182 research outputs found
Caffeine-derived noble carbons as ball milling-resistant cathode materials for lithium-ion capacitors
Energy consumption is a growing phenomenon in our society causing many negative effects such as global warming. There is a need for the development of new sustainable materials for energy storage. Carbons are materials derivable from biowaste that can rather easily store energy due to their high conductivity and surface area. However, their large-scale processing is challenging as derived materials can be rather heterogeneous and homogenization requires ball milling, a process that can damage carbons in the process of oxidation. Herein, we have prepared caffeine-derived noble nitrogen-doped carbon that withstands the ball milling process without significant oxidation. Additionally, it performs extraordinarily as a cathode material for lithium-ion capacitors, making it an attractive biowaste-derived alternative to commercial heavy metal cathodes
PtRu nanoparticles supported on noble carbons for ethanol electrooxidation
In this work, three cytosine derived nitrogen doped carbonaceous materials (noble carbons, NCs) with different atomic C/N ratios and porous networks have been synthesized and used as supports for PtRu electrocatalysts in the ethanol oxidation reaction (EOR) for clean hydrogen production. Both, the metal phase and the carbon support play critical roles in the electrocatalysts final performance. Lower NPs size distribution was obtained over supports with low atomic C/N ratios (i.e., 4 and 6) and defined porosity (i.e., 1701Â m2 gâ1 for PtRu/CNZ and 1834Â m2 gâ1 for PtRu/CLZ, respectively). In contrast, a lower C/N ratio and poor porous network (i.e., 65Â m2 gâ1, PtRu/CLK) led to the largest particle size and fostered an increase of the alloying degree between Pt and Ru NPs (i.e., 3 for C/NÂ ~Â 6 and 28 for C/NÂ ~Â 3). Electrochemical active surface area was found to increase with decreasing NPs size and the alloy extent, due to a higher availability of Pt active sites. Accelerated degradation tests showed that PtRu/NCs outperform similar to PtRu NPs on commercial carbon pointing at the stabilizing effect of NCs. PtRu/CNZ exhibited the best electrochemical performance (i.e., 69.1Â mA mgPtâ1), outperforming PtRu/CLZ and PtRu/CLK by 3- and 9-fold, respectively, due to a suitable compromise between particle sizes, degree of alloy, textural properties and elemental composition. Best anodes were scaled-up to a proton exchange membrane cell and PtRu/CNZ was proved to provide the best electrocatalytic activity (262Â mAÂ cmâ2 and low energy requirements), matching the values obtained by the state of the art of EOR electrocatalysts
COSMO-RS Selection and Solubility Experiments
Funding Information: This work was also supported by Associate Laboratory for Green ChemistryâLAQV, financed by national funds from FCT/MCTES (UID/QUI/50006/2020), the contracts of Individual Call to Scientific Employment Stimulus 2020.00835.CEECIND (J.M.M.A.)/2021.01432.CEECIND (A.B.P.) and by FCT/MCTES (Portugal) through the project PTDC/EQU-EQU/29737/2017. The authors thank Solvay for providing the ionic liquid tri(butyl) ethylphosphonium diethylphosphate. M.C.G. and J.A. thank IDEX-LYON for financial support (Programme Investissement dâAvenir ANR-16-IDEX-0005). Publisher Copyright: © 2022 American Chemical Society. All rights reserved.In recent years, the fight against climate change and the mitigation of the impact of fluorinated gases (F-gases) on the atmosphere is a global concern. Development of technologies that help to efficiently separate and recycle hydrofluorocarbons (HFCs) at the end of the refrigeration and air conditioning equipment life is a priority. The technological development is important to stimulate the F-gas capture, specifically difluoromethane (R-32) and 1,1,1,2-tetrafluoroethane (R-134a), due to their high global warming potential. In this work, the COSMO-RS method is used to analyze the solute-solvent interactions and to determine Henry's constants of R-32 and R-134a in more than 600 ionic liquids. The three most performant ionic liquids were selected on the basis of COSMO-RS calculations, and F-gas absorption equilibrium isotherms were measured using gravimetric and volumetric methods. Experimental results are in good agreement with COSMO-RS predictions, with the ionic liquid tributyl(ethyl)phosphonium diethyl phosphate, [P2444][C2C2PO4], being the salt presenting the highest absorption capacities in molar and mass units compared to salts previously tested. The other two ionic liquids selected, trihexyltetradecylphosphonium glycinate, [P66614][C2NO2], and trihexyl(tetradecyl)phosphonium 2-cyano-pyrrole, [P66614][CNPyr], may be competitive as far as their absorption capacities are concerned. Future works will be guided on evaluating the performance of these ionic liquids at an industrial scale by means of process simulations, in order to elucidate the role in process efficiency of other relevant absorbent properties such as viscosity, molar weight, or specific heat.publishersversionpublishe
Magnetochronology of the Entire Chinle Formation (Norian Age) in a Scientific Drill Core From Petrified Forest National Park (Arizona, USA) and Implications for Regional and Global Correlations in the Late Triassic
Building on an earlier study that confirmed the stability of the 405âkyr eccentricity climate cycle and the timing of the NewarkâHartford astrochronostratigraphic polarity time scale back to 215 Ma, we extend the magnetochronology of the Late Triassic Chinle Formation to its basal unconformity in scientific drill core PFNPâ1A from Petrified Forest National Park (Arizona, USA). The 335âmâthick Chinle section is imprinted with paleomagnetic polarity zones PF1r to PF10n, which we correlate to chrons E17r to E9n (~209 to 224 Ma) of the NewarkâHartford astrochronostratigraphic polarity time scale. A sediment accumulation rate of ~34 m/Myr can be extended down to ~270 m, close to the base of the Sonsela Member and the base of magnetozone PF5n, which we correlate to chron E14n that onsets at 216.16 Ma. Magnetozones PF5r to PF10n in the underlying 65âmâthick section of the mudstoneâdominated Blue Mesa and Mesa Redondo members plausibly correlate to chrons E13r to E9n, indicating a sediment accumulation rate of only ~10 m/Myr. Published highâprecision UâPb detrital zircon dates from the lower Chinle tend to be several million years older than the magnetochronological age model. The source of this discrepancy is unclear but may be due to sporadic introduction of juvenile zircons that get recycled. The new magnetochronological constraint on the base of the Sonsela Member brings the apparent timing of the included Adamanianâ Revueltian land vertebrate faunal zone boundary and the Zone II to Zone III palynofloral transition closer to the temporal range of the ~215 Ma Manicouagan impact structure in Canada
TRAF3IP2 gene is associated with cutaneous extraintestinal manifestations in Inflammatory bowel disease
Background and aims: Genome-wide association (GWA) studies recently identified a novel gene, TRAF3IP2, involved in the susceptibility to psoriasis. Common immune-mediated mechanisms involving the skin or the gut have been suggested. We therefore aimed to assess the role of TRAF3IP2 gene in IBD, with particular regard to the development of cutaneous extraintestinal manifestations (pyoderma gangrenosum, erythema nodosum). The association with psoriasis was also assessed in a secondary analysis. Methods: The analysis included 267 Crohn's disease (CD), 200 ulcerative colitis (UC) patients and 278 healthy controls. Three TRAF3IP2 SNPs were genotyped by allelic discrimination assays. A case/control association study and a genotype/phenotype correlation analysis have been performed. Results: All three SNPs conferred a high risk to develop cutaneous manifestations in IBD. A higher risk of pyoderma gangrenosum and erythema nodosum was observed in CD patients carrying the Rs33980500 variant (OR 3.03; P=0.026)In UC, a significantly increased risk was observed for both the Rs13190932 and the Rs13196377 SNPs (OR 5.05; P=0.02 and OR 4.1; P=0.049). Moreover, association of TRAF3IP2 variants with ileal (OR = 1.92), fibrostricturing (OR = 1.91) and perianal CD (OR = 2.03) was observed. Conclusions: This is the first preliminary report indicating that TRAF3IP2 variants increase the risk of cutaneous extraintestinal manifestations in IBD suggesting that the analysis of the TRAF3IP2 variants may be useful for identifying IBD patients at risk to develop these manifestations. © 2012 European Crohn's and Colitis Organisation
Empirical evidence for stability of the 405-kiloyear Jupiter-Venus eccentricity cycle over hundreds of millions of years
The NewarkâHartford astrochronostratigraphic polarity timescale (APTS) was developed using a theoretically constant 405-kiloyear eccentricity cycle linked to gravitational interactions with JupiterâVenus as a tuning target and provides a major timing calibration for about 30 million years of Late Triassic and earliest Jurassic time. While the 405-ky cycle is both unimodal and the most metronomic of the major orbital cycles thought to pace Earthâs climate in numerical solutions, there has been little empirical confirmation of that behavior, especially back before the limits of orbital solutions at about 50 million years before present. Moreover, the APTS is anchored only at its younger end by UâPb zircon dates at 201.6 million years before present and could even be missing a number of 405-ky cycles. To test the validity of the dangling APTS and orbital periodicities, we recovered a diagnostic magnetic polarity sequence in the volcaniclastic-bearing Chinle Formation in a scientific drill core from Petrified Forest National Park (Arizona) that provides an unambiguous correlation to the APTS. New high precision UâPb detrital zircon dates from the core are indistinguishable from ages predicted by the APTS back to 215 million years before present. The agreement shows that the APTS is continuous and supports a stable 405-kiloyear cycle well beyond theoretical solutions. The validated NewarkâHartford APTS can be used as a robust framework to help differentiate provinciality from global temporal patterns in the ecological rise of early dinosaurs in the Late Triassic, amongst other problems
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U-Pb zircon geochronology and depositional age models for the Upper Triassic Chinle Formation (Petrified Forest National Park, Arizona, USA): implications for Late Triassic paleoecological and paleoenvironmental change
The Upper Triassic Chinle Formation is a critical non-marine archive of low-paleolatitude biotic and environmental change in southwestern North America. The well-studied and highly fossiliferous Chinle strata at Petrified Forest National Park (PFNP), Arizona, preserve a biotic turnover event recorded by vertebrate and palynomorph fossils, which has been alternatively hypothesized to coincide with tectonically driven climate change or with the Manicouagan impact event at ca. 215.5 Ma. Previous outcrop-based geochronologic age constraints are difficult to put in an accurate stratigraphic framework because lateral facies changes and discontinuous outcrops allow for multiple interpretations. A major goal of the Colorado Plateau Coring Project (CPCP) was to retrieve a continuous record in unambiguous superposition designed to remedy this situation. We sampled the 520-m-long core 1A of the CPCP to develop an accurate age model in unquestionable superposition by combining U-Pb zircon ages and magnetostratigraphy. From 13 horizons of volcanic detritus-rich siltstone and sandstone, we screened up to âŒ300 zircon crystals per sample using laser ablationâinductively coupled plasmaâmass spectrometry and subsequently analyzed up to 19 crystals of the youngest age population using the chemical abrasionâisotope dilutionâthermal ionization mass (CA-ID-TIMS) spectrometry method. These data provide new maximum depositional ages for the top of the Moenkopi Formation (ca. 241 Ma), the lower Blue Mesa Member (ca. 222 Ma), and the lower (ca. 218 to 217 Ma) and upper (ca. 213.5 Ma) Sonsela Member. The maximum depositional ages obtained for the upper Chinle Formation fall well within previously proposed age constraints, whereas the maximum depositional ages for the lower Chinle Formation are relatively younger than previously proposed ages from outcrop; however, core to outcrop stratigraphic correlations remain uncertain. By correlating our new ages with the magnetostratigraphy of the core, two feasible age model solutions can be proposed. Model 1 assumes that the youngest, coherent U-Pb age clusters of each sample are representative of the maximum depositional ages and are close to (227 Ma) in age, and hence the biotic turnover event cannot be correlated to the CarnianâNorian boundary but is rather a mid-Norian event. Our age models demonstrate the powers, but also the challenges, of integrating detrital CA-ID-TIMS ages with magnetostratigraphic data to properly interpret complex sedimentary sequences
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LA-ICPMS U-Pb geochronology of detrital zircon grains from the Coconino, Moenkopi, and Chinle Formations in the Petrified Forest National Park (Arizona)
Uraniumâlead (UâPb) geochronology was conducted by laser ablation â inductively coupled plasma mass spectrometry (LA-ICPMS) on 7175 detrital zircon grains from 29 samples from the Coconino Sandstone, Moenkopi Formation, and Chinle Formation. These samples were recovered from âŒâ520âm of drill core that was acquired during the Colorado Plateau Coring Project (CPCP), located in Petrified Forest National Park (Arizona).
A sample from the lower Permian Coconino Sandstone yields a broad distribution of Proterozoic and Paleozoic ages that are consistent with derivation from the Appalachian and Ouachita orogens, with little input from local basement or Ancestral Rocky Mountain sources. Four samples from the Holbrook Member of the Moenkopi Formation yield a different set of Precambrian and Paleozoic age groups, indicating derivation from the Ouachita orogen, the East Mexico arc, and the Permo-Triassic arc built along the Cordilleran margin.
A total of 23 samples from the Chinle Formation contain variable proportions of Proterozoic and Paleozoic zircon grains but are dominated by Late Triassic grains. LA-ICPMS ages of these grains belong to five main groups that correspond to the Mesa Redondo Member, Blue Mesa Member and lower part of the Sonsela Member, upper part of the Sonsela Member, middle part of the Petrified Forest Member, and upper part of the Petrified Forest Member. The ages of pre-Triassic grains also correspond to these chronostratigraphic units and are interpreted to reflect varying contributions from the Appalachian orogen to the east, Ouachita orogen to the southeast, Precambrian basement exposed in the ancestral Mogollon Highlands to the south, East Mexico arc, and PermianâTriassic arc built along the southern Cordilleran margin. Triassic grains in each chronostratigraphic unit also have distinct U and thorium (Th) concentrations, which are interpreted to reflect temporal changes in the chemistry of arc magmatism.
Comparison of our LA-ICPMS ages with available chemical abrasion thermal ionization mass spectrometry (CA-TIMS) ages and new magnetostratigraphic data provides new insights into the depositional history of the Chinle Formation, as well as methods utilized to determine depositional ages of fluvial strata. For parts of the Chinle Formation that are dominated by fine-grained clastic strata (e.g., mudstone and siltstone), such as the Blue Mesa Member and Petrified Forest Member, all three chronometers agree (to within âŒâ1âMyr), and robust depositional chronologies have been determined. In contrast, for stratigraphic intervals dominated by coarse-grained clastic strata (e.g., sandstone), such as most of the Sonsela Member, the three chronologic records disagree due to recycling of older zircon grains and variable dilution of syn-depositional-age grains. This results in LA-ICPMS ages that significantly predate deposition and CA-TIMS ages that range between the other two chronometers. These complications challenge attempts to establish a well-defined chronostratigraphic age model for the Chinle Formation
Colorado Plateau Coring Project, Phase I (CPCP-I): a continuously cored, globally exportable chronology of Triassic continental environmental change from western North America
Phase 1 of the Colorado Plateau Coring
Project (CPCP-I) recovered a total of over 850 m of stratigraphically
overlapping core from three coreholes at two sites in the Early to Middle
and Late Triassic age largely fluvial Moenkopi and Chinle formations in
Petrified Forest National Park (PFNP), northeastern Arizona, USA. Coring took
place during November and December of 2013 and the project is now in its
post-drilling science phase. The CPCP cores have abundant detrital
zircon-producing layers (with survey LA-ICP-MS dates selectively resampled
for CA-ID-TIMS U-Pb ages ranging in age from at least 210 to 241 Ma), which
together with their magnetic polarity stratigraphy demonstrate that a
globally exportable timescale can be produced from these continental
sequences and in the process show that a prominent gap in the calibrated
Phanerozoic record can be filled. The portion of core CPCP-PFNP13-1A for
which the polarity stratigraphy has been completed thus far spans ââŒâ215
to 209 Ma of the Late Triassic age, and strongly validates the longer
Newark-Hartford Astrochronostratigraphic-calibrated magnetic Polarity
Time-Scale (APTS) based on cores recovered in the 1990s during the Newark
Basin Coring Project (NBCP).Core recovery was ââŒâ100 % in all holes (Table 1). The coreholes were
inclined ââŒâ60â75° approximately to the south to ensure azimuthal
orientation in the nearly flat-lying bedding, critical to the interpretation
of paleomagentic polarity stratigraphy. The two longest of the cores
(CPCP-PFNP13-1A and 2B) were CT-scanned in their entirety at the University
of Texas High Resolution X-ray CT Facility in Austin, TX, and subsequently
along with 2A, all cores were split and processed at the CSDCO/LacCore
Facility, in Minneapolis, MN, where they were scanned for physical property
logs and imaging. While remaining the property of the Federal Government, the
archive half of each core is curated at the NSF-sponsored LacCore Core
Repository and the working half is stored at the Rutgers University Core
Repository in Piscataway, NJ, where the initial sampling party was held in
2015 with several additional sampling events following. Additional planned
study will recover the rest of the polarity stratigraphy of the cores as
additional zircon ages, sedimentary structure and paleosol facies analysis,
stable isotope geochemistry, and calibrated XRF core scanning are
accomplished. Together with strategic outcrop studies in Petrified Forest
National Park and environs, these cores will allow the vast amount of surface
paleontological and paleoenvironmental information recorded in the
continental Triassic of western North America to be confidently placed in a
secure context along with important events such as the giant Manicouagan
impact at ââŒâ215.5 Ma (Ramezani et al., 2005) and long wavelength
astronomical cycles pacing global environmental change and trends in
atmospheric gas composition during the dawn of the dinosaurs.</p
Metabolic Syndrome (MetS), Systemic Inflammatory Response Syndrome (SIRS), and Frailty: Is There any Room for Good Outcome in the Elderly Undergoing Emergency Surgery?
Background: Patients with MetS or SIRS experience higher rates of mortality and morbidity, across both cardiac and noncardiac surgery. Frailty assessment has acquired increasing importance in recent years as it predisposes elderly patients to a worse outcome. The aim of our study was to investigate the influence of MetS, SIRS, and with or without frailty on elderly patients undergoing emergency surgical procedures. Methods: We analyzed data of all patients with nonmalignant diseases requiring an emergency surgical procedure from January 2017 to December 2020. The occurrence of MetS was identified using modified definition criteria used by the NCEP-ATP III Expert Panel: obesity, hypertension, diabetes, or if medication for high triglycerides or for low HDL cholesterol was taken. Systemic inflammatory response syndrome (SIRS) was evaluated according to the original consensus study (Sepsis-1). The frailty profile was investigated by the 5-modified Frailty Index (5-mFI) and the Emergency Surgery Frailty Index (EmSFI). Postoperative complications have been reported and categorized according to the ClavienâDindo (CâD) classification system. Morbidity and mortality have been mainly considered as the 30-day standard period definition. Results: Of the 2,318 patients included in this study, 1,010 (43.6%) fulfilled the criteria for MetS (MetsG group). Both 5-Items score and EmsFI showed greater fragility in patients with MetS. All patients with MetS showed more frequently a CACI index greater than 6. The occurrence of SIRS was higher in MetSG. LOS was longer in patients with MetS (MetSG 11.4 ± 12 days vs. n-MetSG 10.5 ± 10.2 days, p = 0.046). MetSG has a significantly higher rate of morbidity (353 (35.%) vs. 385 (29.4%), p = 0.005). The mortality rate in patients with MetS (98/1010, 10%) was similar to that in patients without it (129/1308, 10%). Considering patients with MetS who developed SIRS and those who had frailty or both, the occurrence of these conditions was associated with a higher rate of morbidity and mortality. Conclusion: Impact of MetS and SIRS on elderly surgical patient outcomes has yet to be fully elucidated. The present study showed a 43.6% incidence of MetS in the elderly population. In conclusion, age per se should be not considered anymore as the main variable to estimate patient outcomes, while MetS and Frailty should have always a pivotal role
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