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Abstract: SiO x N y /high-κ dielectric stack will soon replace the conventional SiO x N y -based dielectric stacks in the future generations of flash memory cells. Characterizing and reducing electron traps in the high-κ layer is an important task, as the large trap density may limit the memory retention via the trap-assisted tunneling. Since the Post-deposition Annealing (PDA) has great impact on the microstructure of high-κ dielectric, it is important to understand how PDA affects the properties of electron traps, such as the trap density, energy and spatial distributions. It is demonstrated in this paper that, by using a recently developed two-pulse C–V measurement technique, the energy and spatial distributions of electron traps throughout the SiO2/high-κ stack can be characterized, and PDA temperatures have different impacts on traps at different energy levels and spatial locations. [Copyright &y& Elsevier]

The mortality effects of crofton weed (Ageratina adenophora, (Asteraceae)) acetone extract and biogas fermentation residue on the cabbage aphid Brevicoryne brassicae, and the risk posed to its parasitoid Diaeretiella rapae, were studied. Laboratory trials demonstrated the insecticidal activity of both substances, and this was confirmed by field experiments in which reductions of 73 and 71% aphid populations were recorded 3 days after treatment for the acetone extract and the biogas fermentation residue, respectively. The results of a laboratory contact toxicity test on inert substrates for parasitoid adults, and calculation of the Hazard Quotient (HQ) ratio, indicate a low risk for D. rapae, with HQ being consistently below the trigger value of 2. [ABSTRACT FROM AUTHOR]

Abstract: A La2NiO4/ZSM-5 catalyst was prepared by the sol–gel method, which ensured high dispersion of the metal and high activity in the CO2 reforming of methane. The catalytic performance, catalyst stability and coke deposition as well as the influence of the doped La species on the Ni/ZSM-5 catalyst were investigated. The results show that the conversion of CO2 and CH4 to syngas and the selectivity of CO and H2 observed over the La2NiO4/ZSM-5 catalyst were significantly higher than those over a Ni/ZSM-5 or La2NiO4/γ-Al2O3 catalyst. Such results suggest that the doping of the rare earth ion (La3+) in the ZSM-5 not only enhanced the stability of the catalyst, but also increased the catalytic activity. In addition, the catalysts were characterized by X-ray diffraction (XRD), BET and thermogravimetic and differential thermal analysis (TG/DTA). The X-ray diffraction (XRD) studies revealed that the prepared catalyst, La2NiO4, exhibited a typical spinel structure and was uniformly dispersed both on the surface and in the ZSM-5 zeolite channels. During the CO2/CH4 reforming, the La2O3 generated from the La2NiO4 decomposition was transformed into La2O2CO3 in an atmosphere of CO2, which promoted CO2 adsorption on the surface of the catalyst. The TG/DTA results indicate that the amount of carbon deposition on the La2NiO4/ZSM-5 catalyst was smaller than the amount on the Ni/ZSM-5 catalyst, and that there were at least two kinds of carbon deposition on the used La2NiO4/ZSM-5 catalyst. However, only one kind of carbon deposition existed on the used Ni/ZSM-5 catalyst. [Copyright &y& Elsevier]

Abstract: The recent development of silicon-based microreactors requires conventional catalyst carriers to be trimmed down to the sub-micrometer regime while keeping their complex geometrical shapes unchanged. In this work, we use a “top-down” etching approach to fabricate Al2O3 nano-trilobe carriers from the inter-channel parts of pseudo-hexagonally arranged one-dimensional channels of anodic alumina membranes. With a dilute NaOH (0.04M) etchant and prolonged etching time (1.5h), highly regulated Al2O3 nanocarriers have been prepared into two major forms: well-aligned (bundles) and freestanding trilobes. It has been found that the Al2O3 nano-trilobes are generated only on the upward facing of the membranes owing to the support provided by less etched membrane underneath and a less vibrant region in fluid exchange. The etching process can be described as a nucleophilic reaction that involves an attachment of hydroxyl ions to Lewis acid sites of aluminum cations. The amorphous as-prepared nano-trilobes can be further heat-treated to any crystallographic phases. For example, phase pure polycrystalline θ-Al2O3 nano-trilobes have been prepared at 1000°C in laboratory air. Future applications of these nanocarriers have also been discussed. [Copyright &y& Elsevier]

Abstract: The ternary oxide Li6Gd(BO3)3:Ce crystals with dimensions up to Ø14×100mm3 were prepared by the modified Bridgman method. The crystallinity of crystal was measured using X-ray rocking curve analysis. The composition of the inclusions existing in the crystal was measured by electronic microprobe. The optical properties at room temperature were investigated by transmittance spectra and X-ray stimulated luminescence spectra (XSL). [Copyright &y& Elsevier]

Double-C60-end-capped poly(ethylene oxide) (FPEOF) was reinforced with acid-treated multi-walled carbon nanotubes (MWNTs). The storage modulus of FPEOF was significantly enhanced, whereas the crystallization behavior was not significantly affected upon the incorporation of MWNTs. Fourier transform infrared spectroscopy showed the existence of hydrogen-bonding interactions between the ether oxygen atoms on FPEOF and proton-donating functionalities on the MWNTs, leading to a strong matrix-filler interfacial adhesion. The low-temperature storage modulus of a FPEOF/MWNT composite (6.0 GPa) is more than twice that of a poly(ethylene oxide)/fluorinated single-walled carbon nanotube composite (2.5 GPa) with the same nanotube loading of 4 wt%. The thermal stability of FPEOF is also improved by the addition of MWNTs. [Copyright &y& Elsevier]