Performance of PAHs emission from bituminous coal combustion

Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.     

多目标决策问题的交互式保守最优方法

对多目标决策问题提出了交互式保守最优方法,并给出了数字例子,本方法具有对决策者所提问题很简单,以及能自动保持前后一致等特点。     

关于n—维矩阵群的注记

本文证明了域 F 上的 n 阶2m—维矩阵环 M_(2,n)(F)同构于域 F 上的 n~m 阶全矩阵环F~(n~m×n~m),以及域 F 上的 m-维矩阵空间 M_(m,n)(F)同构于域 F 上的 n~m-维向量空间F~(n~m).     

聚氨酯固定化米根霉发酵乳酸动力学研究

采用聚氨酯继载体，对米根霉（Rhizopus oryzae）进行自吸附固定化，在鼓泡塔反应器中对以葡萄糖和混合糖（葡萄糖和木糖）的乳酸发酵动力学进行了研究。建立了固定化米根霉以葡萄糖、木糖与葡萄糖的混合糖为碳源的L－乳酸发酵动力学模型，模型计算结果与实验数据较为符合。     

Co-APDC共沉淀预富集、、微量试样的FAAS法测定海水中铁、锌

建立了Co-APDC共沉淀预富集、微量试样脉冲雾化的火焰原子吸收光谱(FAAS)测定海水中Fe、Zn的方法。Fe、Zn测定的相对标准偏差分别是2.3％、0.4％;检出限为 22.5 pg、2.5 pg;回收率为 95.9±3％、95.5±2％。本法采用自制进样杯与喷雾器连接,具有装置简单、通用性好,快速简便、精确等优点。与Co-APDC共沉淀预富集的石墨炉测定法配合,可用于测定天然水中不同浓度的多种重金属。     

K-S检验在裂隙岩体统计均质区划分中的应用

采用K-S检验法,提出考虑裂隙岩体迹长的新方法来划分岩体的统计均质区,计算对比样本各属性的累积频率、K-S统计量和K-S临界值,从而验证对比样本之间的显著性差异,以此实现了对裂隙岩体的统计均质区的划分.通过对云南省马吉水电站左岸坝肩某一高程相邻两个平洞不同风化带的岩体结构统计均质区划分,计算结果表明,相邻两个平洞在弱风化下限、微风化及新鲜岩带内具有统计相似性,可以划分为统计均质区,而在弱风化上限不具有统计相似性;单个平洞在各个风化带内不具有统计相似性.此外,该方法可以运用到小样本裂隙的统计均质区划分中.     

基于氢储能的含大规模风电电力系统经济调度

针对由大规模风力发电并网带来的消纳困难问题,文章利用由碱式电解槽、储氢罐、氢氧燃料电池构成的氢储能系统将弃风转换成氢气储存起来,用以满足外界氢气负荷需求或于负荷高峰期发电补充上网。文章先对风电出力的不确定性和氢储能系统进行建模。为了降低传统鲁棒优化求解的保守度,利用考虑保守度可调的鲁棒优化盒式集合描述风电出力。在此基础上,以降低弃风和提高系统总体的经济性为目标,建立了基于氢储能的含大规模风电电力系统经济调度模型。算例表明,文章所建立的优化调度模型兼顾求解的鲁棒性和经济性,并且可以显著减少弃风、降低系统的总成本。     

Attraction and stability for neutral stochastic functional differential equations

The main aim of this paper is to establish several new criteria on the attractor for the solutions of neutral stochastic functional differential equations. A kind of ψ-function is introduced to our discussion, and some results on the attractor for the product of the ψ-function and the solutions are obtained. As a byproduct, a number of new criteria on asymptotic stability are also shown. Biography: CEN Liqun(1975–), female, Ph.D. candidate, research direction: theory and applications of stochastic differential equations.