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The extremely cold 2009-2010 winter and its relationship with the Arctic oscillation

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Frontiers of physics 2013年第5期8卷 590-603页

作者： Xin-Yu Wen yong-Yun Hu ji-Ping Liu Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China 2Department of Atmospheric and Environmental Sciences University at Albany State University of New York NY 12222 USA

The Northern-Hemisphere high-latitude continents experienced extremely cold weathers in winter 2009 2010. In the present paper, we show that the cold winter was associated with the activity of tile Arctic oscillation （AO）, which demonstrated the strongest negative polarity over the past six decades and persisted from December, 2009 to March, 2010. It is found that variations of the surface AO was closely linked to stratospheric polar vortex anomalies, and that the surface AO phases followed downward propagation of stratospheric Northern-Hemisphere Annular mode （NAM） anomalies during the winter. The case of 2009-2010 winter provides us with a typical example that anomalous stratospheric signals can be used to improve skills of long-range weather forecast and intra-seasonal climate prediction in winter time. We also show that the E1 Nifio event, which started developing from May 2009, might contribute the formation of exceptionally negative and persistent AO and stratospheric NAM, particularly over North Pacific and North America.

关键词： Arctic oscillation Northern-Hemisphere Annular mode (NAM) stratosphere planetarywaves weather forecast

Optimal Generalized Case-Cohort Analysis with Cox's Proportional Hazards Model

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Acta Mathematicae Applicatae Sinica 2015年第3期31卷 841-854页

作者： yong-XIU CAO ji-CHANG YU YAN-YAN LIU School of Mathematics and Statistics Wuhan University School of Statistics and Mathematics Zhongnan University of Economics and Law

Generalized case-cohort design has been proved to be a cost-effective way to enhance the efficiency of large epidemiological cohort. In this article, we propose an inference procedure for estimating the unknown parameters in Cox＇s proportional hazards model in generalized case-cohort design and establish an optimal sample size allocation to achieve the maximum power at a given budget. The finite sample performance of the proposed method is evaluated through simulation studies. The proposed method is applied to a real data set from the National Wilm＇s Tumor Study Group.

关键词： Cox's proportional hazards model generalized case-cohort optimal allocation

Transcriptome datasets supply basic gene information for RNAi pest management and gene functional studies in Nephotettix cincticeps(Uhler)

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Journal of Integrative Agriculture 2016年第4期15卷 840-847页

作者： CHEN Tai-yu HOU ji-xiang LIN yong-jun National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University College of Plant Science & Technology Huazhong Agricultural University

RNA interference （RNAi） technology has the potential to be used in pest management in crop production. Here, the transcriptome of Nephotettix cincticeps （Uhler） was deeply sequenced to investigate the systematic RNAi mechanism and candidate genes for dsRNA feeding. In our datasets, a total of 81 225 transcripts were obtained with the length from 150 bp to about 4.2 kb. Almost all the genes related to the RNAi core pathway were proved to be present in N. cincticeps transcriptome. Two transcripts that respectively encode a systemic interference defective （SID） were identified in our da- tabase, indicating that the systematic RNAi pathway can function effectively in N. cincticeps. Our datasets not only supply basic gene information for the studies of gene expression and functions in N. cincticeps, such as the control genes for gene expression analysis, but also provide candidate genes for RNAi pest management, such as the genes that encode P450 monooxygenase, V-ATPase and chitin synthase.

关键词： Nephotettix cincticeps transcriptome RNA interference house-keeping genes

The Frattini Subalgebra of Restricted Lie Superalgebras

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1343-1356页

作者： Liang Yun CHEN Dao ji MENG yong Zheng ZHANG Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China Department of Mathematics Northeast Normal University Changchun 130024 P. R. China Department of Mathematics Nankai University Tianjin 300071 P. R. China

In the present paper, we study the Frattini subalgebra of a restricted Lie superalgebra （L, [p]）. We show first that if L = A1 ＋ A2 ＋… ＋An, then Фp（L） = Фp（A1）＋Фp（A2）＋…＋Фp（An）, where each Ai is a p-ideal of L. We then obtain two results： F（L） = Ф（L） = J（L） = L if and only if L is nilpotent; Fp（L） and F（L） are nilpotent ideals of L if L is solvable. In addition, necessary and sufficient conditions are found for Фp-free restricted Lie superalgebras. Finally, we discuss the relationships of E-p-restricted Lie superalgebras and E-restricted Lie superalgebras.

关键词： restricted Lie superalgebras E-p-restricted Lie superalgebras Frattini p-subalgebra Фp- free p-elementary

Formation and thermal stability of amorphous Ni-Mo-P alloys

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中国有色金属学会会刊：英文版 2004年第z1期14卷 147-151页

作者： ZHANG Yi MA Jun FANG yong-kui DUAN ji-guo School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China College of Chemistry and Chemical Engineering Daqing Petroleum Institute Daqing 163318 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of TechnologyHarbin 150090 China

The experimental researches on the chemical deposition of Ni-Mo-P amorphous alloys were carried out by adding Na2 MoO4 into acidic solutions. The optimum technology conditions were obtained by orthogonal design experiments. The structures and the relationship between compositions and their thermal stability were studied by energy spectrum (EC), scanning electron micrograph and X-ray diffraction spectrum. Compared with Ni-P amorphous alloys, the Ni-Mo-P amorphous alloys have high crystallization temperature and thermal stability, and the hardness reaches its peak when the annealing temperature is 500 ℃. With the increase of the heat treatment temperature, the surface morphology of the alloys changes.

关键词： chemical deposition Ni-Mo-P alloy amorphous phase crystallization

PROPAGATION OF LOVE WAVES IN PRESTRESSED PIEZOELECTRIC LAYERED STRUCTURES LOADED WITH VISCOUS LIQUID

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Acta Mechanica Solida Sinica 2008年第6期21卷 542-548页

作者： jianke Du Kai Xian ji Wang Yook-Kong yong Department of Mechanics and Engineering Science School of Engineering Ningbo University Ningbo 315211 China Department of Civil and Environmental Engineering Rutgers University Piscataway NJ 08854 USA

We investigate analytically the effect of initial stress in piezoelectric layered structures loaded with viscous liquid on the dispersive and attenuated characteristics of Love waves, which involves a thin piezoelectric layer bonded perfectly to an unbounded elastic substrate. The effects of initial stress in the piezoelectric layer and the viscous coefficient of the liquid on the phase velocity of Love waves are analyzed. Numerical results are presented and discussed. The analytical method and the results can be useful for the design of chemical and biosensing liquid sensors.

关键词： Love waves piezoelectric viscous liquid initial stress

Strain rate response of a Zr-based composite fabricated by Bridgman solidification

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 214-219页

作者： Jun-wei Qiao yong Zhang ji-heng Li Guo-liang Chen State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Zr58.5Ti14.3Nb5.2Cu6.1Ni4.9Be11.0 bulk metallic glass matrix composites,containingβ-Zr dendrites,were fabricated by Bridgman solidification at the withdrawal velocity of 1.0 mm/s through a temperature gradient of～45 K/*** to the increasing compressive strain rates,the monotonic increasing and decreasing were obtained for the maximum strength and the fracture strain,*** results show that high strain rate may induce the insufficient time for the interaction between shear bands and the crystalline phase,and early fracture occurs as a *** fractographs are consistent with the mechanical properties,and the failure mode of the present Zr-based composites is in agreement with the frame of the ellipse criterion.

关键词： bulk metallic glass composites Bridgman solidification mechanical properties

Equilibrium Crystallization Temperature of Syndiotactic Polystyrene γ Form

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Chinese Journal of Polymer Science 2018年第6期36卷 749-755页

作者： Hai Wang Chun-ji Wu Dong-Mei Cui yong-Feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The crystallization behavior of syndiotactic polystyrene（s PS） γ form undergoing annealing at various temperatures was investigated using the thermodynamic phase diagram based on Strobl＇s crystallization theory. On the basis of the differential scanning calorimetric results, it was observed that γ form melt-recrystallization occurred at a higher temperature with the increasing lamellar thickness, which resulted from the pre-annealing at the elevating temperature after acetone induced crystallization. Further temperature dependent small-angle X-ray scattering（SAXS） measurement revealed the evolution of the γ form lamellae upon heating until phase transition, involving three different regimes： lamellae stable region（25-90 °C）, melt-recrystallization region（90-185 °C） and pre-phase transition region（185-195 °C）. As a result, recrystallization line, equilibrium recrystallization line and melting line were developed for the s PS γ form crystallization process. Since the melt of γ form involved a γ-to-α/β form phase transition, the melting line was also denoted as the phase transition line in this special case. Therefore, the equilibrium crystallization temperature and melting（phase transition） temperatures were determined at around 390 and 220 °C on the basis of the thermodynamic phase diagram of the s PS γ form.

关键词： Syndiotactic polystyrene γ form Crystallization behavior Equilibrium crystallization temperature Equilibrium melting temperature

Editorial for special issue on advanced materials for energy storage and conversion

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International Journal of Minerals,Metallurgy and Materials 2021年第10期28卷 1545-1548页

作者： Qiao-bao Zhang yong-chang Liu Xiao-bo ji Department of Materials Science and Engineering College of MaterialsXiamen UniversityFujian 361005China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Powder Metallurgy College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China

The ever-increasing environmental problems and energy challenges have called urgent demand for utilizing green,efficient,and sustainable energy,thus promoting the development of new technologies associated with energy storage and conversion *** a wealth of energy storage devices,Li/Na/K/Zn/Mg ion batteries,metal-air batteries,and lithium-sulfur/all-solid-state batteries together with supercapacitors as advanced power sources have attracted considerable interest due to their conspicuous merits of high energy density,long cycle life,and good rate capability.

关键词： energy utilizing lithium