Factors affecting rind pitting in the mandarin hybrids "fortune" and "nova". The influence of exogenous growth regulators

The commercialization of the mandarin hybrids "Fortune" and "Nova" is hindered by the development of cold-induced pitting in the fruit rind which may develop either in the orchard or during storage and transport. In the late cropping cultivar "Fortune", the pitting develops on tree during the winter months and affects mainly the exposed fruit from the north-west quadrant of the tree. The induction of symptoms under uniform conditions in the cold-room reveals differences in the susceptibility to chilling injury among the fruits and the fruit sides. The green fruit is not susceptible. Susceptibility develops as pigmentation progresses, and it is higher for the exposed than for the non-exposed (covered by the foliage) fruits. The application of GA3 at colour-break delays pigmentation and retards the development of susceptibility. The waxing of the fruit offers some protection to cold in the cold-room. However, the incidence of pitting is not related to the wax content of the fruit rind and the application of a wax coverage on tree had only a marginal protective effect. No pitting is usually found on tree in the fruit of the early ripening "Nova" cultivar, which is usually harvested before the winter chilling. The pitting develops during cold storage (8-10 C), and is reduced by GA3 application at colour break, an effect related to the delay in rind pigmentation.info:eu-repo/semantics/publishedVersio

Two-dimensional molecular para-hydrogen and ortho-deuterium at zero temperature

We study molecular para-hydrogen (p-${\rm H_{2}}$) and ortho-deuterium (o-${\rm D_{2}}$) in two dimensions and in the limit of zero temperature by means of the diffusion Monte Carlo method. We report energetic and structural properties of both systems like the total and kinetic energy per particle, radial pair distribution function, and Lindemann's ratio in the low pressure regime. By comparing the total energy per particle as a function of the density in liquid and solid p-${\rm H_{2}}$, we show that molecular para-hydrogen, and also ortho-deuterium, remain solid at zero temperature. Interestingly, we assess the quality of three different symmetrized trial wave functions, based on the Nosanow-Jastrow model, in the p-${\rm H_{2}}$ solid film at the variational level. In particular, we analyze a new type of symmetrized trial wave function which has been used very recently to describe solid $^{4}$He and found that also characterizes hydrogen satisfactorily. With this wave function, we show that the one-body density matrix $\varrho_{1} (r)$ of solid p-${\rm H_{2}}$ possesses off-diagonal long range order, with a condensate fraction that increases sizably in the negative pressure regime.Comment: 11 pages, 9 figure

Equation of state of low--density neutron matter and the 1S0^1S_0 pairing gap

We report results of the equation of state of neutron matter in the low--density regime, where the Fermi wave vector ranges from $0.4 fm^{-1} \leq k_F \leq 1.0 fm^{-1}$. Neutron matter in this regime is superfluid because of the strong and attractive interaction in the $^1S_0$ channel. The properties of this superfluid matter are calculated starting from a realistic Hamiltonian that contains modern two-- and three--body interactions. The ground state energy and the $^1S_0$ superfluid energy gap are calculated using the Auxiliary Field Diffusion Monte Carlo method. We study the structure of the ground state by looking at pair distribution functions as well as the Cooper-pair wave function used in the calculations.Comment: 12 pages, 7 figure

Solidification of small para-H2 clusters at zero temperature

We have determined the ground-state energies of para-H$_2$ clusters at zero temperature using the diffusion Monte Carlo method. The liquid or solid character of each cluster is investigated by restricting the phase through the use of proper importance sampling. Our results show inhomogeneous crystallization of clusters, with alternating behavior between liquid and solid phases up to N=55. From there on, all clusters are solid. The ground-state energies in the range N=13--75 are established and the stable phase of each cluster is determined. In spite of the small differences observed between the energy of liquid and solid clusters, the corresponding density profiles are significantly different, feature that can help to solve ambiguities in the determination of the specific phase of H$_2$ clusters.Comment: 17 pages, accepted for publication in J. Phys. Chem.

Atomic kinetic energy, momentum distribution and structure of solid neon at zero-temperature

We report on the calculation of the ground-state atomic kinetic energy, $E_{k}$, and momentum distribution of solid Ne by means of the diffusion Monte Carlo method and Aziz HFD-B pair potential. This approach is shown to perform notably for this crystal since we obtain very good agreement with respect to experimental thermodynamic data. Additionally, we study the structural properties of solid Ne at densities near the equilibrium by estimating the radial pair-distribution function, Lindemann's ratio and atomic density profile around the positions of the perfect crystalline lattice. Our value for $E_{k}$ at the equilibrium density is $41.51(6)$ K, which agrees perfectly with the recent prediction made by Timms {\it et al.}, $41(2)$ K, based on their deep-inelastic neutron scattering experiments carried out over the temperature range $4 - 20$ K, and also with previous path integral Monte Carlo results obtained with the Lennard-Jones and Aziz HFD-C2 atomic pairwise interactions. The one-body density function of solid Ne is calculated accurately and found to fit perfectly, within statistical uncertainty, to a Gaussian curve. Furthermore, we analyze the degree of anharmonicity of solid Ne by calculating some of its microscopic ground-state properties within traditional harmonic approaches. We provide insightful comparison to solid $^4$He in terms of the Debye model, in order to size the relevance of anharmonic effects in Ne.Comment: 20 pages, 7 figures. To be published in Physical Review

Los suelos de la provincia de Granada y su posible incidencia en la fertilidad del olivo: II. Suelos pardo calizos

Se estudian suelos de olivar que presentan un horizonte B de propiedades y morfología muy variadas. El comportamiento frente al olivo está relacionado con dicho horizonte B y la presencia en algunos casos de un horizonte cálcico. Estos caracteres y el clima son los factores, independientemente del humano, responsables de la fertilidad del olivar desarrollados sobre ellos.At the present paper it has been studied 14 soils profiles under olive trees which present a B horizon with properties and morphology very different. The relation-ships between the culture of the olive-trees and the B hor1- zon are very straight so as in sorne cases the presence of a calcic horizon. These characters and the climatology, besides the human factor, are the factors responsibles of the fertility of the olive-trees developed on these soils

Los suelos de la provincia de Granada y su posible influencia en la fertilidad del olivo. III. Suelos pardos rojos calizos y tierras pardas

Se estudian algunos suelos pardos rojizos y tierras pardas meridionales de la provincia de Granada, dedicadas al cultivo del olivo, detallando la posible correlación existente entre suelo y planta.It have been studied some brown-reddish soils and meridional brown soils of the Granade provínce which are dedicated to the culture of the olive-trees and we have pointed out about the possible correlation between soil and plant

Los suelos de la provincia de Granada y su posible incidencia en la fertilidad del olivo. I. – Suelos rendsiniformes y vertisoles

Se agrupan en el presente trabajo, primero de una serie de cuatro, dedicado al estudio de los suelos con olivar en la provincia de Granada, a aquellos suelos con perfil poco desarrollaDo, que pueden ser clasificados como suelos rendsiniformes. vertisuelos y sus integrados. Se pone de manifiesto la complejidad y ambigüedad de los términos utilizados en algunas de las clasificaciones más usuales y se toma la de la FAO como clasificación de referencia. La relación suelo fertilidad, según les perfiles estudiados es la siguiente: Regosoles → Vertisoles → Serosoles → Yermosoles Los factores ,condicionantes son el espesor del suelo, la presencia de costra yesosa más o menos superficial, hidromorfia y climatología de la zona.We have studied at the present papel" four types of soils with very litle developed pro fiJe s which may be classified as Rendsina soils, VertisoIs and their integrades. The relation soil/fertility according to the soils studied is as fallaws: Regosols → Vertisols → Xerosols → ·ermosols The main factors which influence the soil fertility are: soils depth, the presence of gypsum cousts more or less near surface, hidromorphic conditions and the climatologie of the zone

Spiked oscillators: exact solution

A procedure to obtain the eigenenergies and eigenfunctions of a quantum spiked oscillator is presented. The originality of the method lies in an adequate use of asymptotic expansions of Wronskians of algebraic solutions of the Schroedinger equation. The procedure is applied to three familiar examples of spiked oscillators

Bifurcation Diagram for Compartmentalized Granular Gases

The bifurcation diagram for a vibro-fluidized granular gas in N connected compartments is constructed and discussed. At vigorous driving, the uniform distribution (in which the gas is equi-partitioned over the compartments) is stable. But when the driving intensity is decreased this uniform distribution becomes unstable and gives way to a clustered state. For the simplest case, N=2, this transition takes place via a pitchfork bifurcation but for all N>2 the transition involves saddle-node bifurcations. The associated hysteresis becomes more and more pronounced for growing N. In the bifurcation diagram, apart from the uniform and the one-peaked distributions, also a number of multi-peaked solutions occur. These are transient states. Their physical relevance is discussed in the context of a stability analysis.Comment: Phys. Rev. E, in press. Figure quality has been reduced in order to decrease file-siz