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Progress and prospects of studies on Polymyxa graminis and its transmitted cereal viruses in china

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Progress in Natural Science:Materials International 2005年第6期15卷 481-490页

作者： CHEN Jianping*(virology and Biotechnology Institute, zhejiang academy of agricultural sciences, Key Laboratory of Plant virology, Ministry of Agriculture and zhejiang Province, hangzhou 31002., china) virology and Biotechnology Institute Zhejiang Academy of Agricultural Sciences Key Laboratory of Plant Virology Ministry of Agri- culture and Zhejiang Province Hangzhou 310021 China

Polymyxa graminis is a eukaryotic obligate biotrophic parasite of plant roots that belongs to a poorly studied discrete taxonomic unit informally called “plasmodiophorids”. P. graminis is nonpathogenic, but has the ability to acquire and transmit nine plant viruses which belong to genera Bymovirus and Furovirus and cause serious diseases in cereal crop species and also result in significant yield reductions in china and elsewhere. Genus Bymovirus contains barley yellow mosaic virus (BaYMV), barley mild mosaic virus (BaMMV), wheat yellow mosaic virus (WYMV), wheat spindle streak mosaic virus (WSSMV), and oat mosaic virus (OMV), and genus Furovirus contains soil-borne wheat mosaic virus (SBWMV), oat golden stripe virus (OGSV), and newly identified Chinese wheat mosaic virus (CWMV) and soil-borne cereal mosaic virus (SBCMV). All these viruses have been sequenced and their worldwide distributions have been studied. The viruses are protected by the environment within P. graminis resting spores that may remain dormant but viable for decades (probably until a suitable host plant is encountered). Spontaneous deletion mutants of SBWMV, OGSV and OMV are detected, and these deletion mutants are not transmissible by the fungus. The persistent, soil-borne nature of these diseases makes the use of virus-resistant crop varieties currently the only practical and environmentally friendly means to control them, and a large number of disease resistant germplasms have been screened.

关键词： Polymyxa graminis cereal viruses genus Bymovirus genus Furovirus.

Line bundles on non-primary Hopf manifolds

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Science china Mathematics 2004年第4期47卷 538-551页

作者： LIU Weiming & ZHOU XiangyuInstitute of Mathematics, academy of Mathematics and System sciences, Chinese academy of sciences, Beijing 100080, china department of Mathematics, zhejiang University, hangzhou 31002., china 1. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. department of Mathematics Zhejiang University 310028 Hangzhou China

Let X be a Hopf manifolds with Abelian fundamental group, L any flat line bundle on X, we give a formula for computing explicitly the cohomology Hq(X, Ωp(L) using the method of group action and the generalized Douady... 详细信息

关键词： Hopf surface, cohomology, line bundle, sections.

Boundedness of a class of super singular integral operators and the associated commutators

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Science china Mathematics 2004年第6期47卷 842-853页

作者： CHEN Qionglei & ZHANG Zhifei department of Mathematics, zhejiang University, hangzhou 31002., china academy of Mathematics and System sciences, Chinese academy of sciences, Beijing 100080, china 1. department of Mathematics Zhejiang University 310028 Hangzhou China 2. academy of Mathematics and System sciences Chinese Academy of Sciences 100080 Beijing China

In this paper we give the (L p α, L p ) boundedness of the maximal operator of a class of super singular integrals defined by $$T_{\Omega ,\alpha }^* f(x) = \mathop {\sup }\limits_{\varepsilon > 0} \left| {\int_{|x - y| > \varepsilon } {b(|y|)} \Omega (y)|y|^{ - n - \alpha } f(x - y)dy} \right|,$$ which improves and extends the known result. Moreover, by applying an off-Diagonal T1 Theorem, we also obtain the (L p , L q ) boundedness of the commutator defined by $$C_{\Omega ,\alpha } f(x) = p.v. \int_{\mathbb{R}^n } {(A(x)} - A(y))\Omega (x - y)|x - y|^{ - n - \alpha } f(y)dy.$$

关键词： singular integral operator maximal operator commutator T1 Theorem

POLYMERIZATION OF p-DIETHYNYLBENZENE INITIATED BY Ni(C≡CC_6H_4C≡CH)_2(PPH_3)_2

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Chinese Journal of Polymer Science 2001年第3期19卷 303-309页

作者： Mu-jie Yang Xiao-wei Zhan department of Polymer Science and Engineering zhejiang University hangzhou 31002., china Present address: Institute of Chemistry, Chinese academy of sciences, Beijing 100080, china 浙江大学浙江杭州

Homogeneous polymerization of p-diethynylbenzene initiated by nickel acetylide Ni(C ≡ C C_6H_4 C ≡ CH)_2(PPh_3)_2has been investigated in terms of different solvents, addition agents, atmosphere gases, catalyst concentrations, monomerconcentrations and polymerization temperatures. The yield and catalytic efficiency approach 88% and 11. 1 kg polymer/molNi, respectively, under the optimum conditions: [cat] = 0.01 mol/L, [M] = 1.0 mol/L, NEt_3/cat (mol ratio) = 3～5, 1,4-dioxane/toluene (volume ratio) = 1 and T = 25℃ for 5 h. The polymerization rate equation can be expressed as R_p =k_p[M][cat]~2, where k_p= 0.47 L^2. mol^(-2)·S^(-1) (25℃). The overall polymerization activation energy was found to be203 kJ·mol^(-1). Poly(p-diethynylbenzene) so obtained is soluble in THF, CHCl_3 and toluene with weight-average molecularweights as high as 27, 100 and a rich-trans extended π-conjugated polyene chain structure with pendent groups ofp-C_6H_4C≡CH.

关键词： Polymerization p-Diethynylbenzene Nickel acetylide Catalyst

Local and global behavior for algorithms of solving equations

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Chinese Science Bulletin 2001年第6期46卷 441-448,529页

作者： WANG Xinghua & LI Chongdepartment of Mathematics, zhejiang University, hangzhou 31002., china academy of Mathematics and System sciences, Chinese academy of sciences, Beijing 100080, china department of Applied Mathematics, Southeast University, Nanjing 210096, china department of Mathematics Zhejiang University Hangzhou China academy of Mathematics and System sciences Chinese Academy of Sciences Beijing China department of Applied Mathematics Southeast University Nanjing China

The theory of 'point estimate' and the concept of 'general convergence', which were put forward by Smale in order to investigate the complexity of algorithms for solving equations, have been producing a deep impact on the research about the local behavior, the semi-local behavior and the global behavior of iteration methods. The criterion of point estimate introduced by him not only provides a tool for quantitative analysis of the local behavior but also motivates the establishing of the unified determination for the semi-local behavior. Studying the global behavior in the view of discrete dynamical system will lead to many profound research subjects and open up a rich and colorful prospect. In this review, we will make a summarization about the research progress and some applications in nonsmooth optimizations.

关键词： Banach space nonlinear operator equation point esti-mate Sullivan domain nonsmooth optimization.

Energy functionals and killing transform

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Chinese Science Bulletin 1997年第19期42卷 1593-1596页

作者： YING Jiangangdepartment of Mathematics, zhejiang University, hangzhou 31002., china Istitute of Applied Mathematics, Chinese academy of sciences, Beijing 100080, china department of Mathematics Zhejiang University Hangzhou China Istitute of Applied Mathematics Chinese Academy of Sciences Beijing China

LET X=（Xt,Px） be a right Markov process with state space （E,ε）, semigroup （P1） andresolvent （Uq）. As in ref.[1, 2], we denote by Excq（X ）, Disq（X） and Conq（X） thecones of excessive, dissipative, conservative measures of X, respectively, and by Sq（X） thecone of excessive functions of X. By convention we drop the superscript q when it is zero. LetMF be the set of all exact multiplicative functional of X. For any given M∈MF, writeEM:= {x∈E:PM0 = 1 = 1} and SM: = inf} t>0: M1= 0 } for the set of

关键词： right processes multiplicative functionals Revuz measures energy functional capacity.

Structural phase transition in nanostructured γ-Fe_2O_3

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Chinese Science Bulletin 1997年第11期42卷 894-897页

作者： YE Xisheng, SHA Jian, SONG Hongqin, JIAO Zhengkuan, LU Guanglie, PENG Zifei and ZHANG Lide1. department of Physics, zhejiang University, hangzhou 31002., china 2. Central Laboratory, hangzhou University, hangzhou 31002., china 3. Institute of Solid State Physics, Chinese academy of sciences, Hefei 230031, china department of Physics Zhejiang IJniversity Hangzhou China Central laboratory Hangzhou University Harigzhou China Institute of Solid State Physics Chinese Academy of Sciences Hefei China

DUE to their specific physical,chemical and mechanical properties and large application proba-bility in many fields,nanostructured materials have been developing very fast in the recent *** stability is an important property of the *** interesting resultshave been obtained in the study of the thermal stability of nanostructured materials.

关键词： nanostructured γ-Fe2O3 differential thermal analysis (DTA) XRD microstructlire structural phase transition.

Effect of Waterlogged and Aerobic Incubation on Enzyme Activities in Paddy Soil

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Pedosphere 2006年第4期16卷 532-539页

作者： WANG Xiao-Chang LU Qin department of Tea Science College of Agriculture and Biotechnology Zhejiang University Hangzhou 31002g （China） Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

An incubation experiment with soil water content treatments of 0.15 （W1）, 0.20 （W2）, and 0.40 （W3） g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, china, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease （P ≤ 0.05） of fluorescein diacetate （FDA） and /3-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited （P ≤ 0.05） arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation （W1 and W2 treatments） significantly increased （P ≤ 0.05） FDA, alkaline phosphatase, and /3-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereas /3-D-glucosidase activity decreased. A significant difference （P ≤ 0.05） was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,/3-D-glucosidase and urease were usually not significant （P ≤ 0.05）. No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.

关键词： aerobic incubation enzyme activity paddy soil waterlogging

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese Science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1, ZHAO Zhenhua 1, SHI Manquan 1, YANG Shufeng 2 and CHEN Hanlin 2 1. Guangzhou Institute of Geochemistry, Chinese academy of sciences, Guangzhou 510640, china 2. department of Earth sciences, zhejiang University, hangzhou 31002., china Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China department of Earth sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at 261 MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.