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81.
生烃化学动力学在川东北普光气田的应用   总被引:9,自引:2,他引:7  
普光气田是四川盆地近期发现的规模最大、埋藏最深、资源丰度最高的气田。通过认识普光气田各个烃源岩层的贡献量、生烃关键期与构造演化的关系、油气成藏具体模式等,建立生烃化学动力学模型、标定参数,结合地区烃源岩参数和地史、热史资料,定量描述该地区的生烃过程及油裂解成气过程。认为:普光地区的主力烃源岩为下志留统泥岩;主要干酪根生油期为早二叠世末到早三叠世末期(距今286Ma至240Ma);主要干酪根生气期为中三叠世(距今240Ma至230Ma);主要气源是原油后期热裂解气,原油裂解成气的时间比较晚,主要油裂解成气期为早白垩世(距今144Ma至97.5Ma),从而决定了普光气田的成藏模式为“多期成藏,油气转化,晚期定位”。图2表3参33  相似文献   
82.
The objective of this study is to determine the chemical kinetics of desulphurization of Thai limestone in an atmospheric fluidized bed combustor (AFBC). The experiments, which employed the batch technique using the limestone samples from six major sources in Thailand, were performed in a laboratory‐scale AFBC. The results obtained were analysed and correlated in the form of apparent reaction rate and deactivation rate constants as a function of operating conditions of the furnace and their properties, respectively. The formulae derived from these correlations were kept as general as possible in order that they could be used as input parameters for the selected mathematical model of desulphurization in an AFBC that is suitable for practical use. The predicted results were in good agreement with the experimental data reported in the literature. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
83.
In this study, a single unit of planar micro-solid-oxide fuel cell (μSOFC) is investigated numerically to evaluate the influences of flow channel design, oxygen composition, and thermal operating conditions on cell performance. Four flow channel designs are examined under the co-flow configuration: serpentine, double serpentine, rod bundle, and oblique rib. For all designs, the contacts areas of interconnect to electrodes are kept consistent to maintain the ohmic losses at the same level. To characterize the mass transport effects, there are three different compositions, 100% O2, 50% O2/50% N2 and air, fed to the cathode inlet. Different thermal conditions, adiabatic and isothermal, are applied to the outer boundary of the μSOFC and the results are compared. The outcomes suggest that both thermal conditions and oxidant composition show remarkable influences on μSOFC performance. Under adiabatic conditions, the rise of cell temperature causes a decrease in reversible voltage, deteriorating the overall cell competence. When oxygen is diluted with nitrogen, local gas diffusion becomes dominant to the cathode reaction. Bulk flow, on the other hand, plays a minor role in cell performance since there is little deviation in the polarization curves for all flow channel designs, even at high current densities. For comparison, the flow visualization technique is employed to observe the transport phenomena in various flow channel designs. The flow patterns are found to resemble the concentration distribution, providing a useful tool to design μSOFCs.  相似文献   
84.
The effect of hydrogen heat treatment on impurity contents in aluminum nitride powder of different fineness is studied. Thermodynamic calculations are provided pointing to the possibility of forming gaseous hydrogen compounds with impurity elements. It is established that as a result of treatment the contents of impurity elements, i.e. oxygen, carbon, sulfur, are reduced by a factor of 3-13. The optimum hydrogen heat treatment regime is determined: a temperature of 1323 K and an exposure time of 30 min.  相似文献   
85.
张昕 《石油机械》1998,26(4):14-15,22
为提高抽油机减速器齿轮铸件的机械性能,提出以Sn代替Mo作为合金元素,并通过试验确定了合理的Si、Cu、Sn的加入量。指出Si加入量应控制在1.9%-2.1%范围内,同时加入0.36%~0.9%的Cu和0.025%~0.07%的Sn,可保证球铁的强度和延伸率都满足QT700-2的要求。鉴于试件与实际铸件的表面硬度有一定的差值,为提高铸件表面硬度,进行了余热正火试验,并给出了铸件在铸型内的时间-冷却温度曲线。最后根据球铁化学成分的选择结果,进行了齿轮生产试验。  相似文献   
86.
An improved set of parameters for vanadium in the semiempirical quantum chemical SCF MO method SINDO1 is presented. It is shown that both the geometries and heats of formation of a number of vanadium-containing compounds calculated by this method are in good agreement with available experimental data. Model clusters of increasing size are used for the study of geometric and energetic properties of vanadium pentoxide. Both hydrogen atom and proton adsorption on the (010) surface of vanadium pentoxide and a subsequent formation of different oxygen vacancies have been investigated. Based on these computational results the reactivities of V2O5-surface oxygen atoms for adsorption are discussed.  相似文献   
87.
S Gopalakrishna  Y Jaluria 《Sadhana》1994,19(5):817-832
A numerical study of the transport phenomena arising in a single-screw extruder channel is carried out. A non-Newtonian fluid is considered, using a power law model for the variable viscosity. Chemical reaction kinetics are also included. Finite difference computations are carried out to solve the governing set of partial differential equations for the velocity, temperature and species concentration fields, over a wide range of governing parameters for the case of a tapered screw channel. The numerical treatment for this combined heat and mass transfer problem is outlined. A marching procedure in the down-channel direction is adopted and the validity of the scheme for practical problems discussed. For large viscous dissipation, the material heats up considerably due to the prevailing shear field, affecting the viscosity significantly, and results in large changes in the pressure development at the end of the channel. The rate of reaction controls the mass diffusion rate which in turn affects viscosity and the flow significantly. The dimensionless throughput,q v , is one of the most important parameters in the numerical solution. The dimensionless pressure variation is very sensitive toq v , and orders of magnitude changes are possible for small variations inq v . Schemes for dealing with other important effects such as back flow, heat transfer by conduction in the barrel, and the effect of the die are also outlined. A list of symbols is given at the end of the paper This is publication No. F-10544-4-91 of the New Jersey Agricultural Experiment Station supported by State Funds and the Center for Advanced Food Technology (CAFT). The Center for Advanced Food Technology is a New Jersey Commission on Science and Technology Center. This work was also supported in part by the US Army Research Office.  相似文献   
88.
总结回顾了1994年中国化学工业的改革及发展现状,提出了1995年化工生产建设的目标及在化工行业改革方面的四项试点工作,强调了编制“九五”计划的重要性。  相似文献   
89.
Surface free energies of polyurethanes made from toluene diisocyanate and 1, 4 butanediol-based hard segments and caprolactone polyol-based soft segments were calculated using additive functions. Good agreement was found between the calculated values based on additive functions and the calculated values based on contact angle measurements. The phase-separated polyurethanes were found to have a higher polar surface free energy component (γP). This was linked to the preferential segregation of butanediol/butanediol-derived moieties to the polyurethane surfaces due to phase separation. The adhesion values of these polyurethanes to soda-lime glass were correlated with their respective γP values and a linear relationship was found. It was also shown that the adhesion values of the low γP polyurethanes improved substantially when the glass surfaces were coated with a thin layer of butanediol prior to the bonding. The modulus of the interphase region rich in butanediol was evaluated. Although a modulus increase was found at the interface, this increase was found to play a secondary role in the adhesion. The chemical interactions at the polyurethane/glass interphase were investigated by pre-treating the glass surfaces with methyl-trimethoxysilane and trimethylchlorosilane prior to adhesion testing. The adhesion data showed no significant difference between the uncoated and the silane-treated glass substrates. Based on this experimental evidence, the possibility of any covalent or ionic bonding at the polyurethane/glass interphase was assumed negligible. It was determined that the mechanism of adhesion between the polyurethanes and the glass surface could be through the formation of an interphase region in which hydrogen bonding between the butanediol-rich interphase region and the hydroxylated glass surface plays a key role.  相似文献   
90.
CH_4、CO_2与O_2制合成气的研究 Ⅱ工艺条件的影响   总被引:1,自引:0,他引:1  
在固定床反应器中考察了12%Ni-5%RE-2%Cu-2%Li/Al2O3(mass)催化剂在CH4、CO2与O2催化氧化重整制合成气反应中催化剂粒径、工艺操作条件(空速与温度)及原料气配比对反应的影响,确定了较佳的操作条件:催化剂粒径20~40目,反应最佳温度为800℃,SV=4×104ml/(g·h)。同时看到在不同的原料气配比的条件下该催化剂的活性亦很稳定,不仅达到了反应平衡,且产物V(CO)/V(H2)比有很强的调变性。  相似文献   
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