基于禁忌搜索的晶体位置谱分割与校准方法

为满足不同规格晶体探测器对分割校准晶体条响应事件位置数据的需求，开发了一种以禁忌搜索算法为核心，结合UDP数据帧、二维高斯模型及光导折射率的位置信息分割校准方法。实验结果表明，本方法在溢出率为5%时，峰谷比可达1218，空间分辨率达17 mm，晶体条响应位置识别准确度高达99%，滤除了引发伪峰的噪声，避免了过分割问题。在面对多种规格晶体阵列的位置谱时，本方法能依照阵列规格将晶体条区域的响应自动校准编号并输出晶体位置查找表，实现响应事件的精确校准。     

Ablation behavior of (TiZrHfNbTa)C high-entropy ceramics with the addition of SiC secondary under an oxyacetylene flame

The ablation behavior of high-entropy ceramics (HECs) was investigated in this study using an oxyacetylene flame at 2000 °C. Spark plasma sintering was used to construct a dense HEC (TiZrHfNbTa)C with a 20 vol% of SiC addition (HEC-20SiC). The densification of HEC-20SiC can be improved to a certain extent by adding SiC particles, increasing the hardness of HEC-20SiC to up to 24.6 GPa, and the crack deflection observed through the addition of SiC particles were considered to be the strengthening and toughening mechanisms. After ablation, Hf₆Ta₂O₁₇, Ti_5.1Ta_4.9O₂₀, Nb₂Zr₆O₁₇, TaZr_2.75O₈, and SiO₂ can be detected on an ablated surface and HEC-20SiC possesses the minimum mass ablation rate (?1.9 mg s^?1) and line ablation rate (2.1 μm s^?1) among the comparative ceramics. On the one hand, the SiC phase forms gaseous CO, CO₂, and SiO as well as viscous SiO₂ during ablation and some part of the heat can be dissipated by the evaporation of gaseous CO, CO₂, and SiO; further, pore defects can be healed by viscous SiO₂, thus inhibiting the diffusion of reactive oxygen species. On the other hand, the HEC phase with a lattice-distortion caused by single-phase solid-solution can effectively inhibit the invasion of reactive oxygen species and the outward migration of metal atoms. The invasion rate of reactive oxygen is considered to be the main step during HEC-20SiC ablation, and it is believed that higher principal component HECs can improve ablation performance even further.     

微孔碳材料修饰的隔膜用于高性能锂硫电池

锂硫电池具有较高的能量密度,是有发展前景的能量存储体系之一。但“穿梭效应”严重制约了锂硫电池的实际应用,为解决该问题,本文通过简单的一步热解法合成了孔径均匀的微孔碳材料,探究了微孔碳材料修饰隔膜后对锂硫电池性能的影响。结果表明,制备的微孔碳材料孔径集中在0.56nm左右,修饰隔膜后不仅能够有效抑制“穿梭效应”的产生,还有利于加快锂离子的传输,确保正极一侧溶解的多硫化物的再次利用。在0.1C的电流密度下,采用微孔碳材料修饰隔膜的电池首次放电比容量为1359mAh/g,循环100次之后容量能保持在966mAh/g,而修饰之前的传统聚丙烯隔膜,循环100次之后的比容量仅为409mAh/g;在1C的电流密度下循环500圈后,采用微孔碳材料修饰隔膜的电池容量保持率为88%,表现出优异的循环稳定性。     

基于系统动力学的分布式可再生能源激励机制分析

国家和地方的清洁能源发展政策促进了清洁能源装机容量的井喷式增长,碳交易和绿色证书机制虽然都可以对清洁能源发展起到促进作用,但对于分布式和集中式的促进作用则显示出较大的不同。在分析证书价格传导过程的基础上,采用系统动力学方法从集中式可再生能源参与的批发市场和分布式可再生能源参与的零售市场两个层面进行建模,建立了碳排放权交易市场、绿色证书交易市场和电力市场三个宏观市场间的交互模型和包含分布式可再生能源的配电网模型。算例仿真了两种机制下集中式可再生能源、分布式可再生能源的发展轨迹,讨论了碳交易和绿色证书机制的价格设置对分布式可再生能源发展的影响,验证了提出的效益分享机制对分布式可再生能源的促进作用。     

纳米 SiO2 表面“点击”化学法接枝共聚物

目的提高纳米Si O2在有机溶剂及树脂基体中的分散性。方法首先利用普通自由基聚合的方式制备苯乙烯及马来酸酐共聚物(PSMA),再与丙炔醇反应,在分子链上引入多个炔基,然后利用硅烷偶联剂KH560改性纳米Si O2,之后与叠氮化钠反应,在纳米Si O2粒子表面引入多个叠氮基团,最后将带有多个炔基的分子链通过"点击"化学接枝到纳米Si O2表面。结果酸碱反滴定法测得聚合物中马来酸酐的质量分数为26.5%。凝胶渗透色谱测得聚合物数均相对分子质量为36200,相对分子质量分布为1.39。红外表征显示,聚合物上带有多个炔基,纳米Si O2粒子表面带有多个叠氮基,经过24 h"点击"化学反应,聚合物成功接枝到粒子表面,同时叠氮基吸收峰消失。热重(TG)结果表明,接枝率为32.83%。扫描电镜分析表明,接枝聚合物后,粒子的分散性增强。结论分子链上含有多个炔基的共聚物(PSMA)通过"点击"化学反应成功接枝到了纳米Si O2粒子表面,不会引起粒子间的交联,可以明显提高纳米Si O2粒子在有机溶剂中的分散性。     

A cutting sequence optimization algorithm to reduce the workpiece deformation in thin-wall machining

A thin-wall part of lower stiffness can be subject to significant deformation during its cutting process. This study proposes a cutting process optimization algorithm to reduce the workpiece deformation. First, the volume to be removed is divided into a set of blocks. The proposed algorithm starts from the finished workpiece shape, with all the blocks removed. The objective of the proposed algorithm is to find a sequence of adding the blocks, such that the workpiece deformation is always smaller than the given threshold value when the cutting forces is imposed at each step. The workpiece deformation at each step is simulated by using the FEM (finite element method) simulation. By inverting the sequence of adding the blocks, the optimized sequence to remove the blocks can be obtained. Additionally, the block size can be modified to reduce the axial depth of cut to further reduce the workpiece deformation, or to increase the radial depth of cut to enhance the efficiency. Experiments are conducted to confirm the effectiveness of the algorithm to reduce the maximum workpiece deformation during the entire cutting process.     

恒速浇注工序时间控制方法

恒速浇注是炼钢生产组织及工艺质量控制水平的重要指标,工序时间控制则是实现恒速浇注的前提。利用流水线技术原理分析了恒速浇注的工序时间条件,提出采用延迟第一个任务的方法来实现恒速浇注并给出了最佳延迟值,实践表明该方法可行。     

微波技术在冶金中的应用

介绍了微波加热原理及其优点,综述了微波技术在冶金过程中的应用状况,以及微波协同其他外场技术在冶金中的最新应用状况,展望了未来外场技术强化冶金过程的发展趋势与研究重点。     

高低频混合方法估算角反射器阵RCS

结合高频算法处理复杂目标雷达散射截面(RCS)的思路,提出了利用HFSS仿真软件得到的数据计算复杂目标RCS,给出了计算式,并运用Matlab验证计算公式的适用性。     

通货膨胀影响因素及发展趋势分析

摘要：本文分析了近期经济运行中影响通货膨胀的主要因素货币供应量、人民币汇率和外汇储备，认为我国短期内不会出现通货膨胀，但中期存在通货膨胀可能性较大，同时指明了未来时期通货膨胀的发展趋势。