scholarly journals A Multifaceted Approach for Determining Sediment Provenance to Coastal Shipping Channels

2019 ◽  
Vol 7 (12) ◽  
pp. 434
Author(s):  
Emma L. Jackson ◽  
Nathan B. English ◽  
Andrew D. Irving ◽  
Andrew M. Symonds ◽  
Gordon Dwane ◽  
...  
Keyword(s):  
Rare Earth ◽  
Management Strategies ◽  
Isotope Analysis ◽  
Particle Size Analysis ◽  
Sediment Provenance ◽  
Size Analysis ◽  
Sediment Sources ◽  
Wet Season ◽  
Sediment Samples ◽  
Longshore Drift

Maintenance dredging for shipping channels is required to maintain safe and efficient navigational channels and berths in ports around the world. Sediment that refills dredged channels can enter ports via alluvial transport of eroded materials from upstream and adjacent catchments, from marine transport due to tidal currents and wind driven currents and from longshore drift. Identifying the provenance of sediment infilling navigational channels allows port operators to mitigate and manage sediment transport, potentially reducing dredging requirements and costs. Further, understanding sediment sources can inform options for beneficial reuse or disposal of dredged sediments. A multi-faceted approach was used to assess whether sediment provenance in the Port of Gladstone could be characterized. A combination of particle size analysis, rare earth element composition, carbon stable isotope ratios, strontium isotopes, and beryllium-7 radioisotopes was employed. Samples were collected at accumulation locations within the navigational channel. Potential sediment sources were sampled from sites of longshore drift to the south of the Port of Gladstone, and intertidal sand and mud representative of transport from currents. Fluvial sediment samples were collected during dry and wet season conditions and from the three main local catchments. Potential source sediment samples yielded identifiable differences with respect to rare earth elements, while beryllium-7 isotope analysis indicated recent deposition of sediments from mudflats or catchment within the channels. The approach used here provided insights into the source of recently deposited sediments to the dredged channels, enabling managers to make informed decisions on mitigation and management strategies.

Sediments of the Wala catchment and reservoir, Jordan: Geochemical analysis

2020 ◽  
Author(s):  
Esraa Tarawneh ◽  
Jonathan Bridge ◽  
Neil Macdonald
Keyword(s):  
Discrete Event ◽  
Ground Truth ◽  
Particle Size Analysis ◽  
Health Concern ◽  
Sediment Provenance ◽  
Size Analysis ◽  
Geochemical Analysis ◽  
Aquifer Recharge ◽  
Bed Sediments ◽  
The North

<p>This study reports data from field sampling of catchment and reservoir bed sediments undertaken in October 2013 in the Wala catchment, Jordan, and findings of geochemical analysis of the sediments. The primary aim of this study is to investigate the relationship between sediments from different locations within the catchment and those deposited within the reservoir. This is set within the overall context of an attempt to rationalise the use of modelling in a data-poor environment. Can targeted, limited acquisition of geochemical information within a logistically challenging environment add value to existing datasets in respect of ground truth for model predictions of sediment provenance within the catchment? Channel bed sediments were collected from sub-catchment outlets throughout the Wala catchment and shallow cores (c. 500 mm) extracted from three locations around the Wala reservoir. XRF and particle size analysis were performed on all samples and the data analysed in respect of mineralogical and pollutant geochemical signatures. Contrary to evidence from temperate lake studies, there was no strong record of discrete event-driven deposition at the Wala, likely due to reworking of sediments during high-flow recharge events following complete draw-down of the reservoir in the highly intermittent hydrological setting. Pollutant geochemistry shows variations consistent with patterns of land-use in the catchment, with levels of Pb, Co, Cu and Cr associated with urbanised regions in the north and west of the region. Sampled concentrations, particularly those of the reservoir sediments, are typically below thresholds for environmental health concern. However, combined with the modelled bias in flow and sediment inputs from this region (driven by asymmetric rainfall distribution), this emphasises a potential concern for future management of water quality and protection of groundwater during aquifer recharge.</p>

scholarly journals Metals distribution and particle size analysis in water and sediment of the Djetinja river and Dragica spring (Serbia)

2010 ◽  
Vol 16 (4) ◽  
pp. 363-372 ◽  
Author(s):  
Jelena Kiurski ◽  
Milica Vucinic-Vasic ◽  
Snezana Aksentijevic ◽  
Uranija Kozmidis-Luburic ◽  
Mirjana Vojinovic-Miloradov
Keyword(s):  
Particle Size ◽  
River Basin ◽  
Size Range ◽  
Suspended Solid ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Sediment Samples ◽  
Water And Sediment ◽  
Zone Ii ◽  
First Time

This paper reports the results on total metal concentration (Al, Fe, Cr, Cu, Ni and Zn) in water and sediment of the Djetinja river basin in the area of western Serbia. Samples were collected in spring season. Based on the comparison of the concentrations of all analyzed metals it is possible to differentiate two zones: zone I (sampling sites 1-4), affected by the discharge of the Dragica spring, and zone II (sites 5-8), affected by the confluence of the Dragica spring with the Djetinja river. The analysis of suspended solid particle size in water as well as in sediment samples were performed in size range 0.02-2000 mm and a positive correlation was found with the concentration of aluminium, zinc, iron and nickel in water samples. The study of particle size and metals distribution through the river basin of the Djetinja was a useful tool for getting information about the distribution degree of the polluting agents, and their possible evolution growth and pollution sources. The research of metals distribution and particle size analysis in water and sediment of the Djetinja river and Dragica spring (Serbia) was conducted for the first time.

Mineralogy and chemistry of a new halloysite deposit from the Rio de Janeiro pegmatite province, south-eastern Brazil

Clay Minerals ◽  
2021 ◽  
pp. 1-15
Author(s):  
Victor Matheus Joaquim Salgado-Campos ◽  
Luiz Carlos Bertolino ◽  
Francisco José da Silva ◽  
Julio Cezar Mendes ◽  
Reiner Neumann
Keyword(s):  
Rare Earth ◽  
Inductively Coupled Plasma ◽  
Rio De Janeiro ◽  
Rietveld Method ◽  
Mineral Exploration ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Average Chemical Composition ◽  
Heavy Rare Earth Element ◽  
X Ray

Abstract Halloysite is a 1:1 dioctahedral clay mineral that has been studied widely for applications in nanotechnology and as a mineral exploration guide for recognizing regolith-hosted heavy rare earth element (HREE) deposits. In Brazil, pegmatites from the state of Rio de Janeiro have been catalogued, but their potential to host halloysite deposits has never been studied. After a mineral exploration programme, one pegmatite with considerable halloysite contents and economic potential was discovered. This study reports the mineralogical and chemical characterization of the halloysite of this pegmatite and evaluates the possibility of clay-adsorbed HREE deposits, like that in the Zudong (China) regolith-hosted HREE deposit. Seven samples were collected in horizontal channels. Bulk samples and clay fractions (<2 μm) were analysed by quantitative mineral analysis (X-ray diffraction/Rietveld method), chemical analysis (major elements by X-ray fluorescence and Y, U, Th and rare earth elements by inductively coupled plasma mass spectrometry), scanning electron microscopy, Fourier-transform infrared spectroscopy, particle-size analysis, nitrogen physisorption and cation-exchange capacity. Mixed polygonal/cylindrical halloysite-7Å in concentrations between 6.3 and 35.4 wt.% in bulk samples and between 58.0 and 89.8 wt.% in the clay fractions were identified in the pegmatite. The clay fractions presented an average chemical composition of 45.46 wt.% SiO2, 36.10 wt.% Al2O3, 14.62 wt.% loss on ignition and 1.04 wt.% Fe2O3, as well as technological properties close to those observed in world-class halloysite deposits such as Dragon Mine (USA) and Matauri Bay (New Zealand). The clay minerals did not present significant HREE contents.

scholarly journals Geochemical Pollution Assessment of Sediment Metal from Lower Region of the Ogun River, Nigeria

2014 ◽  
pp. 13-18
Author(s):  
Anslem Diayi ◽  
Michael Gbadebo
Keyword(s):  
Particle Size ◽  
Sediment Quality ◽  
Pollution Assessment ◽  
Particle Size Analysis ◽  
Index Formula ◽  
Size Analysis ◽  
Metal Concentrations ◽  
Lower Region ◽  
Sediment Samples ◽  
Ogun River

From depths of 0-5 cm, 5-10 cm and 10-15 cm, sediment samples were collected from three locations in the lower region of the Ogun River Basin, namely Mokoloki, Oke-Oko and Kara. The samples were obtained using Van Veen sediment grab after which they were stored in well labeled polythene bags for onward transportation to the laboratory. For pH and conductivity, samples were determined in-situ using standard methods by the American Public Health Association of 1992 while Organic Carbon was determined by the Wakley Method. The sediments were then air dried before analysis for particle size and metal concentration. Induced Couple Plasma Mass Spectrometry (ICP/MS) was used to determine metal concentrations. Data obtained were used to determine the geochemical pollution intensities for the various sediment samples. The results of physicochemical analyses revealed all sediment samples to be alkaline, while particle size analysis showed that the sediments were sandy. All metal concentrations for Cu, Pb, As, Zn, Hg, Cd, and Cr were lower than the Environment Canada Sediment Quality Guideline standards of 35.70 ppm, 35.00 ppm, 0.60 ppm, 123.00 ppm, 5.90 ppm, 0.17 ppm and 37.50 ppm, respectively. The low metal concen-trationsobtained from the trace metal analyses were confirmed with an ‘unpolluted status’ obtained for all sediment samples analyzed using the geochemical accumulation index formula. Results showed that metal concentrations in these areas are low and do not pose a threat to the survival of living organisms living in sediments or the surrounding environment.

Acyclovir Loaded Solid Lipid Nanoparticle Based Cream: A Novel Drug Delivery System

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
EL- Assal I. A. ◽  
Retnowati .
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Antiviral Agent ◽  
Study Drug ◽  
Particle Size Analysis ◽  
Stability Study ◽  
Size Analysis ◽  
Solid Lipid ◽  
Dermal Delivery

Objective of the present investigation was enthused by the possibility to develop solid lipid nanoparticles (SLNs) of hydrophilic drug acyclovir. Also study vitro and vivo drug delivery. Methods: Drug loaded SLNs (ACV-SLNs) were prepared by high pressure homogenization of aqueous surfactant solutions containing the drug-loaded lipids in the melted or in the solid state with formula optimization study (Different lipid concentration, drug loaded, homogenization / stirring speed and compritol 888ATO: drug ratio). ACV - SLN incorporated in cream base. The pH was evaluated and rheological study. Drug release was evaluated and compared with simple cream- drug, ACV – SLN with compritol 888ATO and marketed cream. The potential of SLN as the carrier for dermal delivery was studied. Results: Particle size analysis of SLNs prove small, smooth, spherical shape particle ranged from 150 to 200 nm for unloaded and from 330 to 444 nm for ACV loaded particles. The EE% for optimal formula is 72% with suitable pH for skin application. Rheological behavior is shear thinning and thixotropic. Release study proved controlled drug release for SLNs especially in formula containing compritol88 ATO. Stability study emphasized an insignificant change in SLNs properties over 6 month. In-vivo study showed significantly higher accumulation of ACV in stratum corneum, dermal layer, and receptor compartment compared with blank skin. Conclusion: AVC-loaded SLNs might be beneficial in controlling drug release, stable and improving dermal delivery of antiviral agent(s).

APSAS; an Automated Particle Size Analysis System

Circular ◽  
1985 ◽  
Author(s):  
Lawrence J. Poppe ◽  
A.H. Eliason ◽  
J.J. Fredericks
Keyword(s):  
Particle Size ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Analysis System
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