On the modification of photocatalysts for improving visible light and UV degradation of gas-phase toluene over TiO2

The photocatalytic behavior of different TiO₂-based photocatalysts was reported for gas-phase toluene removal under both UV and visible light illumination, and compared to that of commercial P25 (Degussa) TiO₂. Promotion by sulfates and the use of nanosized anatase TiO₂ were reported to strongly increase the toluene removal efficiency under UV illumination. Nanosized-anatase was prepared by a protecting group sol–gel synthesis using hexamethyldisilazane as crystallite growth inhibitor. Sulfates played a double positive role, with photogenerated electrons transfer effects limiting charge recombination and as repulsive species for strongly adsorbed aromatic intermediates that act as poisons. The decrease in particle size obtained on nanosized anatase TiO₂ (5 nm) yielded a considerable enhancement in the toluene removal efficiency. Pure high surface area rutile has been synthesized at low temperature by a polyethylenglycol-containing sol–gel method for visible light activation purposes. A two-way semiconductor coupling phenomenon, consisting of a reciprocal electron/hole transfer between two visible light-activated oxides, rutile TiO₂ and WO₃, was proposed to explain the large gain in efficiency when adding low amounts of WO₃ to rutile TiO₂.     

Hardware Implementation of Enhancement Embedded Reduced Runtime Recovery Algorithm for Compressively Sensed Images

Compressed sensing is based on the principle that, through optimization, the sparsity of a signal can be exploited to recover it from fewer samples than required by the criterion. In compressed sensing, data is compressed and converted into fewer measurements and transmitted through wireless channel which is reconstructed at the receiver. Since very few samples are used for reconstruction, there are possibilities of degradation in quality of reconstruction. Unlike traditional methods, enhancement can now be done using the recent technique of compressed sensing by embedding image enhancement techniques like edge detection, histogram, filtering and their combinations with CS recovery procedure. This work proposes such a method by binding the image enhancement techniques along with the compressed sensing process. Filter of Gaussian filter (FGF), a combinational filter proposed in this study enables an increase in PSNR of 1 dB when compared to other filtering techniques besides using least number of measurements and maintaining minimum time consumption. The runtime difference with and without the FGF is ~?3 s, which is affordable even in hardware with minimum specifications. Real time experimentation of embedded enhancement CS was carried out in WINGZ board to prove the feasibility of enhanced recovery process with lower end hardware.     

Key relationship-based determinants of project performance in China

The aim of this paper is to investigate the relationship-based factors that affect performance of general building projects in China. Thirteen performance metrics that may be used to measure the success level of construction projects are defined and categorized into four groups namely cost, schedule, quality and relationship performance. Fourteen risks inherent in relationships and 16 tools expected to facilitate relationship building that may affect project success are identified. Data of different projects were collected in China via a self-administered postal survey. Multiple linear regression models are developed to help explain the variance in different performance metrics. It has been found that ten risks and nine tools have either positive or negative influence on project performance to some different extents and in different project development process stages. Detailed explanations are made, especially to those variables bearing unexpected signs. It is recommended that firms in the Chinese construction industry manage the relationship-based factors that are significant in the MLR models so as to achieve project success.     

Toxicity of lipid-soluble copper(II) complexes to the marine diatom Nitzschia closterium: Amelioration by humic substances

Algal assays, using the marine diatom Nitzschia closterium, have established that humic acid (5 mg kg⁻¹) can ameliorate the toxicity of the lipophilic complex Cu(oxine)₂ (3 × 10⁻⁸ mol l⁻¹ in unsupplemented seawater). The toxicity of Cu(PAN)₂ is not ameliorated [PAN = 1-(2-pyridylazo)-2-napthol]. In conjunction with previous visible absorption spectrophotometry and polarographic measurements it was established that humic acid sequesters copper(II) from the hydrophobic complexes, releasing a ligand molecule. The copper(II) toxicity may be ameliorated provided the ligand itself is not toxic.Fulvic acid was significantly less effective in ameliorating toxicity. Because of the significant competition from Ca(II) and Mg(II) in seawater, it is inferred that humic substances may be more effective in ameliorating toxicity of hydrophobic copper complexes in fresh water.     

Magnetic Imaging of Cyanide‐Bridged Co‐ordination Nanoparticles Grafted on FIB‐Patterned Si Substrates

Prussian blue CsNiCr nanoparticles are used to decorate selected portions of a Si substrate. For successful grafting to take place, the Si surface needs first to be chemically functionalized. Low‐dose focused ion beam patterning on uniformly functionalized surfaces selects those portions that will not participate in the grafting process. Step‐by‐step control is assured by atomic force and high‐resolution scanning electron microscopy, revealing a submonolayer distribution of the grafted nanoparticles. By novel scanning Hall‐probe microscopy, an in‐depth investigation of the magnetic response of the nanoparticles to varying temperature and applied magnetic field is provided. The magnetic images acquired suggest that low‐temperature canted ferromagnetism is found in the grafted nanoparticles, similar to what is observed in the equivalent bulk material.     

Biochemical interpretation of quantitative structure-activity relationships (QSAR) for biodegradation of N-heterocycles: a complementary approach to predict biodegradability

Prediction of the biodegradability of organic compounds is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. We combined quantitative structure-activity relationships (QSAR) with the systematic collection of biochemical knowledge to establish rules for the prediction of aerobic biodegradation of N-heterocycles. Validated biodegradation data of 194 N-heterocyclic compounds were analyzed using the MULTICASE-method which delivered two QSAR models based on 17 activating (OSAR 1) and on 16 inactivating molecular fragments (GSAR 2), which were statistically significantly linked to efficient or poor biodegradability, respectively. The percentages of correct classifications were over 99% for both models, and cross-validation resulted in 67.9% (GSAR 1) and 70.4% (OSAR 2) correct predictions. Biochemical interpretation of the activating and inactivating characteristics of the molecular fragments delivered plausible mechanistic interpretations and enabled us to establish the following biodegradation rules: (1) Target sites for amidohydrolases and for cytochrome P450 monooxygenases enhance biodegradation of nonaromatic N-heterocycles. (2) Target sites for molybdenum hydroxylases enhance biodegradation of aromatic N-heterocycles. (3) Target sites for hydratation by an urocanase-like mechanism enhance biodegradation of imidazoles. Our complementary approach represents a feasible strategy for generating concrete rules for the prediction of biodegradability of organic compounds.     

Targeting a polyketide synthase gene for Aspergillus carbonarius quantification and ochratoxin A assessment in grapes using real-time PCR

Aspergillus carbonarius is an ochratoxin producing fungus that has been considered to be responsible of the ochratoxin A (OTA) contamination in grapes and wine. In order to monitor and quantify A. carbonarius, a specific primer pair Ac12RL_OTAF/Ac12RL_OTAR has been designed from the acyltransferase (AT) domain of the polyketide synthase sequence Ac12RL3 to amplify 141 bp PCR product. Among the mycotoxigenic fungi tested, only A. carbonarius gave a positive result. This specific primer pair was also successfully employed in real-time PCR conjugated with SYBR Green I dye for the direct quantification of this fungus in grape samples. A positive correlation (R(2)=0.81) was found between A. carbonarius DNA content and OTA concentration in 72 grape samples, allowing for the estimation of the potential risk from OTA contamination. Consequently, this work offers a quick alternative to conventional methods of OTA quantification and mycological detection and quantification of A. carbonarius in grapes.     

Social presence effects in the Stroop task: Further evidence for an attentional view of social facilitation.

In contrast with R. B. Zajonc's (1965) classic view about social facilitation–inhibition (SFI) effects, it was found that the presence of relatively unpredictable audiences and forced social comparison with a slightly superior coactor both facilitated performance in the Stroop task while inhibiting automatic verbal processing. Not only do these findings reveal that social presence can help inhibit the emission of dominant responses, providing further support for an attentional view of SFI effects, but they also demonstrate the power of social situations over what has been thought to be invariant automatic processing. As such, they are inconsistent with the view reiterated in more than 500 articles on Stroop interference over the past 60 years and suggest that more attention should be paid to the situations in which cognition takes place. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aquatic Toxicity Effects and Risk Assessment of ‘Form Specific’ Product-Released Engineered Nanomaterials

The study investigated the toxicity effects of ‘form specific’ engineered nanomaterials (ENMs) and ions released from nano-enabled products (NEPs), namely sunscreens, sanitisers, body creams and socks on Pseudokirchneriella subcapitata, Spirodela polyrhiza, and Daphnia magna. Additionally, risk estimation emanating from the exposures was undertaken. The ENMs and the ions released from the products both contributed to the effects to varying extents, with neither being a uniform principal toxicity agent across the exposures; however, the effects were either synergistic or antagonistic. D. magna and S. polyrhiza were the most sensitive and least sensitive test organisms, respectively. The most toxic effects were from ENMs and ions released from sanitisers and sunscreens, whereas body creams and sock counterparts caused negligible effects. The internalisation of the ENMs from the sunscreens could not be established; only adsorption on the biota was evident. It was established that ENMs and ions released from products pose no imminent risk to ecosystems; instead, small to significant adverse effects are expected in the worst-case exposure scenario. The study demonstrates that while ENMs from products may not be considered to pose an imminent risk, increasing nanotechnology commercialization may increase their environmental exposure and risk potential; therefore, priority exposure cases need to be examined.