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21.
热带城市垃圾典型组分的热解特性研究   总被引:7,自引:0,他引:7  
卢苇  马晓茜 《太阳能学报》2002,23(3):357-360
对热带城市垃圾的几种典型组分进行了热解实验,得到了它们的失重曲线,通过对失重曲线进行分析,得到了这几种典型组分的热解规律,并通过建立热解动力学模型,求出了其中两种组分的活化能E和频率因子A。  相似文献   
22.
A new technique, namely, the open-die backward extrusion test technique, was developed as an alternative method to the ring compression test in order to quantitatively evaluate the coefficient of friction, μ, at the die/workpiece interface. This technique relates the percentage deformation in height of the specimen to the percentage increase in extruded height of the specimen. In this study, the open-die backward extrusion tests (ODBET) were simulated for different aspect ratios, (H/D), and different die geometries, (d/D), by utilizing an elastic-plastic finite element code (ANSYS) in order to obtain the friction calibration curves (FCCs). The results indicated that the extruded height is related to the friction conditions at the die/workpiece interface. Therefore, ODBET can be used to generate FCCs to determine the coefficient of friction at the die/workpiece interface in large deformation processes.  相似文献   
23.
A model has been developed to study the effects of chemical kinetics on the residue curve maps (RCM) for reactive distillation systems with liquid phase splitting. In the model, chemical reaction can occur in both or only one of the two liquid phases. The heating policy V/V0=H/H0 is applied so that the kinetic effect can be described by a single parameter, the Damköhler number Da. The effects of reaction kinetics on pseudohomogeneous and heterogeneous mixtures have been compared. The properties of their RCMs are the same outside, but are fully different inside the liquid-liquid (L-L) region if they have different chemical equilibrium curves. Inside the L-L region, the chemical equilibrium curve coincides to a unique reactive liquid-liquid tie line in case that the pseudohomogeneous chemical equilibrium curve intersects with the L-L envelope. When the reaction occurs in only one of the two liquid phases, the residue curves inside the L-L region are strongly affected by the L-L envelope, especially at high Da. In the present paper, first an illustrative arbitrary reaction system, and then the reaction of cyclohexene with water to cyclohexanol are analysed with respect to their RCMs.  相似文献   
24.
Tuning the performance parameters of all stations of interlinked manufacturing and assembly systems to ensure the planned capacity is a major challenge. The application of system simulation for this task is little common, particularly in SMEs. A suitable tool for quickly assessing the specific influence of a standalone station on the entire system performance has been developed on the basis of the characteristic curve theory. The applied methodology and the results obtained are presented in this paper.  相似文献   
25.
This work introduces a new imaging technique, Rotated Image with Maximum Average Power Spectrum (RIMAPS), for use in determining orientation and characteristics of surface topography. It consists of computing the maximum value of the averaged power spectrum, given by one step of the two‐dimensional Fourier transform, for each angle of rotation of a digitized image. The basic measurement science of this technique is described and different cases are studied. The characterization of simple geometrical figures explains the meaning of peaks and their angular positions given by RIMAPS analysis. A known surface pattern made on a sample of pure copper, mechanically ground, is used to study reproducibility, dependence on image quality and topography scale relative to pixel size and magnification. Samples of pure zinc, mechanically ground and chemically etched, were used to show the main features of RIMAPS analysis when characterizing a more complicated pattern on a real surface. All the studies performed under different conditions for observation and acquisition of images give strong evidence of the stability and robustness of RIMAPS as a technique for the characterization of topography.  相似文献   
26.
The classical spectral analysis of structural response to a gusty wind is applied to the prediction of fatigue damage as expressed by the rate of accumulation of Miner's quotient, using the rainflow algorithm to establish stress-range cycle counts. A general solution in chart form is given for the effect of the broad-band (quasi-static) part of the response spectrum, together with an algebraic formulation for its combination with the effect of narrow-band (quasi-resonant) response.A procedure for integration of the long-term expectation of Miner's quotient is indicated. It is concluded that quasi-static response alone is unlikely to pose a serious fatigue problem. With generally anticipated levels of dynamic response, fatigue damage is greatly increased, but can be controlled at acceptable levels by care to avoid features especially sensitive to fatigue.  相似文献   
27.
Sergei L. Shmakov 《Polymer》2002,43(4):1491-1495
The two-region Okada-Numasawa model for solutions of star-shaped polymers has been improved by means of a change in the integration order and introduction of a concentration-dependent and molar-mass-dependent Flory-Huggins interaction parameter (the second and third approximations of the Flory-Huggins theory). To overcome calculation difficulties, a special algorithm for computing coexistence curves of polymeric systems with an UCST has been used. The agreement between the experimental and calculated coexistence curves for the star-shaped polystyrene (PS)-cyclohexane system has been improved: the difference between Tcs is ∼0.33 K against ∼12 K as given by the original model.  相似文献   
28.
29.
Formulations for parametric circles and spheres in terms of rational Gaussian (RaG) curves and surfaces are introduced. With the proposed formulations, a full circle is generated by interpolating a closed RaG curve to the vertices of an equilateral triangle, and a full sphere is generated by interpolating a closed RaG surface to the vertices of an octahedron with equilateral triangular faces. Generation of circles and spheres in this manner is very intuitive and easy to remember as the weights are all 1 and the nodes are all unique and uniformly spaced.  相似文献   
30.
Matlab语言强大的运算、仿真能力,被广泛用在液压控制系统中。利用Matlab语言可以进行液压特性曲线的绘制,液压控制系统稳定性的检测,也可以进行液压控制系统的仿真。这里以两个实例,即单、双喷嘴挡板阀压力流量特性曲线的绘制,以及液压转矩放大器系统稳定性的检测,来说明它的强大的功能。  相似文献   
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