keyword
MENU ▼
Read by QxMD icon Read
search

Geochemistry

keyword
https://www.readbyqxmd.com/read/28726228/microwave-irradiation-and-citric-acid-assisted-seed-germination-and-phytoextraction-of-nickel-ni-by-brassica-napus-l-morpho-physiological-and-biochemical-alterations-under-ni-stress
#1
Mujahid Farid, Shafaqat Ali, Muhammad Rizwan, Rashid Saeed, Hafiz Muhammad Tauqeer, Rasham Sallah-Ud-Din, Ahmed Azam, Nighat Raza
The complex bio-geochemistry of soil allows pollutant to persist for a longer period of time which further decreased the fertility and natural composition of land. Nickel, an inorganic pollutant, coming from a wide range of industrial and manufacturing units possesses serious threat to soil degradation and crop productivity around the world. The present study was carried to evaluate the combined role of microwave irradiation (MR) and citric acid (CA) on the phytoextraction potential of Brassica napus L. under Ni stress...
July 20, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28724228/a-new-method-for-correlation-analysis-of-compositional-environmental-data-a-worked-example
#2
C Reimann, P Filzmoser, K Hron, P Kynčlová, R G Garrett
Most data in environmental sciences and geochemistry are compositional. Already the unit used to report the data (e.g., μg/l, mg/kg, wt%) implies that the analytical results for each element are not free to vary independently of the other measured variables. This is often neglected in statistical analysis, where a simple log-transformation of the single variables is insufficient to put the data into an acceptable geometry. This is also important for bivariate data analysis and for correlation analysis, for which the data need to be appropriately log-ratio transformed...
July 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28711007/carbon-dynamics-in-a-late-quaternary-age-coastal-limestone-aquifer-system-undergoing-saltwater-intrusion
#3
Eliza Bryan, Karina T Meredith, Andy Baker, Martin S Andersen, Vincent E A Post
This study investigates the inorganic and organic aspects of the carbon cycle in groundwaters throughout the freshwater lens and transition zone of a carbonate island aquifer and identifies the transformation of carbon throughout the system. We determined (14)C and (13)C carbon isotope values for both DIC and DOC in groundwaters, and investigated the composition of DOC throughout the aquifer. In combination with hydrochemical and (3)H measurements, the chemical evolution of groundwaters was then traced from the unsaturated zone to the deeper saline zone...
July 12, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28707854/a-eurasian-mineralogy-aleksandr-fersman%C3%A2-s-conception-of-the-natural-world
#4
Andy Bruno
Thoroughly a product of imperial Russia’s aristocratic culture, the mineralogist and geochemist Aleksandr Fersman rose to the top of the country’s scientific establishment after the Bolsheviks took control. He then remained a staunch supporter of various industrial projects through much of the Stalinist period. This essay puts Fersman’s thinking about the natural world in conversation with a quite distinctive mode of intellectual inquiry that developed contemporaneously. Eurasianism was a philosophical doctrine of a group of Russian émigrés who emphasized Russia’s unique status straddling Europe and Asia...
September 2016: Isis; An International Review Devoted to the History of Science and its Cultural Influences
https://www.readbyqxmd.com/read/28704663/effect-of-sulfide-on-as-iii-and-as-v-sequestration-by-ferrihydrite
#5
Zhixi Zhao, Shaofeng Wang, Yongfeng Jia
The sulfide-induced change in arsenic speciation is often coupled to iron geochemical processes, including redox reaction, adsorption/desorption and precipitation/dissolution. Knowledge about how sulfide influenced the coupled geochemistry of iron and arsenic was not explored well up to now. In this work, retention and mobilization of As(III) and As(V) on ferrihydrite in sulfide-rich environment was studied. The initial oxidation states of arsenic and the contact order of sulfide notably influenced arsenic sequestration on ferrihydrite...
June 30, 2017: Chemosphere
https://www.readbyqxmd.com/read/28702733/isotope-and-microelement-systematics-of-gallionella-sp-containing-bacterial-mats-from-the-northwest-of-the-east-european-platform
#6
S B Felitsyn, N A Alfimova
Microelement composition of Gallionella sp.-containing bacterial mats from the environs of St. Petersburg and isotope composition of organic carbon, strontium, and neodymium from these mats have been determined. Isotope and microelement systematics of iron oxides of bacterial origin characterize the geochemistry of aquafacies that contain ferrobacteria. Certain pre-Cambrian ferruginous quartzites have a similar composition; therefore, one may assume that bacterial oxidation of iron under continental conditions had occurred upon the formation of ironstone during the Precambrian...
May 2017: Doklady Biological Sciences: Proceedings of the Academy of Sciences of the USSR, Biological Sciences Sections
https://www.readbyqxmd.com/read/28692927/coal-emissions-adverse-human-health-effects-associated-with-ultrafine-nano-particles-role-and-resultant-engineering-controls
#7
Marcos L S Oliveira, Orlando G Navarro, Tito J Crissien, Bernardo F Tutikian, Kátia da Boit, Elba C Teixeira, Juan J Cabello, Dayana M Agudelo-Castañeda, Luis F O Silva
There are multiple elements which enable coal geochemistry: (1) boiler and pollution control system design parameters, (2) temperature of flue gas at collection point, (3) feed coal and also other fuels like petroleum coke, tires and biomass geochemistry and (4) fuel feed particle size distribution homogeneity distribution, maintenance of pulverisers, etc. Even though there is a large number of hazardous element pollutants in the coal-processing industry, investigations on micrometer and nanometer-sized particles including their aqueous colloids formation reactions and their behaviour entering the environment are relatively few in numbers...
July 7, 2017: Environmental Research
https://www.readbyqxmd.com/read/28685707/lead-and-selenite-adsorpion-at-water-goethite-interfaces-from-first-principles
#8
Kevin Leung, Louise J Criscenti
The complexation of toxic and/or radioactive ions on to mineral surfaces is an important topic in geochemistry. We apply periodic-boundary-conditions Density Functional Theory (DFT) molecular dynamics simulations to examine the coordination of Pb(II), SeO(3)(2-), and their contact ion pairs to goethite (101) and (210) surfaces. The multitude of Pb(II) adsorption sites and possibility of Pb(II)-induced FeOH deprotonation make this a complex problem. At surface sites where Pb(II) is coordinated to three FeO and/or FeOH groups, and with judicious choices of FeOH surface group protonation states, the predicted Fe-Pb distances are in good agreement with EXAFS measurements...
July 7, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28679119/biodegradable-plastic-bags-on-the-seafloor-a-future-threat-for-seagrass-meadows
#9
Elena Balestri, Virginia Menicagli, Flavia Vallerini, Claudio Lardicci
Marine plastic litter is a global concern. Carrier bags manufactured from non-biodegradable polymers constitute a large component of this litter. Because of their adverse impact on marine life, non-biodegradable bags have recently been replaced by biodegradable ones. However, growing evidence shows that these latter are not readily degradable in marine sediments and can alter benthic assemblages. The potential impact of biodegradable bags on seagrasses inhabiting sandy bottoms, which are the most widespread and productive ecosystems of the coastal zones, has been ignored...
July 2, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28672235/geochemistry-and-toxicity-of-a-large-slag-pile-and-its-drainage-complex-in-sudbury-ontario
#10
Laura Souter, Shaun A Watmough
Slag piles from mining activities are common worldwide, but in contrast to mine tailings the environmental impact of runoff from slag piles is less documented. This study was designed to assess the geochemistry and potential toxicity of water draining a large, 62.2ha slag pile in Sudbury, Ontario. The Coniston slag pile contains 12-20Mt of slag from smelting local Ni-Cu ore between 1913 and 1972. Slag leaching experiments confirmed slag is a source of sulphate (SO4), heavy metals (including Fe, Al, Ni, Co, Cu, Zn, Pb, Cr, Mn) and base cations (Ca, K, Mg, Na)...
June 30, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28659879/co-registered-geochemistry-and-metatranscriptomics-reveal-unexpected-distributions-of-microbial-activity-within-a-hydrothermal-vent-field
#11
Heather C Olins, Daniel R Rogers, Christina Preston, William Ussler, Douglas Pargett, Scott Jensen, Brent Roman, James M Birch, Christopher A Scholin, M Fauzi Haroon, Peter R Girguis
Despite years of research into microbial activity at diffuse flow hydrothermal vents, the extent of microbial niche diversity in these settings is not known. To better understand the relationship between microbial activity and the associated physical and geochemical conditions, we obtained co-registered metatranscriptomic and geochemical data from a variety of different fluid regimes within the ASHES vent field on the Juan de Fuca Ridge. Microbial activity in the majority of the cool and warm fluids sampled was dominated by a population of Gammaproteobacteria (likely sulfur oxidizers) that appear to thrive in a variety of chemically distinct fluids...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28654810/metal-and-metalloid-distribution-in-different-environmental-compartments-of-the-middle-xingu-river-in-the-amazon-brazil
#12
Danielle Regina Gomes Ribeiro, Henrique Faccin, Thaís Ramos Dal Molin, Leandro Machado de Carvalho, Lílian Lund Amado
Concentrations of As, Cd, Cu, Cr, Pb, Hg, and Ni were analyzed during rainy and dry seasons in water, sediment, soil, and two fish species. The analysis took place at four points in the Xingu River, one point in the Fresco River, and two mining pits in the southeastern area of the Eastern Amazon, Brazil. In the water, the total concentration of As (>0.14μg/L) was higher than the local reference values at all sampling points and in both seasons. Ordination analysis (PCA) highlighted As and Cu elements in the water...
June 24, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28645085/extending-the-functionality-of-the-slurry-ferrihydrite-dgt-method-performance-evaluation-for-the-measurement-of-vanadate-arsenate-antimonate-and-molybdate-in-water
#13
Shu Zhang, Paul N Williams, Chun-Yang Zhou, Lena Q Ma, Jun Luo
The monitoring of oxyanions in waters, presents significant challenges due to their relatively low concentrations, and a characteristically changeable/unstable/reactive geochemistry with high spatial and temporal turnover. This results in a very heterogeneous pattern of mobility and bioavailability, which is difficult to capture reliably and in a cost effective manner. The diffusive gradients in thin-films (DGT) technique is a popular analytical tool for testing water quality, primarily because it provides a time-integrated measurement...
June 18, 2017: Chemosphere
https://www.readbyqxmd.com/read/28644616/importance-of-a-fully-anharmonic-treatment-of-equilibrium-isotope-fractionation-properties-of-dissolved-ionic-species-as-evidenced-by-li-aq
#14
Romain Dupuis, Magali Benoit, Mark E Tuckerman, Merlin Méheut
Equilibrium fractionation of stable isotopes is critically important in fields ranging from chemistry, including medicinal chemistry, electrochemistry, geochemistry, and nuclear chemistry, to environmental science. The dearth of reliable estimates of equilibrium fractionation factors, from experiment or from natural observations, has created a need for accurate computational approaches. Because isotope fractionation is a purely quantum mechanical phenomenon, exact calculation of fractionation factors is nontrivial...
June 23, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28637853/trophic-state-changes-can-affect-the-importance-of-methane-derived-carbon-in-aquatic-food-webs
#15
Jos Schilder, Maarten van Hardenbroek, Paul Bodelier, Emiliya P Kirilova, Markus Leuenberger, André F Lotter, Oliver Heiri
Methane-derived carbon, incorporated by methane-oxidizing bacteria, has been identified as a significant source of carbon in food webs of many lakes. By measuring the stable carbon isotopic composition (δ(13)C values) of particulate organic matter, Chironomidae and Daphnia spp. and their resting eggs (ephippia), we show that methane-derived carbon presently plays a relevant role in the food web of hypertrophic Lake De Waay, The Netherlands. Sediment geochemistry, diatom analyses and δ(13)C measurements of chironomid and Daphnia remains in the lake sediments indicate that oligotrophication and re-eutrophication of the lake during the twentieth century had a strong impact on in-lake oxygen availability...
June 28, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28635416/arsenic-and-fluoride-co-contamination-in-shallow-aquifers-from-agricultural-suburbs-and-an-industrial-area-of-punjab-pakistan-spatial-trends-sources-and-human-health-implications
#16
Abida Farooqi, Jawairia Sultana, Noshin Masood
Release of arsenic (As) and fluoride (F(-)) species into groundwater is a serious health concern around the world. The present study was the first systematic baseline study conducted in Rahim Yar Khan district, Punjab, focusing on As and F(-) contamination in groundwater. A total of 51 representative groundwater samples comprising of 44 samples from agricultural suburbs and 7 from an industrial base were analysed. Statistical parameters, principal component analysis-multiple linear regression (PCA-MLR) and health risk assessment model were used to investigate the hydro geochemistry, spatial patterns, interrelation, source contribution and associated health risks of high As and F(-) in groundwater of the study area...
January 1, 2017: Toxicology and Industrial Health
https://www.readbyqxmd.com/read/28624636/water-geochemistry-of-shallow-lakes-from-the-southeastern-pampa-plain-argentina-and-their-implications-on-mollusk-shells-preservation
#17
Paula A Cristini, Eleonor Tietze, Claudio G De Francesco, Daniel E Martínez
A seasonal sampling of sediments, column and interstitial water for physico-chemical analysis were performed in littoral and open water areas in three freshwater shallow lakes (Nahuel Rucá, Las Mostazas and Los Carpinchos) from Southeastern Pampa plain, Argentina. The main objective of the present study is to evaluate how the characteristics of the depositional environments could be affecting mollusk shell preservation. These lakes are very shallow (2m) and are characterized by an extensive littoral area, dominated by the emergent macrophyte Schoenoplectus californicus, which forms a complete ring around the lake, and an open water area, in general free of vegetation...
June 15, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28609848/geochemical-landscapes-as-drivers-of-trace-and-toxic-element-profiles-in-wild-red-deer-cervus-elaphus
#18
Andrew S French, David Shaw, Stuart W Gibb, Mark A Taggart
Tissue concentrations of essential trace and toxic elements in red deer (Cervus elaphus) are associated with the plants, soil and water they ingest. As such, variation in tissue concentrations is associated with variation in local geochemistry and bioavailability of elements. Physiological factors such as liver fluke (Fasciola hepatica) infection, breeding status, and in-tissue element interactions may also affect tissue concentrations, though their effects in red deer are not well understood. The primary objective of this study was therefore to survey wild red deer liver element concentrations across a range of geographically distinct populations during the Scottish red deer stalking season; and, in so doing, establishes element reference ranges while also exploring geographic and temporal variation and physiological factors...
June 9, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28595096/occurrence-and-mobility-of-toxic-elements-in-coals-from-endemic-fluorosis-areas-in-the-three-gorges-region-sw-china
#19
Yan Xiong, Tangfu Xiao, Yizhang Liu, Jianming Zhu, Zengping Ning, Qingxiang Xiao
Fluorine (F) is a topic of great interest in coal-combustion related endemic fluorosis areas. However, little extent research exists regarding the environmental geochemistry of toxic elements that are enriched in coals and coal wastes in traditional endemic fluorosis areas, particularly focusing on their occurrences and mobilities during the weathering-leaching processes of coals and coal wastes in the surface environment. This paper addressed the issue of toxic elements in coals and coal wastes in the Three Gorges Region, Southwest (SW) China, where endemic fluorosis has historically prevailed, and investigated the distribution, occurrence, mobility features, and associated potential health risks...
June 5, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28580550/magnetic-signature-geochemistry-and-oral-bioaccessibility-of-technogenic-metals-in-contaminated-industrial-soils-from-sindos-industrial-area-northern-greece
#20
Anna Bourliva, Lambrini Papadopoulou, Elina Aidona, Katerina Giouri
The objective of this study was to assess the contamination level of potentially harmful elements (PHEs) in industrial soils and how this relates to environmental magnetism. Moreover, emphasis was given to the determination of the potential mobile fractions of typically "technogenic" metals. Therefore, magnetic and geochemical parameters were determined in topsoils (0-20 cm) collected around a chemical industry in Sindos Industrial Area, Thessaloniki, Greece. Soil samples were presented significantly enriched in "technogenic" metals such Cd, Pb, and Zn, while cases of severe soil contamination were observed in sampling sites north-west of the industrial unit...
July 2017: Environmental Science and Pollution Research International
keyword
keyword
93618
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"