Accretion and photodesorption of CO ice as a function of the incident angle of deposition

Non-thermal desorption of inter- and circum-stellar ice mantles on dust grains, in particular ultraviolet photon-induced desorption, has gained importance in recent years. These processes may account for the observed gas phase abundances of molecules like CO toward cold interstellar clouds. Ice mantle growth results from gas molecules impinging on the dust from all directions and incidence angles. Nevertheless, the effect of the incident angle for deposition on ice photo-desorption rate has not been studied. This work explores the impact on the accretion and photodesorption rates of the incidence angle of CO gas molecules with the cold surface during deposition of a CO ice layer. Infrared spectroscopy monitored CO ice upon deposition at different angles, ultraviolet-irradiation, and subsequent warm-up. Vacuum-ultraviolet spectroscopy and a Ni-mesh measured the emission of the ultraviolet lamp. Molecules ejected from the ice to the gas during irradiation or warm-up were characterized by a quadrupole mass spectrometer. The photodesorption rate of CO ice deposited at 11 K and different incident angles was rather stable between 0 and 45$^{\circ}$. A maximum in the CO photodesorption rate appeared around 70$^{\circ}$-incidence deposition angle. The same deposition angle leads to the maximum surface area of water ice. Although this study of the surface area could not be performed for CO ice, the similar angle dependence in the photodesorption and the ice surface area suggests that they are closely related. Further evidence for a dependence of CO ice morphology on deposition angle is provided by thermal desorption of CO ice experiments

EFECTO DE BIOFERTILIZANTES MICROBIANOS EN EL CRECIMIENTO DE Brachiaria brizantha (Trin) Griseb

The objective was to determine the effect of Azospirillum sp. microorganisms (biofertilizers), and arbuscular mycorrhizae (Glomus sp.) on the growth of Brachiaria brizantha. The study was performed in a completely random design with 2x6x2 factorial arrangement (two cultivars, six methods of fertilization, and two forms of water supply), evaluating the percentage and index of germination speed, height, dry matter yield, root:aerial part rate. With regard to the “A” factor, the mulato II cultivar produced 6.19 t ha-1 DM 44 days after sowing (DAS). The “B” factor presented high yields in plants with chemical fertilizer and mycorrhizae combination with Azospirillum, showing up to 50.83 % of germination, 4.07 plants at 44 das, and higher leaf production yield with combined strains of mycorrhizae with Azospirillum. The “C” factor affected the yield of the plants with water stress. The combined fertilization mycorrhizae-Azospirillum increased the yield of fodders.El objetivo fue determinar el efecto de los microrganismos (biofertilizante) Azospirillum sp., y una micorriza arbuscular  Glomus fasiculatum y Glomus cubense) sobre el crecimiento de Brachiaria brizantha. El estudio se realizó en diseño completamente al azar con arreglo factorial 2x6x2 (dos cultivares, seis métodos de fertilización y dos formas de suministro de agua), evaluando porcentaje e índice de velocidad de germinación, altura, rendimiento de materia seca, relación raíz: parte aérea. Respecto al factor “A” el cultivar mulato II produjo 6.19 t ha-1 MS a los 44 después de la siembra (DDS). El factor “B” presento rendimientos altos en plantas con fertilizante químico y combinación de micorriza con Azospirillum registrando hasta 50.83 % de germinación, 4.07 plantas a los 44 dds, mayor rendimiento en producción de hoja con cepas combinadas de micorriza con Azospirillum. El factor “C” afectó el rendimiento de las plantas con estrés hídrico. La fertilización combinada micorriza-Azospirillum aumentó el rendimiento de los forrajes

Discurso que en la solemne apertura de la Caja de ahorros=Monte de Piedad de la ciudad de Valladolid, verificada en 26 de diciembre de 1841 leyó el Ilmo. Señor Don Manuel Joaquín Tarancón presidente de la junta general directiva del mismo establecimiento

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

Science Star over Asia

The founding director of Singapore's Institute of Molecular and Cell Biology illustrates the rise of science in Asia

Testimonio de las Actas de Córtes de 1789 sobre la sucesion en la Corona de España, y de los dictámenes dados sobre esta materia / publicado por Real Decreto de S.M. la Reina N.tra S.ra

SignaturizadoTexto firmado por Francisco Fernandez del Pin

Ecos del naturalismo: la huella española en los personajes de El polvo y el oro de Julio Travieso (1993)

La novela El polvo y el oro (1993) del cubano Julio Travieso (La Habana, 1940) se erige como una de las fundamentales del llamado “periodo especial” de los años noventa del siglo XX y la primera década del XXI. Construida como una novela “total”, al estilo de las del boom de los años sesenta, se aleja de la moda de final de siglo consistente en describir superficialmente la época de hambre y escasez, de lucha por la supervivencia y de escepticismo en la Cuba revolucionaria que agoniza. Es, más bien, una novela coral que entronca con la narración histórica contemporánea (Eco, Graves, Yourcenar) o nueva novela histórica y que posee numerosos ecos del naturalismo cubano de principio de siglo, que indagaba en la identidad cubana y hacía referencia constantemente a la huella que los españoles han dejado en la isla desde la llegada de Colón.El polvo y el oro (1993), by Julio Travieso (La Havana, 1940), is one of the most important Cuban novels from the 90’s. This decade was named “periodo especial” (special period), when The Soviet Regime disappeared. For this reason, the economic aid from the old urss to the Caribbean island ended. El polvo y el oro was written as a “totalizing novel”, in a similar way to the novels of the Latin American Boom, from the sixties, and it is far beyond from other novels of its decade, dedicated to poverty, skepticism and the struggle for survival in a country with a political and economical dying system. Travieso’s work is an historical narration, like other new historical novels written by authors such as Eco, Yourcenar and Graves, with a remarkable impact of Cuban Naturalism from the beginning of 20th Century. This narrative is focused in the Cuban Identity, that is determined by the influence of the Spanish civilization in this island since the discovery of America until 20th Century