Recent advances in the heterogeneously catalysed aerobic selective oxidation of alcohols

The heterogeneously catalysed selective aerobic oxidation of alcohols is an important tool for the synthesis of valuable chemical intermediates and a hot topic within both academic and industrial arenas. In this mini-review, selected aspects of catalyst formulation, process operating conditions, and progress in identifying the active sites and surface reaction mechanisms notably through the application of synchrotron radiation, are highlighted. © 2010 Society of Chemical Industry.

Optical biochemical sensors based on long-period fibre gratings UV-inscribed in D-fibre with enhanced sensitivity by HF etching process

We report a new concept of biochemical sensor device based on long-period grating structures UV-inscribed in D-fiber. The surrounding-medium refractive index sensitivity of the devices has been enhanced significantly by a hydrofluoric acid etching process. The devices have been used to measure the sugar concentrations showing clearly an encoding relation between the chemical concentration and the grating spectral response, demonstrating their capability for potential biochemical sensing applications.

Phagocyte oxidation of phospholipids: comparison of hydroperoxide, chlorohydrin and epoxyisoprostane formation by LC-MS

Phagocytic cells produce a variety of oxidants as part of the immune defence, which react readily both with proteins and lipids, and could contribute to the oxidation of low density lipoprotein in atherosclerosis. We have investigated the oxidation of phospholipid vesicles by isolated human polymorphonuclear and mononuclear leukocytes, to provide a model of lipid oxidation in the absence of competing protein. PMA-stimulated cells were incubated with phospholipid vesicles contammg dipalmitoyl phosphatidylcholine (DPPC), palmitoyl-arachidonoyl phosphatidylcholine (PAPC), and stearoyl-oleoyl phosphatidylcholine (SOPC), before extraction of the lipids for analysis by HPLC coupled to electrospray mass spectrometry. In this system, oxidized phosphatidylcholines elute earlier than the native lipids owing to their decreased hydrophobicity, and can be identified according to their molecular mass. The formation of monohydroperoxides of P APC was observed routinely, together with low levels of hydroxides, but no chlorohydrin derivatives of P APC or SOPC were detected. However, the major oxidized product occurred at 828 m/z, and was identified as I-palmitoyl-2-(5,6-epoxyisoprostane E2)-sn-glycero-3-phosphocholine. These results show that phagocytes triggered by PMA cause oxidative damage to lipids predominantly by free radical mechanisms, and that electrophilic addition involving HOCl is not a major mechanism of attack. The contribution of myeloperoxidase and metal ions to the oxidation process is currently being investigated, and preliminary data suggest that myeloperoxidase-derived oxidants are responsible for the epoxyisoprostane phospholipid formation. The identification of an epoxyisoprostane phospholipid as the major product following phagocyte-induced phospholipid oxidation is novel and has implications for phagocyte involvement in atherogenesis.

Enhanced process verification through re-engineering the manufacturing procedure

In today’s modern manufacturing industry there is an increasing need to improve internal processes to meet diverse client needs. Process re-engineering is an important activity that is well understood by industry but its rate of application within small to medium size enterprises (SME) is less developed. Business pressures shift the focus of SMEs toward winning new projects and contracts rather than developing long-term, sustainable manufacturing processes. Variations in manufacturing processes are inevitable, but the amount of non-conformity often exceeds the acceptable levels. This paper is focused on the re-engineering of the manufacturing and verification procedure for discrete parts production with the aim of enhancing process control and product verification. The ideologies of the ‘Push’ and ‘Pull’ approaches to manufacturing are useful in the context of process re-engineering for data improvement. Currently information is pulled from the market and prominent customers, and manufacturing companies always try to make the right product, by following customer procedures that attempt to verify against specifications. This approach can result in significant quality control challenges. The aim of this paper is to highlight the importance of process re-engineering in product verification in SMEs. Leadership, culture, ownership and process management are among the main attributes required for the successful deployment of process re-engineering. This paper presents the findings from a case study showcasing the application of a modified re-engingeering method for the manufacturing and verification process. The findings from the case study indicate there are several advantages to implementing the re-engineering method outlined in this paper.

Manufacturing process challenges when machining superalloys

The implementation of advanced manufacturing systems with high process capability is an essential requirement for the high value manufacturing industries. To ensure high process capability, industry needs to deal with the requirement for tight tolerances and the unavoidable variations in materials, and manufacturing and inspection processes. In the case of machining superalloys, such variations result in the need to change the machine parameters for producing different batches of materials from different suppliers. This is required in order to get the process under control and reduce waste and defects, leading to better competitiveness. This papers discuss the variability in materials and the corresponding process requirements when machining superalloys, and highlights the impact of metrology in achieving manufacturing process improvement.

Advanced ICT based Training Methods

Report published in the Proceedings of the National Conference on "Education in the Information Society", Plovdiv, May, 2013

Detection and quantification of protein oxidation in sarcopenic models:a mass spectrometry study

Oxidised biomolecules in aged tissue could potentially be used as biomarkers for age-related diseases; however, it is still unclear whether they causatively contribute to ageing or are consequences of the ageing process. To assess the potential of using protein oxidation as markers of ageing, mass spectrometry (MS) was employed for the identification and quantification of oxidative modifications in obese (ob/ob) mice. Lean muscle mass and strength is reduced in obesity, representing a sarcopenic model in which the levels of oxidation can be evaluated for different muscular systems including calcium homeostasis, metabolism and contractility. Several oxidised residues were identified by tandem MS (MS/MS) in both muscle homogenate and isolated sarcoplasmic reticulum (SR), an organelle that regulates intracellular calcium levels in muscle. These modifications include oxidation of methionine, cysteine, tyrosine, and tryptophan in several proteins such as sarcoplasmic reticulum calcium ATPase (SERCA), glycogen phosphorylase, and myosin. Once modifications had been identified, multiple reaction monitoring MS (MRM) was used to quantify the percentage modification of oxidised residues within the samples. Preliminary data suggests proteins in ob/ob mice are more oxidised than the controls. For example SERCA, which constitutes 60-70% of the SR, had approximately a 2-fold increase in cysteine trioxidation of Cys561 in the obese model when compared to the control. Other obese muscle proteins have also shown a similar increase in oxidation for various residues. Further analysis with complex protein mixtures will determine the potential diagnostic use of MRM experiments for analysing protein oxidation in small biological samples such as muscle needle biopsies.

Advanced predictive-analysis-based decision support for collaborative logistics networks

Purpose – The purpose of this paper is to examine challenges and potential of big data in heterogeneous business networks and relate these to an implemented logistics solution. Design/methodology/approach – The paper establishes an overview of challenges and opportunities of current significance in the area of big data, specifically in the context of transparency and processes in heterogeneous enterprise networks. Within this context, the paper presents how existing components and purpose-driven research were combined for a solution implemented in a nationwide network for less-than-truckload consignments. Findings – Aside from providing an extended overview of today’s big data situation, the findings have shown that technical means and methods available today can comprise a feasible process transparency solution in a large heterogeneous network where legacy practices, reporting lags and incomplete data exist, yet processes are sensitive to inadequate policy changes. Practical implications – The means introduced in the paper were found to be of utility value in improving process efficiency, transparency and planning in logistics networks. The particular system design choices in the presented solution allow an incremental introduction or evolution of resource handling practices, incorporating existing fragmentary, unstructured or tacit knowledge of experienced personnel into the theoretically founded overall concept. Originality/value – The paper extends previous high-level view on the potential of big data, and presents new applied research and development results in a logistics application.

Advanced methodologies in dynamic traffic assignment modeling of managed lanes

Managed lane strategies are innovative road operation schemes for addressing congestion problems. These strategies operate a lane (lanes) adjacent to a freeway that provides congestion-free trips to eligible users, such as transit or toll-payers. To ensure the successful implementation of managed lanes, the demand on these lanes need to be accurately estimated. Among different approaches for predicting this demand, the four-step demand forecasting process is most common. Managed lane demand is usually estimated at the assignment step. Therefore, the key to reliably estimating the demand is the utilization of effective assignment modeling processes. ^ Managed lanes are particularly effective when the road is functioning at near-capacity. Therefore, capturing variations in demand and network attributes and performance is crucial for their modeling, monitoring and operation. As a result, traditional modeling approaches, such as those used in static traffic assignment of demand forecasting models, fail to correctly predict the managed lane demand and the associated system performance. The present study demonstrates the power of the more advanced modeling approach of dynamic traffic assignment (DTA), as well as the shortcomings of conventional approaches, when used to model managed lanes in congested environments. In addition, the study develops processes to support an effective utilization of DTA to model managed lane operations. ^ Static and dynamic traffic assignments consist of demand, network, and route choice model components that need to be calibrated. These components interact with each other, and an iterative method for calibrating them is needed. In this study, an effective standalone framework that combines static demand estimation and dynamic traffic assignment has been developed to replicate real-world traffic conditions. ^ With advances in traffic surveillance technologies collecting, archiving, and analyzing traffic data is becoming more accessible and affordable. The present study shows how data from multiple sources can be integrated, validated, and best used in different stages of modeling and calibration of managed lanes. Extensive and careful processing of demand, traffic, and toll data, as well as proper definition of performance measures, result in a calibrated and stable model, which closely replicates real-world congestion patterns, and can reasonably respond to perturbations in network and demand properties.^

The role of protein oxidation in ageing & disease

Ageing is a natural phenomenon of the human lifecycle, yet it is still not understood what causes the deterioration of the human body near the end of the lifespan. One popular theory is the Free Radical Theory of Ageing, which proposes that oxidative damage to biomolecules causes ageing of tissues. The ageing population is affected by many chronic diseases. This study focused on sarcopenia (muscle loss in ageing) and obesity as two models for comparison of oxidative damage in muscle proteins in mice. The aim of the study was to develop advanced mass spectrometry methods to detect specific oxidative modifications to mouse muscle proteins, including oxidation, nitration, chlorination, and carbonyl group formation, but western blotting was also used to provide complementary information on the oxidative state of proteins from aged and obese muscle. Mass spectrometry proved to be a powerful tool, enabling identification of the types of modifications present, the sites at which they were present and percentage of the peptide populations that were modified. Targeted and semi-targeted mass spectrometry methods were optimised for the identification and quantitation of the oxidised residues in muscle proteins. The development of the quantitative methods enabled comparisons of mass spectrometry instruments. Both the Time of Flight and QTRAP systems showed advantages of using the different mass analysers to quantify oxidative modifications. Several oxidised residues were characterised and quantified in both the obese and sarcopenic models, and higher levels of oxidation were found compared to their control counterparts. Residues found to be oxidised were oxidation of proline, tyrosine and tryptophan, dioxidation of methionine, allysine and nitration of tyrosine. However quantification was performed on methionine dioxidation and cysteine trioxidation containing residues in SERCA. The combination of measuring residue susceptibility and functional studies could contribute to understanding the overall role of oxidation in ageing and obesity.

Estudo comparativo dos processos eletroquímicos oxidativos avançados (PEOAs) no tratamento de efluentes contendo corantes orgânicos de difícil degradação

Organic dyes have been widely used in various branches of dyeing industries. These compounds are known to be very toxic, mutagenic, cancinogenic only cause aesthetic pollution and irreversible damage to aquatic ecosystems and human health. Are recalcitrant contaminants due to its high stability and resistance to photobleaching and bio. Given this context, the search for technologies that can minimize the effects of such pollutants is required. In recent decades the Electrochemical Oxidation Process Advanced (PEOAs) based on the generation of strongly oxidizing species (radicals ●OH) offer promising approaches for the prevention of problems caused by industrial effluents. This study analyzed the degradation and mineralization of textile dyes and the study of a real effluent in order to assess the feasibility of PEOAs: Electro-Fenton (EF), Photo Electro-Fenton (PEF) and anodic oxidation (AO), and these methods still was studied the Solar Fotoelectro-Fenton (SPEF) in a pre-pilot plant, in order to study the electrochemical treatment on an industrial scale. In the study has compared the effect of PEOAs in the removal of color, TOC and decay kinetics of degradation of the compounds, and also for using the Congo Red (CR) SPEF studies were performed mineralization current efficiency (MCE). The best results are given to the treatment of the PEF for all the studied dyes. From the results it was possible to choose the PEF as the most effective and promising for application of treatment when compared to other methods of treatment, and prove from SPEF that the process can be used in industrial scales, since this method PEF has been improved and solar irradiation replaced the UVA lamp.

Estudo comparativo dos processos eletroquímicos oxidativos avançados (PEOAs) no tratamento de efluentes contendo corantes orgânicos de difícil degradação

Organic dyes have been widely used in various branches of dyeing industries. These compounds are known to be very toxic, mutagenic, cancinogenic only cause aesthetic pollution and irreversible damage to aquatic ecosystems and human health. Are recalcitrant contaminants due to its high stability and resistance to photobleaching and bio. Given this context, the search for technologies that can minimize the effects of such pollutants is required. In recent decades the Electrochemical Oxidation Process Advanced (PEOAs) based on the generation of strongly oxidizing species (radicals ●OH) offer promising approaches for the prevention of problems caused by industrial effluents. This study analyzed the degradation and mineralization of textile dyes and the study of a real effluent in order to assess the feasibility of PEOAs: Electro-Fenton (EF), Photo Electro-Fenton (PEF) and anodic oxidation (AO), and these methods still was studied the Solar Fotoelectro-Fenton (SPEF) in a pre-pilot plant, in order to study the electrochemical treatment on an industrial scale. In the study has compared the effect of PEOAs in the removal of color, TOC and decay kinetics of degradation of the compounds, and also for using the Congo Red (CR) SPEF studies were performed mineralization current efficiency (MCE). The best results are given to the treatment of the PEF for all the studied dyes. From the results it was possible to choose the PEF as the most effective and promising for application of treatment when compared to other methods of treatment, and prove from SPEF that the process can be used in industrial scales, since this method PEF has been improved and solar irradiation replaced the UVA lamp.

Modelagem da degradação de fenol em efluentes aquosos através do processo de foto-fenton

Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO•) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R² = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R² = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.

Modelagem da degradação de fenol em efluentes aquosos através do processo de foto-fenton

Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO•) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R² = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R² = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.

Degradação de paracetamol empregando tecnologia oxidativa avançada baseada em fotocatálise heterogênea usando irradiação artificial e solar

In this work, the oxidation and mineralization of paracetamol, based in an advanced oxidative process promoted by heterogeneous photocatalysis, was evaluated. The action of two photocatalysts (titanium dioxide, and a composite based on the association between titanium dioxide and zinc phthalocyanine dye) was studied. First of all, experiments in laboratory scale were performed using as radiation font a 400 W high pressure mercury lamp. The mineralization of paracetamol, promoted by both photocatalysts, was evaluated working with 4L of solution containing 10 mg L-1 of paracetamol and 100 mg L-1 of photocatalyst. To find the best experimental conditions, the influence of hydrogen peroxide concentration and pH was evaluated for the reactions. The best results for the reactions in laboratory scale was obtained using 33,00 mg L-1 of hydrogen peroxide in natural pH (6,80). Under these conditions, 100% oxidation was reached in just 40 minutes of reaction using TiO2 P25, while the mineralization was 78%. Using the composite, the mineralization was 63% in 2 hours of reaction and a oxidation of almost 100% was reached after 60 minutes. A CPC reactor (compound parabolic concentrator) was employed in the expanded work scale, using the sun as irradiation source. In this case the experiments were performed using 50 L of aqueous solution containing 10 mg L-1 of paracetamol and 100 mg L-1 of photocatalyst. The assays were done at pH 3,00 and natural pH (6,80). The used concentration of hydrogen peroxide was 33,00 mg L-1, adopted after laboratory scale studies. The reaction at pH 3,00 shows to be more advantageous, since under natural pH (6,80), the use of deionized water was necessary to prepare the solutions, probably because the deleterious action of carbonate ions, known hydroxyl radical scavengers. Using solar irradiation, the reaction mediated by the composite was more efficient when compared with the assays under laboratory scale since the composite presents the advantage of promoting a better use of visible radiation. Under these conditions, the mineralization increased from 40% to 56% under pH 3,00. At natural pH the oxidation occurred more slowly and the mineralization decreased from 56% to 50%. Thus, the use of pH 3,00 will be more interesting in real scale applications, even if it is necessary the pH correction before the discard of the treated effluent to the environment.