Characterization of atmospheric 210Pb concentration and its relation to major ion species at Tsukuba, Japan

Author(s):  
Naofumi Akata ◽  
Chie Iwata ◽  
Miki Nakada ◽  
Masahiro Tanaka ◽  
Hideki Kakiuchi ◽  
...  
1989 ◽  
Vol 94 (A4) ◽  
pp. 3579 ◽  
Author(s):  
L. M. Kistler ◽  
F. M. Ipavich ◽  
D. C. Hamilton ◽  
G. Gloeckler ◽  
B. Wilken ◽  
...  

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2587
Author(s):  
Jessica McKay ◽  
Melissa Lenczewski ◽  
Rosa Maria Leal-Bautista

The Yalahau region, located in the northeastern portion of the Yucatán Peninsula, hosts a series of elongated depressions trending north/south in the direction of Isla Holbox, identified as the Holbox Fracture Zone. Previous studies have explored the geomorphology and various hydrologic characteristics of the Yucatán Peninsula; however, there is a paucity of data concerning the interior region where the fractures are located. Strontium isotope ratios and major ion geochemistry data of the surface water and groundwater of this region serve as a hydrogeochemical fingerprint, aiding in constraining the hydrological boundaries, determining flow paths, and characterizing hydrogeochemical processes that impact the composition of the groundwater within the region. 87Sr/86Sr isotope ratios indicate a different signature than the surrounding bedrock Sr ratio, suggesting that the flow throughout the Yalahau region is moving through channels faster than that of much of the Yucatán. Through major ion geochemistry and 87Sr/86Sr isotope ratios, we were able to delineate at least two flow paths within the Yalahau region and identify a point of saline intrusion at least 35 km from the coast. Gaining an understanding of the hydrogeochemistry and water flow regions is crucial in determining the impact of various activities (e.g., extensive tourism, drinking water withdrawal, wastewater discharge/injection) that occur within the Yucatán Peninsula.


2004 ◽  
Vol 75 (5) ◽  
pp. 1822-1825 ◽  
Author(s):  
A. A. Ivanov ◽  
P. P. Deichuli ◽  
A. Kreter ◽  
V. V. Maximov ◽  
B. Schweer ◽  
...  

Author(s):  
Eva I. Preiß ◽  
Benoit Merle ◽  
Yuan Xiao ◽  
Florentina Gannott ◽  
Jan P. Liebig ◽  
...  

Abstract Focused ion beam (FIB) milling is an increasingly popular technique for fabricating micro-sized samples for nanomechanical characterization. Previous investigations have cautioned that exposure to a gallium ion beam can significantly alter the mechanical behavior of materials. In the present study, the effects of gallium, neon, and xenon ions are scrutinized. We demonstrate that fracture toughness measurements on freestanding gold thin films are unaffected by the choice of the ion species and milling parameters. This is likely because the crack initiation is controlled by the local microstructure and grain boundaries at the notch, rather than by the damaged area introduced by FIB milling. Additionally, gold is not susceptible to chemical embrittlement by common FIB ion species. This confirms the validity of microscale fracture measurements based on similar experimental designs. Graphical abstract


2020 ◽  
Vol 129 (1) ◽  
Author(s):  
Tirumalesh Keesari ◽  
Anndasankar Roy ◽  
Diksha Pant ◽  
Uday Kumar Sinha ◽  
P V Nagendra Kumar ◽  
...  

2016 ◽  
Vol 35 (1) ◽  
pp. 72-80 ◽  
Author(s):  
M. Cutroneo ◽  
A. Mackova ◽  
L. Torrisi ◽  
V. Lavrentiev

AbstractThis work reports a comparative study of laser ion implantation mainly performed at the Nuclear Physics Institute in Rez (Czech Republic), National Institute of Nuclear Physics (Italy), and the Plasma Physics Laboratory at the University of Messina (Italy) using different approaches. Thick metallic targets were irradiated in vacuum by a focused laser beam to generate plasma-producing multi-energy and multi-species ions. A post-acceleration system was employed in order to increase the energy of the produced ions and to generate ion beams suitable to be implanted in different substrates. The ion dose was controlled by the laser repetition rate and the time of irradiation. Rutherford backscattering analysis was carried out to evaluate the integral amount of implanted ion species, the concentration–depth profiles, the ion penetration depth, and the uniformity of depth profiles for ions laser implanted into monocrystalline substrates. The laser implantation under normal conditions and in post-acceleration configuration will be discussed on the basis of the characterization of the implanted substrates.


2006 ◽  
Vol 43 ◽  
pp. 230-238 ◽  
Author(s):  
Kaplan Yalcin ◽  
Cameron P. Wake ◽  
Shichang Kang ◽  
Karl J. Kreutz ◽  
Sallie I. Whitlow

AbstractSamples collected from four snow pits at Eclipse Icefield, Yukon, Canada, were analyzed for stable isotopes and major ions to assess seasonal and spatial variability in snow chemistry. Accumulation since the end of the 2001 summer season over the 0.1 km2 area sampled ranges from 0.77 to 1.16mw.e. Snow-pit stratigraphy and chemical records demonstrate that the low accumulation at pit 3 is due to an under-representation of winter snow accumulation at that site. For all major-ion species, chemical concentrations are independent of snow accumulation rate. Seasonal variations are evident in the major-ion records and can be divided between sea-salt species (Na+, Cl−) that peak in late fall to winter, and dust (Ca2+, Mg2+, K+) and other species (NH4+, NO3−, SO42–, C2O22–) that peak in late spring to summer. The signal common to all four snow pits identified by empirical orthogonal function analysis ranges from 49% of the total variance for Na+ and Cl− to as high as 80% of the total variance for SO42–. There is greater spatial variability in species associated with coarse-mode particles (Na+, Cl−, Ca2+, Mg2+) than in species present mainly in accumulation-mode aerosols (SO42–, NH4+) or in the gas phase (NO3−).


2006 ◽  
Vol 252 (19) ◽  
pp. 6742-6745 ◽  
Author(s):  
S. Hellweg ◽  
A. Jacob ◽  
J.D. Hoheisel ◽  
T. Grehl ◽  
H.F. Arlinghaus

Sign in / Sign up

Export Citation Format

Share Document