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Cell Research 2006年第10期16卷 830-840页

作者： Yan-Hong Chen~(1,2,3. Xue-Min Wu~5 Hong-Qing Ling~4 Wei-Cai Yang~1 ~1The key laboratory of Molecular and Developmental Biology,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Beijing 100101 china ~2Graduate {3. of the Chinese Academy of Sciences,19 Yuquan Road,Beijing 100049,china ~3.chool of Life Science,Nantong {3.,Nantong 226007 china ~4The state key laboratory of Plant Cell and Chromosome Engineering,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Beijing 100101,china ThekeylaboratoryofMolecularandDevelopmentalBiology InstituteofGeneticsandDevelopmentalBiologyChineseAcademyofSciencesBeijing100101China GraduateuniversityoftheChineseAcademyofSciences 19YuquanRoadBeijing100049

In plant,iron uptake and homeostasis are tightly regulated to ensure its absorption from soil and to avoid excessiron in the *** genes involved in this process have been identified during past several years,but there are manyproblems remain unsolved in the genetic regulation of whole plant iron trafficking and *** transcriptionfactors contain tandem repeats of a～50 amino acid DNA-binding motif (R) and are involved in the regulation of manyaspects of plant development,hormone signaling and ***,we report that the ectopic expression of orchidR2R3.MYB gene DwMYB2 in Arabidopsis thaliana confers the transgenic plants hypersensitivity to iron *** DwMYB2 transgenic plants,the iron content in root is two-fold higher compared to that in wild-type root,while thereverse is true in *** imbalance of iron content in root and shoot suggested that the translocation of iron fromroot to shoot was affected by the expression of DwMYB2 in the transgenic ***,gene chip and reversetranscription-polymerase chain reaction analysis revealed that the ferric-chelate reductase gene,AtFRO2,and the irontransporter gene,AtIRT1 and AtIRT2,are up-regulated by DwMYB2 expression,while other potential iron transporterssuch as AtIREG1,AtFRD3.and NRAMP1 are *** addition,the expression of several putative peptidetransporters and transcription factors are also altered in the 3.S::DwMYB2 transgenic *** data provide us insightinto the whole plant translocation of iron and identify candidate genes for iron homeostasis in plants despite the fact thata heterologous gene was expressed.

关键词： DwMYB2 iron uptake and homeostasis iron transporters Arabidopsis

Magnetic Semiconductors Based on New Versatile Ligands with Highly Delocalized Sulfur-rich Core

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Magnetic Semiconductors Based on New Versatile Ligands with ...

Mild Hydrothermal Synthesis, Characterization and Properties of Na_5Ce(PO_4)_3. Na_3.b_2(PO_4)_3.H_2O and Na_(5-2x)Yb_2xCe_(1-x)(PO_4)_3.yH_2O

全国第八届有机固体电子过程暨华人有机光电功能材料学术讨论会

作者： Jinglin Zuo~*,Xiaozeng You (Coordination Chemistry Institute and the state key laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering,{3. university,{3. 210093.

Owing to unique π electron-donating-properties,tetrathiafulvalene and its derivatives(TTFs) have been extensively studied for decades to build molecular conductors and sup erconductors M ore recently,the investigation of magnetic conductor and magnetic semiconductor based on TTFs has been receiving much attention,due to its potential application in spintronics.

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Chemical Research in Chinese Universities 2000年第4期16卷 287-300页

作者： XU Yao-hua, WANG Dan, FENG Shou-hua, PANG Wen-qin and YUE Yong (key laboratory of Inorganic Synthesis & Preparative Chemistry, Jilin university, Changchun 13.023. P. R.{3. Wuhan Institute of Physics, Academia Sinica, Wuhan 43.071, P. R.{3.) 吉林大学无机合成与制备化学开放实验室吉林长春 130023 中科院武汉物理与数学所湖北武汉 430071

Novel phosphates, Na5-2x Yb2xCe1-x (PO4)3.yH2O(x=0-1, y=0-1), were synthesized under mild hydrothermal conditions at 240℃ with Ce(SO4)2·H2O, Ce(SO4)2·2(NH4)2SO4· 4H2O, CeO2, Yb2O3. 85 % H3.O4 and NaOH as the starting materials. The products were sensitively influenced by the pH value of the systems and reaction temperature. Under an acidic condition, CePO4 was the product at 240℃, in which Ce(Ⅳ ) species was reduced to Ce(Ⅲ) species. Under a weak basic condition, Na2Ce(PO4)2·0. 79H2O was produced. Under a medium basic condition, the expected compound Na5Ce(PO4)3.was the product. Under a basic condition, CeO2 was the final product, amorphous phase was also produced in some cases. The structure of the compounds were investigated by X-ray diffraction, SEM, IR, Raman, 3.P MAS NMR and XPS spectroscopies. To determine the valence of Ce in the compound, EPR and DRS of the compound were also recorded. The thermal properties of the compounds were determined with DTA-TG analysis. Na5Ce(PO4)3.was decomposed into Na3.e(PO4)2, Na4P2O7 and O, at 694℃, in which Ce(Ⅳ) was reduced to Ce(Ⅲ) species. Na3.b2(PO4)3.H2O lost water and was transferred into a new phase at a high temperature 682℃. The thermal stability of Na5-2xYb2xCe1-x (PO4)3. yH2O could be improved by increasing x value. When x=0. 54, the compound was stable even at the temperature ca. 1 000℃.The ionic conductivities of the compounds were increased when the amount of Yb in the compound was increased and when x=0. 3., it reached the highest value (σ3.0℃= 3. 96 ×10-6 S·cm-1).

关键词： Cerium Ionic conduction Mild hydrothermal synthesis Rare earth phosphate Ytterbium

Statistical characteristics of the double ridges of subtropical high in the Northern Hemisphere

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Science Bulletin 2005年第20期 82-87页

作者： ZHAN Ruifen1,2,3. LI Jianping1 & HE Jinhai2 1. state key laboratory of Numerical Modeling for Atmospheric Sci- ences and Geophysical Fluid Dynamics (LASG), Institute of Atmos- pheric Physics, Chinese Academy of Sciences, Beijing 100029, {3. 2. Department of Atmospheric Sciences, Institute of Meteorology, Nan- jing university of Information Science and Technology, nanjing 210044,{3. 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003.,{3.

The generality and some climatological charac- teristics of the double ridge systems of subtropical high (SH) are investigated statistically by using the daily NCEP/NCAR reanalysis data from 1958 to 1998. The results show that the SH double-ridge event is a common phenomenon in the Northern Hemisphere, with the distinct seasonal and re- gional features, that is, the majority of SH double-ridge geneses concentrate over the eastern North India Ocean- western North Pacific as well as the central North Pacific in the period from mid-July to mid-September. Especially over the western North Pacific subtropics, the SH double-ridge events are extremely active. It is found that the life cycle of most double-ridge events of western Pacific subtropical high (WPSH) is shorter but some still last longer. The WPSH dou- ble-ridge events occur most frequently from July to Septem- ber, while there is a paucity of occurrences during Novem- ber-March. Also, it is shown that the WPSH double-ridge events have a strong interannual variation with a certain periodicity which possesses a remarkably abrupt change in the mid-1970s. Additionally, the relationship between the WPSH double ridges and the meridional movement of WPSH is discussed.

关键词： subtropical high double ridges statistical characteristics meridional movement.

Virtualities of quark and gluon in QCD vacuum

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1439-1447页

作者： ZHOU LiJuan1, QIN SongMei2, WU Qing3.& MA WeiXing4 1 Collaboration Group of Hadron Physics and Non-perturbative QCD Study, Guangxi university of Tech- nology, Liuzhou 545006, china 2 Department of Physics, Guangxi university, Nanning 540003. china 3.Department of Physics, Qingdao university, Qingdao 266071, china 4 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, china 1. Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China 2. Department of Physics Guangxi University Nanning 540003 China 3. Department of Physics Qingdao University Qingdao 266071 China 4. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The non-local vacuum condensates of quantum chromodynamics (QCD) describe the distributions of quarks and gluons in the non-perturbative QCD vacuum state. Physically, this means that vacuum quarks and gluons have a nonzero mean-squared momentum in the vacuum, called virtuality. The quark virtuality is given by the ratio of the local quark-gluon mixed vacuum condensate to the quark local vacuum condensate. The gluon virtuality is expressed by gluon vacuum condensates and four-quark vacuum condensates. We study the two virtualities by solving Dyson-Schwinger Equations and calculating quark and gluon vacuum condensates. Our theoretical results for quark virtuality are in good agreement with many other theoretical model predictions such as QCD sum rules and lattice QCD calculations. Our calculation on gluon virtuality is initial and the results are quite interesting.

关键词： quark gluon virtuality QCD vacuum condensate non-perturbative QCD

Stability and L2 — L∞ Analysis for A Class of Interconnected Systems

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Stability and L2 — L∞ Analysis for A Class of Interconnect...

Enhancement in Activity of a Vanadium Catalyst for the Oxidation of Sulfur Dioxide by Radio Frequency Plasma During the Preparation Process

2011 Chinese Control and Decision Conference（CCDC）

作者： Yongmin Li,Shumin Fei are with key laboratory of Measurement and Control of Complex Systems of Engineering,Ministry of Education,School of Automation,southeast {3.,nanjing,210096,Jiangsu,china.Yuming Chu and Zhenjiang Zhao are with School of Science,Huzhou Teachers College,Huzhou,3.3.00,Zhejiang,china.

This paper deals with the problem of stochastically stability and L2—L∞ performance analysis for a class of interconnected Markovian jump filtering error system with constant time *** using mode-dependent decentralized filters and constructing mode-dependent centralized Lyapunov functional together with Jensen’s inequality,the stability conditions for the filtering error system are presented which also ensures the L2—L∞ *** obtained stability conditions are delay-dependent which may be less conserve than that delay independent one,especially when time-delay are very ***,these conditions are expressed in terms of matrix inequalities （LMIs）,which may provide the convenience for the design of the concerned filters through linear matrix inequality technique.

关键词： Interconnected Markovian jump systems Decentralized filters Stochastic stability L2—L∞ performance Time delays

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Journal of Natural Gas Chemistry 2003年第3期12卷 195-200页

作者： Zhenxing Chen, Honggui Li, Lingsen Wangstate key laboratory for Powder Metallurgy, College of Chemistry and Chemical Engineering, Central South {3., Changsha 410083. china state key laboratory for Powder Metallurgy College of Chemistry and Chemical Engineering Central South University

Radio frequency plasma was used to prepare a vanadium catalyst. The resultsshowed that activating time of the catalyst could be shortened quickly and the catalytic activitywas improved to some extent with the use of plasma. Catalyst Ls-9 was prepared under an optimalcondition of 40 W discharge power, 10 min discharge time and 8 Pa gas pressure. The catalyticactivity was up to 54.7% at 410℃, which was 2.2% higher than that of the Ls-8 catalyst. Only 10 minwas needed to activate the catalyst with plasma, which was 1/9 of the traditional calcination *** Ls-9, both the endothermic as well as the exothermic peaks detected by differential thermalanalysis shifted to higher temperatures obviously, indicating that its crystal phase could melteasily. There existed an apparent endothermic peak at 283.. SEM photographs showed a uniform sizedistribution. It is inferred that the quadrivalent vanadium compound may exist mainly in the form ofVOSO_4.

关键词： plasma activation dispersion vanadium catalyst low-temperature activity

Phosphorus forms and distribution in the sediments of Poyang Lake,china

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International Journal of Sediment Research 2011年第2期26卷 230-238页

作者： XIANG Su-lin and ZHOU Wen-bin 1 Lecturer,key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,Nanchang university,Nanchang 3.0047,china and Department of Environmental Engineering,East{3. JiaoTong university,Nanchang 3.0013.china, 2 Prof,key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,Nanchang university,Nanchang 3.0047,china [a]Lecturer Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China and Department of Environmental Engineering East China JiaoTong University Nanchang 330013 China [b]Prof. Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China

The forms and distribution of phosphorus in the sediments of Poyang Lake were studied using chemical extraction methods to understand the potential release and adsorption of *** results showed that phosphorus in the sediments mainly consisted of inorganic phosphorous species, including iron bound phosphorus,calcium bound phosphorus,aluminium bound phosphorus and dissolved phosphorus,as well as organic phosphorous *** spatial distribution of phosphorus species in surface sediments showed a decreasing trend from the outlet to the entrance of Poyang *** content of total phosphorus in the surface sediments ranged from 688.29 to 825.3. mg/kg, and inorganic phosphorous was the major phosphorus *** bound phosphorus was the dominant form of inorganic phosphorous,accounting for greater than 40%of the total phosphorus, while calcium bound phosphorus and aluminium bound phosphorus accounted for more than 20%, and dissolved phosphorus accounted for less than 5%.The content of organic phosphorus in surface sediments was lower,accounting for less than 15%.Total phosphorus was positively correlated with iron bound phosphorus,aluminium bound phosphorus,calcium bound phosphorus and organic phosphorous,while organic phosphorous was positively correlated with iron bound phosphorus and aluminium bound phosphorus,but only weakly related to calcium bound *** all six sites, the contents of total phosphorus and phosphorus forms in the core sediments obviously decreased with depth,while they were significantly enriched in the surface *** total phosphorus and phosphorus forms contents were significantly higher in the upper layers and had a tendency to decrease toward the bottom of the core,regardless of the phosphorus *** addition,the average contents of total phosphorus and various phosphorus forms decreased rapidly with sediment depth from 0-20 cm,and then decreased slightly from 20-3. cm.

关键词： Poyang Lake Phosphorus forms Distribution characteristics Sediment

Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi Corridor, NW china Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANCongrong LIUJinfeng ZHANGJunyan keylaboratoryofWesternEnvironmentalChanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 13. kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern china, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3.( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 kyr^113.3.kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern china. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern china