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Carbon dating

Miao Zhang, Heinz Frei
Water oxidation is an essential reaction of an artificial photosystem for solar fuel generation because it provides electrons needed to reduce carbon dioxide or protons to a fuel. Earth-abundant metal oxides are among the most attractive catalytic materials for this reaction because of their robustness and scalability, but their efficiency poses a challenge. Knowledge of catalytic surface intermediates gained by vibrational spectroscopy under reaction conditions plays a key role in uncovering kinetic bottlenecks and provides a basis for catalyst design improvements...
February 22, 2017: Annual Review of Physical Chemistry
Feng Li, Hong Wang, Dominik Kufer, Liangliang Liang, Weili Yu, Erkki Alarousu, Chun Ma, Yangyang Li, Zhixiong Liu, Changxu Liu, Nini Wei, Fei Wang, Lang Chen, Omar F Mohammed, Andrea Fratalocchi, Xiaogang Liu, Gerasimos Konstantatos, Tom Wu
Organolead trihalide perovskites have drawn substantial interest for photovoltaic and optoelectronic applications due to their remarkable physical properties and low processing cost. However, perovskite thin films suffer from low carrier mobility as a result of their structural imperfections such as grain boundaries and pinholes, limiting their device performance and application potential. Here we demonstrate a simple and straightforward synthetic strategy based on coupling perovskite films with embedded single-walled carbon nanotubes...
February 22, 2017: Advanced Materials
Liangxiao Tan, Bien Tan
Hypercrosslinked polymers (HCPs) are a series of permanent microporous polymer materials initially reported by Davankov, and have received an increasing level of research interest. In recent years, HCPs have experienced rapid growth due to their remarkable advantages such as diverse synthetic methods, easy functionalization, high surface area, low cost reagents and mild operating conditions. Judicious selection of monomers, appropriate length crosslinkers and optimized reaction conditions yielded a well-developed polymer framework with an adjusted porous topology...
February 22, 2017: Chemical Society Reviews
Annette Kainu, Jyri Toikka, Esko Vanninen, Kirsi L Timonen
Measurement standards for pulmonary diffusing capacity were updated in 2005 by the ATS/ERS Task Force. However, in Finland reference values published in 1982 by Viljanen et al. have been used to date. The main aim of this study was to produce updated reference models for single-breath diffusing capacity for carbon monoxide for Finnish adults. Single-breath diffusing capacity for carbon monoxide was measured in 631 healthy non-smoking volunteers (41.5% male). Reference values for diffusing capacity (DLCO), alveolar volume (VA), diffusing capacity per unit of lung volume (DLCO/VA), and lung volumes were calculated using a linear regression model...
April 2017: Scandinavian Journal of Clinical and Laboratory Investigation
E Heggen, M Svendsen, S Tonstad
BACKGROUND AND AIM: Weight gain after stopping smoking potentially counteracts improvements in cardiometabolic risks. We investigated changes in metabolic syndrome (MetS) components and homeostasis assessment model insulin resistance (HOMA-IR) in smokers given dietary counseling during their quit attempt. METHODS AND RESULTS: Smokers (≥10 cigarettes/day) with BMI 25-40 kg/m(2) were randomized to a low-carbohydrate or low-fat diet and treated with a standard course of varenicline for 12 weeks...
January 4, 2017: Nutrition, Metabolism, and Cardiovascular Diseases: NMCD
Rong Mao, Si-Yue Li, Xin-Hou Zhang, Xian-Wei Wang, Chang-Chun Song
Understanding how P enrichment alters the quantity and quality of dissolved organic carbon (DOC) is important, because of their role in regulating the C cycle. Here, we established a four-level P addition experiment (0, 1.2, 4.8, and 9.6gPm(-2)year(-1)) in a N-limited freshwater wetland in the Sanjiang Plain, Northeast China. The aim of this study was to examine the effects of eight years of P addition on DOC concentration, SUVA254 (Abs(254)/DOC concentration, indicating the aromaticity of DOC), C:C ratio (Abs(400)/DOC concentration, indicating the proportion of colored humic substances in DOC), and E4:E6 ratio (Abs(465)/Abs(665), indicating the molecular size of humic substances) in surface water and soil pore water (0-15cm depth) during the growing season (June through September)...
February 16, 2017: Science of the Total Environment
Hao-Chun Hu, Shu-Yi Lin, Yi-Ting Hung, Shyue-Yih Chang
Importance: There are few reports evaluating awake, office-based carbon dioxide (CO2) laser surgery for laryngeal lesions. To date, this study was the largest reported case series of office-based laryngeal surgery by fiber delivery CO2 laser. Office-based laryngeal surgical procedures have become increasingly popular. Technical problems and treatment outcomes associated with the use of a CO2 laser for office-based laryngeal surgery have yet to be fully addressed. Objectives: To discuss a single institution's clinical experience with office-based CO2 laser laryngeal surgery and the feasibility and limitations associated with this procedure...
February 16, 2017: JAMA Otolaryngology—Head & Neck Surgery
Souvik Roy, Bhaskar Sharma, Jacques Pecaut, Philippe Simon, Marc Fontecave, Phong D Tran, Etienne Derat, Vincent Artero
We report here on a new series of CO2-reducing molecular catalysts based on Earth-abundant elements that are very selective for the production of acid formic in DMF/water mixtures (Faradaic efficiency of 90±10%) at moderate overpotentials (500-700 mV in DMF measured at the middle of the catalytic wave). The [CpCo(PR2NR'2)I]+compounds contain diphosphine ligands PR2NR'2 with two pendent amine residues that act as proton relays during CO2 reduction catalysis and tune their activity. Four different PR2NR'2 ligands with cyclohexyl or phenyl substituents on phosphorus and benzyl or phenyl substituents on nitrogen were employed and the compound with the most electron-donating phosphine ligand and the most basic amine functions performs best among the series with turnover frequency >1000 s 1...
February 16, 2017: Journal of the American Chemical Society
J Galindo-de-la-Rosa, N Arjona, A Moreno-Zuria, E Ortiz-Ortega, M Guerra-Balcázar, J Ledesma-García, L G Arriaga
The purpose of this work is to evaluate single and double-cell membraneless microfluidic fuel cells (MMFCs) that operate in the presence of simulated body fluids SBF, human serum and blood enriched with ethanol as fuels. The study was performed using the alcohol dehydrogenase enzyme immobilised by covalent binding through an array composed of carbon Toray paper as support and a layer of poly(methylene blue)/tetrabutylammonium bromide/Nafion and glutaraldehyde (3D bioanode electrode). The single MMFC was tested in a hybrid microfluidic fuel cell using Pt/C as the cathode...
February 8, 2017: Biosensors & Bioelectronics
Shunsuke Adachi, Kazuaki Yoshikawa, Utako Yamanouchi, Takanari Tanabata, Jian Sun, Taiichiro Ookawa, Toshio Yamamoto, Rowan F Sage, Tadashi Hirasawa, Junichi Yonemaru
Increasing the rate of leaf photosynthesis is one important approach for increasing grain yield in rice (Oryza sativa). Exploiting the natural variation in CO2 assimilation rate (A) between rice cultivars using quantitative genetics is one promising means to identify genes contributing to higher photosynthesis. In this study, we determined precise location of Carbon Assimilation Rate 8 (CAR8) by crossing a high-yielding indica cultivar with a Japanese commercial cultivar. Fine mapping suggested that CAR8 encodes a putative Heme Activator Protein 3 (OsHAP3) subunit of a CCAAT-box-binding transcription factor called OsHAP3H...
2017: Frontiers in Plant Science
Teeba M Darweesh, Muthanna J Ahmed
Granular activated carbon (KAC) was prepared from abundant Phoenix dactylifera L. stones by microwave- assisted KOH activation. The characteristics of KAC were tested by pore analyses, scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). The adsorption behavior of levofloxacin (LEV) antibiotic on KAC with surface area of 817m(2)/g and pore volume of 0.638cm(3)/g were analyzed using batch and fixed bed systems. The equilibrium data collected by batch experiments were well fitted with Langmuir compared to Freundlich and Temkin isotherms...
February 5, 2017: Environmental Toxicology and Pharmacology
M Walker, H Theaker, R Yaman, D Poggio, W Nimmo, A Bywater, G Blanch, M Pourkashanian
This paper describes the analysis of an AD plant that is novel in that it is located in an urban environment, built on a micro-scale, fed on food and catering waste, and operates as a purposeful system. The plant was built in 2013 and continues to operate to date, processing urban food waste and generating biogas for use in a community café. The plant was monitored for a period of 319days during 2014, during which the operational parameters, biological stability and energy requirements of the plant were assessed...
February 6, 2017: Waste Management
Raheel Anjum, Jinzhang Gao, Qiang Tang, Xiubin He, Xinbao Zhang, Yi Long, Zhonglin Shi, Mingfeng Wang
The influences of total organic carbon (TOC) and total nitrogen (TN) on Lead-210 ((210)Pb) dating have recently been of increasing concern in lacustrine research. Sediment core from Changshou Lake in the Longxi catchment was investigated for influence of TOC on (210)Pb dating. Lead-210 excess ((210)Pbex), Cesium-137 ((137)Cs) activities, TOC, TN, and particle size were measured. We proposed a dating index based on (137)Cs chronology and particle size distribution of the lake sediment profile and rainfall erosivities calculated from Longxi catchment metrological records...
January 12, 2017: Chemosphere
Mohammed Danish, Waheed Ahmad Khanday, Rokiah Hashim, Nurul Syuhada Binti Sulaiman, Mohammad Nishat Akhtar, Maniruddin Nizami
Box-Behnken model of response surface methodology was used to study the effect of adsorption process parameters for Rhodamine B (RhB) removal from aqueous solution through optimized large surface area date stone activated carbon. The set experiments with three input parameters such as time (10-600min), adsorbent dosage (0.5-10g/L) and temperature (25-50°C) were considered for statistical significance. The adequate relation was found between the input variables and response (removal percentage of RhB) and Fisher values (F- values) along with P-values suggesting the significance of various term coefficients...
February 3, 2017: Ecotoxicology and Environmental Safety
Elisabeth Edvardsen, Aina Akerø, Ole Henning Skjønsberg, Bjørn Skrede
BACKGROUND: Air travel may imply a health hazard for patients with cystic fibrosis (CF) due to hypobaric environment in the aircraft cabin. The objective was to identify pre-flight variables, which might predict severe hypoxaemia in adult CF patients during air travel. METHODS: Thirty adult CF-patients underwent pre-flight evaluation with spirometry, arterial oxygen tension (PaO2), pulse oximetry (SpO2) and cardiopulmonary exercise testing (CPET) at sea level (SL)...
February 6, 2017: BMC Research Notes
Andrew W Wilson, Kentaro Hosaka, Gregory M Mueller
A systematic and evolutionary ecology study of the model ectomycorrhizal (ECM) genus Laccaria was performed using herbarium material and field collections from over 30 countries covering its known geographic range. A four-gene (nrITS, 28S, RPB2, EF1α) nucleotide sequence dataset consisting of 232 Laccaria specimens was analyzed phylogenetically. The resulting Global Laccaria dataset was used for molecular dating and estimating diversification rates in the genus. Stable isotope analysis of carbon and nitrogen was used to evaluate the origin of Laccaria's ECM ecology...
March 2017: New Phytologist
Ryo Kuriki, Kazuhiko Maeda
Photocatalytic CO2 reduction with visible light has long been studied as a potential means to address the problems of global warming and the depletion of fossil fuels. Hybrid systems that consist of a metal complex and a particulate semiconductor are expected to be promising because of the excellent electrochemical (and/or photocatalytic) ability of metal complexes for CO2 reduction and the high efficiency of semiconductors for water oxidation. However, a satisfactory system has not been developed to date. Our group has been developing such hybrid materials for visible-light-driven CO2 reduction...
February 6, 2017: Physical Chemistry Chemical Physics: PCCP
Stefania Pinto, Fabio Gatti, Luis G García-Montero, Cristina Menta
There are numerous aspects related to Tuber species, which have not been explored to date. Tuber aestivum Vitt. is an ectomycorrhizal fungus, that produces an area (called brûlé) around the host plant trunk, where the germination of other plants is inhibited. What happens inside this particular environment is still not sufficiently understood, especially in terms of soil fauna. A previous work showed that there were higher microarthropod abundances outside during the period of maximum activity of the mycelium...
February 1, 2017: Science of the Total Environment
Khurram Shehzad, Yang Xu, Chao Gao, Hanying Li, Zhimin Dang, Tawfique Hasan, Jack Jikui Luo, Xiangfeng Duan
Polymer dielectrics offer key advantages over their ceramic counterparts such as flexibility, scalability, low-cost, and high-breakdown voltages. However, a major drawback that limits more widespread application of polymer dielectrics is their temperature-dependent dielectric properties. To achieve dielectric constants with low/zero temperature coefficient (L/0TC) over a broad temperature range is essential for applications in diverse technologies. Here, we report a hybrid filler strategy to produce polymer composites with an ultra-wide L/0TC window of dielectric constant, as well as significantly enhanced dielectric value, maximum energy storage density, thermal conductivity and stability...
February 3, 2017: ACS Applied Materials & Interfaces
Zhi-Guo Wu, Fang Wang, Li-Qun Ning, Robert D Stedtfeld, Zong-Zheng Yang, Jing-Guo Cao, Hong-Jie Sheng, Xin Jiang
Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloronitrobenzene, was able to co-metabolize 5-chloro-2-picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp...
February 2, 2017: Biodegradation
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