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https://www.readbyqxmd.com/read/28431374/atmospheric-fallout-radionuclides-in-peatland-from-southern-poland
#1
Tomasz Mróz, Edyta Łokas, Justyna Kocurek, Michał Gąsiorek
Two peat profiles were collected in a peat bog located in Southern Poland and their geochronology were determined using (210)Pb, (238,239+240)Pu and (137)Cs radiometric techniques. The (210)Pb chronologies were established using the constant rate of supply model (CRS) and are in good agreement with the Pu isotopes and (137)Cs time markers. Maximum activities of Pu isotopes were found at a depth corresponding to the early 1960s, which is the period characterized by the maximum nuclear weapon tests. The results showed that the (210)Pb method is the most accurate technique for the determination age and accumulation rate of a peat...
April 18, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28430266/machine-learning-approach-to-oam-beam-demultiplexing-via-convolutional-neural-networks
#2
Timothy Doster, Abbie T Watnik
Orbital angular momentum (OAM) beams allow for increased channel capacity in free-space optical communication. Conventionally, these OAM beams are multiplexed together at a transmitter and then propagated through the atmosphere to a receiver where, due to their orthogonality properties, they are demultiplexed. We propose a technique to demultiplex these OAM-carrying beams by capturing an image of the unique multiplexing intensity pattern and training a convolutional neural network (CNN) as a classifier. This CNN-based demultiplexing method allows for simplicity of operation as alignment is unnecessary, orthogonality constraints are loosened, and costly optical hardware is not required...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430259/impact-of-assisting-atmospheric-pressure-plasma-on-the-formation-of-micro-and-nanoparticles-during-picosecond-laser-ablation-of-titanium
#3
Stefan Grottker, Wolfgang Viöl, Christoph Gerhard
In this work, we investigated the generation of particles during pure laser and plasma-assisted laser ablation of titanium. Experiments were performed using a NIR picosecond laser at a wavelength of 1030 nm and a pulse duration of 8 ps. For plasma-assisted ablation, an atmospheric pressure dielectric barrier discharge plasma was applied where the process gas was argon. Quantitative particle distributions at sizes from 10 nm to 10 μm were determined. In addition, we evaluated the amount of ablated material via laser scanning microscopy...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430223/data-processing-error-analysis-based-on-doppler-asymmetric-spatial-heterodyne-measurement
#4
Jing Shen, Wei Xiong, Hai-Liang Shi, Hai-Yan Luo, Zhi-Wei Li, Guang-Xiao Hu, Xue-Jing Fang
The Doppler asymmetric spatial heterodyne (DASH) interferometer provides the capability to retrieve wind speed in the upper atmosphere. The data processing leads to a significant retrieving error with the development of wind precision. The influence of window parameters on the isolated interferogram is analyzed theoretically. Based on the derivation, the system is established, and the interferogram with a small shift is sampled. The phase and wind speed are calculated under various window types and window width values...
April 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/28430189/warming-enhances-old-organic-carbon-decomposition-through-altering-functional-microbial-communities
#5
Lei Cheng, Naifang Zhang, Mengting Yuan, Jing Xiao, Yujia Qin, Ye Deng, Qichao Tu, Kai Xue, Joy D Van Nostrand, Liyou Wu, Zhili He, Xuhui Zhou, Mary Beth Leigh, Konstantinos T Konstantinidis, Edward Ag Schuur, Yiqi Luo, James M Tiedje, Jizhong Zhou
Soil organic matter (SOM) stocks contain nearly three times as much carbon (C) as the atmosphere and changes in soil C stocks may have a major impact on future atmospheric carbon dioxide concentrations and climate. Over the past two decades, much research has been devoted to examining the influence of warming on SOM decomposition in topsoil. Most SOM, however, is old and stored in subsoil. The fate of subsoil SOM under future warming remains highly uncertain. Here, by combining a long-term field warming experiment and a meta-analysis study, we showed that warming significantly increased SOM decomposition in subsoil...
April 21, 2017: ISME Journal
https://www.readbyqxmd.com/read/28430120/autonomous-multi-robot-search-for-a-hazardous-source-in-a-turbulent-environment
#6
Branko Ristic, Daniel Angley, Bill Moran, Jennifer L Palmer
Finding the source of an accidental or deliberate release of a toxic substance into the atmosphere is of great importance for national security. The paper presents a search algorithm for turbulent environments which falls into the class of cognitive (infotaxi) algorithms. Bayesian estimation of the source parameter vector is carried out using the Rao-Blackwell dimension-reduction method, while the robots are controlled autonomously to move in a scalable formation. Estimation and control are carried out in a centralised replicated fusion architecture assuming all-to-all communication...
April 21, 2017: Sensors
https://www.readbyqxmd.com/read/28429776/global-distribution-of-particle-phase-state-in-atmospheric-secondary-organic-aerosols
#7
Manabu Shiraiwa, Ying Li, Alexandra P Tsimpidi, Vlassis A Karydis, Thomas Berkemeier, Spyros N Pandis, Jos Lelieveld, Thomas Koop, Ulrich Pöschl
Secondary organic aerosols (SOA) are a large source of uncertainty in our current understanding of climate change and air pollution. The phase state of SOA is important for quantifying their effects on climate and air quality, but its global distribution is poorly characterized. We developed a method to estimate glass transition temperatures based on the molar mass and molecular O:C ratio of SOA components, and we used the global chemistry climate model EMAC with the organic aerosol module ORACLE to predict the phase state of atmospheric SOA...
April 21, 2017: Nature Communications
https://www.readbyqxmd.com/read/28429762/annealing-induced-re-crystallization-in-ch3nh3pbi3-xclx-for-high-performance-perovskite-solar-cells
#8
Yingguo Yang, Shanglei Feng, Meng Li, Weidong Xu, Guangzhi Yin, Zhaokui Wang, Baoquan Sun, Xingyu Gao
Using poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) as hole conductor, a series of inverted planar CH3NH3PbI3-xClx perovskite solar cells (PSCs) were fabricated based on perovskite annealed by an improved time-temperature dependent (TTD) procedure in a flowing nitrogen atmosphere for different time. Only after an optimum annealing time, an optimized power conversion efficiency of 14.36% could be achieved. To understand their performance dependence on annealing time, an in situ real-time synchrotron-based grazing incidence X-ray diffraction (GIXRD) was used to monitor a step-by-step gradual structure transformation from distinct mainly organic-inorganic hybrid materials into highly ordered CH3NH3PbI3 crystal during annealing...
April 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28429398/efficacy-of-passive-sampler-collection-for-atmospheric-no2-isotopes-under-simulated-environmental-conditions
#9
Justin G Coughlin, Zhongjie Yu, Emily M Elliott
RATIONALE: Nitrogen oxides or NOx (NOx  = NO + NO2 ) play an important role in air quality, atmospheric chemistry, and climate. The isotopic compositions of anthropogenic and natural NO2 sources are wide-ranging, and they can be used to constrain sources of ambient NO2 and associated atmospheric deposition of nitrogen compounds. While passive sample collection of NO2 isotopes has been used in field studies to determine NOx source influences on atmospheric deposition, this approach has not been evaluated for accuracy or precision under different environmental conditions...
April 20, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28429273/assessment-of-the-temporal-and-spatial-distribution-of-atmospheric-pcns-and-their-air-soil-exchange-using-passive-air-samplers-in-shanghai-east-china
#10
Qingqi Die, Zhiqiang Nie, Bo Yue, Xuemei Zhu, Xingbao Gao, Jianyuan Wang, Yufei Yang, Yanyan Fang, Qifei Huang
A total of 47 passive air samples and 25 soil samples were collected to study the temporal trend, distribution, and air-soil exchange of polychlorinated naphthalenes (PCNs) in Shanghai, China. Atmospheric PCNs ranged from 3.44 to 44.1 pg/m(3) (average of 21.9 pg/m(3)) in summer and 13.6 to 153 pg/m(3) (average of 40.0 pg/m(3)) in winter. In the soil samples, PCN concentrations were 54.7-1382 pg/g dry weight (average of 319 pg/g). Tri-CNs and tetra-CNs were two dominant homolog groups in air samples, while di-CNs were also found at comparable proportions to tri-CNs and tetra-CNs in soil samples...
April 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28429066/atmospheric-pressure-maldi-for-the-noninvasive-characterization-of-carbonaceous-ink-from-renaissance-documents
#11
Giuseppe Grasso, Marzia Calcagno, Alessandro Rapisarda, Roberta D'Agata, Giuseppe Spoto
The analytical methods that are usually applied to determine the compositions of inks from ancient manuscripts usually focus on inorganic components, as in the case of iron gall ink. In this work, we describe the use of atmospheric pressure/matrix-assisted laser desorption ionization-mass spectrometry (AP/MALDI-MS) as a spatially resolved analytical technique for the study of the organic carbonaceous components of inks used in handwritten parts of ancient books for the first time. Large polycyclic aromatic hydrocarbons (L-PAH) were identified in situ in the ink of XVII century handwritten documents...
April 21, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28428872/are-whooping-cranes-destined-for-extinction-climate-change-imperils-recruitment-and-population-growth
#12
Matthew J Butler, Kristine L Metzger, Grant M Harris
Identifying climatic drivers of an animal population's vital rates and locating where they operate steers conservation efforts to optimize species recovery. The population growth of endangered whooping cranes (Grus americana) hinges on juvenile recruitment. Therefore, we identify climatic drivers (solar activity [sunspots] and weather) of whooping crane recruitment throughout the species' life cycle (breeding, migration, wintering). Our method uses a repeated cross-validated absolute shrinkage and selection operator approach to identify drivers of recruitment...
April 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28427738/assessment-of-a-combined-dry-anaerobic-digestion-and-post-composting-treatment-facility-for-source-separated-organic-household-waste-using-material-and-substance-flow-analysis-and-life-cycle-inventory
#13
Morten Bang Jensen, Jacob Møller, Charlotte Scheutz
The fate of total solids, volatile solids, total organic carbon, fossil carbon, biogenic carbon and 17 substances (As, Ca, CaCO3, Cd, Cl, Cr, Cu, H, Hg, K, Mg, N, Ni, O, P, Pb, S, Zn) in a combined dry anaerobic digestion and post-composting facility were assessed. Mass balances showed good results with low uncertainties for non-volatile substances, while balances for nitrogen, carbon, volatile solids and total organic carbon showed larger but reasonable uncertainties, due to volatilisation and emissions into the air...
April 17, 2017: Waste Management
https://www.readbyqxmd.com/read/28427674/sonochemical-synthesis-and-characterization-of-new-nanostructures-cobalt-ii-metal-organic-complexes-derived-from-the-azo-coupling-reaction-of-4-amino-benzoic-acid-with-anthranilic-acid-salicylaldehyde-and-2-naphtol
#14
Xiao-Xue Cheng, Shiva Hojaghani, Mao-Lin Hu, Moayed Hosaini Sadr, Ali Morsali
Nanostructures of three new cobalt(II) complexes, (CoL1)·0.5DMF·1.5MeOH (1), [H2L1=5-(4-Carboxy phenyl azo) anthranilic acid], (Co(L2)2)·1.5MeOH (2), [HL2=5-(4-Carboxy phenyl azo) salicylaldehyde] and (Co(L3)2)·0.5DMF·0.5MeOH (3), [HL3=1-(4-Carboxy phenyl azo) 2-naphtol], have been synthesized by the reaction of H2L1, HL2 and HL3 with Co(OAc)2·4H2O through sonochemical process. Calcination of the nano-sized compounds 1-3 yield Co3O4 nanoparticles at 450°C under air atmosphere. These nanostructures were characterized by X-ray powder diffraction (XRD) and Scanning Electron Microscopy (SEM)...
July 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28427636/ultrasound-assisted-synthesis-of-nano-structured-zinc-ii-based-metal-organic-frameworks-as-precursors-for-the-synthesis-of-zno-nano-structures
#15
Fahime Bigdeli, Hosein Ghasempour, Alireza Azhdari Tehrani, Ali Morsali, Hassan Hosseini-Monfared
A 3D, porous Zn(II)-based metal-organic framework {[Zn2(oba)2(4-bpmn)]·(DMF)1.5}n (TMU-21), (4-bpmn=N,N'-Bis-pyridin-4-ylmethylene-naphtalene-1,5-diamine, H2oba=4,4'-oxybis(benzoic acid)) with nano-rods morphology under ultrasonic irradiation at ambient temperature and atmospheric pressure was prepared and characterized by scanning electron microscopy. Sonication time and concentration of initial reagents effects on the size and morphology of nano-structured MOFs were studied. Also {[Zn2(oba)2(4-bpmn)] (TMU-21) and {[Zn2(oba)2(4-bpmb)] (TMU-6), 4-bpmb=N,N'-(1,4-phenylene)bis(1-(pyridin-4-yl)methanimine) were easily prepared by mechanochemical synthesis...
July 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28427624/ultrasound-assisted-biodiesel-production-by-a-novel-composite-of-fe-iii-based-mof-and-phosphotangestic-acid-as-efficient-and-reusable-catalyst
#16
Ahmad Nikseresht, Asra Daniyali, Mahdi Ali-Mohammadi, Ahmad Afzalinia, Abbas Mirzaie
In this work, esterification of oleic acid by various alcohols is achieved with high yields under ultrasonic irradiation. This reaction performed with a novel heterogeneous catalyst that fabricated by heteropoly acid and Fe(III)-based MOF, namely MIL-53 (Fe). Syntheses of MIL-53 and encapsulation process carry out by ultrasound irradiation at ambient temperature and atmospheric pressure. The prepared composite was characterized by various techniques such as XRD, FT-IR, SEM, BET and ICP that demonstrate excellent catalytic activities, while being highly convenient to synthesize...
July 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28427297/the-effect-of-moisture-content-within-multilayer-protective-clothing-on-protection-from-radiation-and-steam
#17
Yun Su, Jun Li, Guowen Song
The moisture from skin sweat and atmospheric water affects thermal protective performance provided by multilayer protective clothing. Four levels of moisture content were selected to evaluate the impact of moisture on thermal protection under dry (thermal radiation) and wet (thermal radiation and low-pressure steam) heat exposure. Also, the role of moisture and its relationship with exposure time were analyzed based on skin heat flux and Henriques integral value. It was found that the addition of moisture to a fabric system results in differences in second---- and third-degree skin burn times...
April 21, 2017: International Journal of Occupational Safety and Ergonomics: JOSE
https://www.readbyqxmd.com/read/28426381/hyperbaric-oxygen-for-experimental-intracerebral-haemorrhage-systematic-review-and-stratified-meta-analysis
#18
Han-Jin Cui, Hao-Yu He, A-Li Yang, Hua-Jun Zhou, Tao Tang, Jie-Kun Luo
OBJECTIVE: Hyperbaric oxygen (HBO) is widely used in treating various neurological diseases. However, HBO for treatment of intracerebral haemorrhage (ICH) remains controversial, in either animal or clinical studies. Therefore, we conducted this systematic review and meta-analysis on studies describing the efficacy of HBO in animal models of ICH. METHODS: Studies were identified by searching mainstream databases through November 2015. The efficacy of HBO in animal models of ICH was assessed by changes in the brain water content (BWC), neurobehavioural outcome (NO) or both...
2017: Brain Injury: [BI]
https://www.readbyqxmd.com/read/28426293/identifying-thermal-breakdown-products-of-thermoplastics
#19
Marianne Guillemot, Benoît Oury, Sandrine Melin
Polymers processed to produce plastic articles are subjected to temperatures between 150°C and 450°C or more during overheated processing and breakdowns. Heat-based processing of this nature can lead to emission of volatile organic compounds (VOCs) into the thermoplastic processing shop. In this study, laboratory experiments, qualitative and quantitative emissions measurement in thermoplastic factories were carried out. The first step was to identify the compounds released depending on the thermoplastic nature, the temperature and the type of process...
April 20, 2017: Journal of Occupational and Environmental Hygiene
https://www.readbyqxmd.com/read/28426222/structural-and-dynamical-properties-of-tetra-alkyl-ammonium-bromide-aqueous-solutions-a-molecular-dynamics-simulation-study-using-a-polarizable-force-field
#20
Dengpan Dong, Justin B Hooper, Dmitry Bedrov
Understanding the behavior of aqueous solutions containing tetra-alkyl ammonium (TAA) cations is of great significance in a number of applications, including polymer membranes for fuel cells. In this work, a polarizable force field has been used to preform atomistic molecular dynamics (MD) simulations of aqueous solutions containing tetra-methyl ammonium (TMA) or tetra-butyl ammonium (TBA) cations and Br counterions. Extensive MD simulations of TMA-Br/water and TBA-Br/water systems were conducted as a function of solution composition (ion pair : water molar ratios of 1:10, 1:20, 1:30, 1:63, 1:500) at atmospheric pressure and 298K...
April 20, 2017: Journal of Physical Chemistry. B
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