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Breeding Soybeans for Resistance to Physiological Race 4 of Cyst Nematode

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Agricultural Sciences in china 2002年第5期1卷 542-548页

作者： WANG Lian-zheng, WANG Lan, YAN Qing-shang, ZHAO Rong-juan, CHEN Pin-san and LI Qiang( Crop Breeding and Cultivation institute , Chinese Academy of Agricultural Sciences , beijing 100081 ,P.R. china Plant Protection institute , Chinese Academy of Agricultural Sciences , beijing 100094 ,P.R. china ) Crop Breeding and Cultivation institute Chinese Academy of Agricultural Sciences Beijing 100081 P. R. China plant Protection institute Chinese Academy of Agricultural Sciences Beijing 100094 P. R. China

Soybean cyst nematode causes serious damage to soybean production. In 1991, we started breeding studies on the resistance of soybeans to the cyst nematode. We found that near the beijing area the dominant race of the cyst nematode was race 4. We made more than 50 combinations of cross. The best combination was Dan 8 X PI 43.654 which resulted in marked segregation in plant height, pod habit, resistance to cyst nematode and maturity. We obtained many new soybean lines highly resistant to the cyst nematode through the pedigree method of selection, enlarging the number of plants of good combinations, alternative breeding in the North and in the South, and identification at an early generation. We now have released three soybean cultivars, Zhonghuang 12, Zhonghuang 13.and Zhonghuang 17 with moderate resistance to the cyst nematode in beijing, Anhui, Tianjin and Northern china. In addition, we obtained many lines which were highly resistant to the cyst nematode.

关键词： Soybean Resistance to the cyst nematode Breeding

Jurassic depositional records and sandstone provenances in Hefei Basin,central china:Implication for Dabie orogenesis

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Jurassic depositional records and sandstone provenances in H...

Symplectic and Multisymplectic Fourier Pseudospectral Discretizations for the Klein-Gordon Equation

中国科学院地质与地球物理研究所2004学术年会

作者： Zhong Li,~* Renwei Li,Shu Sun and Qingchen Wang institute of geology and Geophysics,Chinese Academy of Sciences,beijing {3.,china

Detrital composition and major element geochemistry of Jurassic sandstones in the south Hefei Basin,central china,show their provenance to be the Dabie Mountains, whose tectonic attributes are closely related to continent-island arc *** was found that a provenance change,from recycled orogen signatures and mixed orogenic sandstones to arc orogen,occurs from the lower Middle Jurassic to the Upper Jurassic (the Zhougongshan Formation).Dissected magmatic arc sources were gradually exposed in the Dabie Mountains due to intensive exhumation during the Late Jurassic,particularly after the Fenghuangtai depositional ***,it can be infered that the magmatic arc was initially present in both the Early Paleozoic and the Triassic,according to isotopic dating studies in previously published reports.δC-δO tracing between existing marbles of different strata in the Dabie block and marble gravels of the Fenghuangtai Formation in the Hefei Basin indicate that partial lithostratigraphic units for the Jurassic provenances have entirely disappeared from the Dabie block;therefore,it is impossible to reconstruct integral orogenic processes from studies on the remaining Dabie block alone. These findings,together with basin-fill sequences,also suggest that the Hefei Basin was mainly subjected to compressive mechanical regimes rather than extensional regimes in the Jurassic,which resulted in reverse-grading clastic depositional sequences,and is probably related to the northward intracontinental deep subduction of the Yangtze Plate. Regional exhumation properties and a tectonic model of the Late Mesozoic Dabie orogenesis are discussed in this paper.

关键词： basin-fill sequence Dabie Mountains Hefei Basin Mesozoic sandstone provenance

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Symplectic and Multisymplectic Fourier Pseudospectral Discre...

Effect of cultivating croplands and grazing in arid grassland habitats on the conservation of melitaeine butterflies in a mountainous area in Northern china

中国科学院地质与地球物理研究所2006学术年会

作者： JING-BO CHEN institute of geology and Geophysics,Chinese Academy of Sciences,P.0.Box 9825,beijing {3.,china

We present symplectic and multisymplectic formulations of the Klein-Gordon equation in this *** on these two formulations,we investigate the corresponding symplectic and multisymplectic Fourier pseudospectral *** relationship between these two kinds of Fourier pseudospectral discretizations is *** discretizations are also presented.

关键词： symplectic multisymplectic Klein-Gordon equation

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Science china(Life Sciences) 2007年第1期50卷 40-46页

作者： WANG YiFei1,2, CHEN JieJun1,3. LIU WenHua1,4 & XU RuMei1 1 Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, beijing Normal University, beijing 100875, china 2 Forestry Research {3., Chinese Academy of Forestry Sciences, beijing 100091, china 3.2} National Center for Biotechnology Development, Ministry of Science and Technology, beijing 100081, china 4 Center for Disease Control and Prevention of Guangdong Province, Guangzhou 5103.0, china 1. Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Beijing Normal University Beijing 100875 China 2. Forestry Research institute Chinese Academy of Forestry Sciences Beijing 100091 China 3. china National Center for Biotechnology Development Ministry of Science and Technology Beijing 100081 China 4. Center for Disease Control and Prevention of Guangdong Province Guangzhou 510300 China

In the study area (Yanjiaping Village, Hebei Province, china), grazing extensity varies at different loca-tions, small and discontinuous croplands are imbedded in some arid grassland, which are habitats for the melitaeine butterflies, Euphydryas aurinia and Melitaea phoebe. These two species of butterflies coexist in this area, in which grazing and cultivation are the main disturbances. Grazing and cultivation have a reciprocal effect on E. aurinia, rather than M. phoebe. We observed that E. aurinia preferred to occupy patches with moderate grazing and imbedded with small and discontinuous croplands, where E. aurinia also has high population density. The percentage of E. aurinia larval groups in the ribbings was significantly higher than that of M. phoebe, whereas larvae of both species tended to increase in recent years. Our data also showed that the population density and the patch occupancy rate of both E. aurinia and M. phoebe were the highest under moderate grazing. It indicates that cultivation of small and dis-continuous croplands within the patch has a significant effect on the population density of both spe-cies of melitaeine butterflies. Thus, to artificially create or maintain semi-natural habitats, comple-mented by moderate grazing, might be an ecological strategy to conserve melitaeine butterflies effec-tively. Considering the distinct impacts of cultivation and grazing on the population distribution and dynamics of the two different species, human disturbance in the mountainous area might be strategi-cally involved in proposing conservation plans for the target species in the future.

关键词： grazing croplands metapopulation conservation Euphydryas aurinia Melitaea phoebe

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中国地震断层与现代断裂运动

昆明工学院学报 1984年第4期 18-28页

作者：虢顺民国家地震局地质研究所

地震是一种地质现象。它的分布不是杂乱无章的,而是严格地依照断裂运动发生的。从这个观点说,地震直接与断裂运动有关。人类历史时期的地震活动,对整个地质时期来说,虽是短暂的一瞬间,但无论是历史地震还是现代地震,都属于地壳运动阶段... 详细信息

地震是一种地质现象。它的分布不是杂乱无章的,而是严格地依照断裂运动发生的。从这个观点说,地震直接与断裂运动有关。人类历史时期的地震活动,对整个地质时期来说,虽是短暂的一瞬间,但无论是历史地震还是现代地震,都属于地壳运动阶段中的最新活动。作者把产生这些地震的最新断裂运动称为现代断裂运动。

关键词：地震断层断裂运动断型地壳运动活动断裂带地震地震动中华人民共和国

低信噪比下的Turbo编译码算法研究及性能评估

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铁道学报 2004年第2期26卷 66-71页

作者：黄和斌肖扬北京莘夏科技开发有限责任公司北京100011 北京交通大学信息科学研究所北京100044

由于Turbo码优异的纠错性能,CDMA2000与WCDMA将其作为候选的信道编码方案。本文研究了Turbo码的基本原理和编解码算法,在此基础上对Turbo码编解码系统进行了计算机仿真。本文设计的Turbo码编解码采用了伪随机交织器,它将低重量输入信息... 详细信息

由于Turbo码优异的纠错性能,CDMA2000与WCDMA将其作为候选的信道编码方案。本文研究了Turbo码的基本原理和编解码算法,在此基础上对Turbo码编解码系统进行了计算机仿真。本文设计的Turbo码编解码采用了伪随机交织器,它将低重量输入信息序列产生低重量编码序列的关系打破,提高了Turbo码编解码系统性能。系统仿真结果及分析表明有译码迭代次数、RSC分量码,交织器大小与交织器图等几个因素会影响Turbo码编解码系统性能。

关键词：无线通信 Turbo码 LOG-MAP算法迭代译码

The bacterial diversity in surface sediment from the South china Sea

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Acta Oceanologica Sinica 2010年第4期29卷 98-105页

作者： WANG Guanghua DONG Junde LI Xiang SUN Huimin Key Laboratory of Marine Bio-resources Sustainable Utilization South China Sea Institute of Oceanology Chinese Academy of Science Guangzhou 510301 China Graduate University of Chinese Academy of Science Beijing 100049 China

16S rDNA sequencing results from this study and literatures demonstrate that sediment bacteria in the South china Sea （SCS） were very diverse,which contained 22 of the 24 phyla of bacteria investigated from marine sediment,however,it was very imbalance among *** bacterial diversity from 15 samples which covered a wide range of sediment types from 20 to 3.888 m in depth was studied in DGGE （denature gradient gel electrophoresis） in this *** DGGE results indicate that both sediment bacterial diversity and diversity difference among stations were *** representative and differential fingerprints among samples were recovered and sequenced,phylogenetic analysis indicates that they may belong to Proteobacteria （α-,β-,γ-,δ-,ε-）,Planctomycetes,Firmicutes,Chloroflexi,Acidobacteria,Actinobacteria,Nitrospirae,Gemmatimonadetes,candidate division WS3.and so on,of which,Gemmatimonadetes and candidate division WS3.bacteria were first detected in SCS *** study also shows that bacterial diversity analysis based on DGGE was more potential than traditional 16S rDNA clone library in multiple sample analysis.

关键词： bacterial diversity DGGE marine sediment South china Sea

A NUMERICAL MODEL OF OFFSHORE CURRENTS AND SOME TESTS

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Journal of Hydrodynamics 1989年第2期1卷 1-9页

作者： Zeng Qing-cun Ji Zhong-zhen Li Rong-feng LASG,institute of Atmospheric Physics,Academia Sinica,beijing,P.R.china

In this paper,a simple numerical model of offshore currents is presented. A calculation scheme based on the isometric,implicit difference method is used and the points at which various physical quantities are computed are distributed in a staggered *** finite difference scheme designed here conserve total generalized energy and it is solved by splitting into three systems,namely,the adjustment,development and dissipation *** results of the numerical verification indicate that this scheme is computational stable,and the simulated results are encouraging.

关键词： A NUMERICAL MODEL OF OFFSHORE CURRENTS AND SOME TESTS

DISCUSSION ON PREDICTION OF GREAT EARTHQUAKES BY MODERN STATISTICAL PHYSICS

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Chinese Science Bulletin 1989年第6期34卷 488-490页

作者：秦保燕 seismological institute of Lanzhou

The similarity phenomenon before the abrupt phase transition of different complexing system discussed in modern statistical physics gives an important enlightenment to the prediction of great earthquakes from nonlinea... 详细信息

关键词： nonlinearity process source system fluctuation aggravation self-similarity universal critical index.