Lω-空间中的ω-Urysohn分离性

在Lω-空间中引入分子网和理想的ωθ*-极限点、ωθ*-聚点等概念,证明ω-Urysohn空间中分子网和理想的ωθ*-极限点均唯一等特征性质,并证明ω-Urysohn分离性是可ω-遗传的,在(ω1,ω2)-同胚和(ω1,ω2)θ-同胚映射下是拓扑不变的,在满层条件下是任意可乘的,而且是R.Lowen意义下好的推广等性质。     

若干图的卡氏积的距离谱和距离能量(英文)

G是顶点集为{v_1,v_2,…,v_n}的连通简单图,G_1,G_2,…,G_n是有限图。联并图G[G_1,G_2,…,G_n】是按如下方式在G_1UG_2U…UG_n上加边而成的图:在G_i和G_j之间的任何两个顶点间加边,若v_i和v_j在G中相邻.[7]给出了两个距离正则图的卡氏积的距离谱.本文计算了联并图和距离正则图的卡氏积及两个联并图的卡氏积的距离谱.在此基础之上,我们得到了两个利用联并图与非同谱距离正则等能量图作卡氏积及联并图作卡氏积构造非同谱等距离能量图族的方法.     

电子束诱导单壁碳纳米管不稳定的新观察

利用透射电镜在室温下对不同形态的单壁碳纳米管进行了原位电子束辐照研究.研究发现:在相同的辐照条件下随着辐照时间(或辐照剂量)的增加,两端固定的单壁碳纳米管径向收缩,且收缩速率越来越快;相同直径的轴向弯曲的单壁碳纳米管比平直的单壁碳纳米管更加不稳定;一端固定另端自由的单壁碳纳米管轴向收缩,但其直径基本不变.利用单壁碳纳米管纳米曲率效应和能量束诱导非热激活效应,对上述单壁碳纳米管不稳定性现象进行了新的、合理的解释.     

On two unimodal descent polynomials

The descent polynomials of separable permutations and derangements are both demonstrated to be unimodal. Moreover, we prove that the $\gamma$-coefficients of the first are positive with an interpretation parallel to the classical Eulerian polynomial, while the second is spiral, a property stronger than unimodality. Furthermore, we conjecture that they are both real-rooted.     

Random walks and the effective resistance sum rules

In this paper, using the intimate relations between random walks and electrical networks, we first prove the following effective resistance local sum rules:

     

具脉冲效应和Beddington-DeAnglis功能反应时滞周期捕食系统

研究一类具有脉冲效应和Beddington-DeAnglis功能反应的时滞周期捕食系统,给出系统持续生存和周期解存在的条件.证明了在无时滞情况下,周期解是全局稳定的.     

番石榴叶提取物的鉴定及其抗菌作用

采用纸片扩散法对番石榴叶提取物进行体外抗菌试验研究,以了解其抗菌谱.结果表明番石榴叶提取物中存在有效抗菌成分,其中以乙醇提取物中白念珠菌、甲醇提取物中大肠埃希菌高度敏感.     

A study of using luminophore-doped silica nanoparticles as fluorescent probe in protein microarray assay

A convenient method for the synthesis of tris(2,2′-bipyridyl) dichlororuthenium(II) hexahydrate-doped amino-modified double-layer silica nanoparticles is presented in this paper. The synthesized nanoparticles are uniform and photostable, and can be well dispersed in a water solution. Proteins could be directly immobilized onto these nanoparticles by a simple coupling process without losing their biological activities. These nanoparticles were further used as fluorescent probes in protein microarray assay for the quantitative detection of protein. The results obtained by these nanoparticles, with the detection limit of as low as 3.5 μg/mL, were much better than those involving the use of conventional FITC probe. Translated from Chinese Journal of Analytical Chemistry, 2006, 34(9): 1227–1230 (in Chinese)     

龙岩煤不同宏观煤岩组分的颗粒及其燃烧性质实验研究

用浮选法分选出3个密度档、代表不同宏观岩相的龙岩煤颗粒，进行工业分析、元素分析和煤岩分析；并进一步通过扫描电镜结合压汞实验分析颗粒的结构，通过热天平实验研究不同宏观煤岩组分的燃烧性质。结果表明，(1)龙岩煤颗粒的煤岩主要由镜质组组成。其中，亮煤富含镜质组，密度相对较低，挥发分极少、固定碳高达80％以上；暗煤富含矿物质成分，密度极高但含碳量却很少，热值很低，接近于原煤中的矸石。灰煤中惰性组的量是三种岩相中最多的，其工业分析性质与原煤接近；(2)龙岩煤颗粒结构致密，密度在1.6g/cm3以上。颗粒中绝大多数孔隙的孔径在1μm以下。其中亮煤颗粒表面光洁致密，内部孔隙以亚微孔(0.01μm<d<0.10μm)居多，大孔径较少，比表面积较大；暗煤颗粒的表面孔隙较发达，内部结构相对较蓬松，颗粒中细孔、微孔、亚微孔都存在；而灰煤颗粒中的孔隙最不发达，以超微孔(d<0.01μm)为主；(3)不同宏观煤岩组分龙岩煤的着火温度相近，约580℃；但燃尽温度相差较大：亮煤最高，大于800℃；暗煤最低，两者相差约100℃；(4) 龙岩煤不同宏观煤岩颗粒的反应性按亮煤、煤(混煤)、灰煤、暗煤依次递减，亮煤的反应性最好，暗煤的反应性最差。     

Laser photolysis of interaction of poly-guanylic acid (5′) with anthraquinone-2-sulfonate

The electron transfer reaction between triplet anthraquinone-2-sulfonate and poly- guanylic acid (5′) in CH3CN-H2O (97:3) has been investigated by 248 nm (KrF) laser flash photolysis. The transient absorption spectra and kinetics obtained from the interaction of triplet anthraquinone-2-sulfonate and poly[G] demonstrate that the primary ionic radical pair, radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate have been detected simultaneously. The free energy changes in the process of the electron transfer were also calculated.