Evaluation of oxygen carriers based on manganese-iron mixed oxides prepared from natural ores or industrial waste products for chemical looping processes

Manganese-iron mixed oxides have been identified as promising oxygen carrier materials in chemical looping processes. In this work, low-cost raw materials are considered for the production of this type of oxygen carrier. Four manganese based minerals from deposits of different locations – South Africa, Gabon(x2) and Brazil – and two iron based materials (Fe-ore from Spain and Redmud waste) were used to prepare suitable oxygen carriers through a new two-step production method: a mixing-grinding (about 5 µm) pre-treatment followed by pelletizing, crushing and sieving to produce particles of the desired size (100–300 µm). This method was required in order to form the MnFe mixed oxide and to provide permanent magnetic properties, which were not found when the oxygen carriers were prepared by the classical one-step method, i.e. crushing and sieving of raw materials to the desired particle size (100–300 µm). The oxygen uncoupling capability of the developed materials was extremely low and even completely lost after repeated redox cycles. However, they were reactive under chemical looping conditions with H2, CO and CH4. Reactivity varied with the raw materials used and with the redox cycles, being of crucial importance for its evolution the intensity of the chemical stress during hundreds of redox cycles. © 2022 The Author

Analysis of Fiber optic sensor embedding in metals by automatic and manual TIG welding

In this paper, the embedding of fiber optic sensors in metals, by using both automatic and manual Tungsten Inert Gas welding (TIG) is discussed for nickel- and copper-coated Fiber Bragg Gratings (FBG) written into an optical fiber, as embedding such sensors in metals provides protection against environmental effects. In the investigation and analysis of the performance of a number of such sensors, copper-coated sensors were seen to lose their temperature and strain sensitivity while being embedded due to damage to the coating, while with a nickel coating the sensors in the fiber were found to withstand the process with a lesser effect on the sensor performance. The research has also shown that the Automatic TIG process used is less invasive than the manual TIG approach, although more expensive to implement

Laser Cladding-based metallic embedding technique for fiber optic sensors

IEEE In many applications in industry, securely attaching fiber optic sensors to metallic structures is important for optimum monitoring, overcoming the limitations of glues and adhesives which are known to degrade under certain circumstances. To avoid that problem, creating a metallic bond to attach the sensors securely to the metal surface is important. Commercial fiber optics with metal coatings can be used but it is important not to damage the sensor itself which is written in the thin optical fiber. In this work an alternative laser cladding technology has been studied for embedding metal coated fiber optics into which Fiber Bragg Grating (FBG) sensors have been written. A three-step strategy was selected for embedding the metal coating fibers to create the best conditions to allow high quality measurements to be made. This has been seen to allow good control of the embedding process to be achieved and to minimize the thermal and mechanical stress generated. The research undetaken has shown that it is possible to embed Cu and Ni coated fiber optics containing sensors to over 300 & #x03BC;m with low losses, of between 0-1.5 dB (or 0-30%) and yet still enable satisfactory strain and temperature measurement results to be obtained. The research has shown that both Ni and Cu coated FBG-based fiber optic sensors could be embedded successfully and shown to give good mechanical and thermal response to similar non-embedded sensors and give excellent cross-comparison with the conventional gauge used for calibration. The results are therefore particularly encouraging for the use of sensors of this type when incorporated to create metallic & #x2018;smart structures & #x2019; achieving durability of the sensors through the use of this innovative technique

Interpenetrated polymer networks of Poly(β-cyclodextrin) and Polyvinylpyrrolidone with synergistic and selective sorption capacities

Interpenetrating polymer network (IPN) hydrogels were synthesised using β-cyclodextrin (β-CD) and N-vynil-2-pyrrolidone (NVP) crosslinked with epichlorohydrin and divinylbenzene, respectively, and prepared by four different procedures: simultaneous, sequential, hybrid and a novel one named hybrid-sequential. The IPNs prepared have been characterised by infrared spectroscopy and thermal analysis. The equilibrium swelling in water and the sorption of model substances into the IPNs have also been studied. The model sorbates (1-naphthol, 2-acetylnaphthalene and tannic acid) were selected according to the affinities towards each one of the two constituent polymers. Our studies reveal that these IPNs can be applied for the sorption of substances that can interact with the network by two mechanisms, i.e. inclusion within cyclodextrin cavities and/or via specific interactions with the functional groups present. Besides, due to the complementary character of their constituent polymers, these networks could also serve to retain two substances of different nature such as cetirizine and pseudoephedrine

Placental fatty acid transfer: a key factor in fetal growth

The functionality of the placenta may affect neonatal adiposity and fetal levels of key nutrients such as long-chain polyunsaturated fatty acids. Fetal macrosomia and its complications may occur even in adequately controlled gestational diabetic (GDM) mothers, suggesting that maternal glycemia is not the only determinant of fetal glycemic status and wellbeing. We studied in vivo the placental transfer of fatty acids (FA) labeled with stable isotopes administered to 11 control and 9 GDM pregnant women (6 treated with insulin). Subjects received orally &lt;sup&gt;13&lt;/sup&gt;C-palmitic, &lt;sup&gt;13&lt;/sup&gt;C-oleic, and &lt;sup&gt;13&lt;/sup&gt;C-linoleic acids and &lt;sup&gt;13&lt;/sup&gt;C-docosahexaenoic acid (&lt;sup&gt;13&lt;/sup&gt;C-DHA) 12 h before an elective caesarean section. FA were quantified by gas chromatography and &lt;sup&gt;13&lt;/sup&gt;C enrichments by gas chromatography-isotope ratio mass spectrometry. The &lt;sup&gt;13&lt;/sup&gt;C-FA concentration was higher in total lipids of maternal plasma in GDM patients versus controls, except for &lt;sup&gt;13&lt;/sup&gt;C-DHA. Moreover, &lt;sup&gt;13&lt;/sup&gt;C-DHA showed a lower placenta/maternal plasma ratio in GDM patients versus controls and a significantly lower cord/maternal plasma ratio. Other FA ratios studied were not different between GDM and controls. A disturbed &lt;sup&gt;13&lt;/sup&gt;C-DHA placental uptake occurred in GDM patients treated with diet or insulin, while the latter also had lower &lt;sup&gt;13&lt;/sup&gt;C-DHA levels in the venous cord. The tracer study pointed towards an impaired placental DHA uptake as a critical step, while the transfer of other &lt;sup&gt;13&lt;/sup&gt;C-FA was less affected. Patients with GDM treated with insulin could also have a greater fetal fat storage, which may have contributed to the reduced &lt;sup&gt;13&lt;/sup&gt;C-DHA in the venous cord observed. The DHA transfer to the fetus was reduced in GDM pregnancies compared to controls. This might have an influence on fetal neurodevelopment and long-term consequences for the child.</jats:p

The polo-like kinase 1 (PLK1) inhibitor NMS-P937 is effective in a new model of disseminated primary CD56+ acute monoblastic leukaemia

CD56 is expressed in 15–20% of acute myeloid leukaemias (AML) and is associated with extramedullary diffusion, multidrug resistance and poor prognosis. We describe the establishment and characterisation of a novel disseminated model of AML (AML-NS8), generated by injection into mice of leukaemic blasts freshly isolated from a patient with an aggressive CD56+ monoblastic AML (M5a). The model reproduced typical manifestations of this leukaemia, including presence of extramedullary masses and central nervous system involvement, and the original phenotype, karyotype and genotype of leukaemic cells were retained in vivo. Recently Polo-Like Kinase 1 (PLK1) has emerged as a new candidate drug target in AML. We therefore tested our PLK1 inhibitor NMS-P937 in this model either in the engraftment or in the established disease settings. Both schedules showed good efficacy compared to standard therapies, with a significant increase in median survival time (MST) expecially in the established disease setting (MST = 28, 36, 62 days for vehicle, cytarabine and NMS-P937, respectively). Importantly, we could also demonstrate that NMS-P937 induced specific biomarker modulation in extramedullary tissues. This new in vivo model of CD56+ AML that recapitulates the human tumour lends support for the therapeutic use of PLK1 inhibitors in AML

Diversity of culturable nocardioform actinomycetes from wastewater treatment plants in Spain and their role in the biodegradability of aromatic compounds

[EN] Currently, municipal and industrial wastewater treatment plants (WWTPs) are mainly focusing on reduction of biological oxygen demand and on the removal of nutrients. However, there are microorganisms that interfere with the process. In this environment, there is a large diversity of microorganisms that have not been studied in detail and that could provide real and practical solutions to the foaming problems. Among such microorganisms, Gram-positive actinomycete bacteria are of special interest because they are known for producing secondary metabolites as well as chemically diverse compounds and for their capacity to degrade recalcitrant pollutants. Three different media were chosen to isolate actinomycetes from 28 WWTPs in Spain. A total of 189 activated sludge samples were collected; 126 strains were isolated and identified to belong to 1 suborder, i.e. Corynebacterineae, and 7 genera, i.e. Corynebacterium, Dietzia, Gordonia, Mycobacterium, Rhodococcus, Tsukamurella and Williamsia. Furthermore, 71 strains were capable of biodegrading at least 1 aromatic product, and that 27 of them amplified for catA gene. The results of this research help us understand the complexity of the foam-forming microbial populations in Spain and it shows that WWTPs can be a good source of microorganisms that can degrade phenol or naphthalene.This work was supported by grants from Entidad Publica de Saneamiento de Aguas Residuales (EPSAR) de la Comunitat Valenciana.Soler Hernández, A.; García Hernández, J.; Zornoza-Zornoza, AM.; Alonso Molina, JL. (2017). Diversity of culturable nocardioform actinomycetes from wastewater treatment plants in Spain and their role in the biodegradability of aromatic compounds. Environmental Technology. 39(2):172-181. https://doi.org/10.1080/09593330.2017.1296897S17218139

Limits on the high-energy gamma and neutrino fluxes from the SGR 1806-20 giant flare of December 27th, 2004 with the AMANDA-II detector

On December 27th 2004, a giant gamma flare from the Soft Gamma-ray Repeater 1806-20 saturated many satellite gamma-ray detectors. This event was by more than two orders of magnitude the brightest cosmic transient ever observed. If the gamma emission extends up to TeV energies with a hard power law energy spectrum, photo-produced muons could be observed in surface and underground arrays. Moreover, high-energy neutrinos could have been produced during the SGR giant flare if there were substantial baryonic outflow from the magnetar. These high-energy neutrinos would have also produced muons in an underground array. AMANDA-II was used to search for downgoing muons indicative of high-energy gammas and/or neutrinos. The data revealed no significant signal. The upper limit on the gamma flux at 90% CL is dN/dE < 0.05 (0.5) TeV^-1 m^-2 s^-1 for gamma=-1.47 (-2). Similarly, we set limits on the normalization constant of the high-energy neutrino emission of 0.4 (6.1) TeV^-1 m^-2 s^-1 for gamma=-1.47 (-2).Comment: 14 pages, 3 figure

The Antares Collaboration : Contributions to the 34th International Cosmic Ray Conference (ICRC 2015, The Hague)

The ANTARES detector, completed in 2008, is the largest neutrino telescope in the Northern hemisphere. Located at a depth of 2.5 km in the Mediterranean Sea, 40 km off the Toulon shore, its main goal is the search for astrophysical high energy neutrinos. In this paper we collect the 21 contributions of the ANTARES collaboration to the 34th International Cosmic Ray Conference (ICRC 2015). The scientific output is very rich and the contributions included in these proceedings cover the main physics results, ranging from steady point sources, diffuse searches, multi-messenger analyses to exotic physics