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991.
芳环羟基化HPLC分离荧光法检测Cu(Ⅱ)-H2O2体系中产生的·OH 总被引:1,自引:3,他引:1
采用L-苯丙氨酸为探针,使用液相色谱分离荧光检测(FLD)和荧光分光光度分析(FS)两种方法平行检测Cu(Ⅱ)-H2O2 体系中产生的·OH.试验采用的激发波长277 nm,发射波长306 nm.体系在反应前后的荧光变化,可反映·OH产生量.对FLD与FS所得数据进行了比较分析,结果显示两种方法具有较高一致性.FS使用混合体系检测,易对荧光的产生造成干扰,而FLD法没有干扰. 相似文献
992.
New constructions of regular disjoint distinct difference sets (DDDS) are presented. In particular, multiplicative and additive DDDS are considered. 相似文献
993.
994.
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996.
Observations of sampling are often subject to rounding, but are modeled as though they were unrounded. This paper examines
the impact of rounding errors on parameter estimation with multi-layer ranked set sampling. It shows that the rounding errors
seriously distort the behavior of covariance matrix estimate, and lead to inconsistent estimation. Taking this into account,
we present a new approach to implement the estimation for this model, and further establish the strong consistency and asymptotic
normality of the proposed estimators. Simulation experiments show that our estimates based on rounded multi-layer ranked set
sampling are always more efficient than those based on rounded simple random sampling. 相似文献
997.
Analytic Hardy and BMO spaces on the quantum torus are introduced. Some basic properties of these spaces are presented. In particular, the associated H 1-BMO duality theorem is proved. Finally, we discuss some possible extensions of the obtained results. 相似文献
998.
This paper investigates the relationship between topology and generalized rough sets induced by binary relations. Some known results regarding the relation based rough sets are reviewed, and some new results are given. Particularly, the relationship between different topologies corresponding to the same rough set model is examined. These generalized rough sets are induced by inverse serial relations, reflexive relations and pre-order relations, respectively. We point that inverse serial relations are weakest relations which can induce topological spaces, and that different relation based generalized rough set models will induce different topological spaces. We proved that two known topologies corresponding to reflexive relation based rough set model given recently are different, and gave a condition under which the both are the same topology. 相似文献
999.
The primary goal of this paper is to present a comprehensive study of the nonlinear Schr?dinger equations with combined nonlinearities of the power-type and Hartree-type. Under certain structural conditions, the authors are able to provide a complete picture of how the nonlinear Schr?dinger equations with combined nonlinearities interact in the given energy space. The method used in the paper is based upon the Morawetz estimates and perturbation principles. 相似文献
1000.
Zhi Kong Lifu WangZhaoxia Wu 《Journal of Computational and Applied Mathematics》2011,236(6):1521-1530
There are many uncertain problems in practical production and life which need decisions made with soft sets and fuzzy soft sets. However, the basis of evaluation of the decision method is single and simple, the same decision problem can obtain different results from using a different evaluation basis. In this paper, in order to obtain the right result, we discuss fuzzy soft set decision problems. A new algorithm based on grey relational analysis is presented. The evaluation bases of the new algorithm are multiple. There is more information in a decision result based on multiple evaluation bases, which is more easily accepted and logical to one’s thinking. For the two cases examined, the results show that the new algorithm is efficient for solving decision problems. 相似文献