An important reference criterion for the selection of GSSP

A study on the relationship between biostratigraphy and sequence stratigraphy in several designated global boundary stratotypes shows that the best way may be to take the GSSP at a point coincident with the base of the first widespread Leading Group biozone above the first flooding surface (FFS) of the relevant third-order sequence. It is suggested that the first flooding surface of the sequence should be an important reference criterion for the selection of GSSP. As the base of the first widespread Leading Group biozone chosen for the definition of GSSP could not be lower than the first flooding surface of the referred sequence, the latter surface may be an important criterion for the recognition and correlation of the chronostratigraphic boundaries.     

Molecular characterization of a K+ channel blocker in the scorpionButhus martensii Karsch

K⁺ channel blockers of scorpion venoms are of important value in studying pharmacology and physiology of specific K⁺ channel of cells. Based on the amino acid sequences of BmP01 previously characterized as a small-conductance Ca²⁺-activated K⁺ channel blocker, two “back to back” degenarate primers have been designed and synthesized for inverse PCR strategy, its full-length cDNA has been cloned from the venom gland of the Chinese scorpionButhus martensii. The cDNA is composed of 3 parts: 5′ UTR, ORF and 3′ UTR. The flanking sequence of translation initiation codon ATG is AAAATGA, which is highly conserved in scorpion Na⁺ channel toxin and protozoan genes, suggesting that these genes may have followed a common mechanism for translation initiation. The 3′ UTR contains poly(A) signal AATAAA. The open reading frame encodes a precursor of 57 residues with a signal peptide of 28 residues and a mature peptide of 29 residues. The signal peptide is rich in hydrophobic amino acid residues and its length is significantly different from that of the determined scorpion Na⁺ channel toxin. The deduced amino acid sequence of mature peptide is completely consistent with BmP01 previously determined by primary structure analysis.     

巨野煤田含煤地层层序单元划分

运用当代层序地层学的理论和方法体系,通过对区内近２００个钻孔岩心的详细研究,根据石岩－二叠系沉积旋回特点,系统地分析了沉积体系、层序地层及其内部构成特点,建立了研究区陆表海盆地和陆相盆地的层地层格架。研究表明,巨野煤田石岩－二叠系共划分为２个构造层序,７个Ⅲ级层序和４２个准层序。     

多值单调型算子不动点带有误差项的Ishikawa迭代逼近

在一致光滑Ｂａｎａｃｈ空间中,证明了带有误差项的Ｉｓｈｉｋａｗａ迭代序列强收敛于一类多值单调型算子的唯一不动点。这些结果改进和推广了Ｄｕｎｎ,Ｃｈｉｄｕｍｅ,Ｄｅｎｇ－Ｄｉｎｇ,丁协平,Ｃｈａｎｇ－Ｔａｎ等人的最新结果。     

变进位记数制与伪随机序列的产生

本文提出了一种通用的变进位记数制 ,以及其中的一种进位制──自然进位制 .并方便地用于解决序列的全排列问题 .在此基础上 ,提出了两种产生伪随机数序列的方法 :码控字节交换法和码控位交换法 .作者希望这种变进位记数制能在其它应用领域发挥其作用 .     

1997的粤东海域棕囊藻赤潮原因种18SrDNA基因分析

近年来,随着沿海城市工农业的高速发展,大量含有氮、磷等营养元素的污水排入大海,导致海水富营养化的加剧,有毒藻类赤潮分布范围及出现频率明显增加.1997年7～12月我国东南沿海水面首次发生大规模的棕囊藻类(Ｐｈａｅｏｃｙｓｔｉｓ)有毒赤潮,其持续时间长,危害大,给水产...     

关于Smarandache序列中的素数问题

解决了有关Smarandache序列中的素数个数问题     

船舶并联同步发电机逆序短路研究

对并联运行船舶同步发电机,当待并发电机逆序投入运行电网引起的短路过程进行分析计算,给出同步发电机电枢电流和脉动电磁力矩的计算表达式。     

极大允许序列的框架结构

本文研究了极大允许序列的性质,给出了极大允许序列的框架结构。     

计算Bezout阵的惯性的快速算法及应用

在本文中,提供了一个计算Ｂｅｚｏｕｔ矩阵惯性的快速无分式算法,并能确定出给定整系数代数方程的不同实根个数及不同对共轭复根对数。