N、N'-二乙基-N、N'-二苯基脲的萃取性能和二硝酸二(N、N'-二乙基-N、N'-二苯基脲)合铀酰(Ⅱ)配合物的合成、结构研究

O引言 铀和钍燃料后处理广泛采用三丁基磷酸酯(TBP)作为萃取剂来分离铀和钍.然而在辐照下,TBP的降解产物二丁基磷酸酯(DBP)和一丁基磷酸酯(MBP)对裂变元素如锆和铌有较强的配位能力.     

N、N′-二乙基-N、N′-二苯基脲的萃取性能和二硝酸二(N、N′-二乙基-N、N′-二苯基脲)合铀酰(Ⅱ)配合物的合成、结构研究

The extraction behavior of N,N′-diethyl-N,N′-dibenzenyl-urea (DEDBU) to Uranium(Ⅵ) and Thorium(Ⅳ) from nitric acid solution was studied by using xylene as diluent. The effects of aqueous HNO₃ concentration and ex-tractant concentration on the extraction distribution ratio of U(Ⅵ) and Th(Ⅳ) were studied, and the results show that the extraction behavior of the extractant to U(Ⅵ) is similar to tributyl phosphate (TBP), the solvation numbers for DEDBU and TBP are two, respectively. Under the experiment condition, the extractant does not show the extraction behavior to Th(Ⅳ), this result exhibits that the extractant has good application to separate U(Ⅵ) and Th(Ⅳ). The crystal structure of the complex UO₂(NO₃)₂[CH₂(CH₂)₂CONC₈H₁₇]₂ was determined by single crystal X-ray diffraction. Crystal data: C₂₄H₄₆N₄O₁₀U, triclinic, space group , a = 8.662(2)?, b= 10.07(2)?, c= 10.895(3)?, α = 103.77(2)°, β = 92.01(2)°, γ = 96.23(2)°, V= 915.7(4)?³, M_r = 934.78, Z= 1, D_c= 1.695 g·cm^-3, F(000) = 462, μ = 4.495mm-1, R= 0.0250, wR= 0.0591, observed reflec-tions 3566 (I>2σ(I)).The central uranyl ions is coordinated by six oxygen atoms, two of them are from the carbonyl groups of N,N′-diethyl-N,N′-dibenzenyl-urea molecules, and the other four are from two nitrate groups.     

人机界面的模糊多层次综合评价

人机界面(HCI)是影响多媒体软件设计质量的重要因素之一。由于人机界面设计本身的复杂性,使得对它的评价具有一定的难度。本文提出了采用定性和定量相结合的模糊多层次综合评价方法对软件的人机界面进行评价,并讨论了基于模糊语言的单因素定量评价方法和利用层次分析法(AHP)确定各评价因素的权重。