14 research outputs found

    Bimetallic palladium-cobalt nanomaterials as highly efficient catalysts for dehydrocoupling of dimethylamine borane

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    In this work, we report the synthesis, characterization and application of graphene oxide stabilized PdCo nanoparticles (PdCo@GO) for the dehydrocoupling of dimethylamine borane (DMAB) as a model reaction. Bimetallic graphene oxide stabilized PdCo nanoparticles were readily synthesized using an ultrasonic reduction technique, in which both metals of Pd and Co were reduced with GO. The dispersion of PdCo nanoparticles on the surface of GO was enhanced with the help of the ultrasonic reduction method which result in the enhancing of dispersion of both metals without any agglomeration problem. The characterization studies revealed that graphene oxide stabilized PdCo nanoparticles have a uniform, homogeneous distribution on graphene oxide and an average particle size of 3.48 ± 0.22 nm. After fully characterization of graphene oxide stabilized PdCo nanoparticles, they have been tried in model reaction as a catalyst and exhibited a high catalytic performance compared the previous catalysts in literature with a TOF value of 226.80 h-1. The investigation of kinetic parameters showed that graphene oxide stabilized PdCo nanoparticles have very high negative entropy (?S: -170.85 J mol-1 K-1) value and a low activation energy value (Ea: 17.53 ± 2 kJ mol-1) for the model reaction. © 2019 Hydrogen Energy Publications LLC2014-05The authors would like to thank Kutahya Dumlupinar University ( 2014-05 ) for financial support. Appendix

    Binary Palladium–Nickel/Vulcan carbon-based nanoparticles as highly efficient catalyst for hydrogen evolution reaction at room temperature

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    Herein, Palladium–Nickel alloy nanoparticles assembled on Vulcan carbon composites (PdNi@VC) have been reported as highly efficient, stable and durable catalyst for the hydrogen evolution from dimethylamine borane. Palladium–Nickel alloy nanoparticles assembled on Vulcan carbon composites were prepared using ultrasonic reduction technique and characterized using some analytical methods. The characterization analyses revealed that Palladium–Nickel alloy nanoparticles assembled on Vulcan carbon composites have a monodisperse metal distribution and crystalline structure. Some catalytic experiments were performed, and some activation parameters such as activation energy (Ea=40.05 ± 2 kJ/mol), activation entropy (?S =-132.11± 1 J mol-1 K-1) and activation enthalpy (?H =37.55 ± 1 kJ mol-1) were calculated for catalytic reaction of dimethylamine borane. The turnover frequency (TOF) value of Palladium–Nickel alloy nanoparticles assembled on Vulcan carbon composites was found to be 283.48 h-1, having one of the best catalytic activities among the previous heterogenous catalysts tested for dimethylamine borane (DMAB) catalytic reaction. © 2019 Taiwan Institute of Chemical Engineer

    Epidemiology and distribution of interstitial lung diseases in Turkey

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    Introduction: There is very few data on the epidemiological features of interstitial lung diseases (ILD) in the literature. These studies on this subject suffer from limited number of patients. Objective: The goal of this study was to evaluate the epidemiological features of ILD in Turkey. Methods: Fifty-four investigators, 31 centres in 19 cities from six regions of Turkey, participated in the study. Two thousand two hundred forty-five newly diagnosed patients (51.8% females), led by Turkish Thoracic Society Clinical Problems Study Group, enrolled in this prospective study. Results: The mean age was 51.8±16.7 years. The mean age among males was 50.5±18.6 years and 53.0±14.6 years among females (P<0.001). 23.8% of the cases had ILD with known causes, while 39.4% were in granulomatous group, 23.7% were idiopathic, and 4.4% were in the unclassified group. Overall, histopathologically confirmed diagnosis rate was 40.4%. Sarcoidosis was the most common disease (37%), whereas cases with idiopathic pulmonary fibrosis (IPF) constituted 19,9% of patients. 53% of the sarcoidosis patients were females, and the ratio reaches to 75% under 50 years of age (for this group, IPF ratio is %3). In contrast, sarcoidosis and IPF ratios were equal in males (25%). Sarcoidosis was 8% in men over 50, while IPF was %45. Conclusion: The overall incidence of ILD in Turkey was computed to be 25.8/100000. © 2013 John Wiley & Sons Ltd

    High morbidity during treatment and residual pulmonary disability in pulmonary tuberculosis: under-recognised phenomena

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    Background: In pulmonary tuberculosis (PTB), morbidity during treatment and residual pulmonary disability can be under-estimated.\ud \ud Methods: Among adults with smear-positive PTB at an outpatient clinic in Papua, Indonesia, we assessed morbidity at baseline and during treatment, and 6-month residual disability, by measuring functional capacity (six-minute walk test [6MWT] and pulmonary function), quality of life (St George's Respiratory Questionnaire [SGRQ]) and Adverse Events ([AE]: new symptoms not present at outset). Results were compared with findings in locally-recruited volunteers.\ud \ud Results: 200 PTB patients and 40 volunteers were enrolled. 6WMT was 497m (interquartile range 460-529) in controls versus 408m (IQR 346-450) in PTB patients at baseline (p<0.0001) and 470m (IQR 418-515) in PTB patients after 6 months (p=0.02 versus controls). SGRQ total score was 0 units (IQR 0-2.9) in controls, versus 36.9 (27.4-52.8) in PTB patients at baseline (p<0.0001) and 4.3 (1.7-8.8) by 6 months (p<0.0001). Mean percentage of predicted FEV1 was 92% (standard deviation 19.9) in controls, versus 63% (19.4) in PTB patients at baseline (p<0.0001) and 71% (17.5) by 6 months (p<0.0001). After 6 months, 27% of TB patients still had at least moderate-severe pulmonary function impairment, and 57% still had respiratory symptoms, despite most achieving 'successful' treatment outcomes, and reporting good quality of life. More-advanced disease at baseline (longer illness duration, worse baseline X-ray) and HIV positivity predicted residual disability. AE at any time during treatment were common: itch 59%, arthralgia 58%, headache 40%, nausea 33%, vomiting 16%.\ud \ud Conclusion: We found high 6-month residual pulmonary disability and high AE rates. Although PTB treatment is highly successful, the extent of morbidity during treatment and residual impairment could be overlooked if not specifically sought. Calculations of PTB-related burden of disease should acknowledge that TB-related morbidity does not stop at 6 months. Early case detection and treatment are key in minimising residual impairment
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