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https://www.readbyqxmd.com/read/28525285/development-of-plasmonic-cu2o-cu-composite-arrays-as-visible-and-near-infrared-light-driven-plasmonic-photocatalysts
#1
Kosuke Sugawa, Natsumi Tsunenari, Hideyuki Takeda, Saki Fujiwara, Tsuyoshi Akiyama, Jotaro Honda, Shuto Igari, Kyo Tokuda, Naoto Takeshima, Yasuhiro Watanuki, Satoshi Tsukahara, Kouichi Takase, Tetsuo Umegaki, Yoshiyuki Kojima, Nobuyuki Nishimiya, Nobuko Fukuda, Yasuyuki Kusaka, Hirobumi Ushijima, Joe Otsuki
We describe efficient visible- and near-infrared (Vis/NIR) light-driven photocatalytic properties of hybrids of Cu2O and plasmonic Cu arrays. The Cu2O/Cu arrays were prepared simply by allowing to stand a Cu half-shell array in oxygen atmosphere for 3 h, which were prepared by depositing Cu on two-dimensional colloidal crystals with diameters of 543 or 224 nm. The localized surface plasmon resonances (LSPRs) of the arrays were strongly excited at 866 and 626 nm, respectively at which the imaginary part of the dielectric function of Cu is small...
May 19, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28520196/environmentally-friendly-recycling-of-fuel-cell-s-membrane-electrode-assembly-using-ionic-liquids
#2
Sophie Legeai, Maxime Balva, Nathalie Leclerc, Emmanuel Billy, Eric Meux
The platinum nanoparticles used as catalyst in Proton Exchange Membrane Fuel Cells (PEMFCs) could represent around 46 % of the total price of the cells1 for a large scale production which is one of the limitation of their commercialization. The recycling of this platinum catalyst can then be the best alternative to limit the production cost of PEMFCs. Usual recovery routes for spent catalysts containing platinum are pyro-hydrometallurgical processes in which a calcination step is followed by aqua regia treatment, generating fumes and NOx emission, respectively...
May 18, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28516958/the-origin-and-degassing-history-of-the-earth-s-atmosphere-revealed-by-archean-xenon
#3
Guillaume Avice, Bernard Marty, Ray Burgess
Xenon (Xe) is an exceptional tracer for investigating the origin and fate of volatile elements on Earth. The initial isotopic composition of atmospheric Xe remains unknown, as do the mechanisms involved in its depletion and isotopic fractionation compared with other reservoirs in the solar system. Here we present high precision analyses of noble gases trapped in fluid inclusions of Archean quartz (Barberton, South Africa) that reveal the isotopic composition of the paleo-atmosphere at ≈3.3 Ga. The Archean atmospheric Xe is mass-dependently fractionated by 12...
May 18, 2017: Nature Communications
https://www.readbyqxmd.com/read/28516763/first-assessment-of-nox-sources-at-a-regional-background-site-in-north-china-using-isotopic-analysis-linked-with-modeling
#4
Zheng Zong, Xiaoping Wang, Chongguo Tian, Yingjun Chen, Yunting Fang, Fan Zhang, Cheng Li, Jianzhong Sun, Jun Li, Gan Zhang
Nitrogen oxides (NOx, including NO and NO2) play an important role in the formation of atmospheric particles. Thus, NOx emission reduction is critical for improving air quality, especially in severely air-polluted regions (e.g., North China). In this study, the source of NOx was investigated by the isotopic composition (δ15N) of particulate nitrate (p-NO3-) at Beihuangcheng Island (BH), a regional background site in North China. It was found that the δ15N-NO3- (n = 120) values varied between -1.7 and +24...
May 18, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28514080/methane-emission-from-feather-moss-stands
#5
Dheeraj Kanaparthi, Andreas Reim, Guntars O Martinson, Bianca Pommerenke, Ralf Conrad
Data from remote sensing and Eddy towers indicate that forests are not always net sinks for atmospheric CH4 . However, studies describing specific sources within forests and functional analysis of microorganisms on sites with CH4 turnover are scarce. Feather moss stands were considered to be net sinks for carbon dioxide, but received little attention to their role in CH4 cycling. Therefore, we investigated methanogenic rates and pathways together with the methanogenic microbial community composition in feather moss stands from temperate and boreal forests...
May 17, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28514052/shift-in-community-structure-in-an-early-successional-mediterranean-shrubland-driven-by-long-term-experimental-warming-and-drought-and-natural-extreme-droughts
#6
Daijun Liu, Marc Estiarte, Romà Ogaya, Xiaohong Yang, Josep Peñuelas
Global warming and recurring drought are expected to accelerate water limitation for plant communities in semiarid Mediterranean ecosystems and produce directional shifts in structure and composition that are not easily detected, and supporting evidence is scarce. We conducted a long-term (17 years) nocturnal-warming (+0.6 °C) and drought (-40% rainfall) experiment in an early-successional Mediterranean shrubland to study the changes in community structure and composition, contrasting functional groups and dominant species, and the superimposed effects of natural extreme drought...
May 17, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28513752/comparison-of-pm2-5-carbonaceous-pollutants-between-an-urban-site-in-shanghai-and-a-background-site-in-a-coastal-east-china-sea-island-in-summer-concentration-composition-and-sources
#7
Fengwen Wang, Tian Lin, Yuanyuan Li, Zhigang Guo, Neil L Rose
Nine paired samples of atmospheric particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM2.5) were collected concurrently from an urban site in Shanghai, China and a background site in Huaniao Island (HNI) in the coastal East China Sea (ECS) between July 21 and 29, 2011. The samples were analyzed for 16 United States Environmental Protection Agency (USEPA) priority polycyclic aromatic hydrocarbons (PAHs), n-alkanes (20 species, C14-C33), hopanes (10 species, C29-C32), and steranes (12 species, C27-C29)...
May 17, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28508428/characterization-and-quantitation-of-pvp-content-in-a-silicone-hydrogel-contact-lens-produced-by-dual-phase-polymerization-processing
#8
Andrew J Hoteling, William F Nichols, Patricia S Harmon, Shawn M Conlon, Ivan M Nuñez, Joseph Hoff, Orlando M Cabarcos, Robert B Steffen, Daniel J Hook
Polyvinylpyrrolidone (PVP) has been incorporated over the years into numerous hydrogel contact lenses as both a primary matrix component and an internal wetting agent to increase lens wettability. In this study, complementary analytical techniques were used to characterize the PVP wetting agent component of senofilcon A and samfilcon A contact lenses, both in terms of chemical composition and amount present. Photo-differential scanning calorimetry (photo-DSC), gas chromatography with a flame ionization detector (GC-FID), and high-resolution/accurate mass (HR/AM) liquid chromatography-mass spectrometry (LC-MS) techniques confirmed dual phase reaction and curing of the samfilcon A silicone hydrogel material...
May 15, 2017: Journal of Biomedical Materials Research. Part B, Applied Biomaterials
https://www.readbyqxmd.com/read/28505434/photolysis-of-particulate-nitrate-as-a-source-of-hono-and-nox
#9
Chunxiang Ye, Ning Zhang, Honglian Gao, Xianliang Zhou
Photolysis of nitric acid on the surface has been found recently to be greatly enhanced from that in the gas phase. Yet, photolysis of particulate nitrate (pNO3) associated with atmospheric aerosols is still relatively unknown. Here, aerosol filter samples were collected both near the ground surface and throughout the troposphere on board NSF/NACR C-130 aircraft. The photolysis rate constants of pNO3 were determined from these samples by directly monitoring the production rates of nitrous acid (HONO) and nitrogen dioxide (NO2) under UV light (> 290 nm) irradiation...
May 15, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28501149/novel-cellulose-based-halochromic-test-strips-for-naked-eye-detection-of-alkaline-vapors-and-analytes
#10
Hussein Abou-Yousef, Tawfik A Khattab, Yehia A Youssef, Naser Al-Balakocy, Samir Kamel
A simple, portable and highly sensitive naked-eye test strip is successfully prepared for optical detection of gaseous and aqueous alkaline analytes. Novel pH-sensory tricyanofuran-hydrazone (TCFH) disperse colorant containing a hydrazone recognition functional moiety is successfully synthesized via azo-coupling reaction between active methyl-containing tricyanofuran (TCF) heterocycle and diazonium salt of 4-aminobenzaldehyde followed by Knoevenagel condensation with malononitrile. UV-vis absorption spectra display solvatochromism and reversible color changes of the TCFH solution in dimethyl sulfoxide in response to pH variations...
August 1, 2017: Talanta
https://www.readbyqxmd.com/read/28501016/role-of-climate-anomalies-on-decadal-variation-in-the-occurrence-of-wintertime-haze-in-the-yangtze-river-delta-china
#11
Jianming Xu, Luyu Chang, Fengxia Yan, JinHai He
The wintertime haze day (HD) in the Yangtze River Delta (YRD) region of China shows a significant upward trend during the past decades due to the rapid industrialization and urbanization. Besides the enhanced anthropogenic emission, climate change also plays the important role in the long term HD variations. In this study, the significant decadal variation of wintertime HD during the period 1960-2012 in YRD is examined by the empirical orthogonal function (EOF) analysis, featured as less HD occurrence before 1980 and more occurrence after 2000...
May 10, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28500915/a-comparison-of-denitrifying-bacterial-community-structures-and-abundance-in-acidic-soils-between-natural-forest-and-re-vegetated-forest-of-nanling-nature-reserve-in-southern-china
#12
Han Meng, Ruonan Wu, Yong-Feng Wang, Ji-Dong Gu
Denitrification plays a key role in converting reactive nitrogen species to dinitrogen gas back into the atmosphere to maintain the equilibrium of nitrogen cycling in ecosystems. In this study, functional genes of nirK and nosZ were used to detect the community structure and abundance of denitrifying microorganisms in acidic forest soils in southern China. Three sets of factors were considered for a comparison among 5 forests, including forest types (natural vs. re-vegetated), depths (surface layer vs. lower layer) and seasons (winter vs...
May 10, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28500553/characterization-of-rainwater-chemical-composition-after-a-southeast-asia-haze-event-insight-of-transboundary-pollutant-transport-during-the-northeast-monsoon
#13
Mohd Shahrul Mohd Nadzir, Chin Yik Lin, Md Firoz Khan, Mohd Talib Latif, Doreena Dominick, Haris Hafizal Abdul Hamid, Noorlin Mohamad, Khairul Nizam Abdul Maulud, Muhammad Ikram Abdul Wahab, Nurul Farahana Kamaludin, Mohamad Azwani Shah Mat Lazim
Open biomass burning in Peninsula Malaysia, Sumatra, and parts of the Indochinese region is a major source of transboundary haze pollution in the Southeast Asia. To study the influence of haze on rainwater chemistry, a short-term investigation was carried out during the occurrence of a severe haze episode from March to April 2014. Rainwater samples were collected after a prolonged drought and analyzed for heavy metals and major ion concentrations using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively...
May 13, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28499261/structural-signatures-of-water-soluble-organic-aerosols-in-contrasting-environments-in-south-america-and-western-europe
#14
Regina M B O Duarte, João T V Matos, Andreia S Paula, Sónia P Lopes, Guilherme Pereira, Pérola Vasconcellos, Adriana Gioda, Renato Carreira, Artur M S Silva, Armando C Duarte, Patricia Smichowski, Nestor Rojas, Odon Sanchez-Ccoyllo
This study describes and compares the key structural units present in water-soluble organic carbon (WSOC) fraction of atmospheric aerosols collected in different South American (Colombia - Medellín and Bogotá, Peru - Lima, Argentina - Buenos Aires, and Brazil - Rio de Janeiro, São Paulo, and Porto Velho, during moderate (MBB) and intense (IBB) biomass burning) and Western European (Portugal - Aveiro and Lisbon) locations. Proton nuclear magnetic resonance ((1)H NMR) spectroscopy was employed to assess the relative distribution of non-exchangeable proton functional groups in aerosol WSOC of diverse origin, for the first time to the authors' knowledge in South America...
May 9, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28498657/surface-enhanced-raman-spectroscopy-a-facile-and-rapid-method-for-the-chemical-components-study-of-individual-atmospheric-aerosol
#15
Yu Fu, Christian Kuppe, Ventsislav Kolev Valev, Hongbo Fu, Liwu Zhang, Jianmin Chen
A simple and rapid method for detecting chemical components of individual aerosol particles on Klarite substrate with surface-enhanced Raman spectroscopy (SERS) is described. For both single simulated aerosol particles and ambient atmospheric particles, this new analytical method promotes the enhancement factor of the Raman signal. The spectra of ammonium sulfate and naphthalene particles at the microscopic level are enhanced by a factor of 6 and therefore greatly improve the detection of the chemical composition of an individual aerosol particle...
May 12, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28497883/laser-induced-graphene-in-controlled-atmospheres-from-superhydrophilic-to-superhydrophobic-surfaces
#16
Yilun Li, Duy Xuan Luong, Jibo Zhang, Yash R Tarkunde, Carter Kittrell, Franklin Sargunaraj, Yongsung Ji, Christopher J Arnusch, James M Tour
The modification of graphene-based materials is an important topic in the field of materials research. This study aims to expand the range of properties for laser-induced graphene (LIG), specifically to tune the hydrophobicity and hydrophilicity of the LIG surfaces. While LIG is normally prepared in the air, here, using selected gas atmospheres, a large change in the water contact angle on the as-prepared LIG surfaces has been observed, from 0° (superhydrophilic) when using O2 or air, to >150° (superhydrophobic) when using Ar or H2 ...
May 12, 2017: Advanced Materials
https://www.readbyqxmd.com/read/28495968/laboratory-measurements-of-hdo-h2o-isotopic-fractionation-during-ice-deposition-in-simulated-cirrus-clouds
#17
Kara D Lamb, Benjamin W Clouser, Maximilien Bolot, Laszlo Sarkozy, Volker Ebert, Harald Saathoff, Ottmar Möhler, Elisabeth J Moyer
The stable isotopologues of water have been used in atmospheric and climate studies for over 50 years, because their strong temperature-dependent preferential condensation makes them useful diagnostics of the hydrological cycle. However, the degree of preferential condensation between vapor and ice has never been directly measured at temperatures below 233 K (-40 °C), conditions necessary to form cirrus clouds in the Earth's atmosphere, routinely observed in polar regions, and typical for the near-surface atmospheric layers of Mars...
May 11, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28495096/sequential-extraction-protocol-for-organic-matter-from-soils-and-sediments-using-high-resolution-mass-spectrometry
#18
Malak M Tfaily, Rosalie K Chu, Jason Toyoda, Nikola Tolić, Errol W Robinson, Ljiljana Paša-Tolić, Nancy J Hess
A vast number of organic compounds are present in soil organic matter (SOM) and play an important role in the terrestrial carbon cycle, facilitate interactions between organisms, and represent a sink for atmospheric CO2. The diversity of different SOM compounds and their molecular characteristics is a function of the organic source material and biogeochemical history. By understanding how SOM composition changes with sources and the processes by which it is biogeochemically altered in different terrestrial ecosystems, it may be possible to predict nutrient and carbon cycling, response to system perturbations, and impact of climate change will have on SOM composition...
June 15, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28494290/importance-of-aerosol-non-sphericity-in-estimating-aerosol-radiative-forcing-in-indo-gangetic-basin
#19
Parul Srivastava, Sagnik Dey, Atul Kumar Srivastava, Sachchidanand Singh, S K Mishra, Suresh Tiwari
Aerosols are usually presumed spherical in shape while estimating the direct radiative forcing (DRF) using observations or in the models. In the Indo-Gangetic Basin (IGB), a regional aerosol hotspot where dust is a major aerosol species and has been observed to be non-spherical in shape, it is important to test the validity of this assumption. We address this issue using measured chemical composition at megacity Delhi, a representative site of the western IGB. Based on the observation, we choose three non-spherical shapes - spheroid, cylinder and chebyshev, and compute their optical properties...
May 8, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28493428/optical-thermal-and-mechanical-characterization-of-ga2-se3-added-gls-glass
#20
Andrea Ravagli, Christopher Craig, Ghada A Alzaidy, Paul Bastock, Daniel W Hewak
Gallium lanthanum sulfide glass (GLS) has been widely studied in the last 40 years for middle-infrared applications. In this work, the results of the substitution of selenium for sulphur in GLS glass are described. The samples are prepared via melt-quench method in an argon-purged atmosphere. A wide range of compositional substitutions are studied to define the glass-forming region of the modified material. The complete substitution of Ga2 S3 by Ga2 Se3 is achieved by involving new higher quenching rate techniques compared to those containing only sulfides...
May 11, 2017: Advanced Materials
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