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1. A vacuum ultraviolet photoionization study on the formation of methanimine (CH 2 NH) and ethylenediamine (NH 2 CH 2 CH 2 NH 2 ) in low temperature interstellar model ices exposed to ionizing radiation

   https://doi.org/10.1039/c8cp06002a  

   Zhu, Cheng ; Frigge, Robert ; Turner, Andrew M. ; Abplanalp, Matthew J. ; Sun, Bing-Jian ; Chen, Yue-Lin ; Chang, Agnes H. ; Kaiser, Ralf I. ( January 2019 , Physical Chemistry Chemical Physics)

   Methylamine (CH 3 NH 2 ) and methanimine (CH 2 NH) represent essential building blocks in the formation of amino acids in interstellar and cometary ices. In our study, by exploiting isomer selective detection of the reaction products via photoionization coupled with reflectron time of flight mass spectrometry (Re-TOF-MS), we elucidate the formation of methanimine and ethylenediamine (NH 2 CH 2 CH 2 NH 2 ) in methylamine ices exposed to energetic electrons as a proxy for secondary electrons generated by energetic cosmic rays penetrating interstellar and cometary ices. Interestingly, the two products methanimine and ethylenediamine are isoelectronic to formaldehyde (H 2 CO) and ethylene glycol (HOCH 2 CH 2 OH), respectively. Their formation has been confirmed in interstellar ice analogs consisting of methanol (CH 3 OH) which is ioselectronic to methylamine. Both oxygen-bearing species formed in methanol have been detected in the interstellar medium (ISM), while for methanimine and ethylenediamine only methanimine has been identified so far. In comparison with the methanol ice products and our experimental findings, we predict that ethylenediamine should be detectable in these astronomical sources, where methylamine and methanimine are present. 

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2. Intermediate Sr 2 Co 1.5 Fe 0.5 O 6−δ Tetragonal Structure between Perovskite and Brownmillerite as a Model Catalyst with Layered Oxygen Deficiency for Enhanced Electrochemical Water Oxidation

   https://doi.org/10.1021/acscatal.1c00465  

   Ede, Sivasankara Rao ; Collins, Candyce N. ; Posada, Carlos D. ; George, Gibin ; Wu, Hui ; Ratcliff, William D. ; Lin, Yulin ; Wen, Jianguo ; Han, Shubo ; Luo, Zhiping ( April 2021 , ACS Catalysis)

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3. A Bidirectional Subsurface Remote Sensing Reflectance Model Explicitly Accounting for Particle Backscattering Shapes: BIDIRECTIONAL rrs MODEL

   https://doi.org/10.1002/2017JC013313  

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4. A Simple Condensation Model for the H 2 SO 4 ‐H 2 O Gas‐Cloud System on Venus

   https://doi.org/10.1029/2021JE007060  

   Dai, Longkang ; Zhang, Xi ; Shao, Wencheng D. ; Bierson, Carver J. ; Cui, Jun ( February 2022 , Journal of Geophysical Research: Planets)

   The current Venus climate is largely regulated by globally covered concentrated sulfuric acid clouds from binary condensation of sulfuric acid (H₂SO₄) and water (H₂O). To understand this complicated H₂SO₄‐H₂O gas‐cloud system, previous theoretical studies either adopted complicated microphysical calculations or assumed that both H₂SO₄and H₂O vapor follow their saturation vapor pressure. In this study, we developed a simple one‐dimensional cloud condensation model including condensation, diffusion and sedimentation of H₂SO₄and H₂O but without detailed microphysics. Our model is able to explain the observed vertical structure of cloud and upper haze mass loading, cloud acidity, H₂SO₄, and H₂O vapor, and the mode‐2 particle size on Venus. We found that most H₂SO₄is stored in the condensed phase above 48 km, while the partitioning of H₂O between the vapor and clouds is complicated. The cloud cycle is mostly driven by evaporation and condensation of H₂SO₄rather than H₂O and is about seven times stronger than the H₂SO₄photochemical cycle. Most of the condensed H₂O in the upper clouds is evaporated before the falling particles reach the middle clouds. The cloud acidity is affected by the temperature and the condensation‐evaporation cycles of both H₂SO₄and H₂O. Because of the large chemical production of H₂SO₄vapor and relatively inefficient cloud condensation, the simulated H₂SO₄vapor above 60 km is largely supersaturated by more than two orders of magnitude, which could be tested by future observations.

    

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5. Erratum: “Energy of the quasi-free electron in H 2 , D 2 , and O 2 : Probing intermolecular potentials within the local Wigner-Seitz model” [J. Chem. Phys. 143, 224303 (2015)]

   https://doi.org/10.1063/1.4942490  

   Evans, C. M. ; Krynski, Kamil ; Streeter, Zachary ; Findley, G. L. ( March 2016 , The Journal of Chemical Physics)