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81.
82.
将汉白玉废料通过高温煅烧分解得到氧化钙,再用氯化铵循环液溶解氧化钙制得碱性氯化钙溶液,除去其中的Mg、Fe等杂质得到氯化钙精制溶液,利用化学方法合成得到碳酸钙粉体.用X射线衍射(XRD)、扫描电镜(SEM)及激光粒度分析仪、白度仪对碳酸钙产品的晶相组成、形貌、粒度分布、白度及化学组成进行了分析,所得产品为纯度达98.5%以上、白度达97%以上、平均粒度为80nm左右的球形纳米级碳酸钙.并对碳化反应速率及合成球形纳米碳酸钙的影响因素进行了分析.实验中循环使用NH4Cl,氨的排放量小,减少了环境污染. 相似文献
83.
P. Farzadi 《Journal of Petroleum Geology》2006,29(2):159-173
Interpretation of recently acquired 3D seismic data from the adjacent Sirri C and D oilfields in the SE Persian Gulf indicates that a 3D interpretation of seismic facies is crucial to resolve the internal stratal geometries of the Aptian Dariyan Formation. This carbonate formation passes southward into the Shu'aiba Formation, a prolific reservoir rock of similar facies in the UAE. Lack of exposures and limited cored intervals have forced reliance on the seismic data for evidence of the depositional environment and the internal architecture of potential reservoir rocks. The progradational nature of the Dariyan Formation and the occurrence of carbonate build‐ups within it make this stratal geometry complex. The complex internal heterogeneity of the build‐ups and presence of seismic noise make mapping of the build‐ups in 3D space using conventional seismic interpretation tools difficult, despite the availability of high‐quality 3D seismic data covering the area. The high quality seismic and limited well data from this field is one of the few datasets of this kind presented in the literature. A procedure for the hierarchical multi‐attribute analysis of seismic facies using Paradigm's Seis Facies software is used in this study to provide a 3D interpretation of the stratal patterns. Principal component analysis reduces the noise and redundant data by representing the main data variances as a few vector components in a transformed coordinate system. Cluster analysis is performed using those components which have the greatest contribution to the maximum spread of the data variability. Six seismic attribute volumes are used in this study and the result is a single 3D classified volume. Important new information obtained from within the Dariyan Formation gives new insights into its stratigraphic distribution and internal variability. This method of processing seismic data is a step towards exploring for subtle stratigraphic traps in the study area, and may help to identify exploration targets. 相似文献
84.
硅酸盐矿物和碳酸盐矿物是构成地壳的主要造岩矿物,论述了两类矿物溶解动力学的研究现状与展望,指出两类矿物的溶解和沉积过程中CO2吸收和释放,对全球环境有重要影响。 相似文献
85.
Fatigue behaviour and endurance limit of graphite and of aluminium‐infiltrated graphite Fatigue properties of polycrystalline, isotropic graphite FU2590 and of FU2590 infiltrated with AlSi7Mg (FU2590/AlSi7Mg) were investigated in reversed bending tests at 25 Hz at numbers of cycles below 107 and in tension‐compression tests at 20 kHz below 109 cycles. The open porosity of Graphite (10‐11 Vol.‐%) was infiltrated with the aluminium alloy using the squeeze casting infiltration method, which led to an increase of the bending strength by 50 %, increase of tensile strength by 30 % and increase of stiffness by 15 %. Fully reversed tension‐compression loading of FU2590 delivers a mean endurance limit at 109 cycles at the normalized maximum stresses (i.e. maximum tension stress of a cycle divided by the static strength) of 0,65±0,03. Mean numbers of cycles to failure of 104 were found in fully reversed bending tests at the normalized maximum stress of 0,78. The infiltrated material shows approximately 30 % higher cyclic strength in reversed bending tests, and the mean endurance limit under tension compression loading increases by 15 %. The increased endurance limit of the infiltrated material is caused by the increased stiffness. The increased toughness of graphite due to the infiltration with aluminium is of additional beneficial influence at the higher cyclic stresses investigated in reversed bending tests and in static tests. 相似文献
86.
87.
用屏蔽暂堵技术封堵水平井裂缝性漏层 总被引:1,自引:1,他引:0
克拉玛依油田HW702水平井的大斜度段和水平段,将穿越纵向裂缝发育的二叠系佳木河组储层。为安全钻进和保护油层,用超细碳酸钙和磺化沥青复配后加入复合离子钻井液中成屏蔽暂堵的堵漏钻井液。室内用岩心试验,屏蔽暂堵后渗透率可降为0,暂堵深度小于3cm,可用酸化和射孔解堵。现场使用效果也很好,使HW702水平井顺利完钻,并获得工业油气流。 相似文献
88.
P Pramanik 《Bulletin of Materials Science》1995,18(6):819-829
Ultrafine (⩽ 150 nm) powders of spinels [MFe2O4 where M = Ni(II), Co(II) and Zn(II)]; rare-earth orthoferrites [RFeO3 where R = Sm, Nd and Gd], and rare-earth garnets [R3Fe3O12 where R = Sm, Nd and Gd] with good purity and chemical homogeneity were prepared through two new versatile chemical routes.
The first route involved the coprecipitation of the desired metal nitrates from their aqueous solution, in presence of a water
soluble polymer-polyvinyl alcohol (PVA), by triethyl ammonium carbonate solution. The other process involved complete evaporation
of a mixture of optimum amounts of PVA and the desired aqueous metal nitrate solutions, with and without the addition of optimum
amounts of urea when the mixture was evaporated to a pasty mass. In addition, detailed study on the reported potassium ferricyanide
route was also carried out for the production of the rare-earth orthoferrite powders. The various precursor as well as the
heat-treated mixed-oxide powders, prepared through each of the routes, were compared by the physical characterization studies
involving thermal gravimetry and differential scanning calorimetry, infrared spectroscopy, X-ray powder diffraction, transmission
electron microscopy, and room temperature magnetic measurements. 相似文献
89.
指出了压力铸造及热挤压工艺生产铝合金减震筒的缺点,阐述了液态挤压的特征,介绍了液态挤压在减震筒上的应用,分析了比压值对制件性能的影响。 相似文献
90.