Field evaluation of entomopathogenic nematodes against orchard pests

Survival of pest in micro-plot trials (container studies) or field plot trials was monitored after exposure to commercially used EPN strains. Experimental plots were artificially infested with pest larvae that naturally burrowed into the soil for diapause. Either larval mortality or adult emergence, was assessed to estimate the control effect of the EPN treatment. Here we present preliminary results from three ongoing projects

Discovery of the Vanadium Isotopes

Twenty-four vanadium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.Comment: to be published in At. Data. Nucl. Data Table

Non-interpenetrated metal-organic frameworks based on copper(II) paddlewheel and oligoparaxylene-isophthalate linkers: synthesis, structure and gas adsorption

Two metal–organic framework materials, MFM-130 and MFM-131 (MFM = Manchester Framework Material), have been synthesized using two oligoparaxylene (OPX) tetracarboxylate linkers containing four and five aromatic rings, respectively. Both fof-type non-interpenetrated networks contain Kagomé lattice layers comprising [Cu2(COO)4] paddlewheel units and isophthalates, which are pillared by the OPX linkers. Desolvated MFM-130, MFM-130a, shows permanent porosity (BET surface area of 2173 m2/g, pore volume of 1.0 cm3/g), high H2 storage capacity at 77 K (5.3 wt% at 20 bar and 2.2 wt% at 1 bar), and a higher CH4 adsorption uptake (163 cm3(STP)/cm3 (35 bar and 298 K)) compared with its structural analogue, NOTT-103. MFM-130a also shows impressive selective adsorption of C2H2, C2H4, and C2H6 over CH4 at room temperature, indicating its potential for separation of C2 hydrocarbons from CH4. The single-crystal structure of MFM-131 confirms that the methyl substituents of the paraxylene units block the windows in the Kagomé lattice layer of the framework, effectively inhibiting network interpenetration in MFM-131. This situation is to be contrasted with that of the doubly interpenetrated oligophenylene analogue, NOTT-104. Calculation of the mechanical properties of these two MOFs confirms and explains the instability of MFM-131 upon desolvation in contrast to the behavior of MFM-130. The incorporation of paraxylene units, therefore, provides an efficient method for preventing network interpenetration as well as accessing new functional materials with modified and selective sorption properties for gas substrates

In-Situ Nuclear Magnetic Resonance Investigation of Strain, Temperature, and Strain-Rate Variations of Deformation-Induced Vacancy Concentration in Aluminum

Critical strain to serrated flow in solid solution alloys exhibiting dynamic strain aging (DSA) or Portevin–LeChatelier effect is due to the strain-induced vacancy production. Nuclear magnetic resonance (NMR) techniques can be used to monitor in situ the dynamical behavior of point and line defects in materials during deformation, and these techniques are nondestructive and noninvasive. The new CUT-sequence pulse method allowed an accurate evaluation of the strain-enhanced vacancy diffusion and, thus, the excess vacancy concentration during deformation as a function of strain, strain rate, and temperature. Due to skin effect problems in metals at high frequencies, thin foils of Al were used and experimental results correlated with models based on vacancy production through mechanical work (vs thermal jogs), while in situ annealing of excess vacancies is noted at high temperatures. These correlations made it feasible to obtain explicit dependencies of the strain-induced vacancy concentration on test variables such as the strain, strain rate, and temperature. These studies clearly reveal the power and utility of these NMR techniques in the determination of deformation-induced vacancies in situ in a noninvasive fashion.

Discovery of the Barium Isotopes

Thirty-eight barium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.Comment: to be published in At. Data Nucl. Data Table

The three-stage petrochemical evolution of the Steens Basalt [southeast Oregon, USA] compared to large igneous provinces and layered mafic intrusions

The Steens Basalt, southeast Oregon, USA, initiated at 17 Ma as the earliest pulse of the Columbia River Flood Basalt of the northwestern USA. New and existing stratigraphically controlled data reveal temporal changes in lava flow character, and whole-rock and mineral compositions, which we use to evaluate how the balance of magma differentiation processes change in time. Temporal petrochemical variations in the Steens Basalt are analogous to the transition from Imnaha Basalt to Grande Ronde Basalt units of the Columbia River Flood Basalt and have parallels to the temporal evolution of the Deccan and Siberian traps, in India and Russia, respectively, as well as to the stratigraphic sequences of the Bushveld, of South Africa, and Stillwater, in southern Montana, USA, layered mafic intrusions. The excellent stratigraphic control from the Steens Basalt provides a detailed record for comparison across this variety of large mafic systems, providing ability to focus on commonalities among differentiation processes in time. Chemostratigraphic excursions and volcanological characteristics in the Steens Basalt record a three-stage history. A minimally exposed early stage preserved in the lower A Steens Basalt section is characterized by heterogeneity (3–8 wt% MgO) collapsing to homogeneity (~5 wt% MgO), suggesting crystal fractionation outpaces recharge. Sparse weathering horizons indicate some time elapses between eruptions. The second stage, lower B Steens Basalt, is volumetrically dominant and represents waxing of the basaltic pulse. Flows are stacked immediately upon one another without evidence of weathering or intervening sedimentary horizons, indicating high-eruptive frequency. Compositions oscillate over a ΔMgO of ~4–5 wt% between low- and high- MgO basalt, both of which become more magnesian up section, signaling a period dominated by recharge. This stage closes with declining oscillations to produce homogeneous compositions (6–8 wt% MgO). The waning stage of eruption is represented by the upper Steens Basalt section, where thin intercalated weathering horizons occur especially high in the section. The upper Steens Basalt is characterized by overall declining MgO and increasing incompatible element concentrations confirming the dominance of crystal fractionation accompanied by crustal assimilation. In detail, the upper Steens Basalt initiates with a small stack of heterogeneous flows (5–8 wt% MgO), followed by a period of relatively homogeneous flows (~6 wt% MgO) and closes with highly variable basalts to trachybasaltic andesites. These compositional characteristics coupled with a change in average flow thickness from lower to upper Steens Basalt of5–10 m illustrate a shift to more silicic compositions and higher viscosity up section. The chemical changes up section in other large igneous provinces record similar variations in differentiation processes through time, suggesting that these large volume systems share similar evolutionary histories: the earliest records suggest the magmatic systems are initially more ephemeral and compositionally variable as magma traverses relatively cool crust. With waxing, a transition to regimes of high thermal and mass input results in a stage where recharge outpaces crystal fractionation. Thermal priming of the crust during these events coupled with waning input yields magmas in which fractionation plus crustal assimilation dominates over recharge late in the system; pulses of later stage felsic magmatism in many large mafic provinces are consistent with this evolution. Using layered mafic intrusions as an analog for intrusive, cumulus-dominated residua of voluminous fractionation, as well as oceanic large igneous provinces as an analog for total magma volumes in continental flood basalt regimes, leads to the suggestion that 50%–85% of the total magma volume in a flood basalt remains in the crust, effectively remaking the crust in these regions

Structure of the Electrochemical Interface:Ag(hkl)) in an Alkaline Electrolyte

The structure of the electrochemical double layer at the interface between Ag­(hkl) electrodes and 0.1 M NaOH electrolyte has been probed using in situ surface X-ray diffraction (SXRD) measurements. The three low-index Ag­(hkl) surfaces were prepared and characterized under ultra-high vacuum (UHV) conditions before being transferred into the electrochemical environment. Crystal truncation rod (CTR) measurements were made at negative potentials (just negative of the pzc), where there is no specific adsorption onto the electrode surfaces, and at more positive potentials, where hydroxide species is specifically adsorbed. The measurements quantify the relaxation at the metal electrode surfaces and, through the specular CTR, give information about layering on the electrolyte side of the interface. Strong layering effects are observed on the Ag(111) and Ag(110) surfaces, whereas on Ag(001) the layering is much weaker and we attribute this to the symmetry mismatch to the adsorbing water network. The effect of saturating the electrolyte with carbon monoxide (CO) was also examined, and structural changes were only observed on the Ag(110) surface. The changes observed suggest a stabilization of a coadsorbed CO–OH adlayer due to charge redistribution that delays the onset of CO oxidation