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The Mixed LB film of Crowned Phthalocyanine and Picrate

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chinese Chemical Letters 1998年第6期9卷 573-575页

作者： Xi You li Hui Jun XU(Institute of Photographic Chendstry, chinese academy of sciences, beijing 100101) Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

The mixed LB film of mono crown ether substituted phthalocyanine (CPc) and potassium picrate (PiK) were prepared by adding potassium picrate in subphase. The pi-A isotherms show that the addition of PiK in subphase increases the orientation angles of phthalocyanine in monolayers. The absorption spectra revealed that the monolayer can be transferred to substrates easily. X-ray diffraction results show that the mixed film possesses the same thickness as that of pure phthalocyanine film.

关键词： mono crown ether phthalocyanine LB film picrate

Pulsars in FIRST Observations

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 146-150页

作者： Xiang-Hua li and Jin-lin Han National Astronomical Observatories, chinese academy of sciences, beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We identify 16 pulsars from the Survey of Faint Images of the Radio Sky at Twenty-cm (FIRST) at 1.4 GHz. Their positions and total flux densities are extracted from the FIRST catalog. By comparing the source positions with those in the PSR catalog, we obtain better determined positions of PSR J1022+1001, J1518+4904, J1652+2651, and proper motion upper limits of PSR J0751+1807, J1012+5307, and J1640+2224. The proper motions of the other ten pulsars are consistent with the catalog values.

关键词： pulsar: general -stars: neutron

Period-doubling bifurcations of the thermocapillary convection in a floating half zone

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1681-1686页

作者： AA Yan,li Kai,TANG ZeMei,CAO ZhongHua & HU WenRui National Microgravity Laboratory,Institute of Mechanics,chinese academy of sciences,beijing 100190,china National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing China

This study experimentally explored the fine structures of the successive period-doubling bifurcations of the time-dependent thermocapillary convection in a floating half zone of 10 cSt silicone oil with the diameter d0=3.00 mm and the aspect ratio A=l/d0=0.72 in terrestrial *** onset of time-dependent thermocapillary convection predominated in this experimental configuration and its subsequent evolution were experimentally detected through the local temperature *** experimental results revealed a sequence of period-doubling bifurcations of the time-dependent thermocapillary convection,similar in some way to one of the routes to chaos for buoyant natural *** critical frequencies and the corresponding fractal frequencies were extracted through the real-time analysis of the frequency spectra by Fast-Fourier-Transfor-mation(FFT).The projections of the trajectory onto the reconstructed phase-space were also ***,the experimentally predicted Feigenbaum constants were quite close to the theoretical asymptotic value of 4.669 [Feigenbaum M *** Lett A,1979,74:375-378].

关键词： thermocapillary convection bifurcation transition to turbulence

Numerical simulation of the sensitivity of the Pacific subtropical-tropical meridional cell to global warming

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Progress in Natural Science:Materials International 2006年第5期16卷 507-511页

作者： ZHOU Tianjun, YU Yongqiang, liU Hailong, li Wei and YU Rucong (LASG, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china) LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Sensitivity of the Pacific subtropical-tropical meridional cell to global warming is examined by using a global ocean-atmosphere coupled model developed at LASG/IAP. Results indicate that associated with the increasing of atmospheric carbon dioxide, the most prominent signals of global warming locate at high latitudes, and the change of middle and low latitudes, in particular the surface wind, is relatively weak, which leads to a weak response of the Pacific subtropical-tropical meridional cell. At the time of atmospheric carbon dioxide doubling, the change of the meridional cell strength is smaller than the amplitude of natural variability.

关键词： Pacific subtropical-tropical meridional cell global warming ocean-atmosphere coupled model.

Typical basin-fill sequences and basin migration in Yanshan, North china ——Response to Mesozoic tectonic transition

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Science china Earth sciences 2004年第2期47卷 181-192页

作者： li Zhong, liU Shaofeng, ZHANG Jinfang & WANG Qingchen1. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2. china University of Geosciences, beijing 100083, chinaCorrespondence should be addressed to li Zhong (email: lizhongd@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China china University of Geosciences Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North china may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

LAZY4 acts additively with the starch-statolithdependent gravity-sensing pathway to regulate shoot gravitropism and tiller angle in rice

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Plant Communications 2024年第10期5卷 154-165页

作者： Wenguang Wang linzhou Huang Yuqi Song Songtao Gui Jiajia Cao Han Zhang Mengchen Du Jiaze Chen Zihao Wang Jie Zhou Xiangbing Meng Dali Zeng jiayang li Yonghong Wang National Key Laboratory of Wheat Improvement College of Life SciencesShandong Agricultural UniversityTai’an 271018China Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100039China Yazhouwan National Laboratory Sanya 572024China College of Advanced Agricultural sciences Zhejiang A&F UniversityHangzhou 311300China

Rice tiller angle is a key agronomic trait that has significant effects on the establishment of a high-yield rice ***,the molecular mechanism underlying the control of rice tiller angle remains to be clar***,we characterized the novel tiller-angle gene LAZY4(LA4)in rice through map-based ***4 encodes a C3H2C3-type RING zinc-finger E3 ligase localized in the nucleus,and an in vitro ubiquitination assay revealed that the conserved RING finger domain is essential for its E3 ligase *** found that expression of LA4 can be induced by gravistimulation and that loss of LA4 function leads to defective shoot gravitropism caused by impaired asymmetric auxin redistribution upon *** analysis demonstrated that LA4 acts in a distinct pathway from the starch biosynthesis regulators LA2 and LA3,which function in the starch-statolith-dependent *** genetic analysis showed that LA4 regulates shoot gravitropism and tiller angle by acting upstream of LA1 to mediate lateral auxin transport upon *** studies reveal that LA4 regulates shoot gravitropism and tiller angle upstream of LA1 through a novel pathway independent of the LA2-LA3-mediated gravity-sensing mechanism,providing new insights into the rice tiller-angle regulatory network.

关键词： auxin shoot gravitropism tiller angle LAZY4 rice

Elemental sulfur effects on Pb and Zn uptake by Indian mustard and winter wheat

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Journal of Environmental sciences 2003年第6期15卷 836-840页

作者： CUI Yan-shan, WANG Qing-ren , DONG Yi-ting, li Hai-feng (Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china. Research Center for Eco-Environmental sciences Chinese Academy of Sciences 北京 100085

A pot experiment was conducted to investigate the influence of elemental sulfur to contaminated soil on plant uptake by a heavy metal hyperaccumulator, Indian mustard(Brassica juncea) and a field crop, winter wheat(***). Elemental sulfur(S) with different rates was carried out, they were 0(S 0), 20(S 20), 40(S 40), 80(S 80), and 160(S 160) mmol/kg respectively. Extra pots with the same rates of S but without plants were used for soil sampling to monitor pH and CaCl 2-extractable heavy metal changes. The results showed that S enhanced phytoextraction of Pb and Zn from contaminated soil. Application S effectively decreased soil pH down to 1.1 as the most at the rate of S 160. The concentrations of CaCl 2-extractable Pb and Zn in soil and uptake of Pb and Zn by the plants were increased with soil pH decreased. A good correlation between CaCl 2-extractable Pb/Zn and soil pH was found(R 2 Pb = 0.847 and R 2 Zn = 0.991, n=25). With S application, soil CaCl 2-extractable Pb and Zn concentrations, concentration of Pb and Zn in plants and the amount of removal by plant uptake were significantly higher than those without S. Under the treatment of S 160, the highest CaCl 2-extractable Pb and Zn were observed, they were 4.23 mg/kg and 0.40 mg/kg, 2.7 and 2.0 times as that of the control(S 0) respectively. At the highest rates of S(S 160), both Indian mustard and winter wheat reached the highest uptake of Pb and Zn. The highest Pb concentrations in wheat and Indian mustard were 32.8 mg/kg and 537.0 mg/kg, all 1.8 times as that of the control, and the highest Zn concentrations in wheat and Indian mustard were 215.5 mg/kg and 404.0 mg/kg, 2.4 and 2.0 times as that of the control respectively. The highest removals of Pb and Zn from the contaminated soil were 0.41 mg/pot and 0.31 mg/pot by Indian mustard in the treatment of S 160 through 50 days growth.

关键词： elemental sulfur Pb Zn uptake contaminated soil

A COMPREHENSIVE DEA APPROACH FOR THE RESOURCE ALLOCATION PROBLEM BASED ON SCALE ECONOMIES CLASSIFICATION

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Journal of Systems Science & Complexity 2008年第4期21卷 540-557页

作者： Xiaoya li Jinchuan CUI Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China.

This paper is concerned with the resource allocation problem based on data envelopment analysis （DEA） which is generally found in practice such as in public services and in production process. In management context, the resource allocation has to achieve the effective-efficient-equality aim and tries to balance the different desires of two management layers： central manager and each sector. In mathematical programming context, to solve the resource allocation asks for introducing many optimization techniques such as multiple-objective programming and goal programming. We construct an algorithm framework by using comprehensive DEA tools including CCR, BCC models, inverse DEA model, the most compromising common weights analysis model, and extra resource allocation algorithm. Returns to scale characteristic is put major place for analyzing DMUs＇ scale economies and used to select DMU candidates before resource allocation. By combining extra resource allocation algorithm with scale economies target, we propose a resource allocation solution, which can achieve the effective-efficient-equality target and also provide information for future resource allocation. Many numerical examples are discussed in this paper, which also verify our work.

关键词： Common weights analysis (CWA) date envelopment analysis (DEA) decision making unit (DMU) efficiency score inverse DEA model multiple-objective linear programming (MOLP) resource allocation problem returns to scale (RTS).

Bifurcation and Chaos in a Weakly Nonlinear System Subjected to Combined Parametric and External Excitation

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Acta Mathematicae Applicatae Sinica 2002年第3期18卷 501-512页

作者： Wei li, Peng-cheng XuInstitute of Mathematics, beijing University of Chemical Technology, beijing 100029, chinaInstitute of Applied Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china Institute of Mathematics Beijing University of Chemical Technology Beijing China Institute of Applied Mathematics Academy of Mathematics and System Sciences Chinese Academy of Science Beijing China

In this paper the dynamics of a weakly nonlinear system subjected to combined parametric and external excitation are discussed. The existence of transversal homoclinic orbits resulting in chaotic dynamics and bifurcation are established by using the averaging method and Melnikov method. Numerical simulations are also provided to demonstrate the theoretical analysis.

关键词： Bifurcation chaos transversal homoclinic orbit