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91.
92.
Injection of carbon dioxide into coal seams is considered to be a potential method for its sequestration away from the atmosphere. However, water present in coals may retard injection: especially if carbon dioxide does not wet the coal as well as water. Thus contact angles in the coal-water-CO2 system were measured using CO2 bubbles in water/coal systems at 40 °C and pressures up to 15 MPa using five bituminous coals. At low pressures, in this CO2/water/coal system, receding contact angles for the coals ranged between 80° to 100°; except for one coal that had both high ash yield and low rank, with a contact angle of 115°, indicating that it was hydrophilic. With increasing pressure, the receding contact angles for the different coals decreased, indicating that they became more CO2-wetting. The relationship between contact angle and pressure was approximately linear. For low ash or high rank coals, at high pressure the contact angle was reduced to 30-50°, indicating the coals became strongly CO2-wetting; that is CO2 fluids will spontaneously penetrate these wet coals. In the case of the coal that was both high ash and hydrophilic, the contact angle did not drop to 90° even at the highest pressures used. These results suggest that CO2 will not be efficiently adsorbed by all wet coals equally well, even at high pressure. It was found that at high pressures (> 2 MPa) the rate of penetration of carbon dioxide into the coals increased rapidly with decreasing contact angle, independently of pressure. Injecting CO2 into wet coals that have both low rank and high ash will not trap CO2 as well as injecting it into high rank or low ash coals. 相似文献
93.
燃煤烟气中SO2治理方法综述 总被引:2,自引:0,他引:2
对燃煤烟气中SO2的脱除方法进行综述和分析。 相似文献
94.
模拟深海热液口环境(最高压力40 MPa,最高温度350℃),对深海热液区的主要成分CO2、CH4及其混合物的水溶液在不同压力和温度条件下的拉曼光谱进行探测和分析,结果显示:常温低压下CO2水溶液的Fermi双峰分别位于1 384.9 cm-1和1 278.3 cm-1处,CH4的水溶液拉曼峰υ1位于2 912.1 cm-1处,均比其气相的拉曼频移小;常温下CO2和CH4水溶液的拉曼特征峰随压力(≤40 MPa)的变化均不明显;在40 MPa的压力下随着温度的升高(≤350℃),CO2水溶液的Fermi双峰分别向高波数区移动了约3.4 cm-1和7.0 cm-1,而CH4水溶液的拉曼峰υ1向低波数区移动了约3.1cm-1;混合后升温过程中CO2的双峰分别向高波数区移动了约4.3 cm-1和3.8 cm-1,CH4的特征峰υ1向低波数区移动了4.5 cm-1。说明在室温到350℃范围内温度的变化对CO2和CH4水溶液拉曼频移有影响,频移量与温度线性相关,而压力在≤40 MPa范围内的改变对拉曼频移影响不明显。 相似文献
95.
营养盐硅和水温影响浮游植物的机制 总被引:1,自引:0,他引:1
通过研究分析Si和水温对浮游植物生长的变化和其集群结构的改变影响,探讨了硅和水温影响浮游植物生长的变化和其集群结构的改变,本文研究发现,浮游植物生长的变化和其集群结构的改变的过程,营养盐硅和水温影响浮游植物生长变化和其集群结构改变的机制,确定了营养盐硅和水温是海洋生态系统的健康运行的动力。 相似文献
96.
不同涂层的二氧化铅电极催化性能的比较 总被引:2,自引:0,他引:2
研究了热分解法和电沉积法制备二氧化铅电极的工艺,通过对苯酚的电解和生成羟基自由基的量,比较了两种方法制得的电极的催化性能,并比较了采用电沉积法制备电极时掺杂铋或镧对电极的催化性能的影响。实验结果表明,这4种电极都具有良好的电催化性能,并且明显降低了槽电压,且对苯酚的降解均符合一级反应动力学,电沉积法制得的电极的催化性能优于热分解法制得的电极,掺镧的电极优于无掺杂和掺铋的电极。 相似文献
97.
Ma Liming 《海洋学报(英文版)》1997,16(2):201-214
On the basis of the data of the partial pressure of CO2 (PCO2)and the concentration of the total dissolved CO2(TCO2) in surface water during the expeditions in Nov.-Dec. 1991, the world ocean circulation experiment (WOCE) and Oct. 1992-Mar. 1993, the tropical ocean-global atmosphere coupled ocean-atmosphere response experiment (TOGA COARE) in the western tropical Pacific and of the comparison with data from 1986 to 1990 TOGA expeditions and that from Japan Meteorological Agency, the response of CO2 in surface water to ENSO event is proved. The CO2 signals indicated that the air-sea system in the western and central tropical Pacific from 1991 to 1993, except for a short period in autumn of 1992, was in a strong state of ENSO.
The change of CO2 in the floating stations near 2°S, 155°E from Nov. 1992 to Mar. 1993 reflected the change of currents, water mass and its thermal and salt content during the forming and developing of ENSO. 相似文献
The change of CO2 in the floating stations near 2°S, 155°E from Nov. 1992 to Mar. 1993 reflected the change of currents, water mass and its thermal and salt content during the forming and developing of ENSO. 相似文献
98.
Shallow-Water Gasohydrothermal Vents of Ushishir Volcano and the Ecosystem of Kraternaya Bight (The Kurile Islands) 总被引:2,自引:0,他引:2
V. G. Tarasov M. V. Propp L. N. Propp A. V. Zhirmunsky B. B. Namsakakv V. M. Gorlenko D. A. Starynin 《Marine Ecology》1990,11(1):1-23
Abstract. A marine ecosystem in the crater of the Ushishir Volcano (Kraternaya Bight, Yankich Island, the Kuriles) showing gasothcrmal activity was studied for hydrographical, hydrochemical, and biological characteristics. Maximal changes in chemical and biological characteristics were observed in the surface water layer of 0–5 m. This layer had higher water temperature, was saturated with volcanogcnic carbon dioxide (up to 2000 10-6 torr), ovcrsaturatcd with oxygen (up to 200 %), and contained high concentrations of chlorophyll a. Hydrogen sulfide was found in the surface water layer and at a depth of 15 m in the area of maximal effect of volcanic effluents.
The planktonic community is characterized by high rates of production and destruction of organic matter only in the 0–5 m layer. Daily vertical migrations of the ciliatc Mesodinium rubrum were observed, which caused "red tides".
Bacterial, algobacterial, and diatom mats developed on the bottom of the bight in the zone of gasohydrothermal vents and in areas of volcanic water seeping. The rate of organic matter production in algobacterial mats reached 33.4g C-rrr2 -d-l , chcmolithotrophy predominating. Bottom settlements had high population density and great animal biomass, which reached 10 kg m-2 in gasohydrothermal fields. They obtain sufficient energy from primary production of microphy-tobenthos, algobacterial, and bacterial mats. Bcnthic species dominant in the bight were not found off the Ushishir Islands.
Some species of macrobenthos inhabiting the Kraternaya Bight differ markedly in size and biomass from the same species found beyond the bight. 相似文献
The planktonic community is characterized by high rates of production and destruction of organic matter only in the 0–5 m layer. Daily vertical migrations of the ciliatc Mesodinium rubrum were observed, which caused "red tides".
Bacterial, algobacterial, and diatom mats developed on the bottom of the bight in the zone of gasohydrothermal vents and in areas of volcanic water seeping. The rate of organic matter production in algobacterial mats reached 33.4g C-rrr
Some species of macrobenthos inhabiting the Kraternaya Bight differ markedly in size and biomass from the same species found beyond the bight. 相似文献
99.
以钛酸四丁酯(TEOS)、去离子水为原料,离子液体1-丁基-3-甲基四氟硼酸咪唑盐([Bmim]BF4)为表面活性剂,通过溶剂热法制备了锐钛矿相TiO2纳米颗粒。用X-射线衍射仪(XRD)、扫描电镜(SEM)、紫外-可见吸收光谱仪(UV-Vis)对产物的晶相、形貌和光学性能进行表征。为了评估光催化活性,并以甲基橙水溶液为研究对象,在紫外光照射下分析不同照射时间下光降解效率。结果表明,离子液体、去离子水和钛酸四丁酯的体积比为1.3∶1∶1.3时,反应所得到的TiO2具有较高光催化活性,明显优于未添加离子液体的产品,这一结果可归因于其具有较大的比表面积。 相似文献
100.
P. A. Polito Y. Bone J. D. A. Clarke T. P. Mernagh 《Australian Journal of Earth Sciences》2013,60(6):833-855
The Junction gold deposit, in Western Australia, is an orogenic gold deposit hosted by a differentiated, iron‐rich, tholeiitic dolerite sill. Petrographic, microthermometric and laser Raman microprobe analyses of fluid inclusions from the Junction deposit indicate that three different vein systems formed at three distinct periods of geological time, and host four fluid‐inclusion populations with a wide range of compositions in the H2O–CO2–CH4–NaCl ± CaCl2 system. Pre‐shearing, pre‐gold, molybdenite‐bearing quartz veins host fluid inclusions that are characterised by relatively consistent phase ratios comprising H2O–CO2–CH4 ± halite. Microthermometry suggests that these veins precipitated when a highly saline, >340°C fluid mixed with a less saline ≥150°C fluid. The syn‐gold mineralisation event is hosted within the Junction shear zone and is associated with extensive quartz‐calcite ± albite ± chlorite ± pyrrhotite veining. Fluid‐inclusion analyses indicate that gold deposition occurred during the unmixing of a 400°C, moderately saline, H2O–CO2 ± CH4 fluid at pressures between 70 MPa and 440 MPa. Post‐gold quartz‐calcite‐biotite‐pyrrhotite veins occupy normal fault sets that slightly offset the Junction shear zone. Fluid inclusions in these veins are predominantly vapour rich, with CO2?CH4. Homogenisation temperatures indicate that the post‐gold quartz veins precipitated from a 310 ± 30°C fluid. Finally, late secondary fluid inclusions show that a <200°C, highly saline, H2O–CaCl2–NaCl–bearing fluid percolated along microfractures late in the deposit's history, but did not form any notable vein type. Raman spectroscopy supports the microthermometric data and reveals that CH4–bearing fluid inclusions occur in syn‐gold quartz grains found almost exclusively at the vein margin, whereas CO2–bearing fluid inclusions occur in quartz grains that are found toward the centre of the veins. The zonation of CO2:CH4 ratios, with respect to the location of fluid inclusions within the syn‐gold quartz veins, suggest that the CH4 did not travel as part of the auriferous fluid. Fluid unmixing and post‐entrapment alteration of the syn‐gold fluid inclusions are known to have occurred, but cannot adequately account for the relatively ordered zonation of CO2:CH4 ratios. Instead, the late introduction of a CH4–rich fluid into the Junction shear zone appears more likely. Alternatively, the process of CO2 reduction to CH4 is a viable and plausible explanation that fits the available data. The CH4–bearing fluid inclusions occur almost exclusively at the margin of the syn‐gold quartz veins within the zone of high‐grade gold mineralisation because this is where all the criteria needed to reduce CO2 to CH4 were satisfied in the Junction deposit. 相似文献