Advanced Materials Research Vols. 383-390

Abstract: In the actual disassembly decision-making, people may concern multiple evaluation parameters, such as disassembly time and disassembly energy. In order to deal with multiple parameters evaluation problem, the expected model of time-energy trade-off problem of product disassembly process is presented in this paper. Simultaneously, taking the typical transmission device for example, its stochastic time-energy trade-off problem is analyzed. The results provide guidance for disassembly practice.

Abstract: The experimental is carried out in the normal air atmosphere by calcining CaCO₃ and using the scan electricity speculum and N2 adsorption apparatus to research the ventage structure of the calcinate CaO at 860°C.Analyzing on fractal dimension of different calcination temperature, heating rate and residence time. Thorough the pore structure of CaO which is a porous substance, using “dynamic pervasion modulus” to analyse the Calcium-based sorbent’s gas-solid pervasion transferring quality reaction when it is calcined in the furnace. Using the “dynamic pervasion modulus” and revising the expression of the SO₂ adsorption quality in vulcanizing reaction.

Abstract: High molecular weight, readily soluable copolymer was prepared from 9,9-di (2-thienyl-hexyl) fluorene (TF) 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-di octyl fluorene and narrow band gap comonomer 2,3-dimethyl- 5,8-(5-bromo)-dithien-2-yl-quinoxalines (DTQU) using pallad- ium catalyzed Suzuki coupling methods. To compare the copolymer to this without thiophene in the C9 side chain of fluorene, the copolymer from DOF and DTQU was synthesized. The electrochemical, optical and photovoltaic properties of the copolymers were studied. The absorption spectra of the copolymers measured in thin films display two absorption peaks. The power conversion efficiency achieved in the device configuration ITO/PEDT/FT- DTQU:PCBM (1:2)/Al is 0.85% with open-circuit voltage (Voc) 0.8V. Further improvement by manipulating polymer/electrode interface and further investigation of more polyfluorene copolymers with narrow band gap aryl-hetero cycle units on the side chain is in progress.

Abstract: On the basis of the proposed computing method for the low-cycle fatigue lifetime of a supercharged boiler steam drum, and the two computing principles, which super-pose the resultant stress of the internal pressure stress and the radial temperature difference heat stress at the boiler steam drum fatigue checking point, whose influences on the low-cycle fatigue lifetimes of one supercharged boiler steam drum were calculated, compared and analyzed, there out the computing principle of a supercharged boiler for superposing the resul-tant stress of the above-mentioned two stresses was opened out. The simplified computing method, which will be applied to calculating the alternating stress range in a stress cycle at the supercharged boiler steam drum fatigue checking point, was also derived from combining the design feature of a super-charged boiler steam drum with theory analysis, and com-paring with the Chinese Standard computing method, this computing method not only can reduce the calculational work-load, but also can simplify the calculational steps greatly. Thereby the proposed computing method for the low-cycle fatigue lifetime of a supercharged boiler steam drum was also further simplified.

Abstract: Roadway bolt supporting, which relates the equations such as ground stress, mechanical property of surrounding rock and bolt supporting structure, is an engineering problem of rock and structure coupling. Three-dimensional developing entry bolt supporting aided design system was developed by using ANSYS finite element software. Supporting function mechanics of coal roadway bolt supporting was analyzed and calculated. The effects of bolt supporting under similar conditions on roadway deformation, stress and displacement field around the roadway was mainly studied. The simulation results were applied in bolt supporting engineering of a coal mine 2395 entity coal roadway, and excellent supporting results were obtained which provides good experience for further generalization and application.

Abstract: This article according to the ShengLi Open-pit Coal Mine landslide and the slope project special details, used the FLAC numerical calculus analysis software to conduct the research to the landslide cataclysm mechanism, has carried on the optimized analysis to the reinforcement plan.Has obtained the pre-stressed anchor rope frame beam + high pressure splitting grouting reinforcement plan government landslide most superior processing plan through the numerical calculus, thus active control ShengLi Open-pit Coal Mine slope distortion destruction.

Abstract: A class of multi-variable decoupling control algorithm for aero-engines is mainly studied In this paper. Firstly, the mechanism of ADRC decoupling control algorithm is elaborated and discussed in detail. Secondly, an ADRC controller for some turbofan engine's nonlinear component-level model is designed to solve two-loop control problem according to the basic principle of ADRC. Compared with ALQR (Augmented Linear Quadratic Regulator) controller in full flight envelope, enough numerical verification tests about ADRC controller have carried out. Finally, simulation results show that the closed-loop system based on the ADRC decoupling controller has better disturbance rejection capability than the ones based on ALQR controller.

Abstract: Through the synthetically analysis of the composite index method for evaluation of rock burst rating, the limitation of this method is discussed. Mines have various burst development characteristics, and geological condition and mining technical factors decide different rock burst weights greatly. So this paper prefers an optimal case based on analytic hierarchy process, using cooperation matrix to decide the influence weight of the factors on the burst, and synthetized with the actual impact risk index, which makes the method more precise and objective to evaluate the burst rating to provide a scientific basis for safe investment of the mine.

Abstract: Through the field test on the laboratory building foundation pit engineering of Northeastern University at Qinhuangdao, the distribution and variation rule of steel stress and pile moment is researched and analyzed in the process of the deep foundation pit excavation. The result shows that foundation pit excavation and applied prestressed anchor are the main factors of pile internal force change, furthermore, the latter is more effective than the former. Meanwhile, the influence of top beam to steel stress and moment of pile head can not be ignored especially. The zero position of steel stress and pile moment are basically same, which lies under foundation pit bottom. The use of limit equilibrium method more economical than elastic subgrade method in design over foundation pit bottom, however, which is opposite under it.

Abstract: A method to determine the condensing temperature set point of air-cooled refrigeration system with an electronic expansion valve was discussed in this paper. This set point is fixed for a specific system and is based on the flow characteristic of the installed electronic expansion valve in variant opening and pressure drop. As common sense, at constant differential between condensing pressure and evaporating pressure, larger opening of expansion valve allows more refrigerant flowing through the expansion valve into evaporator. This feature offers an opportunity to lower the condensing temperature via increasing opening of expansion valve to enhance refrigeration efficiency and in the same time designed cooling capacity can be maintained at low ambient temperature. In this case it is supposed that the installed electronic expansion valve’s capacity was larger than the evaporator’s, and in fact that occurs frequently in refrigeration system designing. The benefits of this method could include: the capacity of electronic expansion valve is fully utilized, the refrigeration system will operate at a lower condensing pressure and the power consumption of compressor can decrease, hence the improvement of system efficiency is predictable.