A discretization method for the characterization of a plate heat exchanger working as evaporator during transient conditions

In this work, a method for the characterization of a plate heat exchanger working as evaporator is presented. It is based on a one-dimensional discretization of the exchanger, which solves the heat transfer balance equations by means of an iterative methodology based on a heat transfer area converging method. The inputs of the method are the flow rates of the fluids, the inlet enthalpy of the refrigerant, the superheating, and the inlet temperature and pressure of the secondary fluid. Once the inlet pressure of the refrigerant is assumed, pressure drop is calculated in each cell and then enthalpy. The consideration of the proper heat transfer coefficient (HTC) correlations allows the calculation of the heat transfer area, which is after compared to the actual one. The method has been validated by means of a database of 366 experimental data obtained for eight plate heat exchangers working as evaporators by using six different refrigerants, namely R134a, R1234yf, R513A, R744, R290, and R507A. As the method requires suitable correlations for the calculation of the HTC and pressure drop, several correlations for the HTC and Δp found in the literature are studied and the results obtained by using them are presented in terms of the maximum absolute relative deviation (MARD). The results corresponding to the correlation which yields the best results are graphically represented. Finally, the method is used to predict the evaporator performance operating in transient conditions. The results obtained show an excellent agreement with the experimental results collected during the transient operation of a transcritical CO2 water heater coupled to a storage tank.The work in this paper has been financed by the Spanish Ministry of Science and Innovation under Project TED2021-131173B–I00 and the NextGenerationEU recovery plan

Correction of negative dysphotopsia in Crystalens “Z syndrome”

We report a case of negative dysphotopsia in the left eye of a 56-year-old patient three months after uneventful bilateral phacoemulsification and implantation of a Crystalens® intraocular lens (Bausch and Lomb®) placed in the capsular bag. Three months postoperatively, the patient described visual field loss in the inferior temporal quadrant in the left eye under low light conditions. Anterior capsulorhexis was eccentric, allowing the inferior temporal optic edge to move forward, producing late asymmetric vault of the lens. One month later, when the equatorial diameter of the capsular bag decreased, we pushed the inferior temporary hinge backwards so that the lens moved back into the correct position. Six months after relocation, the lens position remained stable and negative dysphotopsia was absent. This case shows Crystalens Z syndrome as a new etiology of negative dysphotopsia, and a successful novel treatment in a patient without capsular fibrosis

Drought differently destabilizes soil structure in a chronosequence of abandoned agricultural lands

Climate change is causing an increase in the frequency and severity of drought, and this has a significant influence on the global C cycle as soils are the main sink for C in terrestrial ecosystems. Drought can have serious consequences for the structural stability of the soil, which influences the protection of the organic matter stored in the soils and hence its mineralization. In this work we study the effects of an extreme drought event on the structural stability of the soil in Mediterranean annual grasslands developed after the abandonment of agricultural activity. This was done by building a chronosequence of abandoned vineyards and determining the changes in the stability of the soil aggregates and organic matter by monitoring these parameters for three consecutive years in permanent plots with different ages of abandonment. This period of time included an extreme drought event in the second year with a strong positive thermal anomaly, which caused a serious structural destabilization of the soil and had a major impact on the soil C and N cycles. The breakdown of the soil aggregates left unprotected a large amount of organic substrates that were rapidly mineralized when the environmental conditions were favourable for soil biological activity. This had significant repercussions on the functioning of these abandoned ecosystems, which became sources of atmospheric CO2, when under normal conditions they act as C sinks. Furthermore, the effects of this extreme event were more severe in the plots with longer periods of abandonment, which have the highest amount of C accumulated in the soil

THYMUS X FAUSTINOI, HÍBRIDO NUEVO DEL SURESTE DE LA PENÍNSULA IBÉRICA

A new hybrid Thymus x faustinoi, from the Murcia region, growing with populations of Th. mastichina subsp. mastichina and Th. Granatensis subsp. Micranthus and intermediate morphogicaly between the both taxa, is described. A list of the new hybrids described in the last nine years for the Iberian Peninsula is included.Se describe el nuevo híbrido Thymus x faustinoi, encontrado en la Región de Murcia entre poblaciones de Th. mastichina subsp. Mastichina y Th. granatensis subsp. Micranthus e intermedio morfológicamente entre ambos taxones. Además se listan los híbridos nuevos descritos de este género para la Península Ibérica en los últimos 9 años

Mediterranean grassland succession as an indicator of changes in ecosystem biodiversity and functionality

The abandonment of agricultural lands triggers a secondary succession of plant species which implies important changes in soil quality. Annual Mediterranean grasslands are known to be persistent on abandoned agriculture lands in the western Mediterranean. We used plant taxonomic and functional approaches to determine the role of Mediterranean grasslands as an indicator of changes in ecosystem biodiversity and functionality. We tested the hypothesis that Mediterranean grasslands are a suitable model for monitoring biodiversity and soil fertility in a secondary succession. Soil and vegetation features on 21 permanent plots were monitored in 2016 and 2020. Numerical classifications based on floristic composition showed two different plant communities independently of the sampling year: early-stage grasslands in the first post-abandonment decade and late-stage grasslands after the first post-abandonment decade. Generalized linear model and redundancy analysis also revealed differences in growth forms, functional traits and soil functionality between communities. Late-stage grasslands was characterized by enriched bryophyte coverage and an impoverishment in hemicryptophytes and plant latex segregators growing on soils with a higher hydrolase enzyme activity and TOC content compared to early-stage grassland. Our results suggest that annual Mediterranean grasslands growing on siliceous soils denoting a mature-stage succession, and floristically characterized by the symbiont plant with Ascomycota, Tuberaria guttata, and a high bryophyte cover, are worthy of recognition for conservation

Identifying populations of wild vines and grapevines trained on the facades of old farmhouses.

El presente trabajo se ha centrado sobre la Cuadrilla de Ayala (Álava), donde se han localizado ocho poblaciones relictas de vid silvestre en diversos hábitats. Se ha comprobado su carácter dioico durante el periodo de floración. Se han identificado las principales especies parásitas existentes sobre estas parras y las principales componentes de su vegetación acompañante. Por otro lado, se han estudiado quince vides cultivadas, con una edad superior a cincuenta años, situadas en la fachada principal de los caseríos. El análisis del ADN de ambos tipos de parras se ha realizado con 48 marcadores SNPs. Los resultados obtenidos han sido comparados con la base de datos disponible en el Instituto de Ciencias de la Vid y del Vino (Logroño), a fin de proceder a la caracterización genética de las muestras.This paper focuses on the Cuadrilla de Ayala (Álava province, Spain), where eight relic wild grapevine populations were located in different habitats. The dioecious nature of these lianas was determined at flowering time. The main parasitic species on these vines and also the most frequent taxa of their accompanying vegetation were identified. On the other hand, fifteen vines, aged in excess of fifty, and located in the main entrances of traditional farmhouses (caseríos), were also studied. The analysis of the DNA from both kinds of sampled vines was based on 48 SNPs markers. Results were compared with the available data base at the Instituto de Ciencias de la Vid y del Vino (Logroño, Spain) for the sample genetic characterization

Suelos del entorno del balneario

Soil characteristics are decisive in groundwater quality. The impact of human activities, especially in areas subject to agricultural pressure, involves potential risks which may be critical to the viability of the water resource. This work gathers together the study of three representative soils located in the thermal environment of “Villa Olmedo”, Valladolid. All of them have developed from arkoses and found around 750 m elevation in a zone of flat topography. Morphological, physical, chemical and mineralogical properties of these soils were analyzed. They are poorly developed, coarse textured, with pH close to neutrality and antric features in the surface horizons. El conocimiento del suelo es imprescindible para comprender el riesgo de la posible afectación de las aguas subterráneas, especialmente en áreas sometidas a una fuerte presión de actividad agrícola. Se presenta el estudio de tres suelos localizados en los alrededores del Balneario “Villa de Olmedo”, provincia de Valladolid. Se han desarrollado a partir de arcosas, situados en topografía llana, con una altitud entorno a los 750 m y bajo clima Mediterráneo templado. Se analizaron las propiedades morfológicas, físicas, químicas y mineralógicas de los suelos. En general, son suelos poco evolucionados, con textura gruesa, pH próximos a la neutralidad y horizontes superficiales con características ántricas.

Estudio de los suelos de los alrededores del Balneario de Villavieja de Nules (Castellón de la Plana)

Soil is the first natural barrier that has to be crossed by the compounds deposited on the Earth's surface to reach aquifers. Knowing about the physicochemical properties involved in the infiltration processes, as well as the soil type, are essential parameters which allows us to analyze the risk of contamination affecting the composition of groundwater. In this work, the environmental factors of the area around the Balneario de Villavieja Nules (Castellón de la Plana) are described, and some of the chemical, physical, and mineralogical characteristics of four soils are analyzed. Most particularly C, N, pH, CE, CIC y CO3 2‐, as well as texture, bulk density, particle density, porosity, hydraulic parameters and clay fraction mineralogy were determined. The results showed that the environmental characteristics of the area, together with the types of soil analyzed slow down the water flow processes.El  suelo  es  la  primera  barrera  natural  que  han  de  atravesar  los  compuestos  depositados  en  la  superficie  terrestre  para  llegar  a  los  acuíferos.  Conocer  las  propiedades  fisicoquímicas  que  intervienen  en  los  procesos  de  infiltración,  así  como  saber  el  tipo  de  suelo,  son  parámetros  esenciales  que  nos  permite  analizar  el  riesgo  de  contaminación  que  afecta  la  composición  del  agua  subterránea.  En  este  trabajo  se  describen  los factores ambientales de la zona, y se analizan  algunas  de  las  propiedades  químicas,  físicas  y  mineralógicas  de  cuatro  suelos  característicos  de los alrededores del Balneario de Villavieja de  Nules  (Castellón  de  la  Plana).  Para  ello  se  ha  obtenido el contenido en: C, N, pH, CE, CIC y CO3  2‐,  así  como  se  ha  determinado:  textura,  densidad  aparente,  densidad  real,  porosidad,  parámetros  hidráulicos  y  la  mineralogía  de  la  fracción  arcilla.  De  los  resultados  se  desprende  que  las  características  ambientales  de  la  zona,  junto  a  los  tipos  de  suelos  analizados  ralentizan  los procesos de flujos descendentes

Revista de Vertebrados de la Estación Biológica de Doñana

Captura de Petromyzon marinus lo en las Marismas del GuadalquivirEstudio sobre la Lagartiia de Valverde Algyroides marchi (Reptilia, Lacertidae)Dimorfismo sexual en Psammodromuus algirus (Reptilia, Lacertidae)Mecanismos de parasitización por Clamator glandarius y defensa por Pica pica.Nidificación de Cyanopica cyana en Doñana.Reproducción de la Urraca (P.pica) en DoñanaNesting relationship between Columba palambus and Milvus migransBiometría y dimorfismo sexual en el Calamón (Polphyrio porphyrio).Sobre sexo, mecanismos y proceso de reproducciónen el Buitre Leonado (Gyps fulvus)Aves anilladas por la Estación Biológica de Doñana. Informe Nº 1. (Años 1964 a 1971)Dimorfismo sexual y diferenciación de edades en Sturnus unicolor Temm.Contribución al estudio de la biología y ecología del Lirón Careto, Eliomys quercinus Linnaeus 1766, en Iberia Central, Parte 1: Crecimiento, Reproducción y Nidificación.Sobre el Lobo (Canis lupus) ibérico:1. Dimorfismo sexual en cráneosMorfología y dimorfismo sexual de la pelvis de Pitymys duodecimcostatusAlgunos aspectos del diformismo sexual en el cráneo de las Ginetas españolas, (Genetta genetta) (L.) 1758Peer reviewe