Chemically functionalized carbon nanotubes with pyridine groups as easily tunable N-decorated nanomaterials for the oxygen reduction reaction in alkaline medium

We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism. © 2014 American Chemical Society

Chemically functionalized carbon nanotubes with pyridine groups as easily tunable N-decorated nanomaterials for the oxygen reduction reaction in alkaline medium

We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism. © 2014 American Chemical Society

The phylodynamics of SARS-CoV-2 during 2020 in Finland

Finland has had a low incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infections as compared to most European countries. Here we report the origins and turnover of SARS-CoV-2 lineages circulating in Finland in 2020. SARS-CoV-2 introduced to Finland in January 2020 and spread rapidly across southern Finland during spring. We observed rapid turnover among Finnish lineages during this period. Clade 20C became the most prevalent among sequenced cases and was replaced by other strains in fall 2020. Bayesian phylogeographic reconstructions suggested 42 independent introductions into Finland during spring 2020, mainly from Italy, Austria, and Spain, which might have been the source for a third of cases. The investigations of the original introductions of SARS-CoV-2 to Finland during the early stages of the pandemic and of the subsequent lineage dynamics could be utilized to assess the role of transboundary movements and effects of early intervention and public health measures.Peer reviewe

A highly N-doped carbon phase "dressing" of macroscopic supports for catalytic applications

© The Royal Society of Chemistry 2015. The straightforward "dressing" of macroscopically shaped supports (i.e. β-SiC and α-Al2O3) with a mesoporous and highly nitrogen-doped carbon-phase starting from food-processing raw materials is described. The as-prepared composites serve as highly efficient and selective metal-free catalysts for promoting industrial key-processes at the heart of renewable energy technology and environmental protection

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Nitrogen-doped carbon nanotubes decorated silicon carbide as a metal-free catalyst for partial oxidation of H(2)S

Abstract not availableCuong Duong-Viet, Lai Truong-Phuoc, Tung Tran-Thanh, Jean-Mario Nhut, Lam Nguyen-Dinh, Izabela Janowska, Dominique Begin, Cuong Pham-Hu

Chemically functionalized carbon nanotubes with pyridine groups as easily tunable N-decorated nanomaterials for the oxygen reduction reaction in alkaline medium

We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism. © 2014 American Chemical Society

Chemically functionalized carbon nanotubes with pyridine groups as easily tunable N-decorated nanomaterials for the oxygen reduction reaction in alkaline medium

We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism. © 2014 American Chemical Society

Cotton fabrics coated with few-layer graphene as highly responsive surface heaters and integrated lightweight electronic-textile circuits

© 2020 American Chemical Society In this work, we describe an eco-friendly and cost-efficient method for the production of highly dispersed few-layer graphene solutions using karaya gum as a bioinspired exfoliating agent. The as-synthesized graphene aqueous solutions can be easily applied on a cotton cloth through dip- or brush-coating, thanks to the interaction between the graphene sheets decorated with the gum and the functional groups on the cotton cloth host substrate surface. The as-prepared fabric composites display high mechanical stability, anchorage, and high electrical conductivity that make them excellent candidates within a relatively high number of technological applications. The study mainly focuses on the potentialities of cotton fabric composites as planar heating devices or electronic-textile (e-textile) circuits prepared by postlaser treatment. By means of a laser beam, local graphitization or partial etching of the graphene conductive lines can be achieved to generate conductive areas with different resistances, which can act as flexible and integrated electronic circuits. Besides lightweight conductive circuits, the graphene-coated cotton fabrics were experimentally tested for other technological applications, that is, as flexible metal-free markers or for IR shielding or as nonflammable barriers for the protection of sensitive devices or to prevent flame spreading. This technology allows one to open a new route toward the development of daily life connected and flexible e-textile devices of added value with low carbon footprint impact

Chemically functionalized carbon nanotubes with pyridine groups as easily tunable N-decorated nanomaterials for the oxygen reduction reaction in alkaline medium

We report on the N-decoration of multiwalled carbon nanotubes (MWCNTs) via chemical functionalization under mild reaction conditions. The introduction of tailored pyridinic functionalities as N-containing edge-type group mimics generates effective catalysts for the oxygen reduction reaction (ORR) in an alkaline environment. The adopted methodology lists a number of remarkable technical advantages, among which is an easy tuning of the electronic properties of N-containing groups. The latter aspect further increases the level of complexity for the rationalization of the role of the N-functionalities on the ultimate electrochemical performance of the as-prepared metal-free catalysts. Electrochemical outcomes crossed with the computed electronic charge density distributions on each scrutinized pyridine group have evidenced the central role played by the N-chemical environment on the final catalyst performance. Notably, small variations of the atomic charges on the N-proximal carbon atoms of the chemically grafted heterocycles change the overpotential values at which the oxygen reduction reaction starts. The protocol described hereafter offers an excellent basis for the development of more active metal-free electrocatalysts for the ORR. Finally, the as-prepared catalytically active materials represent a unique model for the in-depth understanding of the underlying ORR mechanism. © 2014 American Chemical Society