keyword
MENU ▼
Read by QxMD icon Read
search

Chemical speciation

keyword
https://www.readbyqxmd.com/read/28817281/linking-solution-structures-and-energetics-thorium-nitrate-complexes
#1
Suntharalingam Skanthakumar, Geng Bang Jin, Jian Lin, Valérie Vallet, Lynda Soderholm
Seeking predictive insights into how metal-ion speciation impacts solution chemistry as well as the composition and structure of solid-precipitates, thorium correlations, with both solvent and other solute ions, were quantitatively probed in a series of acidic, nitrate/perchlorate solutions held at constant ionic strength. Difference pair-distribution functions (dPDF), obtained from high-energy x-ray scattering (HEXS) data, provide unprecedented structural information on the number of Th ligating ions in solution and how they change with increasing nitrate concentration...
August 17, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28816442/characterization-of-primary-organic-aerosol-from-domestic-wood-peat-and-coal-burning-in-ireland
#2
Chunshui Lin, Darius Ceburnis, Stig Michael Hellebust, Paul Buckley, John Charles Wenger, Francesco Canonaco, Andre S H Prevot, Ru-Jin Huang, Colin O'Dowd, Jurgita Ovadnevaite
An Aerosol Chemical Speciation Monitor (ACSM) was deployed to study the primary non-refractory submicron particulate matter emissions from burning of commercially available solid fuels (peat, coal, and wood) typically used in European domestic fuel stoves. Organic mass spectra (MS) from burning wood, peat, and coal were characterized and inter-compared for factor analysis against ambient data. The reference profiles characterized in this study were used to estimate the contribution of solid fuel sources, along with oil combustion, to ambient pollution in Galway, Ireland using the multilinear engine (ME-2)...
August 17, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28812654/transitions-between-phases-of-genomic-differentiation-during-stick-insect-speciation
#3
Rüdiger Riesch, Moritz Muschick, Dorothea Lindtke, Romain Villoutreix, Aaron A Comeault, Timothy E Farkas, Kay Lucek, Elizabeth Hellen, Víctor Soria-Carrasco, Stuart R Dennis, Clarissa F de Carvalho, Rebecca J Safran, Cristina P Sandoval, Jeff Feder, Regine Gries, Bernard J Crespi, Gerhard Gries, Zach Gompert, Patrik Nosil
Speciation can involve a transition from a few genetic loci that are resistant to gene flow to genome-wide differentiation. However, only limited data exist concerning this transition and the factors promoting it. Here, we study phases of speciation using data from >100 populations of 11 species of Timema stick insects. Consistent with early phases of genic speciation, adaptive colour-pattern loci reside in localized genetic regions of accentuated differentiation between populations experiencing gene flow...
February 17, 2017: Nature ecology & evolution
https://www.readbyqxmd.com/read/28811029/use-of-diffusive-gradient-in-thin-films-for-in-situ-measurements-a-review-on-the-progress-in-chemical-fractionation-speciation-and-bioavailability-of-metals-in-waters
#4
REVIEW
Amauri Antonio Menegário, Lauren N Marques Yabuki, Karen S Luko, Paul N Williams, Daniel M Blackburn
Chemical fractionation, speciation analysis and bioavailability of metals and metalloids in waters have received increased attention in recent years. However, this interest is not matched by progress in improving species integrity during standard 'grab' sample collection, processing and storage. Time-averaged, low disturbance sampling, in situ, of trace element species, in particular, is a more reliable approach for environmental chemical surveillance and methods based on the diffusive gradients in thin films (DGT) technique stand out as one of the most widely used of the passive sampler classes, and hence will be the primary focus of this review...
August 29, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28802224/speciation-of-the-trivalent-f-elements-eu-iii-and-cm-iii-in-digestive-media
#5
Claudia Wilke, Astrid Barkleit, Thorsten Stumpf, Atsushi Ikeda-Ohno
In case radioactive materials are released into the environment, their incorporation into our digestive system would be a significant concern. Trivalent f-elements, i.e., trivalent actinides and lanthanides, could potentially represent a serious health risk due to their chemo- and radiotoxicity, nevertheless the biochemical behavior of these elements are mostly unknown even to date. This study, therefore, focuses on the chemical speciation of trivalent f-elements in the human gastrointestinal tract. To simulate the digestive system artificial digestive juices (saliva, gastric juice, pancreatic juice and bile fluid) were prepared...
August 4, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28800536/fate-of-metals-before-and-after-chemical-extraction-of-incinerated-sewage-sludge-ash
#6
Jiang-Shan Li, Daniel C W Tsang, Qi-Ming Wang, Le Fang, Qiang Xue, Chi Sun Poon
Chemical extraction of incinerated sewage sludge ash (ISSA) can effectively recycle P, but it may change the speciation and mobility of the remaining metals. This study investigated the changes of the leaching potential and distribution of metals in the chemically extracted ISSA. Batch extraction experiments with different extractants, including inorganic acids, organic acids, and chelating agents, were conducted on the ISSA collected from a local sewage sludge incinerator. The extraction of Zn, Cu, Pb, Ni, Cd, Ba, Cr and As from the ISSA and the corresponding changes of the mobility and speciation were examined...
August 5, 2017: Chemosphere
https://www.readbyqxmd.com/read/28781183/selenium-speciation-in-phosphate-mine-soils-and-evaluation-of-a-sequential-extraction-procedure-using-xafs
#7
Jessica E Favorito, Todd P Luxton, Matthew J Eick, Paul R Grossl
Selenium is a trace element found in western US soils, where ingestion of Se-accumulating plants has resulted in livestock fatalities. Therefore, a reliable understanding of Se speciation and bioavailability is critical for effective mitigation. Sequential extraction procedures (SEP) are often employed to examine Se phases and speciation in contaminated soils but may be limited by experimental conditions. We examined the validity of a SEP using X-ray absorption spectroscopy (XAS) for both whole and a sequence of extracted soils...
August 3, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28779895/whole-cell-bioreporters-and-risk-assessment-of-environmental-pollution-a-proof-of-concept-study-using-lead
#8
Xiaokai Zhang, Boqiang Qin, Jianming Deng, Mona Wells
As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment...
August 2, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28774791/an-integrative-approach-to-untangling-species-delimitation-in-the-cataglyphis-bicolor-desert-ant-complex-in-israel
#9
P A Eyer, R Seltzer, T Reiner-Brodetzki, A Hefetz
Although extensive research has been carried out on the desert ants in the genus Cataglyphis in recent years, some of the specific intra- and interspecific relationships remain elusive. The present study disentangles the phylogenetic relationships among the C. bicolor complex in Israel using an integrative approach based on genetic markers, morphometric measurements, and chemical analyses (cuticular hydrocarbons). Several species delimitation approaches based on four nuclear, two mitochondrial, and eleven microsatellite markers, as well as 16 body measurements and 56 chemical variables, were employed to deciphering the occurrence of cryptic species in our data set...
July 31, 2017: Molecular Phylogenetics and Evolution
https://www.readbyqxmd.com/read/28743946/identification-of-the-eskape-pathogens-by-mass-spectrometric-analysis-of-microbial-membrane-glycolipids
#10
Lisa M Leung, William E Fondrie, Yohei Doi, J Kristie Johnson, Dudley K Strickland, Robert K Ernst, David R Goodlett
Rapid diagnostics that enable identification of infectious agents improve patient outcomes, antimicrobial stewardship, and length of hospital stay. Current methods for pathogen detection in the clinical laboratory include biological culture, nucleic acid amplification, ribosomal protein characterization, and genome sequencing. Pathogen identification from single colonies by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of high abundance proteins is gaining popularity in clinical laboratories...
July 25, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28738527/evaluation-of-heavy-metal-mobilization-in-creek-sediment-influence-of-rac-values-and-ambient-environmental-factors
#11
Guannan Liang, Bo Zhang, Mao Lin, Simiao Wu, Hao Hou, Jia Zhang, Guangren Qian, Xin Huang, Jizhi Zhou
The risk assessment code (RAC) is a common method for assessing heavy metal (HM) mobility and their potential health risks, based on HM total concentration and chemical speciation. In this study, both the RAC and the influence of ambient environmental factors were investigated in a river sediment system. Sixty-eight sediment samples were collected from the main river system in Shanghai, China. The total concentration and chemical speciation of Cu, Zn, Ni, Pb, Cd, Cr, As, and Hg were determined in the samples...
July 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28731295/biogeochemistry-of-lead-its-release-to-the-environment-and-chemical-speciation
#12
Jay T Cullen, Jason McAlister
Lead (Pb) is a metal that is not essential for life processes and proves acutely toxic to most organisms. Compared to other metals Pb is rather immobile in the environment but still its biogeochemical cycling is greatly perturbed by human activities. In this review we present a summary of information describing the physical and chemical properties of Pb, its distribution in crustal materials, and the processes, both natural and anthropogenic, that contribute to the metal's mobilization in the biosphere. The relatively high volatility of Pb metal, low melting point, its large ionic radius, and its chemical speciation in aquatic systems contributes to its redistribution by anthropogenic and natural processes...
April 10, 2017: Metal Ions in Life Sciences
https://www.readbyqxmd.com/read/28730356/seasonal-variation-of-chemical-composition-and-source-apportionment-of-pm2-5-in-pune-india
#13
Ranjeeta D Gawhane, Pasumarthi Surya Prakasa Rao, Krishnakant B Budhavant, Vinayak Waghmare, Dhananjay C Meshram, Pramod D Safai
Particulate matter with size less than or equal to 2.5 μm (PM2.5) samples were collected from an urban site Pune, India, during April 2015 to April 2016. The samples were analyzed for various chemical constituents, including water soluble inorganic ions, organic carbon (OC), and elemental carbon (EC). The yearly mean total mass concentration of PM2.5 at Pune was 37.3 μg/m(3), which is almost four times higher than the annual WHO standard (10 μg/m(3)), and almost equal to that recommended by the Central Pollution Control Board, India (40 μg/m(3))...
July 20, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28728128/radionuclide-biokinetics-in-the-russian-sturgeon-and-phylogenetic-consistencies-with-cartilaginous-and-bony-marine-fishes
#14
Ross A Jeffree, Scott J Markich, Francois Oberhaensli, Jean-Louis Teyssie
The biokinetics of eight radionuclides ((241)Am, (109)Cd, (134)Cs, (75)Se, (54)Mn, (110m)Ag, (65)Zn, (60)Co) absorbed from the aquatic medium by juvenile Russian sturgeon (Acipenser gueldenstaedtii) were experimentally determined in fresh (0.42‰) and brackish (9.0‰) waters, of a similar salinity range to the Caspian Sea, and in conjunction with chemical speciation modelling. Uptake and loss rate constants were determined for each radionuclide for a 14 day exposure at each salinity and during 28 days of exposure to radionuclide-free conditions...
July 17, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28726692/chemical-speciation-of-trace-metals-in-the-industrial-sludge-of-dhaka-city-bangladesh
#15
Md Saiful Islam, Md Habibullah Al-Mamun, Ye Feng, Masahiro Tokumura, Shigeki Masunaga
The objective of this study was to assess total concentration and chemical fractionation of trace metals in the industrial wastewater and sludge collected from seven different types of industries in Dhaka City, Bangladesh. The sludge from industries is either dumped on landfills or reused as secondary resources in order to preserve natural resources. Metals were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The ranges of Cr, Ni, Cu, As, Cd, and Pb in the sludges were 1.4-9,470, 4.8-994, 12...
July 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28718696/tumor-induced-disorder-of-iron-metabolism-in-major-organs-a-new-insight-from-chemical-speciation-of-iron
#16
Rujie Chen, Guangcun Chen
Objective To investigate the evolution of iron speciation in major organs of tumor-bearing mice and its role in cancer formation and cancer-associated complications. Methods The concentration and chemical speciation of iron in the spleen, liver, lung, kidney, heart, blood, muscle, and tumor tissue of healthy mice and tumor-bearing mice were studied by synchrotron radiation-based total reflection X-ray fluorescence spectrometry (SR-TXRF) coupled with X-ray absorption spectroscopy (XAS). Results The TXRF and XAS results showed that the iron content, especially the ferritin content, significantly decreased in the blood and spleen but significantly increased in the liver, lung, and muscle of mice after tumor implantation...
January 1, 2017: Journal of International Medical Research
https://www.readbyqxmd.com/read/28714679/spectroscopic-study-of-the-reversible-chemical-reduction-and-reoxidation-of-substitutional-cr-ions-in-sr2tio4
#17
Keith A Lehuta, Anubhab Haldar, Dongming Zhou, Kevin R Kittilstved
The solid-state synthesis and controllable speciation of Cr dopants in the layered perovskite Sr2TiO4 is reported. We employed a chemical reduction procedure with NaBH4 at relatively mild temperatures (<450 °C) to impart sensitive control over the relative concentration of Cr(3+) dopants, the charge-state of oxygen-vacancy defects, and presence of Ti(3+) defects in highly reduced Cr-doped Sr2TiO4. The electron paramagnetic resonance (EPR) spectra of the reduced powder samples reveal a 12-fold increase in the Cr(3+) concentration within the axially compressed Ti(4+)-site of the Sr2TiO4 host...
August 7, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28710730/remediation-of-chromium-contaminated-soil-by-electrokinetics-and-electrokinetics-coupled-with-caal-ldh-permeable-reaction-barrier
#18
Yunfeng Xu, Wei Xia, Hetian Hou, Jia Zhang, Guangren Qian
The remediation of Cr(VI)-contaminated soil was investigated by electrokinetic (EK) and permeable-reactive-barrier assisted electrokinetic (EK-PRB). The medium of PRB was hydrocalumite (CaAl-LDH). The results showed that removal efficiency of hexavalent chromium (Cr(VI)) in EK-PRB and EK system was 96.49 and 85.50%, respectively. Simultaneously, the removal efficiency of total chromium (TCr) was 69.34 and 40.97% after 120-h treatment. The XRD, FTIR, and XPS analyses indicated that the reactive barrier media of CaAl-LDH successfully captured the chromium...
July 15, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28702905/assessment-of-biofilm-changes-and-concentration-depth-profiles-during-arsenopyrite-oxidation-by-acidithiobacillus-thiooxidans
#19
Hugo Ramírez-Aldaba, Jorge Vazquez-Arenas, Fabiola S Sosa-Rodríguez, Donato Valdez-Pérez, Estela Ruiz-Baca, Jessica Viridiana García-Meza, Gabriel Trejo-Córdova, René H Lara
Biofilm formation and evolution are key factors to consider to better understand the kinetics of arsenopyrite biooxidation. Chemical and surface analyses were carried out using Raman spectroscopy, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), glow discharge spectroscopy (GDS), and protein analysis (i.e., quantification) in order to evaluate the formation of intermediate secondary compounds and any significant changes arising in the biofilm structure of Acidithiobacillus thiooxidans during a 120-h period of biooxidation...
July 12, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28674972/genetic-variation-and-phylogenetic-relationships-of-the-ectomycorrhizal-floccularia-luteovirens-on-the-qinghai-tibet-plateau
#20
Rui Xing, Qing-Bo Gao, Fa-Qi Zhang, Peng-Cheng Fu, Jiu-Li Wang, Hui-Ying Yan, Shi-Long Chen
Floccularia luteovirens, as an ectomycorrhizal fungus, is widely distributed in the Qinghai-Tibet Plateau. As an edible fungus, it is famous for its unique flavor. Former studies mainly focus on the chemical composition and genetic structure of this species. However, the phylogenetic relationship between genotypes remains unknown. In this study, the genetic variation and phylogenetic relationship between the genotypes of F. luteovirens in Qinghai-Tibet Plateau was estimated through the analysis on two protein-coding genes (rpb1 and ef-1α) from 398 individuals collected from 24 wild populations...
August 2017: Journal of Microbiology / the Microbiological Society of Korea
keyword
keyword
29344
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"