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41.
油煤浆的管道输送特性与管路设计原则 总被引:2,自引:0,他引:2
宋新南 《石油学报(石油加工)》2003,19(2):94-100
通过理论分析和管道实验,探讨了油煤浆在工业管道输送中的流变特性、流动状态和阻力特性,得出了油煤浆的物性参数、表观参数、管道阻力参数的测定值和计算公式,并在此基础上探讨了油煤浆管道输送的设计原则,为油煤浆管路的设计提供基础数据、计算方法和一般原则。 相似文献
42.
张岚 《有色冶金设计与研究》2007,28(4):105-107
企业对盈亏临界点的计算通常是以变动成本法为基础,但也有以制造成本法为计算基础的,对于这两种成本方法计算的几种盈亏临界点的情况,本文结合案例,通过比较分析认为:盈亏临界点的计算应当以变动成本法为基础更为合理。 相似文献
43.
Five flow improvers have been synthesized to study rheological properties of Nada crude oil (Gujarat, India). Anhydride copolymers were prepared making use of the copolymerization of acrylates of different alkyls with maleic anhydride and the Poly (n-alkyl acrylates-co-N-hexadecylmaleimide) were prepared by the reaction of copolymer with hexadecylamine. The additives were purified and characterized by FTIR, GPC. The prepared polymeric additives shows dual function both as wax dispersants and flow improvers and all of them acts as good pour point depressants. Yield stress and the viscosity of the crude oil at different temperatures and concentrations of additives were evaluated by zero friction advanced rheometer AR-500 of TA instrument. Comparison of morphologies and structures of wax crystals or aggregates in waxy crude oils beneficiated with and without a PPD was also done by micro photographic studies which show the modification in wax crystal morphology due to additives. 相似文献
44.
A generalized kinematic viscosity-temperature correlation for undefined liquid heavy petroleum fractions has been developed to represent the data for a wide range of temperature from 100°C to 200°C. The correlation is based on the experimental kinematic viscosity data of true boiling point fractions of four Arabian crude oils. The characterization property required for estimation is 50% boiling point. The proposed correlation fits the experimental data with an overall absolute error of 6.1%. Experimental measurements of kinematic viscosity of heavy true boiling point fractions of Arabian crude oils were also obtained in order to develop the proposed correlation. 相似文献
45.
This paper deals with the issues of development and implementation of a real-time NURBS interpolator for a six-axis robot. Using an open-architecture controller system as a testbed, a real-time NURBS curve interpolator was developed, implemented and tested. Sample runs were conducted with the resulting trajectories measured in real-time during robot motion. The resulting trajectories are analyzed, discussed and compared with those from a commonly used point-to-point approximation technique. The real-time NURBS curve interpolator's feasibility, advantages and related issues are also discussed. 相似文献
46.
布尔函数的对偶性和线性点 总被引:5,自引:1,他引:4
本文主要讨论了部分自对偶和部分反自对偶函数、部分线性函数以及具有线性点的函数的性质。 相似文献
47.
In this paper we present an efficient technique for piecewise cubic Bézier approximation of digitized curve. An adaptive breakpoint detection method divides a digital curve into a number of segments and each segment is approximated by a cubic Bézier curve so that the approximation error is minimized. Initial approximated Bézier control points for each of the segments are obtained by interpolation technique i.e. by the reverse recursion of De Castaljau's algorithm. Two methods, two-dimensional logarithmic search algorithm (TDLSA) and an evolutionary search algorithm (ESA), are introduced to find the best-fit Bézier control points from the approximate interpolated control points. ESA based refinement is proved to be better experimentally. Experimental results show that Bézier approximation of a digitized curve is much more accurate and uses less number of points compared to other approximation techniques. 相似文献
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