Ding-投射模和粘合

首先, 研究由Ding-投射模构成的同伦范畴, 并且在这些同伦范畴中构造出一些粘合; 其次, 利用t-结构和粘合的关系得到相关的稳定t-结构.     

Petroleum-contaminated soil extent recorded by δ15N and δ13C of plants and soils

Petroleum contamination in terrestrial environments caused by industrial activities is a significant problem that has received considerable attention. Carbon and nitrogen isotopic compositions (δ13C and δ15N) effectively describe the behavior of plants and soils under petroleum contamination stress. To better understand plant and soil responses to petroleum-contaminated soil, δ13C and δ15N values of the plants (Trifolium repens, Leguminosae with C₃ photosynthesis pathway, and Agropyron cristatum with C₄ photosynthesis pathway) and the soil samples under one-month exposure to different extents of petroleum contamination were measured. The results showed that petroleum contamination in the soil induced the soil δ15N values to increase and δ13C values to decrease; from 1.9‰ to 3.2‰ and from ?23.6‰ to ?26.8‰, respectively. However, the δ13C values of Agropyron cristatum decreased from ?29.8‰ to ?31.6‰, and the δ13C values of Trifolium repens remained relatively stable from ?12.6‰ to ?13.1‰, indicating that they have different coping strategies under petroleum-contaminated soil conditions. Moreover, the δ15N values of Trifolium repens decreased from 5.6‰ to 0.8‰ near the air δ15N values under petroleum-contaminated soil, which implies that their nitrogen fixation system works to reduce soil petroleum stress. The δ13C and δ15N values of Agropyron cristatum and Trifolium repens reflect changes in the metabolic system when they confront stressful environments. Therefore, stable isotopic compositions are useful proxies for monitoring petroleum-contaminated soil and evaluating the response of plants to petroleum contamination stress.     

n-李代数的Hypo-幂零理想

研究n-李代数的Hypo-幂零理想,及具有5维极大Hypo-幂零理想的所有可解3-李代数的结构.证明可解非幂零n-李代数一定存在Hypo-幂零理想,且其幂零根基的余维数等于1.给出可解非幂零3-李代数的极大Hypo-幂零理想与3-李代数的维数关系.对具有一类特殊5-维极大次幂零理想的可解3-李代数的每一类3-李代数,分...     

蕴含强(p,q)哈密尔顿性的几个条件

利用路收缩技术,证明了,如果有向图D满足下列条件中的任何一个,(1)最小半度δ0(D)≥(n+p+q)/2;(2)D是(p+q+1)强连通有向图,且d+(x)+d+(y)+d-(u)+d-(v)≥2(n+p+q)-1,这里,x,y是任意控制顶点对,u,v是任意被控制顶点对;(3)D的弧数超过(n-1)2+q2+p;那么D是强(p,q)哈密尔顿的.     

Steinberg群中的H元素和W元素

研究了任意环的Steinberg群中的两类特殊的元素,这有助于估计环的K2群.特别地,给出了一些关于稳定秩1环的K2群的新结果.     

Bear根的一种新的刻划

本文引入了环R的平方为零的理想、弱m序列及次强幂零元，并由此给出了环R的Bear根的一种新的刻划．     

Banach序列空间的强端点

得到了Ｂａｎａｃｈ序列空间ｌｐ（Ｅ）其单位球面上的点ｘ０＝（ｘ０（ｉ））为强端点的充分必要条件是ｘ０（ｉ）‖ｘ０（ｉ）‖是Ｂａｎａｃｈ空间Ｅ的单位球面的强端点，进而指出ｌｐ（Ｅ）为中点局部一致凸的充分必要条件是Ｂａｎａｃｈ空间Ｅ是中点局部一致凸的。     

剩余格蕴涵代数中准素理想的研究

在剩余格蕴涵代数中,提出了素理想和准素思想的概念,证明了包含核的理想的格蕴涵同态像仍是理想,并研究了准素理想与素理想的性质.讨论了准素思想与素理想、准素理想与其格蕴涵同态像之间的关系.     

关于火电机组应用热经济学分析法的改进建议

在很多文献中，构造热经济学补充方程时，一般都将表面加热器的燃料多线流当作双线流看待，文章对此提出了不同看法和改进意见，并用实例说明采用改进的补充方程原则更具科学合理性。     

右对合广群中的上粗子广群与上粗理想

在右对合广群中引入了粗糙集的基本理论，定义了右对合广群中的上近似算子和下近似算子，以及上粗子广群与上粗理想等概念，研究了它们的性质，得到了一些有意义的结果。这些结果将粗糙集代数性质的研究扩展到右对合广群这个代数系统中。