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1. Mechanistical study on the formation of hydroxyacetone (CH 3 COCH 2 OH), methyl acetate (CH 3 COOCH 3 ), and 3-hydroxypropanal (HCOCH 2 CH 2 OH) along with their enol tautomers (prop-1-ene-1,2-diol (CH 3 C(OH)CHOH), prop-2-ene-1,2-diol (CH 2 C(OH)CH 2 OH), 1-methoxyethen-1-ol (CH 3 OC(OH)CH 2 ) and prop-1-ene-1,3-diol (HOCH 2 CHCHOH)) in interstellar ice analogs

   https://doi.org/10.1039/d2cp03543j  

   Wang, Jia ; Marks, Joshua H. ; Turner, Andrew M. ; Nikolayev, Anatoliy A. ; Azyazov, Valeriy ; Mebel, Alexander M. ; Kaiser, Ralf I. ( January 2023 , Physical Chemistry Chemical Physics)

   We unravel, for the very first time, the formation pathways of hydroxyacetone (CH 3 COCH 2 OH), methyl acetate (CH 3 COOCH 3 ), and 3-hydroxypropanal (HCOCH 2 CH 2 OH), as well as their enol tautomers within mixed ices of methanol (CH 3 OH) and acetaldehyde (CH 3 CHO) analogous to interstellar ices in the ISM exposed to ionizing radiation at ultralow temperatures of 5 K. Exploiting photoionization reflectron time-of-flight mass spectrometry (PI-ReToF-MS) and isotopically labeled ices, the reaction products were selectively photoionized allowing for isomer discrimination during the temperature-programmed desorption phase. Based on the distinct mass-to-charge ratios and ionization energies of the identified species, we reveal the formation pathways of hydroxyacetone (CH 3 COCH 2 OH), methyl acetate (CH 3 COOCH 3 ), and 3-hydroxypropanal (HCOCH 2 CH 2 OH) via radical–radical recombination reactions and of their enol tautomers (prop-1-ene-1,2-diol (CH 3 C(OH)CHOH), prop-2-ene-1,2-diol (CH 2 C(OH)CH 2 OH), 1-methoxyethen-1-ol (CH 3 OC(OH)CH 2 ) and prop-1-ene-1,3-diol (HOCH 2 CHCHOH)) via keto-enol tautomerization. To the best of our knowledge, 1-methoxyethen-1-ol (CH 3 OC(OH)CH 2 ) and prop-1-ene-1,3-diol (HOCH 2 CHCHOH) are experimentally identified for the first time. Our findings help to constrain the formation mechanism of hydroxyacetone and methyl acetate detected within star-forming regions and suggest that the hitherto astronomically unobserved isomer 3-hydroxypropanal and its enol tautomers represent promising candidates for future astronomical searches. These enol tautomers may contribute to the molecular synthesis of biologically relevant molecules in deep space due to their nucleophilic character and high reactivity. 

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2. A nuclear physics example of statistical bootstrap is used on the MARATHON nucleon structure function ratio data in the quark momentum fraction regions xB → 0 and xB → 1. The extrapolated F2 ratio as quark momentum fraction xB → 1 is Fn 2 F p 2 → 0.4 ± 0.05 and this value is compared to theoretical predictions. The extrapolated ratio when xB → 0 favors the simple model of isospin symmetry with the complete dominance of sea quarks at low momentum fraction. At high-xB, the proton quark distribution function ratio d/u is derived from the F2 ratio and found to be d/u → 1/6. Our extrapolated values for both the Fn 2 F p 2 ratio and the d/u parton distribution function ratio are within uncertainties of perturbative QCD values from quark counting, helicity conservation arguments, and a Dyson-Schwinger equation with a contact interaction model. In addition, it is possible to match the statistical bootstrap value to theoretical predictions by allowing two compatible models to act simultaneously in the nucleon wave function. One such example is nucleon wave functions composed of a linear combination of a quark-diquark state and a three-valence quark correlated state with coefficients that combine to give the extrapolated F2 ratio at xB = 1.

   https://doi.org/10.1103/PhysRevC.107.065203  

   Valenty, Hannah ; West, Jennifer Rittenhouse ; Benmokhtar, Fatiha ; Higinbotham, Douglas W. ; Parker, Asia ; Seroka, Erin ( June 2023 , Physical Review C)

   A nuclear physics example of statistical bootstrap is used on the MARATHON nucleon structure function ratio data in the quark momentum fraction regions xB → 0 and xB → 1. The extrapolated F2 ratio as quark momentum fraction xB → 1 is Fn 2 F p 2 → 0.4 ± 0.05 and this value is compared to theoretical predictions. The extrapolated ratio when xB → 0 favors the simple model of isospin symmetry with the complete dominance of sea quarks at low momentum fraction. At high-xB, the proton quark distribution function ratio d/u is derived from the F2 ratio and found to be d/u → 1/6. Our extrapolated values for both the Fn 2 F p 2 ratio and the d/u parton distribution function ratio are within uncertainties of perturbative QCD values from quark counting, helicity conservation arguments, and a Dyson-Schwinger equation with a contact interaction model. In addition, it is possible to match the statistical bootstrap value to theoretical predictions by allowing two compatible models to act simultaneously in the nucleon wave function. One such example is nucleon wave functions composed of a linear combination of a quark-diquark state and a three-valence quark correlated state with coefficients that combine to give the extrapolated F2 ratio at xB = 1. 

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3. Local structure, pseudosymmetry, and phase transitions in Na 1/2 Bi 1/2 TiO 3 –K 1/2 Bi 1/2 TiO 3 ceramics

   https://doi.org/10.1103/PhysRevB.87.024113  

   Levin, I. ; Reaney, I. M. ; Anton, E-M. ; Jo, Wook ; Rödel, J. ; Pokorny, J. ; Schmitt, L. A. ; Kleebe, H-J. ; Hinterstein, M. ; Jones, J. L. ( January 2013 , Physical Review B)
4. Gapped and gapless short-range-ordered magnetic states with (12,12,12) wave vectors in the pyrochlore magnet Tb2+xTi2−xO7+δ

   https://doi.org/10.1103/PhysRevB.92.245114  

   Kermarrec, E. ; Maharaj, D. D. ; Gaudet, J. ; Fritsch, K. ; Pomaranski, D. ; Kycia, J. B. ; Qiu, Y. ; Copley, J. R. ; Couchman, M. M. ; Morningstar, A. O. ; et al ( December 2015 , Physical Review B)
5. Gas-Phase Preparation of 1-Germavinylidene (H 2 CGe; X 1 A 1 ), the Isovalent Counterpart of Vinylidene (H 2 CC; X 1 A 1 ), via Non-adiabatic Dynamics through the Elementary Reaction of Ground State Atomic Carbon (C; 3 P) with Germane (GeH 4 ; X 1 A 1 )

   https://doi.org/10.1021/acs.jpclett.2c03749  

   Yang, Zhenghai ; Sun, Bing-Jian ; He, Chao ; Li, Jin-Qi ; Chang, Agnes H. ; Kaiser, Ralf I. ( January 2023 , The Journal of Physical Chemistry Letters)