Search results for "circular"
showing 10 items of 856 documents
Architectural technologies for life environment: Spent coffee ground reuse in lime-based mortars. A preliminary assessment for innovative green therm…
2022
Spent coffee ground, the residue obtained from the brewing process, is the primary unavoidable (inedible) waste from the coffee consumption. As coffee production and beverage consumption are increasing worldwide, a more sustainable waste management is required since the usual disposal in landfill is a liability to both humans and the environment. This paper is aimed at showing a possible alternative reuse of coffee ground wastes in novel green building materials intended for thermo-plastering applications in construction, in a circular economy context. Coffee waste was used in various percentages (up to 17.5%) to assess the engineering performance of the produced bio-composite mortars. The …
Efficient Design of Waveguide Manifold Multiplexers Based on Low-Order EM Distributed Models
2015
In this paper, a new systematic technique to design manifold-coupled multiplexers in waveguide technology is proposed. The new technique uses generalized low-order electromagnetic (EM) distributed models, which constitute a half-way point between the fast, but imprecise, analytical models, and the more accurate, but costly, full-wave EM models. The method can be applied to contiguous and noncontiguous channel multiplexers, in both E-plane or H-plane configurations. This paper covers the complete design procedure for manifold multiplexers, starting from the required specifications and finishing with the physical dimensions. After explaining the general design technique for multiplexers with …
Interaction of the Alternating Double Stranded Copolymer poly(dA-dT)·poly(dA-dT) with NiCl2and CdCl22: Solution Behavior
2007
The thermal denaturation of the synthetic high molecular weight double stranded polynucleotide poly(dA-dT) x poly(dA-dT) has been studied in aqueous buffered solution (Tris 1.0 mM; pH 7.8+/-0.2) in the presence of increasing concentrations of either Ni(2+) (borderline cation) or Cd(2+) (soft cation) at four different constant ionic strength values (NaCl), making use of UV and circular dichroism (CD) spectroscopies. The experimental results show that the B-type double helix of the polymer is stabilized against thermal denaturation in the presence of both cations at low concentrations, relative to the systems where only NaCl is present, in the same conditions of ionic strength and pH. The eff…
Antileukemic ancistrobenomine B and related 5,1′-coupled naphthylisoquinoline alkaloids from the Chinese liana Ancistrocladus tectorius
2017
A striking feature of the metabolite pattern of the Southeast Asian liana Ancistrocladus tectorius (Ancistrocladaceae) is the predominance of 5,1′-coupled naphthylisoquinoline alkaloids. About 20 alkaloids of this coupling type have so far been discovered in this plant species. Here, we report on the isolation of four new 5,1′-linked naphthylisoquinolines from the twigs and stems of A. tectorius. Two of them, the ancistrobenomines B (5) and C (6), belong to the very rare group of alkaloids with a fully dehydrogenated isoquinoline portion. Likewise unusual for naphthylisoquinoline alkaloids is the presence of a hydroxymethylene group at C-3. Within the large class of meanwhile ca. 180 such n…
Resolution and Determination of the Absolute Configuration of a Twisted Bis-Lactam Analogue of Tröger's Base: A Comparative Spectroscopic and Computa…
2015
The first reported twisted bis-lactam, a racemic Tröger's base (TB) analogue (2), was resolved into its enantiomers on a chiral stationary phase HPLC column. The absolute configuration of (+)-2 was determined to be (R,R)-2 by comparing experimental and calculated vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) spectra. The absolute configuration of (-)-2 was determined by comparing experimental and calculated electronic circular dichroism (ECD) spectra. The corresponding theoretical spectra were calculated using the lowest energy conformation of (R,R)-2 and (S,S)-2 at the B3LYP/6-31G(d,p) level of theory. The absolute configuration of (+)-2 was also determined t…
A free plate model can predict guided modes propagating in tubular bone-mimicking phantoms
2014
The goal of this work was to show that a non-absorbing free plate model can predict with a reasonable accuracy guided modes measured in bone-mimicking phantoms that have circular cross-section. Experiments were carried out on uncoated and coated phantoms using a clinical axial transmission setup. Adjustment of the plate model to the experimental data yielded estimates for the waveguide characteristics (thickness, bulk wave velocities). Fair agreement was achieved over a frequency range of 0.4 to 1.6 MHz. A lower accuracy observed for the thinnest bone-mimicking phantoms was caused by limitations in the wave number measurements rather than by the model itself.
Compostaje y vermicompostaje de residuos agrícolas. Su papel en la eliminación de fármacos en el sistema suelo-planta y sobre el desarrollo vegetal
2020
La investigación dirigida hacia la gestión, tratamiento y aprovechamiento de los residuos agroindustriales para la producción de productos útiles como insumos de otros procesos industriales, ha sido y está siendo uno de los temas prioritarios en los campos de la biotecnología, agroquímica y ciencias medioambientales. Por otro lado, las normativas europeas, nacionales y autonómicas, incorporan capítulos específicos sobre los residuos derivados de la actividad agrícola y ganadera dado que su tratamiento requiere especificidades propias, debido a sus posibles orientaciones estratégicas. La detección de contaminantes emergentes en todos los compartimentos ambientales, así como en …
Nuevas herramientas para promover la reutilización del agua regenerada: Un enfoque basado en la Economía Circular y el Pago por los Servicios Ambient…
2022
Las Estaciones Depuradoras de Aguas Residuales (EDARs) son una infraestructura necesaria dentro del ciclo del agua y de la gestión de los recursos hídricos, asegurando la correcta gestión de las aguas residuales, así como su vuelta al ecosistema. Comúnmente se ha considerado a la EDAR como el “punto final” del agua residual, donde el agua depurada se descarga en las masas de agua receptoras. Sin embargo, la posibilidad de utilizar ese caudal como fuente de agua en zonas con desequilibrios hídricos se convierte en una opción cada vez más defendida. La reutilización es una solución efectiva ante los desequilibrios hídricos, permitiendo que la EDAR sea considerada como fuente de agua no conven…
Re-cyclical Urbanism. Visions, Paradigms and Projects for the Circular Metamorphosis
2017
The European Commission has clearly stated that more intelligent, sustainable and competitive development requires a paradigm shift in which the territory is construed as a primary resource, considered the holder of “development cells”, which are too often underused or mystified with regard to their real potential for use (EC, Directorate-General for Research and Innovation, 2012). Cities designed and built on land rent — on which Italy set a benchmark — need to be replaced with cities of social and cultural profitability, value creation and jobs production. Cities that recycle already-used land to avoid energy waste, smarter cities — not just technologically, but also wiser and more sentie…
Identifying and validating the presence of guanine-quadruplexes (G4) within the blood fluke parasite schistosoma mansoni
2021
Schistosomiasis is a neglected tropical disease that currently affects over 250 million individuals worldwide. In the absence of an immunoprophylactic vaccine and the recognition that mono-chemotherapeutic control of schistosomiasis by praziquantel has limitations, new strategies for managing disease burden are urgently needed. A better understanding of schistosome biology could identify previously undocumented areas suitable for the development of novel interventions. Here, for the first time, we detail the presence of G-quadruplexes (G4) and putative quadruplex forming sequences (PQS) within the Schistosoma mansoni genome. We find that G4 are present in both intragenic and intergenic regi…