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We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.
RESUMEN
We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.
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Activated hydrochars obtained from the hydrothermal carbonization of orange peels (Citrus sinensis) followed by various thermochemical processing were assessed as adsorbents for emerging contaminants in water. Thermal activation under flows of CO2 or air as well as chemical activation with phosphoric acid were applied to the hydrochars. Their characteristics were analyzed and related to their ability to uptake three pharmaceuticals (diclofenac sodium, salicylic acid and flurbiprofen) considered as emerging contaminants. The hydrothermal carbonization and subsequent activations promoted substantial chemical transformations which affected the surface properties of the activated hydrochars; they exhibited specific surface areas ranging from 300 to â¼620 m(2)/g. Morphological characterization showed the development of coral-like microspheres dominating the surface of most hydrochars. Their ability to adsorb the three pharmaceuticals selected was found largely dependent on whether the molecules were ionized or in their neutral form and on the porosity developed by the new adsorbents.
Asunto(s)
Carbón Orgánico/química , Citrus/química , Residuos , Contaminantes Químicos del Agua/aislamiento & purificación , Agua/química , Adsorción , Diclofenaco/aislamiento & purificación , Cinética , Modelos Teóricos , Nitrógeno/química , Compuestos Orgánicos , Ácido Salicílico/química , TemperaturaRESUMEN
Activated carbons from two species of pine cones (Pinus canariensis and Cupressus sempervirens) were prepared by phosphoric acid activation and tested for the removal of nitrate ions from aqueous solution. To investigate the feasibility of improving their nitrate adsorption capacity, two different post-treatmentsa thermal treatment and a treatment with saturated urea solutionwere also applied to the prepared activated carbons. Comparison of the treated and untreated activated carbons showed that both post-treatments improved the nitrate adsorption performance more than twice. The maximum adsorption capacity, as evaluated from determination of the adsorption isotherms for the P. canariensis based carbons, and their proper representation by the Langmuir model, demonstrated that the post-treatment with the urea solution led to activated carbons with increased nitrate removal effectiveness, even superior to other reported results. Enhancements in their adsorption capacity could be mainly ascribed to higher contents of nitrogen and basic functional groups, whereas porous structure of the activated carbons did not seem to play a key role in the nitrate uptake.
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Carbono/metabolismo , Nitratos/metabolismo , Pinus/metabolismo , AdsorciónRESUMEN
A simple alkaline pre-treatment of Cupressus sempervirens cone chips was performed to improve their biosorption capacity towards methylene blue and rhodamine B from aqueous solutions, in batch and continuous modes. Biosorption kinetics were determined from single and binary dyes solutions, and properly described by the pseudo-second-order rate model. Experimental single-dye equilibrium isotherms fitted the Langmuir-Freundlich model, with maximum biosorption capacities of 0.68mmol/g for methylene blue and 0.50mmol/g for rhodamine B. Single-dye dynamic biosorption showed that breakthrough time for methylene blue biosorption was almost four times longer than for rhodamine B and that the alkaline modification of the chips greatly improved the biosorption performance. Competitive dynamic biosorption demonstrated the preference of the modified cone chips for biosorbing methylene blue, confirmed by the exit concentration overshoots obtained in the breakthrough curves of rhodamine B.
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Técnicas de Cultivo Celular por Lotes/métodos , Colorantes/aislamiento & purificación , Cupressus/química , Hidróxidos/farmacología , Compuestos de Potasio/farmacología , Residuos/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción/efectos de los fármacos , Biodegradación Ambiental/efectos de los fármacos , Cupressus/efectos de los fármacos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Cinética , Azul de Metileno/aislamiento & purificación , Modelos Químicos , Rodaminas/aislamiento & purificación , Soluciones , TemperaturaRESUMEN
The feasibility of using cypress cone chips from Cupressus sempervirens as a low-cost biosorbent for the removal of two representative basic dyes, methylene blue (MB) and rhodamine B (RhB), from aqueous solutions was investigated in batch and continuous modes. Dyes biosorption was strongly dependent on the solution's pH. Sorption kinetics was determined and properly described by the pseudo-second-order rate model. Experimental equilibrium isotherms fitted the Langmuir model, showing maximum biosorption capacities of 0.62 mmol/g for MB and 0.24 mmol/g for RhB. Competitive experiments from a binary solution of the dyes demonstrated the preference of the cone chips for biosorbing MB. Very low desorption efficiencies were obtained for both dyes. Dynamic experiments showed that the breakthrough time was three times higher for MB biosorption than for RhB for the same conditions. Breakthrough curves were properly represented by a mathematical model.
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Colorantes/aislamiento & purificación , Cupressus/anatomía & histología , Cupressus/metabolismo , Purificación del Agua/métodos , Adsorción , Biodegradación Ambiental , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno/aislamiento & purificación , Modelos Químicos , Rodaminas/aislamiento & purificación , Soluciones , TemperaturaRESUMEN
Activated carbon cloths (ACC) were prepared from lyocell, a novel regenerated cellulose nanofibre fabric, by phosphoric acid activation in inert atmosphere at two different final thermal treatment temperatures (864 and 963 degrees C). Benzene, toluene and n-hexane isotherms at 298 and 273K were measured in order to gain insight into the porous structure of the ACC and to evaluate their performance for the removal of volatile organic compounds (VOCs). The Dubinin-Radushkevich equation was employed to evaluate textural parameters of the ACC. The textural characteristics of the ACC were compared with those previously determined from nitrogen (77K) and carbon dioxide (273K) adsorption data. The samples were essentially microporous. The textural parameters calculated from the hydrocarbon isotherms were in good agreement with those evaluated from nitrogen isotherms for the ACC with the wider microporosity. Additionally, the Freundlich model provided a good description of the experimental isotherms for the three volatile organic compounds. The ACC obtained at the higher temperature exhibited a larger adsorption capacity. The ACC were also electrically conductive and showed potential for regeneration by the Joule effect, as determined from macroscopic electrical measurements before and after n-hexane adsorption.
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Celulosa/química , Carbón Orgánico/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Adsorción , Contaminantes Atmosféricos/aislamiento & purificación , Conservación de los Recursos Naturales , TemperaturaRESUMEN
An industrial raw Kraft lignin was investigated to ascertain its potential use for removal of trace Ni(II) ion from wastewater by using dilute solutions (0.34-1.7 mM) as models. The effect of demineralisation on its metal sorption ability was examined by employing acid pre-treated samples. Under fixed pre-established equilibrium conditions, the raw lignin exhibited a lower effectiveness than the demineralised one, with the latter attaining an almost complete removal of Ni(II) ions. For both lignins, sorption kinetics was properly described by a pseudo-second order rate model. Equilibrium isotherms were also determined and adequately represented by conventional two-parameter models. The higher nickel sorption capacity for the demineralised lignin compared to the raw sample was consistent with enhancements in the negative magnitude of zeta potential, sodium sorption capacity, and content of phenolic hydroxyl groups occasioned by the acid pre-treatment. Accordingly, demineralisation appears as a readily convenient strategy to improve the behaviour of industrial Kraft lignin for potential use as a biosorbent of trace nickel from polluted water.
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Lignina/química , Minerales/química , Modelos Químicos , Níquel/química , Níquel/aislamiento & purificación , Ultrafiltración/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Absorción , Simulación por Computador , Estudios de Factibilidad , Contaminantes Químicos del Agua/químicaRESUMEN
Activated carbons were developed by phosphoric acid activation of sawdust from Prosopis ruscifolia wood, an indigenous invasive species of degraded lands, at moderate conditions (acid/precursor ratio=2, 450 degrees C, 0.5h). For in situ modification of their characteristics, either a self-generated atmosphere or flowing air was used. The activated carbons developed in the self-generated atmosphere showed higher BET surface area (2281m2/g) and total pore volume (1.7cm3/g) than those obtained under flowing air (1638m2/g and 1.3cm3/g). Conversely, the latter possessed a higher total amount of surface acidic/polar oxygen groups (2.2meq/g) than the former (1.5meq/g). To evaluate their metal sorption capability, adsorption isotherms of Cu(II) ion from model solutions were determined and properly described by the Langmuir model. Maximum sorption capacity (Xm) for the air-derived carbons (Xm=0.44mmol/g) almost duplicated the value for those obtained in the self-generated atmosphere (Xm=0.24mmol/g), pointing to a predominant effect of the surface functionalities on metal sequestering behaviour. The air-derived carbons also demonstrated a superior effectiveness in removing Cd(II) ions as determined from additional assays in equilibrium conditions. Accordingly, effective phosphoric acid-activated carbons from Prosopis wood for toxic metals removal from wastewater may be developed by in situ modification of their characteristics operating under flowing air.
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Carbono/análisis , Carbono/química , Metales/análisis , Prosopis/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Madera/química , Metales/toxicidad , Modelos Químicos , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
The formation of a novel interpolyelectrolyte complex (IPEC) between basic butylated methacrylate copolymer and kappa-carrageenan was investigated and the product formed was characterized. Turbidity measurements and elemental analyses pointed to a 1:1 interaction of the repeating units. These results and FT-IR confirmed IPEC formation. Electronic microscopy images, particle size determination by image analysis and N(2) (77K) adsorption measurements were consistent with a porous material. This IPEC formed presented very good flowability and compactibility. Two maxima were observed in the swelling behaviour as a function of pH. The performance of the IPEC as a matrix for controlled release of drugs was evaluated, using ibuprofen as a model drug. Release profiles were properly represented by a mathematical model, which indicates that the system releases ibuprofen in a zero-order manner. These profiles could be controlled by conveniently modifying the proportion of the IPEC in the tablets.
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Antiinflamatorios no Esteroideos/química , Carragenina/síntesis química , Portadores de Fármacos , Ibuprofeno/química , Ácidos Polimetacrílicos/síntesis química , Química Farmacéutica , Preparaciones de Acción Retardada , Composición de Medicamentos , Concentración de Iones de Hidrógeno , Cinética , Modelos Químicos , Tamaño de la Partícula , Porosidad , Solubilidad , Propiedades de Superficie , Comprimidos , Tecnología Farmacéutica/métodosRESUMEN
Three biomass, birch wood Betula sp., marine brown alga Fucus vesiculosus, and terrestrial moss Pleurozium schreberi, have been compared as raw materials for preparation of biosorbents for removal of copper ions from diluted water solutions. Small sample doses (0.5 g/100ml) of the biosorbents prepared from alga and moss enabled more than 90% removal of Cu(II) ions from diluted water solutions (5-20mg/l). The sample from sawdust was less effective. A pseudo-second-order rate model properly described the experimental kinetic data for the biosorbents. The maximum sorption capacities (Xm) determined from the experimental equilibrium isotherms by applying the Langmuir model showed that the alga had the best copper-binding ability (Xm=23.4 mg/g), followed by the moss (Xm=11.1mg/g), and the sawdust (Xm=4.9 mg/g). No visible damages or performance losses were detected for the alga and moss after five sorption-desorption cycles using diluted HCl as eluent.
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Biomasa , Briófitas/metabolismo , Cobre/metabolismo , Fucus/metabolismo , Madera , CinéticaRESUMEN
Canes from Arundo donax, a herbaceous rapid-growing plant, were used as precursor for activated carbon preparation by phosphoric acid activation under a self-generated atmosphere. The influence of the carbonization temperature in the range 400-550 degrees C and of the weight ratio phosphoric acid to precursor (R = 1.5-2.5) on the developed porous structure of the resulting carbons was studied for 1 h of carbonization time. Surface properties of the activated carbons were dependent on a combined effect of the conditions employed. Carbons developed either with R = 1.5 over the range 400-500 degrees C, or with R = 2 at 500 degrees C exhibited surface areas of around 1100 m2/g, the latter conditions promoting a larger pore volume and enhanced mesoporous character. For both ratios, temperature above 500 degrees C led to reduction in porosity development. A similar effect was found for the highest ratio (R = 2.5) and 500 degrees C. The influence of carrying out the carbonization either for times shorter than 1 h or under flowing N2 was also examined at selected conditions (R = 2, 500 degrees C). Shorter times induced increase in the surface area (approximately 1300 m2/g), yielding carbons with smaller mean pore radius. Activated carbons obtained under flowing N2 possessed predominant microporous structures and larger ash contents than the samples derived in the self-generated atmosphere.
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Compuestos Inorgánicos de Carbono/análisis , Ácidos Fosfóricos/química , Poaceae/química , Adsorción , Biotecnología/métodos , Carbono/química , Compuestos Inorgánicos de Carbono/química , Cinética , Microscopía Electrónica de Rastreo , Nitrógeno/química , Oxígeno , Presión , Temperatura , Factores de TiempoRESUMEN
Changes in chemical and surface characteristics of Brazil Nut shells (Bertholletia excelsa) due to pyrolysis at different temperatures (350 degrees C, 600 degrees C, 850 degrees C) were examined. For this purpose, proximate and ultimate analyses, physical adsorption measurements of N2 (-196 degrees C) and CO, (25 degrees C) as well as samples visualisation by scanning electronic microscopy (SEM) were performed. Appreciable differences in the residue characteristics, depending markedly on the pyrolysis temperature, were observed. Release of volatile matter led to the development of pores of different sizes. Progressive increases in micropore development with increasing pyrolysis temperature took place, whereas a maximum development of larger pores occurred at 600 degrees C. Furthermore, kinetics measurements of Brazil Nut shells pyrolysis from ambient temperature up to 900 degrees C were performed by non-isothermal thermogravimetric analysis. A model taking into account the significant changes in the residue during pyrolysis, through an increase in the activation energy with temperature and solid conversion, were found to properly fit the kinetics data over the wide range of degradation investigated.
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Nueces/química , Temperatura , Cinética , Microscopía Electrónica de Rastreo , Nitrógeno/química , Nueces/ultraestructuraRESUMEN
An evolutionary diagram that takes into account the development of personality and its structuring or restructuring was developed thanks to a better understanding of autistic disorders from a psychodynamic point of view through long term psychoanalytic treatment of autistic children. This grid is organised around the major stages of the formation of the bodily ego which autistic children helped us understand better. The construction of space and the capacities of cognitive instrumentation are logically within this line of structuring. These major stages are defined: the first is the "successful" autistic state; the second is the stage where the primary skin is recovered (feeling of a circular envelope); the third is the symbiotic phase which includes vertical splitting then horizontal splitting of the image of the body; finally, the fourth is the phase of individuation/separation into a whole body. At each stage the following are assessed: state of the image of the body, of the gaze, of language, of writing, the autistic symptoms, emotional-relational manifestations, exploration of space and objects, recognition in time, the aggressive behaviours, reactivity to pain and to immune states (somatic and psychosomatic manifestations).
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Trastorno Autístico/psicología , Desarrollo Infantil , Psiquiatría Infantil/métodos , Modelos Psicológicos , Terapia Psicoanalítica , Trastorno Autístico/diagnóstico , Trastorno Autístico/terapia , Imagen Corporal , Ego , Humanos , Lactante , Desarrollo del Lenguaje , Escalas de Valoración PsiquiátricaRESUMEN
The trigeminal motor root was studied in the electron microscope at different proximodistal levels in eight adult cats. Counts at a level halfway between the trigeminal ganglion and the pontine junction showed that the root contains about 9% (n = approximately 300) unmyelinated axon profiles at this level. Small groups of unmyelinated axons occur on both sides of the PNS-CNS border, in the surrounding pia mater, and in perivascular spaces of the CNS compartment. Examination of serial sections from the PNS-CNS transitional region showed that some unmyelinated axons actually cross the PNS-CNS border. The functional significance of these fibres remains unknown.
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Ganglios Espinales/ultraestructura , Nervio Trigémino/ultraestructura , Animales , Axones/ultraestructura , Gatos , Sistema Nervioso Central/ultraestructura , Microscopía Electrónica , Vaina de Mielina/ultraestructura , Nervios Periféricos/ultraestructuraRESUMEN
The occurrence of unmyelinated and small myelinated axons and of nerve fibres with a substance P-like immunoreactivity was studied in juxtamedullary L7 ventral root fascicles and surrounding pia mater of kittens and cats. Electron microscopic analysis of thin transverse serial sections from this region in adult cats showed that the number of unmyelinated axon profiles decreases rapidly as the CNS is approached, reaching zero near or at the CNS/PNS border. No unmyelinated axons were found to enter the CNS through this root. At least to some extent, the disappearance of unmyelinated ventral root axons from the juxtamedullary root fascicles was due to presence of intrafascicular axonal hairpin loops and to a shift of axons from ventral root fascicles to the pia mater. It was also found that, in the L7 ventral root, the content of unmyelinated axons in the pia mater is lower in kittens than in cats. Fluorescence microscopic examination of specimens incubated with substance P antiserum showed that some looping axons and ventral root-pia mater axons were substance P immunoreactive. These observations suggest the hypothesis that sensory unmyelinated axons might grow through the L7 ventral root and enter the pia mater during postnatal development. Moreover they show that the occurrence of sensory unmyelinated axons in ventral roots does not necessarily contradict the law of Magendie .