117 resultados para 453


Relevância:

10.00% 10.00%

Publicador:

Resumo:

自治式无缆水下机器人能很好地抑制各自由度运动的耦合效应和等效于各自由度的力扰动,有效地克服附连水惯量的不利影响,充分改善系统的动态性能。笔者提出了自治式无缆水下机器人加速度控制.通过合理的加速度计布置方案抵消载体转动及柯氏力的影响,利用垂直陀螺精确补偿重力影响.进而构成相应的加速度及速度控制回路.仿真结果表明,引入加速度反馈大大改善了其速度回路的动态响应,增强了系统的鲁棒性.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The reservoir of Zhongerbei region in Gudao Oilfield is a typical fluvial facies deposit, its serious heterogeneity of the reservoir caused the distribution of remaining oil in mature reservoirs is characterized by highly scattered in the whole field, and result to declination of production, tap potential and stabilize production is more difficult. Reservoir modeling based on lay scale can not fulfill requirement. How to further studied reservoir heterogeneity within the unit and establish the finer reservoir modeling is a valid approach to oil developing. The architectural structure elements analysis is the effectively method to study reservoir heterogeneity. Utilize this method, divide the reservoirs of Gudao Oilfield into ten hierarchies. The priority studying is sixth, seven hierarchies, ie single sand layers sand bodies By the identification of sixth, seven hierarchies, subdivide the reservoir to the single genetic unit. And to subdivide by many correlation means, such as isometry and phase transition, accomplish closure and correlation of 453 wells.Connectting fluvial deposit pattern, deposition characteristic with its log, build the inverting relation between “sedimentary facies” and “electrofacies” The process emphasize genetic communication and collocation structure of genetic body in space. By detailed architecture analyses sandbodies’ structure, this paper recognize seven structure elements, such as major channel, abandoned channel, natural levee, valley flat, crevasse splay, crevasse channel and floodplain fine grain.Combination identification of architectural structure elements with facieology and study of deposition characteristic, can further knowing genesis and development of abandoned channel. It boost the accuracy to separation in blanket channel bodies distribution, and provide reference to retrieving single channel boundary. Finally, establish fine plane and section construction. On basis architectural structure map, barrier beds and interbeds isopach map and mini-structure map, considering single thin layers to be construction unit, the main layer planimetric maps have drawn and the inner oil-water boundary have revealed. All account that architectural structure elements control remaining oil distribution in layer, and develop the study on architectural structure elements to direct horizontal well is succesful.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Hersai porphyry copper deposit(PCD) of eastern junggar, newly discovered copper deposit, is located at the eastern segment of the Xiemisitai-Kulankazigan-Zhifang-Qiongheba Paleozoic island arc, Eastern Junggar. The Hersai PCD is developed in a intrusive complex, characterized by intensive and multiform hydrothermal alteration, including potassic alteration, silification, chloritization,sericitization,kaolinitization and carbonatization. Granodiorite, grandiorite porphyry, granite and concealed explosion breccia are hosts of the ore bodies containing veinlet and disseminated ore. Ore-bearing granite (ZK107-1-9), granodiorite (ZK107-1-9) and Ore-barren granodiorite (HES2-1) are selected to date zircon U-Pb age by SHRIMP method, and have an age of 429.4±6.4Ma ,413.0±3.4Ma and 411.1±4.8Ma, respectively, showing that they were emplaced from Late Silurian to Early Devonian. In addition, sample ZK107-1-9 has some hydrothermal zircons with a weighted mean 206Pb/238U age of 404.9±3.7Ma which is interpreted to be related to the granodiorite porphyry. Re-Os dating of five molybdenite samples yielded a weighted average model age of 408.0±2.9Ma, indicating the metallogenic epoch of the Hersai PCD. The ore-forming age is close to the petrogenic time of garnodiorite (411-413Ma), this suggests the ore-forming porphyry is most possiblely granodiorite porphyry. Systematic major - trace elements and Rb-Sr-Sm-Nd-Pb-Hf isotopic characteristics were studied. Analysis results show that these intrusives have some interesting and special characteristics, as following:1) containing both calc-alkaline rocks and high potassium calc-alkaline rocks ; 2) have some characteristics of adakite, but not totally, such as much lower La/Yb ratios and no Eu anomaly or just faint Eu anomaly; 3) have an initial 87Sr/86Sr ratios(0.703852-0.704565) similar to that of BSE, positive εNd(t) values between 6.1 and 7.4, the initial 206Pb/204Pb values (17.576-17.912), 207Pb/204Pb values (15.400-15.453) , 208Pb/204Pb values (37.252-37.466) , and high εHf(t) values (10.2-15.4) close to the value of depleted mantle. These geochemical features suggest that these igneous rocks in the Hersai area not only have some characteristics of island arc, but also some characteristics that only appear in the continental margin arc. It is suggested that Hersai PCD is formed in the subduction setting by the partial melting of young crust. These works and advancements mentioned in the paper are helpful to understand the deposit geology, geochemistry and metallogenesis of Hersai PCD. It is also significant to understand mineralization and tectonic setting in the Qiongheba area.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

于2004年7月对太湖北部浮游藻类的种群组成进行了调查,分析了藻类利属组成的空间分布,利用多种多样性评价指数对水体的污染情况进行了评价,初步探讨了太湖藻类种群组成的变化特征。太湖北部浮游藻类的密度较大,介于2.54×10^7~8.53×10^8个·L^-1,主要由蓝藻、绿藻、硅藻、甲藻、裸藻和隐藻等组成,以微囊藻为优势种。自湖岸向湖心,单位体积内藻类的个数及生物量逐渐递减,种属逐渐增加。其中含较多指示污染及富营养化程度的藻类种属,各种评价指数显示水体的污染程度较为严重,属中营养一富营养化范畴.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

以云蒙山变质核杂岩东侧的河防口低角度正断层为研究对象,通过矿物(黑云母)的变形特征和形成环境分析,获得了该断层带上的构造热演化环境:温度为780~860℃,压力约为7.3×10^8-8.6×10^8pa。提出云蒙山变质核杂岩的成因机制是,在区域伸展背景下,处于半固结状态的云蒙山花岗岩在东南侧卷入河防口-水峪伸展型韧性剪切带,使花岗岩发生中高温条件的韧性变形;之后,该韧性剪切带在隆升过程中不断向浅层次过渡,形成了一些浅层次的脆性伸展变形构造。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

分析了四川冕宁大型稀土矿床硫同位素组成。结果显示成矿期脉石矿物重晶石与矿化期后硫化物(黄铁矿和方铅矿)的硫同位素组成明显不同,前者富集^34S,其δ^34S为+1.8‰~+6.7‰,后者富集轮S,其δ^34S在-10.9‰~-2.1‰之间,表明本区成矿流体中的硫和矿化期后富含硫化物流体中的硫具有不同的来源。矿区各种类型矿石中的重晶石均普遍遭受过风化作用,且δ^34S随风化作用的增强而增加,暗示物理分馏效应是本区重晶石硫同位素组成差异的主要原因,重晶石风化过程实际上是一个贫弛^32、富^34S过程,未风化重晶石的δ34S与典型幔源硫的^δ34S(0‰左右)相近,成矿流体中硫主要来源于地幔。矿石中重晶石风化作用过程中被淋滤的^32S可能是矿化期后富含硫化物流体中的硫的重要来源,但有待深入研究.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

老厂矿床位于三江成矿带南段昌宁—孟连裂谷的次级澜沧断陷盆地中,昌宁—孟连裂谷是三江成矿带南段的重要成矿段之一,其大地构造位于保山―掸邦微陆块东缘,兰坪—思茅盆地、临沧地块西缘,属东特提斯构造域,是冈瓦纳古陆与欧亚大陆巨型缝合带的组成部分。 矿床开采历史悠久,始于明朝永乐二年(1404年),至今已605年。古时炼银弃铅,最高年产白银30万两。解放后主要开采古人废弃的高铅炉渣,并对深部原生矿体进行了初步勘探,90年代至今对深部银铅矿体进行了详细勘查,深部矿体是矿床主要的开采对象。它以独特的成矿地质特征、富银(铅锌矿石中平均含量为629×10-6,方铅矿中平均2069×10-6)、伴生元素多(In、Se、Te、Ga、Cd、Bi)、规模大(In、Se、Te、Cd已达大型规模)、含Sn等特征而受到广大地质工作者的关注。它是“三江”成矿带南段最具代表性的铅银矿床类型之一,也是昌宁—孟连裂谷内目前探明的唯一大型银铅锌多金属矿床,具有十分重要的研究价值。 虽然前人已从矿床地质、成矿条件、控矿因素等方面对老厂大型银铅锌多金属矿床进行过研究,但研究工作较为零散,在成矿物质与成矿流体来源、矿床成因、花岗斑岩与成矿等方面还存在较大争议。本文在深入细致的野外地质工作基础上,利用多种现代分析测试技术,对矿床进行了较为系统的矿物学、岩石学、年代学和矿床地球化学研究,进而查明了矿床成矿物质与成矿流体来源、揭示了成矿地球动力学背景、探讨了矿床的成因、初步建立了矿床成因模式。论文取得的主要成果如下: 1.查明了硫化物的物质组分及形成阶段。闪锌矿以高铁(早期平均11.51%,晚期平均8.41%)为基本特征,并伴生多种特征的微量元素,早期闪锌矿是Fe、In的主要载体,Cu、Cd、Mn则主要富集在晚阶段闪锌矿中;方铅矿是Ag的主要载体,其早期富Ag、Te、Bi,含Se、Cu,中期主要富Ag,晚期以含As、Bi为特征;其它硫化物成分较单一。 2.揭示了伴生元素赋存状态和富集规律。矿床伴生元素含量高,闪锌矿中Cd平均4293.19×10-6,In平均555.37×10-6,方铅矿中Te平均143.81×10-6,As、Se、Bi、Ga含量也很高。初步估算金属储(万吨)量分别为: Ga 0.097,Cd1.84, In0.13,Se0.06 ,Te0.15,Bi1.28,As4.31。闪锌矿是Ga、In、Cd主要载体,Te、Bi主要赋存在方铅矿中,Se则主要在铅锌、黄铁矿石中富集。 3.首次获得了精确的成矿年代学数据。单颗粒闪锌矿—黄铁矿Rb-Sr法获得矿床成矿年龄t=(45±3.6)Ma,(87Sr/86Sr)i=0.70977±0.00034。证实了矿床成矿与隐伏花岗斑岩关系密切,矿床形成是三江成矿带南段对喜马拉雅碰撞造山成矿运动的响应。 4.首次系统研究了花岗斑岩的地质、地球化学特征。矿床花岗斑岩具高硅、超钾、富碱、贫钠和低镁、钙、铁、磷的特征,岩石为过铝质岩石;其轻稀土富集、Eu为弱负异常、基本无Ce异常、岩石富集大离子亲石元素,具有较高的锶初始值和较低εNd及高的Nd模式年龄,与三江地区富碱斑岩具有相似的地球化学特征。岩浆主要来源于加厚下地壳重熔,成岩过程中有地幔物质的加入,为同碰撞构造环境下形成。 5.首次探讨了容矿沉积建造及矿石、矿物的地球化学特征。矿床碳酸盐岩轻稀土富集、Eu正异常及Ce异常和其微量元素特征与热水沉积岩石相似,表明了碳酸盐岩的热水沉积成因,同时矿石及其硫化物微量和稀土元素特征也指示了在早石炭世矿区发生了广泛的火山喷流热水沉积成矿作用。 6.查明了成矿物质及成矿流体来源。成矿元素研究显示矿床成矿物质具有多来源的特征,Pb同位素研究表明矿床Pb可能来自不同地层岩石的淋滤, S同位素组成显示其可能主要来源于海水对下伏火山岩地层的淋滤与海水硫酸盐的还原,花岗斑岩岩浆也可能提供了部分S。C-O、H-O同位素和矿石及其硫化物稀土元素反映矿床早期成矿流体主要源于深部岩浆,晚期主要来源于喜山期花岗斑岩岩浆热液。 7.初步建立了成矿模式。老厂矿床是长期以来多种地质作用下的综合产物,具有成矿物质多来源,成矿阶段多期次特点。经历了早石炭世火山喷流热水沉积成矿和喜山期花岗斑岩岩浆热液叠加改造成矿作用,热水成矿作用下形成了以黄铁矿为主的块状硫化物矿床,喜山期富碱花岗斑岩岩浆热液流体携带了大量的Cu、Mo、Ag、Pb等成矿元素,在它的叠加改造作用下形成了老厂银多金属矿床。总之矿床为火山喷流沉积—岩浆热液叠加改造成因。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Orthogonal design and uniform design were used for the optimization of separation of enantiomers using 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CD) as a chiral selector by capillary zone electrophoresis, The concentration of DM-beta-CD, buffer pH, running voltage, and capillary temperature were selected as variable parameters, their different effects on peak resolution were studied by the design methods. It was concluded that orthogonal design offers a rapid and efficient means for testing the importance of individual parameters and for determining the optimum operating conditions. However, for a large number of both factors and levels, uniform design is more efficient, The effect of addition of methanol and citric acid buffer on the separation of enantiomers was also examined.