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https://www.readbyqxmd.com/read/27922096/enantiomer-signature-and-carbon-isotope-evidence-for-the-migration-and-transformation-of-ddts-in-arable-soils-across-china
#1
Lili Niu, Chao Xu, Siyu Zhu, Huiming Bao, Yang Xu, Hongyi Li, Zhijian Zhang, Xichang Zhang, Jiguo Qiu, Weiping Liu
Due to the adverse impact of DDTs on ecosystems and humans, a full fate assessment deems a comprehensive study on their occurrence in soils over a large region. Through a sampling campaign across China, we measured the concentrations, enantiomeric fractions (EFs), compound-specific carbon isotope composition of DDT and its metabolites, and the microbial community in related arable soils. The geographically total DDT concentrations are higher in eastern than western China. The EFs and δ(13)C of o,p'-DDT in soils from western China show smaller deviations from those of racemic/standard compound, indicating the DDT residues there mainly result from atmospheric transport...
December 6, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27921226/the-relationship-between-aerosol-particles-chemical-composition-and-optical-properties-to-identify-the-biomass-burning-contribution-to-fine-particles-concentration-a-case-study-for-s%C3%A3-o-paulo-city-brazil
#2
Regina Maura de Miranda, Fabio Lopes, Nilton Évora do Rosário, Marcia Akemi Yamasoe, Eduardo Landulfo, Maria de Fatima Andrade
The air quality in the Metropolitan Area of São Paulo (MASP) is primarily determined by the local pollution source contribution, mainly the vehicular fleet, but there is a concern about the role of remote sources to the fine mode particles (PM2.5) concentration and composition. One of the most important remote sources of atmospheric aerosol is the biomass burning emissions from São Paulo state's inland and from the central and north portions of Brazil. This study presents a synergy of different measurements of atmospheric aerosol chemistry and optical properties in the MASP in order to show how they can be used as a tool to identify particles from local and remote sources...
December 2016: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/27919535/occurrences-composition-profiles-and-source-identifications-of-polycyclic-aromatic-hydrocarbons-pahs-polybrominated-diphenyl-ethers-pbdes-and-polychlorinated-biphenyls-pcbs-in-ship-ballast-sediments
#3
Peng-Hao Su, Bao-Yi Lv, Gregg T Tomy, Jin-Xiang Xu, Wen Tian, Chun-Yan Hou, Fang Yin, Yi-Fan Li, Dao-Lun Feng
The aim of this study was to investigate the levels of persistent organic pollutants (POPs) including polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in ship ballast sediments. The ballast sediment samples were collected from six merchant ships docked in 2015 in Jiangyin City, China. Ballast sediments represent a potential vector for the transport of POPs and invasive species between marine environments. An attempt was also made to determine the sources of these compounds in the ballast sediment...
December 2, 2016: Chemosphere
https://www.readbyqxmd.com/read/27916493/free-amino-acid-concentrations-and-nitrogen-isotope-signatures-in-pinus-massoniana-lamb-needles-of-different-ages-for-indicating-atmospheric-nitrogen-deposition
#4
Yu Xu, Huayun Xiao
Free amino acid concentrations and nitrogen (N) isotopic composition in new current-year (new), mature current-year (middle-aged) and previous-year (old) Masson pine (Pinus massoniana Lamb.) needles were determined to indicate atmospheric N deposition in Guiyang (SW China). In different areas, free amino acids (especially arginine) concentrations in new and middle-aged needles were higher than in old needles, and the variation of free amino acids (especially arginine) concentrations in new and middle-aged needles was also greater than in old needles...
December 1, 2016: Environmental Pollution
https://www.readbyqxmd.com/read/27916309/optical-properties-of-secondary-organic-aerosols-derived-from-long-chain-alkanes-under-various-nox-and-seed-conditions
#5
Junling Li, Kun Li, Weigang Wang, Jing Wang, Chao Peng, Maofa Ge
Long-chain alkanes are a type of important intermediate-volatile organic compounds (IVOCs) in the atmosphere, which contribute to a large proportion of secondary organic aerosol (SOA). However, the optical properties of SOA derived from long-chain alkanes remain poorly understood. Here, we investigate the refractive index (RI) of SOA derived from photo-oxidation of dodecane (C12), pentadecane (C15) and heptadecane (C17) under low-NOx and high-NOx conditions with the absence or presence of inorganic aerosol seeds...
December 1, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27916303/seasonal-variation-of-particle-induced-oxidative-potential-of-airborne-particulate-matter-in-beijing
#6
Longyi Shao, Ying Hu, Rongrong Shen, Klaus Schäfer, Jing Wang, Jianying Wang, Jürgen Schnelle-Kreis, Ralf Zimmermann, Kelly BéruBé, Peter Suppan
An in vitro plasmid scission assay (PSA), the cell apoptosis assay, and ICP-MS were employed to study the oxidative potentials and trace element compositions of the airborne particulate matter (PM) in Beijing during a one year-long field campaign from June 2010 to June 2011. The cell damages induced by PM reveled by the cell apoptosis assay showed a similar variation pattern to the DNA damages obtained by PSA, verifying the feasibility of the PSA in analyzing the oxidative capacity of PM samples. The PSA experiments showed that the particle-induced DNA damage was highest in summer, followed by spring, winter and autumn in descending order...
December 1, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27913023/in-stream-metabolism-and-atmospheric-carbon-sequestration-in-a-groundwater-fed-karst-stream
#7
Junbing Pu, Jianhong Li, Mitra B Khadka, Jonathan B Martin, Tao Zhang, Shi Yu, Daoxian Yuan
Atmospheric carbon sequestered in karst systems through dissolution of carbonate minerals is considered to have no net effect on long-term regional and global carbon budgets because precipitation of dissolved carbonate minerals emits CO2 back to the atmosphere. Even though recent studies have implied that rapid kinetics of carbonate dissolution coupled with the aquatic photosynthetic uptake of dissolve inorganic carbon (DIC) could facilitate a stable atmospheric C sink in karst rivers and streams, little is known about the magnitudes and long-term stability of this C sink...
November 29, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27912912/passive-air-sampling-of-persistent-organic-pollutants-pops-and-emerging-compounds-in-kolkata-megacity-and-rural-mangrove-wetland-sundarban-in-india-an-approach-to-regional-monitoring
#8
Karla Pozo, Santosh Kumar Sarkar, Victor H Estellano, Soumita Mitra, Ondrej Audi, Petr Kukucka, Petra Přibylová, Jana Klánová, Simonetta Corsolini
Polyurethane foam (PUF) disk passive air samplers were deployed concurrently at five sites across Kolkata megacity and the rural mangrove wetland of Sundarban (UNESCO World Heritage Site) between January-March in 2014. Samples were analyzed for hexachlorocyclohexanes (HCHs), dichlorodiphenyltricholoroethanes (DDTs), polychlorinated biphenyls (PCBs) and, polybrominated diphenyl ethers (PBDEs) using gas chromatography and mass spectrometry (GC-MS). Derived air concentrations (pg/m(3)) for Kolkata ranged: for ∑α- and γ-HCH between 70 and 207 (114 ± 62), ∑6DDTs: 127-216 (161 ± 36), ∑7PCBs: 53-213 (141 ± 64), and ∑10PBDEs: 0...
November 29, 2016: Chemosphere
https://www.readbyqxmd.com/read/27911783/deglacial-temperature-history-of-west-antarctica
#9
Kurt M Cuffey, Gary D Clow, Eric J Steig, Christo Buizert, T J Fudge, Michelle Koutnik, Edwin D Waddington, Richard B Alley, Jeffrey P Severinghaus
The most recent glacial to interglacial transition constitutes a remarkable natural experiment for learning how Earth's climate responds to various forcings, including a rise in atmospheric CO2 This transition has left a direct thermal remnant in the polar ice sheets, where the exceptional purity and continual accumulation of ice permit analyses not possible in other settings. For Antarctica, the deglacial warming has previously been constrained only by the water isotopic composition in ice cores, without an absolute thermometric assessment of the isotopes' sensitivity to temperature...
November 28, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27911352/medical-equipment-antiseptic-processes-using-the-atmospheric-plasma-sprayed-copper-coatings
#10
M Goudarzi, Sh Saviz, M Ghoranneviss, A Salar Elahi
Antibacterial surfaces such as copper coatings are able to reduce the growth of bacteria. In this study, copper coatings was deposited on the 316 stainless steel substrates by a handmade device operating as an atmospheric plasma spraying system. The chemical composition microstructure and morphology surface of the coatings are examined by x-ray diffraction (XRD) and scanning electron microscope (SEM) and back scattering electron microscope (BSE). Micro hardness as one of the key properties of the coating is characterized based on cross-section...
November 30, 2016: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/27900624/the-sources-of-trace-element-pollution-of-dry-depositions-nearby-a-drinking-water-source
#11
Xinyue Guo, Hongbing Ji, Cai Li, Yang Gao, Huaijian Ding, Lei Tang, Jinguo Feng
Miyun Reservoir is one of the most important drinking water sources for Beijing. Thirteen atmospheric PM sampling sites were established around this reservoir to analyze the mineral composition, morphological characteristics, element concentration, and sources of atmospheric PM pollution, using transmission electron microscope, X-ray diffraction, and inductively coupled plasma mass spectrometry analyses. The average monthly dry deposition flux of aerosols was 15.18 g/m(2), with a range of 5.78-47.56 g/m(2)...
November 29, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27894769/identification-of-molecular-species-of-monoalkyldiacylglycerol-from-the-squid-berryteuthis-magister-using-liquid-chromatography-apci-high-resolution-mass-spectrometry
#12
Viacheslav G Rybin, Andrey B Imbs, Darja A Demidkova, Ekaterina V Ermolenko
Monoalkyldiacylglycerol (MADAG) is an important lipid class in mollusks, corals, starfishes, and some species of zooplankton. Up to 80% of liver oils of squids and sharks are comprised of MADAG. Except for one fish species, there are no data on the composition of MADAG molecular species of marine organisms. The molecular species of MADAG obtained from digestive glands of the deep-sea squid Berryteuthis magister were identified. High-performance liquid chromatography (HPLC) and tandem high-resolution mass spectrometry (HRMS) with atmospheric pressure chemical ionization (APCI) were applied...
November 25, 2016: Chemistry and Physics of Lipids
https://www.readbyqxmd.com/read/27894052/characterization-and-reactivity-of-iron-based-nanoparticles-synthesized-by-tea-extracts-under-various-atmospheres
#13
Jiewen Lin, Xiulan Weng, Rajarathnam Dharmarajan, Zuliang Chen
Bio-synthesis of Fe NPs in inert (nitrogen N-Fe NPs) and oxygen (O-Fe NPs) atmospheres employing green tea extracts was investigated through SEM, EDS, XPS and FT-IR techniques. The particle sizes of N-Fe NPs and O-Fe NPs were confirmed by SEM showing 84.7 ± 11.5 nm and 117.8 ± 26.2 nm respectively with subsequent evaluation of the percentage composition of Fe and O by EDS. The XPS results showed that the zero-valent iron and iron oxide nanoparticles were found to be dominant synthesized respectively in nitrogen and oxygen atmospheres...
November 25, 2016: Chemosphere
https://www.readbyqxmd.com/read/27889141/exploring-lot-to-lot-variation-in-spoilage-bacterial-communities-on-commercial-modified-atmosphere-packaged-beef
#14
Elina Säde, Katri Penttinen, Johanna Björkroth, Jenni Hultman
Understanding the factors influencing meat bacterial communities is important as these communities are largely responsible for meat spoilage. The composition and structure of a bacterial community on a high-O2 modified-atmosphere packaged beef product were examined after packaging, on the use-by date and two days after, to determine whether the communities at each stage were similar to those in samples taken from different production lots. Furthermore, we examined whether the taxa associated with product spoilage were distributed across production lots...
April 2017: Food Microbiology
https://www.readbyqxmd.com/read/27887825/national-investigation-of-semi-volatile-organic-compounds-pahs-ocps-and-pcbs-in-lake-sediments-of-china-occurrence-spatial-variation-and-risk-assessment
#15
Chaocan Li, Shouliang Huo, Zhiqiang Yu, Beidou Xi, Kevin M Yeager, Zhuoshi He, Chunzi Ma, Jingtian Zhang, Fengchang Wu
In this study, a large scale investigation of semi-volatile organic compounds (SVOCs) in sediments from 52 lakes, located in five geographic regions across China, was conducted to assess sediment quality in terms of organic contaminants. Concentrations of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs) in sediment were found to range between 17.00-6,633, 0.12-45.24, and 0.03-13.99ngg(-1), respectively. Lake sediments from different regions exhibited variation in contamination levels, and in the compositions of isomers...
November 22, 2016: Science of the Total Environment
https://www.readbyqxmd.com/read/27886655/gas-permeability-and-permselectivity-of-poly-l-lactic-acid-siox-film-and-its-application-in-equilibrium-modified-atmosphere-packaging-for-chilled-meat
#16
Tungalag Dong, Shuxin Song, Min Liang, Yu Wang, Xiaojing Qi, Yuqin Zhang, Xueyan Yun, Ye Jin
A layer of SiOx was deposited on the surface of poly(L-lactic acid) (PLLA) film to fabricate a PLLA/SiOx layered film, by plasma-enhanced chemical vapor deposition (PECVD) process. PLLA/SiOx film showed Young's modulus and tensile strength increased by 119.2% and 91.6%, respectively, over those of neat PLLA film. At 5 °C, the oxygen (O2 ) and carbon dioxide (CO2 ) permeability of PLLA/SiOx film decreased by 78.7% and 71.7%, respectively, and the CO2 /O2 permselectivity increased by 32.5%, compared to that of the neat PLLA film...
November 25, 2016: Journal of Food Science
https://www.readbyqxmd.com/read/27886563/nanomechanical-properties-wear-resistance-and-in-vitro-characterization-of-ta2o5-nanotubes-coating-on-biomedical-grade-ti-6al-4v
#17
Masoud Sarraf, Bushroa Abdul Razak, Bahman Nasiri-Tabrizi, Ali Dabbagh, Noor Hayaty Abu Kasim, Wan Jefrey Basirun, Eshamsul Bin Sulaiman
Tantalum pentoxide nanotubes (Ta2O5 NTs) can dramatically raise the biological functions of different kinds of cells, thus have promising applications in biomedical fields. In this study, Ta2O5 NTs were prepared on biomedical grade Ti-6Al-4V alloy (Ti64) via physical vapor deposition (PVD) and a successive two-step anodization in H2SO4: HF (99:1)+5% EG electrolyte at a constant potential of 15V. To improve the adhesion of nanotubular array coating on Ti64, heat treatment was carried out at 450°C for 1h under atmospheric pressure with a heating/cooling rate of 1°Cmin(-)(1)...
November 16, 2016: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/27886536/rare-earths-and-trace-elements-contents-in-leaves-a-new-indicator-of-the-composition-of-atmospheric-dust
#18
P Censi, F Cibella, E E Falcone, G Cuttitta, F Saiano, C Inguaggiato, V Latteo
The relationship between the trace element distribution in atmospheric particles and leaves of some exposed plants in the environment was recently demonstrated. This indication would suggest that the trace element analysis of leaves in these plants could provide information about the composition, nature and origin of the atmospheric dust dispersed in the environment. In order to corroborate this hypothesis, the distribution of trace elements and Rare Earths were studied in leaves of some endemic plants, in the atmospheric fallout and in soils of rural, urban and industrial ecosystems in Sicily...
November 22, 2016: Chemosphere
https://www.readbyqxmd.com/read/27881805/corrosion-resistance-and-biological-activity-of-tio2-implant-coatings-produced-in-oxygen-rich-environments
#19
Rui Zhang, Yi Wan, Xing Ai, Zhanqiang Liu, Dong Zhang
The physical and chemical properties of bio-titanium alloy implant surfaces play an important role in their corrosion resistance and biological activity. New turning and turning-rolling processes are presented, employing an oxygen-rich environment in order to obtain titanium dioxide layers that can both protect implants from corrosion and also promote cell adhesion. The surface topographies, surface roughnesses and chemical compositions of the sample surfaces were obtained using scanning electron microscopy, a white light interferometer, and the Auger electron spectroscopy, respectively...
November 23, 2016: Proceedings of the Institution of Mechanical Engineers. Part H, Journal of Engineering in Medicine
https://www.readbyqxmd.com/read/27881242/atmospheric-degradation-of-the-organothiophosphate-insecticide-pirimiphos-methyl
#20
Esther Borrás, Milagros Ródenas, Teresa Vera, Tatiana Gómez, Amalia Muñoz
The gas phase atmospheric degradation of pirimiphos-methyl (a widely used organophosphate insecticide and acaricide in many European regions) has been investigated at the large outdoor European Photoreactor (EUPHORE) in Valencia, Spain. Its photolysis has been studied under sunlight conditions and its reaction rate constant with OH radicals was measured by the relative rate method. The reaction with ozone was also investigated. The tropospheric degradation of pirimiphos-methyl is controlled mainly by the OH radical reaction...
November 21, 2016: Science of the Total Environment
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