Novedades corológicas y taxonómicas selectas para el catálogo de la flora vascular del Norte de Marruecos

Para este artículo se han se han selecionado 65 taxones escogidos por su especial interés corológico o taxonómico, fruto de las campañas de prospección florística efectuadas en el norte de Marruecos en los años 2004 y 2005. De ellos 15 representan novedad absoluta para el Catálogo del norte de Marruecos y se confirma la presencia de otros citados bibliográficamente en solo una localidad. Euphorbia exigua subsp. merinoi se indica por vez primera para Andalucía y Chamaesyce serpens (Kunth) Small y Fumana scoparia subsp. paradoxa (Heywood) Güemes son nuevas para Marruecos. Se mencionan por vez primera para el área oriental del territorio a 31 especies. Se describe un nuevo taxón: Sideritis mezgouti Molero & J. M. Montserrat, sp. nova. Se constata de nuevo la importancia de la cuenca alta y media del río Moulouya como vía de penetración del elemento sáharo-arábigo, el más numeroso en estas aportaciones, que alcanza plenamente el extremo suroriental del territorio (Guercif y Beni-Sanssen).This paper lists 65 selected taxa specially chosen for their chorological or taxonomical interest. From these we indicate 15 for the first time for the Checklist of Northern Morocco. Many other species previously cited from one natural area alone, based only on literature references, are confirmed here. Chamaesyce serpens (Kunth) Small and Fumana scoparia subsp. paradoxa (Heywood) Güemes are indicated for the first time for the Moroccan flora and 31 species are indicated as new for the Eastern part of Northern Morocco. Euphorbia exigua subsp. merinoi is mentioned for first time for Andalucía. One new taxon is described: Sideritis mezgouti Molero & J.M. Montserrat, sp. nova. The distribution of the species mentioned here shows that many belong to the Saharo-Arabic element, which represent a remarkable progression of the Saharan floristic element into the low basin of the river Moulouya.Proyecto BIOGEO (REN 2002-04478-CO3-03/GLO)GReB (2001SGR00125

La vegetación de zonas erosionadas en la depresión media del Ebro y en el Prepirineo: influencia de factores climáticos, topográficos y geomorfológicos en la composición florística de las comunidades vegetales

[Resumen] Se han analizado 732 inventarios de vegetación en zonas sometidas a procesos erosivo-sedimentarios de un área del NE de la Península Ibérica, muy diversa climática y litológicamente (yesos, arcillas, margas y flysch). El objetivo del estudio es determinar cómo afectan dichos procesos a la composición florística de las comunidades vegetales de los diferentes sustratos. El tipo de sustrato ejerció una gran influencia sobre los procesos estudiados, siendo la cobertura de las fanerógamas el parámetro que mejor se asoció con el grado de erosión. En las zonas más secas con bajas tasas de erosión (yesos), las características topográficas controlaron la distribución de las comunidades vegetales, mientras que en las zonas más húmedas, sometidas a procesos erosivos más dinámicos (margas), la composición florística fué más homogénea y menos dependiente de la topografía y del grado de erosión. Los procesos erosivosedimentarios explicaron mejor la composición florística cuanto menor era la escala espacial de análisis.[Abstract] We have analysed 732 releves of plant communities taken from eroded lands in the NE Iberian Peninsula. This diverse area has very different climates and substrata: gypsum, clays, marls and flysch. The aim of the study was to explore how erosion and sedimentation processes affect floristic composition of plant communities in such different substrata. Substratum had a high influence on the studied processes, the cover of fanerogams being the best correlated parameter with erosion grade. In the driest lands, with low erosion rates (gypsum), plant community distribution was mostly affected by topography, but in the wettest areas, with strong and more dynamic erosional processes (marls), the floristic composition was more homogeneus and depended less on the topography and the erosion grade. The erosionsedimentation processes better explained the floristic composition when the scale of analysis was reduced

Contribucion al conocimiento de la flora del Sistema Iberico Septentrional

Se aporta un catálogo florístico de 313 táxones seleccionados procedentes de algunas de las sierras septentrionales del Sistema Ibérico aragonés: Sierras de Villarroya, Vicort, Cucalón y Retuerta, Monte de Herrera, la Modorra de Bádenas y Baños de Segura. La visita a algunas de las localidades clásicas de ASSO, ha permitido confirmar numerosas citas de las que aparecen en su Synopsis stirpium indigenarum Aragoniae (1779), así como establecer algunas sinonimias. En el aspecto nomenclatural se propone una nueva combinación: Androsace elongata L. subsp. breistrofferi (Charpin & Greuter) J . Molero & JM. Montserrat, comb. nova. En el aspecto corológico, una lista, que no pretende ser exahustiva, sobre novedades para la Flora aragonesa y otras especies escasamente citadas que incluye: Paronychia rouyana, Suene scabriflora, Sisymbrium macroloma, Hutera hispida, Saxifraga losae var. camarae, Rosa arvensis, Aphanes cornucopioides, Lathyrus cirrhosus, Trifolium retusum, Trifolium gemellum, Seseli cantabricum, Daucus durieua, Anthemis alpestris fma. ligulata , Hieracium castellanum, Festuca capillifolia , Avenula pubescens, Carex tomentosa, etc

Supercritical fluid extraction as a clean-up method for the extraction of pesticides from wool wax. A preliminary approach

Este trabajo es un estudio preliminar para el desarrollo de un metodo de extraccion de pesticidas directamente de las muestras de cera mediante extraccion con fluido supercritico. La novedad del estudio consiste en la extraccion directa de los pesticidas de la cera de lana cruda sin ninguna limpieza previa, cuando muchos autores han considerado casi imposible la extraccion directa.The work presented is a preliminary study for the development of a method for the extraction of pesticides from wax samples by means of superficial fluid extraction. The novelty of the study is the direct extraction of the pesticides from raw wool wax without any cleanup, as direct extraction has been considered almost impossible by many authors

Gypsophile chemistry unveiled: Fourier transform infrared (FTIR) spectroscopy provides new insight into plant adaptations to gypsum soils

Gypsum soils are among the most restrictive and widespread substrates for plant life. Plants living on gypsum are classified as gypsophiles (exclusive to gypsum) and gypsovags (non-exclusive to gypsum). The former have been separated into wide and narrow gypsophiles, each with a putative different ecological strategy. Mechanisms displayed by gypsum plants to compete and survive on gypsum are still not fully understood. The aim of this study was to compare the main chemical groups in the leaves of plants with different specificity to gypsum soils and to explore the ability of Fourier transform infrared (FTIR) spectra analyzed with neural network (NN) modelling to discriminate groups of gypsum plants. Leaf samples of 14 species with different specificity to gypsum soils were analysed with FTIR spectroscopy coupled to neural network (NN) modelling. Spectral data were further related to the N, C, S, P, K, Na, Ca, Mg and ash concentrations of samples. The FTIR spectra of the three groups analyzed showed distinct features that enabled their discrimination through NN models. Wide gypsophiles stood out for the strong presence of inorganic compounds in their leaves, particularly gypsum and, in some species, also calcium oxalate crystals. The spectra of gypsovags had less inorganic chemical species, while those of narrow gypsum endemisms had low inorganics but shared with wide gypsophiles the presence of oxalate. Gypsum and calcium oxalate crystals seem to be widespread amongst gypsum specialist plants, possibly as a way to tolerate excess Ca and sulphate. However, other mechanisms such as the accumulation of sulphates in organic molecules are also compatible with plant specialization to gypsum. While gypsovags seem to be stress tolerant plants that tightly regulate the uptake of S and Ca, the ability of narrow gypsum endemisms to accumulate excess Ca as oxalate may indicate their incipient specialization to gypsum

Quantum cavitation in liquid helium

Using a functional-integral approach, we have determined the temperature below which cavitation in liquid helium is driven by thermally assisted quantum tunneling. For both helium isotopes, we have obtained the crossover temperature in the whole range of allowed negative p essures. Our results are compatible with recent experimental results on 4He.Comment: Typeset using Revtex, 10 pages and 2 figures, Phys. Rev B (1996

Towards population inversion of electrically pumped Er ions sensitized by Si nanoclusters

This study reports the estimation of the inverted Er fraction in a system of Er doped silicon oxide sensitized by Si nanoclusters, made by magnetron sputtering. Electroluminescence was obtained from the sensitized erbium, with a power efficiency of 10¿2 %. By estimating the density of Er ions that are in the first excited state, we find that up to 20% of the total Er concentration is inverted in the best device, which is one order of magnitude higher than that achieved by optical pumping of similar materials

Tracking homogeneous reactions during electrodialysis of organic acids via EIS

[EN] Organic acids are highly valuable platform chemicals that can be obtained from bioresources and subsequently transformed into a wide spectrum of profitable consumer goods. After their synthesis, organic acids need to be separated from other by-products and conveniently upconcentrated. Based on the ionic nature of organic acids, electromembrane processes are viable technologies for their recovery. Transport of weak acids through ion- exchange membranes is a complex process influenced by multiple phenomena, i.e. concentration polarization, water dissociation and counterion-membrane interactions. In the present study, the transport of two different organic acids (citric and oxalic acid) through anion-exchange membranes is investigated by means of using linear sweep voltammetry, chronopotentiometry and electrochemical impedance spectroscopy (EIS). Results have shown that, at pH values where multivalent acid anions predominate in solution, a first limiting current density is registered in the current-voltage curves, followed by an increase in membrane resistance. A further increase in current leads to a second limiting current density and a steeper increase in membrane resistance associated with an intensified ion depletion. A strong correlation between polarization curves and electrochemical impedance measurements reveals that such increase in resistance is prompted by generation of Hþ and OH? ions and the concomitant onset of homogeneous reactions in very thin solution layers. The generation of Hþ and OH? ions is tracked by a Gerischer arc in the impedance spectra. As the polarization level increases, the subsequent reaction of multivalent anions into lower-charge acid anions involves the evolution of additional Gerischer arcs. Furthermore, the lower conductivity of the reaction products correlates with the increased system resistance. The characteristic times of these reactions are in the order of milliseconds, thus being only directly accessible with the use of frequency response analysis techniques, such as EIS.M.C. Marti-Calatayud acknowledges the support of Generalitat Valenciana through the funding APOSTD/2017/059.Martí Calatayud, MC.; Evdochenko, E.; Bär, J.; García Gabaldón, M.; Wessling, M.; Pérez-Herranz, V. (2020). Tracking homogeneous reactions during electrodialysis of organic acids via EIS. Journal of Membrane Science. 595:1-10. https://doi.org/10.1016/j.memsci.2019.117592S110595Kiss, A. A., Lange, J.-P., Schuur, B., Brilman, D. W. F., van der Ham, A. G. J., & Kersten, S. R. A. (2016). Separation technology–Making a difference in biorefineries. Biomass and Bioenergy, 95, 296-309. doi:10.1016/j.biombioe.2016.05.021Abels, C., Carstensen, F., & Wessling, M. (2013). Membrane processes in biorefinery applications. Journal of Membrane Science, 444, 285-317. doi:10.1016/j.memsci.2013.05.030Sun, Z., Fridrich, B., de Santi, A., Elangovan, S., & Barta, K. (2018). Bright Side of Lignin Depolymerization: Toward New Platform Chemicals. Chemical Reviews, 118(2), 614-678. doi:10.1021/acs.chemrev.7b00588Wang, M., Ma, J., Liu, H., Luo, N., Zhao, Z., & Wang, F. (2018). Sustainable Productions of Organic Acids and Their Derivatives from Biomass via Selective Oxidative Cleavage of C–C Bond. ACS Catalysis, 8(3), 2129-2165. doi:10.1021/acscatal.7b03790Koutinas, A. A., Vlysidis, A., Pleissner, D., Kopsahelis, N., Lopez Garcia, I., Kookos, I. K., … Lin, C. S. K. (2014). Valorization of industrial waste and by-product streams via fermentation for the production of chemicals and biopolymers. Chemical Society Reviews, 43(8), 2587. doi:10.1039/c3cs60293aBetiku, E., Emeko, H. A., & Solomon, B. O. (2016). Fermentation parameter optimization of microbial oxalic acid production from cashew apple juice. Heliyon, 2(2), e00082. doi:10.1016/j.heliyon.2016.e00082Regestein, L., Klement, T., Grande, P., Kreyenschulte, D., Heyman, B., Maßmann, T., … Büchs, J. (2018). From beech wood to itaconic acid: case study on biorefinery process integration. Biotechnology for Biofuels, 11(1). doi:10.1186/s13068-018-1273-yDi Marino, D., Jestel, T., Marks, C., Viell, J., Blindert, M., Kriescher, S. M. A., … Wessling, M. (2019). Carboxylic Acids Production via Electrochemical Depolymerization of Lignin. ChemElectroChem, 6(5), 1434-1442. doi:10.1002/celc.201801676López-Garzón, C. S., & Straathof, A. J. J. (2014). Recovery of carboxylic acids produced by fermentation. Biotechnology Advances, 32(5), 873-904. doi:10.1016/j.biotechadv.2014.04.002Handojo, L., Wardani, A. K., Regina, D., Bella, C., Kresnowati, M. T. A. P., & Wenten, I. G. (2019). Electro-membrane processes for organic acid recovery. RSC Advances, 9(14), 7854-7869. doi:10.1039/c8ra09227cStodollick, J., Femmer, R., Gloede, M., Melin, T., & Wessling, M. (2014). Electrodialysis of itaconic acid: A short-cut model quantifying the electrical resistance in the overlimiting current density region. Journal of Membrane Science, 453, 275-281. doi:10.1016/j.memsci.2013.11.008Brauns, E. (2008). Towards a worldwide sustainable and simultaneous large-scale production of renewable energy and potable water through salinity gradient power by combining reversed electrodialysis and solar power? Desalination, 219(1-3), 312-323. doi:10.1016/j.desal.2007.04.056Abu Khalla, S., & Suss, M. E. (2019). Desalination via chemical energy: An electrodialysis cell driven by spontaneous electrode reactions. Desalination, 467, 257-262. doi:10.1016/j.desal.2019.04.031Chandra, A., Tadimeti, J. G. D., & Chattopadhyay, S. (2018). Transport hindrances with electrodialytic recovery of citric acid from solution of strong electrolytes. Chinese Journal of Chemical Engineering, 26(2), 278-292. doi:10.1016/j.cjche.2017.05.010Andersen, S. J., Hennebel, T., Gildemyn, S., Coma, M., Desloover, J., Berton, J., … Rabaey, K. (2014). Electrolytic Membrane Extraction Enables Production of Fine Chemicals from Biorefinery Sidestreams. Environmental Science & Technology, 48(12), 7135-7142. doi:10.1021/es500483wChai, P., Wang, J., & Lu, H. (2015). The cleaner production of monosodium l -glutamate by resin-filled electro-membrane reactor. Journal of Membrane Science, 493, 549-556. doi:10.1016/j.memsci.2015.07.023Fu, L., Gao, X., Yang, Y., Aiyong, F., Hao, H., & Gao, C. (2014). Preparation of succinic acid using bipolar membrane electrodialysis. Separation and Purification Technology, 127, 212-218. doi:10.1016/j.seppur.2014.02.028Kumar, M., Tripathi, B. P., & Shahi, V. K. (2009). Electro-membrane reactor for separation and in situ ion substitution of glutamic acid from its sodium salt. Electrochimica Acta, 54(21), 4880-4887. doi:10.1016/j.electacta.2009.04.036Pismenskaya, N., Nikonenko, V., Auclair, B., & Pourcelly, G. (2001). Transport of weak-electrolyte anions through anion exchange membranes. Journal of Membrane Science, 189(1), 129-140. doi:10.1016/s0376-7388(01)00405-7Martí-Calatayud, M. C., Buzzi, D. C., García-Gabaldón, M., Ortega, E., Bernardes, A. M., Tenório, J. A. S., & Pérez-Herranz, V. (2014). Sulfuric acid recovery from acid mine drainage by means of electrodialysis. Desalination, 343, 120-127. doi:10.1016/j.desal.2013.11.031Martí-Calatayud, M. C., Buzzi, D. C., García-Gabaldón, M., Bernardes, A. M., Tenório, J. A. S., & Pérez-Herranz, V. (2014). Ion transport through homogeneous and heterogeneous ion-exchange membranes in single salt and multicomponent electrolyte solutions. Journal of Membrane Science, 466, 45-57. doi:10.1016/j.memsci.2014.04.033Belashova, E. D., Pismenskaya, N. D., Nikonenko, V. V., Sistat, P., & Pourcelly, G. (2017). Current-voltage characteristic of anion-exchange membrane in monosodium phosphate solution. Modelling and experiment. Journal of Membrane Science, 542, 177-185. doi:10.1016/j.memsci.2017.08.002Martí-Calatayud, M., García-Gabaldón, M., & Pérez-Herranz, V. (2018). Mass Transfer Phenomena during Electrodialysis of Multivalent Ions: Chemical Equilibria and Overlimiting Currents. Applied Sciences, 8(9), 1566. doi:10.3390/app8091566Melnikova, E. D., Pismenskaya, N. D., Bazinet, L., Mikhaylin, S., & Nikonenko, V. V. (2018). Effect of ampholyte nature on current-voltage characteristic of anion-exchange membrane. Electrochimica Acta, 285, 185-191. doi:10.1016/j.electacta.2018.07.186Femmer, R., Mani, A., & Wessling, M. (2015). Ion transport through electrolyte/polyelectrolyte multi-layers. Scientific Reports, 5(1). doi:10.1038/srep11583Belloň, T., Polezhaev, P., Vobecká, L., Svoboda, M., & Slouka, Z. (2019). Experimental observation of phenomena developing on ion-exchange systems during current-voltage curve measurement. Journal of Membrane Science, 572, 607-618. doi:10.1016/j.memsci.2018.11.037Rybalkina, O. A., Tsygurina, K. A., Melnikova, E. D., Pourcelly, G., Nikonenko, V. V., & Pismenskaya, N. D. (2019). Catalytic effect of ammonia-containing species on water splitting during electrodialysis with ion-exchange membranes. Electrochimica Acta, 299, 946-962. doi:10.1016/j.electacta.2019.01.068Tanaka, Y. (2010). Water dissociation reaction generated in an ion exchange membrane. Journal of Membrane Science, 350(1-2), 347-360. doi:10.1016/j.memsci.2010.01.010Belova, E. I., Lopatkova, G. Y., Pismenskaya, N. D., Nikonenko, V. V., Larchet, C., & Pourcelly, G. (2006). Effect of Anion-exchange Membrane Surface Properties on Mechanisms of Overlimiting Mass Transfer. The Journal of Physical Chemistry B, 110(27), 13458-13469. doi:10.1021/jp062433fBelova, E., Lopatkova, G., Pismenskaya, N., Nikonenko, V., & Larchet, C. (2006). Role of water splitting in development of electroconvection in ion-exchange membrane systems. Desalination, 199(1-3), 59-61. doi:10.1016/j.desal.2006.03.142Zabolotskiy, V. I., But, A. Y., Vasil’eva, V. I., Akberova, E. M., & Melnikov, S. S. (2017). Ion transport and electrochemical stability of strongly basic anion-exchange membranes under high current electrodialysis conditions. Journal of Membrane Science, 526, 60-72. doi:10.1016/j.memsci.2016.12.028Papagianni, M. (2007). Advances in citric acid fermentation by Aspergillus niger: Biochemical aspects, membrane transport and modeling. Biotechnology Advances, 25(3), 244-263. doi:10.1016/j.biotechadv.2007.01.002Komáromy, P., Bakonyi, P., Kucska, A., Tóth, G., Gubicza, L., Bélafi-Bakó, K., & Nemestóthy, N. (2019). Optimized pH and Its Control Strategy Lead to Enhanced Itaconic Acid Fermentation by Aspergillus terreus on Glucose Substrate. Fermentation, 5(2), 31. doi:10.3390/fermentation5020031Martí-Calatayud, M. C., García-Gabaldón, M., & Pérez-Herranz, V. (2012). Study of the effects of the applied current regime and the concentration of chromic acid on the transport of Ni2+ ions through Nafion 117 membranes. Journal of Membrane Science, 392-393, 137-149. doi:10.1016/j.memsci.2011.12.012Martí-Calatayud, M. C., García-Gabaldón, M., & Pérez-Herranz, V. (2013). Effect of the equilibria of multivalent metal sulfates on the transport through cation-exchange membranes at different current regimes. Journal of Membrane Science, 443, 181-192. doi:10.1016/j.memsci.2013.04.058Butylskii, D. Y., Mareev, S. A., Pismenskaya, N. D., Apel, P. Y., Polezhaeva, O. A., & Nikonenko, V. V. (2018). Phenomenon of two transition times in chronopotentiometry of electrically inhomogeneous ion exchange membranes. Electrochimica Acta, 273, 289-299. doi:10.1016/j.electacta.2018.04.026Moya, A. A. (2016). Electrochemical Impedance of Ion-Exchange Membranes with Interfacial Charge Transfer Resistances. The Journal of Physical Chemistry C, 120(12), 6543-6552. doi:10.1021/acs.jpcc.5b12087Femmer, R., Martí-Calatayud, M. C., & Wessling, M. (2016). Mechanistic modeling of the dielectric impedance of layered membrane architectures. Journal of Membrane Science, 520, 29-36. doi:10.1016/j.memsci.2016.07.055Roghmans, F., Martí-Calatayud, M. C., Abdu, S., Femmer, R., Tiwari, R., Walther, A., & Wessling, M. (2016). Electrochemical impedance spectroscopy fingerprints the ion selectivity of microgel functionalized ion-exchange membranes. Electrochemistry Communications, 72, 113-117. doi:10.1016/j.elecom.2016.09.009Kniaginicheva, E., Pismenskaya, N., Melnikov, S., Belashova, E., Sistat, P., Cretin, M., & Nikonenko, V. (2015). Water splitting at an anion-exchange membrane as studied by impedance spectroscopy. Journal of Membrane Science, 496, 78-83. doi:10.1016/j.memsci.2015.07.050Pismenskaya, N. D., Pokhidnia, E. V., Pourcelly, G., & Nikonenko, V. V. (2018). Can the electrochemical performance of heterogeneous ion-exchange membranes be better than that of homogeneous membranes? Journal of Membrane Science, 566, 54-68. doi:10.1016/j.memsci.2018.08.055Harding, M. S., Tribollet, B., Vivier, V., & Orazem, M. E. (2017). The Influence of Homogeneous Reactions on the Impedance Response of a Rotating Disk Electrode. Journal of The Electrochemical Society, 164(11), E3418-E3428. doi:10.1149/2.0411711jesNikonenko, V., Lebedev, K., Manzanares, J. A., & Pourcelly, G. (2003). Modelling the transport of carbonic acid anions through anion-exchange membranes. Electrochimica Acta, 48(24), 3639-3650. doi:10.1016/s0013-4686(03)00485-

Quantifying 210Po/210Pb disequilibrium in seawater: A comparison of two precipitation methods with differing results

The disequilibrium between lead-210 (210Pb) and polonium-210 (210Po) is increasingly used in oceanography to quantify particulate organic carbon (POC) export from the upper ocean. This proxy is based on the deficits of 210Po typically observed in the upper water column due to the preferential removal of 210Po relative to 210Pb by sinking particles. Yet, a number of studies have reported unexpected large 210Po deficits in the deep ocean indicating scavenging of 210Po despite its radioactive mean life of ∼ 200 days. Two precipitation methods, Fe(OH)3 and Co-APDC, are typically used to concentrate Pb and Po from seawater samples, and deep 210Po deficits raise the question whether this feature is biogeochemically consistent or there is a methodological issue. Here, we present a compilation of 210Pb and 210Po studies that suggests that 210Po deficits at depths \u3e 300 m are more often observed in studies where Fe(OH)3 is used to precipitate Pb and Po from seawater, than in those using Co-APDC (in 68 versus 33% of the profiles analyzed for each method, respectively). In order to test whether 210Po/210Pb disequilibrium can be partly related to a methodological artifact, we directly compared the total activities of 210Pb and 210Po in four duplicate ocean depth-profiles determined by using Fe(OH)3 and Co-APDC on unfiltered seawater samples. While both methods produced the same 210Pb activities, results from the Co-APDC method showed equilibrium between 210Pb and 210Po below 100 m, whereas the Fe(OH)3 method resulted in activities of 210Po significantly lower than 210Pb throughout the entire water column. These results show that 210Po deficits in deep waters, but also in the upper ocean, may be greater when calculated using a commonly used Fe(OH)3 protocol. This finding has potential implications for the use of the 210Po/210Pb pair as a tracer of particle export in the oceans because 210Po (and thus POC) fluxes calculated using Fe(OH)3 on unfiltered seawater samples may be overestimated. Recommendations for future research are provided based on the possible reasons for the discrepancy in 210Po activities between both analytical methods