Combustion characteristics and kinetics of anthracite with added chlorine

The combustion process of Yangquan anthracite (YQ) with the addition of 0.045wt%, 0.211wt%, 1.026wt%, and 2.982wt% chlorine was investigated using a thermogravimetric method from an ambient temperature to 1173 K in an air atmosphere. Results show that the YQ combustion characteristics are not significantly affected by an increase in chlorine content. Data acquired for combustion conversion are then further processed for kinetic analysis. Average apparent activation energies determined using the model-free method (specifically the KAS method) are 103.025, 110.250, 99.906, and 110.641 kJ/mol, respectively, and the optimal kinetic model for describing the combustion process of chlorine-containing YQ is the nucleation kinetic model, as determined by the z(α) master plot method. The mechanism function of the nucleation kinetic model is then employed to estimate the pre-exponential factor, by making use of the compensation effect. The kinetic models to describe chlorine-containing YQ combustion are thus obtained through advanced determination of the optimal mechanism function, average apparent activation energy, and the pre-exponential factor.     

基于DEMD与多尺度几何分析的图像压缩方法

研究了基于方向预测偏差度以及模式经验分解(DEMD)的图像分解方法.对于分解所得到的图像高频信息提出采用基于JPEG 2000的9-7小波进行压缩,而对其他的图像分量则实施Bandelet变换处理.从而得到一种高保真图像压缩新方法.仿真实验表明,本文方法在恢复图像质量方面优于广为采用的JPEG 2000以及原有的几何多尺度分析方法.     

IL-8-induced L-selectin shedding regulates its binding kinetics to PSGL-1

L-selectin plays a crucial role in inflammation cascade by initiating the tethering and rolling of leukocytes on endothelium wall. While many L-selectin molecules are rapidly shed from the cell surface upon activation, the remaining membrane-anchored L-selectin may still play an important role in regulating leukocyte rolling and adhesion with different binding kinetics. Here we developed an in vitro model to activate Jurkat cells via interlukin-8 （IL-8） and quantified the two-dimensional （2D） binding kinetics, using a micropipette aspiration assay, of membrane-anchored L-selectin to P-selectin glycoprotein ligand 1 （PSGL-1） ligand coupled onto human red blood cells （RBCs）. The data indicated that L-selectin shedding reduced the amount of membrane-anchored L-selectin and lowered both its reverse and forward rates. These results suggested that the rolling dynamics of activated leukocytes was determined by two opposite impacts： reducing the surface presentation would enhance the rolling but lowering the kinetic rates would decrease the rolling. This finding provides a new insight into understanding how L-selectin shedding regulates leukocyte rolling and adhesion.     

Influence of contaminations on combustion kinetics in hydrogen-fueled engine

In this work, we investigate the combustion of hydrogen fuel through the wind tunnel tests. Two kinds of fuel, the pure hydrogen and the hydrogen-ethene mixture, have been chosen to heat the oxygen-enriched air. It is found that the stable pressure in the engine combustor and the thrusts is almost the same in two cases. A valuable feature we revealed is that the heating pattern of hydrogen and ethene mixture leads to a considerable delay of the establishment of the wall pressure in the combustor, compared with the pure hydrogen case. This phenomenon implies a longer ignition delay time for the mixture case. The shorter ignition delay resulting from the hydrogen heater is attributed to the continuity of chain propagation and the exclusion of the less active C-containing radicals.     

活体细胞图像斑点的自动提取和跟踪方法

采用基于小波分解多尺度系数乘积的方法检测图像中的斑点,同时提出了基于贪婪思想的可以自动处理目标分裂和合并的模型,综合目标信息对轨迹进行跟踪.对Adaptor和Clathrin图像分割取得了比较理想的结果,Adaptor图像中的目标识别率98.61%,Clathrin图像中目标识别率达到97.65%.新的跟踪算法在处理轨迹合并和分裂方面有明显优势,对斑点跟踪效率达到为98.05%.结果表明,新的算法能有效地识别和跟踪图像中的斑点.从生物学角度,更有效的识别有助于更好地理解质膜的通道运输机制以及因为其不正常工作引起的疾病.     

磷酸盐分解钼酸钙的热力学

针对磷酸盐分解钼酸钙的过程,根据同时平衡原理和质量守恒定律,绘制了25℃时Ca-Mo-P-H_2O体系溶解组分的lgC-pH图,以及不同总磷浓度条件下溶液中总钙、总钼的lgC-pH图和钼酸钙稳定区. 结果表明,在溶液中总磷浓度一定的条件下,随着pH的增大体系中会依次出现H_2MoO_4(s)、CaMoO_4(s)、Ca5(OH)(PO_4)_3(s)和Ca(OH)_2(s)稳定存在的区域. 总磷浓度直接影响到钼酸钙的分解过程,随着总磷浓度的增加,钼酸钙的稳定区域不断减小甚至消失,使得钼酸钙更加易于分解, 因此溶液中总钼浓度不断增大,而总钙浓度不断降低;但总磷浓度过高会导致溶液中残留游离含磷离子过高. 从热力学角度来看,在钼酸钙分解过程中,添加磷酸盐比碳酸盐更加有利于钼酸钙的分解.     

基于数据流优化的BPEL流程分割方法

BPEL描述的业务流程在跨组织的企业应用集成与协作中扮演着重要角色.目前BPEL流程主要采用集中式的执行方式,但是集中式执行的BPEL流程性能不高并且不能满足动态流程管理的需求.提出了一种基于数据流优化的BPEL流程分割方法,以支持BPEL流程的分散化执行.BPEL流程经过变换被表示成PFG图,提出数据流方程对PFG图进行数据流分析,扩展复制传播算法优化PFG图的数据流.最后按照流程中的角色分割BPEL流程.实验数据表明优化分割后的业务流程的吞吐率、响应时间等方面的性能有较大提高.     

微通道内甲醇重整反应的LB方法

利用格子Boltzmann方法对微通道内甲醇水蒸汽重整制氢反应过程进行模拟,建立了双速率动力学平行反应机理的格子演化模型。分析了边界温度和进口流速的变化对甲醇转化率,氢气和一氧化碳的出口含量以及通道中的最大温差的影响。当边界温度和进口速度一定时,分析了整个反应过程中各组分的变化情况。结果表明,在水醇比,边界温度以及进口速度分别为1.3、523 K、0.1 m/s的情况下:甲醇出口转化率最高达94.36%;氢气的含量为0.0989;CO的含量为0.0095%。发现随边界温度升高,进口流速的减小,CO的含量会进一步增加。     

OFDM信道估计的复矩阵分解及FPGA实现

应用基于奇异值分解的OFDM（orthogonal frequency dirision multiplexing）信道估计降低计算量的同时能够保证信道估计的性能,研究OFDM信道向量自相关矩阵奇异值分解的FPGA(field programmable gat array)实现,提出一种复共轭对称矩阵奇异值分解的FPGA简化实现方法,将复矩阵的奇异值分解转换为实矩阵的奇异值分解,并根据实对称矩阵SVD(singular value decomposition)的特点对Systolic阵列结构进行改进,减少了所占用的资源。最后设计了高阶实对称矩阵SVD的FPGA实现方案,仿真结果表明该设计方案是可行的,能够应用于OFDM信道估计系统。