Induction of stimulative parthenocarpy in Vitis vinifera L.

Stimulative parthenocarpy was induced in two varieties of Vitis vinifera L. Flame Tokay and Rose Muscat (local variety) out of eight varieties studied.In F l a m e T o k a y the delay or inhibition of bhe abscission of the calyptra and parthenocarpic development of the berries, was obtained with pre-bloom treatments (3 days before beginning of bloom) of 4CPA 30 ppm + KGA3 30 ppm. Induction and growth ,of parthenocarpic berries was most pronounced after post-bloom sprays (7 days after the end of bloom) with BA 1500 ppm + KGA3 80 ppm or 4CPA 30 ppm. A parthenocarpic development of the berries was also obtained with postbloom treatments of KGA3 at concentrations of 50 to 100 ppm. BA (Benzyladenine) alone had only a slight effect on the development of parthenocarpic berries. However, the results were surprisingly satisfactory when applied in combination with gibberellin (KGA3 80 ppm) or auxins. Treatments at bloom or after bloom with BA 800 ppm + KGA3 80 ppm increased bhe number of berries and cluster weight. Applications of BA 800 ppm + KGA3 80 ppm to Rose Musca t at the beginning of bloom resulted in clusters with practically all berries seedless. The artificially accelerated growth of the berries may provoke abortion of all the recently fecundated ovules and the non viability of the not fecundated ones. Clusters of the treated plants with an average of 520 flowers originated 501 parbhenocarpic berries (96%), whereas the control with an average 635 flowers per cluster gave a percentage of seeded + seedless berries of 14% only {95 berries per cluster). BA applied with auxin or gibberellin-like substances in full-bloom or after bloom produced seedless berries, which were smaller in size than the seeded berries of unsprayed clusters

Non-oxidative conversion of methane with continuous hydorgen removal

The objective is to overcome the restrictions of non-oxidative methane pyrolysis and oxidative coupling of methane by transferring hydrogen across a selective inorganic membrane between methane and air streams, without simultaneous transport of hydrocarbon reactants or products. This will make the overall reaction system exothermic, remove the thermodynamic barrier to high conversion, and eliminate the formation of carbon oxides. Our approach is to couple C-H bond activation and hydrogen removal by passage of hydrogen atoms through a dense ceramic membrane. In our membrane reactor, catalytic methane pyrolysis produces C2+ hydrogen carbons and aromatics on the one side of the membrane and hydrogen is removed through an oxide film and combusted with air on the opposite side. This process leads to a net reaction with the stoichiometry and thermodynamic properties of oxidative coupling, but without contact between the carbon atoms and oxygen species

La comprensión de problemas de campo eléctrico en estudiantes universitarios: Aspectos de la instrucción en la organización de representaciones

Tesis de DoctoradoAutora: Gloria E. Alzugaray de la IglesiaDirector: Marco Antonio MoreiraCo-Directora: Marta B. MassaLugar: Universidad de Burgos, Espa&ntilde;aPrograma Internacional de Doctorado en Ense&ntilde;anza de lasCienciasFecha de defensa: 20 de enero de 2011</p

Fundamental studies of the mechanism of catalytic reactions with catalysts effective in the gasification of carbon solids and the oxidative coupling of methane. Quarterly report, October 1, 1994--December 31, 1994

This report describes research on the oxidative coupling of methane and catalysts involved in coal gasification. Topics include methane pyrolysis and catalysts, and magnetic properties of the coal gasification catalyst Ca-Ni-K-O system

A note on the invariant distribution of a quasi-birth-and-death process

The aim of this paper is to give an explicit formula of the invariant distribution of a quasi-birth-and-death process in terms of the block entries of the transition probability matrix using a matrix-valued orthogonal polynomials approach. We will show that the invariant distribution can be computed using the squared norms of the corresponding matrix-valued orthogonal polynomials, no matter if they are or not diagonal matrices. We will give an example where the squared norms are not diagonal matrices, but nevertheless we can compute its invariant distribution

Steady-state and transient catalytic oxidation and coupling of methane

This project addresses the conversion of methane from natural gas into ethane, ethylene and higher hydrocarbons. Our research explores the mechanistic and practical implications of carrying out the methane oxidative coupling reaction in reactor designs other than conventional packed-beds with co-fed reactants. These alternate reactor designs are needed to prevent the full oxidation of methane, which limits C{sub 2}, yields in methane oxidative coupling reactions. The research strategy focuses on preventing contact between the 0{sub 2} reactant required for favorable overall thermodynamics and the C{sub 2+} products of methane coupling. The behavior of various reactor designs are simulated using detailed kinetic transport models. These simulations have suggested that the best way to prevent high C0{sub 2} yields is to separate the oxygen and hydrocarbon streams altogether. As a result, the project has focused on the experimental demonstration of proton transport membrane reactors for the selective conversion of methane into higher hydrocarbons

Accurate PpT Data for Methane from (300 to 450) K up to 180 MPa

This paper reports PFT data measured with a high-pressure, single-sinker, magnetic-suspension densimeter (MSD) from (300 to 450) K up to 180 MPa. Our MSD technique yields accurate data, with less than 0.05 % relative uncertainty, over the pressure range of (10 to 200) MPa. The experimental data compare well to the Setzmann and Wagner equation of state as implemented in RefProp 8.0. These methane density data are consistent with the low range of pressure predicted by RefProp 8.0 that has a relative uncertainty of 0.03 % up to 12 MPa and 0.07 % up to 50 MPa. The density predictions of this model agree well with previous data at higher pressures. The equation predicts data with almost the same uncertainty as the experimental data up to 180 MPa. These PFT data also allow reliable determination of both second and third virial coefficients

Spatial distribution of Cydia fagiglandana (Zeller) in an exploited holm oak (Quercus ilex L.) forest.

Cydia fagiglandana (Zeller) (Lepidoptera: Tortricidae) is a carpophagous insect which affects the quality andviability of the fruits of beech, oak and chestnut trees. The majority of the works on this species in holm oak woodsdealt with assessing its damages. No investigations have yet been performed on the spatial distribution of this pest,although this element is one of the key features to take in account in order to develop proper integrated managementprograms. The present study, performed during a four years period in an exploited holm oak forest area in SouthernSpain, investigated the spatial distribution of C. fagiglandana integrating classic methods based on dispersion ratesand distribution fitting together with the elaboration of population density maps based on GIS. Our results showedthat the infestation rate progressively decreased from 0.339 in 2001 to 0.102 in 2004. Density maps for C. fagiglandanaalso show an heterogeneous and aggregated distribution of this insect and a spatio-temporal stability in this area. It isconcluded that during the four years of the study inter-specific competition with the weevil Curculio elephas was thefactor that most affected the spatial distribution of C. fagiglandana in the experimental plot

The dusty SF history of high-z galaxies, modelling tools and future prospects

We summarize recent advances in the determination of the cosmic history of star formation and other properties of high-z galaxies, and the relevance of this information in our understanding of the formation of structures. We emphasize the importance of dust reprocessing in the high--z universe, as demonstrated in particular by IR and sub-mm data. This demand a panchromatic approach to observations and suitable modelling tools. We spend also some words on expectations from future instruments.Comment: 8 pages, to be published in "The link between stars and cosmology", 26-30 March, 2001, Puerto Vallarta, Mexico, by Kluwer, eds. M. Chavez, A. Bressan, A. Buzzoni, and D. Mayy