Results 51 to 60 of about 740,577 (309)

CHEMISTRY OF ANTARCTIC SNOW AND ICE [PDF]

Le Journal de Physique Colloques, 1987
We have studied 1000 samples of snow and ice from East and West Antarctica (coastal as well as central areas). These samples cover different time periods up to 30,000 years B.P.. In the meltwater, we have measured major ions (i.e. Na+, NH4+, K+, Ca++, Mg++, H+, Cl-, NO3-, and SO4--) using stringent contamination free tehniques.
openaire   +1 more source

The contribution of wood burning and other pollution sources to wintertime organic aerosol levels in two Greek cities [PDF]

Atmospheric Chemistry and Physics, 2017
The composition of fine particulate matter (PM) in two major Greek cities (Athens and Patras) was measured during two wintertime campaigns, one conducted in 2013 and the other in 2012.
K. Florou, D. K. Papanastasiou, M. Pikridas, C. Kaltsonoudis, E. Louvaris, G. I. Gkatzelis, D. Patoulias, N. Mihalopoulos, S. N. Pandis   +8 more
doaj   +1 more source

Technical Note: VUV photodesorption rates from water ice in the 120-150 K temperature range - significance for Noctilucent Clouds [PDF]

, 2010
Laboratory studies have been carried out with the aim to improve our understanding of physicochemical processes which take place at the water ice/air interface initiated by solar irradiation with a wavelength of 121.6 nm.
Bluszcz, Thaddäus, Feigin, A. M., Ignatov, Stanislav, Kulikov, Mikhail, Schrems, Otto, Sennikov, Peter   +5 more
core   +1 more source

Microbial and Geochemical Evidence of Permafrost Formation at Mamontova Gora and Syrdakh, Central Yakutia

Frontiers in Earth Science, 2021
Biotracers marking the geologic history and permafrost evolution in Central Yakutia, including Yedoma Ice Complex (IC) deposits, were identified in a multiproxy analysis of water chemistry, isotopic signatures, and microbial datasets.
M. Yu. Cherbunina, E. S. Karaevskaya, Yu. K. Vasil’chuk, N. I. Tananaev, D. G. Shmelev, N. A. Budantseva, A. Y. Merkel, A. L. Rakitin, A. V. Mardanov, A. V. Brouchkov, S. A. Bulat, S. A. Bulat   +11 more
doaj   +1 more source

The Dominion Range Ice Core, Queen Maud Mountains, Antarctica - General Site and Core Characteristics with Implications [PDF]

, 2017
The Transantarctic Mountains of East Antarctica provide a new milieu for retrieval of ice-core records. We report here on the initial findings from the first of these records, the Dominion Range ice-core record.
Gow, Anthony J., Grootes, Pieter M., Lyons, W. Berry, Mayewski, Paul A., Meese, Debra A., Saltzman, Eric, Sowers, Todd, Spencer, Mary Jo, Twickler, Mark S., Watson, M. Scott   +9 more
core   +1 more source

Chemical fractionation of deuterium in the protosolar nebula

, 2017
Understanding gas-grain chemistry of deuterium in star-forming objects may help to explain their history and present state. We aim to clarify how processes in ices affect the deuterium fractionation.
Hocuk, S., Kalnin, J. R., Kalvans, J., Shmeld, I.   +3 more
core   +1 more source

Wet scavenging of soluble gases in DC3 deep convective storms using WRF-Chem simulations and aircraft observations [PDF]

, 2016
We examine wet scavenging of soluble trace gases in storms observed during the Deep Convective Clouds and Chemistry (DC3) field campaign. We conduct high-resolution simulations with the Weather Research and Forecasting model with Chemistry (WRF-Chem) of ...
Allen, Dale J, Apel, Eric C, Barth, Mary C, Bela, Megan M, Blake, Donald R, Blake, Nicola J, Campos, Teresa, Chen, Dexian, Crounse, John D, Cummings, Kristin A, Diskin, Glenn, Flocke, Frank, Fried, Alan, Homeyer, Cameron R, Hornbrook, Rebecca S, Huey, L Gregory, Li, Yunyao, Liu, Xiaoxi, Morrison, Hugh, O'Sullivan, Daniel, Pickering, Kenneth E, St Clair, Jason M, Teng, Alex P, Toon, Owen B, Wennberg, Paul O, Yang, Qing   +25 more
core   +2 more sources

Sequence determinants of RNA G‐quadruplex unfolding by Arg‐rich regions

FEBS Letters, EarlyView.
We show that Arg‐rich peptides selectively unfold RNA G‐quadruplexes, but not RNA stem‐loops or DNA/RNA duplexes. This length‐dependent activity is inhibited by acidic residues and is conserved among SR and SR‐related proteins (SRSF1, SRSF3, SRSF9, U1‐70K, and U2AF1).
Naiduwadura Ivon Upekala De Silva, Puspa Kunwar, Md Ibnul Rifat Rahman, Joanna Koryo Kwao, Nathan Lehman, Zihan Zhang, Trenton Paul, Claire Cheng, Nicholas Truex, Hui‐Ting Lee, Jun Zhang   +10 more
wiley   +1 more source

The cometary composition of a protoplanetary disk as revealed by complex cyanides

, 2015
Observations of comets and asteroids show that the Solar Nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth's surface, seeding its early chemistry.
A Dutrey, A Dutrey, C Brinch, C Favre, C Qi, C Qi, C Qi, C Walsh, C Walsh, C Walsh, C Walsh, Chunhua Qi, D Lynden-Bell, D Semenov, David J. Wilner, DM Graninger, DP O’Brien, E Bergin, E Dartois, E Herbst, EC Fayolle, EF van Dishoeck, EF van Dishoeck, EI Chiang, FJ Ciesla, GM Muñoz Caro, H Nomura, JS Carr, K Furuya, K Tsiganis, KA Rosenfeld, Karin I. Öberg, Kenji Furuya, KI Öberg, KI Öberg, KI Öberg, KJ Walsh, KM Pontoppidan, L Hartmann, LI Cleeves, LI Cleeves, M Dubernet, M Simon, M Takami, M Wernli, MJ Mumma, MP Collings, MR Hogerheijde, N Goldman, N Sakai, P D'Alessio, P Gratier, P Hartogh, RT Garrod, Ryan Loomis, S Guilloteau, S Pizzarello, Sean M. Andrews, T Yamamoto, V Piétu, V Wakelam, Viviana V. Guzmán, Y Aikawa, Y Aikawa, Yuri Aikawa   +64 more
core   +1 more source

Structural instability impairs function of the UDP‐xylose synthase 1 Ile181Asn variant associated with short‐stature genetic syndrome in humans

FEBS Letters, EarlyView.
The Ile181Asn variant of human UDP‐xylose synthase (hUXS1), associated with a short‐stature genetic syndrome, has previously been reported as inactive. Our findings demonstrate that Ile181Asn‐hUXS1 retains catalytic activity similar to the wild‐type but exhibits reduced stability, a looser oligomeric state, and an increased tendency to precipitate ...
Tuo Li, Pedro A. Sánchez‐Murcia, Bernd Nidetzky   +2 more
wiley   +1 more source