The strong cooperativity of dioxygen binding by dicobalt (II) diporphyrin compounds in nonaqueous solution at room temperature

Thermodynamic data were determined for the reversible binding of O₂ to two compounds of dicobalt(II) di(meso-tetra-phenyl)porphyrin derivatives with different lengths of diamidoaliphatic bridge (abbreviated to Co₂PP₈ and Co₂PP₄) in N,N-dimethylformamide at room temperature. The partial pressure of dioxygen necessary for half-oxygenation (P _1/2) and hill coefficient (n) at 298 K were determined as follows:P _1/2=54.2 kPa,n=2.0 for Co₂PP₈ andP _1/2=6.8 kPa,n=1.8 for Co₂PP₄, respectively. The rate equations of reversible oxygen binding by Co₂PP₈ were determined and the reaction path was proposed. The results of ther-modynamic and kinetic studies indicate that there exists strong cooperative effect during oxygenation of the compounds. The ESR observation reveals that the dioxygen complexes formed in the solutions are of superoxo (Co-O ₂ ⁻ ) type. Supported by the Research Foundation of the State Education Commission of China Zhou Xiaohai: born in 1962, Ph.D. Associate professor     

新型心肌显像剂^99mTcN—TBI的初步研究

在成功制备了（＾９９ｍＴｃ〈Ｎ）＾２＋核的基础上，通过配全交换反应制得放化纯大于９５％的＾９９ｍＴｃＮ－ＴＢＬ＾９９ｍＴｃＮ－ＴＢＩ在制备后室温放置９ｈ放化纯不变，分配系数Ｐ＝５０．５２小鼠实验结果显示：＾９９ｍＴｃＮ－ＴＢＩ，＾９９ｍＴｃＮ－ＴＢＩ和加叶温－８０的＾９９ｍＴｃＮ－ＴＢＩ（Ｔ）有明显不同的生物分布，特别是＾９９ｍＴｃＮ－ＴＢＩ（Ｔ）的早期肝摄取低，在静注后５ｍｉｎ心肝比为１．１５，     

不对称信息下序贯信贷决策问题研究

研究了在不对称信息信贷市场中，当银行与贷款企业致力于发展长期信贷关系时，银行的序贯信贷决策问题。分析了银行所采取的序贯信贷决策对于克服企业道德危害的作用，并将单阶段信贷决策问题与序贯信贷决策问题进行了比较，得出了在一定条件下，序贯信贷决策比单阶段信贷决策的社会福利性有所提高的结论。     

采用频域与空域结合的错误掩盖算法

提出了一种空域与频域相结合的错误掩盖算法。本算法利用损坏区域周围的纹理特性对不同的坏块区分别采用频域或空域的方法来恢复。频域方法利用离散余弦变换的一些性质，用部分ＤＣＴ系数来恢复原块；空域算法采用逐点恢复的方法。