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Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

Science china Earth Sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1.2, DENG Chenglong1. ZHU Rixiang1.& XIE Fei3 1. Paleomagnetism and Geochronology Laboratory (SKL-LE), institute of Geology and Geophysics, Chinese {1. of Sci- ences, Beijing 1.0029, china 2. School of the Earth Sciences and Resources, china University of Geosciences, Beijing 1.0083, china 3. Hebei Province institute of Cultural Relics, Shijiazhuang 050000, china Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China School of the Earth Sciences and Resources China University of Geosciences Beijing China Hebei Province institute of Cultural Relics Shijiazhuang China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1.Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3 and 1.1.Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

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Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural Science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1.* and CHEN Wende2(1. School of Mathematical Sciences, Peking University, Beijing 1.0871. china 2. Laboratory of Systems and Control and Key State Laboratory of Information Security, {1. of Systems Science, academy of Mathematics and Systems Science, Chinese academy of Sciences, Beijing 1.0080, china) School of Mathematical Sciences Peking University Beijing 100871 China Laboratory of Systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

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On the knee of Galactic cosmic rays in light of sub-TeV spectral hardenings

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Chinese Physics C 2018年第7期42卷 113-122页

作者： Yi-Qing Guo1.2 Qiang Yuan1.3 1. Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory Chinese academy of Sciences Nanjing 21.008 {1. 2. Key Laboratory of Particle Astrophysics institute of High Energy Physics Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China

More than fifty years after the discovery of the knee in the cosmic ray （CR） spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recently, direct measurements from several space experiments found significant spectral hardenings of CR nuclei at ~200 GV. A joint modeling of the direct and indirect measurements may help to understand the experimental systematics and the physics of the knee. In this work, we update the phenomenological ＂poly-gonato＂ model to include the spectral hardenings, with a changing spectral index of γ ＋ β·logE. This modification gives a reasonable description of the CR spectra in a wide energy range. However, the fits to different data sets give different results. We find that the fit to the AMS-02 and CREAM data slightly favors a relatively low energy knee of the light components. In such a case, the expected all-particle spectra under-shoot the data, which may require an extra component of CRs. The fits to AMS-02 data and the light component （H＋He） data from the Tibet ASγ/ARGO-YBJ/WFCTA and KASCADE experiments give consistent results with the all-particle spectra. We further propose a possible physical realization of such a ＂modified poly-gonato＂ model of spectral hardenings by means of spatially-dependent diffusion of CRs. We find reasonably good agreement between the model predictions and the data for CR spectra, the secondary-to-primary ratios, and the amplitude of anisotropies.

关键词： cosmic ray knee spectrum propagation

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Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1.2 , GUO Qionglin~1.*, HU Wei~1. WANG Yaping~1.and ZHU Zuoyan~1.1. State Key Laboratory of Freshwater Ecology and Biotechnology, institute of Hydrobiology, Chinese {1. of Sciences, Wuhan 430072, china 2. Graduate School of Chinese {1. of Sciences, Beijing 1.0039, china) State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate School of Chinese academy of Sciences Beijing 100039 China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2-year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1.06 nucleotides is translated into a putative peptide of 602 amino acids, including an extracellular ligand-binding domain of 244 amino acids (aa), a single transmembrane domain of 24 aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2-year common carp, a 224 bp product was identified in liver and a 321.bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 321.bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2-year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2-year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

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Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2 & HUA Feng1.2,3 1. institute of Oceanology, Chinese {1. of Sciences, Qingdao 266071. china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 266061. china 3. Graduate School of the Chinese {1. of Sciences, Beijing 1.0039, china Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the Chinese academy of Sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

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Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1.3 , LI Congxian\+1.and CONG Youzi\+2 1. Marine Geology Laboratory, Tongji University, Shanghai 200092, china 2. First {1. of Oceanography, State Oceanic Administration of china, Qingdao 266003, china 3. Guangzhou {1. of Marine Geology Laboratory Tongji University Shanghai China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China First institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

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Some properties on multivariate filter banks with a matrix factorization

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Progress in Natural Science:Materials International 2005年第2期15卷 20-30页

作者： LIAN Qiaofang1. XIAO Hongying2* and CHEN Qiuhui3(1. Department of Mathematics, Beijing Jiaotong University, Beijing 1.0044, china 2. {1. of Mathematics, academy of Mathematics and System Sciences, Chinese academy of Sciences, Beijing 1.0080, china 3. Department of Scientific Computing and Computer Applications, Zhongshan University, Guangzhou 51.275, china) Dept. of Mathematics Beijing Jiaotong Univ. Beijing 100044 China Inst. of Mathematics Acad. of Math. and System Sci. Chinese Acad. of Sciences Beijing 100080 China Dept. of Scientific Computing Zhongshan Univ. Guangzhou 510275 China

A class of multivariate filter banks with a matrix factorization has been developed by Chen et al. The main purpose of this paper is to discuss some further properties of this kind of filter bank, such as the completeness, accuracy of the corresponding scaling functions and the relationships with Daubechies' wavelets and the multi-wavelets provided by Chui and Lian. Moreover, some examples are given to show that this kind of filter bank has a higher accuracy for the scaling functions.

关键词： filter banks completeness accuracy matrix factorization

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Similar component analysis

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Progress in Natural Science:Materials International 2006年第12期16卷 1343-1347页

作者： ZHANG Hong~1.*, WANG Xin~1. LI Junwei~2 and CAO Xianguang~1.1. Image Center, Astronautics School, BeiHang University, Beijing 1.0083, china 2. The 207th {1. of the Second academy of china Aerospace Science Industry Corporation, Beijing 1.0854, china) Image Center Astronautics School BeiHang University Beijing 100083 China The 207th institute of the Second {1. of china Aerospace Science Industry Corporation Beijing 100854 China

A new unsupervised feature extraction method called similar component analysis (SCA) is proposed in this paper. SCA method has a self-aggregation property that the data objects will move towards each other to form clusters through SCA theoretically, which can reveal the inherent pattern of similarity hidden in the dataset. The inputs of SCA are just the pairwise similarities of the dataset, which makes it easier for time series analysis due to the variable length of the time series. Our experimental results on many problems have verified the effectiveness of SCA on some engineering application.

关键词： clustering feature extraction similar component.

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Distribution and characteristics of gravelly soil liquefaction in the Wenchuan M_s 8.0 earthquake

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 167-175页

作者： Cao Zhenzhong1.Hou Longqing2,Xu Hongmei2 and Yuan Xiaoming1.1. institute of Engineering Mechanics,{1. Earthquake Administration,Harbin 1.0080,{1. 2. East {1. institute of Technology,Fuzhou 344000,{1. institute of Engineering Mechanics China Earthquake Administration Harbin China East china {1. of Technology Fuzhou China institute of Engineering Mechanics Chinese Earthquake Administration Harbin China

In this paper,a distribution map of gravelly soil liquefaction that was caused by the Wenchuan M8.0 earthquake in china is proposed based on a detailed field investigation and an analysis of geological soil profiles. The geological background of the earthquake disaster region is summarized by compiling geological cross sections and borehole logs. Meanwhile,four typical liquefied sites were selected to conduct sample drillings,dynamic penetration tests (DPT),and shear wave velocity tests,to understand the features of liquefied gravelly soil. One hundred and eighteen (1.8) liquefied sites were investigated shortly after the earthquake. The field investigation showed:(1. sandboils and waterspouts occurred extensively,involving thousands of miles of farmland,1.0 villages,eight schools and five factories,which caused damage to some rural houses,schools,manufacturing facilities and wells,etc.; (2) the Chengdu plain is covered by a gravelly soil layer with a thickness of 0 m to 541.m according to the geological cross sections; (3) there were 80 gravelly soil liquefied sites in the Chengdu plain,shaped as five belt areas that varied from 20 km to 40 km in length,and about ten gravelly soil liquefied sites distributed within Mianyang area; and (4) the grain sizes of the sampled soil were relative larger than the ejected soil on the ground,thus the type of liquefied soil cannot be determined by the ejected soil. The gravelly soil liquefied sites are helpful in enriching the global database of gravelly soil liquefaction and developing a corresponding evaluation method in further research efforts.

关键词： gravelly soil liquefaction borehole soil profile geological cross section grain size distribution Wenchuan earthquake

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Distribution of molluscan remains in the sediment of the Chukchi Sea and its vicinity, the Arctic

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Acta Oceanologica Sinica 2003年第4期22卷 607-619页

作者： Gao Aiguo 1.2, Xu Fengshan3, Sun Haiqing 1.2, Li Lon1.1. First institute of Oceanography, State Oceanic Administration, Qingdao 266061.{1.. 2. Key Laboratory of Marine Sedimentology and Environmental Geology, State Oceanic Administration, Qingdao 266061.{1. 3. institute of Oceanology, Chinese academy of Sciences, Qingdao 266071.{1. First institute of Oceanography State Oceanic Administration Qingdao 266061 China institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Lab. Mar. Sedimentol./Environ. State Oceanic Administration Qingdao 266061 China

The result of an analysis of mollusca remains collected from the Chukchi Sea, Beaufort Sea and Bering Sea in the First Chinese National Arctic Research Expedition, from July to September, 1.99 is presented. Seventeen species of mollusca have been identified, which belong to two classes: Bivalvia and Gastropoda. The compositions of the mollusca are very simple. According to the distribution pattern two groups may be distinguished among molluscan species. The Pan-Arctic and circumboreal group comprises Nuculana pernula, ***, Nucula bellotii, Astarte montagui, Seripes groenlandicus, Macoma calcarea, M. moesta alaskana, Liocyrna fluctuosa, Mya pseudoarenaria and Turritella polaris. Three species, Cyclocardia crebricostata, Trichotrois coronata and Argobuccinum oregonense are components of the Pan-Arctic and Pacific boreal group. With regard to feeding habits, detritus feeders dominate. There are 7 species of detritus feeders, i.e., Nuculana pernula, N. radiata, Nucula bellotii, Macoma calcarea, M. moesta alaskana, Macoma sp. and Trichotropis coronata. Detritus feeders are dominant with regard to the numbers of species as well as to the frequency of occurrence. Macoma calcarea is the most abundant species.

关键词： Chukchi Sea Beaufort Sea Bering Sea molluscan remains

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