Influence of Control Parameters on the Competition Between Spiral Waves and Target Waves

In this paper we systematically investigate the influence of control parameters on the competition results between spiral waves and target waves. Driving frequency f , amplitude A and injection area n of the input signals are three important parameters and the competition results between spiral waves and target waves are influenced by these three parameters remarkably. Based on these understandings we can control spiral waves effectively by suitable combination these parameters to generate faster target waves. And the effective controllable parameter regions are also studied.     

微波水热时间对C/C复合材料结构和抗氧化性能的影响

以磷酸、B4C和Al2O3为原料,采用一种新的微波水热法对C/C复合材料基体进行了抗氧化改性,重点研究了微波水热时间对改性试样物相组成、微观结构和抗氧化性能的影响。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能量色散谱仪(EDS)及X射线光电子能谱(XPS)对改性后试样进行了表征。结果表明:改性后复合材料表面覆盖了一层由熔融态的HPO3、B2O3和结晶的Al(PO3)3、微量B4C粒子组成的涂层。经60~120 min的微波水热改性,复合材料的抗氧化性能随着微波水热处理时间的延长而改善,达到一定程度后,其变化不再明显。微波水热处理100 min后的试样抗氧化性能最佳,在600℃静态空气气氛下氧化16 h后,氧化失重仅为9.5×10-4 g.cm-2,氧化失重速率维持在4.46×10-5 g.cm-2.h-1的极低水平。     

硫与Mn2O3空心球的复合结构及其在锂硫电池中的应用

在水热条件下,以碳球为模板合成了Mn₂O₃空心球,并用作锂硫电池的载硫基底材料。测试结果表明载硫量为51%的Mn₂O₃-S复合材料显示了较高的比容量,良好的循环稳定性和倍率性能。循环100圈后,最终可逆容量仍保持657 mA·g^-1,证明该Mn₂O₃空心球是一种有潜力的载硫基底材料。     

液态结构与性质关系Ⅲ——剩余键理论模型

利用剩余键的思想, 通过数学推导, 建立定量描述金属熔体结构与黏度关系的物理模型, 提出黏度的微观结构变化特性为熔体剩余键结构尺寸d的演变; 应用建立的模型理论计算液相线以上一定温区镁熔体和铝熔体的运动黏度, 得到函数关系式分别为v_Mg=3.17×10^-7+3.04×10^-7· d和v_Al=1.65×10^-7+1.05×10^-7·d, 这与采用坩埚扭摆振动法的实验测量结果相符合. 该模型从化学结合键角度揭 示了金属熔体的结构微观不均匀性及其黏度的微观物理本质, 为金属熔体黏度的理论计算提供了一种新的途径. 这对于深入认识液态金属的微观结构及其与宏观物性之间的关系具有重要意义.     

Network dynamics and its relationships to topology and coupling structure in excitable complex networks

All dynamic complex networks have two important aspects, pattern dynamics and network topology. Discovering different types of pattern dynamics and exploring how these dynamics depend or/network topologies are tasks of both great theoretical importance and broad practical significance. In this paper we study the oscillatory behaviors of excitable complex networks （ECNs） and find some interesting dynamic behaviors of ECNs in oscillatory probability, the multiplicity of oscillatory attractors, period distribution, and different types of oscillatory patterns （e.g., periodic, quasiperiodic, and chaotic）. In these aspects, we further explore strikingly sharp differences among network dynamics induced by different topologies （random or scale-free topologies） and different interaction structures （symmetric or asymmetric couplings）. The mechanisms behind these differences are explained physically.     

Dynamic investigation of the finite dissolution of silicon particles in aluminum melt with a lower dissolution limit

The finite dissolution model of silicon particles in the aluminum melt is built and calculated by the finite difference method, and the lower dissolution limit of silicon particles in the aluminum melt is proposed and verified by experiments, which could be the origin of microinhomogeneity in aluminum-silicon melts. When the effects of curvature and interface reaction on dissolution are not considered; the dissolution rate first decreases and later increases with time. When the effects of curvature and interface reaction on dissolution are considered, the dissolution rate first decreases and later increases when the interface reaction coefficient （k） is larger than 10 1, and the dissolution rate first decreases and later tends to be constant when k is smaller than 10-3. The dissolution is controlled by both diffusion and interface reaction when k is larger than 10-3, while the dissolution is controlled only by the interface reaction when k is smaller than 10-4.     

交叉概率对改进遗传算法运算速度影响的测试与分析

在现有文献基础上,通过理论分析,提出了交叉概率应取1.通过四个测试函数的测试结果,表明交叉概率越大,运算速度越快,平均运行代数越少,验证了通过理论分析提出的交叉概率应取1的科学性和可行性.同时克服了交叉概率难以确定以及确定交叉概率时缺少理论依据的不足.     

相位差与一般相干迭加态压缩特性

研究一般相干态的迭加态|ψ＞=a|β＞ beiψ|mβeiδ＞的k次方压缩特性,结果表明:一般相干态的迭加态和量子涨落的k次方压缩,在m=1时可表为k≠2nπ/δ,此处n是整数;在m≠1时,压缩的次方数可以是偶数也可以是奇数;当δ=π时,无论m[m∈(0.∞)]取何值均存在奇次方压缩,当δ=π/2时,无论m取何值均存在奇次方压缩和偶次方压缩.这说明参数相位差δ对一般相干态的k次方压缩的次方数起关键性的作用.     

阿托品选择电极的研制和应用

报道了一种阿托品选择性电极的研制和应用，该电极是将对阿托品敏感的聚氯乙烯膜涂敷于ｐＨ玻璃电极球部表面而制成。在０．１０ｍｏｌ／Ｌ，磷酸盐冲浓度（ｐＨ４．０）中，所制电极对阿托品的Ｎｅｒｎｓｔ响应线性范围为１．７０×１０＾－５～２．００×１０＾－２ｍｏｌ／Ｌ阿托品，响应斜率为５５．８ｍＶ，电极响应时间小于４５ｓ，使用寿命大于６个月，而且具有制作简单，使用方便的特点，已将该电极应用于硫酸阿托品制剂中测     

摩擦点火Ti-V-Cr阻燃钛合金燃烧产物的组织特征

采用摩擦氧浓度实验方法, 结合原位观察、扫描电镜、能谱仪和X-射线衍射分析, 系统研究Ti-V-Cr 阻燃钛合金燃烧产物的微观组织形貌、燃烧反应过程的合金元素分布规律及微观机理. 结果表明: Ti-V-Cr 阻燃钛合金燃烧过程发出闪亮耀眼的白光, 具有典型金属燃烧的火焰特征. 燃烧产物主要有TiO₂, V₂O₅和Cr₂O₃三种氧化物, 该混合氧化物以分散颗粒和致密连续体存在. 分散颗粒为规则的球形; 致密连续燃烧产物的微观组织具有分区特征, 从合金基体至燃烧表面依次为过渡区、热影响区、熔凝区和燃烧区. 其中, 过渡区存在一些微小的颗粒状凸起, 且有一定方向性; 热影响区中形成大量V基固溶体相和少量的Ti基固溶体相, V基固溶体相上存在Ti的含量远高于基体的针状析出物; 熔凝区中, 大量的Ti基固溶体中存在少量的V基固溶体; 燃烧区主要为Ti, V和Cr的氧化物混合物. 热影响区的V基固溶体相降低了Ti元素向熔凝区的迁移速率, 减慢了燃烧区Ti与O的优先反应; 燃烧区形成的TiO₂, V₂O₅和Cr₂O₃混合氧化物和熔凝区O在Ti中大量固溶共同终止了O向合金基体的继续扩散, 从而使Ti-V-Cr阻燃钛合金表现出优异的阻燃功能性.