基于克隆选择算法的非线性优化迭代学习控制；Clonal selection algorithm based nonlinear optimal iterative learning control

为实现对模型不确定的有约束非线性系统在特定时间域上输出轨迹的有效跟踪,将改进的克隆选择算法用于求解迭代学习控制中的优化问题。提出基于克隆选择算法的非线性优化迭代学习控制。在每次迭代运算后,一个克隆选择算法用于求解下次迭代运算中的最优输入,另一个克隆选择算法用于修正系统参考模型。仿真结果表明,该方法比GA-ILC具有更快的收敛速度,能够有效处理输入上的约束以及模型不确定问题,通过少数几次迭代学习就能取得满意的跟踪效果。

Isospin dependence of the nuclear equation of state near the critical point

We discuss experimental evidence for a nuclear phase transition driven by the different concentrations of neutrons to protons. Different ratios of the neutron to proton concentrations lead to different critical points for the phase transition. This is analogous to the phase transitions occurring in He-4-He-3 liquid mixtures. We present experimental results that reveal the N/A (or Z/A) dependence of the phase transition and discuss possible implications of these observations in terms of the Landau free energy description of critical phenomena.

THE ISOSPIN DEPENDENCE OF THE NUCLEAR PHASE TRANSITION NEAR THE CRITICAL POINT

The experimental results reveal the isospin dependence of the nuclear phase transition in terms of the Landau Free Energy description of critical phenomena. Near the critical point, different ratios of the neutron to proton concentrations lead to different critical points for the phase transition which is analogous to the phase transitions in He-4-He-3 liquid mixtures. The antisymmetrized molecular dynamics (AMD) and GEMINI models calculations were also performed and the results will be discussed as well.

Determination of Point of Zero Charge of Tunisian Kaolinites by Potentiometric and Mass Titration Methods

This paper deals with determining points of zero charge of natural and Na+-saturated mineral kaolinites using two methods: (1) acid-base potentiometric titration was employed to obtain the adsorption of H+ and OH- on amphoteric surfaces in solutions of varying ionic strengths in order to determinate graphically the point of zero net proton charge (PZNPC) defined equally as point of zero salt effect (PZSE); (2) mass titration curve at different electrolyte concentrations in order to estimate PZNPCs by interpolation and to compare with those determined by potentiometric titrations. The two methods involved points of zero charge approximately similar for the two kaolinites between 6.5-7.8, comparable to those reported previously and were in the range expected for these clay minerals. The comparison of potentiometric surface titration curves obtained at 25 °C and those published in the literature reveals significant discrepancies both in the shape and in the pH of PZNPCs values.

zero point of charge of cupric hydroxide and surface area determination by dye adsorption

zero point of charge of freshly precipitated cu(oh)2 has been determined to lie at pH 7.7 by means of microclectrophoresis technique. Day aged hydroxide shows an acid zpc shift to pH 7.3. these experimental values approximate the equivalence points of cu+ and oh_ ,which can be estimated from the solubility diagram constructed fo gu(oh)2 and cuo.

Comparison of salt titration and potentiometric titration methods for the determination of zero point of charge

the salt ritration metod was evaluated as a method to determine zpc in comparison with the potentiometric titration method for 26 soil with variable charge clays,i.e.,Oxisols and Ultisols from Thailand and Andisols from Japan. In addition to the determination of ST-pH0 as the zero point of charge, a calculation procedure was adopted here in order to acquire more information from the titration curve . fuithermore, for the purpose of cross-checking of zpc determined by the pt method, the st procedure was successively applied to the samples analyzed by the pt method.

Biochemical properties of C78SC96S rhFGF-2: A double point-mutated rhFGF-2 increases obviously its activity

Fibroblast growth factor-2 (FGF-2) is a multifunctional polypeptide that affects many cellular functions and phenomena. The wild-type recombinant human fibroblast growth factor rhFGF-2(W) and the mutant C78SC96S rhFGF-2(M) were expressed in Escherichia coli and their products were purified. The results by the means of fluorescence spectroscopy and CD spectrums, suggested that due to its decreased hydrophobicity rhFGF-2 is not deposited as an inclusion body. The mitogenic activity of the expressed rhFGF-2(M) on 3T3 fibroblasts was shown to be 10-fold more than the expressed rhFGF-2(W) of which the biological activity was a little less than that of the standard rhbFGF(W), indicating that the increased biological activity was due to the change of its secondary structure, dimerization and affinity binding to FGF receptor (FGFR).

Conformational and orientational analyses of 2,2 '-bithiophene under interaction of external electric field constructed by point charges

The fully relaxed single-bond torsional potentials and orientation-related rotational potentials of 2,2'-bithiophene (BT) under the interaction of an external electric field (EF) constructed by point charges have been evaluated with semi-empirical AMI and PM3 calculations. The torsional potentials are sensitive to both EF strength and direction. While the EF is parallel to the molecular long axis, the torsional barrier around C-x-C-x' bond obviously rises with increasing the EF strength, whereas the relative energies of syn and anti minima show a slight change. The interaction between the EF and the induced dipole moment has been proposed to elucidate this observation. On the other hand, the relative energy difference between the syn and anti minima shows an obvious change, while the EF is perpendicular to the molecular long axis. This feature has been ascribed to the interaction between the EF and the permanent dipole moment of BT. Furthermore, conformational and orientational analyses in two dimensions have been carried out by changing the torsional and rotational angles in the different EF. The conformation and orientation of a gas-phase BT in the EF are governed by both the above factors.