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Petrology and tectonic significance of the early Mesozoic granulite xenoliths from the eastern Inner Mongolia, china

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science china {2. sciences 2011年第10期54卷 1484-1491页

作者： SHAO JiAn 1,2.& WEI ChunJing 1 1 The Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education School of earth and space {2., Peking university, Beijing 100871, china 2.Key Laboratory of Mineral Resources, Chinese Academy of {2., Beijing 10002., china 1. The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of earth and space {2. Peking University Beijing 100871 China2. Key Laboratory of Mineral Resources Chinese Academy of Sciences Beijing 100029 China

Granulite xenoliths are found in the early Mesozoic diorite intrusions from Chifeng and Ningcheng areas, eastern Inner Mongolia. The granulites are granoblastic and weakly gneissic with mineral assemblage of hypersthene, diopside, plagioclase and minor biotite, amphibole and ilmenite. Some samples contain the intergrowth composed of labradorite and vermicular hypersthene, and some coarse-grained plagioclases of andesine and labradorite composition occasionally develop bytownite rims with vermicular hypersthene, indicating a possible presence of garnet. Presence of blastogabbroic texture and hypersthene with diopside exsolution lamellae in some samples suggests that the protolith of the granulite is norite or gabbro. On the basis of metamorphic research and thermobaric calculation, the evolution of the granulite xenoliths is summarized into the following stages: (1) Isobaric cooling of underplated noritic or gabbroic magma in the lower crust led to the formation of probable garnet-bearing medium-high pressure granulite. (2. These higher pressure granulites were adiabatically uplifted to upper crust by dioritic magma and transformed to low pressure two-pyroxene granulite during an isothermal decompression. (3) The two-pyroxene granulite underwent retrograde metamorphism of different degrees during an isobaric cooling process as a result of crystallization and cooling of the dioritic magma. The pyroxenite-dominated cumulates and the medium-high pressure granulites may have rejuvenated the lower crust during the early Mesozoic.

关键词： early Mesozoic granulite xenolith lower crust North china Craton

New ancient DNA sequences suggest high genetic diversity for the woolly mammoth (Mammuthus primigenius)

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Progress in Natural science:Materials International 2006年第4期16卷 379-386页

作者： YANG Shujuan, LAI Xulong, SHI Suhua, CHENG Shenghong, ZHOU Xiugao, YANG Xiujuan and YANG Hong department of earth {2., china university of Geosciences, Wuhan 430074, china department of Life {2., Sun Yat-Sen university, Guangzhou 5102.5, china Institute of Zoology, Chinese Academy of sciences, Beijing 100080, china Heilongjiang Provincial Museum, Harbin 150001, china department of sciences and technology, College of Arts and sciences, Bryant university, Smithfield, Rhode Island 02.17, USA and department of Geology and Geophysics, Yale university, New Haven, CT 0652., USA [a]department of earth {2. China University of Geosciences Wuhan China [b]Institute of Zoology Chinese Academy of Sciences Beijing China [c]department of Life Sceince Sun Yat-Sen University Guangzhou China [d]Heilongjiang Provincial Museum Harbin China [e]department of sciences and {2. College of Arts and Sciences Bryant University Smithfield Rhode Island USA [f]department of Geology and Geophysics Yale University New Haven CT USA

Partial DNA sequences of cytochrome b gene (mtDNA) were successfully retrieved from Late Pleistocene fossil bone of Mammuthus primigenius collected from the Xiguitu County ( Yakeshi), Inner Mongolia Autonomous Region and from Zhaodong, Harbin of Heilongjiang Province in northern china. Two ancient DNA fragments (109 bp and 12. bp) were authenticated by reproducible experiments in two different laboratories and by phylogenetic analysis with other Elephantidae taxa. Phylogenetic analysis using these sequences and published data in either separate or combined datasets indicate unstable relationship among the woolly mammoth and the two living elephants, Elephas and Loxodonta . In addition to the short sequences used to attempt the long independent evolution of Elephantidae terminal taxa, we suggest that a high intra-specific diversity existed in Mammuthus primigenius crossing both spatial and temporal ranges, resulting in a complex and divergent genetic background for DNA sequences so far recovered. The high genetic diversity in the extinct woolly mammoth can explain the apparent instability of Elephantidae taxa on the molecular phylogenetic trees and can reconcile the apparent paradox regarding the unresolved Elephantidae trichotomy.

关键词： Mammuthus primigenius genetic diversity ancient DNA phylogenetic analysis.

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. Institute of Laser Physics and Chemistry, Sichuan university, Chengdu 610064, china 2. {2. of Physics, Luoyang Normal College, Luoyang 47102., china 3. State Key Laboratory of Laser technology, Huazhong university of science and technology, Wuhan 430074, china Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 1. Institute of Laser Physics and Chemistry Sichuan University 610064 Chengdu China 2. State Key Laboratory of Laser technology Huazhong University of Science and Technology 430074 Wuhan China 3. department of Physics Luoyang Normal College 471022 Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Composition Operators on the Bloch space of Several Complex Variables

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Acta Mathematica Sinica,English Series 2000年第1期16卷 85-98页

作者： Jihuai Shi Luo Luo department of Mathematics,university of {2. and technology of china,Heifei 2.0036,P.R.china Fax:(0551)3631760 department of Mathematics University of Science and Technology of China Heifei 230036 P.R. China

In this paper,we study the boundedness and compactness of composition operator C on the Bloch space β（Ω）,Ω being a bounded homogeneous *** Ω=Bn,we give the necessary and sufficient conditions for a composition o... 详细信息

关键词： Bloch space Composition operator Bergman metric

A DISCRETE CHARACTERIZATION OF HERZ-TYPE TRIEBEL-LIZORKIN spaceS AND ITS APPLICATIONS

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Acta Mathematica Scientia 2004年第3期24卷 412-420页

作者： XuJingshi departmentofMathematics HunanUniversityChanysha410082China

In this paper, the author establishes a discrete characterization of the Herz-type Triebel-Lizorkin spaces which is used to prove the boundedness of pseudo-differential operators on these function spaces.

关键词： Herz-type space Triebel-Lizorkin space discrete characterization pseudo-differential operator maximal operator

Fractional Fourier domain equalization for single carrier broadband wireless systems

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science china(Information {2.) 2012年第10期55卷 2257-2268页

作者： HUANG KeWu 1,2.TAO Ran 1 & WANG Yue 1 1 department of Electronic Engineering,Beijing Institute of technology,Beijing 100081,{2. 2.Institute of Manned space System Engineering,{2. Academy of space technology,Beijing 100094,{2. 1. department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China2. Institute of Manned Space System Engineering China Academy of Space Technology Beijing 100094 China

In this paper,a novel single carrier equalization approach in the fractional Fourier domain(FRFD) is *** can remove all the inter-symbol interference(ISI) and avoid the considerable noise enhancement of the frequency domain-zero forcing(FD-ZF) *** the fractional Fourier transform makes a chirp spread,the impulse response of the deep fading channel may be flattened in some orders of the FRFD while it would be greatly attenuated in the *** searching for an optimal order under certain criterion,we take advantages of the ZF algorithm to mitigate the effects of the ISI *** approach can overcome the contradiction between the ISI mitigation and the noise enhancement of the FD-ZF *** analysis and simulation results show that the proposed FRFD-ZF equalizer can achieve a significant performance and have the same computation cost O(N log N) as the conventional FD linear equalizer,especially in the frequencyselective deep-fading channels.

关键词： fractional Fourier transform single carrier systems zero-forcing equalizer frequency domain linear equalizer

On linking climate to Chinese dynastic change: Spatial and temporal variations of monsoonal rain

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Chinese science Bulletin 2010年第1期55卷 77-83页

作者： ZHANG DeEr1, LI Hong-Chun2.3, KU Teh-Lung2.4 & LU LongHua5 1 National Climate Center, Beijing 100081, china 2.department of {2. sciences & Research Center of Ocean Environment and technology, Cheng-Kung university, Tainan 70101, Taiwan, china 3 School of Geographical sciences, Southwest university of china, Chongqing 400715, china 4 department of {2. sciences, university of Southern California, Los Angeles, CA 90089, USA 5 Chinese Academy of Meteorological sciences, Beijing 100081, china National Climate Center Beijing China department of earth {2. & Research Center of Ocean Environment and technology Cheng-Kung University Tainan Taiwan China School of Geographical sciences Southwest University of China Chongqing China department of earth {2. University of Southern California Los Angeles USA Chinese Academy of Meteorological sciences Beijing China

The causal correlation or linkage between the East Asian Monsoon (EAM) intensity and rise/fall of Chinese dynasties recently proposed by high-resolution paleoclimate reconstructions is examined in detail. Aside from many exceptions to the correlation, both instrumental and historical climate records show strong spatial variations of rainfall on annual-to-decadal scales over eastern china. The relationship between rainfall and EAM intensity also exhibits regional disparity. These observations suggest: (1) Tak-ing paleo-proxy records from a single locality in eastern china to imply changes in drought/wetness as to affect the cultural and political history of china is fraught with uncertainty. (2. On annual-to-decadal scales, the thesis that δ18O in speleothems can be used as a proxy for the EAM strength lacks empirical underpinnings.

关键词：古气候重建东亚季风强降雨时空变化中国东部地区连接 EAM 高分辨率

Optimal MAC based cooperative spectrum sensing in cognitive radio networks

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science china(Information {2.) 2012年第6期55卷 1388-1396页

作者： CHEN Zhong 1,ZHANG XianDa 1 & YANG LanJuan 2.1 State Key Laboratory of Intelligent technology and Systems,Tsinghua National Laboratory for Information science and technology,department of Automation,Tsinghua university,Beijing 100084,china 2.Institute of Command Automation,PLA university of science and technology,Nanjing 2.0007,china 1. State Key Laboratory of Intelligent technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Automation Tsinghua University Beijing 100084 China2. Institute of Command Automation PLA University of Science and Technology Nanjing 210007 China

This paper considers a cognitive radio (CR) system in non-ideal fading wireless channels and pro-poses cooperative spectrum sensing schemes based on coherent multiple access channels (MAC),serving as an alternative way to improve the cooperative spectrum sensing performance and provide space diversity for spec-trum *** statistics are transmitted using a common channel from the secondary users (SUs) to a fusion center (FC) where the global decision is *** optimal scaling factors of the proposed schemes are obtained by maximizing the detection probability under a target false alarm probability and a transmit power *** the proposed optimal MAC scheme has high computational complexity,a sub-optimal solu-tion based on maximization of the deflection coefficient (DC) is also *** results show that the proposed algorithms can significantly improve the spectrum sensing performance and approach the detection baseline.

关键词： cognitive radio (CR) spectrum sensing multiple access channel (MAC) deflection coefficient optimization

Electric Field Effects on Animals:Mechanism of Seismic Anomalous Animal Behaviors (SAABs)

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earthquake Research in china 1997年第1期11卷 107-116页

作者： Huang Qinghua,Ikeya Motoji,and Huang Peihuadepartment of earth and {2. sciences,Graduate School of science,Osaka university,Osaka 560,Japan department of earth and {2. sciences,university of science and {12. of china,hefei 2.002.,china

Electric field effect on animals has been studied to investigate its relation with seismic anomalous animal behaviors(SAABs)in *** eel,crucian carp,catfish,and soft-shelled turtle responded to the threshold electric field of 1-10 V/m,while duck,goose,cat,sheep,pig,dog,and chicken all responded to the ground electric field of about tens of V/m,depending on the species as well as on *** of the behaviors caused by electric field were similar to those reported as SAABs such as alignment,sudden movement,panic,and *** intensity of electric field due to a major earthquake would have been over these threshold *** estimation based on an electromagnetic model of a fault has been made to induce SAABs as electric shocks to pulsed electric fields in *** seismic electric signals(SES)intensity might be estimated from the observation of SAABs.

关键词： : Seismic anomalous behaviors of animals (SAABs) Seismic electric signals (SES) Electromagnetism Piezoelectric effect Free charge