Study on reuse of metal oxide-promoted sulphated zirconia in acylation reactions

A series of sulphated zirconia samples (SZ) promoted with Al₂O₃, Ga₂O₃, and Fe₂O₃ were synthesized by co-precipitation at constant pH and aged under reflux conditions. Structural, surface and catalytic properties of the samples were investigated using N₂ adsorption/desorption, thermal analysis, in-situ FTIR spectroscopy, TPR–MS and EGA–MS measurements. The catalytic performance of promoted SZ in anisole acylation has been investigated. Promotion by either Fe₂O₃ or Ga₂O₃ was found to increase the catalytic activity (yield) after recycle of catalysts with respect un-promoted sample, whereas promotion by Al₂O₃ was observed to increase the conversion but not the yield. It is worth noting that all systems present high selectivity to the p-metoxyacetophenone product.     

Crested barrier in the tunnel stack of non-volatile memories

In this work a high-k insulating film is deposited on the SiO₂ tunnel oxide of MOS capacitors designed for non-volatile memory applications. The advantages of this approach derive from the asymmetric band diagram, which lowers the Fowler–Nordheim tunnel erase barrier, without affecting the program operation. This results in lower erase voltage and much shorter erase times. In fact, in the proposed structure the erase voltage is about 20% lower and the erase current three thousands times greater than in conventional MOS with pure-SiO₂ tunnel oxide and the same equivalent oxide thickness (15 nm). At the same time, the larger physical thickness prevents from charge loss, and guarantees data retention. The goal of such device is to improve the memory performances without degrading reliability.     

Characterisation of Italian commercial apricot juices by high-performance liquid chromatography analysis and multivariate analysis

The modern fruit juice industry needs their products to be characterized by high-quality attributes to meet consumers’ expectation. In this view, the composition of 26 Italian commercial apricot juices obtained from organic, integrated and conventional agriculture was analysed for carbohydrates, organic acids, amino acids, phenolic compounds and furanic compounds by high-performance liquid chromatography (HPLC). The content of 5-hydroxymethylfurfural in apricot juices (range 0.1–18 mg/l) was within the regulatory limit of 20 mg/l. The lack of furanic compounds in apricot fresh fruits confirmed their importance as quality markers of heating condition during processing and storage of fruit juices. Univariate analysis disclosed some significant differences among the composition of the apricot juices in terms of glucose, fructose, malic acid, glycine, chlorogenic acid, rutin, and a^∗-parameter (redness). Principal component analysis on chemical composition of apricot juices resulted in two principal components (PCs) that accounted for 66% of the total variance. Organic apricot juices showed some separation from the other juices, whereas a lack of distinction between integrated and conventional juices appeared.     

Brazilian red propolis: unreported substances, antioxidant and antimicrobial activities

BACKGROUND: Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography–mass spectrometry and high‐performance liquid chromatography–diode array detection–electrospray ionization‐mass spectrometry. Antimicrobial and antioxidant activities were also obtained. RESULTS: The propolis sample contained low content of narigenin‐8‐C‐hexoside, this being the first report of a C‐glycoside in propolis. The main constituent found was characterized as 3,4,2′,3′‐tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)‐vestitol, (3S)‐7‐O‐methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans‐anethol, methyl eugenol, elimicin, methoxyeugenol and cis‐asarone, and the triterpenic alcohols lupeol and α‐ and β‐ amyrins. The methanol extract exhibited high antioxidant activities by 2,2‐diphenyl‐1‐picrylhydrazyl and β‐carotene/linoleic acid assay methods, and antimicrobial activity toward Gram‐positive and Gram‐negative bacteria. CONCLUSION: Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2′,3′‐tetrahydroxychalcone and a flavone C‐glycoside in a propolis sample. Copyright © 2011 Society of Chemical Industry     

Soft-Seeded Pomegranate (<Emphasis Type="Italic">Punica granatum</Emphasis> L.) Varieties: Preliminary Characterization and Quality Changes of Minimally Processed Arils During Storage

A preliminary characterization of two new soft-seeded pomegranate varieties (MR-100® and KINGDOM®) based on their main physico-chemical and nutritional parameters was reported. The two varieties showed significant differences (p ≤ 0.05) in polyphenols, anthocyanins and antioxidant activity. Kingdom pomegranate had higher polyphenols (2524.73 mg GAE/L), anthocyanins (752.49 mg C₃gE/L) and antioxidant activity (EC₅₀ 13.58 μL/mL) than MR-100 (1792.74 mg GAE/L, 141.29 mg C₃gE/L and EC₅₀ 47.53 μL/mL, respectively). Moreover, minimally processed arils of the two varieties were packaged in semipermeable and micro-perforated film at 5 °C, and the quality changes that occurred during storage condition (15 days) were investigated. During storage, Kingdom arils exhibited a better performance in terms of antioxidant activity, polyphenols and anthocyanin content with respect to MR-100. Furthermore, the packaging systems did not affect the estimated quality parameters for both varieties. Based on the sensory evaluation and microbial counts, both aril varieties reached, at 15-day storage, suitable values for commercial purpose.     

Simulating the impact of biofuel development on country-wide land-use change in India

India’s growing population and economy generate an increasing demand for energy. Facing the decline of global fossil fuel resources, the Indian government and energy industry are considering the long-term expansion of biofuel production in order to increase energy security. This development leads to a strong competition of energy crops versus food crops for land and may result in an increasing pressure on natural resources. In a pilot scenario study, the LandSHIFT model is applied to assess the impact of biofuel production on land-use change in India up to the year 2030. The model aims at the spatially explicit simulation of land-use change and its relation to other global change processes on the national up to the global scale. It explicitly addresses competition between land-use activities such as human settlement, biofuel production and food production as well as the resulting effects on the spatial extent of natural land. Baseline of the study is a simulation with drivers from the “Order from Strength” scenario of the Millennium Ecosystem Assessment. To illustrate the consequences of expanded biofuel production for the extent of natural land, we calculate three scenarios of bioethanol production to substitute 5%, 10% and 20% of the expected petrol demand in 2030. In the simulations shown, a comprehensive linkage is made between driving forces (such as population change) and policies (such as biofuel usage) that will affect land-use change over the coming decades.     

Initial Beam Test Results from a Silicon-Strip Detector with VLSI Readout

Silicon detectors with 256 strips, having a pitch of 25 ?m, and connected to two 128 channel NMOS VLSI chips each (Microplex), have been tested in relativistic charged particle beams at CERN and at the Stanford Linear Accelerator Center. The readout chips have an input channel pitch of 47.5 ?m and a single multiplexed output which provides voltages proportional to the integrated charge from each strip. The most probable signal height from minimum ionizing tracks was 15 times the rms noise in any single channel. Two-track traversals with a separation of 100 ?m were cleanly resolved.     

ADA: A language for robot programming?

Robot programming languages are emerging from their experimental stage and entering an assessment phase. Their main features are illustrated and a parallel with ADA is proposed. The comparison is positive for ADA, in the sense that ADA provides most of the required capabilities. The ability of reasoning on object models and taking decisions will play an increasing role in the future. In this case the role of ADA would possibly change and its interest as robot programming language decrease.     

Phenolic compounds in olive oil and olive pomace from Cilento (Campania,Italy) and their antioxidant activity

Virgin olive oil (VOO) has nutritional and sensory characteristics that make it unique and a basic component of the Mediterranean diet. Its importance is mainly attributed to its richness in polyphenols, which act as natural antioxidants and may contribute to the prevention of several human diseases. In this paper we report the determination and quantification of oleocanthal, one of the main substances responsible for the bitter taste of olive oil, together with a quali-quantitative analysis by HPLC analytical methods of phenolics from Cilento VOO and olive oil pomace. The total phenolic content was also determined and the in vitro antioxidant and free-radical scavenging activities by DPPH test was evaluated. A superoxide anion enzymatic assay was also carried out and the results were confirmed by the inhibition of xanthine oxidase activity assay. The possible protective role played by VOO secoiridoids on injurious effects of reactive oxygen metabolites on the intestinal epithelium, using Caco-2 human cell line, was investigated.