972 resultados para southern China


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The taxonomic problem of the cyprinid species of genus Spinibarbus, occurring in southern China and northern Vietnam, was resolved on the basis of molecular and morphological analyses. Spinibarbus caldwelli and Spinibarbus hollandi have a smooth posterior edge of the last unbranched dorsal fin ray among species in the genus. Spinibarbus caldwelli is currently regarded as a junior synonym of S. hollandi because of ambiguities in diagnostic characters. In this article, 11 mtDNA cytochrome b sequences of Spinibarbus specimens were analyzed together with Barbodes gonionotus and Puntius conchonius as outgroups. Our results showed that specimens identified as S. hollandi from Taiwan were different from those from the Asian mainland at a high level of genetic divergence (0.097-0.112), which is higher than that between the two valid species, S. sinensis and S. yunnanensis ( 0.089), and suggested that Taiwan specimens should be considered as a different species from the Asian mainland one. In a molecular phylogenetic analysis, the sister-group relationship between Taiwan specimens and the Asian mainland specimens was supported strongly by a high confidence level ( 100% in bootstrap value). Further analysis of morphological characters showed that overlap of diagnostic characters is much weaker than previously suggested. Taiwan specimens had 8 branched rays in the dorsal fin, whereas those from the mainland had almost 9-10. The molecular and morphological differences suggest S. caldwelli to be valid. The molecular divergence shows the genetic speciation of S. hollandi and S. caldwelli might have occurred 5.6-4.9 million years ago; the former could be a relict species in Taiwan, and the latter dispersed in the Asian mainland.

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Thirteen species of Limnodriloidinae (Tubificidae) are recorded from marine and brackish-water habitats of Hainan Island, southern China, including 11 species of Doliodrilus and two species belonging to Limnodriloides . Eight species are new to science: D. bisaccus sp. n. (types from Japan), D. longidentatus sp. n. (types from Hong Kong), D. ciliatus sp. n., D. adiacens sp. n., D. fibrisaccus sp. n. (also from Fiji), D. brachyductus sp. n., D. bidolium sp. n. and D. chinensis sp. n. In addition, material of D. puertoricensis Erseus and Milligan, 1988, from New Caledonia, is briefly described. This study shows that Doliodrilus is unexpectedly species-rich in Asian seas, in particular, around Hainan. Including an unnamed species from this island, the known members of this genus increase from three to 12.

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Wu-Han Xiao, Jian-Guo Wang and Lian-Xiang Li (2002) Taxonomic studies of parasitic nyctotherans from Chinese Anura amphibians III. Wichtermania. Zoological Studies 41(1): 69-76. This paper describes 6 new species belonging to the genus Wichtermania from Anura amphibians distributed in southern China. The 6 species are Wichtermania multigranularis sp. nov., W. oviformis sp. nov., W vesiformis sp. nov., W. reticulatis sp. nov., W granuliformis sp. nov., and W obliquoides sp. nov. The characteristics for diagnosis of the 6 new species are described in this paper.

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Lian-Xiang U, Jian-Guo Wang and Wu-Han Xiao (2002) Taxonomic studies of parasitic nyctotherans from Chinese Anura amphibians IV. Spirocytopharynxa gen. nov. and Macrocytopharynxa gen. nov. Zoological Studies 41(1): 77-84. This paper describes 2 new genera and 5 new species of nyctotherans from Anura amphibians distributed in southern China. Based on the composition of the upper and bottom flaps, the number and position of sutural lines, the length of the oral groove, and the morphology and position of the end of the cytopharynx, the adoral zone of the membranelle (AZM), and the macronucleus, two new genera were established. The 3 new species, Spirocytopharynxa sinensis, S. guangxiensis, and S. quadranus, belong to the new genus Spirocytopharynxa, Another 2 species, Macrocytopharynxa (Nyctotheroidae Nie, 1932) pyriformis n. comb. and M. lingchuanensis n. sp., belong to the new genus Macrocytopharynxa. The characteristics for diagnosis of the 2 new genera and 5 new species are described in this paper.

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1140 bp of cytochrome b gene were amplified and sequenced from 14 species of primitive cyprinid fishes in East Asia. Aligned with other ten cytochrome b gene sequences of cyprinid fish from Europe and North America retrieved from Gene bank, we obtained a matrix of 24 DNA sequences. A cladogram was generated by the method of Maximum likelihood for the primitive cyprinid fishes. The result indicated that subfamily Leuciscinae and Danioninae do not form a monophyletic group. In the subfamily Danioninae, Opsariichthys biden and Zacco platypus are very primitive and form a natural group and located at the root. But the genera in subfamily Danioninae are included in different groups and have not direct relationship. Among them, Aphyocypris chinensis and Yaoshanicus arcus form a monophyletic group. Tanichthys albonubes and Gobiocypris rarus have a close relation to Gobioninae. The genus Danio is far from other genera in Danioninae, In our cladogram, the genera in Leuciscinae were divided into two groups that have no direct relationship. The genera in Leuciscinae distributed in Europe, Sibera and North America, including Leuciscus, Rutilus, Phoxinus, N. crysole, Opsopoeodus emilae, form a monophyletic group. And the Leuciscinae in southern China including Ctenopharyngodon idellus, Mylopharyngodon piceus, Squalibarbus and Ochetobius elongatus have a common origination.

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角蟾科(Megophryidae)是以角蟾属(Megophrys Kuhl and Van Hasselt, 1822)为模式属而建立的,隶于无尾目(Anura),变凹型亚目(Anomocoela)。角蟾科包括2 亚科11 属142 种,分布于东洋界,从巴基斯坦、中国西部向东直到菲律宾和苏达群岛;中国有9 属75 种分布于华中和华南地区。角蟾科被认为是原始的两栖动物之一,其分类学、系统学、生态学、动物地理学的研究均深受中外科学家的瞩目。近年来,通过形态学、古生物学、细胞学、生态学、支序系统学的研究,角蟾科的分类与系统学研究取得了较大进展。与成体形态和分子系统学研究结果相比较,蝌蚪的研究存在更多的问题和挑战,尚需深入研究:(1)角蟾科蝌蚪的形态多样性分析;(2)角蟾科的系统发育关系与蝌蚪的演化,以及口漏斗的起源;(3)角蟾科蝌蚪表型分化与栖息环境和觅食行为的适应演化。针对上述问题,本文对角蟾科9 属30 种蝌蚪的形态特征,包括外部宏观形态和口器外部结构特征、口器内部显微结构、唇齿和角质颌的亚显微结构作了深入细致、多层次的比较研究;通过12s rRNA 和cytochrome b 基因构建最大简约树,采用贝叶斯系统发育进行分析,蝌蚪型的演化采用祖先性状的重建方法分析;得到如下结论:1)初步将角蟾科蝌蚪分为4 种类型;并且建立了2 种新的角蟾科蝌蚪类型。A 型:拟髭蟾型蝌蚪,该型蝌蚪包括拟髭蟾属、髭蟾属、齿蟾属和齿突蟾属的物种;B 型:新类型,掌突蟾型蝌蚪,该型蝌蚪在本文中包括掌突蟾属、小臂蟾属的物种;C 型:新类型,短腿蟾型蝌蚪,一种特化类型,该型蝌蚪在本文中仅包括短腿蟾属的物种;D 型:角蟾型蝌蚪,该型蝌蚪在本文中包括无耳蟾属、小口拟角蟾属和异角蟾属的物种。2)对角蟾科的分类进行了修订:(1)支持角蟾科两个亚科的分类系统;(2)角蟾亚科包括拟角蟾属、异角蟾属、无耳蟾属和短腿蟾属;该亚科形态差异小,系统学关系比较复杂,暂不作族级分类的再划分;(3)拟髭蟾亚科分为2 个族:拟髭蟾族,该族物种具有类型A 的蝌蚪,包括4 个属:拟髭蟾属、髭蟾属、齿蟾属、齿突蟾属;掌突蟾族,该族物种具有类型B 的蝌蚪,包括2 个属:掌突蟾属和小臂蟾属。3)结合分子系统进化关系探讨了4 种蝌蚪类型的演化。(1)角蟾科蝌蚪的最近共同祖先来自于一类具有拟髭蟾型蝌蚪性状的蝌蚪;(2)掌突蟾型蝌蚪和角蟾亚科的蝌蚪是由具有拟髭蟾型蝌蚪性状的祖先蝌蚪分别演化而来;(3)短腿蟾型蝌蚪是角蟾型蝌蚪的一种特化类型;(4)外群蝌蚪具有与拟髭蟾型蝌蚪相似的性状,进一步印证了类拟髭蟾型蝌蚪是角蟾科蝌蚪的最近共同祖先的假说;(5)具有口漏斗的蝌蚪类型是由不具口漏斗的蝌蚪类型演化而来,在角蟾科中口漏斗是一种衍生性状。4)分析了角蟾科四种蝌蚪类型与栖息环境的适应演化。(1)角蟾科蝌蚪的口部和体形的变化反映了该科蝌蚪由缓流向类似静水生境的回水凼的渐变式适应,角蟾科蝌蚪的形态显示了多方面的适应变化;(2)随着蝌蚪类型由A 向D的演化,当水速较大时,拟髭蟾型的蝌蚪营流水攀吸型生活方式;当水速递减时,掌突蟾型蝌蚪营流水附着型生活方式;当水速进一步递减时,具有较小口漏斗的短腿蟾型蝌蚪和具有大漏斗的角蟾型蝌蚪营流水浮泳型生活。角蟾科蝌蚪对于水流递减的适应演化说明蝌蚪的生态学适应是具有进化意义的;(3)蝌蚪口器内部结构的分化揭示了蝌蚪和食性的适应关系,蝌蚪以口部的唇齿与角质颌刮取或吞吸水中的物质,然后,通过口乳突有选择地过滤进入口腔中食物。拟髭蟾亚科蝌蚪的唇齿多而窄,唇齿间距宽,颌鞘粗而稀,反映了其植食性为主的特点;它们的舌前乳突一般为指状,在口腔入口处所占面积小,其机械过滤的作用很多被唇齿和角质颌分担了;而角蟾亚科的蝌蚪,其角质颌弱,其舌前乳突一般为匙状,几乎填满了口腔入口处,因此舌前乳突起了主要的机械过滤作用。The family Megophryidae is the largest and most diverse families inArchaeobatrachia, and most of its species occur in India, Pakistan, and eastward intoChina, Southeast Asia, Borneo and the Philippines to the Sunda Islands. Currently thefamily includes 142 species have been grouped into two subfamilies, Megophryinaeand Leptobrachiinae. The mountains of central and southern China are rich in speciesof Megophryidae, 75 species belong to 9 genera and two subfamilies.The family was supposed to be ideal materials of studies in many fields of biology,such as taxonomy, evolution, systematics, ecology, and biogeography. Recently, therehave a great development in taxonomy and systematics of megophryids throughstudied by morphology, paleontology, cytology, ecology, and cladistics. However,larvae of megophryids were generally unknown, although the tadpoles might be veryimportant for above studies.In this paper, we examined the evolutionary scenario of the tadpoles’ morphologyin the context of a phylogenetic framework. Our objectives are (1) to evaluate thedivergence of larval body shape and oral discs in the family Megophryidae, (2) toexplore the evolutionary trends of the larvae in megophryidae, and test if thefunnel-shaped oral disc is apomorphic, and (3) to explore the relationship of the larvalstructure, diet and microhabitat.We examined larval morphology of 30 megophryid species, the larval body shape,oral discs, the buccopharyngeal cavity, and jaw sheaths and denticles of the Chinesemegophryid frogs were re-examined. We constructed a phylogeny of the species on thebasis of published mitochondrial cytochrome b and 16S rRNA gene segments usingpartitioned Bayesian analyses. Furthermore, hypothetical changes of larval morphologywere inferred using parsimony principle on the phylogeny. The results showed that:1) Four tadpole types in Megophryidae. The larval morphological charactersseries in Chinese megophryids fall into four general categories according to the bodyshape and oral discs: (A) Leptobrachiini type, species from genera Leptobrachium,Oreolalax, Scutiger and, Vibrissaphora share this type of tadpoles. (B) Leptolalax type,species of genus Leptolalax have this type of tadpoles. (C) Brachytarsophrys type,species of the genus Brachytarsophrys have this type of tadpoles. (D) Megophryinitype, species of the genera Atympanophrys, Ophryophryne, and Xenophrys share this type of tadpoles. Of which B and C are two novel types.2)Taxonomic implications. The present study leads us to reconsider the generalclassification of tribes attributed to members of Megophryidae. More specifically,concerning the phylogenetic relationships and the two novel tadpole types describedherein, we propose a provisional taxonomy for the family but suggest that further taxasampling of other megophryids be performed to confirm this taxonomic change. TheMegophryidae is composed of two subfamilies (Leptobrachiinae and Megophryinae).The Leptobrachiinae was recogonized the two tribes: (1) tribe Leptobrachiini sensuDubois, corresponding to the tadpole of type A, including four genera, i.e.,Leptobrachium, Oreolalax, Scutiger and, Vibrissaphora; (2) tribe Leptolalaxini,corresponding to the tadpole of novel type B, including two genera, i.e., Leptolalaxand Leptobrachella. However, the relationships among the genera of Megophryinaewere largely unresolved, they recognized no monophyletic groups above the generalevel. A more thorough sampling will likely foster a better taxonomic solution.3) The larval evolutionary scenario in Megophryidae.Type A is characteristicof normal-mouthed with multiple tooth rows, representing the tadpole type of theMRCA of Chinese megophryids. Type B is characteristic of normal-mouthed withreduced tooth rows, prolonging labium, and integumetary glands. Type C ischaracteristic of no labial teeth and smaller umbeliform oral disc. Type D ischaracteristic of no labial teeth, enlarged umbeliform oral disc, representing the tadpoleof the MRCA of subfamily Megophryinae. A previous hypothesis, referring tofunnel-shaped oral discs as an apomorphy, is supported.4) The larval adaptation to habitats in Megophryidae. Tadpoles generallyadhere to substrates using their mouths, and the microhabitat that the tadpoles occupyreflects the degree of adhesion and oral complexity. The morphological changes inmegophryid tadpoles virtually allow a progressive adaptation to a changing habitatfrom faster water to slower water. Within the tadpoles of Type A to type D, the TOTbecomes smaller and smaller, and the oral disc orientates from anteroventral toumbelliform upturned, and eye position orientates from dorsal to lateral, and the trunkis more and more depressed and tail becomes relatively longer and slender. Within therunning water, the normal-mouthed with multiple tooth rows of Leptobrachiini tadpoles are correlated with lotic-suctorial, benthic feeders with anteroventral oraldisc and the largest body. With the water’s velocity decreasing, the lotic-adherentfeeders of Leptolalax tadpoles have tube-shaped labium with reduced tooth rows andintegumetary glands. And then, the smaller umbeliform in Brachytarsophrys tadpolesand the enlarged umbeliform oral disc in the Megophryini tadpoles are inhabitmicrohabitats of non-flowing backwaters of rivers, indicative of adaptive traits oflotic-neustonic surface feeders. The scheme of megophryid tadpoles andmicrohabitats provided the first clear evidence which congruent with the hypothesis ofAltig and Johnston (1989). The ecological divergence plays a general role in thedivergence and evolution of megophrid larvae. There is a definite correlation amongthe buccopharyngeal cavity, diet and feeding mechanisms, the tadpole graze orswallow the food particles, then through papillae which like a sieve and sort out foodparticles to the oesophagus. The tadpole of Leptobrachiinae possess multiple toothrows, wide intertooth distance as well as thick and sparse jaw sheath, these tadpolesinhabit bottom of the streams and graze on epiphyton or major detritus of organicmatter on the substrates, their prelingual papillae like single finger, the mechanicalpurpose of papillae served share in by tooth and jaw. The tadpoles of Megophryinaeoccur near the water surface of small streams and are the filter feeder, their dietincludes plankton and organic debris floating on the water surface, those tadpolepossess weak jaw, their prelingual papillae like spoon, the mechanical purpose ofpapillae served mostly for sieve.

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Polyporus moluccensis was newly reported from Hainan Province,Southern China,and its illustrated description was given according to the Chinese specimens.Macroscopically it resembled Polyporus tenuiculus(Beauv.) Fr.,but differed by its smaller basidiospores(5.9~8 × 2.3~3.2 μm vs 8.9~11 × 2.9~4 μm),and by having cystidioles.Polyporus moluccensis grew on rotten angiosperm wood and caused a white rot.

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Traditional agricultural systems are threatened world-wide mainly due to the introduction of modern agricultural techniques and the emigration of farm labourers from remote rural villages. The objective of the programme 'Globally Important Agricultural Heritage Systems' (GIAHS), initiated by the Food and Agriculture Organization (FAO) of the United Nations in 2002, is dynamic conservation of traditional agricultural systems. This article addresses the definition and content of agricultural heritage systems and discusses conservation options in the light of developing rural tourism. An explorative survey was conducted in Longxian village, situated in Zhejiang Province, southern China, focusing on the tourism potential of a typical Rice-Fish Agricultural System. The identification of heritage resources is a first step in the process of transforming an agricultural landscape into a cultural tourism landscape. However, the future of these landscapes is in the hands of a range of stakeholders and depends on their capacity to manage, in a sustainable way, tourism development strategies alongside conservation policies.

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Conductive polyaniline was found to have special marine antifouling property. The coating from conducting polyaniline and epoxy resin(or polyurethane) can last 6-9 months in Southern China sea, i.e., less than 10% of the coating surface was fouled during this period. The conducting polyaniline has special synergetic antifouling effect on other antifouling agents like cuprous oxide or 4, 4'-dichlorodiphenyltrichloroethane. The conductivity of the polyaniline was found to be extremely important for its antifouling effect. Moreover, employing aliphatic polyamine as solvent of emeraldine base and curing agent of epoxy resin, a new technique to process corrosion prevention coating containing emeraldine base was developed, therefrom the emeraldine base and epoxy resin was in molecular level blending. This technique was solvent free and extremely effective, i.e., only 1wt% of emeraldine base in the coating can have good corrosion prevention property.

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Crassostrea ariakensis is an important aquacultured oyster species in Asia, its native region. During the past decade, consideration was given to introducing C. ariakensis into Chesapeake Bay, in the United States, to help revive the declining native oyster industry and bolster the local ecosystem. Little is known about the ecology and biology of this species in Asia due to confusion with nomenclature and difficulty in accurately identifying the species of wild populations in their natural environment. Even less research has been done on the population genetics of native populations of C. ariakensis in Asia. We examined the magnitude and pattern of genetic differentiation among 10 wild populations of C. ariakensis from its confirmed distribution range using eight polymorphic microsatellite markers. Results showed a small but significant global theta (ST) (0.018), indicating genetic heterogeneity among populations. Eight genetically distinct populations were further distinguished based on population pairwise theta (ST) comparisons, including one in Japan, four in China, and three populations along the coast of South Korea. A significant positive association was detected between genetic and geographic distances among populations, suggesting a genetic pattern of isolation by distance. This research represents a novel observation on wild genetic population structuring in a coastal bivalve species along the coast of the northwest Pacific.

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During winter months, a novel overwintering mode of transferring juvenile abalones to open seawaters in southern China rather than keeping them in closed land-based nursery systems in northern China is a popular practice. The initial size, stocking density and sorting are among the first considerations when establishing an abalone culture system. This study aimed to investigate the effects of these factors on the growth of juvenile Pacific abalone, Haliotis discus hannai Ino, during overwintering. Juvenile abalones were reared in multi-tier basket form for overwintering in open seawaters in southern China for 106 days. The daily growth rates (DGRs) in the shell length of all experimental groups ranged from 67.08 to 135.75 mu m day(-1), while the specific growth rates (SGRs) were 0.2447-0.3259% day(-1). Variance analysis indicated that both DGRs and SGRs in shell length were significantly affected by the initial body size and stocking density. Furthermore, the effects of stocking density on DGRs and SGRs varied with the initial size. However, sorting abalones according to their initial sizes may not be necessary in practice as sorting did not alter growth significantly at all densities in this study. Factors potentially affecting abalone growth such as genetic control and intraspecific competition were discussed.

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Prediction of Carbonate Reservoir Based on the Elastic Parameter Analysis Zhang Guangzhi (Solid Geophysics) Directed by Professor Liu Hong Abstract With the exploration and development of Puguang Oilfield, oil-gas exploration of carbonate rock in China has shown good prospects. Research on earthquake prediction methods for carbonate reservoir becomes the key of oil and gas exploration. Starting with analysis of geological characteristics of carbonate rock, prestack AVO inversion method, prestack elastic impedance inversion and parameter calculation method and seismic attribute extraction and optimization method were studied based on the analysis of rock physics in this work. First, variation characteristic and law of carbonate rock reservoir parameters were studied based on experimental data of rock physics, log data, analysis assay data, mud logging data and seismic data, so as to lay a foundation for the further reservoir identification and description. Then, the structure, type and propagation law of seismic wave field were analyzed through seismic forward modeling of the reservoir, and contact between information from log and geology data with elastic parameters, such as compressional wave and shear wave velocity and density were established, so as to provide a standard for reservoir identification and hydrocarbon detection using seismic reflection characteristics of the research area. Starting with the general concept of inverse problem, through analysis of Zoeppritz equation, three kinds of pre-stack inversion methods were derived and analyzed in detail, the AVO 3-parameter inversion based on Bayesian theory, the prestack AVO waveform inversion method and the simultaneous inversion method, based on the statistical hypothesis of inversion parameters and observation data and the Gauss distribution assumption of noise. The three methods were validated by model data and real data. Then, the elastic wave impedance inversion method of carbonate reservoir was investigated and the method of elastic parameter extraction from elastic impedance data was put forward. Based on the analysis of conventional methods of seismic attribute extraction and optimization, the time-frequency attributes and the wavelet attributes with time and amplitude feature were presented, and the prestack seismic attribute calculation method which can characterize the reservoir rock and fluid characteristic was presented. And the optimization of seismic attribute using the nonlinear KPCA method was also put forward. A series of seismic prediction technologies for carbonate reservoir were presented based on analysis of rock physics and seismic forward simulation technology. Practical application of these technologies was implemented in A oil field of Southern China and good effect has been achieved. Key words: carbonate rock; reservoir prediction; rock physics, prestack seismic inversion; seismic attribute

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Superfine mineral materials are mainly resulted from the pulverization of natural mineral resources, and are a type of new materials that can replace traditional materials and enjoy the most extensive application and the highest degree of consumption in the present day market. As a result, superfine mineral materials have a very broad and promising prospect in terms of market potential. Superfine pulverization technology is the only way for the in-depth processing of most of the traditional materials, and is also one of the major means for which mineral materials can realize their application. China is rich in natural resources such as heavy calcite, kaolin, wollastonite, etc., which enjoy a very wide market of application in paper making, rubber, plastics, painting, coating, medicine, environment-friendly recycle paper and fine chemical industries, for example. However, because the processing of these resources is generally at the low level, economic benefit and scale for the processing of these resources have not been realized to their full potential even up to now. Big difference in product indices and superfine processing equipment and technologies between China and advanced western countries still exists. Based on resource assessment and market potential analysis, an in-depth study was carried out in this paper about the superfine pulverization technology and superfine pulverized mineral materials from the point of mineralogical features, determination of processing technologies, analytical methods and applications, by utilizing a variety of modern analytical methods in mineralogy, superfine pulverization technology, macromolecular chemistry, material science and physical chemistry together with computer technology and so on. The focus was placed on the innovative study about the in-depth processing technology and the processing apparatus for kaolin and heavy calcite as well as the application of superfine products. The main contents and the major achievements of this study are listed as follows: 1. Superfine pulverization processing of mineral materials shall be integrated with the study of their crystal structures and chemical composition. And special attention shall be put on the post-processing technologies, rather than on the indices for particle size, of these materials, based on their fields of application. Both technical feasibility and economic feasibility shall be taken into account for the study about superfine pulverization technologies, since these two kinds of feasibilities serve as the premise for the industrialized application of superfine pulverized mineral materials. Based on this principle, preposed chemical treatment method, technology of synchronized superfine pulverization and gradation, processing technology and apparatus of integrated modification and depolymerization were utilized in this study, and narrow distribution in terms of particle size, good dispersibility, good application effects, low consumption as well as high effectiveness of superfine products were achieved in this study. Heavy calcite and kaolin are two kinds of superfine mineral materials that enjoy the highest consumption in the industry. Heavy calcite is mainly applied in paper making, coating and plastics industries, the hard kaolin in northern China is mainly used in macromolecular materials and chemical industries, while the soft kaolin in southern China is mainly used for paper making. On the other hand, superfine pulverized heavy calcite and kaolin can both be used as the functional additives to cement, a kind of material that enjoys the biggest consumption in the world. A variety of analytical methods and instruments such as transmission and scanning electron microscopy, X-ray diffraction analysis, infrared analysis, laser particle size analysis and so on were applied for the elucidation of the properties and the mechanisms for the functions of superfine mineral materials as used in plastics and high-performance cement. Detection of superfine mineral materials is closely related to the post-processing and application of these materials. Traditional detection and analytical methods for superfine mineral materials include optical microscopy, infrared spectral analysis and a series of microbeam techniques such as transmission and scanning electron microscopy, X-ray diffraction analysis, and so on. In addition to these traditional methods, super-weak luminescent photon detection technology of high precision, high sensitivity and high signal to noise ratio was also utilized by the author for the first time in the study of superfine mineral materials, in an attempt to explore a completely new method and means for the study of the characterization of superfine materials. The experimental results are really exciting! The innovation of this study is represented in the following aspects: 1. In this study, preposed chemical treatment method, technology of synchronized superfine pulverization and gradation, processing technology and apparatus of integrated modification and depolymerization were utilized in an innovative way, and narrow distribution in terms of particle size, good dispersibility, good application effects, low consumption as well as high effectiveness of superfine products were achieved in the industrialized production process*. Moreover, a new modification technology and related directions for producing the chemicals were invented, and the modification technology was even awarded a patent. 2. The detection technology of super-weak luminescent photon of high precision, high sensitivity and high signal to noise ratio was utilized for the first time in this study to explore the superfine mineral materials, and the experimental results can be compared with those acquired with scanning electron microscopy and has demonstrated its unique advantages. It can be expected that further study may possibly help to result in a completely new method and means for the characterization of superfine materials. 3. During the heating of kaolinite and its decomposition into pianlinite, the diffraction peaks disappear gradually. First comes the disappearance of the reflection of the basal plane (001), and then comes the slow disappearance of the (hkl) diffraction peaks. And this was first discovered during the experiments by the author, and it has never before reported by other scholars. 4. The first discovery of the functions that superfine mineral materials can be used as dispersants in plastics, and the first discovery of the comprehensive functions that superfine mineral materials can also be used as activators, water-reducing agents and aggregates in high-performance cement were made in this study, together with a detailed discussion. This study was jointly supported by two key grants from Guangdong Province for Scientific and Technological Research in the 10th Five-year Plan Period (1,200,000 yuan for Preparation technology, apparatus and post-processing research by using sub-micron superfine pulverization machinery method, and 300,000 yuan for Method and instruments for biological photon technology in the characterization of nanometer materials), and two grants from Guangdong Province for 100 projects for scientific and technological innovation (700,000 yuan for Pilot experimentation of superfine and modified heavy calcite used in paper-making, rubber and plastics industry, and 400,000 yuan for Study of superfine, modified wollastonite of large length-to-diameter ratio).

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氧化还原敏感元素硒的地球化学循环非常复杂, 它的循环主要受氧化还原势、酸碱度、温度、压力等条件的控制。长期以来,关于硒的主要研究集中在环境生物地球化学领域。对于硒的地质地球化学行为的研究,学者们认为硒不可能独立形成矿床,它主要以伴生元素的形式赋存于一些热液矿床(如,拉尔玛硒-金热液矿床等)。 二十世纪末, 我国学者开始关注硒的矿床地球化学行为, 发现了目前唯一的渔塘坝沉积型的独立硒矿床。另外,下寒武统底部黑色岩系(如,遵义牛蹄塘组)处于地球发展演化的关键时期且富集了众多的有用金属元素, 因此它引起了全世界广大地质学家的普遍关注和重视。这些黑色岩系的共同特点是含有大量的有机质和丰富的金属元素(PGE,Cu,Ni,Mo,Au,U,V,Mn,Fe,Co,Bi,Cr,Se等)。但遵义牛蹄塘组中Ni-Mo多金属层的成因一直争论不休。 本文以拉尔玛硒-金热液矿床、渔塘坝独立硒矿床、遵义黄家湾含Ni-Mo-Se多金属层剖面为研究对象,主要通过硒稳定同位素的测试和不同化学形态的分析结合其他的地球化学参数(如,C-S-Fe体系,氧化还原敏感元素),示踪富硒地层的沉积环境,研究不同地质体系中硒稳定同位素的组成,进而完善硒同位素的理论体系,探讨硒富集过程中的形态迁移途径,并为矿床的形成提供更完善的地球化学证据。通过一系列的研究工作,我们取得了以下几点认识: (1) 通过不同的消解方法准确测定了低硒,高硒样品的总硒含量,相对标准偏差小于10%,而且不同的消解方法测得同样的结果, 满足了地质样品中微量元素的测试要求。由于不同消解方式存在自身的优缺点,我们建议根据不同的样品类型,不同的研究目的选取合适的消解方法。 (2) 通过巯基棉吸附装置达到了纯化富集样品硒的目的, 硒的回收率一般大于90%, 满足同位素测试的需要。应用自制的氢化物发生器与Nu-MC-ICP-MS联用,实现了在线气体进样测试硒稳定同位素的目的。 采用标准样品匹配测试方法校正仪器测试过程中的质量分馏。 硒稳定同位素的测试精度为2δ=0.30‰, 标准NIST SRM 3149采用与样品同样的处理方法,没有发现前处理过程的同位素分馏。 (3) 传统地球化学参数对沉积环境的指示意义。通过氧化还原敏感微量元素及其与TOC的关系和C-S-Fe体系的分析,对渔塘坝独立硒矿床的多元素富集及沉积环境, 遵义黑色岩系沉积环境进行了详细的解释。TS-TFe的关系表明样品中有过量的硫存在,可能为有机硫或为其他亲硫元素提供有利的沉淀条件。C-S-Fe体系及微量元素指数V/(V + Ni) 说明渔塘坝矿区的硅质岩和页岩的沉积环境为缺氧到静海环境, Ni/Co、V/Cr几乎不能作为该区缺氧环境的指示参数, 后者可能由于Cr的外源输入(碎屑、热液等)所致。 C-S-Fe体系及微量元素指数V/(V + Ni)体系指示遵义黑色岩系的沉积环境为微含氧到缺氧的条件, 但对于Ni-Mo矿而言, V/(V + Ni)体系指示其为含氧条件沉积,这可能与Ni-Mo多金属层的成因有关。但铁的硫化度可以指示Ni-Mo多金属层极端的缺氧还原环境。 (4) 硒的形态对古氧化还原条件和矿物质来源的示踪意义。黑色岩系的硒形态分布不同于海洋沉积物,体现了成岩作用对硒形态分布的改变。黑色岩系中硒的主要形态为有机结合态和硫化物/硒化物结合态。硫化物/硒化物结合态比例与铁的硫化程度(DOS)之间明显的相关关系说明在海洋环境中硒主要通过氧化还原反应富集在富有机质的沉积物与沉积岩中。这种相关关系与岩石类型没有关系,这使得将硫化物、硒化物结合的Se(-II)比例作为一个氧化还原条件示踪剂更加可行。DOS与硫化物/硒化物结合态硒的关系,及Se(IV)与Se(-II)的关系均说明遵义牛蹄塘组的K-斑脱岩形成于碱性的氧化环境,Ni-Mo多金属层沉积于微酸性的极端还原环境,而渔塘坝矿床形成于微碱性的还原缺氧环境。生物的同化作用与异化作用之间本身存在互补关系,但这种互补关系却存在不同的转化趋势。不同的转化趋势可能主要受氧化还原反应和酸碱度的控制,其他的地质作用也可能起着重要作用(如,硅酸盐、Fe(II)的含量,硫化物、有机质含量,风化程度等)。同时我们发现相同的氧化还原条件下可能存在不同的富集途径。Ni-Mo多金属层中极少的有机结合态硒暗示海洋同生沉积主要被生物异化还原控制,而沉积物从海洋富集硒的途径主要为直接由Se(VI)和Se(IV)到Se(-II)的还原途径,从高价态到元素态的还原途径可能偶有发生但强度很小。 (5) 硒稳定同位素对矿床成因及物质来源的示踪意义。热液或表生环境中,硒的再次活化迁移对硒同位素的大范围分馏是很重要的。较少的硫化物结合态硒和较大范围的硒同位素组成说明渔塘坝矿床形成时经历了多次氧化还原过程。干酪根硒同位素组成与全岩相似, 而且样品富集轻同位素暗示该矿床硒来的富集主要通过海洋硒的生物吸收同化异化还原与多次无机氧化还原实现。对于拉尔玛金硒矿床而言,未蚀变岩体的硫化物结合态硒富集轻同位素,而后期低温流体的蚀变作用导致蚀变岩体中硫化物结合态硒富集重同位素。干酪根的硒同位素组成暗示热液输入的硒为该矿床硒的主要来源,硒从热液直接进入干酪根的机制是一致的。随着硫含量的增加岩石和矿体中的硒逐渐富集重同位素, 说明海水对矿床富集的贡献是很有限的。遵义黑色岩系中硒同位素组成与Se(-II)之间的关系, 单质硒的缺乏,硒的富集与同位素的关系说明,热液为主要的硒来源,而早寒武世海水中的硒主要通过Se(VI)和Se(IV)到Se(-II)的直接生物还原实现。三个区域的S/Se比值综合说明硫与硒的共同沉降过程中不存在硒的同位素分馏。不同化学形态的分布与不同形态中硒稳定同位素的结合可能会更好的解释硒的全球地球化学循环。 (6) 根据目前硒的同位素分馏体系及所测得的数据,我们初步建立了不同时代、不同成因黑色岩系中硒稳定同位素的分馏模式。