Autothermal reforming of gasoline on Rh-based monolithic catalysts

With an objective to conserve noble metal usage and improve the reforming performance, one engineered catalyst, a Rh-based monolithic catalyst with an optimized composition of 0.3wt%Rh/3wt%MgO/20wt%CeO2-ZrO2 supported on cordierite monolith was developed for autothermal reforming (ATR) of commercial gasoline and its surrogates. At a temperature range of 650-800 degrees C, O-2/C molar ratio of 0.38-0.45 (air as oxygen source) and H2O/C ratio of 2.0, alkanes (e.g., octane) were fully converted into reformate with minor amount of CH4 remaining whereas aromatics (e.g., toluene) converted into CH4-free reformate at a relatively higher temperature. Compared with pellet catalysts, monolithic catalysts with equivalent amount of net catalytic components demonstrated higher activity and selectivity due to the intensified reforming process. This catalyst also showed quite good resilience to sulfur poisoning, although the presence of sulfur in source fuels could make the hydrogen productivity suffer. Moreover, one 1 kW gasoline fuel processor built on a scaled-up catalyst was successfully operated at a (H-2 + CO) throughput of 0.9-1.0 m(3)/h for 60 h. The catalyst sintering and carbon formation which were exacerbated by sulfur-poisoning mainly accounted for the slowly deactivation of the catalyst. The sintering was also aggravated by the low thermal conductivity of the cordierite substrates and by the inharmonic reaction rates of catalytic partial oxidation and steam reforming. Additionally, some issues related to gasoline fuel processor and its monolithic catalysts were also addressed. (C) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved

Overexpression of small heat shock protein LimHSP16.45 in Arabidopsis enhances tolerance to abiotic stresses.

Small heat shock proteins (smHSPs) play important and extensive roles in plant defenses against abiotic stresses. We cloned a gene for a smHSP from the David Lily (Lilium davidii (E. H. Wilson) Raffill var. Willmottiae), which we named LimHSP16.45 based on its protein molecular weight. Its expression was induced by many kinds of abiotic stresses in both the lily and transgenic plants of Arabidopsis. Heterologous expression enhanced cell viability of the latter under high temperatures, high salt, and oxidative stress, and heat shock granules (HSGs) formed under heat or salinity treatment. Assays of enzymes showed that LimHSP16.45 overexpression was related to greater activity by superoxide dismutase and catalase in transgenic lines. Therefore, we conclude that heterologous expression can protect plants against abiotic stresses by preventing irreversible protein aggregation, and by scavenging cellular reactive oxygen species

An Angle-Stable Ultra-Wideband Single-Layer Frequency Selective Surface Absorber

An ultra-wideband polarization-insensitive frequency selective surface (FSS) absorber is proposed for S to K-band applications. The absorber comprises two compensation slabs, a lossy FSS layer and a grounded dielectric plate. The FSS unit cell is a combination of a second-order Chinese knot and a cross. To enhance the bandwidth and angular stability of the single-layer FSS absorber, a compensation layer composed of FR4 and polymethyl methacrylate (PMMA) slabs is incorporated. The proposed FSS absorber demonstrates a remarkable absorption rate of over 90% within the frequency range of 3.1–22.1 GHz, exhibiting a fractional bandwidth of 150.8%. Even when subjected to an oblique incidence of 45°, the absorber maintains an 80% absorption rate in the frequency range of 4.4–19.1 GHz for both TE and TM polarizations. The total thickness of the FSS absorber is 0.0848 λL (the wavelength at the lowest cutoff frequency), and only 1.08 times the Rozanov limit. To validate the design, a prototype of the proposed absorber was fabricated and measured. Good agreements were observed between the simulations and measurements

Sevoflurane attenuates proliferative and migratory activity of lung cancer cells via mediating the microRNA-100-3p/sterol O-Acyltransferase 1 axis

Recently, evidence has shown that microRNA-100-3p (miR-100-3p) has been revealed as a tumor suppressor in diverse human diseases, while its capability in lung cancer warrants further validation. In this work, we aimed to discuss the impact of sevoflurane on biological functions of lung cancer cells by modulating the miR-100-3p/sterol O-acyltransferase 1 (SOAT1) axis. Lung cancer cell lines (A549 and H460) were treated with various concentrations of sevoflurane. Cell viability, proliferation, migration, and invasion were evaluated using MTT, colony formation, wound healing, and transwell assays. Moreover, miR-100-3p and SOAT1 expressions were evaluated by reverse transcription-quantitative polymerase chain reaction in lung cancer cells. The target interaction between miR-100-3p and SOAT1 was predicted by bioinformatics analysis and verified by the dual-luciferase reporter gene assay. The findings of our work demonstrated that sevoflurane impeded the abilities on viability, proliferation, migration, and invasion of A549 and H460 cells. The expression of miR-100-3p was reduced, and SOAT1 expression was elevated in lung cancer cells. miR-100-3p targeted SOAT1. Besides, sevoflurane could lead to expressed improvement of miR-100-3p or limitation of SOAT1. Downregulation of miR-100-3p or upregulation of SOAT1 restored the suppression of sevoflurane on abilities of viability, proliferation, migration, and invasion in A549 and H460 cells. In the rescue experiment, downregulation of SOAT1 reversed the impacts of downregulation of miR-100-3p on sevoflurane on lung cancer cells. Collectively, our study provides evidence that sevoflurane restrained the proliferation and invasion in lung cancer cells by modulating the miR-100-3p/SOAT1 axis. This article provides a new idea for further study of the pathogenesis of lung cancer

Plant grafting relieves asymmetry of jasmonic acid response induced by wounding between scion and rootstock in tomato hypocotyl.

Plant grafting is a sequential wound healing process. However, whether wounding induces a different jasmonic acid (JA) response within half a day (12 h) after grafting or non-grafting remains unclear. Using the tomato hypocotyl grafting method, we show that grafting alleviates the asymmetrical accumulation of JA and jasmonic acid isoleucine conjugate (JA-Ile) in scion and rootstock caused by wounding, and from 2 h after tomato micrografting, grafting obviously restored the level of JA-Ile in the scion and rootstock. Meanwhile, five JA-related genes, SlLOX11, SlAOS, SlCOI1, SlLAPA and SlJA2L, are detected and show significant changes in transcriptional expression patterns within 12 h of grafting, from asymmetrical to symmetrical, when the expression of 30 JA- and defense-related genes were analyzed. The results indicated that grafting alleviates the asymmetrical JA and defense response between scion and rootstock of the tomato hypocotyl within 12 h as induced by wounding. Moreover, we demonstrate that in the very early hours after grafting, JA-related genes may be involved in a molecular mechanism that changes asymmetrical expression as induced by wounding between scion and rootstock, thereby promoting wound healing and grafting success

Effect of Precipitation Temperature on the Performance of CuO/ZnO/CeO2/ZrO2 Catalyst for Methanol Steam Reforming

A series of CuO/ZnO/CeO2/ZrO2 catalyst samples for methanol steam reforming were prepared by a co-precipitation procedure, and the effect of precipitation temperature on the catalytic performance was investigated. All the samples were characterized by N-2 adsorption, X-ray diffraction, temperature-programmed reduction, and N2O titration. It is shown that the precipitation temperature remarkably influenced the catalyst structure and property. When the precipitation temperature was 60 degrees C, the catalyst exhibited the best activity with suppressed CO formation. Compared with commercial catalyst (CB-7), the CeZr as support instead of the Al2O3 can dramatically improve the conversion at low temperature, effectively inhibit the CO generation, reduce the subsequent CO removing process, which was helpful for methanol stream reforming technology using in the proton exchange membrane fuel cell applications

<i>LimHSP16.45</i> expression profiles for David Lily under abiotic stresses.

<p>qRT-PCR analysis of anthers after 4 h at 4°C or 45°C, or after exposure for 7 d to 100 mM NaCl, 1 mM H₂O₂, or 250 mM mannitol. *Indicates significant groups, compared with the control (p<0.05).</p