Leaching of copper, chromium, and arsenic through some free-draining New Zealand soils

Soil Research ◽  
1996 ◽  
Vol 34 (4) ◽  
pp. 583 ◽  
Author(s):  
PL Carey ◽  
RG Mclaren ◽  
KC Cameron ◽  
JR Sedcole
Keyword(s):  
New Zealand ◽  
Chemical Properties ◽  
Physical Structure ◽  
Breakthrough Curves ◽  
Undisturbed Soil ◽  
Soil Monolith ◽  
Copper Chromium ◽  
Growth Differences ◽  
Physical And Chemical ◽  
Parameter Values

Concentrated toxic solutions of copper, chromium, and arsenic (CCA) are used extensively in the New Zealand timber preservation industry. A 2% w/v solution containing cupric, dichromate, and arsenate ions was leached through undisturbed soil monolith lysimeters containing the surface and subsurface horizons of 2 free-draining New Zealand soils. The resulting breakthrough curves were successfully modelled using the Gompertz equation for biomass growth. Differences between soil horizons in the fitted Gompertz parameter values were related to differences in soil physical and chemical properties affecting leaching. Results were compared to those from a previous study investigating pulse leaching of a concentrated CCA solution of similar ion ratio using the same soils. Generally, solution leaching produced breakthrough curves influenced more by the soil's physical structure and less by kinetic processes (i.e. sorption and diffusion). This was in part due to the high metal concentrations of the CCA solution and the decreased contact time between soil and solute in the solution leaching experiment. The relative ease of solute ion breakthrough increased in the order copper < arsenate < dichromate. The study suggests that further research is required to assess management implications for spills of these heavy metal ions to soils to prevent leaching or runoff to ground and surface water.

Review of Physical and Chemical Properties of Perfluorooctanyl sulphonate (PFOS) with Respect to its Potential Contamination on the Environment

2012 ◽  
Vol 518-523 ◽  
pp. 2183-2191 ◽  
Author(s):  
Sheng Zhang ◽  
David N Lerner
Keyword(s):  
Chemical Properties ◽  
Hydrocarbon Fuel ◽  
The United States ◽  
Breakthrough Curves ◽  
Film Forming ◽  
Perfluorinated Surfactants ◽  
Blood Banks ◽  
Single Well ◽  
Physical And Chemical ◽  
By Products

Perfluorinated surfactants have emerged as priority environmental contaminants due to their detection in environmental and biological matrices as well as concerns regarding their persistence and toxicity. They have been found in groundwater, particularly at sites used for training firefighters. They do not biodegrade easily in groundwater, and are not retarded during transport. The most common chemical is Perfluorooctanyl Sulphonate (PFOS), which is mainly used in aqueous film forming foam (AFFF) to extinguish hydrocarbon-fuel fires. It is also used in many herbicide and insecticide formulations, cosmetics, greases and lubricants, paints, polishes, and adhesives. PFOS and related fluoro-organic chemicals have been used since the 1950s. A quantity of fluorosurfactants and related products are still in use all over the world. Intensive studies over the last few years discovered that PFOS and certain by-products were both ubiquitous in the environment and highly persistent. PFOS does not biodegrade in the environment and very limited degradation has been observed in wastewater treatment. The breakthrough curves of a single-well push-pull test indicated that there was no retardation for PFOS as well. It was detected in part-per-billion levels in blood samples obtained from blood banks in the United States, Japan, Europe, and China. There have been more and more reports on the accumulation and effect of PFOS in wild animals’ liver, serum and muscle as well. This suggests that PFOS can bioaccumulate to higher levels of the food chain.

The Physical and Chemical Properties of MoS2(1-x)Te2x Alloy Synthesized by Co-sputtering and Chalcogenization and Their Dependence on Fabrication Conditions

MRS Advances ◽  
2020 ◽  
Vol 5 (31-32) ◽  
pp. 1635-1642 ◽  
Author(s):  
Yusuke Hibino ◽  
Kota Yamazaki ◽  
Yusuke Hashimoto ◽  
Yuya Oyanagi ◽  
Naomi Sawamoto ◽  
...  
Keyword(s):  
Phase Separation ◽  
Band Structure ◽  
Chemical Properties ◽  
Physical Structure ◽  
Band Alignment ◽  
Physical And Chemical Properties ◽  
Amorphous Nature ◽  
Physical And Chemical ◽  
Structure Evaluation ◽  
And Chemical Properties

ABSTRACTMoS2(1-x)Te2x, the alloy of MoS2 and MoTe2 was fabricated with just co-sputtering and the combination of co-sputtering with following thermal treatment in chalcogen ambient. Phase separation, where MoTe2 was segregated rather than S and Te being uniformly distributed, was observed for some samples. From the physical structure evaluation using XRD, it was shown that the samples that was sulfurized after unintentional oxidation during shelf time exhibited no phase separation. It was suggested that oxidation of Mo or amorphous nature of the film at the chalcogenization stage may prevent the phase separation. In addition, some samples were stored in desiccator for stability evaluation. It was revealed that the samples undergo oxidation to different extent depending on the carrier gas used in tellurization. Finally, the bandgap and band structure was evaluated for samples with different Te concentration. The bandgap showed bowing behavior for different Te concentration with the bowing parameter b = -1.21 eV. Combined with the bandgap evaluation, the valence analysis with XPS showed that the band structure shifted according to the Te concentration. The shift in bandgap allows flexible band alignment which is expected to expand the materials applicability.

Influence of soil structure on sulfate leaching from a silt loam

Soil Research ◽  
1992 ◽  
Vol 30 (4) ◽  
pp. 443 ◽  
Author(s):  
CDA Mclay ◽  
KC Cameron ◽  
RG Mclaren
Keyword(s):  
Soil Structure ◽  
Packed Column ◽  
Breakthrough Curves ◽  
Natural Soil ◽  
Silt Loam ◽  
Soil Columns ◽  
Undisturbed Soil ◽  
Soil Monolith ◽  
Sulfate Leaching ◽  
Soil Lysimeters

The influence of soil structure on sulfate leaching from a silt loam soil was assessed by comparing the results of leaching experiments conducted using undisturbed soil monolith lysimeters and re-packed soil columns. A pulse application of sulfate solution was leached through both soil systems under non-ponded infiltration conditions. Breakthrough curves (BTCs) from the undisturbed soil lysimeters were poly-modal compared with the uni-modal curves observed in re-packed column experiments. The poly-modal BTC is considered to result from sulfate leached through isolated porosity regions within the undisturbed soil monolith. Sulfate leaching rates were faster through the undisturbed soil lysimeters and this was attributed to solute transport through the natural soil macropore system, which is retained in the undisturbed soil but lost in the repacked soil columns. Leaching through soil macropores therefore can result in considerable losses of sulfur from silt loam textured soils.

scholarly journals Seasonal variations in furs of Gabaly and New Zealand white rabbits and their crossbred under Egyptian semi-arid conditions

2020 ◽  
Vol 28 (1) ◽  
pp. 49
Author(s):  
A.I. Nasr ◽  
E.A. Taha ◽  
S.B. Naglaa ◽  
D.G. Essa
Keyword(s):  
New Zealand ◽  
Seasonal Variations ◽  
Fibre Diameter ◽  
Chemical Properties ◽  
Skin Layer ◽  
Diameter Distribution ◽  
Arid Conditions ◽  
Physical Traits ◽  
Physical And Chemical ◽  
Semi Arid

The effect of breed and season on rabbits’ fur characteristics under Egyptian semi-arid conditions was studied in this research. Fifty-nine male rabbits aged 3-3.5 mo of Gabaly (GB, n=21) and New Zealand White (NZW, n=27) breeds and their crossbred (NZW×GB, n=11) were studied during two subsequent seasons; summer (n=31) and winter (n=28). Skin samples were taken pre-slaughtering to determine the histological parameters, skin layer thicknesses and physical traits of fur fibres. After slaughter, rabbits’ furs were chrome tanned to determine physical and chemical properties. Results showed that all histological parameters of follicle dimensions were affected (<em>P</em>&lt;0.01) by season, breed and their interaction. In summer, primary follicles had larger follicle dimensions and produced coarser fibres than in winter, whereas opposite results were observed for the secondary follicles. Additionally, the uniformity of fibre diameter distribution and hair length of furs were higher (<em>P</em>&lt;0.01) in summer than in winter. Results indicated the role of the seasonal variations in body coat to accommodate the climatic changes. NZW rabbits were superior (<em>P</em>&lt;0.01) in most histological parameters of follicle dimensions, followed by NZW×GB crossbred and finally GB rabbits, while NZW×GB crossbred produced finer (<em>P</em>&lt;0.01) fur fibre than NZW and GB rabbits. Otherwise, influence of season and breed were negligible on the skin layer thickness values and the physical and chemical fur properties. Consequently, the study concluded that tanned rabbit furs are suitable for manufacturing leather garments when used alone, while reinforcing the fur with textile padding may increase their utility for other leather manufacturing purposes.

Automated statistical matching of multiple tephra records exemplified using five long maar sequences younger than 75 ka, Auckland, New Zealand

2014 ◽  
Vol 82 (2) ◽  
pp. 405-419 ◽  
Author(s):  
Rebecca M. Green ◽  
Mark S. Bebbington ◽  
Shane J. Cronin ◽  
Geoff Jones
Keyword(s):  
New Zealand ◽  
Sediment Cores ◽  
Chemical Properties ◽  
Volcanic Field ◽  
Optimization Techniques ◽  
Auckland Volcanic Field ◽  
Individual Site ◽  
Complicating Factors ◽  
Physical And Chemical ◽  
Age Determinations

AbstractDetailed tephrochronologies are built to underpin probabilistic volcanic hazard forecasting, and to understand the dynamics and history of diverse geomorphic, climatic, soil-forming and environmental processes. Complicating factors include highly variable tephra distribution over time; difficulty in correlating tephras from site to site based on physical and chemical properties; and uncertain age determinations. Multiple sites permit construction of more accurate composite tephra records, but correctly merging individual site records by recognizing common events and site-specific gaps is complex. We present an automated procedure for matching tephra sequences between multiple deposition sites using stochastic local optimization techniques. If individual tephra age determinations are not significantly different between sites, they are matched and a more precise age is assigned. Known stratigraphy and mineralogical or geochemical compositions are used to constrain tephra matches. We apply this method to match tephra records from five long sediment cores (≤ 75 cal ka BP) in Auckland, New Zealand. Sediments at these sites preserve basaltic tephras from local eruptions of the Auckland Volcanic Field as well as distal rhyolitic and andesitic tephras from Okataina, Taupo, Egmont, Tongariro, and Tuhua (Mayor Island) volcanic centers. The new correlated record compiled is statistically more likely than previously published arrangements from this area.

scholarly journals Milk from different species on physicochemical and microstructural yoghurt properties

2019 ◽  
Vol 49 (6) ◽  
Author(s):  
Felipe Santana Vianna ◽  
Anna Carolina Vilhena da Cruz Silva Canto ◽  
Bruno Costa-Lima ◽  
Ana Paula Salim ◽  
Celso Fasura Balthazar ◽  
...  
Keyword(s):  
Apparent Viscosity ◽  
Dairy Industry ◽  
Chemical Properties ◽  
Physical Structure ◽  
Microstructural Properties ◽  
Lipid Contents ◽  
Homogeneous Matrix ◽  
Size Heterogeneity ◽  
Parameter Values ◽  
Water Holding

ABSTRACT: The aim of the present research was to evaluate differences in chemical properties and physical structure of yoghurt produced with milk from different species (sheep, cow, and goat). For each trial, whole raw sheep (S), cow (C), and goat (G) milk were used to manufacture 4L of yoghurts (Y) from each species (SY, CY, and GY, respectively). The SY demonstrated the greatest (P<0.05) values of total solids, protein, and lipid contents, reflecting on greater (P<0.05) firmness, apparent viscosity and water-holding capacity, and lower (P<0.05) syneresis index than CY and GY. Consequently, SY exhibited a more compact microstructure and homogeneous matrix with fewer pores. Furthermore, CY and GY microstructure contained a greater number of pores, which exhibited greater size heterogeneity than SY. Therefore, based on the evaluated physicochemical and microstructural properties of yoghurt, SY demonstrated the most desirable parameter values for dairy industry representing an alternative substitution for cow’s milk yogurt.

scholarly journals Conditioning Fixed-Bed Filters with Fine Fractions of Granulated Iron Hydroxide (µGFH)

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1324 ◽  
Author(s):  
Inga Hilbrandt ◽  
Aki Ruhl ◽  
Martin Jekel
Keyword(s):  
Iron Hydroxide ◽  
Fixed Bed ◽  
Fine Fraction ◽  
Ferric Hydroxide ◽  
Chemical Properties ◽  
Breakthrough Curves ◽  
Homogeneous Distribution ◽  
Removal Of Heavy Metals ◽  
Evaluating Methods ◽  
Physical And Chemical

The fine fraction of granular ferric hydroxide (µGFH, <0.3 mm) is a promising adsorbent for the removal of heavy metals and phosphate, but properties of µGFH were hitherto not known. The present study aimed at characterizing µGFH regarding its physical and chemical properties and at evaluating methods for the conditioning of fixed-bed filters in order to develop a process that combines filtration and adsorption. Conditioning was done at different pH levels and for different particle sizes. Anthracite, coke, pumice and sand were studied as potential carrier materials. A method for the evaluation of the homogeneity of the iron hydroxide particle distribution on pumice filter grains using picture analysis was developed. Pre-washed pumice (pH 8.5) proved to lead to high embedment and a homogeneous distribution of µGFH. Filter runs with phosphate (2 mg/L P) showed similar breakthrough curves for the embedded fine fraction adsorbent and for conventional GFH.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

Biophysical Measurement of Molecular Weight of Foot-and-Mouth Disease RNA Fragments

1974 ◽  
Vol 32 ◽  
pp. 262-263
Author(s):  
Sydney S. Breese ◽  
Howard L. Bachrach
Keyword(s):  
Chemical Properties ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Distilled Water ◽  
Bovine Plasma ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Carbon Coated ◽  
Rna Fragments ◽  
Physical And Chemical

Continuing studies on the physical and chemical properties of foot-and-mouth disease virus (FMDV) have included electron microscopy of RNA strands released when highly purified virus (1) was dialyzed against demlneralized distilled water. The RNA strands were dried on formvar-carbon coated electron microscope screens pretreated with 0.1% bovine plasma albumin in distilled water. At this low salt concentration the RNA strands were extended and were stained with 1% phosphotungstic acid. Random dispersions of strands were recorded on electron micrographs, enlarged to 30,000 or 40,000 X and the lengths measured with a map-measuring wheel. Figure 1 is a typical micrograph and Fig. 2 shows the distributions of strand lengths for the three major types of FMDV (A119 of 6/9/72; C3-Rezende of 1/5/73; and O1-Brugge of 8/24/73.

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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