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Pioneer organisms after F-F mass extinction in Dushan region,guizhou Province,and their significance in establishing new ecosystem

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Science china Earth Sciences 2006年第5期49卷 449-460页

作者： WANG Yue1, 2. WANG Xunlian1 & SHI Xiaoying1 1. school of Earth Sciences and resources, {2. university of Geosciences, Beijing 100083, {2. 2. school of resources and environment, guizhou university, guiyang 550003. china school of Earth Sciences and resources China University of Geosciences Beijing China school of resources and {2. Guizhou University Guiyang China

After mass extinctions, most areas became “ecologically barren areas” lacking or even without ecosystem over an extensive region. Studying the pioneer organisms and the reconstruction process of a new ecosystem in the “ecologically barren area” is very important for revealing the evo- lution after bio-mass extinctions. In the Dushan region, guizhou Province, china, the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian (F-F) mass extinction. The pioneer organisms and pathfinders in the “ecologically barren areas” are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface. The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex, and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces. Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem. This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary. In the Dushan area, only the recovery intervals have been identified for the Famennian body fossils, with no eminent radiation interval recognizable due to the Devonian-Carboniferous (C-D) mass ex- tinction. However, both the recovery and radiation intervals may be clearly recognized in the Famen- nian trace fossils based on their conformation and diversity. The evolution and diversification of the trace fossils in the “ecologically barren area” is considered to have played a role of necessary foun- dation for the recovery of body fossils in the ecological chain. With the gradual disappearance of the unfavourable {2. factors resulting in the F-F mass extinction, a new ecosystem was reconstructed in the “ecologically barren area” through a three-

关键词： pioneer organisms, reconstruction of ecosystem, trace fossils, F-F mass extinction, Later Devonian, Dushan region, guizhou Province, china.

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Two-Sublattice Thermodynamic Model on Carbonitride Precipitation in Microalloyed Steels Bearing Nb-V-Ti

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Journal of Iron and Steel Research International 2011年第S1期18卷 271-277页

作者： XIANG Song 1,3,LIU Guo-quan 2.(1.school of Materials and Metallurgy,guizhou {2.,guiyang 550003.guizhou,china 2.school of Materials Science and Engineering,{2. of Science and Technology,Beijing,Beijing 100083,china 3.The Key Laboratory for Mechanical Behavior and Microstructure of Materials,guizhou Province,guiyang 550003.guizhou,china) guizhou Univ Sch Met & Mat Guiyang 550003 Guizhou Peoples R China Key Lab Mech Behav & Microstruct Mat Guiyang 550003 Guizhou Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

Based on the two sublattice model of the regular solution,one being metal atom sublattice and another being interstitial atom sublattice,a thermodynamic model for the precipitates of niobium carbonitride,vanadium carbonitride and titanium carbonitride was established to study the starting-temperature of precipitates and the austenite compositions at given temperature in a low carbon *** calculation results show that starting-temperature of the precipitation of niobium carbonitride,vanadium carbonitride and titanium carbonitride are 1100℃,92.℃ and 1340℃,respectively,the mole fraction of carbonitride precipitates is 8.65×10-4 in the 0.053C-0.002.N-1.2.Mn-0.008S-0.031Al-0.046Nb-0.008Ti0.02.V-Fe *** the N content is from 0.002.% to 0.0056%,the starting-temperature of the precipitation of the titanium carbonitride changes from 1340℃ to 1430℃.And the C content is from 0.053% to 0.07%,the startingtemperature of the precipitation of the titanium carbonitride hardly changes,but the atomic fraction of niobium in the carbonitride obviously increases.

关键词： microalloyed steel carbonitride precipitation two sublattice model thermodynamics

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Accountability Analysis of Electronic Commerce Protocols by Finite Automaton Model

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Wuhan university Journal of Natural Sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2., Zhang Huan-guo 1 1. school of Computer, Wuhan university, Wuhan 430072. Hubei, {2. 2. Institute of Network Technology, guizhou university of Technology, guiyang 550003. guizhou, {2. school of Computer Wuhan University Wuhan Hubei China Institute of Network Technology Guizhou University of Technology Guiyang Guizhou China

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: Supported by the National Natural Science Foundation of china (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952.), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

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Effect of Nd_2.e_(14)B/α-Fe Nanocomposite Permanent Magnets with a Combined Co and Nb Additions

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Journal of Wuhan university of Technology(Materials Science) 2009年第5期24卷 725-727页

作者：马瑞 school of Materials Science and Metallurgy Engineering Guizhou University

Influence of Co＋Nb on the Nd8Fe82.o3Nb1B6 nanocomposite magnets was investigated by adding Co element combined with Nb element. Results show that the high temperature stability of two phases is increased. Adding Co＋Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic properties of the alloy. The optimal magnetic properties are Br=1.14 T, Hcj=32. kA/m, （BH）max=109.3 kJ/m^3

关键词： nanocomposite permanent magnets glass forming ability exchange coupling ability magnetic properties

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Recent advances in functional utilisation of environmentally friendly and recyclable high-performance green biocomposites: A review

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Chinese Chemical Letters 2024年第4期35卷 73-85页

作者： guiyang Zheng Xuelian Kang Haoran Ye Wei Fan Christian Sonne Su Shiung Lam Rock Keey Liew Changlei Xia Yang Shi Shengbo Ge Co-Innovation Center of Efficient Processing and Utilization of Forest resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China school of Textile Science and Engineering&Key Laboratory of Functional Textile Material and Product of Ministry of Education Xi'an Polytechnic UniversityXi'an 710048China Department of Bioscience Arctic Research Centre(ARC)Aarhus UniversityFrederiksborgvej 399PO Box 358DK-4000 RoskildeDenmark Sustainability Cluster School of EngineeringUniversity of Petroleum&Energy StudiesDehradunUttarakhand 248007India Higher Institution Centre of Excellence(HICoE) Institute of Tropical Aquaculture and Fisheries(AKUATROP)Universiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Center for Transdisciplinary Research Saveetha Institute of Medical and Technical SciencesSaveetha UniversityChennai 600072India NV Western PLT Georgetown 10400PenangMalaysia Aerospace Kaitian environmental Technology Co. Ltd.Changsha 410000China Hunan Hongsen Novel Material Technology Co. Ltd.Yiyang 413407China

Humans have relied on biomass for survival and development since the Stone Age. All aspects of human needs for materials are covered by tools, fuel, and buildings. Nowadays, metals and petroleum-based materials are widely used in highly developed industries. Unfortunately, environmental contamination and the loss of natural resources have led to the reemergence of biomass resources as efficient and sustainable energy sources. Notably, simple and direct applications can no longer meet the demand for functionalization, high performance of materials and construction materials. Therefore, it is imperative to modify biomass and combine its utilisation to produce functionalization and high performance materials. For example, construction materials with superior mechanical properties and water resistance can be produced by reinforcing fibres to facilitate crosslinking. Water-oil separation or adsorption effects of hydrogels and aerogels are determined by the porosity and lightness of biomass, biocomposite conductor is prepared by chimaeric conductive material. Here, we review the approaches that have been taken to devise an environmentally friendly yet fully recyclable and sustainable functionalised biocomposites from biomass and its potential directions for future research.

关键词： Biocomposite Renewable Sustainability Advanced functional material Pollution mitigation

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Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate school of guizhou university, {2. 55002., china Nanjing Institute of Geology and Mineral resources, Nanjing 2.0016, china Geological Survey of No. 3 Geological Party, Xinjiang, Kurle 841000, china) Postgraduate school of guizhou university Guiyang 550025 China Nanjing Institute of Geology and Mineral resources Nanjing 210016 China Geological Survey of No. 3 Geological Party Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3-1. 4 mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

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Cambrian trilobite Ovatoryctocara granulata Tchernysheva,1962.and its biostratigraphic significance

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Progress in Natural Science:Materials International 2009年第2期19卷 213-221页

作者： Jinliang Yuan a,Yuanlong Zhao b,Jin Peng b,Xuejian Zhu a,Jih-pai Lin c a Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,East Beijing Road 39,Nanjing 2.0008,china b College of Resource and environment Science,{2. university,guiyang 550003.china c school of Earth Sciences,Ohio State university,Columbus,OH 432.0,USA Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences East Beijing Road 39 Nanjing 210008 China College of Resource and environment Science Guizhou University Guiyang 550003 China school of Earth Sciences Ohio State University Columbus OH 43210 USA

The genus Ovatoryctocara Tchernysheva,1962.and its key species Ovatoryctocara granulata Tchernysheva,1962.are revised. Ovatoryctocara granulata occurs near the base of the Ovatoryctocara Zone and ranges up into the lower portion of the Kounamkites Zone in the Siberian Platform. O. granulata also appears in southeastern guizhou,South china,but O. granulata in northern Greenland may represent an indefinite species. Specimens of Ovatoryctocara from Newfoundland cannot be identified to species level. Specimens includ-ing two cranidia and three pygidia from the lower part of the Aoxi Formation at Yaxi Village,Shizhu Town,eastern Tongren,north-eastern guizhou,were previously assigned to O. granulata,which is now reassigned as a new species O. yaxiensis sp. nov. It bears the following main features: glabella club-shaped,slightly expanded medially,with four pairs of lateral furrows,of which S1-S3 are trian-gular pits,S4 is shallow,connecting with axial furrow; shorter palpebral lobe situated a little anterior to the midway of facial suture across the fixigenae,longer posterolateral area (exsag.); semielliptical pygidium consisting of seven axial rings with a terminal piece and with eight pairs of marginal tips giving a sawtooth-like shape of the lateral margins in dorsal view. Although O. granulata is a widely distributed species,the FAD of O. granulata,for a global stage boundary,still has some disadvantages. First,its distribution is not as wide as that of Oryctocephalus indicus (Reed,1910). Second,specimens of O. granulata are common only in Siberia. Third,the strati-graphic range of the species has not been studied in detail in all continents. Fourth,O. granulata is relatively small and easily affected by post-burial distortion. Last but not least,there exists obviously a facies change between the Ovatoryctocara Zone (lower Amgan Stage; deeper water facies) and the underlying Anabaraspis splendens Zone (Toyonian Stage; shallow water facies) in Siberian Platform. Nev-ert

关键词： Trilobites Ovatoryctocara granulata Tchernysheva,1962 Cambrian Biostratigraphy

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Indigenous Knowledge of Natural Resource Management and Population Control for Dong Ethnic Group in guizhou Province

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Chinese Journal of Population,resources and environment 2010年第3期8卷 11-16页

作者： Yuan Juanwen1,2. Wu Quanxing3 1. school of resources and {2.al Management, guizhou College of Finance and Economics, guiyang guizhou 550004, china 2. Sociology of Consumers and Households, Wageningen university and Research, Wageningen, 6700 KN, The Netherlands 3. Cultural Institute, Qiandongnan Miao and Dong Autonomous Prefecture, Kaili guizhou 556000, china school of resources and {2.al Management Guizhou College of Finance and Economics Guiyang Guizhou 550004 China Sociology of Consumers and Households Wageningen University and Research Wageningen 6700 KN The Netherlands Cultural Institute Qiandongnan Miao and Dong Autonomous Prefecture Kaili Guizhou 556000 China

Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional knowledge of Dong ethnic people in resource management and population control, including traditional resource management, traditional medicinal knowledge and village regulations in Zhanli Village in Southeast guizhou Province. The research methods include key informant interview, group discussion, participant observation and secondary data collect- ing. The results show that Zhanli villagers try their best to utilize indigenous knowledge to manage the natural resources and keep the stable population to make themselves live in a sustainable way. Indigenous knowledge plays an important role in managing their limited natural resources and keeping the population stable under an excellent condition. Zhanli villagers employ indigenous knowledge to manage natural resources and use local herbs to control the population. Village regulation terms significantly influence villagers’ awareness in resource management and birth control. Women play the chief role in employing indigenous knowledge in weaving as well as medicinal knowledge in birth control, and these kinds of knowledge are passed down through the female line. However, the inheritance style of traditional knowledge is decreasing. Indig- enous knowledge plays an important role in the sustainable development of this village, which gives implications for development practices to involve indigenous knowledge to achieve sustainable development.

关键词： traditional knowledge natural resource management population control Dong ethnicity guizhou

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SIR-2.地质雷达在隧道超前预报中的常见问题与分析

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施工技术 2010年第S1期39卷 246-248页

作者：常铮贵州大学资源与环境工程学院贵州贵阳550003

结合贵州省某三车道小间距隧道中的应用实例,以美国GSSI公司SIR-2.型地质雷达为例,对隧道超前预报中的常见问题及解决办法进行了一些探讨。

关键词： SIR-2.地质雷达隧道超前预报地质灾害

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Relationship Between Vegetation Restoration and Soil Microbial Characteristics in Degraded Karst Regions: A Case Study

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Pedosphere 2011年第1期21卷 132-138页

作者： WEI Yuan YU Li-Fei ZHANG Jin-Chi YU Yuan-Chun D. L. DEANGELIS school of resources and {2.al Management Guizhou College of Finance and Economics Guiyang 550004 (China) College of Forestry Guizhou University Guiyang 550025 (China) College of Forest and environment Nanjing Forestry University Nanjing 210037 (China) Department of Biology University of Maimi P. O. Box 249118 Coral Gables FL 33124 (USA)

The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last *** an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern guizhou Province,*** community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial *** results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land *** trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2. decreased with vegetation restoration,and remained at a constantly low level in the arboreal community *** of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional *** utilization of specific substrate guilds was highest in the arboreal community *** component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three *** conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2.thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.

关键词： basal respiratory community level physiological profile functional diversity metabolic quotient microbial biomass C

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