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We report an efficient, reusable, and selective 6-aminothiouracil (ATA)-modified Zr­(IV)-based adsorbent (defined as UiO-66-ATA­(Zr)) for lead ion removal in water. The adsorption equilibrium time and the maximum sorption capacity of UiO-66-ATA­(Zr) for Pb­(II) are, respectively, 120 min and 386.98 mg/g at pH 4 and 298 K. The Pb­(II) removal rate reaches 96% at 60 min and exceeds 99% at the equilibrium state in the pH range of 2.0–5.8. Hill and pseudo-second-order models can well describe the sorption process. Pb­(II) adsorbing onto UiO-66-ATA­(Zr) is an irreversible, favorable chemisorption process with multimolecule participation and film diffusion control. The calculations of density functional theory, the experimental results, and the characterization analyses suggest that the binding mechanisms are the chelation and ion-exchange/electrostatic interactions between hydroxyl/amino/sulfhydryl groups of UiO-66-ATA­(Zr) and Pb­(II). Besides, UiO-66-ATA­(Zr) has a better affinity to Pb­(II) than the coexisting ions in water and an excellent repeatability at eight cycles of adsorption. Moreover, the thermodynamic study shows that UiO-66-ATA­(Zr) adsorbing Pb­(II) is an endothermic reaction. Thus, UiO-66-ATA­(Zr) is a prospective sorbent for Pb­(II) removal under the initiative of environmental protection and water purification, and this work may also provide an idea for industrial catalysis.

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Coherence measures and their operational interpretations lay the cornerstone of coherence theory. In this paper, we introduce a class of coherence measures with α-affinity, say α-affinity of coherence for α ∈ (0, 1). Furthermore, we obtain the analytic formulae for these coherence measures and study their corresponding convex roof extension. We provide an operational interpretation for 1/2-affinity of coherence by showing that it is equal to the error probability to discrimination a set of pure states with the least square measurement. Employing this relationship we regain the optimal measurement for equiprobable quantum state discrimination. Moreover, we compare these coherence quantifiers, and establish a complementarity relation between 1/2-affinity of coherence and path distinguishability for some special cases. *

The characteristics of oxy-fuel combustion with recycled flue gas are different with air combustion in several aspects, such as char structure and reactivity. A high concentration of CO 2 has important implications on char characteristics. The present study is a further effort to extend our knowledge of the effect of sodium on the char crystalline structure and combustion reactivity in the presence of a high concentration of CO 2 . Coal samples include a bituminous coal and a lignite coal. H-and Na-form coal samples are prepared separately. The following conclusions are drawn. The charÀCO 2 yields are obviously less than the charÀN 2 yields, especially for lignite coal. The gasification reaction is a very important factor in a CO 2 atmosphere. When the pair of H-and Na-form coal samples are compared, experimental results show about 5 and 3% of the decrease in the charÀCO 2 yield was observed for Nadoped lignite and bituminous coal reacting in a CO 2 atmosphere, respectively. During the pyrolysis and gasification of the bituminous coal, the BrunauerÀEmmettÀTeller (BET) surface area and total pore volume of charÀCO 2 are much larger than those of charÀN 2 . When char combustion was under a reaction-controlled regime during thermogravimetric analysis, the char reactivity indexes of the four chars from the bituminous coal were almost the same. When the pair of chars formed in N 2 and CO 2 atmospheres was compared, charÀCO 2 is much more reactive than charÀN 2 for both the H-and Na-form lignites. The higher reactivity of charÀCO 2 implies that the catalysis of the inorganic matter, including the added Na, as well as higher surface area played a significant role in char reactivity.