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The pointwise dimension of self-similar measures

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Chinese Science Bulletin 1999年第23期44卷 2136-2140页

作者： CHEN Ercai and XIONG Jincheng department of Mathematics , Nanjing normal {2. , Nanjing 2.0097, china department of Mathematics , South china normal {2., Guangzhou 510631 , china department of Mathematics Nanjing Normal University Nanjing China department of Mathematics South China Normal University Guangzhou China

The problem about the existence of pointwise dimension of self-similar measure has been discussed. The Hausdorff dimension of the set of those points for which the pointwise dimension does not exist equals the dimenti... 详细信息

关键词： self-similar measure point wise dimension Hausdorff dimension multifractal symbolic space.

From discrete [Mn_4] cluster to 1D complex: Two new mixed-valence manganese complexes with slow magnetization relaxation

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Science china chemistry 2009年第9期52卷 1463-1469页

作者： YANG PeiPei & LI LiCun department of chemistry, Nankai {2., Tianjin 300071, china department of chemistry Nankai University Tianjin 300071 China

A tetranuclear manganese complex [Mn4(HL)4(MeOH)4(SCN)2.·3MeOH (1) and a one-dimensional assembly of [Mn4] units, [Mn4(HL)4(MeOH)4(N(CN)2.2.·2.5MeOH (2. (H3L = 2.6-bis(hydroxymethyl)-4-methyl-phenol), have been synthesized and studied. Complexes 1 and 2.crystallize in the triclinic space group P 1and monoclinic space group P2./n, respectively. Complex 1 possesses a mixed-valence tetranuclear dicubane unit, which comprises two MnⅡ and two MnⅢ ions. Complex 2.is built from the similar tetranuclear [Mn4] units connected through two N(CN)2.anions into a 1-D chain. The temperature dependence of the magnetic susceptibilities of 1 and 2.indicates ferromagnetic interactions between the manganese ions. Frequency-dependent out-of-phase signals of alternating current magnetic susceptibilities are observed in the low temperature range for both complexes, indicating a slow magnetic relaxation.

关键词： tetranuclear manganese complex 1D complex magnetic properties slow magnetic relaxation

Supramolecularly assembled water layers stabilized by sebacic anions in complexes of Zn(II) and Co(II)

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Science china chemistry 2010年第12期53卷 2539-2546页

作者： XIAN HuiDuo,LIU JianFeng & ZHAO GuoLiang Zhejiang Key Laboratory for Reactive chemistry on Solid Surfaces Institute of Physical chemistry,Zhejiang {2. university College of chemistry and Life Science,Zhejiang {2. university,Jinhua 32.004,china 1. Zhejiang Key Laboratory for Reactive chemistry on Solid Surfaces Institute of Physical chemistry Zhejiang Normal University Jinhua 321004 China2. College of Chemistry and Life Science Zhejiang Normal University Jinhua 321004 China

Two three-dimensional supramolecular water architectures,[Zn(phen)3]2.·[Zn(C10H16O4)·(H2.)3]·(C10H16O4)2.2.H2.(1) and [Co(phen)3]2.·[Co(H2.)6]·(C10H16O4)3·30H2.(2.[phen=1,10-Phenanthroline,C10H16O4=sebacic dianion],have been synthesized and characterized by IR,elemental analysis,thermogravimetric analysis,and single-crystal X-ray *** two structures both contain extensive hydrogen bonding between water molecules as well as between water molecules and sebacic *** water molecules and sebacic acid O atoms assembled 2. supramolecular corrugated sheets with different morphology in the two complexes.

关键词： Zn(II) Co(II) complex sebacic acid crystal structure supramolecular self-assemble water cluster

Discrete Conley index and bifurcation points

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Journal of Shanghai university(English Edition) 2010年第6期14卷 400-404页

作者：王凯华傅新楚 department of Mathematics College of SciencesShanghai University College of Mathematics and Statistics Hainan Normal University

In this paper, a sufficient condition for the existence of bifurcation points for discrete dynamical systems is presented. The relation between two families of systems is further discussed, and a sufficient condition ... 详细信息

关键词： discrete dynamical system prime isolated invariant set extreme maximal isolated invariant set Conley index bifurcation point

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, china 2. department of Urban and Resources Sciences, Nanjing {2., Nanjing 2.0093, china 3. department of Earth Sciences, Nanjing {2., Nanjing 2.0093, china 4. department of Geography, Shaanxi normal {2., Xi’an 710062. china 5. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., china 6 department of Geography, Qinghai normal {2., Xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. department of Earth Sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Kinetics and mechanism of the reaction between thiourea and iodate in unbuffered medium

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Science china chemistry 2004年第6期47卷 480-487页

作者： WANG Shun1,2. LIN Juanjuan1, CHEN Fan1, HU Maolin1, HU Xingen1, HAN Yiping1 & GAO Qingyu2.1.department of chemistry and Material Science, Wenzhou {2. College, Wenzhou 32.02., china 2. College of Chemical Engineering, china university of Mining and Technology, Xuzhou 2.1008, china 1. department of chemistry and Material Science Wenzhou Normal College 325027 Wenzhou China 2. College of Chemical Engineering China University of Mining and Technology 221008 Xuzhou China

The reaction between iodate and thiourea has been studied in an unbuffered acidic medium. In excess iodate the reaction shows not only oligooscillations in pH, Pt potential and the concentration of iodide ion, [I?], but also an initial induction period which has the linear relation with initial pH. At the end of the induction period, [I?] decreases sharply and a yellow coloration (due to iodine) appears transiently. While in excess thiourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at the end of the reaction. The induction period from the start of the reaction to the maximum of [I2. is also directly proportional to initial pH. A 14-step mechanism, including a H+-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using this mechanism give good agreement with experiments.

关键词： oligooscillations, pH dynamics, thiourea, iodate, complex reaction mechanism, dynamic simulation.

CONTINUITY AND LINEARITY OF ADDITIVE DERIVATIONS OF NEST ALGEBRAS ON BANACH SPACES

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 227-236页

作者： HAN DEGUANG department of Mathematics, Qufa normal {2., Qufu 2.3165, Shandong, china. QUFA normal UNIV DEPT MATHQUFU 273165SHANDONGPEOPLES R CHINA

This paper discusses the problem concerning the continuity and linearity of additive derivation of nest algebras on normed spaces. It is proved that every linear derivation of a nest algebraalgN is continuous provided that one of the following conditions is satisfied: (1) 0+ (?) 0. (2.X_ (?) X. (3) there exists a non-trivial idempotent p in algN such that the range of p belongsto N. It is also proved that every additive derivation of a nest algebra is automatically linearif the underlying normed space is infinite dimemnsional.

关键词： Nest algebra Derivation Continuity Linearity Banach space

Density functional theory for adsorption of HCHO on the FeO(100) surface

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Journal of Natural Gas chemistry 2010年第1期19卷 21-24页

作者： Lingling Wang, Wenkai Chen department of chemistry, Fuzhou {2., Fuzhou 350108, Fujian, china [a] department of chemistry Fuzhou University Fuzhou 350108 Fujian China

The density functional theory （DFT） and periodic slab model were used to get information concerning the adsorption of HCHO on the FeO（100） surface. A preferred η^2.（C,O）-di-σ four-membered ring adsorption conformation on the Fe-top site was found to be the most favorable structure with the predicted adsorption energy of 2.0.7 kJ/mol. The analysis of density of states, Mulliken population, and vibrational frequencies before and after adsorption showed clear weakening of the carbonyl bond, and high sp^3 character on the carbon atom.

关键词： density functional theory formaldehyde iron monoxide adsorption

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. College of chemistry & Environment Protection Engineering, Southwest university for Nationalities, Chengdu 610041,{2. 2. TH-UNIS Insight Co., Ltd., Beijing 100085,{2. 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology, Ministry of Education, department of chemistry, Tsinghua university, Beijing 100084,{2. 1. College of chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.