scholarly journals Algae colonisation of brick pavement at the University of Venda: A potential slippery hazard

2019 ◽  
Vol 11 (2) ◽  
Author(s):  
Thabelo R. Munyai ◽  
Thandi Sonqishe ◽  
Jabulani R. Gumbo
Keyword(s):  
Green Algae ◽  
Inductively Coupled Plasma ◽  
Limpopo Province ◽  
Inductively Coupled ◽  
High Solar Radiation ◽  
Icp Ms ◽  
Metal Contents ◽  
Plasma Mass Spectrometry ◽  
Cyanobacteria And Algae ◽  
The University

A brick pavement, tramped by humans, is exposed to atmospheric elements, thus allowing cyanobacteria and algae to colonise. In this article, we report on the factors that contribute to the slipperiness of a brick pavement at the University of Venda in the Limpopo province of the South Africa. Samples were collected from brick surfaces either colonised by green algae (treated) or not (control). The samples were acid-digested and analysed for metals by Inductively Coupled Plasma Mass Spectrometry (ICP MS) in parts per billion (ppb). The treated bricks, with green algae, had average high metal contents (ppb): Al 9456.02, Ti 731.23, V 46.44, Cr 78.85, Mn 862.93, Fe 16295.18, Co 23.57, Ni 59.36, Cu 66.31, Zn 160.57, As 7.92, Se 10.45, Mo 6.74, Cd 5.19, Sn 4.65, Sb 2.31 and Pb 19.51. In contrast, control bricks had a low average of metal content (ppb) as follows: Al 2.99, Ti 0.28, V 4.04, Cr 1.42, Mn 4.29, Fe 20.89, Co 0.36, Ni 2.74, Cu 5.64, Zn 4.21, As 0.56, Se <3.00, Mo 0.88, Cd 0.01, Sn 1.05, Sb 0.04 and Pb 0.04. Other factors that promote algae colonisation include high solar radiation, neutral pH, nutrients, low electrical conductivity and total dissolved solids. The algae colonisation of brick pavement results in an unaesthetic sighting and a slippery surface that is hazardous to humans.

The hydrothermal Waterberg platinum deposit, Mookgophong (Naboomspruit), South Africa. Part II: Quartz chemistry, fluid inclusions and geochronology

2018 ◽  
Vol 82 (3) ◽  
pp. 751-778 ◽  
Author(s):  
Alfons M. van den Kerkhof ◽  
Graciela M. Sosa ◽  
Thomas Oberthür ◽  
Frank Melcher ◽  
Tobias Fusswinkel ◽  
...  
Keyword(s):  
South Africa ◽  
Inductively Coupled Plasma ◽  
Age Determination ◽  
Hydrothermal Activity ◽  
Limpopo Province ◽  
Chloride Complexes ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Platinum Group

AbstractThe historic Waterberg platinum deposit, ~15 km WNW of Mookgophong (formerly Naboomspruit), Limpopo Province, South Africa, is a rare fault-bound hydrothermal vein-type quartz-hematite-platinum-group mineralization. As a continuation of the geochemistry and ore mineralogy studies (Part I, Oberthür et al., 2018), this paper concentrates on the ore-bearing quartz and on the age constraints of ore formation. The state-of-the-art methods used include cathodoluminescence microscopy, electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of trace elements, stable isotope (δ18O) analysis and fluid-inclusion studies. U-Pb and (U-Th)/He radiometric age determination gave ages of 900–1075 Ma suggesting platinum-group element (PGE) mineralization as a result of upwelling fluids with connection to the Bushveld complex during Kibaran tectonic movements along the Thabazimbi–Murchison Lineament. Felsic fragments containing Qtz-1 were cemented by different quartz generations (Qtz-2 to Qtz-4) and enable the characterization of the changing physicochemical parameters during multistage mineralization and cooling. The PGE minerals are associated with the earliest hydrothermal stage represented by botryoidal radial-fibrous quartz aggregates (Qtz-2a) which formed on brecciated felsite. The other quartz types are essentially barren. Cathodoluminescence studies of quartz indicate very high Al, Fe and K concentrations as confirmed by EPMA and LA-ICP-MS, whereas Ti is always very low. The varying Al concentrations in the quartz mainly indicate pH fluctuations, the high Fe3+ points at high oxygen fugacity. Micro-inclusions of iron oxide are associated with Pt ore (Fe, Pt, Pd, Au, W, Sb, As), rutile, kaolinite and muscovite. The hydrothermal activity must have been characterized by low saline (<10 wt%) H2O–NaCl solutions. These fluids mixed with original high-saline NaCl ± CaCl2 ± CO2 brines in the brecciated felsite (Qtz-1). According to the quartz-hematite geothermometer the ore depositional temperatures were ~370–330°C (Qtz-2a), whereas the successive quartz veins formed during cooling towards ~295°C. The transport of PGE must have been facilitated by strongly oxidizing chloride complexes of relatively low salinity and moderate acidity.

Interlaboratory variability of urinary iodine measurements

2018 ◽  
Vol 56 (3) ◽  
pp. 441-447 ◽  
Author(s):  
Till Ittermann ◽  
Simone Johner ◽  
Harald Below ◽  
Matthias Leiterer ◽  
Michael Thamm ◽  
...  
Keyword(s):  
Gold Standard ◽  
Inductively Coupled Plasma ◽  
Urinary Iodine ◽  
Population Based ◽  
Inductively Coupled ◽  
University Medicine ◽  
Interlaboratory Variability ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
The University

AbstractBackground:The iodine status of populations is usually assessed by median urinary iodine concentrations (UIC) in population-based studies, but it is unclear to which extent UIC are comparable across different laboratories. The aim of our study was to investigate the variability of UIC measurements across three well-established German laboratories with long-term clinical-chemical expertise in iodine measurements and to compare these results to the gold standard inductively coupled plasma mass spectrometry (ICP-MS).Methods:UIC levels were measured from 303 urine samples derived from the “Dortmund Nutritional and Anthropometric Longitudinally Designed Study” and from volunteers of the University Medicine Greifswald at four different German laboratories. Three of these laboratories used Sandell-Kolthoff reaction with different digestion methods for UIC measurement (Lab1–Lab3), whereas one laboratory used ICP-MS as gold standard.Results:Median UIC levels were significantly different across the four laboratories (ICP-MS: 77 μg/L; Lab1: 69 μg/L; Lab2: 73 μg/L; Lab3: 111 μg/L). Linear regressions associating UIC levels of Lab1–Lab3 with UIC levels of ICP-MS showed intercepts significantly different from 0 and slopes significantly different from 1. Intraclass correlations (ICC) in comparison to ICP-MS were 0.91 for Lab1, 0.98 for Lab2, and 0.69 for Lab3. Using the digestion method of Lab2 in Lab3 improved the comparison of UIC levels of Lab3 with those from the ICP-MS (ICC=0.89).Conclusions:We have demonstrated larger interlaboratory variations across high-quality laboratories with long-lasting experience in iodine measurements indicating a relevant non-comparability of UIC measurements in iodine monitoring studies. Therefore, standardization of UIC measurements has to be expedited.

SOL-ENHANCED Au–Ni–TiO2 ELECTROPLATED COATINGS

2013 ◽  
Vol 27 (19) ◽  
pp. 1341010 ◽  
Author(s):  
YING JU ◽  
YUXIN WANG ◽  
WEI GAO
Keyword(s):  
Titanium Dioxide ◽  
Inductively Coupled Plasma ◽  
Scale Up ◽  
Processing Parameters ◽  
Thickness Variation ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Electroplating Process ◽  
The University

A sol-enhanced gold ( Au ) — nickel ( Ni ) — titanium dioxide ( TiO 2) composite coating technique has been developed at the University of Auckland. The aim of the present study is to achieve quality control and thickness homogeneity of the coatings in order to scale up this process to the workshop level. Multi-coating samples were prepared in the same electroplating unit with same processing parameters. The thickness variation and influence of titanium dioxide ( TiO 2) sol content on the thickness have been studied. The consumption of Au and Ti ions in the electrolytes during the electroplating process was measured by inductively coupled plasma-mass spectrometry (ICP–MS) method. The cross-section microstructures of coatings were studied by field emission scanning electron microscope (FESEM) with an energy dispersive spectroscopy (EDS) system. An optimized processing method has been put forward for the industry process to produce coatings with uniform thickness and good quality.

scholarly journals Early Paleozoic zircon ages of the Higher Himalayan Gneisses of the Everest region and their Pan-African/Proto-Himalayan orogenic signature

2019 ◽  
Vol 59 ◽  
pp. 107-124 ◽  
Author(s):  
Masaru Yoshida ◽  
George E. Gehrels ◽  
Bishal N. Upreti ◽  
Santa M. Rai
Keyword(s):  
Inductively Coupled Plasma ◽  
Inductively Coupled ◽  
Pan African ◽  
Icp Ms ◽  
University Of Arizona ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
High Grade Metamorphism ◽  
Almost All ◽  
The University

The U-Pb analysis of zircons from two independent leucosome bodies belonging to the paragneiss of the Higher Himalayan Crystallines Sequence (HHCS) in the Everest region of eastern Nepal Himalaya was carried out using laser ablation-multi collector inductively coupled plasma-mass spectrometry (LA-MC-ICP-MS) at the University of Arizona, Tucson, USA. The analysis of zircons from sample 07EVT3 forms a discordia with upper and lower intercepts at 478±25 and 21.5±4.1 Ma with concordant ages of 488.5±9.2 and 20.9±0.9 Ma for cores and rims, respectively. Similarly, the analysis of zircons from sample U1206 forms a discordia with upper and lower intercepts at 515±20 and 34.8±2.7 Ma, and provides concordant ages of 463.9±10.9 and 24.6±0.6 Ma for cores and rims, respectively. No inherited zircon grains with older ages were found indicating that almost all these zircons must have formed along with the leucotomies during the ca. 500 Ma metamorphism of the protoliths. The high U/Th ratio, i.e. average 11.0 for zircons from sample 07EVT3 and 253.6 for sample U1206 also support a metamorphic origin of the zircons. The occurrences of zircons in the ca. 500Ma leucosomes in the HHCS strongly points that rocks in the Himalayan area had undergone to a high-grade metamorphism during the late Pan-African time. We call this metamorphism as the Proto himalayan metamorphism. More studies along this line will help to better understand and constrain the Pan-African orogenic history of the Proto-Himalayan Orogen within the Peri-Gondwana Orogenicterrains.

Single Particle Inductively Coupled Plasma Mass Spectrometry: Investigating Nonlinear Response Observed in Pulse Counting Mode and Extending the Linear Dynamic Range by Compensating for Dead Time Related Count Losses on a Microsecond Timescale

2019 ◽  
Author(s):  
Ingo Strenge ◽  
Carsten Engelhard
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Nonlinear Response ◽  
Dynamic Range ◽  
Dead Time ◽  
Inorganic Nanoparticles ◽  
Linear Dynamic Range ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry

<p>The article demonstrates the importance of using a suitable approach to compensate for dead time relate count losses (a certain measurement artefact) whenever short, but potentially strong transient signals are to be analysed using inductively coupled plasma mass spectrometry (ICP-MS). Findings strongly support the theory that inadequate time resolution, and therefore insufficient compensation for these count losses, is one of the main reasons for size underestimation observed when analysing inorganic nanoparticles using ICP-MS, a topic still controversially discussed.</p>

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