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Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, guizhou, south china

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Progress in Natural Science:Materials International 2005年第8期15卷 708-712页

作者： YANG Xinglian 1,2., ZHAO Yuanlong2. WANG Yue2.and WANG Pingli2.1. Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. institute of Resource and Environment, guizhou university, guiyang 550003, china) Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China. institute of Resource and Environment Guizhou University Guiyang 550003 China

Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new information for understanding early evolution and radiation of sponge animals.

关键词： sponges Cambrian Niutitang Formation guizhou china.

MODULATED STRUCTURES AND ORDERING STRUCTURES IN ALLOYING AUSTENITIC MANGANESE STEEL

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 148-152页

作者： L. He, Z.H. Jin and J.D. Lu (Department of Metallurgical Engineering, guizhou university of technology, guiyang 550003,{2.) (institute of Material Science and Engineering, Xi’an Jiaotong university,Xi’an 710049,{2.) Dept. of Metall. Eng. Guizhou Univ. of Technol. Guiyang 550003 China

The microstructure of Fe-10Mn-2.r-1.5C alloy has been investigated with transmission electron microscopy and X-ray diffractometer. The superlattice diffraction spots and satellite reflection patterns have been observed in the present alloy, which means the appearance of the ordering structure and the modulated structure in the alloy. It is also proved by X-ray diffraction analysis that the austenite in the alloy is more stable than that in traditional austenitic manganese steel. On the basis of this investigation, it is suggested that the C-Mn ordering clusters exist in the austenitic manganese steel and the chromium can strengthen this effect by linking the weaker C-Mn couples together, which may play an important role in work hardening of the austenitic manganese steel.

关键词： Aging of materials Austenite Crystal structure Manganese alloys Microstructure

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Sponge spicules in phosphorites of the Early Cambrian Gezhongwu Formation,Zhijin,guizhou

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Progress in Natural Science:Materials International 2004年第10期14卷 56-62页

作者： YANG Ruidong 1 ,QIAN Yi 2.,ZHANG Jie 1 ,ZHANG Weihua 1 ,JIANG Lijun 1 and GAO Hui 1 (1.guizhou university of {2.,guiyang550003,china 2.institute of Geology and Paleontology,Chinese Academy of Sci-ences,Nanjing2.0008,china) guizhou Univ Technol Guiyang 550003 Peoples R China Chinese Acad Sci Inst Geol & Palaeontol Nanjing 210008 Peoples R China

Phosphorites occurring at the bottom of the Cambrian system contain abundant small shelly fossils,which are the prod-uct of the first episode of life explosion in the *** was previously reported that the small shelly fossils are dominated by hy-olithids,olivooids,zhijinitids,conodontomorphs,yubelichitids,camenitids and algae,with minor amounts of sponge *** amounts of sponge spicules,diverse in form,have been found for the first time in the Gezhongwu Formation phosphorites at Shixing,Zhi-jin County,guizhou Province,of which such spicules as diaxon-triactins,diaxon-tetractins,pentaxon-pentactins and hexon-hexactins ac-count for30%.These spicules constitute the sponge clastic phosphorites made up of sponge ***,it is also expected that the radiation and diversity of sponge animals started as early as in the earliest Early *** and burying environment of sponge animal are discussed in the paper.

关键词： sponge animal Gezhongwu Formation Early Cambrian guizhou

Speciation of the genus Arthricocephalus Bergeron, 1899 (Trilobita) from the late Early Cambrian and its stratigraphic significance

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Progress in Natural Science:Materials International 2006年第6期16卷 614-623页

作者： YUAN Jinliang, ZHAO Yuanlong and YANG Xinglian (Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china College of Resource and Environment of{2. university, guiyang 550003, china) [a] Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China [b] College of Resource and Environment of guizhou university Guiyang China

The genus Arthricocephalus Bergeron, 1899 is revised, and Halipanktos Balker & Peel, 1997 is suggested here as a senior synonym. The subgenus Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974 is considered as a separate genus. Of the 2. previously assigned species of Arthricocephaius (Arthricocephalus) Bergeron, 1899, Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974, Arthricocephalus (Euarthricocephalus) Ju, 1983 are lumped into eight species. The speciation trend of Arthricocephalus and Arthricocephalites is demonstrated based on their stratigraphic occurrences. It not only enhances the resolution of the biostatigraphic zonation in the uppermost Lower Cambrian, but also represents a potential candidate to define the Duyunian stage. The base of the stage is suggested at the first appearance datum (FAD) of Arthricocephalus chauveaui Bergeron, 1899 within the evolutionary lineage from Ar. jiangkouensis Yin in Yin & Li, 1978 to Ar. chauveaui in a global scale.

关键词： late Early Cambrian Duyunian stage speciation of Arthricocephalus and Arthricocephalites biostratigraphy.

STUDY ON CORROSION RESISTANCE AND STRENGTHENING OF TITANIUM-CONTAINED COAT FOR BRUSH PLATING

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材料保护 1992年第8期 4-10页

作者： Deptartment of Chemistry guizhou university, {2., china (55002.) Shi Hongyun Fan Shourong Wang Yibo Yao Ping Zhang Yunqian guizhou Mechanical institute, {2., china (550003) Du Zhangyin Li Guangyan

Under brush plating the behaviour of the electrodeposition of metal titanium and the prescriptions of brush plating solution contaning titanium have been studied systematically in this paper. Based on this study, the four kinds of the prescriptions A,B,C and D are put forward. The properties of both coats for the solution A and B have been determined all-sidely. The result shows A and B both meet the stipulated technical requirements and have the following advantages :1. Their hardness can basically keep constant within 500℃ and increase slightly, which displays clear superiority to that of the brush plating solution High-speed Nickel, Nickel-Tungsten D used widely in china.2. Their corrosion resistance is good. The soaking test in 30% NaOH, 2.% H;SO;, man-made seawater and organic acid atmosphere test show their corrosion resistance is fairly good; besides, salt spray test is OK. The concerned factories have been interested in those good properties and begun to use them. We consider that both coats containing titanium may replace stainless steel and some noble metals, Based on microstructure analyses for the above coats, we confirm that some amorphous solid exists in both coats containing titanium, and the crystallizing temperature is between 500～550℃.

关键词： STUDY ON CORROSION RESISTANCE AND STRENGTHENING OF TITANIUM-CONTAINED COAT FOR BRUSH PLATING Ni 材料保护

New data regarding acritarch biostratigraphy from the Early-Middle Cambrian Kaili Formation in Chuandong,guizhou Province,china

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Progress in Natural Science:Materials International 2009年第1期19卷 107-114页

作者： Leiming Yin a,Ruidong Yang b,Jin Peng c,Fanfan Kong a a Nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 2.0008,china b College of Resource and Environment of{2. university,guiyang 550003,china c Department of Sciences of Nanjing university,Nanjing 2.0093,china [a]Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China [b]College of Resource and Environment of Guizhou University Guiyang 550003 China [c]Department of Sciences of Nanjing University Nanjing 210093 China

Previous studies had evaluated acritarchs from the Balang and Pingzhai sections of the Early-Middle Cambrian Kaili Formation in east guizhou,*** results of these studies suggest that the acritarchs in these sections have potential biostratigraphic *** recently,34 samples collected from 83 m lower part of the Lower-Middle Cambrian Kaili Formation in the Jianshan section of Chuandong,guizhou Province were prepared for palynological *** of these samples revealed a distinct change in the acritarch assemblages at the bed,which was approximately 46 m above the bottom of the Kaili *** findings suggest a boundary represented by an important alteration of the ecological *** addition,the position of the acritarch biostratigraphic change is somewhat higher than the boundary between Cambrian Series 2.and Series 3 based on trilobites found in the same *** indicates that the distinct change in acritarch assemblages is similar to the change in trilobite assemblages that occurs around the boundary between Cambrian Series 2.and Series ***,acritarch biostratigraphy can provide data that can be used to define the base of Cambrian Series 3 in this region,and possibly worldwide.

关键词： Acritarchs Lower-Middle Cambrian Kaili Formation Jianshan section Chuandong

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2. PENG Shanchi~ 2.3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of guizhou university,{2., china 2. Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing institute of Geology and Palaeontology, Nanjing 2.0008, china 4. Department of Geological Science, Ohio State university, Columbus, OH 432.0, USA 5. institute of Geochemistry, Chinese Academy of Sciences, guiyang 550002. china) College of Resource and Environment of guizhou university Guiyang 550003 China Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from guizhou, china and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2.02. and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2.03 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12.segments, and a small pygidium that bears 2.3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962.or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian guizhou china.

Local segment-shared protection based on source egress gateway selection for multi-domain optical mesh networks

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Science china(Information Sciences) 2011年第2期54卷 227-235页

作者： ZHANG ShengFeng1,3, PENG YunFeng1,2. DU Shu1, YANG XiaoLong1,2.& LONG KePing1,2.1Research Center for Optical Internet and Mobile Information networks, university of Electronic Science and {2. of china, Chengdu 611731, china 2.5} of Advanced network {2. and New Serives (ANTS), university of Science and {2. Beijing, Beijing 100083, china 3Research Center for Optical Internet networks, Chongqing university of Posts and Telecommunications, Chongqing 400065, china 1. Research Center for Optical Internet and Mobile Information networks University of Electronic Science and Technology of China Chengdu 611731 China3. Research Center for Optical Internet Networks Chongqing University of Posts and Telecommunications Chongqing 400065 China2. Institute of Advanced Network Technology and New Serives (ANTS) University of Science and Technology Beijing Beijing 100083 China

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

关键词： survivability optical mesh networks multi-domains multiple failures segment-shared protection

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用压缩蠕变试验研究高填方体沉降变形

西南交通大学学报 2004年第6期39卷 749-753页

作者：刘宏李攀峰张倬元贵州工业大学省喀斯特环境与地质灾害防治重点实验室贵州贵阳550003 成都理工大学工程地质研究所四川成都610059

以九寨黄龙机场104m高填方体为工程背景,研究了砂砾石填料压缩蠕变试验与高填方体的相似条件.研究表明,刚性侧限的压缩蠕变试验与大面积凹谷中的高填方体具较好的相似性,两者可近似为等应力状态,但试验得出的高填方体压缩沉降量较实测... 详细信息

以九寨黄龙机场104m高填方体为工程背景,研究了砂砾石填料压缩蠕变试验与高填方体的相似条件.研究表明,刚性侧限的压缩蠕变试验与大面积凹谷中的高填方体具较好的相似性,两者可近似为等应力状态,但试验得出的高填方体压缩沉降量较实测值稍小.此外,初始压实度决定了砂砾石填料的压缩变形特性,初始压实度为97.4%的砂砾石填料的压缩变形过程具对数函数特征,而初始压实度大于98.7%的砂砾石填料的压缩变形过程则以线性函数特征为主.

关键词：高填方体压缩蠕变试验沉降

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