Influence of 1D and 2D carbon fillers and their functionalisation on crystallisation and thermomechanical properties of injection moulded nylon 6,6 nanocomposites

Carbon nanotubes (CNTs) and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation.Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs

A simulation analysis of an influenza vaccine production plant in areas of high humanitarian flow. A preliminary study for the region of norte de santander (colombia)

The production of vaccines of biological origin presents a tremendous challenge for re-searchers. In this context, animal cell cultures are an excellent alternative for the isolation and production of biologicals against several viruses, since they have an affinity with viruses and a great capacity for their replicability. Different variables have been studied to know the system’s ideal parameters, allowing it to obtain profitable and competitive products. Consequently, this work fo-cuses its efforts on evaluating an alternative for producing an anti‐influenza biological from MDCK cells using SuperPro Designer v8.0 software. The process uses the DMEN culture medium supple-mented with nutrients as raw material for cell development; the MDCK cells were obtained from a potential scale‐up with a final working volume of 500 L, four days of residence time, inoculum volume of 10%, and continuous working mode with up to a total of 7400 h/Yr of work. The scheme has the necessary equipment for the vaccine’s production, infection, and manufacture with yields of up to 416,698 units/h. In addition, it was estimated to be economically viable to produce recom-binant vaccines with competitive prices of up to 0.31 USD/unit

All-Optical Fiber Hanbury Brown & Twiss Interferometer to study 1300 nm single photon emission of a metamorphic InAs Quantum Dot

[EN] New optical fiber based spectroscopic tools open the possibility to develop more robust and efficient characterization experiments. Spectral filtering and light reflection have been used to produce compact and versatile fiber based optical cavities and sensors. Moreover, these technologies would be also suitable to study N-photon correlations, where high collection efficiency and frequency tunability is desirable. We demonstrated single photon emission of a single quantum dot emitting at 1300 nm, using a Fiber Bragg Grating for wavelength filtering and InGaAs Avalanche Photodiodes operated in Geiger mode for single photon detection. As we do not observe any significant fine structure splitting for the neutral exciton transition within our spectral resolution (46 mu eV), metamorphic QD single photon emission studied with our all-fiber Hanbury Brown & Twiss interferometer could lead to a more efficient analysis of entangled photon sources at telecom wavelength. This all-optical fiber scheme opens the door to new first and second order interferometers to study photon indistinguishability, entangled photon and photon cross correlation in the more interesting telecom wavelengths.G Munoz-Matutano thanks the Spanish Juan de la Cierva program (JCI-2011-10686). We acknowledge the support of the Spanish MINECO through projects TEC2014-53727-C2-1-R & TEC2014-60378-C2-1-R, the Research Excellency Award Program GVA PROMETEO 2013/012 PROMETEOII/2014/059 and the Explora Ciencia Tecnologia TEC2013-50552-EXP MULTIFUN project, and the Nanoscale Quantum Optics MPNS COST Action MP1403.Muñoz Matutano, G.; Barrera Vilar, D.; Fernandez-Pousa, CR.; Chulia-Jordan, R.; Seravalli. L.; Trevisi, G.; Frigeri, P.... (2016). All-Optical Fiber Hanbury Brown & Twiss Interferometer to study 1300 nm single photon emission of a metamorphic InAs Quantum Dot. Scientific Reports. 6(2721):1-9. https://doi.org/10.1038/srep27214S1962721Walmsley, I. A. Quantum optics: Science and technology in a new light. Science 348, 525–530 (2015).Eisaman, M. D., Fan, J., Migdall, A. & Polyakov, S. Invited review article: single-photon sources and detectors. Rev. Sci. Instrum. 82, 071101 (2011).Lu, C.-L. & Pan, J.-W. Push-button photon entanglement. Nat. Photonics 8, 174–176 (2014).Benson, O., Santori, C., Pelton, M. & Yamamoto, Y. Regulated and entangled photons from a single quantum dot. Phys. Rev. Lett. 84, 2513–2516 (2000).Yuan, Z. et al. Electrically driven single-photon source. Science 295, 102–105 (2002).Salter, C. L. et al. An entangled-light-emitting diode. Nature 465, 594–597 (2010).Brunner, D. et al. A coherent single-hole spin in a semiconductor. Science 325, 70–72 (2009).Müller, M., Bounouar, S., Jöns, K. D., Glässl, M. & Michler, P. On-demand generation of indistinguishable polarization-entangled photon pairs. Nat. Photonics 8, 234–238 (2014).Seguin, R. et al. Size-dependent fine-structure splitting in self-organized InAs/GaAs quantum dots. Phys. Rev. Lett. 95, 257402 (2005).Hadfield, R. H. Single-photon detectors for optical quantum information applications. Nat. Photonics 3, 696–705 (2009).Zinoni, C. et al. Time-resolved and antibunching experiments on single quantum dots at 1300nm. Appl. Phys. Lett. 88, 131102 (2006).Liu, X. et al. Single-photon emission in telecommunication band from an InAs quantum dot grown on InP with molecular-beam epitaxy. Appl. Phys. Lett. 103, 061114 (2013).Benyoucef, M., Yacob, M., Reithmaier, J. P., Kettler, J. & Michler, P. Telecom-wavelength (1.5 μm) single-photon emission from InP-based quantum dots. Appl. Phys. Lett. 103, 162101 (2013).Ward, M. et al. Coherent dynamics of a telecom-wavelength entangled photon source. Nat. Commun. 5, 3316 (2014).Rakher, M. T. et al. Quantum transduction of telecommunications-band single photons from a quantum dot by frequency upconversion. Nat. Photonics 4, 786–791 (2010).Muñoz-Matutano, G. et al. Time resolved emission at 1.3 μm of a single InAs quantum dot by using a tunable fibre Bragg grating. Nanotechnology 25, 035204 (2014).Ediger, M. et al. Peculiar many-body effects revealed in the spectroscopy of highly charged quantum dots. Nature Phys. 3, 774–779 (2007).Gerardot, B. D. et al. Laser spectroscopy of individual quantum dots charged with a single hole. Appl. Phys. Lett. 99, 243112 (2011).Gomis-Bresco, J. et al. Random population model to explain the recombination dynamics in single InAs/GaAs quantum dots under selective optical pumping. New J. Phys. 13, 023022 (2011).Ediger, M. et al. Fine structure of negatively and positively charged excitons in semiconductor quantum dots: electron-hole asymmetry. Phys. Rev. Lett. 98, 036808 (2007).Warming, T. et al. Hole-hole and electron-hole exchange interactions in single InAs/GaAs quantum dots. Phys. Rev. B 79, 125316 (2009).Benny, Y. et al. Excitation spectroscopy of single quantum dots at tunable positive, neutral and negative charge states. Phys. Rev. B 86, 085306 (2012).Muñoz-Matutano, G. et al. Selective optical pumping of charged excitons in unintentionally doped InAs quantum dots. Nanotechnology 19, 145711 (2008).Ha, N. et al. Size-dependent line broadening in the emission spectra of single GaAs quantum dots: Impact of surface charge on spectral diffusion. Phys. Rev. B 92, 075306 (2015).Moskalenko, E. S. et al. Influence of excitation energy on charged exciton formation in self-assembled InAs single quantum dots. Phys. Rev. B 64, 085302 (2001).Rivas, D. et al. Two-color single-photon emission from InAs quantum dots: toward logic information management using quantum light. Nano Lett. 14, 456–463 (2014).Dekel, E. et al. Cascade evolution and radiative recombination of quantum dot multiexcitons studied by time-resolved spectroscopy. Phys. Rev. B 62, 11038 (2000).Wimmer, M., Nair, S. & Shumway, J. Biexciton recombination rates in self-assembled quantum dots. Phys. Rev. B 73, 165305 (2006).Dalgarno, P. A. et al. Coulomb interactions in single charged self-assembled quantum dots: Radiative lifetime and recombination energy. Phys. Rev. B 77, 245311 (2008).Muñoz-Matutano, G. et al. Exciton, biexciton and trion recombination dynamics in a single quantum dot under selective optical pumping. Physica E 40, 2100–2103 (2008).Birkedal, D., Leosson, K. & Hvam, J. M. Long lived coherence in self-assembled quantum dots. Phys. Rev. Lett. 87, 227401 (2001).Tartakovskii, A. et al. Effect of thermal annealing and strain engineering on the fine structure of quantum dot excitons. Phys. Rev. B 70, 193303 (2004).Goldmann, E., Barthel, S., Florian, M., Schuh, K. & Jahnke, F. Excitonic fine-structure splitting in telecom-wavelength InAs/GaAs quantum dots: statistical distribution and height-dependence. Appl. Phys. Lett. 103, 242102 (2004).Seravalli, L., Trevisi, G. & Frigeri, P. 2D–3D growth transition in metamorphic InAs/InGaAs quantum dots. Cryst. Eng. Comm. 14, 1155–1160 (2012).Akimov, I., Kavokin, K., Hundt, A. & Henneberger, F. Electron-hole exchange interaction in a negatively charged quantum dot. Phys. Rev. B 71, 075326 (2005).Brouri, R., Beveratos, A., Poizat, J. & Grangier, P. Photon antibunching in the fluorescence of individual color centers in diamond. Opt. Lett. 25, 1294–1296 (2000).Mandel, L. & Wolf, E. Optical Coherence and Quantum Optics. Cambridge University Press (1995).Seravalli, L., Frigeri, P., Trevisi, G. & Franchi, S. 1.59 μm room temperature emission from metamorphic InAs∕InGaAsInAs∕InGaAs quantum dots grown on GaAs substrates. Appl. Phys. Lett. 92, 213104 (2008).Gonzalez-Tudela, A., Laussy, F. P., Tejedor, C., Hartmann, M. J. & del Valle, E. Two-photon spectra of quantum emitters. New J. Phys. 15, 033036 (2013).Peiris, M. et al. Two-color photon correlations of the light scattered by a quantum dot. Phys. Rev. B 91, 195125 (2015).Venghaus, L. Wavelength Filters in Fibre Optics. Springer Series in Optical Sciences Vol 123 (2006).Seravalli, L. et al. Single quantum dot emission at telecom wavelengths from metamorphic InAs/InGaAs nanostructures grown on GaAs substrates. Appl. Phys. Lett. 98, 173112 (2011).Seravalli, L. et al. Quantum dot strain engineering of InAs∕InGaAsInAs∕InGaAs nanostructures. J. Appl. Phys. 101, 024313 (2007).Seravalli, L., Trevisi, G. & Frigeri, P. Design and growth of metamorphic InAs/InGaAs quantum dots for single photon emission in the telecom window. Crys. Eng. Comm. 14, 6833–6838 (2012).Seravalli, L., Frigeri, P., Nasi, L., Trevisi, G. & Bocchi, C. Metamorphic quantum dots: quite different nanostructures. J. Appl. Phys. 108, 064324 (2010)

Enhancement of metabolite production in high-altitude microalgal strains by optimized C/N/P ratio

This study evaluated the role of C/N/P in the increase in the synthesis of carbohydrates, proteins, and lipids in two high-mountain strains of algae (Chlorella sp. UFPS019 and Desmodesmus sp. UFPS021). Three carbon sources (sodium acetate, sodium carbonate, and sodium bicarbonate), and the sources of nitrogen (NaNO3) and phosphate (KH2PO4 and K2HPO4) were analyzed using a surface response (3 factors, 2 levels). In Chlorella sp. UFPS019, the optimal conditions to enhance the synthesis of carbohydrates were high sodium carbonate content (3.53 g/L), high KH2PO4 and K2HPO4 content (0.06 and 0.14 g/L, respectively), and medium-high NaNO3 (0.1875 g/L). In the case of lipids, a high concentration of sodium acetate (1.19 g/L) coupled with high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively) and a low concentration of NaNO3 (0.075 g/L) drastically induced the synthesis of lipids. In the case of Desmodesmus sp. UFPS021, the protein content was increased using high sodium acetate (2 g/L), high KH2PO4 and K2HPO4 content (0.056 and 0.131 g/L, respectively), and high NaNO3 concentration (0.25 g/L). These results demonstrate that the correct adjustment of the C/N/P ratio can enhance the capacity of high-mountain strains of algae to produce high concentrations of carbohydrates, proteins, and lipids

Parallel Recording of Single Quantum Dot Optical Emission Using Multicore Fibers

(c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.Single Indium Arsenide Quantum Dot emission spectra have been recorded using a four-core, crosstalk-free, multicore fiber placed at the collection arm of a confocal microscope. We developed two different measurement set-ups depending on the relative configuration of the excitation and collection spots. In the single-matched mode, the emission from the excited area is collected by a single core in the multicore fiber, whereas the three remaining cores capture the emission from neighboring, non-excited areas. This procedure allows for the recording of the Quantum Dot emission from carrier diffusion between sample positions separated by more than 6 μm. In the multiple-matched mode, the excitation spot overlaps the four cores emission area. This configuration permits the acquisition of the micro-photoluminescence spectra at different sample positions without scanning. These results show the possibilities offered by multicore fibers for the spectroscopic analysis of single semiconductor Quantum Dot optical emission.This work was supported in part by the Research Excellency Award Program GVA PROMETEO under Grant 2013/012, in part by the Explora Ciencia Tecnologia through the MULTIFUN Project under Grant TEC2013-50552-EXP, in part by the Research Excellency Award Program GVA PROMETEOII under Grant 2014/059, and in part by the Ministerio de Economia y Competitividad under Grant TEC2014-53727-C2-1-R and Grant TEC2014-60378-C2-1-R. The work of G. Munoz-Matutano was supported by the Spanish Ministerio de Economia y Competitividad through the Juan de la Cierva Program under Grant JCI-2011-10686. The work of I. Gasulla was supported by the Spanish Ministerio de Economia y Competitividad through the Ramon y Cajal Program under Grant RyC-2014-16247.Muñoz-Matutano, G.; Barrera Vilar, D.; Fernandez-Pousa, CR.; Chulia-Jordan, R.; Martinez-Pastor, J.; Gasulla Mestre, I.; Seravalli, L.... (2016). Parallel Recording of Single Quantum Dot Optical Emission Using Multicore Fibers. IEEE Photonics Technology Letters. 28(11):1257-1260. https://doi.org/10.1109/LPT.2016.2538302S12571260281

Colloidal Quantum Dots-PMMA Waveguides as Integrable Microwave Photonic Phase Shifters

“© © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.”A novel scheme for the control of microwave signals carried at optical wavelengths by use of PbS colloidal quantum dots embedded in PMMA waveguides is presented. When these structures are pumped at wavelengths where PbS has efficient absorption (980 or 1310 nm), a phase shift in a signal carried at 1550 nm is induced. Optimal conditions have been analyzed by studying the influence of the microwave signal and the waveguide structure. In a proof-of-concept experiment, a continuous phase shift up to 35° at 25 GHz has been demonstrated, with good thermal stability (<2° at 25 GHz) when the samples are heated 20 °C above room temperature. The potential benefits of the use of this active-waveguide technology in microwave photonics are due to the continuous scan of the phase delay, its high tuning speed, and its small size, which leads to the possibility of integration.This work was supported in part by the Infraestructura FEDER under Grants UPVOV08-3E-008 and FEDER UPVOV10-3E-492, in part by the Research Excellency Award Program GVA PROMETEO 2013/012, Next generation Microwave Photonic Technologies, and in part by the Spanish MCINN under Projects TEC2011-29120-C05-01, TEC2011-29120-C05-02, and TEC2011-29120-C05-05.Ricchiuti, AL.; Suárez Álvarez, I.; Barrera Vilar, D.; Rodríguez Cantó, PJ.; Fernandez-Pousa, CR.; Abargues, R.; Sales Maicas, S.... (2014). Colloidal Quantum Dots-PMMA Waveguides as Integrable Microwave Photonic Phase Shifters. IEEE Photonics Technology Letters. 26(4):402-404. https://doi.org/10.1109/LPT.2013.2295253S40240426

Application of Chlorella sp. and Scenedesmus sp. in the bioconversion of urban leachates into industrially relevant metabolites

This paper explores the ability of Chlorella sp. and Scenedesmus sp. to convert landfill leachates into usable metabolites. Different concentrations (0.5, 1, 5, and 10% v/v) of leachate coupled with an inorganic carbon source (Na2CO3, and NaHCO3) were tested to improve biomass production, metabolites synthesis, and removal of NO3 and PO4 . The result shows that both strains can effectively grow in media with up to 5% (v/v) leachate, while significantly reducing the concentrations of NO3, and PO4 (80 and 50%, respectively). The addition of NaHCO3 as a carbon source improved the final concentration of biomass, lipids, carbohydrates, and the removal of NO3 and PO4 in both strains

Removal of nutrients and pesticides from agricultural runoff using microalgae and cyanobacteria

The use of pesticides in agriculture has ensured the production of different crops. However, pesticides have become an emerging public health problem for Latin American countries due to their excessive use, inadequate application, toxic characteristics, and minimal residue control. The current project evaluates the ability of two strains of algae (Chlorella and Scenedesmus sp.) and one cyanobacteria (Hapalosyphon sp.) to remove excess pesticides and other nutrients present in runoff water from rice production. Different concentrations of wastewater and carbon sources (Na2CO3 and NaHCO3 ) were evaluated. According to the results, all three strains can be grown in wastewater without dilution (100%), with a biomass concentration comparable to a synthetic medium. All three strains significantly reduced the concentration of NO3 and PO4 (95 and 85%, respectively), with no difference between Na2CO3 or NaHCO3 . Finally, Chlorella sp. obtained the highest removal efficiency of the pesticide (Chlorpyrifos), followed by Scenedesmus and Hapalosyphon sp. (100, 75, and 50%, respectively). This work shows that it is possible to use this type of waste as an alternative source of nutrients to obtain biomass and metabolites of interest, such as lipids and carbohydrates, to produce biofuels

CUPID-0: the first array of enriched scintillating bolometers for 0decay investigations

The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of82Se neutrinoless double-beta decay (0). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0at the level of 10- 3 counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn82Se scintillating bolometers coupled with bolometric light detectors, with a state of the art technology for background suppression and thorough protocols and procedures for the detector preparation and construction. In this paper, the different phases of the detector design and construction will be presented, from the material selection (for the absorber production) to the new and innovative detector structure. The successful construction of the detector lead to promising preliminary detector performance which is discussed here

A simulation analysis of a microalgal-production plant for the transformation of inland-fisheries wastewater in sustainable feed

The present research evaluates the simulation of a system for transforming inland-fisheries wastewater into sustainable fish feed using Designer® software. The data required were obtained from the experimental cultivation of Chlorella sp. in wastewater supplemented with N and P. According to the results, it is possible to produce up to 11,875 kg/year (31.3 kg/d) with a production cost of up to 18 (USD/kg) for dry biomass and 0.19 (USD/bottle) for concentrated biomass. Similarly, it was possible to establish the kinetics of growth of substrate-dependent biomass with a maximum production of 1.25 g/L after 15 days and 98% removal of available N coupled with 20% of P. It is essential to note the final production efficiency may vary depending on uncontrollable variables such as climate and quality of wastewater, among others