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Phylogeny of higher taxa of hexapoda according to 12sRNA sequences

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Chinese Science Bulletin 2001年第10期46卷 840-842页

作者： ZHANG Yazhou ZHANG Yaping LUAN Yunxia CHEN Yongjiu YIN Wenying Shanghai Institute of Entomology Chinese Academy of SciencesShanghai 200025China Laboratory of Cellular and Molecular Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China

The phylogenetic relationship of Hexapoda has been debated for a long time, which will be resolved mainly depending on the settlement of monophyly, affinities and interrelationships among Protura, Collembola and Diplura. Mitochondrial 12sRNA gene about 355 bp fragments from one proturan species, two collembolan species, two dipluran species and one oribatid species were sequenced. The Ki-mura 2-parameter distances were calculated and a series of molecular phylogenetic trees were reconstructed by using the N-J method, from which the following points were drawn: (i) Protura and Collembola compose a monophyletic group representing absent-cerci; (ii) Diplura is not a monophyletic group, in which Campodeoid with filiform cerci belongs to a clade and Japygoid with pincer cerci and Ectognatha compose another clade, that is, Insecta s. str. stemmed from Japygoid. So it would be suggested that the phylogenetic relationship of Hexapoda is [Parainsecta (Collembola + Protura) +Campodeoid +Insecta (Japygoid +

关键词： Hexapoda 12sRNA phytogeny higher taxa monophyly.

Non-oxidative dehydro-oligomerization of methane to higher molecular weight hydrocarbons at low temperatures

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Science China Chemistry 1997年第2期40卷 161-164页

作者：王林胜徐奕德陶龙骧 State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

The non-oxidative dehydro-oligomerization of methane to higher molecular weight hydrocarbons such as aroma tics and C2 hydrocarbons in a low temperature range of 773-973 K with Mo/HZSM-5,Mo-Zr/HZSM-5 and Mo-W/HZSM-5 catalysts is studied.The means for enhancing the activity and stability of the Mo-containing catalysts under the reaction conditions is reported.Quite a stable methane conversion rate of over 10% with a high selectivity to the higher hydrocarbons has been obtained at a temperature of 973 K.Pure methane conversions of about 5.2% and 2.0% have been obtained at 923 and 873 K,respectively.In addition,accompanied by the C2-C3 mixture,tht- methane reaction can be initiated even at a lower temperature and the conversion rate of methane is enhanced by the presence of tne initiator of C2-C3 hydrocarbons.Compared with methane oxidative coupling to ethylene,the novel way for methane transformation is significant and reasonable for its lower reaction temperatures and high selectivity to the desired

关键词： non-oxidative dehydro-oligomerization methane low reaction temperature Mo-containing ZSM-5 higher hydrocarbons benzene

Uniform Convergence of higher Order Quasi Hermite-Fejer Interpolation

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Chinese Science Bulletin 1994年第6期39卷 441-448页

作者：王子玉田继善 Department of Mathematics Henan University Kaifeng 475001 PRC

Let Xn={xkn=cosθkn: θkn=（kπ）/（n+1）, 1≤k≤n}be the node system which consists ofroots of Un （x） =（sin（n+1）θ）/（sinθ）（x=cosθ θ∈[0,π]）, the second kind Chebyshevpolynomical. All the symbols below have the same meaning as Ref. [1]if notspecifically defined. We shall consider a kind of new interpolating problem in thisnote. For any non-negative integer q and f∈C[-1, 1], it is well known that thepolynomial Qnq（f）∈ПN （N=2（q+1）（n+1） -1） satisfying the following conditions isuniquely determined:Qnq(f, xkn) =f(xkn), 1≤k≤n; Qnq（f,±1）=f（±1）,Qnqj(f,xkn)=cjkn, 1≤k≤n,1≤j≤2q+1,Qnqj（f,1）=djn, Qnqj（f,-1）=gjn, 1≤j≤q,where cjkn,djn, gjnare any given real numbers. Qnq（f）is called the higher orderquasi Hermite-Fejer interpolation of f.We

关键词： second kind Chebyshev nodes higher order quasi Hermite-Fejer interpolation uniform convergence approximation order.

EXCITATION ENERGY TRANSFER IN VITRO BETWEEN PHYCOBILIPROTEINS AND THYLAKOID PHOTOSYSTEM Ⅱ OF higher PLANTS

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Chinese Journal of Oceanology and Limnology 1992年第4期10卷 340-346页

作者：仵小南曾呈奎 E.M.B.L. Institute of Oceanology Academia Sinica Qingdao 266071

The excitation energy transfer from phycobiliproteins to thylakoid PSII of higher plants was investigated. When incubated with spinach thylakoids, phycobiliproteins isolated from red and blue- green algae transferred light energy absorbed to spinach PSII. The efficiency of energy transfer was dependent on the kind of phycobiliproteins used. If spinach thylakoids were replaced by the thylakoids of Brassica chinensis, R phycoerythin or C- phycocyanin did not transfer their excitation energy to PSII of Brassica chinensis unless allophycocyanin was present.

关键词： phycobiliproteins higher plants photosystem II energy transfer bioreactor

BOUND STATES OF THE CHARGED BOSONS IN higher DIMENSIONAL SPHERICALLY SYMMETRIC SPACE-TIMES

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Chinese Science Bulletin 1991年第18期36卷 1512-1515页

作者：蔡荣根 Department of Physics Qinghai Normal University Xining 810008 PRC

In recent years, many authors have widely researched into quantum gravitational bound states around black holes which have important relation to the studies on the quantum cosmology and its vacuum theory. Because of t... 详细信息

关键词： higher dimensional space-times Reissner-Nordstrm metric bound states of boson.

Domestic Cosmetic Products Take higher Position

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中国对外贸易：英文版 2023年第2期 34-35页

作者： Ada Wang 不详

The recent years have witnessed the exit of many foreign cosmetic brands from the Chinese market,such as Revlon and e.l.f.Since 2021,about 20 foreign cosmetic brands have withdrawn from the Chinese market,where they c... 详细信息

关键词： market witnessed higher

ON EXISTENCE OF higher ORDER IMMERSIONS

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Chinese Science Bulletin 1991年第1期36卷 12-16页

作者：李贵松 Institute of Systems Science Academia Sinica Beijing 100080 PRC

Ⅰ. INTRODUCTIONThroughout this note, all manifolds are assumed to be smooth and closed. We refer to [1]—[3] for the definitions and basic properties of higher order tangent bundles and pth order nonsingular immersio... 详细信息

关键词： higher order immersions existence codimension n-2.

Identification of the Wave-Particles Interaction in Space Plasma Using higher-Order Statistics

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 41-45页

作者： Zhao Zhengyu, Shi Xianqing, F. Lefeuvre, A. Masson(College of Electronic Information, Wuhan University, Wuhan 430072, China)(LPCE/CNRS, 45100 Orleans Cedex 02, France)

The interaction of wave-particles and wave-wave in the space plasmas are essentially non-linear or non-Gaussian processes. Using the higher-order statistical analyses methods (higher-order moments and bi-tri correlation or bi-tri spectrum), its physical properties can be described. The question addressed in this paper is that of the usefulness of higher-order statistical analysis for identification of the wave-particles interaction in space plasmas. The signals handled are from the ARCAD-3 ISOPROBE experiment on ELF frequency range, then strong electrostatic turbulence and electron density irregularities. Second and third order statistical analyses are applied: first, on time series associated with each type of measurement, then, on the two types. All results are presented for one typical case. Correlation functions estimated over the corresponding time intervals point out the existence of a, non-linear interaction between these fluctuations and electrostatic filed.

关键词： Key words wave particles interaction space plasmas higher order statistics

A DISCUSSION ON THE CREDIT-HOUR SYSTEM IN higher ENGINEERING EDUCATION

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北京大学学报（哲学社会科学版） 2007年第S2期44卷 39-41页

作者： Jing Rui Qiao Weiyang(School of Automatization Northwestern Polytechnical University,Xi’an 710072)

This thesis looks back the practice of university credit-hour system and analyzes the drawback of school year system;furthermore it puts forward the real significance of credit-hour system reform and tells us its new vigorousness and motivation to the higher learning administration.At the same time this thesis discusses the process of building up high-quality credit hour system and indicates how to establish and perfect higher learning credit-hour system.

关键词： credit-hour system school year system university year credit hour system higher engineering education higher learning