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超高压输电线路智能巡检机器人是输电工程技术发展的重要内容.介绍了一种应用于500 kV 超高压输电线路带电巡检智能巡检机器人系统.重点介绍了该巡检机器人系统的视觉监视与检测方法及应用技术.此类机器人系统可在输电线路上实现监控状态下的自主行走与视觉监视,跨越杆塔等作业,可在野外环境下完成连续巡检作业.这种作业方式,将大大减轻输电维护人员的劳动强度与难度,提高巡检效率与质量.对输电工程的安全可靠运行具有重要意义.

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The Sanmen Gorge area is located in the southernmost margin of the Chinese Loess Plateau with well developed eolian deposit sequence for the past 2.6 Ma, providing a key site for further understanding of the evolution history of the East Asian monsoon since late Pliocene. This study attempted to characterize the stratigraphy and paleoclimate record of the loess-paleosol sequence in the Songjiadian section. The work involved includes systematic field investigation, paleomagnetic and rock magnetic analyses, grain size and major chemical composition analyses, and multiple proxy measurements of magnetic susceptibility, color reflectance and the ratio of CBD-dissolvable iron to the total iron (FeD/FeT). By comparisons of the Songjiadian section with well studied loess sections in the west of the Sanmen Gorge, the spatial variations of the East Asian monsoon was evaluated for some periods during which typical loess or paleosols developed. The following conclusions have been obtained. 1. Stratigraphic correlation and paleomagnetic result demonstrate that the loess-paleosol sequence in the Songjiadian section was accumulated from 2.6Ma, and is generally a complete and continuous loess sequence. However, notable differences from type loess sections have been identified for a few loess and paleosol units, featured by absence or anomalous thickness in the Songjiadian section. 2. Magnetic susceptibility and chromaticity records clearly reveal the loess-paleosol cycles, and indicate that the Sanmen Gorge area has been warmer and more humid than the Lingtai and Jingchuan sections in the western central Loess Plateau since the Early Pleistocene. 3. Grain size distribution patterns are typical of eolian dust, and show a great similarity between various units of loess and paleosols, and between the S32 and the underlying Red Clay through the Songjiadian profile, suggesting the eolian origin for the loess, paleosols and the Red Clay. 4. Comparison of the FeD/FeT curves from different loess sections indicates a stronger chemical weathering in the Songjiadian section and notable enhancement around 1800, 800 and 600 ka BP, implying the strengthening of the East Asian monsoon during these periods. In contrast, it was weakened at 1100 ka BP. Generally, the summer monsoon shows a gradually decreasing trend during the entire Pleostocene, but the spatial pattern typified by an increasing trend in weathering intensity from north to south remained the same. 5. The loess unit L9 in the Songjiadian section displays two geomagnetic field anomalies with the midpoint ages of 0.917 and 0.875 Ma respectively, with a segment of 12 ka. They are demonstrated to be equivalent to the Santa Rosa and Kamikatsura geomagnetic excursions. 6. Magnetite is the main magnetic carrier for both loess and paleosols. Maghemite concentration is higher in paleosols than in loess, and is an important carrier for the enhanced magnetic susceptibility in paleosols. Magnetic fabric analysis suggests a dominant N-S wind direction prevailing in the L9 and L15, while the summer winds were dominantly in NNE-SSW direction during the S8 period, notably differing from previous studies.

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对末次间冰期以来洛川黄土进行了有机磷/无机磷(Porg/Pinorg)比值测量。结果表明,黄土中Porg/Pinorg比值的分布主要受降水量和温度的影响,是有机磷和无机磷在不同时期随气候变化相互转化的结果。此指标的变化与黄土—古土壤的变化大致相关,与洛川黄土磁化率曲线相一致,与深海氧同位素可进行很好的对比。此比值与夏季风强弱程度乃至与全球气候变化有密切的联系。Porg/Pinorg比值可作为一种反映古气候环境变迁的新指标。

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甘肃文县阳山金矿的探明黄金储量已达308t,平均品位4.74g/t,是我国地质勘查储量最大的金矿床。该矿床产于西秦岭造山带,是一个同碰撞形成的类卡林型金矿床,矿体受EW向韧脆性剪切带控制,赋矿围岩为泥盆系碳质千枚岩-板岩-碳酸盐-硅质岩和侵入其中的花岗斑岩脉。流体成矿过程包括:形成石英-绢云母-黄铁矿组合的早阶段,形成石英-黄铁矿-毒砂-方铅矿等多金属组合的主成矿阶段,形成碳酸盐-辉锑矿-石英网脉的晚阶段。 与矿体关系较为密切的花岗斑岩富集LILE 和 LREE, 亏损 Ba, Sr, Nb, Ta, P 和Ti,ΣREE=54.35~124.01 μg/g ,(La/Yb)N=9.72~27.80,δEu=0.70~0.89, ISr值为0.70806~0.71756,平均0.71107;εNd(t)平均-3.4;Nd模式年龄(T2DM)平均1.34(Ga)。表明花岗斑岩岩浆应源自成熟度较低的中元古代基底地壳物质。花岗斑岩的(206Pb/204Pb)220Ma、(207Pb/204Pb)220Ma和(208Pb/204Pb)220Ma的平均值分别为17.875、15.604和38.296,与秦岭微陆块的中元古代基底和碧口地体碧口群的Pb同位素组成一致。考虑到前人获得碧口群的年龄为1.235~1.367Ga,而秦岭微陆块沿勉略缝合带向南仰冲到碧口地体之上,我们认为由碧口群等组成的俯冲板片的变质脱水熔融作用导致了阳山金矿带花岗斑岩的形成。因此,阳山金矿带的花岗斑岩是扬子与华北大陆中生代碰撞造山过程中形成的同碰撞花岗岩类。 最新的S,Sr和Pb同位素研究表明:热液成矿早阶段的黄铁矿的34S值范围介于-15.5‰~6.59‰之间,总体离散性比较大,显示沉积地层来源的特征,硫同位素组成属离散型,不具有岩浆主导的成矿的塔式效应。花岗岩中黄铁矿硫同位素范围很集中,34S值处于-1.47‰~2.12‰之间,本区花岗斑岩不可能为成矿物质的主要来源。矿石硫化物的初始锶同位素比值范围较大(0.70877~0.71697,平均为0.71258),显示成矿物质并非单一来源,考虑到花岗斑岩先于矿床形成,只在后期构造作用的岩体部分成矿的地质事实,少量矿石中的低锶同位素比值黄铁矿有可能来自作为围岩的花岗斑岩,也可能来自基底物质。矿石硫化物Pb同位素206Pb/204Pb=17.552~18.853,平均18.260;207Pb/204Pb=15.574~15.928,平均15.685;208Pb/204Pb=37.894~39.293,平均38.680,变化范围比较大。μ=9.46~10.06,平均为9.65,ω值介于36.96~42.21,显示了铅源的物质成熟度较高,要求最佳物源是浅变质化学-碎屑沉积建造,恰好与本区泥盆构造层为浅变质细碎屑岩夹薄层灰岩系的特征一致,部分低Sr和Pb同位素比值的成矿物质可能来自于作为围岩的花岗斑岩和/或者基地物质。 总结前人阳山金矿床的H-O-C同位素体系的研究得出,初始成矿流体来源于碳酸盐地层或相似岩石建造的变质或/和改造脱水,成矿流体系统从早到晚、从深到浅,由变质热液演变为大气降水热液。与本文得出的结论一致。 总而言之, 阳山金矿矿成矿流体的来源早期具有变质水特征,应来自赋矿地层或相似岩性组合的改造或变质脱水作用,晚阶段大气水为主的流体性质。成矿物质主要来自于赋矿围岩。流体经过作为部分围岩的花岗斑岩时从中萃取少部分成矿物质,而导致了少部分的低锶、铅同位素的矿石硫化物组成。 在中生代扬子板块北缘(包括碧口地块)向南秦岭陆陆碰撞过程中,扬子北缘板片沿勉略断裂向北俯冲到南秦岭之下,下插板片增温增压,发生变质、脱水和部分熔融。碰撞中期,构造背景由挤压向伸展转变,减压增温的环境导致大量变质流体沿深大断裂向上运移,不断萃取围岩中大量成矿元素,并将成矿元素搬运至有利于流体聚集、成矿物质卸载的空间,使成矿物质富集成矿。阳山金矿床定位于泥盆系构造层中,成矿时代为190Ma左右,紧随花岗斑岩侵入作用(220Ma左右),主成矿作用发生于碰撞作用由挤压-伸展转变期的减压增温环境。成岩、成矿模式与CMF模式吻合。 阳山超大型金矿是世界罕见的碰撞造山带内类卡林型金矿床,其地质地球化学特征复杂、独特,流体性质主要与造山型金矿一致,矿床地质主要与卡林型金矿一致,部分特征兼与造山型和卡林型两类矿床之间,花岗斑岩本身成矿的特点又为阳山所特有,总体具有造山型向卡林型金矿过渡的性质。因此建议以“秦岭式”或“阳山式”类卡林型金矿床代表与阳山金矿具有类似成矿背景及地球化学性质的矿床。

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A perovskite-type oxide of Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCFO) with mixed electronic and oxygen ionic conductivity at high temperatures was used as an oxygen-permeable membrane. A tubular membrane of BSCFO made by extrusion method has been used in the membrane reactor to exclusively transport oxygen for the partial oxidation of ethane (POE) to syngas with catalyst of LiLaNiO/gamma-Al2O3 at temperatures of 800-900 degreesC. After only 30 min POE reaction in the membrane reactor, the oxygen permeation flux reached at 8.2 ml cm(-2) min(-1). After that, the oxygen permeation flux increased slowly and it took 12 h to reach at 11.0 ml cm(-2) min(-1). SEM and EDS analysis showed that Sr and Ba segregations occurred on the used membrane surface exposed to air while Co slightly enriched on the membrane surface exposed to ethane. The oxygen permeation flux increased with increasing of concentration of C2H6, which was attributed to increasing of the driving force resulting from the more reducing conditions produced with an increase of concentration of C2H6 in the feed gas. The tubular membrane reactor was successfully operated for POE reaction at 875 degreesC for more than 100 h without failure, with ethane conversion of similar to 100%, CO selectivity of >91% and oxygen permeation fluxes of 10-11 ml cm(-2) min(-1). (C) 2002 Elsevier Science B.V. All rights reserved.

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Novel mixed conducting oxides, B-site Bi-doped perovskites were exploited and synthesized. Cubic perovskite structures were formed for BaBi0.2COyFe0.8-yO3-delta (y less than or equal to 0.4) and BaBixCo0.2Fe0.8-xP3-delta (x=0.1-0.5) The materials exhibited considerable high oxygen permeability at high temperature. The oxygen permeation flux of BaBi0.2Co0.35Fe0.45O3-delta membrane reached about 0.77 x 10(-6) mol/cm(2) s under an air/helium oxygen partial pressure gradient at 900 degrees C, which was much higher than that of other bismuth-contained mixed conducting membranes. The permeation fluxes of the materials increased with the increase of cobalt content, but no apparent simple relationship was found with the bismuth content. The materials also demonstrated excellent reversibility of oxygen adsorption and desorption. Stable time-related oxygen permeation fluxes were found for BaBi0.2CO0.35Fe0.45O3-delta and BaBi0.3Co0.2Fe0.5O3-delta a membranes at 875 degrees C.

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A mixed-conducting perovskite-type Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCFO) ceramic membrane reactor with high oxygen permeability was applied for the activation of methane. The membrane reactor has intrinsic catalytic activities for methane conversion to ethane and ethylene. C-2 selectivity up to 40-70% was achieved, albeit that conversion rate were low, typically 0.5-3.5% at 800-900 degreesC with a 50% helium diluted methane inlet stream at a flow rate of 34 ml/min. Large amount of unreacted molecular oxygen was detected in the eluted gas and the oxygen permeation flux improved only slightly compared with that under non-reactive air/He experiments. The partial oxidation of methane to syngas in a BSCFO membrane reactor was also performed by packing LiLaNiO/gamma -Al2O3 with 10% Ni loading as the catalyst. At the initial stage, oxygen permeation flux, methane conversion and CO selectivity were closely related with the state of the catalyst. Less than 21 h was needed for the oxygen permeation flux to reach its steady state. 98.5% CH4 conversion, 93.0% CO selectivity and 10.45 ml/cm(2) min oxygen permeation flux were achieved under steady state at 850 degreesC. Methane conversion and oxygen permeation flux increased with increasing temperature, No fracture of the membrane reactor was observed during syngas production. However, H-2-TPR investigation demonstrated that the BSCFO was unstable under reducing atmosphere, yet the material was found to have excellent phase reversibility. A membrane reactor made from BSCFO was successfully operated for the POM reaction at 875 degreesC for more than 500h without failure, with a stable oxygen permeation flux of about 11.5 ml/cm(2) min. (C) 2001 Elsevier Science B.V. All rights reserved.