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微波消解-氢化物发生-原子荧光法测定海蜇中的痕量砷和硒 总被引:14,自引:2,他引:12
建立了氢化物发生-原子荧光光谱法(HG-AFS)测定新鲜和腌制海蜇中痕量砷、硒的分析方法。采用冷冻干燥和微波消解相结合的方法处理样品,设定了最佳的样品处理条件和仪器测定条件,解决了消解液中过剩酸对测定的干扰问题,并对共存元素干扰情况进行了研究。利用加标回收试验,对分析方法进行了验证。实验结果表明,该方法具有简便、快速、灵敏、准确等特点,适合于含水量较高的生物样品的测定。 相似文献
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Hongbo S Zongsuo L Mingan S Shimeng S Zanmin H 《Colloids and surfaces. B, Biointerfaces》2005,43(3-4):221-227
Drought is a worldwide problem, seriously influencing plant (crop) productivity. Wheat is a stable food for 35% of the world population, and moreover, about 60% of land area on the globe belongs to arid and semiarid zone. Wheat drought resistance is a multi-gene controlling quantitative character and wheat final production in field is realized mainly by physiological regulation under the condition of multi-environmental factor interaction. Exploring drought resistance physiological mechanisms for different wheat genotypes is of importance to finding new drought resistance gene resources and conventional breeding, and the basis for wheat drought resistance biotechnological breeding and platform. Photosynthesis is the main component for physiological machinery of wheat assimilates conversion and wheat production. Investigation on photosynthetic characteristics of different wheat genotypes at soil water deficits also has other implications for refine physiological regulation of photosynthesis in fields and field management of crops in arid and semiarid areas. By pot-cultivating experiments, investigation of photosynthesis for 10 wheat genotypes at seedling stage and tillering stage at soil water deficits (75%FC, 55%FC and 45%FC, respectively) was conducted. The main results were as followed: developmental stages influenced wheat photosynthesis greatly and tillering stage played more roles; there were significant difference in the main photosynthetic parameters, photosynthesis rate (Photo), stomatal conductance (Cond) and transpiration rate (Tr), among 10 wheat genotypes; general photosynthesis and drought resistance in different wheat genotypes was related much to their domesticated origin soil water environment and selected generations and there was a photosynthetic threshold effect in terms of different wheat genotypes at soil water deficits. 相似文献
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The splitting of potential energy curves for the states
$X^{2}\Pi _{3/2}$, $^{2}\Pi _{1/2}$ and $A^{2}\Sigma ^{ +}$ of
hydroxyl OH under spin--orbit coupling (SOC) has been calculated by
using the SO multi-configuration quasi-degenerate perturbation theory
(SO-MCQDPT). Their Murrell--Sorbie (M--S) potential functions have been
derived, then, the spectroscopic constants for $X^{2}\Pi _{3/2}$,$^{
2}\Pi _{1/2}$ and $A^{2}\Sigma ^{ + }$ have been derived from the
M--S function. The calculated dissociation energies for the three states are
$D_{0}$[OH($X^{2}\Pi _{3/2})$]=34966.632cm$^{-1}$,
$D_{0}$[OH($^{2}\Pi _{1/2})$]=34922.802cm$^{-1}$, and
$D_{0}$[OH($A^{2}\Sigma ^{ + })$]=17469.794cm$^{-1}$, respectively. The
vertical excitation energy $\nu [ {{ }^2\Pi _{1/2} ( {\nu = 0}
) \to {X}{ }^2\Pi _{3/2} ( {\nu = 0} )} ] =
139.6{\rm cm}^{-{\rm 1}}$. All the spectroscopic data for the
$X^{2}\Pi _{3/2}$ and $^{2}\Pi _{1/2 }$ are given for the
first time except the dissociation energy of $X^{2}\Pi _{3/2}$. 相似文献
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