电感耦合等离子体原子发射光谱法测定钛合金中的硼

建立电感耦合等离子体原子发射光谱法测定钛合金中硼元素的分析方法。采用盐酸–氢氟酸–硝酸溶解钛合金样品,选择208.889 nm为硼的分析谱线,通过基体匹配法消除基体钛的干扰。在优化条件下对钛合金样品进行测定,线性相关系数大于0.999 0,硼的定量下限为0.000 5%,测定结果的相对标准偏差不大于3.00%(n=11),硼的加标回收率为95.00%～102.50%。该方法快速、准确,可以满足实际生产中钛合金样品的测定要求。     

电感耦合等离子体质谱法测定苦瓜药材中16种无机元素

建立电感耦合等离子体质谱法测定苦瓜药材中16种无机元素。苦瓜样品采用微波消解处理,电感耦合等离子体原子发射光谱法检测。待测元素的质量浓度在各自的线性范围内与发射光强度线性关系良好,线性相关系数不小于0.999,各元素的检出限在0.001～1.000 mg/kg,定量限在0.003～3.300 mg/kg,回收率在82.9%～112.5%,测定结果的相对标准偏差为0.62%～2.32%。测定样品中的无机常量元素Mg,Ca,Fe,K等含量大于137 mg/kg,有害元素Hg,Pb,Cd,As等含量小于0.5 mg/kg。该方法分析速度快,灵敏度高,适用于苦瓜药材中无机元素测定。     

轴流透平与排汽系统间流场相互作用研究

为了研究轴流透平与非轴对称排汽系统流场间的相互作用,对带有单级透平的300/600MW汽轮机排汽系统模型内流场进了模型实验,并用商用软件CFX数值计算了实验工况下带有全周叶栅通道的单级透平与排汽系统内的耦合流场.对比实验与数值模拟结果,二者吻合较好.通过对实验和数值结果分析发现,排汽系统内的非轴对称流场使透平叶栅通道内流动沿周向发生变化,扩压器内出现大的流动分离,排汽系统内总压损失增大,静压恢复系数为负.     

提高气冷涡轮气热耦合计算精度的措施

温度场计算的准确性对气冷涡轮的设计影响极大.实际的气冷涡轮在运行状态下,存在多种物理现象:冷气带来的燃气组分变化、湍流、转捩、温度边界层的发展变化、热辐射等.而在数值计算中,计算结果也要受到网格质量的影响.采用自编程序、商业CFD软件对某两级气冷涡轮、C3X以及MARK Ⅱ叶片进行计算,分别描述冷气组分变化、计算网格、湍流模型以及转捩温度场模拟精度的影响;同时定性分析温度边界层复合性质与辐射换热对温度计算的影响.得出在气热耦合计算中,考虑上述因素的影响是很有必要的.     

轴流式水轮机转轮流固耦合计算

在利用轴流式水轮机全流道三维非定常湍流数值计算和利用弹性力学非稳态有限元法计算轴流式水轮机转轮叶片动态的应力和应变的基础上,利用弱耦合算法完成了轴流式水轮机在有粘有旋条件下的流固耦合计算,得到了叶片的动态应力和动态应变,并对结果进行了讨论.     

Characteristic Numbers of Matrix Lie Algebras

A notion of characteristic number of matrix Lie algebras is defined, which is devoted to distinguishing various Lie algebras that are used to generate integrable couplings of soliton equations. That is, the exact classification of the matrix Lie algebras by using computational formulas is given. Here the characteristic numbers also describe the relations between soliton solutions of the stationary zero curvature equations expressed by various Lie algebras.     

Phase Transitions in Neutron Stars Within Modified Quark-Meson Coupling Model

K^- condensation and quark deconfinement phase transitions in neutron stars are investigated. We use the modified quark-meson coupling model for hadronic phase and the MIT bag model for quark phase. With the equation of state （EOS） solved self-consistently, we discuss the properties of neutron stars. We find that the EOS of pure hadron matter with condensed K- phase should be ruled out by the redshift for star EX00748-676, while EOS containing unpaired quark matter phase with B1/4 being about 180 MeV could be consistent with both this observation and the best measured mass of star PSR 1913 ＋ 16. But if the recent inferred massive star among Terzan 5 with M 〉 1.68M is confirmed, all the present EOSes with condensed phase and deconfined phase would be ruled out.     

Ground State Properties of Superheavy Nuclei in Macroscopic-Microscopic Model

The ground state properties of superheavy nuclei are systematically calculated by the macroscopic- microscopic （MM） model with the Nilsson potential. The calculations well produced the ground state binding energies, α-decay energies, and half lives of superheavy nuclei. The calculated results are systematically compared with available experimental data. The calculated results are also compared with theoretical results from other MM models and from relativistic mean-field model. The calculations and comparisons show that the MM model is reliable in superheavy region and that the MM model results are not very sensitive to the choice of microscopic single-particle potential.     

Enhanced Synchronization of Intercellular Calcium Oscillations by Noise Contaminated Signals

We consider the dynamics of locally coupled calcium oscillation systems, each cell is subjected to extracellular contaminated signal, which contains common sub-threshold signal and independent Gaussian noise. It is found that intermediate noise can enhance synchronized oscillations of calcium ions, where the frequency of noise-induced oscillations is matched with the one of sub-threshold external signal. We show that synchronization is enhanced as a result of the entrainment of external signal. Furthermore, the effect of coupling strength is considered. We find above-mentioned phenomenon exists only when coupling strength is very small. Our findings may exhibit that noise can enhance the detection of feeble external signal through the mechanism of synchronization of intercellular calcium ions.