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Acute toxicity of DMAH to Oryzias latipes as modified by some influential factors

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Journal of Environmental Sciences 1997年第1期9卷 20-26页

作者： Zhu Jiang institute of Zoology,Chinese Academy of Sciences,beijing 100080,chinaLi Lixin beijing Municìpal Academy of Environmental Protection,beijing 100037,china institute of Zoology Chinese Academy of Sciences Beijing 100080 China beijing Munic. Acad. Environ. P. Beijing 100037 China

As a new insecticide,less information about the aquatic biological toxicity of DMAH [N-(2,4-dimethylphenyl)-N'-methylamidine hydrochloride]is *** 96h static bioassays were conducted with Oryzias latipes to assess the toxicity of DMAH and the influence of environ- mental *** results indicated that,at 23℃,the 24h,48h and 96h LC_(50)are 14.6 mg/L,13. 06 mg/L and 12.39 mg/L,respectively,the safe concentration(SC)of DMAH to Oryzias latipes is 1.16-1.32 mg/*** changes of temperature,pH value and hardness of water will significantly influence the toxicity of DMAH to fish.

关键词： DMAH[N-(2,4-dimethylphenyl)-N'-methylamidine hydrochloride] Oryzias latipes acute toxicity.

Fiducial intervals of restricted parameters and their applications

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Science china Mathematics 2005年第11期48卷 1567-1583页

作者： LI Xinmin, LI Guoying & XU Xingzhong College of Mathematics and information Sciences, Shandong University of Technology, Zibo 255049, china Academy of Mathematics and System Sciences, Chinese Academy of Sciences, beijing 100800, china Department of Mathematics, beijing institute of Technology, beijing 100801, china 1. College of Mathematics and information Sciences Shandong University of Technology 255049 Zibo China 2. Academy of Mathematics and System Sciences Chinese Academy of Sciences 100800 Beijing China 3. Department of Mathematics Beijing Institute of Technology 100801 Beijing China

In practice, the unknown parameters are often restricted. This paper provides a general method for constructing the fiducial intervals of the restricted parameters. Applying the general method, the fiducial intervals are constructed for the location (scale)parameters and the difference (ratio) of two locations (scales) in a location (scale) family of distributions. The frequency properties of these intervals are verified. For a variance components model, the fiducial intervals for the three parameters of common interest are obtained. Their frequency properties are investigated theoretically and computationally.

关键词： restricted parameter space,fiducial interval,frequency property,variance components

Unconformity-like Reflection Pattern under the Moho in the Sulu Area

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Continental Dynamics 1997年第1期 22-28页

作者： YANG Wencai (institute of Geology, Chinese Academy of geological Sciences (CAGS), beijing 100037,china)

When seismic exploration is carried out for finding oil/gas traps in a sedimentary basin, angular unconformity-like reflectors often appear in a seismic profile, indicating some promising structures such as pinchout. People usually think that the angular unconformity-like reflection pattern could occur only in a sedimentary basin within the upper crust because the pattern corresponds to a combination of a flat layer and some dipping layers, and they belong to different sedimentary sequences. In order to find optimal site for continental scientific drilling in the Dabie-Sulu ultra-high pressure metamorphic belt containing minerals such as coesite and micro-diamond, I have been in charge of geophysical investigations in these Proterozoic metamorphic ter- ranes of crystalline rocks. The investigation includes deep seismic reflection, magnetotelluric survey, gravity and magnetic studies, together with large-scale geological mapping on the surface. In the Shimen site located in southeast Shandong Province, East china, I have found a very clear angular reflection pattern, similar to those obtained by petroleum seismic exploration in sedimentary basins, appearing from 10.3 s to 13 s, right under the Moho discontinuity. This unusual and strange event from the uppermost mantle seems significant and might provide some clues for understanding the interaction between the crust and the mantle. Therefore I present the result here for further studies and worldwide comparison. I shall start with the basic geological settings of this area, then deal with the data acquisition and processing parameters as well as the deep seismic reflection sections to identify the deep angular unconformity-like pattern (see Fig. 4), finally, a brief discussion on interpretation of this type of reflection events.

关键词： deep seismic reflection mantle-crust interaction Sulu UHPM terrane East china

TWO TYPES OF XENOLITH—MANTLE XENOLITH AND CRUSTAL XENOLITH FOUND IN THE CENOZOIC VOLCANIC ROCKS FROM HOH XIL, NORTHERN TIBET PLATEAU

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地学前缘 2000年第S1期7卷 197-198页

作者： Wu Cailai,Yang Jingsui,Li Haibing,Shi Rendeng[WT5,5”BX](institute of Geology,Chinese Academy of geological Sciences,beijing 100037,china)

It is known that large amounts of Cenozoic high potassium volcanic rocks occur on the Tibetan plateau. The question is where do those high potassium magmas come from? Since the plateau is being compressed by subduction and collision from the surrounding continents,it is a puzzle for us what is the formational environment and tectonic setting of these volcanic rocks? In particular,what is the relationship between these special rocks and formation and uplift of the plateau? We recently carried out an investigation on these Cenozoic volcanic rocks in Hoh Xil,northern Tibetan plateau,including volcanic rocks in the Jingyuhu,Xiongyingtai and Shuangquanzi areas. In the region,some older lava flows occur as thick sheets with a flat surface and weathering crust; while some relatively younger lavas remain a relict volcanic cone or vent. Most of the relict cones are small (1 or close to 1,and mostly belonged to shoshonite\|trachyte association and some to ultra\|potassic rocks. The K\|Ar dating of whole rock and mica shows that the volcanism lasts from middle Miocene (15 47Ma) to Pleistocene (0 69Ma); they are 0 69Ma,13 77Ma and 15 47Ma in Jingyuhu; 11 05Ma,12 22Ma and 12 83Ma in Xiongyingai,; 1 58Ma,2 24Ma,5 23Ma,5 85Ma,8 20Ma,8 41Ma and 10 67Ma in *** types of xenolith and xenocryst were found in Jingyuhu and Xiongyingtai,i.e..,crustal xenolith and mantle xenocryst.

关键词： xenolith xenocryst shoshonite trachyte Cenozoic volcanic r ock Tibet Hoh Xil

Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 466-479页

作者： Geng Yuansheng, Liu Dunyi and Song Biaoinstitute of Geology, Chinese Academy of geological Sciences, 26 Baiwanzhuang,beijing 100037, china institute of Geology Chinese Academy of Geological Sciences 26 Baiwanzhuang Beijing 100037 China [?]Geng Yuansheng Born in January 1950 got a master degree at the Changchun College of Geology in 1981 long engaged in the study of Early Precambrian geology and metamorphic petrology now research professor at the institute of Geology Chinese Academy of Geological Sciences.

Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2868-2932 Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2761 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2650 Ma, resulting in crustal thickening. The thickening was enhanced at 2561-2503 Ma by the widespread intrusions of granodioritic magma. In the period of 2477-2461 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 2300 Ma ago, and finally pink granite intrusions at 2144-2087 Ma resulted in the formation of a granite zone.

关键词： geological event Early Precambrian geochronology granulite northwestern Hebei

china Continental Conductive Layers and Its Relationship with Basin Evolution

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Journal of Earth Science 1997年第1期16卷 16-20页

作者： Xu Changfanggeological institute, State Seismological Bureau of china, beijing 100029

? This paper plots out two deep distribution maps of the china continental crustal and upper mantle conductive layers, and discusses the origin of two kinds of conductive layers, based on the results of the magnetotelluric(MT) sounding research made by Chinese scientists in the last two decades. The MT prospecting shows that the conductive layers possibly exist in upper mantle and middle-lower crust in the Mesozoic and Cenozoic stretching basins, and they coincide with the uplifting of two kinds of conductive layers. These characteristics help to illustrate the deep dynamic settings that control the basin evolution. 

关键词： crustal conductive layer basin evolution.

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , institute of Atmospheric Physics , Chinese Academy of Sciences , beijing 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083, china 3. The Center of information Science , Peking University, beijing 100871, china 4. Open Laboratory of Visual information Processing , institute of Biophysics , Chinese Academy of Sciences , beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of information Science Peking University Beijing China Open Laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Himalayan Tectonic Evolution in the East Asian Peri-Pacific Region

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 233-246页

作者： Cui Shengqin Li Jinrong institute of Geomechanics, Chinese Academy of geological Scinences, beijing Fei Zhenbi institute of Geornechanics Chinese Academy of Geological Scinences Beijing

This paper summarizes the Late Palaeozoic. Indosinian and Yanshanian palaeotectonic settings in theperi-Pacific region of East Asia. On that basis, the Himalayan crustal movement in the region is divided intothe early and late tectonic stages and two principal tectonic phases. From the ocean to the continent, 5 giganticHimalayan formation-deformation belts are distinguished; they are the Northwest Pacific trench-island arcbelt. the Northwest Pacific marginal sea basin bell. the East china Sea-northern South china Seacontinental-shelf down-faulted belt. the East Asian epicontinental rift belt. and the East Asian intracontinentalrift belt. The Early and Late Himalayan tectonic evolution is dealt with. Finally the state of the Himalayan re-gional stress field and its evoution in the region are discussed. It is considered that the mechanism of their for-mation is closely related to the continent-ocean and surface-deep earth interaction.

关键词： Asia

RST transforms resistant image watermarking based on centroid and sector-shaped partition

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Science china(information Sciences) 2012年第3期55卷 650-662页

作者： ZHAO Yao1,2*, NI RongRong1,2* & ZHU ZhenFeng1,2* 1institute of information Science, beijing Jiaotong University, beijing 100044, china 2beijing Key Laboratory of Advanced information Science and Network Technology, beijing 100044, china 1. institute of information Science Beijing Jiaotong University Beijing 100044 China2. Beijing Key Laboratory of Advanced Information Science and Network Technology Beijing 100044 China

A novel digital watermarking scheme featuring centroid-based sectoring is proposed in this paper. To get higher robustness against geometric attacks, such as rotation, scaling, and translation (RST), a delicate synchronization mechanism was developed and incorporated into the proposed approach. During the process of watermark embedding, the original image was partitioned into sectors based on the image centroid. Synchronization information as well as the message bits is then embedded into these sectors. With the help of the centroid-based sectoring and synchronization information, the proposed approach is capable of restoring the correct sectoring even if it has experienced severe geometric distortion. This attribute ensures the correct recovery of embedded watermarks and contributes to the robustness of the proposed scheme. A series of experiments have been conducted to verify the feasibility and effectiveness of the proposed approach. Experimental results show that the proposed scheme possesses good robustness against RST attacks and considerable robustness against other common image processing attacks.

关键词： digital watermarking geometrical transform attacks RST transforms