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Pollen assemblages from different agricultural units and their spatial distribution in Anyang area

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Chinese Science Bulletin 2010年第6期55卷 544-554页

作者： WANG XueLi1,2.LI YueCong1,2.XU QingHai1,2.CAO XianYong1,2.ZHANG LiYan1,2.& TIAN Fang1,2.1 College of Resource and Environmental Sciences,Hebei Normal University,shijiazhuang 050016,china 2.Hebei Key Laboratory of Environmental Change and Ecological Construction,shijiazhuang 050016,china College of Resource and Environmental Sciences Hebei Normal University Shijiazhuang China Hebei Key Laboratory of Environmental Change and Ecological Construction Shijiazhuang China

Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human *** this paper,we reveal the characteristics of pollen assemblages in different agricultural units and their spatial distribution of major pollen taxa in the Anyang area where the human influences are serious,so as to get more information about climate change and human activities from pollen *** pollen assemblages of total 12. surface soil samples from different agricultural units (farm lands,vegetable plots,wastelands,cape-lands,woodlands,etc.) indicate that herbaceous pollen dominates the pollen assemblages with an average of 73%,mainly from Poaceae,Artemisia,Chenopodiaceae and Cruciferae;arboreal pollen percentages reach 18%,mainly from Pinus and Ulmus;shrub pollen and fern spores have very low *** general,pollen assemblages are consistent with vegetation composition,though some differences also exist in different agricultural *** farmlands and vegetable lands,Poaceae pollen has the highest percentages (averaging 2.%) compared to other agricultural units with dominant corn or wheat pollen,while in wastelands and woodlands,arboreal and Artemisia pollen percentages have higher values (averaging 2.% and 19% respectively).Cruciferae has the highest pollen percentages (70%) in *** pollen assemblages and PCoA can generally identify the vegetable plots,farmlands,woodlands,wastelands,and *** and Artemisia pollens mainly appear in the western part of Anyang,which is consistent with the parent plants;Poaceae pollen mainly exist in the eastern part with more farmlands;Chenopodiaceae pollen mainly appear in the urban areas and near major roads where human influences are stronger,Cruciferae pollen can mainly be found in the urban area and in the northwest part of Anyang where more vegetables are planted.

关键词：安阳地区空间分布花粉组合单位农业

Optimal controlled teleportation via several kinds of three-qubit states

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1529-1556页

作者： GAO Ting1,2. YAN FengLi2.3 & LI YouCheng3 1 College of Mathematics and Information Science, Hebei Normal University, {2., china 2.Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching, Germany 3 College of Physics and Information Engineering, Hebei Normal University, {2., china College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050016 China Max-Planck-Institut für Quantenoptik Hans-Kopfermann-Str. 1 D-85748 Garching Germany College of Physics and Information Engineering Hebei Normal University Shijiazhuang 050016 China

The probability of successful controlled teleportation of an unknown qubit using a general three-particle state is investigated. The analytic expressions of maximal probabilities via several kinds of tripartite states... 详细信息

关键词： controlled teleportation three-qubit state maximal probability

Brassinosteroid signal trans-duction: An emerging picture

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Chinese Science Bulletin 2003年第18期48卷 1906-1912页

作者： WANG Qiaomei1 & MA Ligeng2.1. Department of Horticultural Science, Zhejiang University, Hangzhou 31002., {2. 2. Department of Biology, Hebei Normal University, shijiazhuang 050016, {2. Correspondence should be addressed to Ma Ligeng (e-mail: ligeng.ma @yale.edu) Department of Horticultural Science Zhejiang University Department of Biology Hehei Normal University Shijiazhuang

Steroid hormones play essential roles in animal growth and development. Steroid signaling in animal system is focused on the direct gene regulation response mediated by its nuclear receptors. Recently, steroid hormones are also found in plants. Identification of BRI1 — a critical compo-nent of the plasma-membrane steroid receptor complex, and the related signal transduction pathway mediated by the membrane receptor have revealed an elementary picture of BR signaling from the cell surface perception to the activa-tion of BR-responsive nuclear genes.

关键词： plants Brassinosteroids signal transduction BRI1 cross talk.

Synthesis of iron(Ⅲ)-doped nanostructure TiO_2.SiO_2.and their photocatalytic activity

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Rare Metals 2007年第6期26卷 565-571页

作者： CHEN Rufen ZHANG Lei SONG Xiuqin WEI YU HOU Denglu College of Chemistry and Material Science Hebei Normal University Shijiazhuang Hebei 050016 China Key Laboralory of Advanced Film of Hebei Province Shijiazhuang Hebei 050016 China

Iron（Ⅲ）-doped nanostructure TiO2.coated SiO2.（TiO2.SiO2. particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2.colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy （FTIR）, SEM, EDS, XPS, and XRD. The experimental results show that TiO2.nanopowders on the surface of SiO2.particles are well distributed, the amount of TiO2.is increased with the adding of coating layers, the pure anatase-TiO2.coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3＋-doped TiO2.SiO2.is higher than that of undoped TiO2.SiO2.

关键词： TiO2.coating SiO2.particle nanostructure layer-by-layer assembly doping photocatalytic activity

λ-fold indecomposable large sets of Steiner triple systems

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Science china Mathematics 2010年第11期53卷 2877-2888页

作者： JI LiJun1, TIAN ZiHong2. & KANG QingDe2.1Department of Mathematics, Suzhou University, Suzhou 2.5006, china 2.ollege of Mathematics and Information Science, Hebei Normal University, shijiazhuang 050016, china 1. Department of Mathematics Suzhou University Suzhou 215006 China2. College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050016 China

A family (X, B1), (X, B2., . . . , (X, Bq) of q STS(v)s is a λ-fold large set of STS(v) and denoted by LSTSλ(v) if every 3-subset of X is contained in exactly λ STS(v)s of the collection. It is indecomposable and denoted by IDLSTSλ(v) if there exists no LSTSλ (v) contained in the collection for any λ 1 and orders v ≡ 1, 3 (mod 6) do there exist IDLSTSλ(v)? In this paper, we use partitionable candelabra systems (PCSs) and holey λ-fold large set of STS(v) (HLSTSλ(v)) as auxiliary designs to establish a recursive construction for IDLSTSλ(v) and show that there exists an IDLSTSλ(v) for λ = 2. 3, 4 and v ≡ 1, 3 (mod 6).

关键词： Steiner triple system large set candelabra system indecomposable

The existence spectrum for overlarge sets of pure directed triple systems

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Science china Mathematics 2010年第10期53卷 2801-2810页

作者： LIU YuanYuan1 & KANG QingDe2.1Department of Fundamental Science,North china Institute of Aerospace Engineering,Langfang 065000,china 2.nstitute of Mathematics,Hebei Normal University,{2.,china 1. Department of Fundamental Science North China Institute of Aerospace Engineering Langfang 065000 China2. Institute of Mathematics Hebei Normal University Shijiazhuang 050016 China

A directed triple system of order v,denoted by DTS(v),is a pair (X,B) where X is a v-set and B is a collection of transitive triples on X such that every ordered pair of X belongs to exactly one triple of B.A DTS(v) (X,A) is called pure and denoted by PDTS(v) if (a,b,c) ∈ A implies (c,b,a) ∈/ *** overlarge set of PDTS(v),denoted by OLPDTS(v),is a collection {(Y \{yi},Aij) : yi ∈ Y,j ∈ Z3},where Y is a (v+1)-set,each (Y \{yi},Aij) is a PDTS(v) and these Ais form a partition of all transitive triples on Y .In this paper,we shall discuss the existence problem of OLPDTS(v) and give the following conclusion: there exists an OLPDTS(v) if and only if v ≡ 0,1 (mod 3) and v > 3.

关键词： overlarge set pure directed triple system directed candelabra system

Lyapunov exponents for continuous random transformations

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Science china Mathematics 2010年第2期53卷 413-424页

作者： ZHU YuJun & ZHANG JinLian College of Mathematics and Information Science, Hebei Normal University, shijiazhuang 050016, china 1. College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050016 China

In this paper, the concept of Lyapunov exponent is generalized to random transformations that are not necessarily differentiable. For a class of random repellers and of random hyperbolic sets obtained via small pertur... 详细信息

关键词： random transformation Lyapunov exponent multiplicative ergodic theorem random repeller random hyperbolic set

Preparation of Ultrafine Li4+x AlxSi1-xO4 by Sol-Gel Method and Its Ionic Conductivity

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Rare Metals 2000年第3期19卷 231-236页

作者： Chen Rufen,Song Xiuqin and Liu Huating (陈汝芬) (宋秀芹) (刘华亭) Department of Chemistry,Hebei Normal University,shijiazhuang 050016,china Hebei Normal Univ Dept Chem Shijiazhuang 050016 Peoples R China

Solid electrolyte Li 4+ x Al x Si 1- x O 4 ( x =0～0.5) was prepared by sol gel *** powder samples were characterized by DTA TG,TEM,SEM and XRD. Ionic conductivity of the sintered sample was determined by means of A C impedance *** experimental results show that the solid solution range was 02. 3 added,the maximum conductivity of Li 4.4 Al 0.4 Si 0.6 O 4 was 8.612.10 -3 S·cm -1 at 300℃.The average grain size of samples was 70 *** sample prepared by sol gel method required lower temperature and presented higher ionic conductivity compared with the samples by the conventional solid state reaction.

关键词： Li 4+ x Al x Si 1- x O 4 Sol Gel method Ionic conductivity

Synthesis of Self-assembled Mesoporous Zirconia with Rheological Phase Reaction

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稀有金属材料与工程 2011年第S3期40卷 263-265页

作者： Wang Xiaoqiang1, Xia Wang1, Lu Baoqiang1, Zhen Congmian2.1Northeastern University at Qinhuangdao Branch, Qinhuangdao 066004, china 2.ebei Normal University, shijiazhuang 050016, china Northeastern Univ Dept Mat Sci & Engn Qinhuangdao Branch Qinhuangdao 066004 Peoples R China Hebei Normal Univ Shijiazhuang 050016 Peoples R China

The rheological phase reaction method was used to obtain the zirconia spherical particles with monodispersity and single-scale. And based on this, we got the colloidal dispersion of Zirconia (ZrO2.. Mesoporous zirconia were successfully synthesized by vacuum filtration or gravitational deposition as assembly methods using monodispersed PMMA as template. The precursor was studied by FT-IR, TG and DTA, these results further revealed that the precursor is ZrO(C6H5COO)2.2.2.. By the phase analysis in the XRD patterns it was proved that the ZrO2.crystallites have monoclinic phase structure. SEM results indicated that the aperture size is from 50-500 nm and increases with the process conditions changing, moreover, the sample has good thermal stability. This study shows the controllability of ZrO2.macroporous materials’ aperture size was realized at some extent.

关键词： ZrO2 mesoporous rheological phase reaction self-assemble