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顺序注射-氢化物发生-原子荧光光谱法测定马氏珠母贝中镉的含量 总被引:1,自引:0,他引:1
镉是对人体有害的重金属元素之一,是慢性蓄积性毒物,对肾脏、骨骼、肺、肝、神经系统以及血液系统均可产生毒性,并且具有致癌、致畸和致突变的作用[1]。随着现代工业化的迅猛发展,海洋环境特别是贝类的生长环境受到重金属的污染日益严重。而贝类是具有很强富集能力的滤食性底栖生物,使到其体内重金属镉含量极易超标[2]。马氏珠母贝又名合浦珠母贝,是我国南方海水珍珠养殖的主要品种,主要分布在广东、广西和海南三省。其贝肉是一 相似文献
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牡蛎是我国主要的食用贝类之一,含有丰富的蛋白质及微量元素,其中硒含量因生长环境影响而变化很大。硒是人体必需的微量元素,为保证人体健康,每天必须摄入一定量的硒,摄入过量或不足量的硒都会对人体产生不利影响。目前对于痕量硒的检测方法有石墨炉原子吸收光谱法、氢化物发生-原子荧光光谱法(HG-AFS)、电感耦合等离子体原子发射光谱法、分光光度法、电化学分析 相似文献
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红外光谱法分析二元聚合物 总被引:1,自引:0,他引:1
在偶氮二异丁腈(AIBN)引发下,苯乙烯和丙烯腈的自由基发生聚合而产生苯乙烯-丙烯腈二元聚合物,制取了一系列丙烯腈不同含量的聚合物。选取705cm^-1和2240cm^-1。两个红外吸收峰分别测定苯乙烯和丙烯腈。苯乙烯吸光度与丙烯腈吸光度之比值和聚合物中丙烯腈摩尔分数的倒数呈线性关系,由这些数据回归建立工作曲线。 相似文献
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CH2体系激发态的量子化学研究 总被引:1,自引:0,他引:1
本文使用SCF,MCSCF,SOCI方法计算了CH2的基态和三个激发态。讨论了总量,稳定性,平衡几何构型和振动频率等性质。所得结果与实验和理论计算的文献值相吻合,并且预言了一个新激发态c^1∑^+g的性质。 相似文献
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The localized molecular orbital (LMO) theory is used to study the reaction mechanism of the isomerization reaction: H_3PO→H_2POH. The energy transition state (TS) of the reaction is also obtained by Powell's mehtod using 6-31G basis set. The resluts show that the lone pair electrons of oxygen atom play an forortant role in this reaction. 相似文献
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Using the -mapping topological theory, we study the topological structure of vortex lines in a two-dimensional generalized Gross-Pitaevskii theory in (3+1)-dimensional space-time. We obtain the reduced dynamic equation in the framework of the two-dimensional Gross-Pitaevskii theory, from which a conserved dynamic quantity is derived on the stable vortex lines. Such equations can also be used to discuss Bose-Einstein condensates in heterogeneous and highly nonlinear systems. We obtain an exact dynamic equation with a topological term, which is ignored in traditional hydrodynamic equations. The explicit expression of vorticity as a function of the order parameter is derived, where the δ function indicates that the vortices can only be generated from the zero points of Φ and are quantized in terms of the Hopf indices and Brouwer degrees. The -mapping topological current theory also provides a reasonable way to study the bifurcation theory of vortex lines in the two-dimensional Gross-Pitaevskii theory. 相似文献