Microwave-assisted lignin wet peroxide oxidation to C4 dicarboxylic acids

Innovative methodologies, such as microwaveassisted reaction, can help to valorize lignin with higher productivity and better energy efficiency. In this work, microwave heating was tested in the wet peroxide oxidation of three lignins (Indulin AT, Lignol, and Eucalyptus globulus lignins) as a novel methodology to obtain C4 dicarboxylic acids. The effect of temperature, time, and catalyst type (TS-1 or Fe-TS1) was evaluated in the production of these acids. The TS-1 catalyst improved succinic acid yield, achieving up to 9.4 wt % for Lignol lignin. Moreover, the microwave heating specifically enhanced Lignol conversion to malic acid (34 wt %), even without catalyst, showing to be an attractive path for the future valorization of organosolv lignins. Overall, compared to conventional heating, microwave heating originated a rapid lignin conversion. Nevertheless, for prolonged times, conventional heating led to better results for some target products, e.g., malic and succinic acids.This work was financially supported by Base Funding UIDB/50020/2020 of the Associate Laboratory LSRE-LCM funded by national funds through FCT/MCTES (PIDDAC); Base Funding UIDB/00690/2020 of CIMO-Centro de Investigação de Montanha funded by national funds through FCT/MCTES (PIDDAC). COST Action LignoCOST (CA17128). C.A.V.-A. thanks the Costa Rican Science, Technology and Telecommunications Ministry for the Ph.D. Scholarship MICITT-PINN-CON-2-1-4-17-1-002. The authors thank Dr. Maria José Sampaio and Prof. Dr. Joaquim Faria (LA LSRE-LCM) for the help with the FTIR measurements.info:eu-repo/semantics/publishedVersio

Novel functionalised imidazo-benzocrown ethers bearing a thiophene spacer as fluorimetric chemosensors for metal ion detection

Novel phenylalanine derivatives bearing benzimidazole and crown ethers as coordinating/reporting units and thiophene as a spacer unit were synthesized for the first time, and their evaluation as fluorimetric chemosensors was carried out in acetonitrile and acetonitrile/water solutions. 15-Crown-5 benzimidazolyl phenylalanine methyl ester, 15-crown-5 thienylbenzimidazolyl phenylalanine methyl ester and 18-crown-6 thienylbenzimidazolyl phenylalanine methyl ester were tested for alkaline, alkaline-earth and transition metal ions (such as Na+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg2+, Ni2+, Pd2+ and Zn2+). The different crown ether binding moieties as well as the electronic nature and the length of the π-bridge linked to the benzimidazole heterocycle allowed the fine tuning of the sensory properties as seen by spectrofluorimetric titrations. Therefore, 15-crown-5 benzimidazolyl phenylalanine methyl ester is a fluorimetric chemosensor, being selective and sensitive for Cu2+ and Pd2+ in aqueous solutions (ACN/H2O; 80:20). On the other hand, the metal cation sensing properties displayed by 15-crown-5 thienylbenzimidazolyl phenylalanine methyl ester bearing an arylthienyl spacer showed that this is a promising candidate as fluorimetric chemosensor for Fe3+, Pb2+ and Pd2+ in acetonitrile solution.Thanks are due to Fundação para a Ciência e Tecnologia (Portugal) for financial support to the Portuguese NMR network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER (European Fund for Regional Development)-COMPETEQREN-EU for financial support to the research centre CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302], a PhD grant to C.I.C. Esteves (SFRH/BD/68360/2010) and a post-doctoral grant to R.M.F. Batista (SFRH/BPD/79333/2011).info:eu-repo/semantics/publishedVersio

Polyaniline coated conducting fabrics : chemical and electrochemical characterization

Polyaniline coated conducting fabrics have been obtained by chemical oxidation of aniline by potassium peroxydisulfate on polyester fabrics. Two different acids have been employed to carry out the synthesis (HCl and H2SO4), obtaining the best results of conductivity with the latter one. The conducting fabrics have been characterized chemically by means of Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), energy dispersive X-Ray (EDX) and X-ray photoelectron spectroscopy (XPS). The morphology of the coatings has been observed by means of scanning electron microscopy (SEM). The conducting properties of the fabrics have been measured by means of electrochemical impedance spectroscopy (EIS). The electrochemical characterization has been carried out by means of cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM). The conducting fabrics have also shown electrochromic properties, changing its color from green yellowish at −1 V to dark green at +2 V. The durability of the coating has been evaluated by means of washing and rubbing fastness tests.Authors thank to the Spanish Ministerio de Ciencia e Innovacion and European Union Funds (FEDER) (contract CTM2010-18842-C02-02) and Universitat Politecnica de Valencia (Primeros Proyectos de Investigacion (PAID-06-10)) for the financial support. J. Molina is grateful to the Conselleria d'Educacio (Generalitat Valenciana) for the FPI fellowship

Doença emaciante crónica dos cervídeos- Qual o risco em Portugal?

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Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362