摘要：The aim of this study is to determine the effect of the main chemical components ofbiomass： cellulose, hemicel- lulose and lignin, on chemical kinetics ofbiomass pyrolysis. The experiments were designed based on a simplex- lattice mixture design. The pyrolysis was observed by using a thermogravimetric analyzer. The curves obtained from the employed analytical method fit the experimental data （R2 〉 0.9）. This indicated that this method has the potential to determine the kinetic parameters such as the activation energy （E~）, frequency factor （A） and re- action order （n） for each point of the experimental design. The results obtained from the simplex-lattice mixture design indicated that cellulose had a significant effect on Ea and A, and the interaction between cellulose and lignin had an important effect on the reaction order, n. The proposed models were then proved to be useful for predicting pyrolysis behavior in real biomass and so could be used as a simple approximation for predicting the overall trend of chemical reaction kinetics.

摘要：The cell performance and temperature gradient of a tubular solid oxide fuel cell with indirect internal reformer （IIR-SOFC） fuelled by natural gas, containing a typical catalytic packed-bed reformer, a catalytic coated wall reformer, a catalytic annular reformer, and a novel catalytic annular-coated wall reformer were investigated with an aim to determine the most efficient internal reformer system. Among the four reformer designs, IIR-SOFC containing an annular-coated wall reformer exhibited the highest performance in terms of cell power density （0.67 *** 2） and electrical efficiency （68%） with an acceptable temperature gradient and a moderate pressure drop across the reformer （3.53 × 10 5 kPa）. IIR-SOFC with an annular-coated wall reformer was then studied over a range of operating conditions： inlet fuel temperature, operating pressure, steam to carbon （S ： C） ratio, gas flow pattern （co-flow and counter-flow pattern）, and natural gas compositions. The simulation results showed that the temperature gradient across the reformer could not be decreased using a lower fuel inlet temperature （1223 K-1173 K） and both the power density and electrical efficiency of the cell also decreased by lowering fuel inlet temperature. Operating in higher pressure mode （1-10 bar） improved the temperature gradient and cell performance. Increasing the S ： C ratio from 2 ： 1 to 4：1 could decrease the temperature drop across the reformer but also decrease the cell performance. The average temperature gradient was higher and smoother in IIR-SOFC under a co-flow pattern than that under a counter-flow pattern, leading to lower overpotential and higher cell performance. Natural gas compositions significantly affected the cell performance and temperature gradient. Natural gas containing lower methane content provided smoother temperature gradient in the system but showed lower power density and electrical efficiency.

摘要：In a hard chromium electroplating process, a heat exchanger is employed to remove the heat produced from the high current intensity in an electroplating ***, a conventional U shape heat exchanger is installed in the bath, but it provides low heat ***, this study designs a novel W serpentine shape heat exchanger with identical heat transfer area to the conventional one for increasing heat removal *** performance of the heat exchange is tested with various flow velocities in a cross-section in range of 1.6 to 2.4 m·s^(-1).Mathematical models of this process have been formulated in order to simulate and evaluate the heat exchanger *** results show that the developed models give a good prediction of the plating solution and cooling water temperature, and the novel heat exchanger provides better results at any flow *** addition, the W serpentine shape heat exchanger has been implemented in a real hard chromium electroplating *** data collected have shown that the new design gives higher heat removal performance compared with the U shape heat exchanger with identical heat transfer area; it removes more heat out of the process than the conventional one of about 23%.

摘要：本文提出了全面学习和相量粒子群相结合的方法用于解决限定固有频率约束下的空间结构优化问题.通过将相量理论和全面学习策略相结合以提高粒子群算法的效率.在优化的过程中,一个所谓的相角采用了周期正弦和余弦函数给定义速度的关键参数建模使得速度可以从所有粒子前一步的最佳位置中选取.这个方法不但实现了粒子们可以快速学习并且在少量的计算中进行了在作用力和固有频率约束下结构杆件的安全性评估和优化尺寸分布.提出的优化设计方法成功解决了一些工程应用结构的基准设计问题,这证明了本文方法相对于最新元启发方法的准确性和稳定性.