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中国科学：技术科学英文版 2010年第4期53卷 969-975页

作者： HU YanMing1,2.& NIE ChaoQun1 1 key laboratory of Advanced Energy and Power Technology,{2. of Engineeting Thermophysics,chinese {3. of Science,beijing 100190,China 2.graduate school of chinese academy of sciences,beijing 100190,China 1. key laboratory of Advanced Energy and Power Technology Institute of Engineeting Thermophysics Chinese Academy of Science Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100190 China

Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

关键词： axial compressor IGV surge DSP techniques off-design

A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

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Progress in Natural Science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (State key laboratory of Information Security, {2. {3. of chinese academy of sciences, beijing 10004., China) [a]State key laboratory of Information Security Graduate School of Chinese Academy of Sciences Beijing China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2., where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.

Threshold quantum secure direct communication without entanglement

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Science China(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3.& WEN QiaoYan2.1 College of Computer Science and Technology, beijing University of Technology, beijing 10002., China 2.{2. of Science, beijing University of Posts and Telecommunications, beijing 100876, China 3.State key laboratory of Information Security (graduate {2. of chinese academy of sciences),{13., China 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. State key laboratory of Information Security ({2. {3. of chinese academy of sciences) Beijing 100049 China 2. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Identification of high-lipid producers for biodiesel production from forty-three green algal isolates in China

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Progress in Natural Science:Materials International 2011年第4期21卷 269-276页

作者： An-yue LIU~(1,2.,Wei CHEN~1,Ling-ling ZHENG~1,Li-rong SONG~1 1.State key laboratory of Freshwater Ecology and Biotechnology,{2. of Hydrobiology, chinese academy of sciences,wuhan 43.072.China 2.graduate school,chinese academy of sciences,{13. 10004.,China [a] State key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China [b] graduate school Chinese Academy of Sciences Beijing 100049 China

To identify some desirable algal strains for our future research and/or the production of algae-based biofuel,43.green algal strains were successfully isolated from chinese freshwaters,and then incubated in the laboratory bioreactors for the growth and oil accumulation *** a 15 d incubation experiment,the accumulations of their biomass and total lipids,together with the lipid productivities for these green algal strains were systematically investigated and *** indicated that the accumulations of biomass for the 43.algal strains ranged from 0.53.g/L to 6.07 g/L during the experiments,with the highest biomass of 6.07 g/L for green algae Scenedesmus *** lipid content for the tested algal strains varied from 2.%to 51%of the dry biomass at the end of cultivation *** algae Chlorella pyrenoidosa was one of the best oil producers based on our investigations,with the total lipid content of 51%of dry *** the growth rates and the accumulations of intracellular lipids into the consideration,10 strains were considered to have significant potential for biofuel *** addition,the lipid productivities of the selected strains were further investigated.

关键词： biofuel microalgae lipid accumulation

Oxygen Permeation Behaviors and Hardening Effect of Titanium Alloys at High Temperature

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Journal of Materials Science & Technology 2004年第6期20卷 719-723页

作者： Hongyan MA, Maocai WANG and Weitao WUState key laboratory for Corrosion and Protection, {2. of Metai Research,{3., Shenyang 110016, Chinagraduate school of the{3., beijing 10003., China Lab. for Corrosion and Protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2. TB5 and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5) is much higher than α-Ti alloy (TA2. under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2. as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5) are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.

关键词： Microstructure Oxygen permeation Titanium Solid solution

Early scale effect and hemisphere superiority on the visual spatial attention:From the electrophysiological evidence of ERP

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Progress in Natural Science:Materials International 2004年第10期14卷 35-39页

作者： SONG Weiqun 1,3. ,GAO Yuan 1 and LUO Yuejia 1,2. (1.key laboratory of Mental Health,{2. of Psychology,chinese {3. of sciences,beijing100101,China 2.school of Psy-chology,Southwest China Normal University,Chongqing400715,China 3.graduate school of the chinese academy of sciences,Bei-jing10003.,China) chinese Acad Sci Inst Psychol Key Lab Mental Hlth Beijing 100101 Peoples R China SW China Normal Univ Sch Psychol Chongqing 400715 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

The visual attention mechanism in the brain was studied among16young subjects through the precue-target visual search paradigm using the event-related potentials(ERPs)technique,with the attentive ranges cued with different scales of chinese *** results showed that the response time was shortened as the cue scale was reduced,while the amplitudes of the P1and N1components of the ERPs *** results not only provided the electrophysiological evidence supporting the spotlight theory,but also indicated that the spotlight effect occurred during the early period of the selected *** kinds of separation in the P2.ffect were *** separation was between the P1effect and P2.ffect,which meant that additional computation was needed when the spatial scale of attention was enlarged;the other was between the left and right hemisphere of the P2.ffect,which indicates that the at-tentive processing of the cue range mainly occurred in the left hemisphere.

关键词： visual spatial attention cue scale spotlight effect hemisphere superiority event-related potential(ERP)

Novel gaseous transient species:generation and characterization

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Science China Chemistry 2007年第2期50卷 145-169页

作者： ZENG XiaoQing1,2.& WANG DianXun11 State key laboratory for Structural Chemistry of Unstable and Stable Species,{2. of Chemistry,chinese {3. of Sci-ences,beijing 100080,China 2.graduate school of chinese academy of sciences,beijing 10003.,China 1. State key laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. graduate school of{2. Beijing 100039 China

Due to special properties of transient species, such as short-lived, unstable, reactive, and even explosive, the generation and subsequent characterization is a great challenge for experimental chemists. In our laboratory, systematic researches have been carried out to investigate novel transient species: reactive halogen species (RHS), short-lived free radicals, and metastable pseudohalogen compounds, based on the successive technical improvements on the Hel Photoelectron spectroscopy (PES). In this review, the topic mainly focuses on innovative methods of generating novel transient species, and subsequent geometric and electronic structure characterizations of these species combined with quantum chemical calculations.

关键词： reactive halogen species radicals pseudohalogen compounds Hel Photoelectron Spectroscopy (PES) quantum chemical calculations

Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,China

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Science China(Technological sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1,2.CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3.ZHANG Hao 1,HE QiSheng 1,2.GAO MengXu 1,2.ZHAO Jian 1,2.ZHENG Sheng 1,2.CHEN Wei 1,2.& ZHENG LanFen 1 1State key laboratory of Remote Sensing Science,Jointly Sponsored by the {2. of Remote Sensing Applications of chinese academy of sciences and {3. Normal University,beijing 100101,China 2.{13. school of the chinese academy of sciences,beijing 10004.,China 3.Research {2. of Forest Resources and Information Techniques,{12. academy of Forestry,beijing 10009,China 1. State key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. graduate school of the{2. Beijing 100049 China 3. Research institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing 10009 China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 2.0 t,which has greatly contributed to the carbon fixation in northern China.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1A/B remote sensing

IMPLICITIZATION USING UNIVARIATE RESULTANTS

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Journal of Systems Science & Complexity 2010年第4期23卷 804-814页

作者： Liyong SHEN Chunming YUAN school of Mathematical sciences Graduate University Chinese Academy of Sciences Beijing 100049 China key laboratory of Mathematics Mechanization Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Among several implicitization methods, the method based on resultant computation is a simple and direct one, but it often brings extraneous factors which are difficult to remove. This paper studies a class of rational space curves and rational surfaces by implicitization with univaxiate resultant computations. This method is more efficient than the other algorithms in finding implicit equations for this class of rational curves and surfaces.

关键词： Implicitization rational space curves rational surfaces resultants.

Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science China Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3. MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. Chengdu institute of Organic Chemistry,{3., Chengdu 610041, China 2. Sichuan Fire Research institute of Public Security Ministry, Chengdu 61183., China 3. {3. school of the{3., beijing 10003., China Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research institute of Public Security Ministry 611830 Chengdu China 3. graduate school of the{2. 100039 Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 43..13., whose corresponding heat absorption capacities are 412.2. J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2. J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.