| 1. |
- Labrador-Páez, Lucia, et al.
(author)
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pH dependence of water anomaly temperature investigated by Eu(III) cryptate luminescence
- 2020
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In: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 412:1, s. 73-80
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Journal article (peer-reviewed)abstract
- Although water has been extensively studied, not all of its unique properties have been fully understood. There is still controversy about the temperature at which hydrogen bonds are broken or weakened, producing the anomalous temperature dependence of many water properties. Different temperatures between 23 and 48 °C have been reported, but no study has scrutinized the reasons for this discrepancy. We suggest the determining role of pH in the alteration of the water anomaly temperature. We employed a luminescent europium trisbipyridine cryptate, which is highly sensitive to changes in the arrangement of water molecules and whose luminescence intensity and lifetime are not significantly influenced by variations over a broad pH range. Our results revealed an increase of the crossover temperature from circa 35 °C at pH 3.5 to circa 45 °C at pH 7 to 9, which explains the discrepancies of previous studies. The pH dependence of water anomaly temperature is an important property for a better understanding of water and water-based systems and applications.
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| 2. |
- Llewellyn, R. D. O., et al.
(author)
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Establishing the Maximum Collectivity in Highly Deformed N = Z Nuclei
- 2020
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In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 124:15
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Journal article (peer-reviewed)abstract
- The lifetimes of the first excited 2(+) states in the N = Z nuclei Zr-80, Y-78, and Sr-76 have been measured using the gamma-ray line shape method following population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.
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| 3. |
- Llewellyn, R. D. O., et al.
(author)
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Spectroscopy of proton-rich Zr-79 : Mirror energy differences in the highly-deformed fpg shell
- 2020
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In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 811
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Journal article (peer-reviewed)abstract
- Energy differences between isobaric analogue states have been extracted for the A = 79, Zr-79/Y-79 mirror pair following their population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. These are the heaviest nuclei where such measurements have been made to date. The deduced mirror energy differences (MED) are compared with predictions from a new density-functional based approach, incorporating isospin-breaking effects of both Coulomb and nuclear charge-symmetry breaking and configuration mixing.
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