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排序方式: 共有477条查询结果,搜索用时 757 毫秒
1.
加氢渣油催化裂化七集总动力学模型的建立 总被引:1,自引:0,他引:1
以加工加氢渣油的茂名石化3^#重油催化裂化装置的工业数据为基础,针对加氢渣油的特点,提出了以渣油四组分作为划分原料集总基础的催化裂化七集总动力学模型。通过变尺度法(B-F-G-S)和龙格库塔法确定动力学参数,并通过工业实测数据验证,表明该模型具有良好的拟合性和外推性,较好地反映了加氢渣油催化裂化反应规律。 相似文献
2.
A remarkable nonlinearity has been observed for electric transport in K-TCNQ (potassium tetracyanoquinodimethane) quasi-one-dimensional
conductor. The negative differential resistance region appears afterV
m (turn over voltage), beyond which voltage goes down with increase of current. A possible mechanism is discussed in terms
of dynamics of charged solitons and domain walls in one-dimensional molecular stacks of these types of crystals. 相似文献
3.
4.
本文介绍了特大型油罐整体一次性控制爆破拆除方案及其实施方法,这一方法与水压爆破拆除和常规钻孔爆破拆除方法相比,具有工效高,安全性好的突出优点。 相似文献
5.
Model test of the cutting properties of a shearer drum 总被引:1,自引:1,他引:0
According to similarity theory, we carded out a dimensional analysis of the shearer drum correlation parameters and built similarity criteria. Based on these, similarity models of shearer drums were developed. Simultaneously, based on an estab-lished cutting testbed of the coal and rock, cutting tests of different pick arrangements of the drum models were carried out, where the compressive strength of the analogous cutting material was 2.48 MPa and the drum rotary speed 67.5 r/min. The variance, the mean values, maxima and mean maxima of the torque load were analyzed for different type drum models. Moreover, the relation-ships between the type of pick arrangements and the cutting lump coal percentage were studied. The results indicate that the load fluctuation of the sequence drum is larger than that of the punnett square drum in the cutting process and the lump coal percentage and economic benefits of the sequence drum are inferior to the punnett square drum. We conclude that the punnett square drum is superior to the sequence drum. 相似文献
6.
In this paper we propose a compact split step Padé scheme (CSSPS) to solve the scalar higher-order nonlinear Schrödinger equation (HNLS) with higher-order linear and nonlinear effects such as the third and fourth order dispersion effects, Kerr dispersion, stimulated Raman scattering and power law nonlinearity. The stability of this method has been proved. It has been shown as well that the CSSPS method gives the same results as classical numerical methods like the split step Fourier method and Crank–Nicholson (CN) method but it presents many advantages over theme. It is more efficient. This proposed scheme is well suited to higher-order dispersion effects and readily generalized for nonlinear and dispersion managed fibers. We tested this scheme for the case of the quintic nonlinearity and confirmed that this effect has no significant role on the propagation of single solitons. 相似文献
7.
《国际计算机数学杂志》2012,89(5):864-882
Systems of coupled non-linear Schrödinger equations with soliton solutions are integrated using the six-point scheme which is equivalent to the multi-symplectic Preissman scheme. The numerical dispersion relations are studied for the linearized equation. Numerical results for elastic and inelastic soliton collisions are presented. Numerical experiments confirm the excellent conservation of energy, momentum and norm in long-term computations and their relations to the qualitative behaviour of the soliton solutions. 相似文献
8.
研究同时具有二阶和三阶非线性效应的一维浅栅光子晶体中的矢量耦合模孤子动力学。从Maxwell方程出发,利用多重尺度法,导出了电光场、光学整流场与基频光场包络的非线性矢量耦合模方程组,给出了耦合模方程组的孤子解。结果表明由二阶非线性导致的光学整流场对基频光场没有调制作用。 相似文献
9.
余热锅炉是一种非标设计、非标制作的锅炉,它运行的好坏与其所配置的冶金炉烟气性质有着非常密切的关系。本介绍了我厂24m^2锌焙烧沸腾炉余热锅炉在结构及配置等方面进行改进前后的不同状况。 相似文献
10.
介绍15206综放面在回采过程中,采取了放震动炮、改进机组滚筒截齿、合理调整割煤速度、改变放项煤工艺等技术措施,增加了块炭率,提高了煤炭质量,取得了可观的经济效益。 相似文献