二氧化碳溶解气对原油粘度的影响

利用高温高压油气水混合液粘度测量装置对原油及含二氧化碳气原油的粘温特性进行了实验研究,测量了不同气油比条件下油气混合液的粘度,分析了二氧化碳溶解气对原油粘度的影响。结果表明,在相同压力下,原油及其混合液粘度与温度存在指数关系,原油粘度与压力基本呈线性关系。在同一温度下,油气混合液的粘度在达到泡点压力之前随着压力的升高而降低;在达到泡点压力之后,随压力的升高而增大;油气混合液的粘度随气油比增加而减小;油气混合液的泡点压力随着含气量的增加和温度的升高而增大。     

等焓节流的快速迭代法

本文介绍了等焓节流过程的数学模型.推导出在解等焓节流问题时求泡点温度和露点温度的简便公式,大大加速了对等焓节流过程的计算.     

二氧化碳溶解气对原油粘度的影响

利用高温高压油-气-水混合液粘度测量装置对原油及含二氧化碳气原油的粘-温特性进行了实验研究，测量了不同气油比条件下油-气混合液的粘度，分析了二氧化碳溶解气对原油粘度的影响。结果表明，在相同压力下，原油及其混合液粘度与温度存在指数关系，原油粘度与压力基本呈线性关系。在同-温度下，油-气混合液的粘度在达到泡点压力之前随着压力的升高而降低；在达到泡点压力之后，随压力的升高而增大；油-气混合液的粘度随气油比增加而减小；油-气混合液的泡点压力随着含气量的增加和温度的升高而增大。     

常见热力学模型对馏分油加压汽液平衡计算的适用性：孤岛,…

依据孤岛，中原，克拉玛依原油馏分油压力下２２８个窄馏分汽液相平衡常数，回归屈Ｋ值关联式，该式对泡点温度预测的绝对平均偏差为４．７℃，根据实测数据，对常用热力学模型进行了适用性考察。     

非共沸制冷剂在工业制冷中的应用分析

非共沸制冷剂在相变过程中存在温度滑移,能够缩小相变过程的传热温差,进而减小换热器的传热不可逆损失,有利于提高制冷循环的效率,非常适合于变温热源的应用。所以非共沸制冷剂在变工况的工业制冷中有较大的应用前景。对于非共沸制冷剂,换热器选型时应注意温度滑移造成的影响,否则可能无法保证正常的换热器余量。对于冷凝器应选择泡点作为计算冷凝温度;蒸发器选型应使用露点温度。     

提高非理想溶液精馏过程计算机模拟速度

比较了用于非理想溶液的3种泡点计算方法,提出了精馏计算中改进的xij的调整方法,比较了2种xij的调整方法与3种泡点计算方法的各种组合对计算时间的影响.     

提高非理想溶液精馏过程计算机模拟速度

比较了用于非理想溶液的 3种泡点计算方法 ,提出了精馏计算中改进的 xij的调整方法 ,比较了 2种 xij的调整方法与 3种泡点计算方法的各种组合对计算时间的影响。     

神经网络技术用于醇水盐体系汽液平衡关联和预测

运用神经网络,对32个醇水盐体系的汽液平衡数据进行了关联,计算值与实验值符合良好,泡点温度和汽相组成的平均偏差分别是0.93 K和0.015.对未列入该模型的体系的汽液平衡进行了预测,也取得了较好的结果.     

油气藏流体—CO2体系相行为的实验测定与计算

利用高压相平衡实验装置,地某油田Ｆ６６Ａ井和Ｆ３０井的原油在油藏温度下注入不同量的ＣＯ２（注入ＣＯ２与油藏流体的摩尔比为０￣２．００）时的ＰＶＴ关系进行了测定,共取得ＰＶＴ数据点１６５个,泡点压力点和体积系数点各１１个。实验结果表明帛于原始油样的组分结构和组成不同,其注气体系相行为有较大的不同。Ｆ６６Ａ井油藏原油的饱和（泡点）压力随着ＣＯ２注入量的增加近似呈线性增加,而Ｆ３０井的饱和压力和ＣＯ注入     

辽河原油常压汽液平衡CORGC状态方程的预测

应用ＣＯＲＧＣ状态方程，根据正构烷烃模型分子法确定石油假组分的基团组成，仅需平衡沸点一个物性参数，即可按假多元系法预测汽液相平衡常数和体系的泡点、露点温度。结果表明，预测精度与ＡＰＩ推荐的ＳＰＫ状态方程相当。     

利用LiDAR数据提取山谷(脊)线的关键技术研究

在分析利用LiDAR数据提取山谷(脊)线关键步骤的基础上,针对传统三维流水模拟方法采用单一汇水量阈值提取山谷(脊)线所存在的无法提取既完整又可靠的山谷(脊)线的局限,提出了动态设定汇水量阈值的模型。在实验中,采用正交测试法对动态阈值模型的参数取值进行测试,得到了较合理参数值,实验结果表明,采用动态阈值能够提取更准确的山谷(脊)线。     

基于局部直方图均衡化的指纹方向图算法

针对低质量指纹图像的纹理信息和灰度梯度信息遭到严重破坏的问题,提出一种基于局部直方图均衡化的指纹方向图算法.此算法结合指纹谷点与其相邻脊点特有的灰度差规律,修改了经典直方图均衡化的累积分布函数,用于放大源图像的纹理信息,使图像趋于二值化.基于放大的纹理信息,采用改进的点方向图算法计算指纹的谷点方向,使用直方图块方向图法赋予脊点方向,同时校正谷点的点方向,得到完整的方向图.通过对FVC2006指纹库中的部分低质量图像的增强结果进行比较,此算法对低质量指纹图像的增强性能优于传统算法.     

Constrained circulation at Endeavour ridge facilitates colonization by vent larvae

Understanding how larvae from extant hydrothermal vent fields colonize neighbouring regions of the mid-ocean ridge system remains a major challenge in oceanic research. Among the factors considered important in the recruitment of deep-sea larvae are metabolic lifespan, the connectivity of the seafloor topography, and the characteristics of the currents. Here we use current velocity measurements from Endeavour ridge to examine the role of topographically constrained circulation on larval transport along-ridge. We show that the dominant tidal and wind-generated currents in the region are strongly attenuated within the rift valley that splits the ridge crest, and that hydrothermal plumes rising from vent fields in the valley drive a steady near-bottom inflow within the valley. Extrapolation of these findings suggests that the suppression of oscillatory currents within rift valleys of mid-ocean ridges shields larvae from cross-axis dispersal into the inhospitable deep ocean. This effect, augmented by plume-driven circulation within rift valleys having active hydrothermal venting, helps retain larvae near their source. Larvae are then exported preferentially down-ridge during regional flow events that intermittently over-ride the currents within the valley.     

Geophysical evidence for reduced melt production on the Arctic ultraslow Gakkel mid-ocean ridge

Most models of melt generation beneath mid-ocean ridges predict significant reduction of melt production at ultraslow spreading rates (full spreading rates &<20 mm x yr(-1)) and consequently they predict thinned oceanic crust. The 1,800-km-long Arctic Gakkel mid-ocean ridge is an ideal location to test such models, as it is by far the slowest portion of the global mid-ocean-ridge spreading system, with a full spreading rate ranging from 6 to 13 mm x yr(-1) (refs 4, 5). Furthermore, in contrast to some other ridge systems, the spreading direction on the Gakkel ridge is not oblique and the rift valley is not offset by major transform faults. Here we present seismic evidence for the presence of exceptionally thin crust along the Gakkel ridge rift valley with crustal thicknesses varying between 1.9 and 3.3 km (compared to the more usual value of 7 km found on medium- to fast-spreading mid-ocean ridges). Almost 8,300 km of closely spaced aeromagnetic profiles across the rift valley show the presence of discrete volcanic centres along the ridge, which we interpret as evidence for strongly focused, three-dimensional magma supply. The traces of these eruptive centres can be followed to crustal ages of approximately 25 Myr off-axis, implying that these magma production and transport systems have been stable over this timescale.     

Evidence of recent volcanic activity on the ultraslow-spreading Gakkel ridge

Seafloor spreading is accommodated by volcanic and tectonic processes along the global mid-ocean ridge system. As spreading rate decreases the influence of volcanism also decreases, and it is unknown whether significant volcanism occurs at all at ultraslow spreading rates (<1.5 cm yr(-1)). Here we present three-dimensional sonar maps of the Gakkel ridge, Earth's slowest-spreading mid-ocean ridge, located in the Arctic basin under the Arctic Ocean ice canopy. We acquired this data using hull-mounted sonars attached to a nuclear-powered submarine, the USS Hawkbill. Sidescan data for the ultraslow-spreading (approximately 1.0 cm yr(-1)) eastern Gakkel ridge depict two young volcanoes covering approximately 720 km2 of an otherwise heavily sedimented axial valley. The western volcano coincides with the average location of epicentres for more than 250 teleseismic events detected in 1999, suggesting that an axial eruption was imaged shortly after its occurrence. These findings demonstrate that eruptions along the ultraslow-spreading Gakkel ridge are focused at discrete locations and appear to be more voluminous and occur more frequently than was previously thought.     

论太行山地貌系统

论述了太行山地貌系统的发育背景,地貌特点,形成条件和特征。提出太行山地貌是一种阶梯状地貌。一个完整的太行山地貌系统,在地层上,应包含华北地台基底和中元古界—寒武系—奥陶系盖层。在地貌形态上,发育众多的峡谷群;通常在峡谷下部,常为深切的河谷,或嶂谷;在中部,峡谷较为宽阔,两侧地形缓坡之上为陡峭的山坡,高耸的崖壁,即断崖、长崖;顶部,常见平缓的台地或平台以及长脊、长墙。     

Isotopic evidence for Late Cretaceous plume-ridge interaction at the Hawaiian hotspot

When a mantle plume interacts with a mid-ocean ridge, both are noticeably affected. The mid-ocean ridge can display anomalously shallow bathymetry, excess volcanism, thickened crust, asymmetric sea-floor spreading and a plume component in the composition of the ridge basalts. The hotspot-related volcanism can be drawn closer to the ridge, and its geochemical composition can also be affected. Here we present Sr-Nd-Pb isotopic analyses of samples from the next-to-oldest seamount in the Hawaiian hotspot track, the Detroit seamount at 51 degrees N, which show that, 81 Myr ago, the Hawaiian hotspot produced volcanism with an isotopic signature indistinguishable from mid-ocean ridge basalt. This composition is unprecedented in the known volcanism from the Hawaiian hotspot, but is consistent with the interpretation from plate reconstructions that the hotspot was located close to a mid-ocean ridge about 80 Myr ago. As the rising mantle plume encountered the hot, low-viscosity asthenosphere and hot, thin lithosphere near the spreading centre, it appears to have entrained enough of the isotopically depleted upper mantle to overwhelm the chemical characteristics of the plume itself. The Hawaiian hotspot thus joins the growing list of hotspots that have interacted with a rift early in their history.     

曲面拟合方法从DEM中提取线性信息

依据Haralick提出的使用最小二乘法拟合曲面提取线性信息的原理,研究了具体实现方法,并依此编制了提取线性信息的程序。应用该程序从实验数据中提取了山脊线与山谷线,并对应其联贯性不好的缺点提出了相应的改进方案。     

Hydrological response to a seafloor spreading episode on the Juan de Fuca ridge

Seafloor hydrothermal systems are known to respond to seismic and magmatic activity along mid-ocean ridges, often resulting in locally positive changes in hydrothermal discharge rate, temperature and microbial activity, and shifts in composition occurring at the time of earthquake swarms and axial crustal dike injections. Corresponding regional effects have also been observed. Here we present observations of a hydrological response to seafloor spreading activity, which resulted in a negative formation-fluid pressure transient during and after an earthquake swarm in the sediment-sealed igneous crust of the Middle Valley rift of the northernmost Juan de Fuca ridge. The observations were made with a borehole seal and hydrologic observatory originally established in 1991 to study the steady-state pressure and temperature conditions in this hydrothermally active area. The magnitude of the co-seismic response is consistent with the elastic strain that would be expected from the associated earthquakes, but the prolonged negative pressure transient after the swarm is surprising and suggests net co-seismic dilatation of the upper, permeable igneous crust. The rift valley was visited four weeks after the onset of the seismic activity, but no signature of increased hydrothermal activity was detected in the water column. It appears that water, not magma, filled the void left by this spreading episode.     

Discovery of abundant hydrothermal venting on the ultraslow-spreading Gakkel ridge in the Arctic Ocean

Submarine hydrothermal venting along mid-ocean ridges is an important contributor to ridge thermal structure, and the global distribution of such vents has implications for heat and mass fluxes from the Earth's crust and mantle and for the biogeography of vent-endemic organisms. Previous studies have predicted that the incidence of hydrothermal venting would be extremely low on ultraslow-spreading ridges (ridges with full spreading rates <2 cm x yr(-1)-which make up 25 per cent of the global ridge length), and that such vent systems would be hosted in ultramafic in addition to volcanic rocks. Here we present evidence for active hydrothermal venting on the Gakkel ridge, which is the slowest spreading (0.6-1.3 cm x yr(-1)) and least explored mid-ocean ridge. On the basis of water column profiles of light scattering, temperature and manganese concentration along 1,100 km of the rift valley, we identify hydrothermal plumes dispersing from at least nine to twelve discrete vent sites. Our discovery of such abundant venting, and its apparent localization near volcanic centres, requires a reassessment of the geologic conditions that control hydrothermal circulation on ultraslow-spreading ridges.