150 research outputs found
Antimicrobial Susceptibility Pattern of Clinical Isolates of Escherichia coli and Proteus mirabilis Using Cefepime in Ogbomoso, Nigeria.
The challenge of Cefepime resistance in developing countries is substantial and likely to grow. Emergence of Cefepime-resistant bacteria has increased and managemen
Carbon Dioxide Utilisation -The Formate Route
UIDB/50006/2020 CEEC-Individual 2017 Program Contract.The relentless rise of atmospheric CO2 is causing large and unpredictable impacts on the Earth climate, due to the CO2 significant greenhouse effect, besides being responsible for the ocean acidification, with consequent huge impacts in our daily lives and in all forms of life. To stop spiral of destruction, we must actively reduce the CO2 emissions and develop new and more efficient “CO2 sinks”. We should be focused on the opportunities provided by exploiting this novel and huge carbon feedstock to produce de novo fuels and added-value compounds. The conversion of CO2 into formate offers key advantages for carbon recycling, and formate dehydrogenase (FDH) enzymes are at the centre of intense research, due to the “green” advantages the bioconversion can offer, namely substrate and product selectivity and specificity, in reactions run at ambient temperature and pressure and neutral pH. In this chapter, we describe the remarkable recent progress towards efficient and selective FDH-catalysed CO2 reduction to formate. We focus on the enzymes, discussing their structure and mechanism of action. Selected promising studies and successful proof of concepts of FDH-dependent CO2 reduction to formate and beyond are discussed, to highlight the power of FDHs and the challenges this CO2 bioconversion still faces.publishersversionpublishe
Fullerene C immobilized in polymethylmethacrylate film as an optical temperature sensing material
A new optical temperature sensor based on the fluorescence intensities of the
fullerene C immobilized in polymethylmethacrylate (PMMA) film was developed.
The fluorescence intensity of the C film decreased with increasing the
temperature in the range 260-373 K. Arrhenius plot of ln[ ()]
versus 1/ for the C film exhibits considerable linearity supported by
the correlation factor, , estimated to be 0.989 by the least squares
method ( = 260 K). The value of the C film is estimated to be
22.3 K. These results indicate that the C film provides a linear
temperature response in the range 260-373 K
Optical oxygen sensing based on triplet-triplet decay of platinum octaethylporphyrin-polystyrene film using time-resolved spectroscopy by laser flash photolysis
Optical oxygen sensing system based on the quenching of the photoexcited triplet state of platinum
octaethylporphyrin, PtOEP in polystyrene (PS) by means of time-resolved spectroscopy using laser flash
photolysis has been developed. The decays of the triplet-triplet reflectance of PtOEP in PS consisted of
two components (faster and slower lifetimes) in the absence and presence of oxygen. In both of faster and
slower components, the lifetime decreases with increasing oxygen concentration and a Stern-Volmer plot of
PtOEP-PS film exhibits linearity. However, in faster component is larger than that of slower
component, indicating that two different oxygen-accessible sites exist in PtOEP -PS film. The faster and
slower components are attributed to oxygen-accessible sites on the surface and bulk of PtOEP film,
respectively. The contribution of different oxygen-accessible sites in PtOEP-PS film for oxygen sensing is
clarified by this technique
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