yinghua, Z. Academia Sinica Beijing China

Ultrafine PbS particles with different sizes have been prepared in perfluorocarboxylated cation-exchanged films. The variation of PbS particle size was clarified by absorption spectra and TEM graphs. Time-resolved optical Kerr effects were measured by femtosecond pump-probe techniques. Optical Kerr effect response time was estimated to be less than 165 fs. A third-order optical nonlinearity of χ(3)10-12 esu for PbS particles was obtained and it was found that it increases with the decrease of particle sizes, showing the influence of quantum confined effect on optical nonlinear behaviour of ultrafine particles.

关键词： PbS Ultrafine particle Optical nonlinearity Optical Kerr effect

Photoelectrochemical Behaviours of Tandem Semiconductive Electrode

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Chinese Chemical Letters 1997年第8期8卷 721-724页

作者： Jiang, DL Han, zh Song, YH Wang, QF Tong, RT Li, GC HEBEI TEACHERS UNIV DEPT CHEMHEBEI 050016PEOPLES R CHINA HEBEI CHEM ENGN INST HEBEI 050016PEOPLES R CHINA

The photoelectrochemical behaviour of the multilayer semiconductive electrode(GaAs/AlxGa1-xAs)with the structure of N+NP and N+NPP was studied in Na2SO4 solution. Compared with single kind semiconductor electrode, the commposite one has broader photoresponse spectral region and larger open-circuit photovoltage,consequently gives higher solar energy conversion efficiency.

关键词： CELLS SI