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以4-溴-1,8-萘酐为原料合成了新型萘酰亚胺衍生物N-正己基-4-苄胺基-1,8-萘酰亚胺(HBN),通过NMR和 MS 表征了其结构。利用荧光光谱研究它对铁离子(Ⅲ)的识别作用。实验显示,在 C2 H5 OH/H2O (φ:1/1)体系中,当Fe3+浓度为4×10-7~1×10-2 mol·L-1时,HBN荧光强度随Fe3+浓度增加大幅度下降。线性回归方程为:F0/F=623.2532cFe3++0.9642(R2=0.9963)。常见金属离子,如Ca2+,Na+, Cu2+,Zn2+,Pb2+,Co2+,Ni2+,Mn2+及Fe2+等,均不干扰HBN对Fe3+的识别。结果表明,HBN对Fe3+具有较好的选择性和灵敏度。 相似文献
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设计并合成了萘酰亚胺衍生物N-正己基-4-[2-(3-苯基硫脲)-乙氨基]-1,8-萘酰亚胺(HTN),通过NMR和MS表征了其结构。利用荧光光谱法研究了HTN对苦味酸(PA)的识别作用。研究发现,在C2H5OH/H2O (2:1)体系中,HTN荧光强度随PA浓度的增加而大幅度下降。PA浓度在1×10-6~5×10-4 mol·L-1范围内时,猝灭率(I0-I)/I0与[PA]0.5呈线性关系,R2=0.995 5。常见苯系物,如苯胺、苯甲醛、三硝基甲苯、苯酚、苯乙烯、吡啶、对甲苯磺酸、甲苯、硝基苯及氯苯等均不干扰HTN对PA的识别。结果表明,HTN对PA具有较好的选择性和灵敏度。 相似文献
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IntroductionTherheologyofcolloidaldispersionisofinterestinmanyphysicalandtechnologicalproblems,andforthisreasonithasbeenstudiedextensively,especiallywhenthesystemcanbedescribedbythelinearNavier_Stokesequations[1~3].Colloidaldispersioncanbesubdividedinto… 相似文献
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胶体是自然界和工业应用中的常见对象。胶体领域的一个中心理论问题是如何根据胶体系统的微结构来确定胶体的流变性质。由于处理多粒子系统边值问题的困难,现有的胶体理论都局限于低颗粒浓度。该文中发展了变换场方法,用该方法可以计算含胶体颗粒的不可压缩粘滞流体的有效粘滞系数,颗粒可以是固体也可以是流体。在低颗粒浓度,该理论预测与爱因斯坦关于悬浮体的公式以及Taylor关于乳浊液的公式完全吻合。在高颗粒浓度,该文的结果与Nunan和Keller的结果相一致,其方法可以用于预测非球形颗粒悬浮体的有效粘滞系数。 相似文献
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Under an external uniform electric field, the dielectric response of graded
cylindrical composites having generalized dielectric profile inclusions is
investigated. The generalized dielectric profile of graded cylindrical
inclusion is expressed in the form, $\varepsilon _i (r)=c(b+
r)^k\e^{\beta r}$ where $r$ is the radial variable of the cylindrical
inclusions and
$c$, $b$, $k$ and $\beta $ are parameters. The local potential solution of
generalized dielectric profile graded composites is derived by means of the
power series method and the effective dielectric response is predicted in
the dilute limit. Moreover, from the result of generalized profile, the
analytical solutions of local potentials and the effective responses of
graded composites having three cases of dielectric profiles, i.e., the
exponential profile $\varepsilon_\i (r)=c\e^{\beta r}$, the general power
law profile $\varepsilon_\i (r)=c(b+r)^k$ and the profile $\varepsilon_\i
(r)=cr^k\e^{\beta r}$, are sorted out, respectively. In the dilute limit,
our exact results are used to test the validity of differential effective
dipole approximation (DEDA) for estimating the effective response of graded
cylindrical composites, and it is shown that the DEDA is in excellent
agreement with the exact result. 相似文献