Read by QxMD icon Read

CO2 removal

Yuansheng Hu, Xiaodi Hao, Mark van Loosdrecht, Huiqin Chen
Microalgae cultivation is a promising technology for integrated effluent polishing and biofuel production, but poor separability of microalgal cells hinders its industrial application. This study intended to selectively enrich settleable microalgal consortia in mixed culture by applying "wash-out" pressure, which was realized by controlling settling time (ST) and volume exchange ratio (VER) in photo-SBRs. The results demonstrated that highly settleable microalgal consortia (settling efficiency>97%; SVI = 17-50 mL/g) could be enriched from indigenous algal cultures developed in WWTP's effluent...
August 15, 2017: Water Research
Michael Köhl, Prem R Neupane, Neda Lotfiomran
The world's forests play a pivotal role in the mitigation of global climate change. By photosynthesis they remove CO2 from the atmosphere and store carbon in their biomass. While old trees are generally acknowledged for a long carbon residence time, there is no consensus on their contribution to carbon accumulation due to a lack of long-term individual tree data. Tree ring analyses, which use anatomical differences in the annual formation of wood for dating growth zones, are a retrospective approach that provides growth patterns of individual trees over their entire lifetime...
2017: PloS One
Michael Fischer
Zeolites and structurally related materials (zeotypes) have received considerable attention as potential adsorbents for selective carbon dioxide adsorption. Within this group, zeotypes with aluminophosphate composition (AlPOs) could be an interesting alternative to the more frequently studied aluminosilicate zeolites. So far, however, only a few AlPOs have been characterised experimentally in terms of their CO2 adsorption properties. In this study, force-field based grand-canonical Monte Carlo (GCMC) simulations were used to evaluate the potential of AlPOs for CO2/N2 separation, a binary mixture that constitutes a suitable model system for the removal of carbon dioxide from flue gases...
August 16, 2017: Physical Chemistry Chemical Physics: PCCP
Marcel Schulte, Maik A Jochmann, Tobias Gehrke, Andrea Thom, Tim Ricken, Martin Denecke, Torsten C Schmidt
Biological methane oxidation may be regarded as a method of aftercare treatment for landfills to reduce climate relevant methane emissions. It is of social and economic interest to estimate the behavior of bacterial methane oxidation in aged landfill covers due to an adequate long-term treatment of the gas emissions. Different approaches assessing methane oxidation in laboratory column studies have been investigated by other authors recently. However, this work represents the first study in which three independent approaches, ((i) mass balance, (ii) stable isotope analysis, and (iii) stoichiometric balance of product (CO2) and reactant (CH4) by CO2/CH4-ratio) have been compared for the estimation of the biodegradation by a robust statistical validation on a rectangular, wide soil column...
August 12, 2017: Waste Management
L Monteiro, C Barbieri, S Warnakulasuriya, M Martins, F Salazar, J-J Pacheco, P Vescovi, M Meleti
BACKGROUND: Oral leukoplakia (OL) is the most typical potentially malignant disorder of the oral mucosa. We aimed to evaluate the clinical outcome of oral leukoplakia treated with several types of lasers and with the use of quantic molecular resonance (QMR) lancet, in terms of recurrence rate. MATERIAL AND METHODS: Eighty-seven previously untreated OL (52 occurring in females and 35 in males, mean age of 59.4 ± 13.9 years) were consecutively submitted to surgical treatment at University Hospital of Parma, Italy, and Hospital de Valongo, Portugal, (1999 to 2012)...
August 15, 2017: Medicina Oral, Patología Oral y Cirugía Bucal
Trisha L Dupnock, Marc A Deshusses
This research reports the development of a biotrickling filter (BTF) to upgrade biogas, which is achieved by adding H2 to reduce CO2. H2 and CO2 (80:20% vol.) were fed to a bench-scale BTF packed with polyurethane foam (PUF) and inoculated with hydrogenotrophic methanogens. Maximum CH4 production rates recorded were as high as 38 m(3)CH4 m(-3)reactor day(-1), which is 5-30 times faster than earlier reports with other kinds of bioreactors. The high rates were attributed to the efficient mass transfer and high density of methanogens in the BTF...
August 14, 2017: Applied Biochemistry and Biotechnology
Chunhao Zhai, Sadhan C Jana
The suitability of monolithic polyimide aerogels as filter media for removal of airborne nanoparticles was investigated in this work by considering two solvents, N-methyl pyrrolidone (NMP) and dimethylformamide (DMF) for tuning of meso- and macropore content. Polyimide gels were synthesized from the chemical reactions between solutions of pyromellitic dianhydride, 2,2'-dimethylbenzidine, and 1, 3, 5-triaminophenoxylbenzene. The gels were dried via supercritical drying in CO2 to obtain the aerogels. The porosity of polyimide aerogels was varied by changing the initial concentration of the solids in the solutions in the range of 2...
August 14, 2017: ACS Applied Materials & Interfaces
Manuel S Godoy, Beatrice Mongili, Debora Fino, M Auxiliadora Prieto
Human activity has been altering many ecological cycles for decades, disturbing the natural mechanisms which are responsible for re-establishing the normal environmental balances. Probably, the most disrupted of these cycles is the cycle of carbon. In this context, many technologies have been developed for an efficient CO2 removal from the atmosphere. Once captured, it could be stored in large geological formations and other reservoirs like oceans. This strategy could present some environmental and economic problems...
August 14, 2017: Microbial Biotechnology
Yuan Zhuang, Fei Yu, Jie Ma, Junhong Chen
Alginate/graphene double network hydrogel has recently been demonstrated as a promising adsorbent for water pollutants. To improve the adsorption capacity of the double network hydrogel, physical and chemical modifications are made to obtain an excellent porous structure and more functional groups. As-modified alginate/graphene double network hydrogel has a higher hydroxyl group content under a higher polyvinyl alcohol content and a higher carboxyl group content with a higher oxidation degree. Moreover, the CO2 produced by CaCO3 is used as pore formation agent avoiding the use of toxic organic matters...
July 11, 2017: Journal of Colloid and Interface Science
A J Thompson, L H Marks, M J Goudie, A Rojas-Pena, H Handa, J A Potkay
Artificial lungs have been used in the clinic for multiple decades to supplement patient pulmonary function. Recently, small-scale microfluidic artificial lungs (μAL) have been demonstrated with large surface area to blood volume ratios, biomimetic blood flow paths, and pressure drops compatible with pumpless operation. Initial small-scale microfluidic devices with blood flow rates in the μl/min to ml/min range have exhibited excellent gas transfer efficiencies; however, current manufacturing techniques may not be suitable for scaling up to human applications...
March 2017: Biomicrofluidics
Yu Katayama, Kosuke Yamauchi, Kohei Hayashi, Takeou Okanishi, Hiroki Muroyama, Toshiaki Matsui, Yuuki Kikkawa, Takayuki Negishi, Shin Watanabe, Takenori Isomura, Koichi Eguchi
Over the last few decades, because of the significant development of anion exchange membranes, increasing efforts have been devoted the realization of anion exchange membrane fuel cells (AEMFCs) that operate with the supply of hydrogen generated on-site. In this paper, ammonia was selected as a hydrogen source, following which the effect of conceivable impurities, unreacted NH3 and atmospheric CO2, on the performance of AEMFCs was established. As expected, we show that these impurities worsen the performance of AEMFCs significantly...
August 21, 2017: ACS Applied Materials & Interfaces
Simon Habran, Thomas Desaive, Philippe Morimont, Bernard Lambermont, Pierre Dauby
The extracorporeal CO2 removal device (ECCO2RD) is used in clinics to treat patients suffering from respiratory failures like acute respiratory distress syndrome (ARDS) or chronic obstructive pulmonary disease (COPD). The aim of this device is to decarboxylate blood externally with low blood flow. A mathematical model is proposed to describe protective ventilation, ARDS, and an extracorporeal CO2 removal therapy (ECCO2RT). The simulations are compared with experimental data carried out on ten pigs. The results show a good agreement between the mathematical simulations and the experimental data, which provides a nice validation of the model...
August 9, 2017: Medical & Biological Engineering & Computing
Changchang Zou, Qianqian Li, Yinying Hua, Bihang Zhou, Jingui Duan, Wanqin Jin
Covalent organic framework (COF) membranes used for selective removal of CO2 were believed as an efficient and low-cost solution to energy and environmental sustainability. In this study, the amide modified COF nanosheet cluster with a 2D structure was facilely prepared through solid reaction, exhibiting good adsorption-based CO2 selectivity (223 at 273 K and 90 at 298 K) toward N2. Remarkably, the mixed matrix membrane (MMM) that consists of a lesser amount of COF filler (1 wt %) shows promising CO2/N2 gas selectivity (∼64)...
August 21, 2017: ACS Applied Materials & Interfaces
Yuanfei Li, Wei Jin, Chunlong Mu, Yanfen Cheng, Weiyun Zhu
Anaerobic fungi are potent lignocellulose degraders, but have not yet been exploited in this capacity, largely owing to their poor metabolic characterization. In the current study, a time course of fermentation was conducted to study the effect of the co-cultured methanogens on xylose metabolism by anaerobic fungi. The fermentation end-products from anaerobic fungal monoculture were H2 (6.7 ml), CO2 (65.7 ml), formate (17.90 mM), acetate (9.00 mM), lactate (11.89 mM), ethanol, and malate after 96 h fermentation...
August 9, 2017: Journal of Basic Microbiology
Heejung S Jung, Michael L Grady, Tristan Victoroff, Arthur L Miller
Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle...
July 2017: Atmospheric Environment
Claudia Isela Granada-Moreno, Arturo Aburto-Medina, Daniel de Los Cobos Vasconcelos, Armando González-Sánchez
AIMS: To achieve the functional specialization of a microalgae community through operational tuning of an open-photobioreactor used for biogas upgrading under alkaline conditions. METHODS AND RESULTS: An open-photobioreactor was inoculated with an indigenous microalgae sample from the Texcoco Soda-Lake. A microalgae community was adapted to fix CO2 from synthetic biogas through different culture conditions reaching a maximum of 220 mg CO2 L(-1) d(-1) . Picochlorum sp...
August 3, 2017: Journal of Applied Microbiology
Ashish Verma, Dinesh De, Kapil Tomar, Parimal K Bharadwaj
A highly porous and thermally stable anionic Zn(II)-framework, {[(CH3)2NH2(+)]2[Zn3((μ3-O))(L)2(H2O)]·4DMF·2H2O}n (1), having exposed metal sites and pendant amine groups has been synthesized adopting the solvothermal technique. This anionic 3D framework showed two-fold interpenetration with 45.1% void volume. It has a 3,6-c binodal net with rare sit 3,6-conn topology. The metal bound aqua ligand could be easily removed along with the guest molecules in the lattice upon activation to afford the desolvated framework 1'...
August 3, 2017: Inorganic Chemistry
Christian Karagiannidis, Stephan Strassmann, Daniel Brodie, Philine Ritter, Anders Larsson, Ralf Borchardt, Wolfram Windisch
BACKGROUND: Veno-venous extracorporeal CO2 removal (vv-ECCO2R) is increasingly being used in the setting of acute respiratory failure. Blood flow rates through the device range from 200 ml/min to more than 1500 ml/min, and the membrane surface areas range from 0.35 to 1.3 m(2). The present study in an animal model with similar CO2 production as an adult patient was aimed at determining the optimal membrane lung surface area and technical requirements for successful vv-ECCO2R. METHODS: Four different membrane lungs, with varying lung surface areas of 0...
December 2017: Intensive Care Medicine Experimental
Yu Bai, Yen Nan Liang, Xiao Hu
Perennial problems of adsorption in wastewater treatment include adsorbent recycling, generation of waste sludge and secondary pollution because harmful concentrated acids, bases or strong chelators are often used for adsorbent regeneration and adsorbate recovery. We report, for the first time, an eco-friendly regeneration concept demonstrated with a CO2-responsive octopus-like polymeric adsorbent. Various heavy metals can be scavenged at very high Qe by such adsorbent through coordination. Most importantly, the rapid and complete regeneration of the adsorbent and recovery of the heavy metal ions can be readily achieved by CO2 bubbling within a few minutes under mild conditions, i...
October 2017: Chemosphere
Xiaoguo Wang, Minghua Zhou, Tao Li, Yun Ke, Bo Zhu
In the humid subtropics, conversion of cropland to forest has been recognized to influence carbon cycling (e.g., soil CO2 emissions) and the associated ecosystem carbon balance. A three-year field study was conducted in situ to quantitatively evaluate effects of land use change on carbon budget in a cropland (under winter wheat-summer maize rotation) comparison with the adjacent forest ecosystem. During the three-year experimental period, on average, soil heterotrophic respirations were 35.19mgC·m(-2)·h(-1) for the cropland and 40...
July 27, 2017: Science of the Total Environment
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"