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Alfalfa is a reservoir providing natural enemies to adjacent crops. However, whether these crops act only as receptors or also as donors is unknown. The pattern of movement between alfalfa and maize of Orius majusculus, Orius niger and Nabis provencalis and the role of both crops as "donor" or "receptor" were inferred through carbon and nitrogen stable isotope analysis. Results show that all heteropteran species are able to move between crops, but the predators' movement is species specific and the role of alfalfa and maize as "donor" or "receptor" varies. The movement is also affected by crop management practices such as alfalfa cutting. All heteropterans that colonized maize at its early stage came from alfalfa, but N. provencalis also moved back to alfalfa from maize. Alfalfa cutting triggers movement of heteropterans to maize, but the time when this practice is performed also affects the movement. Alfalfa cutting did not have consequences on the recolonization of alfalfa, and some of the heteropterans found during the alfalfa regrowth period seem to have remained within alfalfa (mainly N. provencalis) while others came from maize (mainly O. majusculus and O. niger). When maize was harvested or dry, O. majusculus moved to alfalfa later than the other two predators. Due to the movement capacity of heteropterans between alfalfa and maize and the variable role of both crops as "donor" or "receptor", conservation biological control could be enhanced by including adjacent fields of alfalfa and maize or a mosaic of both crops at farm and landscape levels. [ABSTRACT FROM AUTHOR]

Orius majusculus Reuter (Heteroptera: Anthocoridae) is the most common and abundant generalist predator in Spanish maize crops and is sensitive to drastic changes in weed density. We carried out a 2-year study in the NE Iberian Peninsula to examine the dispersal of O. majusculus in maize plots with moderately high and low weed density. Insects were collected using yellow sticky traps and/or a bug-vac aspirator. Dispersal was assessed using rubidium as a marker. Dispersal rate of O. majusculus differed between sampling periods, with a maximum between the 16 unfolded leaves (V16) to grain milky (R3) maize growth stages. However, we detected no differences in the distance moved by male and females of O. majusculus from rubidium-marked areas in plots with moderately high or low weed density suggesting that changes in weed density do not affect the dispersal of O. majusculus within a maize field. [ABSTRACT FROM AUTHOR]

Abstract: HZSM-5 zeolite was found to be a very stable catalyst for the ethanol transformation into hydrocarbons at 350°C and 30bar total pressure. It was found to maintain high activity for C3+ hydrocarbons formation with time-on-stream in spite of a near total loss of Brønsted acidity, 92% loss of microporosity and high coke content deposited inside its micropore volume. The same solid, passivated with TEOS was tested in the same conditions and it was found that the treatment slightly improved the catalytic performance of the zeolite, even if similar losses of acidity and microporisty were determined after reaction. This shows that C3+ hydrocarbons’ formation does not occur at the external surface. Alkyl aromatic hydrocarbons were found occluded in the zeolite structure after reaction, detected by IR spectroscopy analysis and by CH2Cl2 extraction after solubilization of the structure with HF solution. EPR-CW analysis of both coked samples proved existence of free radicals. This last technique could provide us further enlightening of the ethanol transformation mechanism. [Copyright &y& Elsevier]

Abstract: Ethanol transformation into higher hydrocarbons in one step by heterogeneous acid catalysis was studied, under 350°C and 30bar of total pressure. A comparison was established among three zeolites (HFAU, HBEA and HZSM-5) having the same quantity of Brønsted acid sites but possessing different pore architectures. Large pore HFAU and HBEA zeolites gave mainly increasing yield of ethylene and diethyl ether with time-on-stream, due to the deactivation of the strongest acid sites and only a low quantity of C3+ hydrocarbons. This was explained by a faster deactivation of large pore zeolites due to fast coke formation which rapidly eliminates strong Brønsted acid sites, required for the transformation of ethylene into higher hydrocarbons. These coke molecules were identified as being polyaromatic compounds. Medium pore zeolite HZSM-5 showed an important formation of C3+ hydrocarbons (mostly C5–C11 compounds) and very small amounts of ethylene and diethyl ether. For this zeolite, after 16h reaction, there was still complete ethanol transformation into C3+ hydrocarbons, even though a 55% loss of microporosity and 94% loss of Brønsted acidity were observed. On HZSM-5 the deactivation is slower and the formation of C3+ hydrocarbons was observed even when the catalyst was saturated with coke molecules (high activity for the hydrogen transfer reactions). It could be possible, that for this zeolite, reaction occurs at the pore mouth of the channel. [Copyright &y& Elsevier]

• Dicyphus bolivari and D. errans are predators augmented in greenhouses for pest control. • Odors of uninfested tomato, cucumber, and pepper did not attract either predator. • Marigold plants did not result attractive for the two predators even if they are infested by whiteflies. • However, tomato plants with predator eggs became attractive to that predator. • Tomato was preferred to cucumber or sweet pepper for oviposition. [ABSTRACT FROM AUTHOR]

The Smart CutTM technology has been used for LiTaO3 layer transfer. A 3-inch full wafer single-crystal LiTaO3 layer onto a carrier wafer comprising a metallic electrode is reported. [ABSTRACT FROM AUTHOR]

Crack propagation in implanted silicon for thin layer transfer is experimentally studied. The crack propagation velocity as a function of split temperature is measured using a designed optical setup. Interferometric measurement of the gap opening is performed dynamically and shows an oscillatory crack "wake" with a typical wavelength in the centimetre range. The dynamics of this motion is modelled using beam elasticity and thermodynamics. The modelling demonstrates the key role of external atmospheric pressure during crack propagation. A quantification of the amount of gas trapped inside pre-existing microcracks and released during the fracture is made possible, with results consistent with previous studies. [ABSTRACT FROM AUTHOR]

Abstract: HBEA (11) zeolite was deactivated rapidly by coking during the ethanol transformation into hydrocarbons, at 623K and 30bar. The nature of carbonaceous deposit was studied, after zeolite dissolution by hydrofluoric acid both by gas chromatography coupled with mass spectrometry and by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). The coke on the external zeolite surface was characterized directly on the spent catalyst by laser desorption/ionization time of flight mass spectrometry (LDI-TOF MS). The coke species were identified and classified into 17 families following their unsaturation number (4–23). The coke was polyaromatic, and it was very alkylated (methyl, ethyl, and propyl groups). It is compounded of alkylbenzenes, mainly hexamethylbenzene (HMB), and alkyl-pyrenes, located within the zeolite pore, which could migrate to the external zeolite surface and grow into polyaromatic compounds constituted up to eight aromatic rings and up to 40 carbon atoms. Pulsed electron paramagnetic resonance spectroscopy measurements and molecular simulation by using Cerius2 software have shown that HMBs are distant of 0.6nm inside the zeolite pores. [Copyright &y& Elsevier]

The formation and detailed characterisations of a 200 mm germanium-on-insulator substrate made from germanium bulk material as donor wafer using the Smart CutTM technology is reported. Detailed characterisations of final GeOI structures are presented: final roughness, defectivity evaluation, thickness measurement, and electrical characterisation. [ABSTRACT FROM AUTHOR]

The interaction of a propagating crack in implanted silicon with self-emitted acoustic waves results in periodic patterns on fractured surfaces. Direct measurement of the acoustic emission ahead of the fracture front shows the emergence of dominant acoustic frequency related to the crack velocity. It is shown that the surface modifications are made of roughness modulations due to periodic deviations of the crack front. A physical mechanism explaining the pattern formation is proposed, well in agreement with the observed pattern wavelengths. [ABSTRACT FROM AUTHOR]