Extent Of Splitting Research Articles

Identification of quantitative trait loci for cane splitting in red raspberry (Rubus idaeus)

Cane splitting, a normal feature of raspberry growth, can lead to plant infestation by cane midge followed by fungal infection, with losses in yield of up to 50 % if left untreated. The extent of splitting in the Latham × Glen Moy reference mapping population was assessed over six years and in three environments and quantitative trait loci (QTL) were identified across linkage groups (LG) 2, 3, 5 and 6. Cane splitting QTL on LG 3 and 5 co-locate with QTL for plant vigour. The cane splitting QTL on LG 6 is associated with the QTL for resistance to root rot caused by Phytophthora rubi. Broad-sense heritability for cane splitting ranged from 25.6 % in 2007 to 49.1 % in 2008 in this population. Season and environment were also found to influence cane splitting in this population. Several genes involved in general plant growth and in defence responses lie within these QTL. This is a first step towards identifying the genetic basis of cane splitting in raspberry and the development of genetic markers for use in raspberry breeding programmes.

Novel tetracyanoplatinates with the larger Ln3+ ions: Synthesis, structures, and photoluminescence properties of KLn[Pt(CN)4]2·8.75H2O (Ln = La, Pr, Nd)

The reaction of the larger Ln3+ ions with K2Pt(CN)4·3H2O results in the formation of the crystalline coordination compounds KLn[Pt(CN)4]2·8.75H2O (Ln=La, Pr, Nd). The structures of these compounds have been determined by single-crystal X-ray diffraction and found to be isostructural. Crystallographic data (Mo Kα, λ=0.71073Å) for the representative La compound (LaPt): orthorhombic, Fdd2, a=19.5826(3)Å, b=26.8725(7)Å, c=34.9729(8)Å, V=18403.9(7)Å3, Z=32, R1(I>2σ(I))=0.0217. The structures of the compounds contain nearly planar two-dimensional lanthanide tetracyanoplatinate layers formed from the trans-bridging of the Ln3+ cations by tetracyanoplatinate (TCP) anions. The layers are graphitic in nature, containing fused hexagons that form the layered 2-D topology. Furthermore, they stack in an ABCDEFGHA pattern, are separated by an average distance of 3.3591(7)Å, and contain multiple interlayer Pt⋯Pt interactions that give rise to one-dimensional stacks of TCP. All three compounds display strong broad-band luminescence in the visible region originating from the TCP stacks. At room temperature, LaPt illustrates strong green emission centered at 508nm upon excitation in the UV. The broad emission splits into a stronger band at 534nm and a higher energy band at 478nm upon cooling the crystals to 77K. The extent of splitting was found to depend on the excitation wavelength. Similar spectral features at both room temperature and 77K are observed in the PrPt system. A characteristic feature of NdPt is that the TCP-based broad emission is significantly quenched due to reabsorption of the emitted light by the Nd3+ ion, indicating the dominance of a radiative process within the system.

Ab Initio Multireference Investigation of Disjoint Diradicals: Singlet versus Triplet Ground States

We present improved virtual orbital (IVO) complete active space (CAS) configuration interaction (IVO-CASCI) and IVO-CASCI-based multireference Møller-Plesset perturbation theory (MRMPPT) calculations with an aim to elucidate the electronic structure of tetramethyleneethane (TME) in its lowest singlet and triplet state and to quantify their order and extent of splitting. The potential surfaces of singlet and triplet states for the twisting of TME are also studied. We found that the triplet state is higher in energy than the singlet one in the whole range of twisting angles with the energy gap minimum at a twisting angle of about 45°. Harmonic vibrational frequencies of TME have also been calculated for both the states. We also report the ground to first excited triplet state transition energies. Our results are analyzed with respect to the results available in the literature to illustrate the efficacy of our methods employed. We also demonstrate that the spin character of the ground state of disjoint, TME-like diradicals can be manipulated by using appropriate selection of annulenic spacer to separate the allyl groups of TME.

Physical properties of the dense Kondo compoundsYbXCu4 (X=Au,Ag, In, Cd, Tl, and Mg) probed by63CuNMR

We have carried out a systematic 6 3 Cu nuclear magnetic resonance (NMR) study on a set of ytterbium-based Kondo compounds YbXCu 4 with X=Au, Ag, In, Cd, Tl, and Mg. Splitting of the central NMR line due to a second-orderelectric-quadrupole interaction is of the order of magnitude of axial Knight shift, and the extent of splitting is controlled by changing applied field H. From the splitting of the central line, we have succeeded to deduce the values of both isotropic Knight shift K i s o and axial Knight shift K a x , taking a value of electric-quadrupole frequency determined by pure quadrupole resonance of 6 3 Cu, K i s o versus magnetic susceptibility Χ plots for each of the compounds with X=Au, Ag, and In are roughly on a straight line. For YbAgCu 4 (Kondo temperature T K ∼100 K), both K i s o and the unit-cell volume v c reach a local minimum around 40 K. We have found a linear relation between K i s o and v c below 100 K, similar to that observed in YbInCu 4 , indicating that the nonmagnetic behavior at low temperatures can be ascribed mainly to the Kondo volume expansion. In contrast, K i s o versus Χ plots for YbCdCu 4 (T K ∼220 K) and YbMgCu 4 (T K ∼860 K) exhibit somewhat complex behavior: hyperfine field H h f markedly increases coincident with the saturated behavior of Χ for X =Cd below ≃140 K, and with the decrease in Χ for X=Mg below ∼260 K. H h f originates mainly from transferred hyperfine coupling between Cu nucleus and Yb 4f moment, and the large increase in H h f is conjectured to result from a variation of crystal-electric-field interactions as the system transforms into a mixed-valence state. The variation with the species of X atoms of temperature-independent on-site contribution K s to the Knight shift is found to correlate with that of the electronic specific heat coefficient y (except for X=Cd), each of which gives a measure of the density of states of conduction sf resonance bands. Finally, using the values of K s , y, and T K , we have proposed a phase diagram for YbXCu 4 series, which corresponds to Doniach's phase diagram.

A spectroscopic study of the effect of the trivalent cation on the thermal decomposition behaviour of Co-based hydrotalcites

Various correlations between the size of the trivalent cation (Al, Ga, Fe, and Cr) and the structural characteristics and decomposition behavior of Co-based hydrotalcites (Co/M3+ = 3) have been identified. In situ IR spectra (by the relative ratio of the amount of carbonate in low and high symmetry) and thermogravimetric analyses show that the larger the trivalent cation, the lower the relative amount of water in the interlayer space of the as-synthesized material. Removal of interlayer water upon decomposition induces a symmetry loss of the carbonate groups, leading to splitting of the ν3 vibrational mode of the carbonate groups at elevated temperatures. The extent of splitting was found to continuously decrease as a function of increasing cation size, which suggests a decreasing degree of interaction of the carbonate groups with remaining OH groups in the brucite-like layers. However, the stability of the carbonates in the temperature range of 200–250 °C shows an opposite trend, and is apparently dependent on other factors, such as the stability of the hydroxides and the layered structure itself, as well as direct interactions of carbonate with the metal ions. Dehydroxylation of the brucite-like layers, followed by complete carbonate decomposition are the final stages leading to the formation of mixed metal oxides.

Some studies on the impact behavior of banded microalloyed steel

Microalloyed steels are used in automobile industries, offshore platforms and in structural applications. It is essential to establish a relation between service consition such as temperature, loading rate and fracture behavior of the steel. Impact study on new material is very handy to understand the mechanicl properties in a rapid and inexpensive way. The present investigation aims to assess impact toughness (CVN), ductile brittle transition temperature (DBTT, 25J), and initiation dynamic fracture toughness ( J ld ∗ ) of the indigenously developed microallayed seel. The steel has shown banding with alternate layers of ferrite and pearlite. The banding concentration (ferrite bands per mm) has been altered by heat treatment. Presence of banding has given spikes and splits in impact fracture. Change in banding concentration has affected DBTT of the steel, upper shelf energy and the extent of splitting. A model of crack divider with respect to the present microstructure has been analyzed. Banding in divider orientation improves the impact as well as initiation dynamic fracture toughness of the steel. The effect of temperature on splitting is also discussed. Splits in fractured surface disappear with decreasing temperature and higher numbers of splits yield lower toughness. Further, initiation dynamic fracture toughness is calculated for all temperatures and correlated with impact toughness.

Nonrigid molecule effects on the energy levels of XeF6

AbstractThe geometric and electronic structure of XeF6 is not yet fully understood, even though most of the means of structure determination available to the chemist have been employed in an effort to describe the molecule. We suggest that many of the experimental anomalies and theoretical difficulties arise from the possibility of rapid polytopal rearrangement in this system, and put forward in this report an analysis which accommodates the experimental data. We show that easy rearrangement produces substantial splittings in rigid‐molecule energy levels, and with the aid of Longuet‐Higgins group theory developed expressly for flexible molecules, compute energy‐level schemes for a set of plausible rearrangement modes. By appropriate choice of parameters specifying the extent of splitting, we match the reported infrared and Raman spectra, and their temperature dependence. The puzzling “time lag” in the Raman (but not the infrared) spectrum is tentatively ascribed to selective relaxation of Raman‐active vibrational modes.

Selection of Eucalypt Plus Trees with Regard to Splitting in the Sawn Timber / SELEKSIE VAN EUCALYPTUS-PLUSBOME MET BETREKKING TOT SPLITSING IN DIE GESAAGDE HOUT

ABSTRACT A practical method in use in South Africa for quantifying the extent of splitting in the timber of the genus Eucalyptus in order to determine minimum standards for selection purposes, is explained. The standards are used to assist in the choice of phenotypes, the progeny of which it is hoped will produce timber which splits less.

655. The effect of pH on the extent of splitting or clumping of fat globules caused by agitation of hot cream

The effect of pH on the extent of splitting and clumping of globules in hot cream agitated by treatment in a Vacreator, by vigorous mechanical stirring or by simple aeration has been investigated. The size distribution of globules was determined in cream before and after treatment either by the microscopic method or by a rapid method involving separation of small and large globules by centrifuging and gravity creaming respectively.It was found that at pH 8 splitting of globules was at a maximum and clumping at a minimum. As the pH of the cream to be treated was lowered towards pH 6, the amount of splitting decreased and clumping increased. The ‘clumping’ of globules in cream during single-stage homogenization was also increased as the pH was lowered.Practical applications of the observations are suggested.The thanks of the author are due to Mr J. A. Singleton, superintendent and Mr B. Le Heron, buttermaker of The Dairy Research Institute (N.Z.) experimental factory, for arranging and carrying out the Vacreator treatment of cream; to Dr F. H. McDowall for helpful advice and criticism, and to Miss R. P. Johnson for assistance with microscopic and analytical work.